Jean-François Marchand

H → γγ dans le détecteur ATLAS au LHC

Les mesures de précision et les prédictions théoriques indiquent qu'un boson de Higgs léger, avec une masse comprise entre 114 et 150 GeV, est favorisé. Dans cette région de masse, l'un des canaux de recherche les plus importants est la désintegration en 2 photons. On va s'intéresser a la possibilité de découverte de ce boson dans le canal diphotons avec le détecteur ATLAS au LHC. Après avoir vu l'impact des performances du détecteur, on s'intéressera à l'analyse inclusive et à la recherche de 2 photons avec association de jets, puis nous évaluerons le potentiel de découverte. Cette étude est basée sur une simulation MC réaliste du détecteur.

Introduction

Le canal de désintegration du boson de Higgs H → γγ est l'un des canaux de découverte les plus prometteurs pour un boson de Higgs léger dans le cadre du Modèle Standard. Malgré un rapport de branchement faible (2.2 • 10 -3 pour m H = 120GeV), ce canal a l'avantage d'avoir une signature simple et une très bonne résolution en masse (d'environ 1.5GeV). Pour permettre l'obtention de résultats optimaux, il est nécessaire d'avoir une bonne reconstruction-identification des photons, de bien manipuler les conversions de photons et de bien mesurer la direction des photons. Dans l'étude présentée ici, des corrections QCD d'ordre supérieur sont considérées pour le signal et le bruit de fond et l'on prend également en compte la contribution de la fragmentation des partons durs en photons. On décrira à la fois l'analyse inclusive et la production de deux photons en association avec des jets. On comparera les résultats obtenus pour la signification statistique en utilisant un fit multivariable du maximum de likelihood à ceux du comptage simple d'évènements. Tous les résultats présentés ici sont basés sur une simulation Monte Carlo réaliste d'évènements de signal et de bruit de fond.

Signal et bruit de fond

Le boson de Higgs est principalement produit par fusion de gluons par l'intermédiaire d'une boucle de quarks top et par le processus de fusion de bosons vecteurs (VBF). L'avantage du processus VBF êtant l'existence de jets vers l'avant. La production en association avec des W , Z ou paires de t t peut aussi être La désintegration du boson de Higgs est réalisée par l'intermédiaire de boucles de bosons W ou de quarks top. Le bruit de fond peut quant à lui être séparé en deux catégories : Le bruit de fond irréductible, qui vient de la production de deux photons isolés (processus de Born, de fragmentation ou de box), et le bruit de fond réductible, qui provient d'évènements avec au moins un faux photon (comme par exemple un jet mal identifié comme photon). Les diagrammes de Feynman de ces processus sont présentés sur la figure 1.2 pour le signal et 1.3 pour le bruit de fond.

H 0 t γ γ H 0 γ W γ H 0 W W γ γ

Reconstruction et identification des photons

Les photons sont reconstruits sur la base de clusters électromagnétiques de tailles différentes pour les photons convertis et non-convertis. La position des clusters est corrigée pour tenir compte des biais systématiques connus. L'énergie est reconstruite en utilisant des poids longitudinaux pour corriger les effets de perte d'énergie devant le calorimètre électromagnétique, les fuites longitudinales et les pertes d'énergie en dehors du cluster. Des poids différents sont appliqués pour les photons convertis et les photons non-convertis.

Une méthode d'identification des photons est nécessaire pour réduire le bruit de fond des jets en dessous du bruit de fond irréductible. Pour cela on utilise une méthode basée sur des coupures sur la forme des gerbes électromagnétiques : Le second compartiment du calorimètre électromagnétique et le calorimètre hadronique permettent la réjection des jets du fait de leurs larges gerbes, la segmentation fine du premier compartiment du calorimètre électromagnétique permet la séparation entre γ et π 0 .

Pour augmenter la qualité des photons reconstruits, on utilise également une isolation de ceux-ci par les traces reconstruites.

Reconstruction des conversions

La reconstruction des conversions est importante pour l'analyse H → γγ. En effet, des études Monte Carlo montrent que 57% des évènements H → γγ ont au moins un photon converti avec un rayon de conversion inférieur à 80cm (ce qui correspond au dernier point où l'on peut espérer reconstruire une trace) et 35% des évènements H → γγ ont au moins un photon converti avec un rayon de conversion inférieur à 35cm (ce qui correspond aux conversions reconstructibles avec la version du software utilisée dans cette étude).

Deux types de conversions sont reconstruites : Les conversions à deux traces, reconstruites par un algorithme de vertexing dédié utilisant deux traces de charges opposées en entrée, et les conversions à une traces, reconstruites lorsque l'une des deux traces n'a pas été reconstruite par le détecteur ou lorsque l'algorithme de vertexing échoue. On sépare alors un électron de conversion d'un électron primaire par le signal laissé dans la première couche de pixels.

Une efficacité globale de reconstruction des conversions de 66.4% est obtenue pour des conversions de rayon inférieur à 35cm. On peut également noter que l'ajout des photons convertis dans l'analyse H → γγ permet de gagner environ 21% d'évènements H → γγ (14% de conversions à deux traces et 7% de conversions à une trace).

Masse invariante et résolution

La masse invariante de la paire de deux photons est calculée à partir d'un fit Gaussien assymétrique (dans l'intervalle [-2σ, +3σ], comme illustré sur la figure 1.6. La résolution relative en masse σ m /m est proche de 1.2% et seulement dégradée de quelques pourcents lorsque l'on ajoute le bruit d'empilement (pileup) de 10 33 cm -2 s -1 . Pour un boson de Higgs simulé avec une masse de 120GeV, la masse reconstruite est de 119.46GeV avec une résolution de 1.46GeV (et respectivement 119.47GeV et 1.52GeV avec pileup). On peut observer un décalage en masse vers les faibles masse qui est dû aux photons convertis.

[GeV] dans une fenêtre de masse de ±2 GeV autour de 120 GeV

Fit du maximum de Likelihood

Un fit multivariable du maximum de likelihood a été développé pour l'analyse H → γγ. Il utilise les informations discriminantes des propriétés cinématiques et topologiques des évènements H → γγ : Les variables utilisées sont la masse invariante de la paire de photons, l'impulsion transverse du boson de Higgs, et | cos θ * | où θ * est l'angle de désintegration du boson de Higgs.

On catégorise les évènements pour séparer les données en plusieurs sous-parties : On sépare des souspopulations d'évènements avec des propriétés différerntes, les différentes catégories peuvent alors avoir des valeurs de PDF différentes. Cette catégorisation donne une description fine des données, réduit les biais liés à la corrélation entre variables et augmente finalement la précision du modèle de Likelihood.

Les catégories utilisées pour le fit sont les suivantes : On utilise trois catégories en pseudo-rapidité, deux catégories selon que les photons sont convertis ou nonconvertis (fig. 1.10) et trois catégories de production du boson de Higgs : H + 0, 1, 2 jets.

Conclusion

L'analyse combinée de H+0jet, H+1jet et H+2jets augmente la signification statistique d'environ 25% par rapport à l'analyse inclusive. L'utilisation d'un fit de maximum de likelihood a été étudiée pour augmenter la sensibilité : les résultats montrent que cette signification statistique augmente d'environ 40% par rapport à l'analyse inclusive. Une découverte à 5σ devrait alors être possible avec une luminosité integrée de 20-30fb -1 .

Beaucoup d'améliorations ont été faites depuis les études précédentes mais beaucoup sont toujours en cours, comme la gestion des conversions, le pointing, l'isolation, la calibration des photons... Sans oublier que du travail sera nécessaire pour comprendre les performances du détecteur avec les premières données.

Fig. 1 . 1 -

 11 Fig. 1.1 -Rapport d'embranchement en fonction de la masse du boson de Higgs pour différents canaux de désintegration

Fig. 1 .Fig. 1 .

 11 Fig. 1.2 -Diagrammes de Feynman pour le signal

Fig. 1 .

 1 Fig. 1.4 -Représentation schématique du détecteur interne, utilisé pour la reconstruction des conversions

Fig. 1 .

 1 Fig. 1.5 -Schéma du fit utilisé pour mesurer la direction des photons

Fig. 1

 1 Fig. 1.6 -Distribution de la masse invariante des deux photons, pour un boson de Higgs de m H = 120GeV

Fig. 1 .

 1 Fig. 1.7 -Distribution de la masse invariante des deux photons en terme de section efficace en fb pour l'analyse inclusive

Fig. 1 .

 1 Fig. 1.8 -Distribution de la masse invariante des deux photons en terme de section efficace en fb pour l'analyse H + 1 jets

Fig. 1 .Tab. 1 . 1 -

 111 Fig. 1.9 -Distribution de la masse invariante des deux photons en terme de section efficace en fb pour l'analyse H + 2 jets

Fig. 1 .

 1 Fig. 1.10 -Répartition des catégories en pseudorapidité dans le cas des photons convertis

  Le tableau 1.3 présente quant à lui les résultats obtenus par le fit multivariable en laissant libre la masse du boson de Higgs ou en la fixant à une valeur donnée.Tab. 1.3 -Significations statistiques obtenues par fit du maximum de likelihood pour différentes masse de boson de Higgs et en fixant ou non la masse

	m H	Inclusive	H	H	Combiné
	(GeV)		+ 1 jet + 2 jets
	120	2.6	1.8	1.9	3.3
	130	2.8	2.0	2.1	3.5
	140	2.5	1.8	1.7	3.0
	Tab. 1.2 -Significations statistiques obtenues par
	comptage d'évènements, pour différentes masse de bo-
	son de Higgs et pour les différents types d'analyse con-
	sidérés
	Le fit avec masse fixée permet d'augmenter la significa-
	tion statistique d'environ 40% par rapport à l'analyse
	inclusive.
	m H (GeV) Masse libre Masse fixée
		120	2.8	3.6
		130	3.4	4.2
		140	3.2	4.0
	1.9 Potentiel de découverte
	On va ici comparer la signification statistique atten-
	due obtenue par comptage d'évènements et par l'utili-
	sation du fit précédemment décrit, pour 10fb -1 de lu-
	minosité intégrée et dans une fenêtre de masse de ±1.4σ
	autour de la masse du boson de Higgs.
	Le tableau 1.2 présente les résultats obtenus par
	comptage d'évènements et montre que la combinaison
	des différentes analyses permet d'augmenter la signifi-
	cation statistique d'environ 25% par rapport à l'analyse
	inclusive seule.

Remerciements

C'est un plaisir de remercier les coordinateurs des différentes sessions sans oublier les gentils organisateurs !


Vincent Zoma

Wendpanga Jacques

Ismaël Tarama

Alassane Traore

Sia Coulibaly

Potentialities and local conservation strategy of Ceiba pentandra (L.) Gaertn in the Banwa province in Burkina Faso

Keywords: Ceiba pentandra, regeneration, management strategies, Burkina Faso

Faced with the risk of disappearance of certain plant species linked to the combined actions of man and the climate, it is recognized that the preservation of tropical biodiversity constitutes a major challenge. According to the International Union for Conservation of Nature, currently some species from tropical Africa such as the species Ceiba pentandra (L.) Gaertn could be threatened with extinction. In this context, the present research carried out in the West of Burkina Faso aims to analyze the modalities of a sustainable management of Ceiba pentandra (L.) Gaertn through an improvement of knowledge on the species. The work of collecting both qualitative and quantitative data highlights, on the one hand, the spatial analysis of the population and the dendrometric characteristics of the species. This research on the other hand, highlights the state of regeneration of ceiba pentandra (l.) gaertn and local management strategies which don't guarantee the sustainability of this resource.

Introduction

"We live among plants; look around yourself or around the cities: the landscape is made of plants, they populate our dishes, make and retain our soils, adorn our lives and our walks... But in this cohabitation, we are often difficult neighbours" (French Agency for Biodiversity, 2019, p.3). In fact, according to the latest update of the Red List of Threatened Species of the International Union for Conservation of Nature (IUCN), 17,291 out of 47,677 listed species are threatened with extinction (IUCN, 2009) [START_REF]The extinction crisis is still gaining ground -IUCN[END_REF] . The African continent is home to a wealth of natural species, ranging from individual species to endemic habitats (IUCN, 1994) [START_REF]Guidelines for Protected Area Management Categories[END_REF] . However, the Research Institute for Development (IRD, 2019) emphasizes that in front of the anthropic and climatic threats on nature, the preservation of tropical biodiversity constitutes a major challenge; as 31.7% of vascular plant species in tropical Africa could be threatened with extinction. In this context, there is growing interest in the protection of natural species in general and certain particular plant species such as Ceiba pentandra (L.) Gaertn, which is found almost everywhere in West Africa (IUCN, 1994, op.cit) [START_REF]Guidelines for Protected Area Management Categories[END_REF] . Ceiba pentandra (L.) Gaertn also called Kapok is a majestic-looking tree (S. Guinko, 2009) [START_REF] Guinko | Illustrated flora of the Kou Classified Forest[END_REF] . It has a pantropical geographical distribution, in Burkina Faso, Senegal, Cameroon, Central America, Antilles, India, etc. (M. Eyog, and, al.,2006) [START_REF] Eyog | The Edible Forest Fruit Trees of Cameroon[END_REF] . It is a fast-growing pioneer species that can grow in all areas, including those with poor soil fertility (C. Abengmeneng, and al., 2016) [START_REF] Abengmeneng | Genetic Relationship Among 36 Genotypes of Ceiba pentandra (L.) as Revealed by RAPD and ISSR Markers[END_REF] . The species is of great importance to humans. It is used for food, timber and service, pharmacopoeia, crafts, and is often planted in alignment in towns and villages (M. Eyog, and al.,2006, op.cit; M. Rivers & J. Mark, 2017) [START_REF] Eyog | The Edible Forest Fruit Trees of Cameroon[END_REF][START_REF] Rivers | Ceiba pentandra. The IUCN Red List of Threatened Species[END_REF] . However, according to M. Rivers & J. Mark (2017, op.cit) [START_REF] Rivers | Ceiba pentandra. The IUCN Red List of Threatened Species[END_REF] , Ceiba pentandra (L.) Gaertn was assessed for the IUCN red list of threatened species in 2017, though listed as minor concern. Measures must be considered to ensure the conservation of the species. But beforehand it is necessary to know the existing potential. Indeed, as argued by M. Kouyate (2005) [START_REF] Kouyate | Ethnobotanical aspects and study of the morphological, biochemical and phenological variability of Detarium Microcarpum Guill[END_REF] , knowing the traits of the species can indicate whether the disturbance uniformly affects the species of the community or only a certain functional type. In the case of the conservation of threatened and low-numbered species, the priority is to describe the characteristics of these species as exhaustively as possible. This information can more effectively guide conservation efforts (A. Danet, 2017) [START_REF] Danet | Interactions entre plantes dans un contexte de communauté : une approche expérimentale en Espagne et en Bolivie[END_REF] . This is why this research was carried out in western Burkina Faso in order to study the methods of sustainable management of Ceiba pentandra (L.) Gaertn through improved knowledge of the species.

Research Methodology

The area of this investigation is the province of the Banwa. It is one of the 6 provinces of the Boucle du Mouhoun region (map 1).

Map 1: The Banwa province location map

Covering an area of 5,888 km2, the Banwa province is located in the northwest of Burkina Faso between the geographical coordinates 3°25' and 4°35' west longitude and 11°45' and 13°45' north latitude (National Soil Office, 2003) [START_REF]Morphopedological study of the provinces of Mouhoun and Balé[END_REF] . The Banwa province is made up of the communes of Solenzo, Sami, Sanaba, Balavé, Tansila and Kouka, and is entirely located in the southern Sudanese climatic sub-zone of Burkina Faso. There are 2 seasons there. The rainy season from May to October, with average monthly temperatures varying between 25°C and 28°C. The dry season from November to April marked by the harmattan. It is characterized on the one hand by a dry and cold wind with low temperatures (around 25°) from November to the end of January and on the other hand by a dry and hot wind with high average monthly temperatures often exceeding 40°C. from March to April. Precipitations, which vary from 700 to 1000 mm per year, is irregular and poorly distributed in space. Hydrographically, the province of the Banwa has a very dense hydrographic network, especially in its western side. The hydrographic network falls within the watersheds of the Mouhoun River and the Kossi River. It is a fairly uneven area. The relief is quite monotonous and altitudes rarely exceed 360m (R. Kissou and al.,2003) [START_REF] Kissou | Morpholopedological study of the provinces of Kossi and Banwa scale 1/100000[END_REF] . Regarding the sampling and data collection, a prospecting study was carried out in order to identify the localities which shelter the populations of the species studied. For the other stages, it consisted in listing the settling or isolated stands of the species in each concerned locality, delimiting the areas of influence of the settlement of the species, identifying resourceful people likely to help establish contacts with the inhabitants having knowledge on the species in the various concerned localities. The inventory method used is the exhaustive enumeration or count of the trees of the species in the different localities of the province where it is represented. The main data collected relate to the identity of the respondent, the respondent's knowledge of the species and the local strategies developed for the sustainability of the species. For the forest management officials and the town halls of the municipalities concerned, the specific information collected focused on bad practices related to the exploitation of the species, the actions carried out for the management of this resource and the proposals to ensure its sustainable management. Thus, in the field, 3 types of data were collected: The dendrometric variables: on each foot reaching the minimum pre-count circumference pre-fixed at 15 cm measured at 1.30 m above the ground (C1.30 m), the following variables were noted: The trunk circumference at 1.30 m above the ground, the total height of the individual, the height of the bole, the radii of the crown (figure 1); Source: realized by the author Legend: N=North, NE=North East, E=east, SE=South East, S=south, SW=South West and =West  Cartographic data: the geographical coordinates of each foot identified were recorded by GPS. This made it possible to generate the locations of the feet of the species on the base maps of the province of the Banwa and its municipalities;  Data on regeneration: natural regeneration is considered to be the set of processes that ensure the restoration of plant populations as old individuals disappear (A. Thiombiano,2005) [START_REF] Thiombiano | Combretaceae of Burkina Faso: taxonomy, ecology and regeneration of species[END_REF] . Plants whose diameter at 1.30 m is less than 5 cm are considered young plants and therefore taken into account in regeneration (B. Belem, 2009) [START_REF] Belem | Ethnobotany and conservation of Bombax costatum pel & vuil. (False kapok tree) in the agricultural production systems of the Central Plateau, Burkina Faso[END_REF] . As part of the study, it was a question of exhaustively counting the subjects of the regeneration.

Descriptive data of the physical environment were also collected, particularly the texture of the soil, which made it possible to determine the types of soil preferred by Ceiba pentandra (L.) Gaertn in the study area. The health status of each plant and the type of the existing land occupation were also recorded.

Regarding data analysis, data from the forest inventory were entered and processed with Excel. It allowed the synthesis of the data in tables, the calculations and finally the realization of the illustration graphs. The parameters that have been calculated from the collected and encoded data are:

The average height of individuals of the species by municipality. The formula used is:

=average height n=number of trees measured in the municipality; hi=height per foot i of the measured species in the municipality.

The average diameter of the subjects of the species per municipality: The formula applied is: =average diameter of feet of the species per municipality n=number of feet measured of the species in the municipality; di=diameter of the individual i of the species.

The basal area: it corresponds to the surface of the horizontal section of the stems measured at 1.30 m above the ground. The average basal area of the feet of the species per municipality was calculated using the following formula:

= average basal area of plants per municipality n=number of foot of the species in the municipality: with di=diameter of the individual i of the species identified in the considered municipality.

In the case of n rays (8 rays in the context of this study), the surface of the horizontal projection of the crown on the ground was determined from the formula for calculating the quadratic mean (J. Pardé & J. Bouchon, 1988; F. Cailliez, 1980) [16,[START_REF] Cailliez | Estimation of volumes and growth of forest stands with particular reference to tropical forests[END_REF] :

Sp=Surface the horizontal projection of the crown on the ground; n = the number of rays of the measured crown;

From the previous formula, the (average) diameter of the crown (doc) is deduced as follows (J. Rondeux, 1993) [START_REF] Rondeux | The measurement of trees and forest stands[END_REF] :

The average density of the feet of the species per municipality was calculated by the following formula:

The regeneration rate (RR): the state of regeneration is an index of the capacity of the forest ecosystem to reconstitute itself. The rate of regeneration of the species by municipality was calculated by the formula of H. Poupon (1980) [START_REF] Poupon | Structure and dynamics of the ligneous stratum of a Sahelian steppe in northern Senegal[END_REF] :

The total stand size includes both young plants and adult plants.

The interpretation of the value of the different regeneration rates calculated from the study data was carried out according to P. Rothé (1964) [START_REF] Rothé | Regeneration in tropical forest. Dipterocarpus drey (Dau) on the Cambridgian side of the Gulf of Siam[END_REF] . For this author:  If the regeneration rate is less than 100%, the species has regeneration difficulties;  If the regeneration rate is between 100 and 1000%, the regeneration is good;  If the regeneration rate is greater than 1000%, the regeneration is very good.

The methodological approach presented in this part made it possible to obtain results.

Research Results

The results of the study deal on the one hand with the spatial analysis of the population and dendrometric characteristics and, on the other hand, with the state of regeneration of Ceiba pentandra (l.) Gaertn and local conservation strategies.

Spatial analysis of the stand and dendrometric characteristics

Regarding the spatial analysis of the settlement, a total of 688 feet distributed in the 6 communes of the Banwa province were counted (map 2).

Map 2: Spatial distribution of individuals of Ceiba pentandra (L.) Gaertn in Banwa province

The municipalities with the highest number of Ceiba pentandra (L.) Gaertn plants are Solenzo (325 plants) and Balavé (103 plants). Concerning the settlement of the species, they are more represented in the municipalities of Solenzo and Sanaba with respectively 26 and 7 settlements of the species. Thus, Ceiba pentandra (L.) Gaertn is sufficiently well distributed in the province. This cast is random.

Concerning the dendrometric characteristics, the curve of distribution of the number of feet of the species according to the classes of the retained diameter, presents the pace (figure 2). The adjustment curve of the distribution of the number of feet according to the height classes has a "bell" shape (figure 3). As for the dendrometric characteristics of the population, they are presented in Table 1.

Source: field works

Source: field works

Table 1: dendrometric characteristics of the population of ceiba pentandra (l.) Gaertn in the study area. The results of the current research show that the average heights of Ceiba pentandra (L.) Gaertn in the province vary between 30 and 39 m. As for the other dendrometric parameters, the municipality of Solenzo has the highest mean diameter. In addition to the results related to the spatial analysis of the settlement and dendrometric characteristics, this study highlights the state of regeneration of Ceiba pentandra (l.) Gaertn and local conservation strategies.

Parameters

State of regeneration of the Ceiba pentandra (L.) Gaertn and local conservation strategies

Concerning the state of regeneration of Ceiba pentandra (L.) Gaertn, the results of the study reveal that the regeneration rate of the species is low. The numbers by height class are presented in table 2. The regeneration rate of the species is 1.60%. The few rare regeneration subjects identified are located in the height class greater than 175 cm (total height >175 cm). As for local conservation strategies, the respondents about the regeneration strategy for the species in their locality have converging points of view. For 89.14% of those respondents, the reproduction methods of Ceiba pentandra (L.) Gaertn are natural regeneration, while for 18.35%, the direct sowing of seeds of the species is better indicated as a silvicultural technique to renew the repopulation of the species. Some factors were mentioned by the respondents to explain the disappearance of the species. Among these factors are the aging of the species' feet (63.67%), the rainfall deficit (41.75%), the lack of maintenance of the species' feet (24.72%), the attacks of parasites (14.60%), the low level of introduction of the species in reforestation operations (13.48%), increasing demography (9.36%), the action of certain types of invading birds such as Bubalornis albirostris and Turtur afer (8.23%). The first, through its defections charged with certain chemical substances and the second which carries parasitic plants (Tapinanthus sp.), make individuals of the species more vulnerable.

Source: filed works

Photo 1: shows a plant of Ceiba pentandra (L.) Gaertn parasitized by Tapinanthus sp.

In the specific case of increasing demography, this factor induces the clearing of new land and the construction of buildings which, in certain cases, are accompanied by the destruction of the feet of the species. The respondents consider that demography is one of the causes of the disappearance of the species in the study area. To ensure the conservation of the species, the local forest authority carry out awareness campaigns for the populations. The themes developed relate to the ecological role played by the species (49.81%), the application of regulatory provisions prohibiting the cutting of the species (37.08%), the preservation of the feet of the species in the agroforestry parks (home fields), the protection against bush fires (23.58%), the ban on debarking the species without the authorization of customary chiefs (11.23%) and fencing (photo 2) young plants with wooden grids (10.49%).

Source: filed works

Photo 2: Wood fence for a young foot of Ceiba pentandra (L.) Gaertn in the village of Gnoumakuy, in the municipality of Sanaba In addition to these actions and given the threats to the species, people believe that special attention should be given to its conservation. They suggest the following solutions: the reforestation of the species (79.03%), the strengthening of public awareness for the protection of the species (61.42%), the production of the species in nurseries (32.20%), the protection of young plants of the species by wire netting (34.83%).

Discussion over the results

The discussion focuses on the shaping of the landscape and the risks associated with the weak regeneration of the species and the local strategy which is not proportional to the risk of extinction of the species. In terms of the shaping the landscape, in the study area, the feet of Ceiba pentandra (L.) Gaertn are remarkable for their large size. They play a big role in the shaping of the local landscapes. The values of the various dendrometric parameters such as the average height, the average diameter and the average basal area make it possible to demonstrate this. Indeed, the results of this study show that the average height of individuals is 30.35m. It is close to the value of 30.76 m, obtained by Y. Tessi and al. (2012) [START_REF] Tessi | Structural and ecological characteristics of populations of Antiaris toxicaria (Pers.) Lesch and Ceiba pentandra (L.) Gaertn in relict forests of southern Benin[END_REF] on the populations of Ceiba pentandra (L.) Gaertn in the relict forests of southern Benin. The curve of the vertical structure has the shape of a "bell". The stems of the future are less numerous to ensure the renewal of the population. Species faithful to this type of distribution in natural forests are said to be destructuring; they are threatened with extinction in the settlements (N. Sokpon & S. Biaou, 2015) [START_REF] Sokpon | The use of diameter distributions in sustained-use management of remnant forests in Benin: case of Bassila forest reserve in North Benin[END_REF] . The horizontal structure of the populations of Ceiba pentandra (L.) Gaertn, shows a numerical superiority of the large subjects. There is a total absence of individuals of the species in the lower classes. The species is getting older with diameters at 1.30 m above the ground reaching 300 cm. According to A. Ouedraogo (2006) [START_REF] Ouedraogo | Sexual regeneration of Boswellia dalzielii Hutch., a valuable medicinal tree in Burkina Faso[END_REF] , the aging of the settlements is illustrated by the low proportion of individuals in small classes. In contrast, other studies have shown a relatively stable diameter structure of Ceiba pentandra (L.) Gaertn settlements in relict forests in southern Benin (Y. Tessi and al., 2012, op.cit.) [START_REF] Tessi | Structural and ecological characteristics of populations of Antiaris toxicaria (Pers.) Lesch and Ceiba pentandra (L.) Gaertn in relict forests of southern Benin[END_REF] . The results obtained by K. Adjonou (2016) [START_REF] Adjonou | Consideration of structural characteristics as ecological indicators of forest management in Togo (West Africa)[END_REF] , indicate for the species a maximum diameter of 152.9 cm, measured as part of a study on forest management in Togo. This value is comparable to that obtained by the current study which is 145cm. The density of Ceiba pentandra (L.) Gaertn settlements varies between 10 to 72 trees/ha in the communes of the study area. These results are comparable to those of I. Guimbo (2010) [START_REF] Guimbo | Stocking of parks in Neocarya macrophylla (Sabine) Prance et à Vitellaria paradoxa (Gaertn. C.F.) in southwestern Niger: diversity, structure and regeneration[END_REF] . This source notes a density of 25 Ceiba pentandra trees in a study of Neocarya macrophylla (Sabine) Prance and Vitellaria paradoxa (Gaertn. C.F.) parklands in southwestern Niger.

Risk related to the weak regeneration of the species and the local strategy which is not proportional to the risk of disappearance of the species

Regarding the risk related to the low regeneration of the species, the regeneration rate of Ceiba pentandra (L.) Gaertn in the province of Banwa is low. This reveals a lack of rejuvenation of its settlements. Many factors influence the regeneration and the selection in the adult settlement. F. Russell & N. Fowler (2002) specify that these factors are, among others, low seed production, fruit predation, grazing, bush fires, light under the canopy and climate variability. The poor natural regeneration of species is often mentioned as a consequence of the shortage of seeds (J. Weber and al., 2008; F. Bognounou, and al.,2010) [START_REF] Weber | Growth and survival of Prosopis africana provenances tested in Niger and related to rainfall gradients in the West African Sahel[END_REF][START_REF] Bognounou | Regeneration of five Combretaceae species along a latitudinal gradient in Sahelo-Sudanian zone of Burkina Faso[END_REF] . Regarding the local strategy which is not proportional to the risk of extinction of the species, the population of the species is highly disturbed. Excessive harvesting of timber and non-timber forest products is a danger to the sustainability of the species. According to A. Lykke and al. (2004) [START_REF] Lykke | Valuation of the local dynamics of 56 woody species in the Sahel[END_REF] ; O. Lougbégnon and al. (2011) [START_REF] Dossou | Etude ethnobotanique des ressources forestières ligneuses de la forêt marécageuse d'Agonvè et terroirs connexes au Bénin[END_REF] ; M. Dossou and al., 2012) [] , the importance given to a species does not depend on its availability but on its ability to meet the needs of populations in the different categories of use. The leaves and bark of Ceiba pentandra (L.) Gaertn are used by people for various purposes. Excessive harvesting leaves can impact fruiting; also abusive debarking can promote the attack of individuals of the species by fungi, malformation of the trunk. As a result, these local practices developed by the populations of the study area vis-à-vis the species do not guarantee the sustainability of this resource. However, the local strategies implemented for the rehabilitation of the species are not adapted to the danger it faces.

Conclusion

This research carried out in the west of Burkina Faso is an analysis of the methods of sustainable management of Ceiba pentandra (L.) Gaertn through improved knowledge of the species. This study made it possible, on the one hand, to highlight the spatial analysis of the population and the dendrometric characteristics of the species. This species participates in shaping the landscape in the study area because the feet of Ceiba pentandra (L.) Gaertn are remarkable for their large size and the values of the various dendrometric parameters such as the average height, the average diameter and the average surface burrow demonstrate this. On the other hand, the study highlights the state of regeneration of Ceiba pentandra (L.) Gaertn and local conservation strategies. Regarding the risk related to the low regeneration of the species, its regeneration rate in the Banwa province is low. This situation reflects a lack of rejuvenation of its settlements. And as for the local strategy which is not proportional to the risk of disappearance of the species, the population of the species is strongly disturbed. Excessive harvesting of timber and non-timber forest products constitutes a danger to the sustainability of the species because the local practices developed by the populations of the study area vis-à-vis the species do not guarantee the sustainability of this resource. In addition, the local strategies implemented for the rehabilitation of the species are not adapted to the danger it faces.

Fig 1 :

 1 Fig 1: the locations of the 8 combs measured at the crown of each inventoried tree

Fig 2 :

 2 Fig 2: Horizontal population structure of Ceiba pentandra (L.) Gaertn in Banwa province As shown in Figure 2, the population of Ceiba pentandra (L.) Gaertn includes a third of tall subjects that can exceed 200 cm. There is also a concentration of staff between the classes [65-85[ and [185-205[. The class [25-45[is the class with the least number of employees.Figure 3 shows the vertical population structure of Ceiba pentandra (L.) Gaertn in Banwa province.

Fig 3 :

 3 Fig 3: Vertical population structure of Ceiba pentandra (L.) Gaertn in the Banwa province

Table 2 :

 2 Number of regeneration per height class (cm)

	Height class in cm	Numbers	Proportion in %
	]0-25]	1	9,09
	]50-75]	1	9,09
	]75-100]	2	18,18
	]100-125]	1	9,09
	>175	6	54,55
	Total	11	100
	Source: field works


Melissa Liborio Zapata
email: melissa.liborio-zapata@univ-smb.fr

Lamia Berrah

Laurent Tabourot

Towards the definition of an Impact Level factor of SME features over Digital Transformation

Keywords: Industry 4.0, Digital Transformation (DT), Small and Medium Enterprises (SMEs), Impact Analysis, Impact level Performance Indicator

Companies are experimenting change at a fast pace in the business environment due to the evolution of technology. As a result, they require solution approaches designed to guide their Digital Transformation (DT) efforts. However, several factors must be considered in their design, notably how the particular features of companies impact positively or negatively their DT. In the case of Small and Medium Enterprises (SMEs) in manufacturing, this is particularly relevant, as their vulnerabilities, such as the lack of resources, seem to have a significant impact over the success of DT initiatives. Defining this impact as an indicator of this effect will provide valuable information to control the DT to better achieve its objectives. For this reason, the aim of this paper is to introduce the impact level performance indicator for the specific scenario of manufacturing SMEs' DT. An Impact Analysis is presented with this purpose using a qualitative approach. Conclusions of this work lead to further develop the Impact Level indicator using a quantitative approach that enables its use in the control of the DT process.

Introduction

Just some years ago, a company could have periods of stability only interrupted by a few radical changes that required immediate action in order to remain competitive [START_REF] Brown | The Art of Continuous Change: Linking Complexity Theory and Time-Paced Evolution in Relentlessly Shifting Organizations[END_REF]. Nowadays, change is constant and the evolution of technology is an important reason behind its speed [START_REF] Kagermann | Recommendations for implementing the strategic Initiative Industrie 4.0[END_REF]. New digital technologies as Artificial Intelligence, along with other trends such as faster Internet service, represent many opportunities for companies searching to lower costs by improving performance or capturing new income by creating value through new products and services [START_REF] Lichtblau | IMPULS Industrie 4.0 Readiness[END_REF]. Despite the advantages, companies also face critical challenges in the implementation of these new technologies [START_REF] Kagermann | Recommendations for implementing the strategic Initiative Industrie 4.0[END_REF]. In this context, a Digital Transformation (DT), defined as "the use of new digital technologies to enable major business improvements" [START_REF] Fitzgerald | Embracing digital technology: a new strategic imperative[END_REF], has become the goal for every company.

Programs like Industry 4.0, born in Germany in 2011 [START_REF] Schuh | Industrie 4.0 Maturity Index. Managing the Digital Transformation of Companies[END_REF], and other initiatives in research and practice, are looking for the right approach to succeed in this transformation.

Numerous frameworks and models are also proposed to assist companies of all sizes and sectors with their efforts [START_REF] Mittal | A critical review of smart manufacturing & Industry 4.0 maturity models: Implications for small and medium-sized enterprises (SMEs)[END_REF][START_REF] Schumacher | A maturity model for assessing Industry 4.0 readiness and maturity of manufacturing enterprises[END_REF][START_REF] Akdil | Maturity and readiness model for industry 4.0 strategy[END_REF]. However, the DT process is highly complex, not only because it involves changes in many business dimensions [START_REF] Verhoef | Digital transformation: A multidisciplinary reflection and research agenda[END_REF], but also because the degree of the complexity that companies will face depends on their specific situation [START_REF] Lichtblau | IMPULS Industrie 4.0 Readiness[END_REF]. Companies, therefore, need to know how their particular features impact positively or negatively their approach of the DT process and the achievement of the associated objectives.

The answer is highly relevant for Small and Medium Enterprises (SMEs), companies with a set of characteristic features related to their size that make them seem vulnerable in the face of a DT [START_REF] Schumacher | A maturity model for assessing Industry 4.0 readiness and maturity of manufacturing enterprises[END_REF][START_REF] Akdil | Maturity and readiness model for industry 4.0 strategy[END_REF][START_REF]European SME Action Programme[END_REF]. Features, like the lack of financial resources to invest in the new technologies or the human resources with the right skills to implement them, are at the source of those vulnerabilities [START_REF] Lichtblau | IMPULS Industrie 4.0 Readiness[END_REF]. Defined by the European Commission as companies with a staff of only 250 people or less [START_REF]European Commission: What is an SME[END_REF], SMEs, despite their size, hold great importance as a group, as they account for more than 99% of the businesses in Europe [START_REF]European SME Action Programme[END_REF]. Consequently, their success is a source of economic growth for the region and their DT is considered as an important avenue to achieving it [START_REF]European SME Action Programme[END_REF]. Inside the SMEs category, the DT of those in manufacturing is particularly crucial, as they are not only the users but the producers of the new digital technologies. They are also a critical part of supply chains of Business to Business markets that have already started their digitalization process and are demanding the same from their supply chain participants [START_REF] Khurana | The Future of Manufacturing -France[END_REF].

Given the background, the quantification of the level of impact that manufacturing SMEs features have over the DT is critical in controlling the process and the achievement of its objectives. For this reason, the concern of this work is the introduction of the impact level as an indicator to be used by decision-makers in SMEs with this purpose. To start its development, the aim of this paper is to present the impact level using a qualitative approach that shows its general behaviour. Therefore, the organization of the paper is as follows. In Section 2, a brief description of the dimensions of a DT are presented, along with the specific features that characterized manufacturing SMEs. This information is followed by the qualitative analysis of the impact level in Section 3. In Section 4, feedback from France industry experts regarding the analysis is shared. Finally, conclusions are proposed in Section 5, along with the perspectives towards the further development of the Impact Level performance indicator using a quantitative approach.

2

Digital Transformation and Manufacturing SMEs elements

DT dimensions

Solution approaches for DT, in research and practice, propose each a set of business dimensions or aspects that experiment change during the transformation process. Once focused only on the technological side of the change, current works understand the need to have a broad business perspective of the process [START_REF] Schumacher | A maturity model for assessing Industry 4.0 readiness and maturity of manufacturing enterprises[END_REF]. However, no consensus has been reached regarding the specific dimensions that must be included, as some works choose a broad and general scope [START_REF] Schumacher | A maturity model for assessing Industry 4.0 readiness and maturity of manufacturing enterprises[END_REF], others focus mostly on the operational [START_REF] Akdil | Maturity and readiness model for industry 4.0 strategy[END_REF] or technological [START_REF] Lichtblau | IMPULS Industrie 4.0 Readiness[END_REF] aspects of the transformation. In consequence, to define a set of dimensions for this work, the following procedure was performed. 1. A literature review was conducted and 21 DT models were identified.

2. An evaluation of the models according to the design principles proposed by Pöppelbuß [START_REF] Pöppelbuß | What makes a useful maturity model? A Framework of General Design Principles for Maturity Models and its Demonstration in Business Process Management[END_REF], resulted in the selection of the top 7. 3. A comparative analysis of the different dimensions proposed by the 7 models [START_REF] Lichtblau | IMPULS Industrie 4.0 Readiness[END_REF][START_REF] Schuh | Industrie 4.0 Maturity Index. Managing the Digital Transformation of Companies[END_REF][START_REF] Schumacher | A maturity model for assessing Industry 4.0 readiness and maturity of manufacturing enterprises[END_REF][START_REF] Akdil | Maturity and readiness model for industry 4.0 strategy[END_REF][START_REF] Geissbauer | Industry 4.0: Building the digital enterprise[END_REF][START_REF] Lee | A smartness assessment framework for smart factories using analytic network process[END_REF][START_REF] Scremin | Towards a framework to assess the maturity for Industry 4.0 adoption in manufacturing companies[END_REF] was performed. 4. A proposal of a set of business dimensions affected by a DT was created based on the ones most mentioned by the selected models. This proposal shares a view of the wide scope of the changes involved during a DT.

Features of Manufacturing SMEs

Manufacturing SMEs possess a set of particular characteristics that define their behaviour. Their specific features are enlisted to better understand their particular conditions when they are faced with challenges such as a DT. The definition used in this work (Table 2) is based on a previous research work that assembled a list of their features as a result of a literature review on the subject [START_REF] Mittal | A critical review of smart manufacturing & Industry 4.0 maturity models: Implications for small and medium-sized enterprises (SMEs)[END_REF]. The following set F of the ten features fi, i{1,2,3,4,5,6,7,8,9,10}, conceptualize manufacturing SMEs as companies with low availability of resources and a strong focus on the performance of day-to-day operations.

Impact Analysis

The proposed approach is to assess, through a qualitative analysis, the level of impact of the effect that SMEs features have over the DT dimensions, based on the theoretical definition of these two elements, respectively, presented in Table 1 and Table 2. For the purposes of this work, the Impact Level ILij is conceptualized as a performance indicator that shows the level of the positive or negative effect that a given feature fi has over a given dimension dj. Therefore, ILij can be defined as the set I and as the result of the following function:

ImpLev : F x D  I (fi,dj) ImpLev (fi,dj) = ILij
The objective of this analysis is to understand the nature and intensity of the Impact Level ILij using the given set of SMEs features defined by their current stereotypical characterization. This approach provides a point of departure to draw the preliminary conclusions towards the development of the ILij as a numerical value.

Methodology

In order to generate the required information for the analysis, a matrix was built with the individual qualification of the impact level of all the possible combinations between features fi and dimensions dj. This qualification was performed with a 4-level scale composed by 2 criteria, an intensity of the impact, Low "L" or High "H" and a sense of this impact, Positive "+" or Negative "-". The 4 levels are described as follows.

 L+: Low influence of the feature in support of the change in the dimension.  L-: Low influence of the feature against the change in the dimension.  H+: High influence of the feature in support of the change in the dimension.  H-: High influence of the feature against the change in the dimension.

The qualification of ILij is based on the state of the art on the subject and validated by experts in the related fields. Additional meetings were held when there were conflicting positions in order to reach a consensus. The analysis was performed by the qualification of both criteria for each combination. For example, it is expected that a Culture with low flexibility for change and experimentation f3 will be a determinant barrier for the design and especially the implementation of the DT Strategy d1, hence its "H-" value, in other words, IL31 = ImpLev (f3,d1) = H-. The combinations that do not relate or present any impact between them were left empty, as a way to maintain the focus on the real issues during a DT.

Impact Analysis

Table 3 presents the qualification of the ILij of the manufacturing SMEs features fi over the DT dimensions dj. General conclusions of the impact analysis are presented from two perspectives. The first one highlights the dimensions where potential issues can arise during the DT, considering the effect of the given features. The second one, on the other hand, shows the features that hold the most critical influence over the dimensions. The management of these conditions could represent a higher success rate of the DT initiatives.

Dimensions Perspective. The analysis considers the following relevant findings.  The dimensions that are more impacted by the features are Strategy d1, Products and Services d5 and Technology d12.  Strategy d1 definition, and particularly its implementation, will challenge almost every feature of SMEs and will require change management tools.

 Technology d5 and the Products and Services d12 that it enables will be the source of the major changes during the DT.  These 3 dimensions will have the advantage of Product development with high levels of customization (f6) and Strong Customer/Supplier Relationships (f8).

Features Perspective. The analysis considers the following relevant findings.  The features that make the strongest impact over the dimensions are Limited resources f1, Culture with low flexibility for change and experimentation f3 and Low investment in R&D and lack of alliances with Universities f9.  Culture with low flexibility for change and experimentation f3 and Limited resources f1 could have a strong impact as they touch most of the DT dimensions.  The Limited resources f1 of all sorts will affect all the dimensions that need them in order to achieve the necessary changes required by the DT.  The Low investment in R&D and lack of alliances with Universities f9 will demand a significant effort to implement a culture of innovation, crucial in a DT.  Only 2 features have a positive effect: Product development with high levels of customization f6 and Strong Customer/Supplier Relationships f8.

The results of the analysis are not completely surprising as it confirms the disadvantaged position of SMEs in front a DT challenge, but the global view of the ILij reveals in detail a degree of magnitude of the effect between features and dimensions that it was not evident at the beginning of this work. From this insight, numerous possibilities arise to deepen the understanding of the relationship between them, like, for example, the variations in the ILij with different configurations of SME features (e.g., a more formal structure, a culture more open to change). As patterns in the table become evident, it becomes clear that the development of this indicator could provide the information to design a DT experience more consistent with the Manufacturing SMEs scenario.

Once collected the necessary insight through this qualitative approach, the next stage of this research will focus on translating this information into a numerical model using a quantitative approach to calculate a more accurate performance expression of the ILij. The model will provide a quantification of the "High" and "Low" levels in different scenarios and conditions, taking into account the specific factors that define the magnitude of the effect of the features over the dimensions. A model of these characteristics will enable the simulation of different scenarios and, in consequence, will support decision-making when managing DT initiatives, facilitating the achievement of its objectives.

Industry feedback

French manufacturing industry holds a leadership position in Europe [START_REF] Khurana | The Future of Manufacturing -France[END_REF], however as it happens with many sectors of the economy, in order to boost their growth, the digitalization of manufacturing SMEs is a priority for the region [START_REF]European SME Action Programme[END_REF]. Accordingly, competitiveness clusters as Mont-Blanc Industries in the French region of Auvergne-Rhône-Alpes, are active in promoting their DT with the participation of a network of universities and other industry actors [START_REF]Mont-Blanc Industries Homepage[END_REF]. As this research work is focused on the participants of this region, a series of interviews were conducted with industry experts to discuss the outcome of the impact analysis, as well as the list of SME features and DT dimensions to verify if those elements correspond to the reality of the sector.

The industry experts confirmed that the findings issued from the analysis make sense according to their practice. They recognize that the limitation of resources is a big issue, but not as big as the type of leadership in the organization that, in their opinion, defines their organizational culture. Often they also see that some types of leadership, present in family-owned SMEs, are a strong barrier to pursue a DT due to a poor vision of the future and lack of willingness to risk their still comfortable positions. These remarks are also consistent with the general characterization of SMEs as companies focused on managing day-to-day operations.

Finally, in addition to their comments regarding the results of the analysis, industry experts stressed the importance to keep in mind that the generalization regarding the manufacturing SME features could not apply to manufacturers in all sectors, as the ones in the automotive and aerospace sectors seem to have a different characterization. Companies in those sectors, as well as those who already started their DT, may have a different level of maturity in their features as a consequence of the changes implemented during their transformation process or because of pressures of their specific environment. This relevant feedback confirms the vision of the design of the future quantitative model that considers the building of a model flexible enough to adapt to the different situations and conditions of manufacturing SMEs.

Conclusions and Perspectives

Digital Transformation describes the efforts of the enterprises that want to take advantage of digital technologies to improve their competitive position. However, benefits do not come easy, as the speed in the evolution of these technologies is turning the economic landscape in one full of challenges, especially for manufacturing SMEs. This type of company is struggling to transform, due in theory to the vulnerabilities related to their characteristic features. The contribution of this paper, therefore, is focused on understanding the effect that their features have over the business dimensions of a DT in order to use this insight to improve the success of this process. Relevant findings include the identification of Strategy d1 and Culture f3 as the top critical dimension and feature, respectively. But beyond the obvious, the value of this research is focused on the insight that a global view of the 1 to 1 interaction between features and dimensions provide for the study of the impact level as a performance indicator of the success of a DT. This preliminary work on the subject will be followed by a more in-depth study of the dynamics of the impact between features and dimensions to get the necessary information to translate it into a quantitative approach that provides a model that guides decision-makers to a successful DT. This model will be part of the efforts of a research project whose main objective is to provide manufacturing SMEs in France with a DT framework.

Table 1

 1

presents the set D of the 12 dimensions dj, j{1,2,

[START_REF] Lichtblau | IMPULS Industrie 4.0 Readiness[END_REF][START_REF] Fitzgerald | Embracing digital technology: a new strategic imperative[END_REF][START_REF] Schuh | Industrie 4.0 Maturity Index. Managing the Digital Transformation of Companies[END_REF][START_REF] Mittal | A critical review of smart manufacturing & Industry 4.0 maturity models: Implications for small and medium-sized enterprises (SMEs)[END_REF][START_REF] Schumacher | A maturity model for assessing Industry 4.0 readiness and maturity of manufacturing enterprises[END_REF][START_REF] Akdil | Maturity and readiness model for industry 4.0 strategy[END_REF][START_REF] Verhoef | Digital transformation: A multidisciplinary reflection and research agenda[END_REF][START_REF]European SME Action Programme[END_REF][START_REF]European Commission: What is an SME[END_REF]

,12}, proposed by this work with a brief description of the changes expected in each of them during a DT.

Table 1 .

 1 DT dimensions.

	ID Dimension	Expected Changes
	d1	Strategy	Digital Strategy definition and implementation
	d2	Business Models	Innovation of the organization's value proposition
	d3	Investment	Planning related to the realization of the Digital Strategy
	d4	Customer	Digital Experience definition
	d5	Products and Services	Creation of Smart and Connected Products and Services
	d6	Business Process	Processes creation, redesign and automation
	d7	Culture	Change towards Innovation and Collaboration
	d8	Organizational Structure Flexibility, Agility and Cross-functional Collaboration
	d9	Leadership	Leaders aware and prepared for the Digital Era
	d10 (Strategic) Partnerships	Collaboration with customers and competitors
	d11 Employee Competences Digital Competences
	d12 Technology	Digital Technologies selection and implementation

Table 2 .

 2 Manufacturing SMEs features.

	ID Feature
	f1	Limited resources (financial, technical, human)
	f2	Organizational Structure less complex with informal strategy & decision making
	f3	Culture with low flexibility for change and experimentation
	f4	Personnel engaged in multiple domains of the organization
	f5	Low regard for business processes and standards
	f6	Product development with high levels of customization
	f7	Industry Knowledge focused in a specific domain
	f8	Strong Customer/Supplier Relationships
	f9	Low investment in R&D and lack of alliances with Universities
	f10	Low adoption of new technologies

Table 3 .

 3 Impact analysis of DT dimensions vs. Manufacturing SMEs features.

	Dimension/	f1	f2	f3	f4	f5	f6	f7	f8	f9	f10
	Feature
	d1	H-	H-	H-		H-	H+	H-	H+	H-	H-
	d2			H-	H-			H-	L+
	d3	H-	H-	H-				H-		H-	H-
	d4	H-		H-		H-			H+	H-	H-
	d5	H-		H-	H-		H+	H-	H+	H-	H-
	d6	H-	H-	H-	H-	H-		H-	H+
	d7	H-		H-	L+				H+	H-	H-
	d8	H-	H-	H-	L-
	d9	H-	H-	H-
	d10		H-	H-					H+	H-
	d11	H-		H-	H-			H-		H-	H-
	d12	H-	H-	H-			H+	H-	H+	H-	H-

Acknowledgments. The financial support from CONACYT (Grant 707990) is gratefully acknowledged.