检索结果-南通市图书馆

Solution Concepts and New Optimality Conditions in Bilevel Multiobjective Programming

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Applied Mathematics 2012年第10期3卷 1395-1402页

作者： Francisque Fouodji Dedzo laure pauline fotso Calice Olivier Pieume Department of Computer Sciences Faculty of Science University of Yaoundé I Yaoundé Cameroon Department of Mathematics Faculty of Science University of Yaoundé I Yaoundé Cameroon Regional Bureau for Education in Africa Pole de Dakar UNESCO Dakar Senegal

In this paper, new sufficient optimality theorems for a solution of a differentiable bilevel multiobjective optimization problem (BMOP) are established. We start with a discussion on solution concepts in bilevel multiobjective programming;a theorem giving necessary and sufficient conditions for a decision vector to be called a solution of the BMOP and a proposition giving the relations between four types of solutions of a BMOP are presented and proved. Then, under the pseudoconvexity assumptions on the upper and lower level objective functions and the quasiconvexity assumptions on the constraints functions, we establish and prove two new sufficient optimality theorems for a solution of a general BMOP with coupled upper level constraints. Two corollary of these theorems, in the case where the upper and lower level objectives and constraints functions are convex are presented.

关键词： Bilevel Multiobjective Optimization Multiobjective Optimization Sufficient Optimality Condition Strict Convexity Pseudoconvexity Quasiconvexity

Generating Efficient Solutions in Bilevel Multi-Objective Programming Problems

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

American Journal of Operations Research 2013年第2期3卷 289-298页

作者： Calice Olivier Pieume Patrice Marcotte laure pauline fotso Patrick Siarry Department of Computer Science and Operations Research University of Montreal Montreal Canada Department of Computer Sciences Faculty of Science University of Yaoundé I Yaoundé Cameroon Department of Mathematics Faculty of Science University of Yaoundé I Yaoundé Cameroon LISSI Faculty of Sciences and Technology University of Paris XII Val-de-Marne Créteil France

In this paper, we address bilevel multi-objective programming problems (BMPP) in which the decision maker at each level has multiple objective functions conflicting with each other. Given a BMPP, we show how to construct two artificial multiobjective programming problems such that any point that is efficient for both the two problems is an efficient solution of the BMPP. Some necessary and sufficient conditions for which the obtained result is applicable are provided. A complete procedure of the implementation of an algorithm for generating efficient solutions for the linear case of BMPP is presented. A numerical example is provided to illustrate how the algorithm operates.

关键词： Multi-Objective Programming Bilevel Programming Efficient Solution Efficient Edge Hierarchical Systems

Energetic Extended Edge Finding Filtering Algorithm for Cumulative Resource Constraints

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

American Journal of Operations Research 2013年第6期3卷 589-600页

作者： Roger Kameugne Sévérine Betmbe Fetgo laure pauline fotso Department of Computer Sciences Faculty of Sciences University of Yaounde I Yaoundé Cameroon Department of Mathematics Higher Teachers’ Training College University of Maroua Maroua Cameroon Department of Mathematics Faculty of Sciences University of Yaounde I Yaoundé Cameroon

Edge-finding and energetic reasoning are well known filtering rules used in constraint based disjunctive and cumulative scheduling during the propagation of the resource constraint. In practice, however, edge-finding is most used (because it has a low running time complexity) than the energetic reasoning which needs O(n3) time-intervals to be considered (where n is the number of tasks). In order to reduce the number of time-intervals in the energetic reasoning, the maximum density and the minimum slack notions are used as criteria to select the time-intervals. The paper proposes a new filtering algorithm for cumulative resource constraint, and titled energetic extended edge finder of complexity O(n3). The new algorithm is a hybridization of extended edge-finding and energetic reasoning: more powerful than the extended edge-finding and faster than the energetic reasoning. It is proven that the new algorithm subsumes the extended edge-finding algorithm. Results on Resource Constrained Project Scheduling Problems (RCPSP) from BL set and PSPLib librairies are reported. These results show that in practice the new algorithm is a good trade-off between the filtering power and the running time on instances where the number of tasks is less than 30.

关键词： Constraint-Based Scheduling Global Constraint Cumulative Resource Energetic Reasoning Edge-Finding Extended Edge-Finding Maximum Density Minimum Slack

Solving Bilevel Linear Multiobjective Programming Problems

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

American Journal of Operations Research 2011年第4期1卷 214-219页

作者： Calice Olivier Pieume Patrice Marcotte laure pauline fotso Patrick Siarry 不详

This study addresses bilevel linear multi-objective problem issues i.e the special case of bilevel linear programming problems where each decision maker has several objective functions conflicting with each other. We introduce an artificial multi-objective linear programming problem of which resolution can permit to generate the whole feasible set of the upper level decisions. Based on this result and depending if the leader can evaluate or not his preferences for his different objective functions, two approaches for obtaining Pareto- optimal solutions are presented.

关键词： Multiobjective Programming Bilevel Programming Feasible Solution Pareto-Optimal Solutions

Dietary Diversity and Food Security Status among Cameroonian Adults Living in Semi-Urban Areas: A Cross-Sectional Study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Food and Nutrition Sciences 2024年第7期15卷 548-564页

作者： Tonou Boris Ronald Tchuente pauline Vervaine Hagbe Eliane Flore Eyenga Kemadjou Ruth Edwige Dibacto Ngassa Dany Joël Ngoumen fotso Janvier Aime Youovop Nguemto Roussel Guy Takuissu Judith laure Ngondi Julius Enyong Oben Department of Biochemistry Faculty of Science University of Yaound 1 Yaound Cameroon Centre for Food Food Security and Nutrition Research Institute of Medical Research and Medicinal Plant Studies Yaound Cameroon Center of Nutrition and Functional Foods Yaound Cameroon

Introduction: Food security is one of the greatest challenges that most African countries face. It is a concept that considers not only food quantity but also food quality. The objective of this study was to describe dietary diversity and food security status at the individual level in Cameroonian populations. Methods: A total of 1180 men and women aged 20 and over and living in the West, North West, and Littoral regions of Cameroon were recruited. Data on dietary habits were collected through the frequency of consumption of various food groups. Dietary diversity was assessed using a 24-hour dietary recall. Food security status was determined by combining two indicators (food consumption score and individual food diversity score). Results: The mean dietary diversity score of the population was 3.53 ± 1.44, p Conclusion: The diet diversity of adults living in the West, North West, and Littoral regions of Cameroon is medium. Although half of the study population was food secure, there is a need to implement food security policies further to reduce food insecurity among the Cameroonian population.

关键词： Dietary Diversity Individual Food Security Littoral West North West Cameroon

Diabetes and Hypertension Are Associated with Food Insecurity in a Cameroonian Population: A Case-Control Study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Biosciences and Medicines 2024年第2期12卷 1-21页

作者： Boris Ronald Tonou Tchuente pauline Vervaine Hagbe Hippolyte Tene Mouafo Janvier Aime fotso Youovop Ousmane Mfopou Mbiondi Javeres Leonel Ntepe Mbah Roussel Guy Nguemto Takuissu Raissa Francoise Ntentie Boris Gabin Kingue Azantsa Judith laure Ngondi Julius Oben Enyong Department of Biochemistry Faculty of Sciences University of Yaounde 1 Yaounde Cameroon Centre for Food Food Security and Nutrition Research Institute of Medical Research and Medicinal Plant Studies Yaounde Cameroon Department of Biosciences COMSATS University Islamabad Islamabad Pakistan Laboratory of Human Metabolism and Non-Communicable Disease Institute of Medical Research and Medicinal Plant Studies Yaounde Cameroon Higher Teacher’s and Training College University of Yaounde 1 Yaounde Cameroon Center of Nutrition and Functional Foods Yaounde Cameroon

Diabetes and hypertension are the most prevalent cardiovascular risk factors. Recent studies showed an increase in the prevalence of food insecurity in our country. The aim of this study was to assess how food insecurity affects the dietary habits, socio-demographic characteristics and metabolic profile of individuals with diabetes or hypertension. This case-control study was conducted among diabetic and hypertensive participants (cases) and diabetic and hypertensive normal (controls) during the screening campaigns for nutrition-related chronic diseases. The sociodemographic, clinical and biochemical parameters of the participants were analyzed. Logistic regression analyses were performed to identify factors associated with diabetes and hypertension in the study population. Bivariate analyses showed that male gender (OR = 1.972;95% CI: 1.250 - 3.089), regular alcohol consumption (OR = 2.012;95% CI: 1.294 - 3.130), low fruit consumption (OR = 1.590;95% CI: 1.016 - 2.488), low dietary diversity (OR = 2.915;95% CI: 1.658 - 5.127) and abdominal obesity (OR = 1.893, CI 95% 1.203 - 2.978) were significantly associated with hypertension. In addition, low fruit consumption (OR = 1.829;95% CI 1.092 - 3.064), low legume consumption (OR = 3.515;95% CI 1.861 - 6.635), and hypertriglyceridaemia (OR = 2.241, 95% CI 1.139 - 4.408) were significantly associated with diabetes. The indirect association observed between food insecurity and diabetes and hypertension suggests the need for nutritional policies aimed at popularizing the production and consumption of fruits and legumes. Similarly, health services need to be aware and informed of the important role that food insecurity can play in the development of diabetes and hypertension.

关键词： Food Insecurity Diabetes Hypertension Cameroon

Disparities in Prevalence and Determinants of Hypertension amongst Bamiléké Adults Residing in Two Different Agroecological Zones of Cameroon

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Open Journal of Epidemiology 2024年第3期14卷 419-443页

作者： Maxwell Wandji Nguedjo Nanhah Kamga Jules Vidal Alice Louise Woguia pauline Vervaine Hagbe David Goda Dany Joël Ngassa Ngoumen Hippolyte Tene Mouafo Boris Gabin Kingue Azantsa Judith laure Ngondi Julius Enyong Oben Department of Biochemistry Faculty of Sciences University of Yaounde I Yaounde Cameroon Laboratory of Epidemiology and Nutritional Status Centre for Food Food Security and Nutrition Research Institute of Medical Research and Medicinal Plant Studies Yaounde Cameroon Department of Pharmacology Faculty of Health Sciences School of Clinical Medicines University of Fee State Bloemfontein South Africa Laboratory Development of Food Technology Centre for Food Food Security and Nutrition Research Institute of Medical Research and Medicinal Plant Studies Yaounde Cameroon

Background: Cardiovascular diseases such as hypertension (HTN) are one of the main causes of death in Cameroon. This study aimed at assessing prevalence disparities and determinants of hypertension amongst Bamiléké adults residing in two different agroecological zones of Cameroon. Methods: A cross-sectional and descriptive survey was conducted among Bamiléké population living in the Highlands zone (Western region) and in the Monomodal Rainforest zone (Littoral region) of Cameroon from August 2016 to August 2017. Participants (962) were aged at least 20 years old. Data on sociodemographic, hemodynamic, anthropometric, and biochemical parameters and lifestyle of the participants were collected. Results: Results obtained revealed that 34.2% were hypertensive and those residing in the highland zone were more affected than those living in the monomodal rainforest zone (44.5% vs 22.9%). The different subtypes of HTN (Isolated systolic hypertension (14.1%), isolated diastolic hypertension (7.2%) and Systo-diastolic hypertension (23.3%)) were also more prevalent in the Highlands Zone. The most prevalent stage of HTN was pre-HTN (31.5%). However, people living in the monomodal rainforest zone were more affected by pre-HTN compared to Bamiléké living in the highland zone (33.6% vs. 29.6%). Results also showed that high consumption (≥ 3 times/week) of carbohydrate- and fat-rich foods, ageing, obesity, and marital status were associated with high blood pressure in both agroecological zones. Besides, secondary education (OR = 0.68;95% CI: 0.42 - 0.99) in the Highlands Zone and high (≥3 times/week) vegetable consumption (OR = 0.66;95% CI: 0.44 - 0.98) in the Monomodal Rainforest Zone had a protective effect on elevated blood pressure of population. Conclusion: There is a disparity in the prevalence of hypertension and some of its determinants among Bamiléké adults residing in different agroecological zones. This work highlights the need to advocate for local and ethno-cultural he

关键词： Hypertension Disparities Determinants Bamiléké Ethnic Group Agroecological Zone

Dietary Diversity and Food Security Status among Cameroonian Adults Living in Semi-Urban Areas: A Cross-Sectional Study

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Towards A “Deep” Ontology for African Traditional Medicine

Food and Nutrition Sciences（食品与营养科学） 2024年第7期 548页

来源：博看期刊评论

在线全文

博看期刊

学校读者我要写书评

暂无评论

Intelligent Information Management 2011年第6期3卷 244-251页

作者： Armel Ayimdji Souleymane Koussoubé laure P. fotso Balira O. Konfé 不详

The increasing interest on ontologies as the backbone technology for knowledge based systems implies the refinement of ontologies development methods. In this paper we propose a new approach to develop an ontology for African Traditional Medicine. The aim of our approach is to build a deep ontology by deepening concepts descriptions to formally represent all the semantics underlying the concepts used in African traditional medicine. We use a description logics language to formalize our approach.

关键词： Primary Ontology Deep Ontology Hidden Aspects Interpretations African Traditional Medicine Description Logics