The Lagrange multipliers and existence of competitive equilibrium in an intertemporal model with endogenous leisure

This paper proves the existence of competitive equilibrium in a single sector dynamic economy with elastic labor supply. The method of proof relies on some recent results (see Le Van and Saglam [2004]) concerning the existence of Lagrange multipliers in infinite dimensional spaces and their representation as a summable sequence.Optimal growth model, Lagrange multipliers, competitive equilibrium, elastic labor supply.

Growth and convergence in a model with renewable and non-renewable resources: existence, transitional dynamics, and empirical evidence

This paper studies an optimal endogenous growth model using physical capital, labor and two kinds of natural resources in the final goods sector and employing labor to accumulate knowledge. Based on results in calculus of variations, a direct proof of existence of optimal solution is provided. Analytical solutions for the planner case and the balanced growth paths are found for a specific CRRA utility and Cobb-Douglas production function. Transitional dynamics to the steady state from the theoretical model are used to derive three convergence equations of output intensity growth rate, exhaustible resource growth rate and renewable growth rate, which are tested based on data on production and energy consumption in 27 OECD countries.Optimal growth, existence of equilibrium, transitional dynamics, energy, renewable resource, non-renewable resource.

L’efficacité économique du mode d’allocation des ressources naturelles

In this paper, the decentralized economic allocation of a common property resource is fully characterized in a dynamic framework. Because of the externalities involved, this mode of allocation is shown to be inefficient. The extent and the causes of this inefficiency are discussed, with special emphasis on a kind of externality herein called the "appropriability". Finally, economic policies involving taxation, subsidy and user charge which purpose to bring about the social optimum are pointed out

Combination of formal logic and hedge algebra to estimate the degree of trust

Trust plays a more and more important role in many fields of computer sciences such as ambient intelligence, interaction human - machine, affective computing, etc. This paper firstly constructs a logical framework to represent the qualitative aspect of trust/distrust based on a logic of belief, a logic of time, and dynamic logic. Secondly, the paper constructs a hedge algebra and its extension with fuzzy logic to represent the quantitative aspect of trust/distrust and that of their cognitive factors. Then these two aspects are combined to estimate the degree of trust/distrust based on the degree of their cognitive factors.

Working Capital Management and Firm Profitability: Evidence from Industry Products and Services Enterprises Listed on the Vietnam Stock Market

The purpose of this study is to find out the effect of working capital management on company profitability. In light of this objective the study adopts quantitative approaches to test a series of research hypotheses. A sample of 86 industry products and services enterprises listed on the Vietnam stock market was used for a period from 2009 to 2019 with the total of 946 observations. The findings of the study showed that, there exists a highly significant negative relationship between average collection period and profitability indicating that a decrease in the number of days a firm receives payment from sales affects the profitability of the firm positively. This study will provide a general agenda to researchers, strategy makers, investors and professionals to guide future researches. Keywords: Working Capital, Profitability, Vietnam DOI: 10.7176/EJBM/12-27-12 Publication date:September 30th 202

THE UNCERTAINTY THAT SHAPES THE OPERATIONS OF HEALTH-FOCUSED NON-GOVERNMENT ORGANIZATIONS IN VIETNAM

Objective: This research project explores how uncertainty shapes NGOs operating in the health sector in relation to other institutions, and how NGOs strategize to maintain their image and survive under uncertain conditions, while working to improve population well-being. Methods: The research questions were answered through qualitative methods. Twenty semi-structured interviews were conducted, thirteen with the representatives of NGOs, and seven with high-ranking government officers at both central and provincial levels. In addition, documents (decisions, proposals, reports) were reviewed. Results: Numerous uncertainties internal and external to NGOs greatly influence their operations. As a result, they adjust their mandates, roles vis-à-vis government, accountability, and delivery methods to manage these uncertainties. Although relations with government were sometimes difficult, in general NGOs confirmed that they supported government priorities. Several lessons about operations, programming, policy making, and relationship building have been learned through this study, resulting in recommendations being made to the government, to NGOs in Vietnam (including their headquarters), and to donors, aiming to facilitate smooth NGO operations and benefit communities. Conclusion: NGOs have no standing in the local socio-political structure, a problem arising from the government’s restrictive control of the civil society sector. NGOs do their best to avoid notice, “hiding themselves” to avoid attention or scrutiny. As a result, government-NGO relations are highly problematic, and NGOs often struggle to implement sustainable programs at the community level. Further studies are required to identify effective modes of NGO operations under such circumstances, including work to identify methods for strengthening NGO capacity, increasing appropriate donor engagement, and facilitating the localization of foreign NGOs

ON NECESSARY CONDITIONS FOR EFFICIENCY IN DIRECTIONALLY DIFFERENTIABLE OPTIMIZATION PROBLEMS

This paper deals with multiobjective programming problems with in- equality, equality and set constraints involving Dini or Hadamard differentiable func- tions. A theorem of the alternative of Tucker type is established, and from which Kuhn-Tucker necessary conditions for local Pareto minima with positive Lagrange multipliers associated with all the components of objective functions are derived.Theorem of the alternative, Kuhn-Tucker necessary conditions, direc- tionally differentiable functions.