The Beta-Gompertz Distribution

In this paper, we introduce a new four-parameter generalized version of the Gompertz model which is called Beta-Gompertz (BG) distribution. It includes some well-known lifetime distributions such as beta-exponential and generalized Gompertz distributions as special sub-models. This new distribution is quite flexible and can be used effectively in modeling survival data and reliability problems. It can have a decreasing, increasing, and bathtub-shaped failure rate function depending on its parameters. Some mathematical properties of the new distribution, such as closed-form expressions for the density, cumulative distribution, hazard rate function, the $k$th order moment, moment generating function, Shannon entropy, and the quantile measure are provided. We discuss maximum likelihood estimation of the BG parameters from one observed sample and derive the observed Fisher's information matrix. A simulation study is performed in order to investigate this proposed estimator for parameters. At the end, in order to show the BG distribution flexibility, an application using a real data set is presented.Comment: http://www.emis.de/journals/RCE/ingles/v37_1.htm

Quantitative and qualitative assessment of sport places, spaces and facilities from safety and bioenvironmental point of view

The purpose of current research is quantitative and qualitative assessment of athletic places, spaces and sports facilities in Dushanbe, Tajikistan from safety and bioenvironmental point of view; and presenting the results about shortages and problems of preservation and maintenance of these premises and equipment. For this purpose, data from three researcher-made questionnaires contains 100 variables (43 variables for evaluation of quantity and quality of places, spaces, and sports equipment in Dushanbe city in Tajikistan; 21 variables about health and safety conditions of buildings and equipment, and dedicated 36 variables to bioenvironmental conditions of the above mentioned places and equipment) were analyzed; and the study population consisted of the 19 sport place and spaces in terms of location, space, sports facilities of Ministry of youth, Sports and tourism of the Republic of Tajikistan. Due to the limited number of available subjects, all the statistical population has been considered as study sample. Required information was collected within 10 months period of study, then, analyzed using descriptive statistics. Face and content validity of the measurement instrument has been approved by faculties and sports scientists. Our findings show that: 1. In terms of quantity, sport spaces of Dushanbe was reported as 26.8 % weak, and 30% moderate, and also in terms of quality of places, spaces and sports equipment 34.8 % good, 26.1 % average. 2. In terms of safety and health condition, places, spaces and sports equipment mentioned above was about 39.1 % moderate and 21.7% good. 3. In terms of bioenvironmental conditions; sport places, spaces, and equipment was amounted to 69.6 % of good condition as well. In summary, we can considered equipment shortages and financial constraint as the main problem of sports development in Dushanbe, Tajikistan; which caused redouble inattention to health and the safety of these places

Biotechnology, important applications and ethics

Background and aims: Recent advances in Genetic Engineering and Biotechnology provided more facilities for human to manipulate and alter any form of life. This technology has many useful applications in medicine, pharmacology, agriculture and industry. The most Important applications of biotechnology are: improving of inherited traits (plants and animals), production of new drugs in live bioreactors, creating models and patterns for the study of human diseases and organ transplantation. Like other technologies, it has own ethical considerations and Subsequently, it has come up with different ideas. So, it can be studied from different aspects of ethics. Methods: This study is a review project. All data that presented in this study were collected from different sources and electronic databases. Results: Although some scientists opposite with some of biotechnology applications using scientific reasons, some are basically opposite with biotechnology in any form and application. Important protestations come from two groups: some religious and some secular. Religious group resist to alteration of life with this concept that any alteration in life using genetic engineering, insult to God decision, humanity and life. Secular also like religious have this belief or faith and assume genetic engineering and biotechnology as insult to humanity and life merit. Conclusion: The analysis of the arguments of these two opponents based on the West ethical principles and the principles of Islamic ethics shows that using biotechnology with its ethical and scientific considerations toward life, not only insult to God decision, humanity and merit but also unusing of it in their concepts can reverse or violate humanity and merit

Remarks on Stable Formulas in Intuitionistic Logic

ONNILLI-formulas were introduced in [2] and were shown to be the set of formulas that are preserved under monotonic images of descriptive or Kripke frames. As a result, ONNILLI is a syntactically defined set of formulas that axiomatize all stable logics. In this paper, among other things, by proving the uniform interpolation property for ONNILLI we show that ONNILLI is exactly the set of formulas that are preserved in monotonic bijections of descriptive or (finite) Kripke models. This resolves an open problem in [2]

Recurrent Poisson Factorization for Temporal Recommendation

Poisson factorization is a probabilistic model of users and items for recommendation systems, where the so-called implicit consumer data is modeled by a factorized Poisson distribution. There are many variants of Poisson factorization methods who show state-of-the-art performance on real-world recommendation tasks. However, most of them do not explicitly take into account the temporal behavior and the recurrent activities of users which is essential to recommend the right item to the right user at the right time. In this paper, we introduce Recurrent Poisson Factorization (RPF) framework that generalizes the classical PF methods by utilizing a Poisson process for modeling the implicit feedback. RPF treats time as a natural constituent of the model and brings to the table a rich family of time-sensitive factorization models. To elaborate, we instantiate several variants of RPF who are capable of handling dynamic user preferences and item specification (DRPF), modeling the social-aspect of product adoption (SRPF), and capturing the consumption heterogeneity among users and items (HRPF). We also develop a variational algorithm for approximate posterior inference that scales up to massive data sets. Furthermore, we demonstrate RPF's superior performance over many state-of-the-art methods on synthetic dataset, and large scale real-world datasets on music streaming logs, and user-item interactions in M-Commerce platforms.Comment: Submitted to KDD 2017 | Halifax, Nova Scotia - Canada - sigkdd, Codes are available at https://github.com/AHosseini/RP

An empirical study to determine the critical success factors of export industry

Exporting goods and services play an important role on economy of developing countries. There are many countries in the world whose economy is solely based on exporting raw materials such as oil and gas. Many believe that countries cannot develop their economy as long as they rely on exporting one single group of raw materials. Therefore, there is a need to help other sectors of industries build good infrastructure for exporting diversified products. In this paper, we perform an empirical analysis to determine the critical success factors on exporting different goods. The results are analyzed using some statistical non-parametric methods and some useful guidelines are also suggested

The Role of Water Resources Management in Reducing the Production Costs of Agricultural Products

In order to achieve the goals of sustainable agricultural and rural development, agricultural education is an issue that should be in base considered and researched according to the importance of the issue and its related challenges must be realistically analyzed, Since water is one of the effective factors in the agricultural sector that plays a vital role in the production of agricultural products. There are several factors for low water productivity in the country, one of which can be considered non-optimal and unplanned use of water. It is clear that by increasing the level of awareness of farmers about the type of management of agricultural water resources it is possible to reduce current expenses and then to achieve high productivity and increasing income from crops and orchards. Therefore, in this study, the optimal management of water and reduction of production costs in the agricultural sector in Zabrkhan county of Neishabour city has been studied. The research method in this article was a descriptive- analytical method and the data was collected by two methods of library and field methods. The results show that the production cost per hectare of all crops in lands under water resources management is less than unmanaged lands. This rate varied between 3.4 to 16.8 percent. If we associate this reduction in production cost with product efficiency and use the cost per kilogram of production as a criterion, the reduction will be 165.2% for irrigated wheat, 150% for irrigated barley, 106.8% fodder corn and 54.4% for garden products. Therefore, according to the research results, the research hypothesis is confirmed

Choosing an optimum sand control method

AbstractFormation sand control is always one of the main concerns of production engineers. There are some different methods to prevent sand production. Choosing a method for preventing formation sand production depends on different reservoir parameters and politic and economic conditions. Sometimes, economic and politic conditions are more effective to choose an optimum than reservoir parameters. Often, simultaneous investigation of politic and economic conditions with reservoir parameters has different results with what is expected. So, choosing the best sand control method is the result of thorough study. Global oil price, duration of sand control project and costs of necessary equipment for each method as economic and politic conditions and well productivity index as reservoir parameter are the main parameters studied in this paper