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Journal of Energy and Power Engineering 2013年第5期7卷 1001-1008页

作者： Farid Berrezzek wafa Bourbia Bachir Bensaker Departement Genie Electrique Universite Med Cherif Messadia Souk Ahras 41000 Algerie Departement d'Electrotechnique Universite Badji Mokhtar Annaba Annaba 2300 Algerie Laboratoire d'Electromecanique Universite Badji Mokhtar Annaba Annaba 2300 Algerie

This paper deals with a nonlinear control strategy of induction motor that combines an input-output linearization control technique and a nonlinear observer design. It is well known that induction motors are the most widely used motors in electrical appliances, industrial control and automation. However, it is also known that induction motor control is a complex task that is due to its nonlinear characteristics. Two main features of the proposed approach are worth to be mentioned. Firstly, a nonlinear control is carried out using a nonlinear feedback linearization technique involving non available state variable measurements of the induction motor system. Secondly, a nonlinear observer is designed to estimate these pertinent but unmeasurable state variables of the machine. The circle-criterion approach is performed to compute the observer gain matrices as a solution of LMI （linear matrix inequalities） that ensure the stability conditions, in the sense of Lyapunov, of the estimated state error dynamics of the designed observer. Simulation results are presented to validate the effectiveness of the proposed approach.

关键词： Induction motor nonlinear control input-output linearization nonlinear observer circle criterion Lyapunov stability.

基于认知诊断模型框架评价阿富汗学生的数学能力 ——Ghor省的个案研究

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基于认知诊断模型框架评价阿富汗学生的数学能力 ——Ghor省的个...

作者： Mohammad Nasim wafa 东北师范大学

学位级别：硕士

Cognitive diagnosis models（CDMs）has gained a growing interest in educational or psychological *** of considering an overall ability,a detailed latent attribute profile is considered to obtain a finer-grained evaluation and *** the popularity of CDMs,rare researches were conducted in *** open up the analysis and mind,CDMs are employed in this article as a very first ***,the main goal of this study is to investigate on why it gets more difficult to learn Mathematics for Afghans students,and to evaluate and determine the strengths and weaknesses of the Afghanistan students in attributes and *** research aims at assessing the mathematics skills of 8 grade students in *** response data is from the questionnaires of Trends in International Mathematics and Science Study（TIMSS）*** commonly used CDMs were employed to fit the response data,including the deterministic,inputs,noisy,“and”gate（DINA）model and the deterministic,inputs,noisy,“or”gate（DINO）*** the assistance of CDMs,we could obtain not only the item parameters,but also the skill profile for each *** show that the examinees do best in Number domain while do worst at Data and *** in terms of model selection,DINA model fitted the data better than DINO model.

关键词： CDMs DINA DINO Q-Matrix TIMSS 2011

非政府组织在发展部门的作用：开伯尔—普赫图赫瓦合并区的案例研究

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非政府组织在发展部门的作用：开伯尔—普赫图赫瓦合并区的案例研...

作者： wafa Wazir 华北电力大学(北京)

学位级别：硕士

在发展中国家,存在着大量的发展问题。所有发展问题都与教育制度不良、侵犯基本人权、生活水平低下和剥夺基本需求有关。此外,一些组织正在不断努力改进发展指标。这些组织被称为非政府组织。该研究旨在解释非政府组织(NGO)在开伯尔-普... 详细信息

在发展中国家,存在着大量的发展问题。所有发展问题都与教育制度不良、侵犯基本人权、生活水平低下和剥夺基本需求有关。此外,一些组织正在不断努力改进发展指标。这些组织被称为非政府组织。该研究旨在解释非政府组织(NGO)在开伯尔-普赫图赫瓦合并区的作用。为实现研究目标,采用了定性研究方法。通过NVIVO软件进行了数据分析。这些研究结果突出了非政府组织的作用,并表明好战性、边境犯罪监管、文化规范和基本权利是影响非政府组织在部落地区作用的主要因素。研究得出结论,非政府组织在改善合并地区的政治、社会和经济指标方面发挥了重要作用。总的来说,一个非政府组织在开伯尔-普赫图赫瓦合并区发挥着积极作用。

关键词：关战斗非政府组织(NGO) 边境犯罪条例(FCR) 文化规范发展合并区开伯尔普赫通赫瓦

A Spatio-Temporal Odyssey Around the Concepts of Sustainable Development and Corporate Social Responsibility： Boundaries to Be Determined？

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Journal of Modern Accounting and Auditing 2011年第10期7卷 1158-1168页

作者： Azzedine Tounes wafa Chakroun Fafani Gribaa Groupe ESC Chambery Savoie France Sousse University Tunisia Montpellier 1 University France

The aim of this research is to analyze the emergence of the concepts of sustainable development （SD） and corporate social responsibility （CSR） in companies in time and space. A spatio-temporal reading will indicate the most important socio-political and environmental events that have emerged with these two concepts. In order to complete the odyssey, a spatio-temporal analysis has retraced the epistemological evolution of these latter, whilst at the same time remarking the appropriation that has been made by the different institutional and organizational actors. The historical and epistemological reviews tell us that these two concepts, which came into existence almost 80 years, have indefinite outlines; one can be substituted for the other. However, thanks to this odyssey, we have reduced the boundaries even further between sustainable development and social responsibility and shown their theoretic and historical association. The perspective adopted shows that the concept of corporate social responsibility is closely connected to that of sustainable development. This connection means that researchers in management science are faced with more new problem issues reaching further than the simple lack of conceptual consensuses.

关键词： corporate social responsibility eco-development spatio-temporal analysis sustainable development

Emotion and Cognition: The Case of Military Personals

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World Journal of Neuroscience 2017年第1期7卷 1-18页

作者： Abdelmajid Naceur wafa Ferchichi Rahme Boualleg Education Cognition Tice and Didactic (ECOTIDI) Higher Institute of Education (ISEFC) Tunis Tunisia Education Cognition Tice and Didactic (ECOTIDI) Tunis Tunisia

Tunisian veterans experienced uncommon circumstances that put their lives in permanent threat. In this context, it is crucial to understand the adaptive strategy they tend to use. Distress takes place when military veterans use ineffective coping styles within a taxing and high demanding context. The aim of the current study was to estimate the link between coping styles, the psychological well-being and work related stress. A second goal is to extend the analyses for clinical diagnosis and providing a specific interpretation of the military’s behavior. We investigated these issues in a qualitative study. Findings are discussed in the context of a theoretical framework of transactional approach. This was a survey with a random sample of military officers stratified by rank (n = 26). Coping strategy scale (CSS), perceived stress (PSS) and psychological well-being (PWBM) were administrated to veterans from different ranks (high ranks and low ranks). Additionally, Chi square frequencies were constructed between the perceived stress scales, coping strategies and psychological well-being. Results were consistent and showed a best fit between perceived stress and ranks of officers (X2 = 0.026, p p < 0.05). Our results reveal that only two major coping strategies are predominantly used: problem resolution and avoidance. This further clarifies that military personals are incapable to maintain emotional balance and a satisfied image of themselves, complete absence of happiness and balance.

关键词： Emotion Stress Well-Being Cognition Coping-Military Personals

Crystal Structure and Physicochemical Properties of 2-Diisopropylammonium Ethylammonium Sulfate Dihydrate

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Crystal Structure Theory and Applications 2012年第3期1卷 40-45页

作者： wafa Amamou Taha Guerfel Taher Mhiri Laboratoire de Chimie du Solide Université de Monastir Faculté des Sciences de Monastir Monastir Tunisie Laboratoire de l’Etat Solide Université de Sfax Faculté des Sciences de Sfax Sfax Tunisie

A new organic sulfate (C8H22N2)SO42H2O denoted DPAES is obtained by interaction of H2SO4 with the organic molecule 2-[Diisopropylamino] ethylamine. We describe its crystallographic and structural features. DPAES is triclinic, Pī, with the lattice parameters a = 6.8841(2)?, b = 8.4966(2)?, c = 12.0804(3)?, = 81.824(1)o, = 88.007(1)o, = 78.649(1)o, V = 685.72(3)?3, and Z = 2. Its atomic arrangement is described as inorganic chains of SO42- units and water molecules, these chains are interconnected by organic groups so as to build layers parallel to the (001) planes. The IR data of DPAES are reported and discussed according to the theoretical group analysis and by comparison with IR results of similar compounds. The coupled TG-DTA thermal study shows the departure of two water molecule, con- firming the hydrated character of this compound.

关键词： Chemical Preparation Crystal Structure Thermal Behavior Organic Sulfate Infrared and Raman Spectroscopy NMR Spectroscopy

Numerical Solutions for Quadratic Integro-Differential Equations of Fractional Orders

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Open Journal of Applied Sciences 2017年第4期7卷 157-170页

作者： Fatheah Alhendi wafa Shammakh Hind Al-Badrani Department of Mathematics King Abdulaziz University Jeddah Saudi Arabia Taibah University Madinah Saudi Arabia

In this article, variational iteration method (VIM) and homotopy perturbation method (HPM) solve the nonlinear initial value problems of first-order fractional quadratic integro-differential equations (FQIDEs). We use the Caputo sense in this article to describe the fractional derivatives. The solutions of the problems are derived by infinite convergent series, and the results show that both methods are most convenient and effective.

关键词： Fractional Quadratic Integro-Differential Equations Variational Iteration Method Homotopy Perturbation Method

Downhill Zagreb Topological Indices and <i>M<SUB>dn</SUB></i>-Polynomial of Some Chemical Structures Applied for the Treatment of COVID-19 Patients

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Open Journal of Applied Sciences 2021年第4期10卷 395-413页

作者： Bashair Al-Ahmadi Anwar Saleh wafa Al-Shammakh Department of Mathematics Faculty of Science University of Jeddah Jeddah Saudi Arabia

A graphical index is a numeric value corresponding to a graph which is structurally invariant and in molecular graph theory these invariants are known as topological indices. In the field of Chemical and Medical Sciences, the topological indices are used to study the chemical, biological, medical and pharmaceutical features of drugs. With reference to the previous deadly diseases, the COVID-19 pandemic has considered to be the biggest life threatening issue that modern medicines have ever tackled. COVID-19 is immedicable and even the existing treatments are only helping the certain group of sufferers. Scientists have tested available antiviral agents and got a favorable impact on recovering from pandemic. Some of these antiviral agents are remdesivir, chloroquine, hydroxychloroquine, theaflavin and dexamethasone. Keeping in view of the importance of topological indices in the study of pharmaceutical and chemical drugs, in this paper, we calculate the Mdn-Polynomial, some downhill Zagreb topological indices and some downhill Zagreb polynomials of some of the anti viral agents remdesivir, chloroquine, hydroxychloroquine, theaflavin and dexamethasone. The results thus obtained may be useful for the finding new medicine and vaccine for the treatment of COVID-19.

关键词： COVID-19 Remdesivir Chloroquine Hydroxychloroquine Theaflavin Dexamethasone Mdn-Polynomial Downhill Zagreb Polynomial

Laboratory biosafety measures of SARS-CoV-2 at containment level 2 with particular reference to its more infective variants

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Biosafety and Health 2022年第1期4卷 11-14页

作者： wafa Naeem Habiba Zeb Muhammad Ibrahim Rashid Department of Molecular Biology&Genetics Institute of Basic Medical SciencesKhyber Medical UniversityPeshawar 25000Pakistan

The novel betacoronavirus(Severe Acute Respiratory Syndrome Coronavirus 2,SARS‐CoV‐2)is a pathogen that causes deadly respiratory disease named coronavirus disease 2019(COVID‐19).The incidence of this disease has increased in the last few months affecting 257,832,881 people in 221 countries and 51,68,069 deaths worldwide according to Worldometer at 04:03 GMT on November 22,***,the emergence of this disease creates a challenge for health care providers in handling this pathogen and reducing its risk of *** developing countries,this virus is treated in biosafety level 2 laboratories,where a high concentration of pathogen can easily affect the laboratory staff and cause the spread of this *** on the epidemiology and characteristics of the SARS‐CoV‐2 virus already discussed in recent studies,we will provide biosafety guidelines and suggestions for safe handling and transportation of the SARS‐CoV‐2 virus in dealing with the current pandemic situation with a focus on increased infectivity of emerging new variants.

关键词： SARS‐CoV‐2 Biosafety guidelines COVID‐19 PPE Laboratory acquired infections

Planning for the Solid Waste Management of Central Park in New Capital Development of Afghanistan

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Journal of Environmental Protection 2016年第6期7卷 805-815页

作者： Sifatullah Mukhtar wafaurehman wafa Haroon Halimzai Ajmal Khan Shams Infrastructure Planning and Designing Division Dehsabz-Barikab City Development Authority Kabul Afghanistan Faculty of Environmental Sciences University of Kabul Kabul Afghanistan Afghanistan Agriculture Input Project Ministry of Agriculture Irrigation and Livestock Kabul Afghanistan Operation and Maintenance Division Dehsabz-Barikab City Development Authority Kabul Afghanistan

Kabul New City is a new capital development and a modern city development of Afghanistan covering total area of 740 km2. In 2009 Afghan cabinet approved developing New Capital to fulfill the requirement of growing population. For sustainable development, it has been planned to have a green belt and central park about 1298 hectares within the city. It is having positive impact on human health along with the economic, social and environmental benefits. Hence, for sustaining the urban parks, their proper maintenance is a foremost problem. The solid waste management is duly considered in planning stage of development, otherwise, it would encounter major challenges during operation and maintenance of Park. The projected waste generation in KNC park area is required to be assessed, therefore, surveys of Bagh-e-Babur in existing Kabul are carried out for the visitors’ projection and solid waste generation. The highest visitors and waste were estimated in declining order of summer, spring, fall, and winter. Kabul New City Central Park results speculate that the total visitors’ projection is going to be 6,745,313 per year generating about 337 metric tons wastes/year (0.05 kg/visitor/day). 10 Vehicles of capacity 8 m3 are required to collect waste from central park towards the Transfer Station while 4 vehicles of 23 m3 are required for collection of waste from TS to Landfill. Moreover, 700 containers of 240 liters are required in the park. Furthermore, different sites were indicated in map for composting area where after the development it would be considered.

关键词： Kabul New City Central Park Solid Waste Management Operation and Maintenance