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We address the problem of serving plug-in hybrid electric vehicles (PHEVs) in a charging station using a local storage energy unit, with finite capacity. Our goal is to find a control policy minimizing the operational cost of the charging station. We assume that the price of the electrical power unit is determined by a Real Time Pricing scheme, in which, the price of the electrical power is continuously updated with respect to the state of the grid at each time instance. We first model the charging station as a continuous time Markov Decision Process with three control actions: the probability of blocking new arrivals, the rate of charging the battery and the proportion of cars being served by the battery. By using dynamic programming, we prove the existence of the optimal policy minimizing a discounted cost over an infinite time horizon. We also show that it is stationary and bang-bang, i.e. the admissible action set in the optimal policy assumes only the extreme values in the action set.

We consider a problem of scheduling electric power demands in a smart-grid framework. Our model consists of n energy requirements {Ai, li, ri}ni=1, needed to be scheduled in time interval [0,1]. Here Ai is the amount of energy, while li and n are respectively, the left and right constraints on the length of the time period, during which Ai has to be supplied without interruption. The triples are assumed to be i.i.d. random vectors, with A distributed according to some general distribution G, and pair (l, r) distributed uniformly in the region {0 ≤ li ≤ r ≤ 1}. Our goal is to find a scheduling policy minimizing the power peak - maximal power over [0,1] - and/or the operational convex cost of the system while satisfying all the demands. The problem becomes very complicated as the number n of demands increases. To address this issue, we consider an asymptotic approach, in which the average amount of energy in each demand is inversely proportional to n, thus keeping the total scheduled amount stable. In this paper we first introduce lower bounds for both types of costs and then introduce a scheduling algorithm, asymptotically optimal in the sense that its cost converges to a corresponding lower bound almost surely, as n increases to infinity. Moreover, the algorithm is on-line (each demand is scheduled at the time its parameters become known) and has fully linear running time.

We consider a problem of supplying electricity to a set of $\mathcal{N}$ customers in a smart-grid framework. Each customer requires a certain amount of electrical energy which has to be supplied during the time interval $[0,1]$. We assume that each demand has to be supplied without interruption, with possible duration between $\ell$ and $r$, which are given system parameters ($\ell\le r$). At each moment of time, the power of the grid is the sum of all the consumption rates for the demands being supplied at that moment. Our goal is to find an assignment that minimizes the {\it power peak} - maximal power over $[0,1]$ - while satisfying all the demands. To do this first we find the lower bound of optimal power peak. We show that the problem depends on whether or not the pair $\ell, r$ belongs to a "good" region $\mathcal{G}$. If it does - then an optimal assignment almost perfectly "fills" the rectangle $time \times power = [0,1] \times [0, A]$ with $A$ being the sum of all the energy demands - thus achieving an optimal power peak $A$. Conversely, if $\ell, r$ do not belong to $\mathcal{G}$, we identify the lower bound $\bar{A} >A$ on the optimal value of power peak and introduce a simple linear time algorithm that almost perfectly arranges all the demands in a rectangle $[0, A /\bar{A}] \times [0, \bar{A}]$ and show that it is asymptotically optimal.

Background: Finasteride partially blocks the conversion of testosterone to dihydrotestosterone through inhibition of 5α-reductase in hair follicles. Finasteride cream can penetrate into the dermis and the hair follicle due to its solubility. Therefore, it is expected to be used in the treatment of hirsutism with fewer systemic adverse side effects. This study was designed to determine the efficacy of finasteride cream 0.5% in the management of idiopathic hirsutism. Methods: Finasteride (0.5%) and placebo creams were administered to 35 women with facial hirsutism. Medication and placebo creams were each used on one side of the face in an area of excessive hair growth, which were not necessarily symmetrical. The side of the face for the finasteride and placebo creams was chosen randomly and blindly in 1cm2 areas on each side of the face. The hairs were counted and their thickness was also measured by micrometer, and their mean was calculated at the start of therapy and after 6 months. Statistical analysis was done in SPSS software using Paired and Student t-tests. P-values less than 0.05 were considered significant. Findings: The mean of hair numbers decreased on the placebo-applied side from 12.20 ± 6.15 to 10.50 ± 4.90 (P < 0.001), and on the finasteride-treated side from 11.37 ± 6.15 to 8.47 ± 4.62 (P < 0.001). Mean of hair thickness on the placebo side decreased from 2.92 ± 0.84 µm to 2.72 ± 0.79 µm (P < 0.001), and on the finasteride side from 3.17 ± 0.90 µm to 2.37 ± 0.79 µm (P < 0.001). Comparison of hair number and thickness showed no statistically significant changes in finasteride versus placebo treated sides. However, according to the patients' view points, hair growth rate was diminished and hair was thinner on the finasteride-treated side. Conclusion: Six months of topically applied finasteride (0.5%) does not affect the number and thickness of facial hirsutism significantly. Despite the lack of changes, on questioning, most patients in the finastride group perceived a decrease in hair growth over time.

Mobile IP is used to manage the mobility of the Internet mobile users, and to keep their connectivity while they move from place to place. The security of mobile IP considering can be divided into two aspects, first in registration process, second, when connected parties exchange data with each other. In this article, after a brief study on the existing approaches used for securing mobile IP connections and after pointing to their problems, a new method will be introduced. This method is based on using IPsec security mechanism in conjunction with MOBIKE protocol. It will be pointed out that by using this proposed approach, the security of mobile IP connections will be achieved with respect to both two mentioned aspects. And also it is shown that most of the problems of existing approaches are eliminated in this method.

IPsec security mechanism standard offers Internet key exchange protocol (IKEv2) for establishing and managing its secure sessions. In IKEv2 both two participants perform the same amount of calculations in all cases and this would cause some deficiencies, when it is used in different situations with different properties. For example in most of client-server connections it is more preferable for servers to do fewer operations in comparison with clients. In the other side in some connections, initiators are entities with less power of computing when comparing with responders. Mobile users are examples of such entities. In these connections, the initiators are the entities who need to perform fewer operations. To solve this problem, we propose two protocols with asymmetric schemes for distribution the calculations. In proposed protocols, one of the participants performs fewer computations, depending on the properties of connections. To achieve this asymmetric scheme, Schnorr signature scheme is used by the entity needs to perform fewer computations.

New version of Internet key exchange protocol (IKEv2) is introduced in this article. Despite of its several advantages, it suffers from some deficiencies when applying in client-server environments. The main problem is regarded to its inefficient method for resisting against DoS attacks. A new protocol is proposed in this article, in which besides keeping maximum fidelity to IKEv2 framework, new necessary features are added. More resistance against DoS attacks without forcing extra delays, and identity protection of initiators (clients) against active attackers are the advantage of using this protocol. Also asymmetric distribution of calculations scheme, introduced in this protocol, makes it unique, while comparing with other protocols.

There has been a big debate on the evolution of agricultural development (AD), the challenges and problems hindering AD in Iran since last decade. This study was implemented in the province of Esfahan and a number of 130 out of 212 agricultural experts from 13 different townships were selected as the target group. Totally 70 experts returned the completed questionnaires. The findings of the study revealed that most of the AD changes have been positive but in a very slow rate. Respondents unanimously claimed that the sustainability in agriculture and maintenance of agricultural lands are the most deteriorating issues during last ten years. With regard to AD problems, they stressed the lack of adequate fund allocated to the Ministry of Agriculture (MAJ) and lack of its power to control beneficiary dealers within the sector, unfair political influence, lack of international contacts and also untrustworthiness of agriculture for private investors as the most problematic obstacles for AD in Iran. They perceived that MAJ has not sufficiently addressed the problems so far, although, there are some promising movements. Experts believed that MAJ is not able to solve the majority of problems alone due to their extrinsic nature.

The purpose of this study was to analyze farmers’ experiences with and perceptions of agricultural extension courses and their instructors in Esfahan, Iran. This study is part of a larger project on the development of a competency profile of extension instructors. Many attempts have been made to develop competency profiles for professionals (Shim, 2006). A perennial problem is the extent to which differentiation is needed as a consequence of the characteristics of the target group (Mulder, Wesselink, & Bruijstens, 2005). This study, conducted in 17 different townships in the province of Esfahan, Iran, involved interviews with 27 farmers and a survey of 102 farmers who participated in course. Data were collected on the following factors: motives for course attendance, course appreciation, topics for future courses, and the competence of the agricultural extension instructors (AEIs). The relationships between farmers’ personal and farm characteristics and the factors were also examined. Based on the results of this study, a general competency profile is possible, but that variation is needed as to the age, gender, educational level, and learning motives of farmers. Target group stratification and internal differentiation in courses should be included in the competency profile.

This thesis is aimed at developing a competency profile for instructors in the agricultural extension service in theprovinceofEsfahaninIran. These instructors are part-time subject matter specialists who cooperate with the Ministry of Agriculture and teach short-term extension courses in different disciplines to farmers. Previous research revealed that the target group of the research generally experience many problems in their role of instructor during extension courses for farmers. The PhD project was conducted to develop a competency profile for this role in the next three to five years. In doing that, a comprehensive review of the literature was carried out, the competency models presented by McLagan (1982) were selected and adjusted to the Iranian extension system, and were tested for the role of instruction. To increase the reliability of the model, different respondents were involved: participating and non-participating farmers in extension courses, agricultural experts, agricultural managers, and instructors.The research carried out in the project is presented in this book, which contains three main parts and nine chapters. The first chapter is the general introduction, which provides the literature review, problem statement, research design, definition of concepts, study area and the outline of the thesis. Part one of the thesis presents four farmers' studies, part two encompasses two agricultural experts' studies and part three includes the key study of the research and the synthesis. In the synthesis chapter the implications of all previous chapters about the competency profile of the target group are aggregated and the model is triangulated.The findings of this research show that the evolution of agricultural development and extension has not been convincing during the last decade and that farmers were confronted with many unexpected changes and problems in their work. The Ministry of Agriculture (MAJ) has supported farmers to a limited extent, and much more support is needed in the future. However, the governmental extension services are assumed as being the most important information source for farmers. Farmers were generally pleased with the services of the extension organization and with their courses, as well as with the instructors, but they expect revisions in evaluation methods, the use of instructional technologies, and the duration of the courses and follow up strategies delivered by the instructors. The most important motives of farmers for participation in the courses were performance improvement and personal development.Respondents of the key study (chapter eight) gave high scores to all components (future forces, ethical issues, outputs, standards and competencies) of the competency profile of the instructors. It was concluded that instructors should perform additional roles apart from instruction. New general and common competencies were inserted into the final version of the competency profile of the instructors. Ultimately, this research revealed that designing a common competency profile for instructors is possible but the profile should be differentiated based on the stratification of the farmer population by variables such as gender, age, level of education, and motives for course participation. Further research is proposed both for the role of instructors and other human resource professionals in the field of agricultural extension inIran. Also, repeating this study at national and international level, also in different sectors, could enhance professional development in various occupations and thereby socio-economic development in these sectors, and could further elaborate the instrumental use of the model.

A project is carried out for instructors in the agricultural extension service in Esfahan. Part of the project is study, conducted to inform the process of competency profile development for the instructors. The study, reported in this contribution, focuses on views of experts about competencies needed by the instructors. The survey is based on the methodology for developing models of HRD, in which 257 key experts participated. A mix of methods was used for collecting data. The most important competencies found in this study are subject matter and business understanding, and presentation skill. The most essential outputs are presentation of instructional materials, feedback to learners and equipping learners with new competencies after the course. In this contribution, competencies and outputs are elaborated. Further research is needed regarding performance improvement as a result of the efforts of the instructors, and the views of other stakeholders on the development of the agri-clusters.

This study is part of a bigger project aimed at designing a competency profile for agricultural extension instructors (AEIs). The present study was designed to investigate farmers’ perceptions of the kinds of support that the Agricultural Extension Services (AES) organization in Iran has provided so far, and of the kinds of support that should be provided by AES in the future. 102 farmers, who had already attended AES extension courses, were selected from 17 townships in the province of Esfahan. The farmers completed a questionnaire during a personal interview. The two most-used information sources by farmers to get informed about AES programs were governmental extension agents and their own experiences. The farmers claimed that AES has already supported them to some extent in the past but has focused on animal husbandry and veterinary, agricultural inputs and enhancement of the fertility and size of the farms. For the future, they expressed the need for greater support from AES, most importantly in relation to making an agricultural career more satisfactory for them and to reducing the risk, labor and severity of farming. The farmers were especially positive about the short-term extension courses offered in different disciplines over the last ten years and they regarded these programs as useful.

Since 1954, various informal training programs for farmers have been implemented to support them in several aspects of their life and careers in Iran. This study aimed at assessing the results of informal technical and vocational training programs (ITVTP) in the field of agriculture on the employment status of farmers in the province of Isfahan in Iran. A number of 330 farmers (equally divided over an experimental and a control group) were selected from 19 townships of the province mentioned to be interviewed. Structured questionnaires were completed during the interviews. The results show the education level of the majority of farmers in both groups is low; most of them are married, smallholder and more than 40 years of age. Statistical analysis showed there is a positive relationship between ITVTP (as an independent variable) and different aspects of the lives and careers of farmers (as dependent variables), such as job stability, job satisfaction and motivation, income generation, investments in the agriculture sector, information and competence, the employment of families, and production capacity of farmers. The findings underline the importance and supporting role of ITVTP for many factors relating farming.

Let G be a molecular graph. The Wiener indices of G are defined as the sum of the shortest paths between vertices of G . In this paper, the exact formulae for the Wiener indices of ( O p ( Q 2.0 ( T ) ) ) − T U ( 3 , 0 ) are given.

Background: Finasteride partially blocks the conversion of testosterone to dihydrotestosterone through inhibition of 5 α- reductase in hair follicles. Finasteride cream can penetrate to dermis to arrive at hair follicle due to its solubility. Therefore, it is expected to be used in treatment of hirsutism with less systemic adverse effects. This study was designed to determine the efficacy of finasteride cream 0.5% in management of idiopathic hirsutism. Methods: Finasteride (0.5%) and placebo creams were administered to 35 women with hirsutism on the face. Medication and placebo creams, each one was used on one side of the face in an area of excessive hair growth, which were not necessarily symmetrical. The side for the finasteride and placebo creams were chosen randomizly and blindly in 1cm2 areas on each side of the face. Hair numbers were counted and the thickness of all hairs was also measured by micrometer and their mean was calculated, at the start of therapy and after 6 months. Statistical analysis was done in SPSS software using Paired and Student t-tests. P-values less than 0.05 were considered significant. Results: The mean of hair numbers decreased at placebo-applied side from 12.20 ± 6.15 to 10.50 ± 4.90 (P