Reliability Evaluation of Electric Power Generation Systems with Solar Power

Conventional power generators are fueled by natural gas, steam, or water flow. These generators can respond to fluctuating load by varying the fuel input that is done by a valve control. Renewable power generators such as wind or solar, however, are not controllable since their fuel sources are intermittent in nature. This creates difficulties for designing generation systems having renewable sources. Therefore, a mechanism is needed to predict their power outputs and evaluate the generation system reliability. This information is used to calculate the reliability indices such as Loss of Load Expectation (LOLE), frequency of capacity deficiency, and Expected Unserved Energy (EUE). These indices help to estimate to what extent renewable power plants with intermittent sources can substitute for other power generations in the system while maintaining the same reliability standards. This study is used in generation planning of power systems with intermittent sources. The primary objective of this thesis is to study reliability evaluation of generation systems including Photovoltaic (PV) and Concentrated Solar Power (CSP) plants. Unit models of PV and CSP are developed first, and then generation system model is constructed to evaluate the reliability of generation systems. In addition to reliability indices calculations, a methodology is developed to evaluate the capacity credit of PV and CSP plants. This is accomplished by calculating the Effective Load Carrying Capability (ELCC) of these plants. ELCC is the extra load that can be served after addition of the solar power plant to the conventional system. The capacity credit information, in addition to its use in generation system planning, can also be used for cost comparison between conventional power plants and solar power plants. The methodology developed in this thesis is applied to IEEE Reliability Test System (IEEE-RTS) to study the system reliability for different penetration levels of solar power and evaluate their capacity credits. It is found that generation system reliability drops as solar power penetration level increases. Also, solar plant capacity credit drops as its penetration level increases in generation system

Topological electronic structure of twin boundaries and twinning superlattices in the SnTe material class

The topological electronic structure of a single twin boundary and coherent twinning superlattices (TSLs) based on the SnTe class of material is calculated and discussed within a supercell implementation. The superlattices consist of two twin planes (TPs) in the supercell arranged in such a way that each of the boundaries forms a mirror plane for the entire structure. Two types of TP boundary, cationic and anionic, can exist, and so three types of supercells can be constructed. We study the topological phases of each twinning configuration using the tight-binding approximation and calculating the topological invariants. We show that they differ by topological properties. We find that all-cationic TSLs are topologically distinct from the anionic case due to the opposite sign of the Berry curvature around the $\mathrm{ \Gamma}$ point of the TSLs Brillouin Zone. Our findings are consistent with a complementary analysis of (111)-oriented slabs with a single twin boundary in the presence of the Zeeman field. They are also consistent with the number of spin-polarized Dirac-like edge states of both superlattices and slabs. We conclude that each type of TP forms the 2D mirror-plane-protected topological crystalline insulator

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یکی از مباحث اصلی در بازار سرمایه، توضیح نوسانات قیمت در این بازار با استفاده از الگوهای بنیادی است. در دو دهه اخیر برای افزایش توانایی توضیحدهندگی این الگوها، تعدیلاتی در آنها صورت گرفته است. از جمله این تعدیلات، ورود جزء حباب به الگوهای بنیادی برای افزایش توانایی آنها در تشریح نوسانات قیمت است. در این مقاله با استفاده از تعاریف و روابط ریاضی، حباب قیمت سهام معرفی شده، سپس در چارچوب نظریههای رفتاری علت پیدایش آن تحلیل میشود. حباب به صورت یک متغیر مشاهده نشده در قالب فرم فضای حالت با استفاده از فیلتر کالمن از قیمت جاری استخراج شده و سپس میزان تأثیرپذیری حباب از رفتارهای جمعی، مدگرایی و شرایط روانی حاکم بر بازار بررسی میشود. بر اساس نتیجه بدست آمده از این پژوهش حباب قیمت در بورس اوراق بهادار تهران طی دوره 1376-1387 تحت تأثیر رفتارهای جمعی، مدگرایی و شرایط روانی حاکم بر بازار قرار دارد

Pattern of Alcohol Consumption among Men Consumers in Kerman, Iran, in 2014

Background: Alcohol consumption is a potential risk factor with acute and chronic health consequences and social impacts, which is more prominent among men. There is no precise statistics on the scope of alcohol consumption in Iran; however, there is some evidences showing an increasing trend, particularly among young generation. In order to evaluate the scope of this issue in Kerman, a large city in the south-east of Iran, this exploratory study was designed to approach a group of people having an experience of alcohol use.Methods: Samples were recruited to the study using a snowball sampling. 200 eligible subjects were questioned about the type of alcohol consumed, frequency of use, and other factors associated with alcohol consumption. In order to maximize the validity of responses, data were collected through self-administered questionnaires.Findings: The main alcoholic drinks consumed by individuals were the homemade distillates (46%), wine (22%), beer (14%), distilled spirits (11%), and medical alcohol (7%), respectively. The majority of individuals participating in the study (73%) used mostly homemade drinks; moreover, 63%, 26%, 9%, and 2% of subjects took monthly or less, two to four times a month, two to three times a week, and at least four times a week, respectively. Only 2% of the subjects were heavy consumers of alcoholic beverages.Conclusion: Due to the lack of control over homemade alcoholic beverages, its high levels can be a huge potential risk. Furthermore, it seems that both factors of access and price to be very effective in the amount of alcoholics taken by individuals. Therefore, further studies in this area will help to reduce the harm caused by alcohol consumption

Industry Based Style Investing and Herding Behaviour in Industry Level and Momentum Strategy Among Retail Investors

Abstract In this research, the application of "industry based style investing" and the momentum strategy among retail investors have been studied. In style investing, selection process takes place in two steps. First, target style and then one of the members of target style are chosen. In this research, target style is industry. In industry based style invesing, the choice of investment is not based on the information of a particular firm, but with the attention of industry level information. A sample of 22 industries was selected through a systematic elimination from the listed firms in Tehran Stock Exchange between 2008 and 2014. The results showed that the industry is used as a "style" by retail investors. However, the use of the momentum strategy among retail investors has not been observed and is seen against the reverse strategy. It seems that in the industry level, negative news is more effective and herd behavior for selling is significant. High activity on sell side may be due to the pessimism of retail  investor

Performance Evaluation of Intelligent Adaptive Traffic Control Systems: A Case Study

ABSTRACT Mashhad, the second largest city in Iran, like many other big cities, is faced with increasing traffic congestion owing to rapidly increasing population and annual pilgrimage. In recent years, Mashhad traffic and transportation authorities have been challenged with how to manage the increasing congestion with limited budgets for major roadway construction projects. Mashhad has recognized the need to improve the existing system capacity to get the most out of their current transportation system infrastructures. Since most of the delay times occur at signalized intersections, using an intelligent control system with proper capabilities to overcome the growing traffic requirements is recommended. Following comprehensive studies carried out with the aim of developing the Mashhad traffic control center, the SCATS adaptive traffic control system was introduced as the selected intelligent control system for integrating signalized intersections. The first intersection was equipped with this system in 2005. This paper describes the results of a field evaluation in which fixed actuated-coordinated signal timings are compared with those dynamically computed by SCATS. The effects of this system on optimizing fuel consumption as well as reducing air pollutants are fully discussed. It is found that SCATS consistently reduced travel times and the average delay per stopped or approaching vehicle. The positive impact of adaptive traffic control systems on fuel consumption and air pollution are also highlighted

Formulation of Menthol-Loaded Nanostructured Lipid Carriers to Enhance Its Antimicrobial Activity for Food Preservation

Purpose: Due to the antimicrobial property, menthol have significant potential for food preservation and foodstuff shelf life improvement. Nevertheless, menthol instability, insolubility, and rapid crystallization in aqueous media make it unsuitable for used in food products. This work was aimed to prepare menthol-loaded nanostructured lipid carriers (NLCs) to enhance its antimicrobial activity. Methods: Morphology, particle size and size distribution, encapsulation efficiency percent (EE%), and physical stability of the optimized formulation, prepared by hot melt homogenization method, were characterized by scanning electron microscopy, particle size analyzing, gas chromatography, and X-ray diffraction (XRD) methods. Minimum inhibitory concentration and minimum bactericidal concentration of menthol-loaded NLCs were evaluated and compared with conventional menthol emulsion against various Gram-positive (Staphylococcus aureus, Bacillus cereus) and Gram-negative bacteria (Escherichia coli), as well as one fungus (Candida albicans). Results: Menthol-loaded NLCs were spherically shaped nanosized (115.6 nm) particles with narrow size distribution (PDI = 0.2), suitable menthol EE% (98.73%), and appropriate physical stability after 90 days of storage period. XRD results indicated that menthol was in the amorphous form in the nanoparticles matrix. Antibacterial assay results revealed that the menthol-loaded NLCs exhibited significantly higher in vitro antimicrobial property than conventional menthol emulsion. The results also indicated that menthol-loaded NLCs had better effect on fungi than bacteria, and furthermore, antibacterial efficiency on Gram-positive bacteria was higher than Gram-negative bacteria. Conclusion: In conclusion, NLCs could be a promising carrier for improvement of antimicrobial activity and preservation efficacy of essential oils in foodstuffs

An Immunohistochemical and Polarizing Microscopic Study of the Tumor Microenvironment in Varying Grades of Oral Squamous Cell Carcinoma

Background Invasion of epithelial cells into the connective tissue brings about massive morphological and architectural changes in the underlying stroma. Myofibroblasts reorganize the stroma to facilitate the movement of tumor cells leading to metastasis. The aim of this study was to determine the number and pattern of distribution of myofibroblasts and the qualitative and quantitative change that they cause in the collagen present in the stroma in various grades of oral squamous cell carcinoma (OSCC). Methods The study was divided into two groups with group I (test group, 65 cases) consisting of 29 cases of well-differentiated squamous cell carcinoma, 25 moderately differentiated SCC, and 11 poorly differentiated SCC, and group II (control group) consisting of 11 cases of normal mucosa. Sections from each sample were stained with anti–α-smooth muscle actin (α-SMA) antibodies, hematoxylin and eosin, and Picrosirius red. Several additional sections from each grade of OSCC were stained with Masson’s trichrome to observe the changes in collagen. For the statistical analysis, Fisher’s exact test, Tukey’s post hoc honest significant difference test, ANOVA, and the chi-square test were used, and p < .05 was considered statistically significant. Results As the tumor stage progressed, an increase in the intensity α-SMA expression was seen, and the network pattern dominated in more dedifferentiated carcinomas. The collagen fibers became thin, loosely packed, and haphazardly aligned with progressing cancer. Additionally, the mean area fraction decreased, and the fibers attained a greenish yellow hue and a weak birefringence when observed using polarizing light microscopy. Conclusions Myofibroblasts bring about numerous changes in collagen. As cancer progresses, there isincrease in pathological collagen,which enhances the movement of cells within the stroma

Elucidation of Apigenin Derivatives from Ethyl Acetate Fraction of Stachys byzantina with Potent Antioxidant and Anti-Staphylococcus aureus Properties

The Stachys genus is a medicinal plant, with 34 different species, from Lamiaceae family that grows in Irano-Anatolian plateau. There are 12 species of Stachys native to Iran. Some species of Stachys have been used in traditional medicine of Iran, Turkey, Italy, Greece, China, and Japan for the treatment of various diseases like inflammation, common cold, and etc. Some researchers have noted many biological effects, such as cytotoxic, antioxidant, immunomodulator, anti-inflammatory and anti-bacterial effects for the members of this genus. There are a few evidences on phytochemical constituents of S. byzanthinaThe aim of this study was phytochemical investigation of various extracts of this plant to obtain the most efficient fractions and compound(s) to study the antimicrobial effects of this plant. Separation and isolation of compounds was performed by various methods of chromatography. The structure of each compound was identified by spectroscopic methods.Antimicrobial studies were performed on different fractions of S. byzantina by microdilution method and to determine the Minimum Inhibitory Concentration (MIC), agar well diffusion was done.Ethyl acetate fraction has the highest total phenol contents (1082.05 mg GAE/g fraction) and antioxidant capacity (IC50= 1.23 mg/ml). Also, ethyl acetate fraction, the most potential fraction of S. byzanthina, was demonstrated the largest inhibition zone (17.5 ± 0.7 mm) with 5 mg/ml in MIC against Staphylococcus auresus.Apigenin and its derivatives were isolated from this fraction and according to literature; they can be responsible for antibacterial activity of this fraction of S. byzanthina