Risk-Based Capacitor Placement in Distribution Networks

In this paper, the problem of sizing and placement of constant and switching capacitors in electrical distribution systems is modelled considering the load uncertainty. This model is formu- lated as a multicriteria mathematical problem. The risk of voltage violation is calculated, and the stability index is modelled using fuzzy logic and fuzzy equations. The instability risk is introduced as the deviation of our fuzzy-based stability index with respect to the stability margin. The capacitor placement objectives in our paper include: (i) minimizing investment and installation costs as well as loss cost; (ii) reducing the risk of voltage violation; and (iii) reducing the instability risk. The proposed mathematical model is solved using a multi-objective version of a genetic algorithm. The model is implemented on a distribution network, and the results of the experiment are discussed. The impacts of constant and switching capacitors are assessed separately and concurrently. Moreo- ver, the impact of uncertainty on the multi-objectives is determined based on a sensitivity analysis. It is demonstrated that the more the uncertainty is, the higher the system cost, the voltage risk and the instability risk are

Explaining the aspects of entrepreneurial university in Technical and Vocational University Area 8

University in Technical and Vocational University Area 8 (Mazandaran, Golestan, and Semnan provinces). According to the review of the research studies in the past including Ataiee et al. (2017), the researchers in the present study concluded that applying the criteria of the entrepreneurial universities in the organizational and educational chart of universities will result in the development of the power of innovation and creativity of students and graduates to perform entrepreneurial activities; Mahdi (2015) believes that the establishment and effectiveness of the entrepreneurial university is not possible without the systematic development of entrepreneurship education and effective training of students, professors, managers and staff of the university system and strengthening the entrepreneurial characteristics of the university's human resources. Bahayani (2015) believes that the following four elements should be considered for entrepreneurship in universities: organizational structure and management style, education and research, government facilities for entrepreneurial activities, entrepreneurial culture. Also, Naderi et al. (2014) emphasizes the entrepreneurial  capabilities of students in terms of independence, internal control, motivation, success, risk-taking and creativity in different stages of higher education and by presenting a model with six different dimensions, they intend to take into account the dimensions and components of the entrepreneurial university within the technical and vocational university, which is the only university in charge of higher technical and vocational education in the country, and technical and vocational colleges, as the sub-units of this university, have a history of more than 40 years of educational activity and are among the first centers of higher education in the country. In fact, by determining the dimensions and components of the entrepreneurial university, it is possible to find out whether we have achieved our desired goals or not? Methods: This research is applied in terms of purpose and descriptive in terms of method. The statistical population in this study is comprised of 448 individuals selected from all heads, deputies, official managers or expert officials and department heads of the technical and vocational colleges and institutes in district 8 (in Mazandaran, Golestan, and Semnan provinces). 207 individuals were chosen through applying stratified random sampling and Cochran formula. To collect data, a researcher-made questionnaire with 95 items was used. The validity and reliability of the research tools were confirmed. To analyze the data, exploratory and confirmatory factor analysis tests were applied. Findings: The research findings have indicated that the entrepreneurial university in the technical and vocational university includes 6 aspects: educational and research aspects, structural and organizational aspects, human resources, social and cultural aspects, economic and financial aspects, information and communication technology, and 18 components: (educational and research), (structural, prespective, mission, strategy, management and leadership), (professors, staff, university students and graduates ), (social and cultural), (economic, financial, facilities,  equipment and research contracts) and ( infrastructure, offices, centres and companies). Conclusion: From the findings, it can be concluded that in addition to identifying the dimensions and components of the entrepreneurial university, the structural and organizational aspect with the load factor of 0.950 has the most influence and the social and cultural aspect with the load factor of 0.874 has the least influence.  ===================================================================================== COPYRIGHTS  ©2021 The author(s). This is an open access article distributed under the terms of the Creative Commons Attribution (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, as long as the original authors and source are cited. No permission is required from the authors or the publishers.  ====================================================================================

Study of water's physico-chemical characteristics in the southern Caspian Sea

This study was conducted to determine the physico-chemical characteristics of water during four season and 8 transects (Astara, Anzali, Sefidroud, Tonekabon, Nowhshar, Babolsar, Amirabad, Bandar Tourkman) in the Southern of Caspian Sea in 2009-2010. 480 samples were collected at different water layers and then physicochemical parameters were measured based on standard methods. Result of this study showed that surface water temperature was varied from 7.2 to 29.8◦C in winter and summer, respectively. Minimum fluctuation of water temperature was observed at 100 m depth (6.8-10.3◦C). Mean value of water transparency was obtained 4.91±0.24 m. This value increased from inshore to offshore. pH value was fluctuated from 7.15 to 8.83 unit with variance of 1.54. Maximum DO concentration was observed at surface layer (8.40±0.08 mg/l) with 137±18 saturation and minimum was at 100 m depth (6.46±0.18) with 86.1±2.8 saturation. The nitrite, nitrate and ammonium concentration were ranged 0.0-0.2, 0.0-4.6 and 0.05-7.12 µM, respectively. Maximum value of TN was observed at inshore and minimum at offshore (100m). Nitrite concentration decreased from inshore to offshore but increased from surface to the bottom (100 m). The inorganic phosphorous increased at surface water and also at the bottom. Trend of inorganic and TP was similar. Minimum of N/P ratio were observed at summer (5.48±0.38) and maximum value at winter (9.13±0.46). This value of N/P ratio showed that the growth of phytoplankton was limited by nitrogen. The dissolved silicate was decreased from spring (230.7±6.65 µg/l) to winter

Stock assessment of kutum (Rutilus frisii kutum) in the Iranian waters of Caspian Sea

This study was conducted to determine catch and fishing effort trends, length and age composition, growth and mortality parameters and estimate biomass and acceptable biological catch of Kutum in the Iranian coastal waters of Caspian Sea from 2013 to 2015. The catch of Kutum was 6112.8 and 5599.2 tons and CPUE were 181.1 and 183.5 kg/haul in 2013-2014 and 2014-2015, respectively. The mean (± SD) of fork length were observed 39.4±6.1 and 40.7±5.6 cm and for total weight were 805.1±378.0 and 891.5±384.6 gram in 2013-2014 and 2014-2015, respectively. The most predominated of length class was obtained 40-42 cm and frequency of immature individuals were observed 37.8 and 44.4 percent during two sampling period, respectively. The range of age was from 2 to 11 year and fish with 4 to 6 years comprised up to 84 percent. In length – weight relationship a, b and r2 were calculated 0.011, 3.02 and 0.96 respectively. K value, L_∞ and t0 were calculated 0.19 (/year), 61.3 cm and -0.99 respectively. Mortality parameters such as Z, M and F were calculated 0.82, 0.36 and 0.46 respectively and Exploitation rate were calculated 0.56. The biomass of kutum estimated 41000 tons and the acceptable biological catch calculated 8250 to 9750 tons. The biomass of Kutum decreased in recently years in spite of produce and release of huge fingerlings. This recruitment (produce and release fingerlings) must be continued for stability of stocks and fishing stress must be decrease by anyway

Study of physico-chemical Characteristics of water in the southern of Caspian Sea

This study was conducted to physico-chemical characteristics of water in the Iranian coastal of southern Caspian Sea during four seasons at 8 transects (Astra, Anzali, Sefidrud, Tonekabon, Nowshahr, Babolsar, Amirabad and Bandar Turkman) during 2009-2010. 480 samples were collected at different layers of water and then analyzed based on standard methods. Results showed that the mean of water temperature were 18.67±0.32 and 17.82±0.43 ◦C at the surface and euphotic layer, respectively. Minimum and maximum of water temperature were recorded in winter (6.40) and summertime (27.60). In addition, temperature gradient was ranged between 12 to 15 ◦C at 20 to 50 layers in 50 and 100m depths. Mean of salinity was 11.04±0.17 g/l at euphotic layer. Pearson correlation between temperature and salinity was positively significant. Therefore, maximum salinity was recorded in summer and minimum in winter. Mean of transparency (SD) in the present study was 4.35±0.21 m which compared to the pervious sampling period (2008) showed small decrease, but the mean of pH was observed 8.43±0.01 which was higher than the previous sampling period (2008). The mean of DO and DO% were observed 5.72±0.06 ml/l and 130±1 percent at euphotic layer during sampling period. The mean of DO% was recorded 104±5 at euphotic layer in 1996 (before introduction of Mnemeiopsis leidyi), but the study in the years 2004, 2008 and present (one decade after introduction of Mnemeiopsis leidyi) this value was registered higher than 120% at euphotic layer. This shows that trophic status of Caspian ecosystem shifted from oligotrophy (before introduction of Mnemeiopsis leidyi) to meso-eutrophy (after introduction of Mnemiopsis leidyi). Annual concentration of inorganic nitrogen (DIN= NH^4 +, NO^2-, NO^3-) has a fairly wide variation. Percentage of nitrogen components out of DIN were varied 9-98, 0.2-28.2 and 0.0-90.0 respectively. In this study, percentage of DIN was lower than 15% and organic nitrogen (DON) was higher than 80%. Overall, results showed that water temperature, salinity, transparency and DON were recorded lower than the previous study (2008), but DO, DO%, pH, NH^4+, NO^3- and DSi were higher than the previous sampling period. Inorganic phosphorous (DIP) and NO^2- have not changed substantially. N/P ratio of Caspian Sea has a narrow range which order of magnificent lower than other seas. The results of the present study showed that Caspian ecosystem was nitrogen limitation before introduction of Mnemiopsis leidyi, while it seems that after introduction of Mnemiopsis leidyi the system has been shifted to the phosphorous limitation

Survey of diversity, distribution, abundance and biomass of macrobenthic fauna in the southern Caspian Sea

Sediments samples were collected using Veen Grab Sampler (0.1 square meter) at 8 transects namely Astara, Anzali, Sefidroud, Tonekabon, Noshahr, Babolsar, Amirabad, Torkman in the southern of Caspian Sea. Five stations were selected at 5, 10, 20, 50 and 100 meter depths in each transect. Sediments were sampled triplicate at each station. Samples also were collected during four seasons (spring (May), summer (July), fall (November) and winter (January)) in 2009. Results of this study showed that species composition of Macrobenthos consisted of 32 species which belonged to 7 families of Polychaeta, Crustacea and Bivalvia at studied area. In addition, Oligochaeta identified in “Class”, Chironomidae considered in Insecta categories “Family” and Streblospio spp. (Polychaeta) was recognized in “Genus”. Gammaridae and Pseudocumidae of Crustacea with 12 and 10 species had the highest species diversity compared to other groups, respectively. Polychaeta was consisted 75.5 percent of total abundance of macrobenthos which the major abundance (equal 62.4% of total abundance) were belong to Streblospio spp. from Spionidae family, while its biomass was equals 5.11% of total macrobenthos. In contrast, Cerastoderma lamarcki species from Bivalvia Class with only 1.7% of total abundance of macrobenthos allocated 69 percent of total biomass. In the southern of Caspian Sea, average total abundance was significantly less at 4 western transects (Astara, Anzali, Sefidroud, Tonekabon) compared to 4 eastern transects (Noshahr, Babolsar, Amirabad, Torkman) (p<0.05). The highest average abundance of macrobenthos (10655±1246SE ind/m^2) was observed at transect of Torkman, and lowest value (4032 ± 686SE ind/m^2) was recorded at transect of Sefidroud (p< 0.05). Generally, minimum species diversity were obtained at 20 m depth in all transects and the maximum value was observed at 5 m depth in most of transects (p<0.05). In contrary, maximum average abundance of Macrobenthoses was at 20 m depth in transects of Anzali, Sefidroud, Tonekabon, Nowshahr and Amirabad compared to other depths. Macrobenthoses abundance average in 5 m depth (except Astara and Torkman) was less than other depths in 6 transect (p < 0.05). Total average abundance and biomass of macrobenthos was 5976±583SE ind/m^2 and 43.675 ± 11.402SE gr/ m^2, respectively. Maximum and minimum of abundance of macrobenthos were observed in summer (7714±778 ind/m^2) and winter (4071 ± 340 ind/m^2), respectively. Maximum and minimum of biomass of macrobenthos were obtained in fall (50.271±13.258SE gr/ m^2) and in summer (35.123 ± 8.903SE gr/ m^2), respectively (p< 0.05). Percent of total organic matter (TOM) were low in 5 and 10 m depths and increased toward offshore depths. TOM percent was 2.06±0.11SE at 10 m depth and increased to 4.62 ±0.17SE in 100 m depth. Percent of silt and clay (grains size less than 63 micron) had positive significantly correlation with percent of TOM (p<0.01).While they had negative significantly correlation with percent of sand (grains size between 63 and 1000 micron) (p<0.01). Percent of silt and clay like organic matter, had ascending trend toward to depth increased and varied from 44.4 ± 4.06SE percent in 5 m depth to 96.5 ± 0.59SE percent in 100 m depth. In contrast, percent of sand decreased toward depth and varied from 54.5 ± 4.13SE percent in 5 m depth to 2.8 ± 0.53SE percent in 100 m depth. Result of current study showed that total abundance of macrobenthoses had positive significantly correlation with TOM percent (p<0.01) and silt/clay percent (p<0.05). Abundance of Oligochaeta had positive significantly correlation (p< 0.01) with TOM and silt/clay percent. Two groups of Polychaeta, Gammaridae and Cerastoderma lamarcki had negative significantly correlation with TOM and silt/clay percent (p< 0.01), and every four aforementioned groups had positive significantly correlation with sand percent (p< 0.01). Overall, different correlation between abundance of various macrobenthos groups and TOM percent and type of grain size of sediment could be related to fluctuation of abundance of various macrobenthos groups at difference transects and depths. On the other hand, in study area were occurred simultaneously some phenomena such as increased abundance of Oligochaeta and Polychaeta, dominance of Streblospio Genuse (Polychaeta group), and decreases abundance of Bivalvia and appearance of Menemiopsis leidyi which need to study more and monitoring of this area

Evaluation of NPP1 as a novel biomarker of coronary artery disease: A pilot study in human beings

Purpose: Coronary artery calcification (CAC) is utilized as an important tool for global risk assessment of cardiovascular events in individuals with intermediate risk. Ecto phosphodiesterase/nucleotide phosphohydrolase-1(ENPP1) converts extracellular nucleotides into inorganic pyrophosphate and it is a key regulator of tissue calcification that adjusts calcification in tissues like vascular smooth muscle cells. The main purpose of this clinical study was to find out the correlation between ENPP1 serum concentration and CAC in human for the first time. Methods: In this study 83 patients (16 diabetic patients and 67 non-diabetic patients) with coronary artery disease who fulfilled inclusion and exclusion criteria, entered the study. For all patients a questionnaire consisting demographic data and traditional cardiovascular risk factors were completed. Computed tomography (CT)-Angiography was carried out to determine coronary artery calcium score and enzyme-linked immunosorbent assay (ELISA) method was used for measuring ENPP1 serum concentrations. Results: There was a reverse significant correlation between ENPP1 serum concentration and total CAC score and also CAC of right coronary artery (RCA) (P < 0.05) in non-diabetic patients. Conclusion: On the basis of our results, ENPP1 serum concentration may be a suitable biomarker for coronary artery disease at least in non-diabetic patients. However, more studies with higher sample size are necessary for its confirmation. © 2018 The Authors

The study abundance, distribution and diversity of zooplankton in the southern of Caspian Sea

This survey was carried out by R/V Guilan ship with a conical plankton net of 100 micron mesh by vertical hauls at different stations and depths of 5, 10, 20, 50 and 100m in 4 seasons of 2010. In this study, 16 species formed the zooplankton community including 4 species of Copepoda, 4 species of Rotatoria, 2 species of Protozoa and 4 species of Cladocera from Holoplanktons and 2 species of Balanus sp and Lamellibranchiata larvae from Meroplanktons. The annual results revealed that the mean abundance of zooplankton were 5477±5815 ind/m^3 and 5131±7908 ind/m^3 in spring and winter respectively which were more than other seasons but the maximum biomass (64/58±124/61mg/m^3 ) was in winter that was affected by Rotatoria. The maximum mean abundance and biomass of Copepoda were in summer that were 2830±2342 ind/m^3 and 22/52±21/78 mg/m^3 ,respectively and the abundance decreased gradually since autumn and reached the least in winter but increased since spring. The mean maximum abundance of Cladocera (115 ±142 ind/m^3) was in spring but it decreased gradually, so it reached to less than 3 ind/m^3 in summer. The Protozoa constituted the least community and biomass of zooplankton in southern area of Caspian Sea. The zooplankton community also was affected by Meroplanktons including Cirripedia and Lamellibranchiata Larvae in spring and the Rotatoria contributed highly in zooplankton community in winter with the mean abundance and biomass of 2604±5876 ind/m^3 and 50/71±115/33 mg/m^3 respectively.Other than Copepoda, other planktonic groups contributed lowly in zooplankton community. It was observed the reduction trend in abundance from surface depths to deeper depths in whole of the year. There were 75% of zooplankton community in stations with 5 to 20m depth and 25% of community in stations with 50 to 100m depth in spring, and also 74% in stations with 5 to 20m depth and 26% in stations with 50 to 100m depth in summer, 73% in stations with 5 to 20m depth and 27% in stations with 50 to 100m depth in autumn and 85% in stations with 5 to 20m depth and 15% in stations with 50 to 100m depth in winter. In analysis of different area of southern basin of Caspian sea the maximum abundance was observed in west in spring, summer and winter which were 7514±8115 ind/m^3, 3909±2609 ind/m^3 and 8129±11587 ind/m^3, respectively. There was 2283±2134 ind/m^3 in center area in autumn. The annual statistical analysis revealed that, there was significant difference in total zooplankton community between sampling stations, depths and layers in whole of the year

Study on physico-chemical characteristics of water in the southern of Caspian Sea

In this study, the characteristics of physico-chemical parameters of water done in coastal part of the southern Caspian Sea during 2010-2011 (four seasons) in 8 transects (Astara, Anzali, Sefidrour, Tonkabon, Noshahr, Babolsar, Amirabad and Torkman). For measurement of water quality parameters, 480 samples were collected in different water layers by using of APHA standards methods. According to modeling and statistical methods was used multivariate for evaluation of factor analysis (MFA) in general groups and discriminant analysis (MDA) for spatial and temporal with water quality parameters. The statistical procedure of MFA was used for data reduction and finally six factors selected with about 80.48 percent of total variances related to them. The statistical procedures of MDA were used for the role of spatial and temporal of water quality parameters in different water layer. The function one gave eight parameters (pH, salinity, EC, DO, NO^3-, water temperature, NH^4+ and N^-total) affording more than 80, 67, 80, 77 and 71 % correct assignations (return to the same transects) in spatial analysis. In all transects during four seasons, function one gave five parameters (water temperature, salinity, EC, NO^2- and NH^4+) to afford 100, 100, 100, 97 and 97 % correct assignations in temporal analysis. The results showed that, the average amounts in light penetration layers during four seasons were for EC(15.04±0.18ms/cm), pH(8.38±0.01unit), salinity (10.31±0.16g/l), DO(5.67±0.09ml/l) and water temperature (18.28 ±0.72°C). The average amount of nutrients for parameters such as organic and inorganic phosphorus, total phosphorus, NO^2-, NO^3-, NH^4+, N^-Total and SiO_2 were 0.50±0.02, 0.32±0.01, 0.82±0.02, 1.76±0.10, 0.10±0.01, 1.51±0.10, 46.82±1.80 and 8.60±0.29µM, respectively. The average amounts in dark layers during four seasons were for EC (15.46±0.38ms/cm), pH (8.34±0.03unit), salinity (10.70±0.35g/l), DO (4.55±0.13ml/l) and water temperature (9.62 ±0.16°C). The average amount of nutrients for parameters such as organic and inorganic phosphorus, total phosphorus, NO^2-, NO^3-, NH^4+, N^-Total and SiO_2 were 0.54 ±0.05, 0.33 ±0.02, 0.87±0.06, 1.92±0.21 , 0.08± 0.01, 1.55±0.25, 45.10±3.25 and 10.05±0.62 µM, respectively. The average amounts of light penetration in all transects during four seasons 4.49±0.38 meters. The maximum light penetrations during spring, summer, fall and winter seasons were 9, 8, 8.20 and 7 meters, respectively. The maximum water temperatures in light and dark layers were 32.36 and 11.50°C. Also, the maximum differences about thermocline temperature during summer and fall seasons were 19.6°C and 10°C, respectively in southern part of Caspian Sea. Data in spatial analysis were not significant (p>0.05), it means if add or removed any transect did not change occurred. But in temporal analysis were significant (p<0.01), and it means no way remove any seasons for a research work on Caspian Sea in southern part. In those transects with 100m depth. Water temperature is only highly effective parameter between other parameters. In function 1 between 3 functions in transects with 100m depth water temperature with 60% variance was the main role and effective between different seasons in depth part were very high