573 research outputs found

    Wideband Directional Coupler for Millimeter Wave Application based on Substrate Integrated Waveguide

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    Recently, Substrate Integrated Waveguide (SIW) techniques have been noticed for millimeter wave devices in microwave applications. In this paper, we are developing a wide band directional 3 dB coupler with a phase of 90̊ phase delay in the range of 30-40 GHz based on periodic vias and multi hole structure. For achieving this wide bandwidth multi-section coupler is designed based on the theoretical modeling and the simulation result is compared with HFSS and CST with  two different  numerical  methods show good performance with low insertion and return loss, broad operational bandwidth and high isolation. A fractional bandwidth is about 28.5 %

    Effect of Operating Conditions of the Extraction Process on the Physical Properties of Lubricating Oil

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    Lubricating base oil is commonly extracted from lube-oil cut, a petroleum cut, with the use of an aromatic solvent. Aromatic content of the final product is an important criterion specifying the product quality. The aromatic removal process to produce the lubricating oil should be carried out in a Liquid-Liquid extraction column. In a typical solvent extraction process, solvent to feed ratio, solvent and feed temperatures, agitation rate, and settling time could directly affect the yield of extraction. In the current study, the effect of agitation rate and settling time on the yield of extraction was studied. It was found that a settling time of 2hrs and an agitation rate of 430 RPM to be the optimum parameters of the extraction process

    Developing Entrepreneurial Mindset in Industrial Engineering Classes: A Case Study

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    Instilling entrepreneurial mindset among engineering students is one of the challenges in engineering education. This paper presents the efforts to improve a core undergraduate industrial engineering course, Designing Value in Supply Chain, to infuse entrepreneurial thinking among students using an internally funded grant by Kern Entrepreneurial Engineering Network (KEEN). For this purpose, three new course modules are designed and their effectiveness on student learning is evaluated. This course is ideal for establishing entrepreneurially minded learning (EML) as a systematic approach is required for managing the chain of supply, especially since the impacts of the decisions are not isolated and will be spread out through the entire chain. In addition, creative multidisciplinary knowledge is required to address most of the supply chain challenges. The proposed modules are expected to promote students’ creative thinking, curiosity, collaboration and communication skills, and enable them to identify the opportunities where they can apply their technical skills to create value in the community based on customers’ expectations. These factors are key pillars of EML as proposed by KEEN. In the first course module, students propose a new product to be released to the market (idea generation). They complete this module as the product moves toward the end user in the supply chain following the concepts they learn during the term. This module enables the students to observe the domino impact of the decisions they make in the initial stages of supply chain and enhances structured learning experience by linking different concepts. In the second module, in order to expose the students to real life applications of the course content, wireless consumption data provided by students is used to practice different demand forecasting methods. Students also need to provide some economic analysis to choose the best solution alternative regarding their forecasted values. This module makes the learning process more meaningful as the learners observe a real life application of the subject. In the third module, students practice energy management in order to minimize energy waste as one of the most important types of waste in lean production systems. In this module, they are expected to determine several sources of energy waste on campus and propose action plans, and estimate the economic impact of their solution. As a result of this project, students learn how to create value and communicate an engineering solution in terms of economic benefits. Students provide a report for each module which is graded based on designed rubrics. All these modules are performed in teams which in turn improves students’ team work and collaboration skills. This paper elaborates the details of each module and learning outcomes, and presents the student evaluation results, and at the end discusses the lessons learned

    Effect of troxerutin on serum glucose level and lactate dehydrogenase activity after exhaustive swimming in male rats

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    زمینه و هدف: ورزش وامانده ساز منجر به آسیب عضلانی و کاهش منابع انرژی نظیر گلوکز می‌شود. هدف مطالعه حاضر بررسی اثر مکمل تروگزروتین بر سطح سرمی گلوکز و فعالیت لاکتات دهیدروژناز متعاقب شنا وامانده ساز در موش‌های صحرایی نر بود. روش بررسی: در این مطالعه تجربی، 32 سر موش صحرایی نر نژاد ویستار به صورت تصادفی به 4 گروه کنترل، ورزش + 75 میلی گرم بر کیلوگرم، ورزش+ 150 میلی گرم بر کیلوگرم و ورزش + 300 میلی گرم بر کیلوگرم تیمار تروگزروتین تقسیم شدند. کلیه حیوان‌ها به مدت 30 روز تمرین شنا (5 بار در هفته) انجام دادند. تروگروتین به صورت خوراکی روزانه به مدت 30 روز تجویز شد. در روز سی‌ام ورزش شنا وامانده ساز انجام و سطح سرمی گلوکز و فعالیت لاکتات دهیدروژناز اندازه گیری شد. یافته ها: نتایج نشان داد که مکمل تروگزروتین به طور معنی‌داری سطح سرمی گلوکز را در مقایسه با گروه کنترل افزایش می‌دهد (001/0>P) و همچنین فعالیت لاکتات دهیدروژناز در گروه ورزش + تروگزروتین (300) در مقایسه با گروه‌های کنترل و ورزش + تروگزروتین )150 میلی گرم بر کیلوگرم( کاهش یافت (05/0>P). نتیجه گیری: مطالعه حاضر نشان داد که تروگزروتین می‌تواند تأثیر قابل توجهی در کاهش آسیب عضلانی ناشی از ورزش شنا وامانده ساز داشته باشد

    THE SURVEYING OF THE POLARITY BY MOOD ADJUNCTS IN PERSIAN LANGUAGE BASED ON FUNCTIONAL GRAMMAR APPROACH

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    Polarity determines whether the message is positive or negative. This key element of every context can be expressed through mood adjuncts. The present study aimed at surviving the polarity of Persian mood adjuncts based on functional grammar approach. Both positive and negative discourses were presented and discussed. To achieve the purpose of the study, however, some negative mood adjuncts such as "hargez"(never), "be zahmat"(scarcely), "be nodrat"(rarely), and some positive mood adjuncts including "hamishe"(always), "aqlab" (often), "mamulan" (usually) and "barxi auqat" (sometimes) were discussed. Finally it was found that to carry a severe negative message in contexts using the negative polarity mood adjuncts in Persian language ٫"negative" markers are require

    Dvogodišnje serološko istraživanje virusa goveđe virusne dijareje, goveđeg alfa-herpesvirusa 1 i virusa goveđe parainfluence tipa 3 na farmama mliječnih krava u Qazvinu, sjeverozapadni Iran

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    Infections with bovine viral diarrhea virus (BVDV), bovine alphaherpesvirus 1 (BoHV-1), and bovine parainfluenza virus type 3 (BPIV-3) cause diseases in cattle with serious economic consequences worldwide. The objective of the present study was to determine of herd-level and animal-level BVDV, BoHV-1, and BPIV-3 seroprevalence, and evaluate some of the associated risk factors on farms in Qazvin province, Northwestern Iran. A total of 1036 cattle in 16 herds were randomly selected, and their serum samples were tested to detect antibodies to these viruses in a cross-sectional study over 2 years. The results showed the seroprevalence of BVDV, BoHV-1, and BPIV-3 was 100%, 56.3%, and 100% at herd-level and 55.1%, 5.1%, and 95.2% at animal-level, respectively. Statistical analysis revealed that the farm was a strong risk factor for all the studied viruses, while the year was determined as a risk factor for only BVDV (P<0.001). The seroprevalence of BVDV and BPIV-3 was significantly (P<0.01) affected by season. The proportion of seropositive cows increased with age for BVDV and BoHV-1 (P<0.001). Concurrent infection was the highest in mixed infections with BVDV and BPIV-3 (53.2%), and there was a positive correlation between BVDV and BoHV-1 seropositivity (R2= 0.106, P<0.001). The present study shows that infections of BVDV and BPIV-3 are common in cattle in Northwestern Iran and which implies the need to implement control programs to reduce the risk of the spread of these viruses.Infekcije virusom goveđe virusne dijareje (BVDV), goveđeg alfa-herpesvirusa 1(BoHV-1) i virusa goveđe parainfluenze tipa 3 (BPIV-3) uzrokuju pobol u goveda širom svijeta, sa znatnim ekonomskim posljedicama. Cilj ovog istraživanja bio je odrediti seroprevalenciju BVDV-a, BoHV-1 i BPIV-3, na razini stada i na razini životinje, te procijeniti rizične čimbenike povezane s tim virusima na farmama u pokrajini Qazvin u sjeverozapadnom Iranu. U presječnom istraživanju, koje je trajalo više od dvije godine, nasumično je odabrano ukupno 1036 goveda iz 16 stada čiji su uzorci seruma testirani kako bi se pronašla antitijela na tri navedena virusa. Rezultati su pokazali da je seroprevalencija BVDV-a 100 %, BoHV-1 56,3 %, a BPIV-3 100 % na razini stada, dok je na razini životinje seroprevalencija BVDV-a bila 55,1 %, BoHV-1 5,1 %, a BPIV-3 95,2 %. Statistička je analiza pokazala da je farma znatan rizični čimbenik za sve istraživane viruse, dok se kombinacija godine i sezone pokazala rizičnim faktorom samo za BVDV (P < 0,001). Na seroprevalenciju BVDV-a i BPIV-3 znakovito je utjecala sezona (P < 0,01). Omjer seropozitivnih krava za BVDV i BoHV-1 znakovito je rastao s dobi (P < 0,001). Najčešća je koinfekcija bila virusima BVDV i BPIV-3 (53,2 %), a ustanovljena je i pozitivna korelacija između seropozitivnosti BVDV-a i BoHV-1 (R2 = 0,106, P < 0,001). Ovo je istraživanje pokazalo da su infekcije BVDV-om i BPIV-3 česte u goveda u sjeverozapadnom Iranu što upućuje na potrebu uvođenja programa nadzora kako bi se smanjio rizik od širenja ovih virusa
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