323 research outputs found
FDD Algorithm for an AHU Reverse-Return System
A fault detection and diagnosis (FDD) algorithm was developed for an AHU reverse-return system for air cooling. These FDD rules were generated using simulation in three steps. Cause-effect rules were established by connecting the faults and their related effects. The FDD rules were developed for the following faults: old valve, fouled return pipe, fault in the outlet air temperature sensor, fault in the temperature sensor for the inlet temperature, bad position of the sensor for pressure difference. The effects of the involved faults were observed on four system performances. The results showed that increase in both the cooling coil rate and the pump rate appear due to faults in sensors. The inaccurate measurement of the pressure difference and the fault in the control valve do not affect the AHU outlet air temperatures. Increase in both the outlet air temperature and the pump power consumption appears due to the fouled return pipes
Preparing Students for the Advanced Manufacturing Environment Through Robotics, Mechatronics, and Automation Training
Automation is one of the key areas for modern manufacturing systems. It requires coordination of different machines to support manufacturing operations in a company. Recent studies show that there is a gap in the STEM workforce preparation in regards to highly automated production environments. Industrial robots have become an essential part of these semi-automated and automated manufacturing systems. Their control and programming requires adequate education and training in robotics theory and applications. Various engineering technology departments offer different courses related to the application of robotics. These courses are a great way to inspire students to learn about science, math, engineering, and technology while providing them with workforce skills. However, some challenges are present in the delivery of such courses. One of these challenges includes the enrollment of students who come from different engineering departments and backgrounds. Such a multidisciplinary group of students can pose a challenge for the instructor to successfully develop the courses and match the content to different learning styles and math levels. To overcome that challenge, and to spark students\u27 interest, the certified education robot training can greatly support the teaching of basic and advanced topics in robotics, kinematics, dynamics, control, modeling, design, CAD/CAM, vision, manufacturing systems, simulation, automation, and mechatronics. This paper will explain how effective this course can be in unifying different engineering disciplines when using problem solving related to various important manufacturing automaton problems. These courses are focused on educational innovations related to the development of student competency in the use of equipment and tools common to the discipline, and associated curriculum development at three public institutions, in three different departments of mechanical engineering technology. Through these courses students make connections between the theory and real industrial applications. This aspect is especially important for tactile or kinesthetic learners who learn through experiencing and doing things. They apply real mathematical models and understand physical implications through labs on industrial grade robotic equipment and mobile robots
Norwegian National Program for Lifetime Commissioning and Energy Efficient Operation of Buildings
The project āLife-Time Commissioning for Energy Efficient Operation of Buildingsā is actually a network of industrial companies, private and public entities, and R&D organizations. The overall objective of the project is to contribute to the implementation of life-long commissioning of building HVAC systems, so that this becomes a standardized way of building, operating and maintaining the HVAC systems in Norway. The project is organized as an industry research program with minimum duration of five years. Project members pay an annual membership fee. The main goal for the project is to develop, verify, document and implement suitable tools for functional control of energy and indoor environment in buildings under continuous operation during the entire operational life of the building. This will improve energy efficiency and ensure a rational use of energy and a sound indoor environment. All achievements concerning energy improvement will also contribute to the decrease of CO2 emissions
The Possibility of Contamination of Deep Frozen Bull Semen During Long Periods of Storage in Containers with Liquid Nitrogen
Preservation of bull sperm by deep freeze is a technological process that allows you to store semen in theory for an unlimited period of time, national and international transport, without significant loss of quality and safety of semen. According to the literature, some microorganisms successfully survive the low temperatures during storage of semen in liquid nitrogen (-196 Ā° C), in deep-frozen semen, seeds, and in liquid nitrogen and ice sediment in the storage container for deep-frozen bull semen. The aim of this study was to do microbiological analysis of samples semen frozen bull and liquid nitrogen in containers for bull semen storage. 414 samples of frozen bull semen, and 53 samples of liquid nitrogen ice sediment were examined. From the deeply frozen semen were isolated Candida albicans, Citrobacter freundii and Pseudomonas stutzeri. Microorganisms isolated from the storage container of frozen semen are mostly members of the family Enterobacteriacae, and Citrobacter freundii was isolated from the largest number of samples. Considering the findings of microorganisms in the semen, and liquid nitrogen, there is the possibility of connection of contamination of the semen with microorganisms of the liquid nitrogen, and reversely, as would be the goal of our future investigations
Organotypic tissue culture investigation of homocysteine thiolactone cardiotoxic effect
Homocysteine thiolactone was demonstrated to inhibit the growth of 10ā12-day-old chicken embryo cardiac tissue explants at 7 Ć 10ā9 ā1 Ć 10ā3 M concentrations in a dose-dependent manner. The maximal cardiotoxic effect of homocysteine thiolactone was detected at 1 Ć 10ā3 M, which corresponds to severe hyperhomocysteinemia. The results of experiments on culturing of cardiac tissue explants in the medium containing homocysteine thiolactone (1 Ć 10ā3 M) and ouabain at concentrations regulating the signal-transducing (1 Ć 10ā10 M) and pumping (1 Ć 10ā8 M) functions of Na+,K+ -ATPase indicate that the cardiotoxic effect of homocysteine thiolactone is supposed to result from inhibition of the Na+,K+ -ATPase pumping function
Iron concentrations in atherosclerotic plaque and serum in patients with carotid atherosclerosis
The aim of this study was to investigate the iron concentrations in serum and carotid plaque in patients with different morphology of carotid atherosclerotic plaque and compared with other metal ions. Carotid endarterectomy due to the significant atherosclerotic stenosis was performed in 91 patients. Control group consisted of 27 patients, without carotid atherosclerosis. Atherosclerotic plaques were divided into four morphological groups, according to ultrasonic and intraoperative characteristics. Iron, copper and zinc concentration in plaque, carotid artery and serum were measured by spectrophotometry. Serum iron concentrations were higher in patients with hemorrhagic plaques in comparison to the control group (4.7 Ī¼mol/l Ā± 1.2 vs. 2.1 Ī¼mol/l Ā± 0.8, p < 0.05). Iron concentrations were higher in patients with hemorrhagic plaques in comparison to fibrolipid plaques (72.1 Ā± 14.3 Ī¼g/g vs. 39.3 Ā± 22.9 Ī¼g/g; p < 0.05). Negative significant correlation was found for zinc in serum and plaque iron concentration in patients (p < 0.05). We also demonstrated positive significant correlation for copper and iron in serum (p < 0.05). The data obtained in the current study are consistent with the hypothesis that high iron levels may contribute to atherosclerosis and its complications as factors in a multifactorial disease
Implementation of triticale in nutrition of non-ruminant animals
Cognition of chemical composition and nutritive values of triticale grain as well as the effect of its application in non-ruminant animal nutrition were pointed out in this paper. There is a high level of proteins in the grain of triticale (2 to 3% more than wheat and 4% more than rye), with very beneficial amino acid composition, and is the reason for its usage in domestic animals nutrition. Nowadays, people are of the opinion that triticale is one of potential plant species with the brightest perspective in the production of food for domestic animals. Considering the increased production of triticale, some detail researching of its nutritional value is necessary due to the required evaluation of the role and significance in domestic animal nutrition based on triticale. Due to intensive plant breeding programs, there are new varieties of triticale in the market, distinctive by the higher yield and wide range of desired traits. As a result of this, triticale is becoming very attractive and is occupying larger portions of arable land. These review will show if there are some advantages of triticale compared to other cereals and how large the frame of these advantages is, as well as how it will affect the further spreading of triticale on arable land.Key words: Triticale, chemical composition, nutritive capacity, nutrition
Co-overexpression of bcl-2 and c-myc in uterine cervix carcinomas and premalignant lesions
To establish the role of co-overexpression of bcl-2 and c-myc protooncogenes in uterine cervix carcinogenesis, we examined 138 tissue samples of low grade cervical squamous intraepithelial lesions (SIL), high grade SIL, portio vaginalis uteri (PVU) carcinoma in situ and PVU invasive carcinoma, stage IA-IIA (study group) and 36 samples without SIL or malignancy (control group). The expression of bcl-2 and c-myc was detected immunohistochemically using a monoclonal antibody. Fisher's exact test (P<0.05) was used to assess statistical significance. Overexpression of bcl-2 was found to increase in direct relation to the grade of the cervical lesions. High sensitivity was of great diagnostic significance for the detection of these types of changes in the uterine cervix. On the basis of high predictive values it can be said that in patients with bcl-2 overexpression there is a great possibility that they have premalignant or malignant changes in the uterine cervix. Co-overexpression of bcl-2 and c-myc oncogenes was found only in patients with PVU invasive carcinoma (6/26-23.0%). Statistically significant difference was not found in the frequency of co-overexpression in patients with PVU invasive carcinoma in relation to the control group (Fisher's test; P=0.064). The method's sensitivity of determining these oncogenes with the aim of detecting PVU invasive carcinoma was 23%, while specificity was 72.2%. On the basis of high predictive values (100%), speaking in statistical terms, it can be concluded that all patients with co-overexpression of bcl-2 and c-myc oncogenes will have PVU invasive carcinoma. We confirmed in our research that co-overexpression of bcl-2 and c-myc oncogenes was increased only in PVU invasive carcinoma. However, a more extensive series of samples and additional tests are required to establish the prognostic significance of bcl-2 and c-myc co-overexpression in cervical carcinogenesis
Norwegian National Program for Lifetime Commissioning and Energy Efficient Operation of Buildings
The project āLife-Time Commissioning for Energy Efficient Operation of Buildingsā is actually a network of industrial companies, private and public entities, and R&D organizations. The overall objective of the project is to contribute to the implementation of life-long commissioning of building HVAC systems, so that this becomes a standardized way of building, operating and maintaining the HVAC systems in Norway. The project is organized as an industry research program with minimum duration of five years. Project members pay an annual membership fee. The main goal for the project is to develop, verify, document and implement suitable tools for functional control of energy and indoor environment in buildings under continuous operation during the entire operational life of the building. This will improve energy efficiency and ensure a rational use of energy and a sound indoor environment. All achievements concerning energy improvement will also contribute to the decrease of CO2 emissions
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