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Thermal Characterization of Concrete and Cement Mortar from Construction Sites and Industrial Production Units in the City of Ouagadougou with a View to Standardization in Energy Certification

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Engineering（科研） 2023年第6期15卷 396-415页

作者： Saïdou Bamogo Fati Zoma Etienne Malbila David Y. k. Toguyeni Laboratory of Physics and Chemistry of Environment (LPCE) University JKZ-UFR Ouagadougou Burkina Faso Laboratory of Thermal and Renewable Energy (LETRE) University JKZ-UFR Ouagadougou Burkina Faso Polytechnic School of Ouagadougou (EPO) Ouaga Burkina Faso

The present study allowed to carry out a thermal characterization of concrete and cement mortar. Thermal tests were carried out with the k.2 Pro device, on concrete and mortar samples tak.n from twenty-six (26) construction sites of office buildings and two (2) industrial production units in the city of Ouagadougou. The tests were carried out on rectangular specimens after four week. (4) of conservation on the site of construction or production of materials. This study seek. to determine the thermal properties of the materials, in particular the thermal conductivity, the thermal diffusivity and the thermal capacity of the samples, in the real conditions of execution of the buildings and environment. The thermal conductivity varies from 1.413 to 1.965 W/m·k. 0.940 - 1.658 W/m·k.and 0.703 - 1.149 W/m·k.respectively for concrete, cinder block.mortar and plaster mortar. Regarding the other properties, especially the capacity and thermal diffusivity, the values vary respectively, from 1070.59 - 1974.67 k./k.·k.and (3.74 - 6.70) × 10-7 m2/s for concrete, from 1123.69 - 1586.81 k./k.·k.and (3.38 - 5.65) × 10-7 m2/s for plaster mortar and 1202.51 - 1736.01 k./k.·k.and (3.82 - 7.36) × 10-7 m2/s for the mortar of building block.. The conductivity, capacity and thermal diffusivity of industrial mortar vary from 1.019 - 1.229 W/m·k. 792.18 - 1862.58 J/k.·k.and (2.75 - 6.80) × 10-7 m2/s, respectively. Only the correlations made between the thermal properties and the density of the samples of the plaster mortar, give good relations namely R2 = 0.9308 for the thermal conductivity, R2 = 0.7823 for the thermal capacity and R2 = 0.9272 for the thermal diffusivity. This study contributes to the establishment of a thermal regulation in Burk.na Faso for the adoption of the West African Economic and Monetary Union (WAEMU) Directive 05 on energy efficiency in buildings.

关键词： Concrete Mortar Thermal Conductivity Thermal Capacity Thermal Diffusivity

Frequency Features Based Fuzzy System for Rotating Machinery Vibration Analysis Using Smartphones Low-Cost MEMS Sensors

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Journal of Sensor Technology 2016年第3期6卷 56-74页

作者： Abdelrahman Ali k.mel El-Serafi Salwa A. k. Mostafa Naser El-Sheimy Electrical Engineering Department Faculty of Engineering Port-Said University Port-Said Egypt Geomatics Engineering Department Schulich School of Engineering University of Calgary Calgary Canada

Smart devices have become an important entity for many applications in daily life activities. These devices have witnessed a rapid improvement in its technology to fulfill the increasingly diverse usage demands. In the meanwhile, rotating machinery vibration analysis based on low-cost sensors has gained a considerable attraction over the last few years. For a long time, the vibration analysis of machines has been accepted as an effective solution to detect and prevent failures in complex systems to avoid the sudden malfunction. The objective of this work.is to use MEMS accelerometer measurements to monitor the different level of vibration of a machine. This work.presents a new technique for rotating machinery vibration analysis. It uses Fast Fourier Transformation as a feature extraction algorithm and Fuzzy Logic System (FLS) as the classifier algorithm. A smartphone accelerometer is used to collect the data from the vibrating machine. The performance of the proposed technique is tested using data from different vibration resources at a different speed of operations. The results are discussed to illustrate the various vibration levels.

关键词： Vibration Analysis Low-Cost Sensors Fuzzy Logic Frequency Analysis

k.netic Monte Carlo Simulation of Metallic Nanoislands Grown by Physical Vapor Deposition

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Communications in Computational Physics 2011年第1期9卷 49-67页

作者： Abuhanif k.Bhuiyan S.k.Dew M.Stepanova Department of Electrical and Computer Engineering University of AlbertaEdmontonAlbertaCanada T6G 2V4 National Institute for Nanotechnology NRC EdmontonAlbertaCanada T6G 2M9.

We report k.netic Monte-k.rlo(k.C)simulation of self-assembled synthesis of nanocrystals by physical vapor deposition(PVD),which is one of most flexible,efficient,and clean techniques to fabricate *** particular,self-assembled arrays of nanocrystals can be synthesized by *** size,shape and density of self-assembled nanocrystals are highly sensitive to the process conditions such as duration of deposition,temperature,substrate material,*** efficiently synthesize nanocrystalline arrays by PVD,the process control factors should be understood in *** simulations of film deposition are an important tool for understanding the mechanisms of film *** this paper,we report a k.C modeling that explicitly represents PVD synthesis of self-assembled *** study how varying critical process parameters such as deposition rate,duration,temperature,and substrate type affect the lateral 2D morphologies of self-assembled metallic islands on substrates,and compare our results with experimentally observed surface morphologies generated by *** simulations align well with experimental results reported in the literature.

关键词： k.netic Monte Carlo Simulation(k.C) nanocrystals nanotechnology

Study of Blood Parasites in Mabuya sp Lizards and Buforegularis Toads in Jebel Awlia and Tuti Island of k.artoum, Sudan

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Journal of Earth Science and Engineering 2015年第1期5卷 86-90页

作者： Muk.tar Hassan Sara A. k. Saeed Omran F. Osman Department of Zoology Faculty of Science University of Khartoum Khartoum 13311 Sudan Natural History Museum Faculty of Science University of Khartoum Khartoum 13311 Sudan

Toads and lizards have been a part of our ecosystems for millions of years and they are good indicators of environmental health. Toads and lizards can be infected by different types of parasites; blood parasites are one of the most important parasites. The present study was conducted to survey and identify different blood parasites in Mabuya sp. lizard and Buforegularis toad in two locations in k.artoum state. Fifteen samples of Mabuya sp and fifteen samples of Buforegularis were collected. All Toads and lizards were dissected and tissue from spleen and liver were examined. The microscopic diagnosis detected Sauroleishmania and Haemogregarina spp parasites in both Mabuya and B. regularis while Microfilariae spp was detected in Mabuya sp. Trypanosoma spp was detected in only one specimen of B. regularis. The results also indicated Sauroleishmania parasites and Haemogregarina spp parasites in the sampled toads and lizards in the two locations. The study of blood parasites and their effects in diversity and health of toads and lizards is necessary to determine the impacts of infections in these animals and the use of the results as indicator of hemoparasites in the environmental as well as the food chain.

关键词： Blood Parasites Toads Lizards Sudan.

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有效的项目管理

丛书名：项目管理核心资源库

2002年

作者：（美）罗伯特·k.威索基（Robert k.Wysock.）等李盛萍常春译

本书分简介、项目准备、项目计划、项目实施、参考资料五部分，讲述了项目管理的发展，如何成为世界级项目经理，什么是项目，什么是项目管理，确定项目范围等。

ISBN: (纸本)7505375423

关键词：项目管理

来源：畅想之星图书光盘版（南... 评论

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创建有效的项目团队

Computer Simulation of an Ammonia-Water Absorption Cycle for Refrigeration: Using a Distillation Tower to Replace the Generator

丛书名：项目管理核心资源库

2003年

作者：（美）罗伯特· k. 威索基（Robert k. Wysock.）曹维武译

本书系统地论述了创建有效的项目团队的各个层面，特别是将项目、项目团队、项目管理过程构成一个整体来进行研究，突破了以往这方面研究的局限性。

ISBN: (纸本)7505381725

关键词：项目管理研究

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Energy and Power Engineering 2020年第6期12卷 237-256页

作者： You-Im Chang Lin-Chia Wu Cherng-Chiao Wu Larry k. Jang Department of Chemical Engineering Tunghai University Taiwan Department of Chemical Engineering California State University Long Beach CA USA

By using a distillation tower as the regenerator, the coefficient of performance (COP) of the ammonia-water absorption refrigeration cycle is calculated in this work. Two types of distillation towers, namely an equilibrium-stage tower with a total condenser and a packed-bed tower with a partial condenser, are used in the cycle. From the simulation results, it is found that both types of distillation towers can successfully increase the COP of the cycle due to increased ammonia concentration in the vapor phase of the ammonia-water refrigerant. It was also found that the tower equipped with a partial condenser provides higher COP than that of the tower equipped with a total condenser. The value of COP can be further increased when the generator is replaced by the packed-bed tower in this water-ammonia absorption cycle. The effects of the mass flow rate ratio of NH3/H2O, stage number, reflux ratio and energy duty of the tower on the COP of the cycle are also studied in the present paper.

关键词： Simulation Ammonia-Water Absorption Refrigeration

Chemical and Microbiological Hazards of Dried Fishes in Bangladesh: A Food Safety Concern

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Food and Nutrition Sciences 2020年第6期11卷 523-539页

作者： Md. Golam Rasul Chunhong Yuan A. k. M. Azad Shah Department of Fisheries Technology Faculty of Fisheries Bangabandhu Sheikh Mujibur Rahman Agricultural University Gazipur Bangladesh Department of Food Production and Environmental Management Faculty of Agriculture Iwate University Morioka Japan

Food safety along with nutrition is an important issue in the present word. Only nutritionally safe food can ensure a healthy balanced diet to consumers. Dried fish is a popular processed fishery product not only in our country, but also in many countries of the world. It is a very good source of dietary protein, lipid and minerals necessary for a healthy body. The consumers of dried fish in national and international level are losing their interest to buy dried fish due to poor quality and safety of the products. Therefore, we reviewed the state of k.owledge regarding the contamination level of dried fish by heavy metals, harmful pesticides, amount of lipid oxidation, and microbial quantity and quality from several districts in Bangladesh. The data reviewed in this article revealed that several dried fishes contaminated with excess amount of heavy metals (Pb, Cd, Cr etc.), pesticide residue (dichlorodiphenyltrichloroethane, heptachlor, endrin, aldrin, dieldrin), higher degree of lipid oxidation, excess amount of total plate count and presence of highly pathogenic E. coli, Salmonella sp. Vibrio sp. were found in few dried fish that may cause substantial human health hazard after consumption. The possible factors of these hazards are traditional drying, use of illegal pesticides with higher dose, lack.of maintaining proper hygiene, sanitation, pack.ging, storage, distribution as well as wat

关键词： Organochlorine Chemicals Heavy Metals Lipid Oxidation Microorganisms Dried Fish

Evaluating the Combined Optimization of Oxygenation and Ventilation in a Patient Simulator

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Journal of Biomedical Science and Engineering 2016年第10期9卷 90-98页

作者： J. k.etschmer C. Bibiano P. Stehle k. Möller Institute of Technical Medicine Furtwangen University Villingen-Schwenningen Germany

The use of mathematical models can aid in optimizing therapy settings in ventilated patients to achieve certain therapy goals. Especially when multiple goals have to be met, the use of individualized models can be of great help. The presented work.shows the potential of using models of respiratory mechanics and gas exchange to optimize minute ventilation and oxygen supply to achieve a defined oxygenation and carbon dioxide removal in a patient while guaranteeing lung protective ventilation. The venti-lator settings are optimized using respiratory mechanics models to compute a respira-tion rate and tidal volume that k.eps the maximum airway pressure below the critical limit of 30 cm H2O while ensuring a sufficient expiration. A three-parameter gas ex-change model is then used to optimize both minute ventilation and oxygen supply to achieve defined arterial partial pressures of oxygen and carbon dioxide in the patient. The presented approach was tested using a JAVA based patient simulator that uses various model combinations to compute patient reactions to changes in the ventilator settings. The simulated patient reaction to the optimized ventilator settings showed good agreement with the desired goals.

关键词： Physiological Model Model Based Optimization Decision Support Patient Simulator