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Optimisation of Direct Expansion (DX) Cooling coils Aiming to Building Energy Efficiency

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Journal of Building Construction and Planning Research 2015年第2期3卷 47-59页

作者： Liang Xia Tong Yang Yue Chan Llewellyn Tang Yung-Tsang Chen Department of Architecture and Built Environment University of Nottingham Ningbo China Ningbo China School of Mathematical Sciences University of Nottingham Ningbo China Ningbo China Department of Civil Engineering University of Nottingham Ningbo China Ningbo China

Efficient Air Conditioning (A/C) system is the key to reducing energy consumption in building operation. In order to decrease the energy consumption in an A/C system, a method to calculate the optimal tube row number of a direct expansion (DX) cooling coil for minimizing the entropy generation in the DX cooling which functioned as evaporator in the A/C system was developed. The optimal tube row numbers were determined based on the entropy generation minimization (EGM) approach. Parametric studies were conducted to demonstrate the application of the analytical calculation method. Optimal tube row number for different air mass flow rates, inlet air temperatures and sensible cooling loads were investigated. It was found that the optimal tube row number of a DX cooling coil was in the range of 5 - 9 under normal operating conditions. The optimal tube row number was less when the mass flow rate and inlet air temperature were increased. The tube row number increased when the sensible cooling load was increased. The exergy loss when using a non-optimal and optimal tube row numbers was compared to show the advantage of using the optimal tube row number. The decrease of exery loss ranged from around 24% to 70%. Therefore the new analytical method developed in this paper offers a good practice guide for the design of DX cooling coils for energy conservation.

关键词： Optimal Tube Row Number Entropy Generation Minimization Direct Expansion (DX) Cooling coil Building Energy Efficiency

AN EFFICIENT RF coil FOR GENERATING A CIRCULAR POLARIZED MAGNETIC FIELD

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Journal of Shanghai Jiaotong university(Science) 1996年第2期1卷 77-80页

作者： Ding Meixin Su Zhongyi(Dept. of Electrical Engineering) (Dept. of Information and Control Engineering)Zheng Jie(Dept. of Electrical Engineering)

The configuration, magnetic field calculation and field distribution of the birdcage RF coil is pre-sented. This type of coil can produce a circular Polarized magnetic field. It has been widely used in the MRIsystem for head and whole-body imaging which can achive nearly optimal RF field uniformity and signal-to-noise ratio(SNR). The rnagnetic field is evenly distributed over the coil. The features of the birdcage coil areanalyzed on the basis of numerical simulation and experimental studies.

关键词： efficient circular Polarized uniform radiofrequency birdcage coil magnetic field distribution

在coil中BHP的HO_(2)^(-)浓度对氯的利用率和激光功率的影响

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强激光与粒子束 2000年第B11期12卷 43-46页

作者：刘万发王科徐增和郭敬为中国科学院大连化学物理研究所大连110信箱大连116023

对 coil中碱性过氧化氢 ( BHP)溶液中的 HO2 -浓度进行了理论计算和实验测量 ,得到了 HO2 -浓度随不同浓度的 KOH和 H2 O2 以及不同比例 (体积 )配比的变化规律 ,并做了不同浓度HO2 -对氯的利用率和激光输出功率影响的实验 ,获得的结果... 详细信息

对 coil中碱性过氧化氢 ( BHP)溶液中的 HO2 -浓度进行了理论计算和实验测量 ,得到了 HO2 -浓度随不同浓度的 KOH和 H2 O2 以及不同比例 (体积 )配比的变化规律 ,并做了不同浓度HO2 -对氯的利用率和激光输出功率影响的实验 ,获得的结果对优化

关键词： coil 碱性过氧化氢 HO_(2)^(-) 氯的利用率

Using Neural Networks to Predict Secondary Structure for Protein Folding

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Journal of Computer and Communications 2017年第1期5卷 1-8页

作者： Ali Abdulhafidh Ibrahim Ibrahim Sabah Yasseen College of Science Al-Nahrain University Baghdad Iraq College of Information Engineering Al-Nahrain University Baghdad Iraq

Protein Secondary Structure Prediction (PSSP) is considered as one of the major challenging tasks in bioinformatics, so many solutions have been proposed to solve that problem via trying to achieve more accurate prediction results. The goal of this paper is to develop and implement an intelligent based system to predict secondary structure of a protein from its primary amino acid sequence by using five models of Neural Network (NN). These models are Feed Forward Neural Network (FNN), Learning Vector Quantization (LVQ), Probabilistic Neural Network (PNN), Convolutional Neural Network (CNN), and CNN Fine Tuning for PSSP. To evaluate our approaches two datasets have been used. The first one contains 114 protein samples, and the second one contains 1845 protein samples.

关键词： Protein Secondary Structure Prediction (PSSP) Neural Network (NN) α-Helix (H) β-Sheet (E) coil (C) Feed Forward Neural Network (FNN) Learning Vector Quantization (LVQ) Probabilistic Neural Network (PNN) Convolutional Neural Network (CNN)

Pulsed Magnetic Field Measurement Outside Finite Length Solenoid: Experimental Results &Mathematical Verification

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Journal of Electromagnetic Analysis and Applications 2013年第10期5卷 371-378页

作者： Shibaji Basu Siddhartha Shankar Pany Partha Bannerjee Sabyasachi Mitra Accelerator & Pulse Power Division Bhabha Atomic Research Centre Mumbai India Accelerator & Pulse Power Division Bhabha Atomic Research Centre Vishakapatnam India Electronics & Instrumentation Services Division Bhabha Atomic Research Centre Mumbai India Energetics & Electromagnetics Division Bhabha Atomic Research Centre Vishakapatnam India

The paper deals with magnetic field mapping outside a finite length solenoid electromagnet, by an in-house designed and calibrated inductive pick-up or search coil. The search coil is calibrated in a unique methodology based on the azimuthal magnetic field component generated by a straight wire. This unique calibration technique helps us to avoid additional circuitry to integrate the signal obtained from search coil. The methodology proves advantageous in diffusion, implosion studies where the signal frequency changes with dimension and material of experimental job-piece (hollow metal tube). Remedial measures have been taken to avoid electrostatic capacitive pick-up (which eventually exacerbates with integration) keeping measurement simple and accurate. The experimentally measured field values have also been compared with electromagnetic field results obtained from mathematical calculations and finite element based simulations. Two different mathematical approaches have been demonstrated for field computation based on Biot-Savart Law. Both the methods have taken into account the exact geometry of the solenoid, including the inter-turn gaps. The methods use appropriate combination of closed-form mathematical expression and numerical integration techniques and are capable of determining all the vector components of magnetic field anywhere around the finite length solenoid. The mathematical computations are equally significant contributions in the paper especially because exact determination of magnetic fields outside finite length solenoids has not been discussed in sufficient specific details in already existing literature. The mathematical computations, finite element simulations and experimental verification together provide a holistic solution to magnetic field determination problems in pulse power applications that have not been discussed in available literature or books in specific details.

关键词： Pulsed Magnetic Field Biot-Savart Law Search coil

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在coil中碘量变化与激光功率波形的关系

强激光与粒子束 2000年第B11期12卷 59-62页

作者：刘万发徐文刚赵彤桑凤亭中国科学院大连化学物理研究所大连110信箱大连116023

针对碘量在一定范围内变化对激光功率影响不敏感 ,采用碘量变化的方法 ,通过对大量的 2 50 mmol/ s列管式射流氧发生器的出光实验的分析 ,得到了激光功率波形随碘量变化的实验规律。这一实验结果可用于根据功率波形变化来调节最佳碘量... 详细信息

针对碘量在一定范围内变化对激光功率影响不敏感 ,采用碘量变化的方法 ,通过对大量的 2 50 mmol/ s列管式射流氧发生器的出光实验的分析 ,得到了激光功率波形随碘量变化的实验规律。这一实验结果可用于根据功率波形变化来调节最佳碘量。并对其机理进行了理论分析。

关键词： coil 激光功率波形碘发生器

The Research on the Quick Discharge Circuit of Shunt Capacitor

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Journal of Power and Energy Engineering 2014年第4期2卷 579-585页

作者： Shuheng Dan Lei Ning Department of Electrical Engineering Shanghai University of Electric Power Shanghai China

Shunt capacitor is the main method to intensively compensate reactive power in the power system. The external discharge circuit, commonly discharge coil which is an inductance coil with low resistance, must be allocated to the large capacity of capacitor. This paper calculates and compares two kinds of circuit, capacitor placed with a discharge coil or a resistance, to find the best way to discharge the residual charge of capacitor. Through the study, in the under damped case, these two kinds of circuit present different discharge properties. In over damped mode, their discharge properties are similar.

关键词： Discharge coil Discharge Property Capacitor

Giant Serpentine Cerebral Aneurysm of the Middle Cerebral Artery: Case Report

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Open Journal of Medical Imaging 2017年第1期7卷 9-16页

作者： Abdulrahman M. Al Shamy Mohammed D. Alsahafi Muhammed A. Alghamdi Abdullah A. Alshamrani Roaa N. Filfilan Radiology Department KAMC-NG Jeddah KSA College of Medicine Umm Alqura University Makkah KSA

A 43-year-old male presented with severe intermittent headaches since two years accompanied by multiple episodes of generalized seizures and left hand weakness. MRI scan and cerebral angiography confirmed the diagnosis of a giant serpentine cerebral aneurysm arising from the middle cerebral artery. The patient was admitted for a possible cerebral embolization after undergoing a Balloon Occlusion Test (BOT). Since he tolerated the occlusion test, he underwent coil embolization afterwards with successful occlusion followed by an uneventful recovery and no complications. Later on, the patient was discharged home in a stable and good general condition without any neurological deficits. A six-month angiography follow-up revealed a complete occlusion with no re-canalization of the coiled giant serpentine aneurysm. Therefore, we concluded that parent artery occlusion is a good and safe procedure providing that the patient tolerated both the occlusion and the hemodynamic stress tests.

关键词： Aneurysm Giant Interventional Neuroradiology Giant Serpentine Aneurysm Balloon Occlusion Test Parent Artery Sacrifice coil Embolization Endovascular

Application of the HES in Angular Analysis

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Journal of Sensor Technology 2012年第2期2卷 87-93页

作者： Witsarut Sriratana Riichi Murayama Lerdlekha Tanachaikhan Department of Intelligent Mechanical Engineering Faculty of Engineering Fukuoka Institute of Technology Fukuoka Japan Faculty of Engineering Ramkhamhaeng University Bangkok Thailand

This study presents an analysis of the relationship of angles and trigonometric functions by applying Hall Effect Sensor (HES). Electromagnetic density of 4.624 mT can be generated from the Helmholtz coil. Angle of shaft which was installed at the center of the Helmholtz coil perpendicularly to horizontal plane was considered as reference and can be rotated. In this study, an experiment for measuring the angle of shaft declination on X-axis was carried on. Ranges of measurement were related to the angle resolution between –15 to 15 degree with 1 step degree interval from perpendicular angle (Y-axis). Analysis of the relationship between shaft declination and electromagnetic field was performed using HES device which was installed on the top of shaft and perpendicularly to reference electromagnetic field [1,2]. The angle declining from the origin which was normal to magnetic field can be determined by measuring the relationship between Hall voltage and magnetic field. Normally, electromagnetic field is nonuniform and varied by point in Helmholtz coil radius. Shaft angles on X-axis were measured for assessing the repeatability of system developed. Five values of results were measured repeatedly at the same input. It can be observed that the system developed can provide the results with the best accuracy and reliability of 95%.

关键词： Angle Axis Decline Degree Electromagnetic Field Helmholtz coil HES Shaft