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Magnetoelectric Coupling in Metglas/BaTiO₃/Metglas Lead-Free Magnetoelectric Composites

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Journal of Materials Science and Chemical Engineering 2016年第8期4卷 1-7页

作者： S. D. Patil k. Y. Rajpure A. M. Shaik. Shivaji University Kolhapur India New College Kolhapur India

We report the magnetoelectric (ME) coupling in ME composites composed of NiFe2O4 (NFO) or metglas as magnetostrictive phases and BaTiO3 (BTO) as piezoelectric phase, targeting lead free magetnic field sensors. NFO and BTO phases were synthesized by solid state sintering method and further characterized by using XRD and FESEM techniques. The P-E hysteresis curve shows good ferroelectric behavior with saturation polarization of Ps = 15.87 C/cm2 and coercive electric field of 130 k./cm. The ME response was characterized as a function of dc magnetic field at a fixed frequency. The transverse ME voltage coefficient, αME31 shows 2 times larger magnitude than that of longitudinal ME voltage coefficient, αME31. The maximum αME31 of 37 mV/cm•Oe (@Hdc = 250 Oe) is observed for NFO/BTO/NFO ME composites with thick.ess ratio of tm/tp = 1.0. The ME coupling is further enhanced by replacing NFO layers by highly magnetostrictive metglas layers. Metglas/BTO/metglas laminates show large αME31 value of 81 mV/cm•Oe at relatively lower Hdc of 145 Oe. The present laminates can offer promising opportunities of engineering environmental friendly ME laminate for applications in ME devices such as energy harvester and magnetic field sensors.

关键词： Ferroelectrics Magnetostriction Mechanical Properties Piezoelectricity Strain

CT Thresholds for Spinal Bone Mineral Attenuation to Prioritize Eligible Older Women for Osteoporosis Screening

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Open Journal of Radiology 2024年第2期14卷 92-101页

作者： Seo Yeon k. Orite Bryn Higuchi Hyo-Chun Yoon Lana H. Gimber St. Elizabeths Medical Center Brighton MA USA University of California Irvine CA USA k.iser Permanente Division of Research Oakland CA USA Department of Diagnostic Imaging Hawaii Permanente Medical Group Honolulu HI USA

Introduction: Computed tomography (CT) measurements of bone mineral attenuation may be a useful means to identify older women who should be prioritized for bone mineral density screening. Methods: We compared bone mineral attenuation as measured in the L1 vertebra of CT studies to the results of dual-energy x-ray absorptiometry (DEXA) studies to determine what CT attenuation thresholds might yield a reasonable combination of sensitivity and specificity for the detection of osteoporosis. The study was limited to women between the ages of 65 and 75 years who had a DEXA study and a CT that included the L1 or adjacent vertebra performed within 3 years of the DEXA study. Results: There were 1226 women in this study, of whom 452 (38%) had osteoporosis based on a T-score ≤ −2.5 by DEXA. There were 830 CT studies performed with contrast and 396 studies which were performed without contrast. There was a statistically significant difference in the mean HU of those studies performed without contrast compared to those with contrast (unenhanced mean 103 HU versus 125 HU, p < 0.001). Different CT attenuation thresholds provided the most appropriate combination of sensitivity and specificity for the detection of osteoporosis when comparing CT studies performed without or with IV contrast and when all the CT data were used in aggregate. Conclusion: Different thresholds appear necessary when using the mean CT vertebral attenuation to identify older women for preferential referral for DEXA studies.

关键词： Osteoporosis Bone Mineral Attenuation CT Threshold

Water Runoff Estimation Using Geographical Information System (GIS) for Alrak.mah Basin Valley Northeast of Iraq

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Engineering（科研） 2020年第6期12卷 315-324页

作者： Abdulrazaq k. Abdulwahd Mohammed Ch. Liejy Mohanad A. Sulaiman Nadhir Al-Ansari Technical Institute of Haweeja Northern Technical University Kirkuk Iraq General Commission for Running/Irrigation and Drainage Kirkuk Province Ministry of Water Resources Kirkuk Iraq Lulea University of Technology Lulea Sweden

The lack.of water resources in many regions is the main challenge for the human being and to extended investigations. Water resources controlling and management is essential in the areas depending on the seasonal rainfall. This research aims to estimate the surface water runoff for Basin of Alrak.mah Valley located in the southwestern part of k.rk.k.Province in northeastern of Iraq. Analyzing of Spatial data and Digital Elevation Model (DEM) data has been conducted using Geographic Information System (GIS) to estimate the hydrological properties for the watershed valley with 158.5 k.2 surface area. The results showed that watershed valley type is from the fifth rank.with a longitudinal shape and topography percentage of 0.568. The watershed textures found to be 3.24 and the drain density 1.5 at 3.49 river branching. Finally, the annual estimated surface water retreat according to the morpho-hydro climatic elements found to be 0.01286233 milliard cubic meter.

关键词： Geographic Information Systems (GIS) Digital Elevation Model (DEM) Spatial Data Watershed

The Influence of the Implementation of Trade Facilitation Systems on the Time Required for Creating Delivery Orders: A Case Study of Tema Port

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World Journal of Engineering and Technology 2024年第3期12卷 529-539页

作者： Justice Awosonviri Ak.dia Clement k. Dzidonu David k.ng Boison Philip k.sembe Joseph Gbandi Advanced School of Systems and Data Studies Accra Institute of Technology Accra Ghana Department of Procurement Logistics and Supply Chain Management Ghana Communication Technology University Accra Ghana Department of Computer Engineering Ghana Communication Technology University Accra Ghana College of Education Ohio University Athens Ohio USA

This study evaluated the impact of Ghana’s Integrated Customs Management System (ICUMS), implemented within the National Single Window initiative, on the efficiency of issuing Delivery Orders (DO) at Tema Port. Filling a gap in the existing literature, the research employed a quantitative approach to assess a specific time-related aspect of the cargo clearance process. Employing an Independent t-test on a dataset spanning 2026 Delivery Orders (924 pre-ICUMS and 1102 post-ICUMS) from July 2020 to July 2023, the study investigated ICUMS’s effectiveness in reducing DO issuance time. Results indicate a noteworthy decrease in average DO issuance time, from 11 days pre-implementation to approximately 9 days post-implementation, a reduction validated by statistical analysis through the independent t-test. In light of these findings, the study recommends ongoing refinement of the implementation, reinforcement of trade facilitation measures, and the adoption of best practices from successful global ports. Continuous stak.holder training and regular assessments of ICUMS performance are also endorsed. The study’s implications support the theoretical framework.for Single Window systems and carry significant policy implications, emphasizing the need for collaborative efforts to streamline trade facilitation processes driven by Information Technology. Practically, the results serve as a management tool for stak.holders, highlighting areas for targeted interventions to reduce DO issuance times. Methodologically, this research contributes by applying robust statistical analysis to a specific component within the Time Release Study framework. offering a nuanced understanding of trade facilitation systems’ effectiveness in improving cargo clearance processes.

关键词： Cargo Clearance Container Dwell Time Single Window Trade Facilitation

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组织能力构建过程中学习代理人的作用

管理工程学报 2000年第B12期14卷 34-39页

作者： k.普塞尔迈克尔.格里高瑞徐笑君英国剑桥大学

技术型组织越来越重视能力概念 ,并且许多组织已经完成了能力识别和分析过程。但是 ,在未来保持竞争优势不仅依赖于能力组合过程 ,而且依赖于组织迅速、持续构建能力的能力。本文调查且分析了为什么一些组织在能力构建过程中比其竞争对... 详细信息

技术型组织越来越重视能力概念 ,并且许多组织已经完成了能力识别和分析过程。但是 ,在未来保持竞争优势不仅依赖于能力组合过程 ,而且依赖于组织迅速、持续构建能力的能力。本文调查且分析了为什么一些组织在能力构建过程中比其竞争对手取得更好的成绩的问题。

关键词：能力构建学习代理人技术管理技术型组织组织能力企业组织学习

Design and Construction of a Microcontroller Based Electronic Moving Message Display

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Open Journal of Applied Sciences 2022年第4期12卷 434-454页

作者： Titus Taofk.Ogunseye Godwin Babatunde Egbeyale Adek.nle k. Bello Adegbenro S. Ajani University of Ibadan Ibadan Nigeria k.ara State University Malete Nigeria Bell University Ota Nigeria

LED-based moving-message displays are becoming appreciated among the general public for transmitting information to groups of people quick.y. This work.presents a simple design and implementation of a microcontroller-based electronic moving message display system. The design involves the arrangement of Light Emitting Diodes (LEDs) and the programming of a microcontroller that controls and determines the pattern and session of the display. The implementation of a moving message displays a text containing 22 characters (i.e. WELCOME TO DEPT. OF PHYSICS). The electronic message display helps to pass information, educates, enlightens, facilitates commercial activities through the advertisement and mark.ting of goods and services, description of places, etc. The ease in which it displays information mak.s it a veritable, suitable, and excellent tool for passing information fast and pleasurable to the public. Furthermore, it enhances the response to information in an attractive way and manner in which it displays messages. The microcontroller used in this work.is the PIC16F84A. It belongs to a class of 8-bit microcontrollers of RISC (reduced instructions set) architecture. Its output controls the switching of the relays through a transistor switching stage that switches its sock.t. The LED matrix (array) is arranged in parallel and soldered to a Vero board with the microcontroller and other electronic components, such as resistors, capacitors, transistors, relays, LEDs, diodes, and transformers. In view, this work.served as a means of digging into the technology involved in the use of a microcontroller and some other basic electronic components and enhanced visualization of message display.

关键词： Microcontroller LEDs Transistor Relays Transformer Diodes

Movement Patterns of Metallic Particles in a Single Phase Gas Insulated Busduct with Superimposed Lightning and Switching Impulses

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高电压技术 2008年第12期34卷 2642-2647页

作者： M. Venu Gopala Rao J. Amarnath G.V. Nagesh k.mar S. k.mak.haiah k. D. Srivastava QIS College of Engineering and Technology Ongole 523272 Andhra Pradesh India College of Engineering Jawaharlal Nehru Technological University Kuktrtpally Hyderabad 500085 Andhra Pradesh India Vignan's Institute of Information Technology Visakhapatnam 530046 Andhra Pradesh India C. V. R. College of Engineering Hyderabad Andhra Pradesh India University of British Colombia Vancouver B. C. V6T 1Z4 Canada

Transient over voltages due to lightning and switching surges cause steep build-up of voltage on transmission lines and other electrical apparatus,lik. circuit break.rs,transformers,insulators *** it is necessary for the GIS also to withstand such voltages without break.own of *** system has to be tested under these *** the GIS system operates on power *** Impulse Voltage of 1050 k. and Switching Impulse Voltage of 750 k. superimposed on Power frequency voltages of 75 k.,100 k. and 132 k. are applied to Single Phase Gas Insulated Busduct and the maximum movement of Aluminum,Copper and Silver particles is *** movement patterns are also determined with and without Monte Carlo Simulation for movement of particle in axial and radial *** results show that there is a sudden jump in the movement at the application of impulse on sine *** is because of high magnitude voltage of 1050 k. during 1.2/50 μ*** movement patterns of reduced maximum movement is observed for Switching Impulse superimposed on sine *** results are presented and analyzed.

关键词：重复雷击金属微粒运动形态气相绝缘站粒子污染物

The Effects of Etomidate and Propofol Induction on Hemodynamic and Endocrine Response in Patients Undergoing Coronary Artery Bypass Graft Surgery on Cardiopulmonary Bypass

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World Journal of Cardiovascular Surgery 2012年第3期2卷 48-52页

作者： Anil k.Pandey Neeti Mak.ija Sandeep Chauhan Sambhunath Das Usha k.ran A. k. Bisoi R Lak.hmy Departments of Cardiac Anaesthesia All India Institute of Medical Sciences New Delhi India Departments of Cardiac Biochemistry All India Institute of Medical Sciences New Delhi India Departments of Cardiac Surgery All India Institute of Medical Sciences New Delhi India

Aim: To compare the effects of propofol and etomidate induction on hemodynamic parameters and serum cortisol levels in patients with normal left ventricular function undergoing elective coronary artery bypass graft surgery on cardiopulmonary bypass. Material and Method: After approval from the Institute Ethics committee hundred American Society of Anesthesiologists (ASA) grade II or III patients undergoing scheduled coronary artery bypass surgery on cardiopulmonary bypass were enrolled in the study. Patients were allocated randomly to receive either propofol or etomidate for anesthesia induction. Anesthesia was maintained in both groups with sevoflurane, vecuronium bromide for muscle relaxation (0.1 mg/k., boluses) and fentanyl up to a total dose of 20 mcg/k.. Result: The baseline serum cortisol values were within normal limits in both the groups. The serum cortisol levels in the propofol group increased more than two fold, whereas the values in the etomidate group decreased by close to fifty percent on weaning from cardiopulmonary bypass (CPB). There was no significant difference in serum cortisol levels in the two groups at twenty-four hours after induction, although the values were close to double the baseline levels. Hemodynamically, etomidate group was more stable than propofol group following induction of anesthesia (P < 0.05). Conclusion: The surge in serum cortisol levels on the initiation of CPB seen after the use of propofol is prevented by the use of etomidate. Serum cortisol levels in both groups are well above the baseline at twenty-four hours without any untoward effects. Etomidate provides more stable hemodynamic parameters when used for induction of anesthesia as compared to propofol.

关键词： Etomidate Propofol Coronary Artery Bypass Grafting (CABG) Cardiopulmonary Bypass (CPB)

Efficient Application of the Radiance Enhancement Method for Detection of the Forest Fires Due to Combustion-Originated Reflectance

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Journal of Environmental Protection 2021年第10期12卷 717-733页

作者： Rehan Siddiqui Rajinder k. Jagpal Sanjar M. Abrarov Brendan M. Quine Epic College of Technology Mississauga Canada Department of Earth and Space Science and Engineering York University Toronto Canada Department of Physics and Astronomy York University Toronto Canada Thoth Technology Inc. Algonquin Radio Observatory Pembroke Ontario Canada

The existing methods for detection of the cloud scenes are applied at relatively small spectral range within shortwave upwelling radiative wavelength flux. We have reported a new method for detection of the cloud scenes based on the Radiance Enhancement (RE). This method can be used to cover a significantly wider spectral range from 1100 nm to 1700 nm by using datasets from the space-orbiting micro-spectrometer Argus 1000. Due to high sunlight reflection of the smok. originated from the forest or field fires the proposed RE method can also be implemented for detection of combustion aerosols. This approach can be a promising technique for efficient detection and continuous monitor of the seasonal forest and field fires. To the best of our k.owledge this is the first report showing how a cloud method can be generalized for efficient detection of the forest fires due to combustion-originated reflectance.

关键词： Radiance Enhancement Clouds Forest Fire Radiative Transfer Model Line-By-Line Calculation Micro-Spectrometer