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Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Pulp & Paper is the property of China Pulp & Paper Magazines Publisher and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In some engineering applications and accidents, the detonation performance of explosives may change if subjected to multiple shocks and releases. Therefore, an experimental loading device with multiple shocks and releases is needed in order to study the detonation response of explosives under complex loads. In this paper, an experimental detonation loading device that can achieve complete release of shock-releasereshock is proposed and designed. The device is optimized through numerical simulations, and the accuracy of the numerical simulation is validated by the corresponding experiments. The results indicate that the designed detonation loading device can achieve complete release of shock-release-reshock loading procesure of TATB-based insensitive explosives, where the detonation loading device drives tungsten magnesium double-layer flyers. The design provides a new experimental technique for further study on the detonation response of explosives under complex loads and multiple shocks. [ABSTRACT FROM AUTHOR]

Copyright of University Chemistry is the property of Peking University, College of Chemistry & Molecular Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The gradual depletion of shallow resources necessitates the imperative shift towards deep mining. In deep mining, dynamic disasters, such as rockburst, caused by high in-situ stress and other complex geological environments, have persistently posed a significant challenge to the safe and efficient extraction of deep minerals. Despite the longstanding occurrence of rockburst disasters, they have not been effectively resolved due to limitations in their occurrence mechanisms and monitoring methods. In this paper, the evaluation system and the prevention and control technology of rockburst were systematically summarized and concluded through literature research. The current research progress shows that there are many evaluation systems of rockburst, which can evaluate and predict the grade and tendency of rockburst disasters well. Regarding rockburst prevention and control systems, they can generally be classified into passive and active control technology based on the timing of disaster management and protective mechanisms. The overall planning concept was developed based on mining plan optimization and stress environment reconstruction, providing a new idea and method for rockburst prevention and control in deep mining of metal mines. Finally, taking the deep mining of Sanshandao Gold mine as the background, the advantages and effects of the unloading mining scheme in rockburst control and prevention under the integrated planning concept were verified, which provided an effective reference for the advanced intervention and active prevention and control of rockburst in deep mining of metal mines in the future. [ABSTRACT FROM AUTHOR]

Copyright of Journal of International Chinese Teaching is the property of Beijing Language & Culture University Press Co. Ltd. and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The eastern Himalayan syntaxis is one of the regions having the most intense tectonic activities, the most complex geological conditions, and the most frequent geohazards in the world. The planning and construction of engineering projects are faced with four types of catastrophic geo-safety risks, including tectonic faulting in the plate tectonic belt, disaster occurrence of the deep-buried tunnels, instability of loose mountains, and regional geological disaster chain. It is a critical topic in the field of engineering geology how to select relatively stable and safe sites in active tectonic zones to minimize the geo-safety risks of planning, construction, and operation of engineering projects. This paper summarized the major geo-safety problems in the eastern Himalayan syntaxis. Accordingly, it revealed that traditional site selection theories hardly satisfy the requirements of the engineering projects in the eastern Himalayan syntaxis area. The site selection encounters geo-safety challenges caused by unclear geological evolution process and construction, prominent disaster risk of tectonic activity and strong earthquake, weak research on the deep tectonic stress field and disaster evaluation, and severe ultra-high-elevation and ultra-long-runout geological disaster chain. Thus, this paper suggested the main research directions of the site selection from five aspects: (1) regional geological evolution and engineering geological problems, (2) active fault and engineering safety risk, (3) complex in-situ stress field and engineering disaster risk, (4) engineering risk of regional geological disaster chain, and (5) theory and method of site selection in eastern Himalayan syntaxis. This paper provides ideas for improving the risk assessment and prevention methods of site selection of engineering projects. [ABSTRACT FROM AUTHOR]

Copyright of Hydrogeology & Engineering Geology / Shuiwendizhi Gongchengdizhi is the property of Hydrogeology & Engineering Geology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper focuses on the reform of experimental teaching in electronic packaging technology courses, and establishes multi-dimensional teaching objectives based on knowledge, ability, and ideological and political education. This paper constructs a full packaging process knowledge system led by the forefront of technology, forms an online and offline multimodal experimental teaching mode using modern information technologies such as virtual simulation and SPOC video, and establishes a scientific and comprehensive evaluation system for experimental teaching, Guides value throughout the entire process of talent cultivation. This reform has greatly improved students' self-learning ability, problem-solving ability, and exploratory innovation ability. [ABSTRACT FROM AUTHOR]

The segment assembly problem of shield tunnel in the transition curve part is always a difficult problem in the construction process because of the complex shape of the transition curve and the changeable points of segment assembly. Based on the requirement of staggered assembling and wedge segment characteristics, this paper puts forward a method within the plane to complete every piece of assembling construction by calculating and judging the condition of error control with comprehensive comparison of standard ring and wedge ring combination, and fit out design and varification methods, which meets the specification and control index and guarantees ing uniform linear axis in segment assembling. According to the actual engineering needs, the maximum allowable deviation control method and the segment assembly optimization measures near the slow circle point are proposed, and the accuracy and applicability of the method are proved by the shield tunnel between Wanchai North Station and Wanchai station of Zhuhai Zhuhai-mechanical line, which provides a theoretical basis for the control of segment assembly quality on the transition curve. [ABSTRACT FROM AUTHOR]

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Reducing the effect of unwanted vibrations is an important topic in many engineering applications. In this paper we describe some recent developments in the area of passive vibration mitigation. This is based on a new device called the inerter which can be exploited in a range of different contexts. In this paper we consider two recent examples; (i) where a flywheel inerter is combined with a hysteretic damper, and (ii) in which a pivoted bar inerter is developed for a machining application. In both cases, experimental test results show that the devices can outperform existing methods. [ABSTRACT FROM AUTHOR]

This paper discusses the practice and application of IRIS configuration management in railway signal engineering projects in view of the practice in railway projects. The technology management means related to IRIS configuration management are used to ensure product traceability, safety and reliability in the project life cycle, thus playing a very important supporting role. [ABSTRACT FROM AUTHOR]

Copyright of China Medical Education Technology is the property of China Medical Education Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Guangdong University of Technology is the property of Journal of Guangdong University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The aeroengine control system is a safety critical system for aeroengine, crucial for generating reliable thrust or power within the entire flight envelope of the engine. This paper presents the evolution of the aeroengine control system, summarizes and analyzes the development of three key system-level technologies. including architecture design, control law design, and fault diagnosis and condition monitoring design, as well as simulation enabling technologies. The discussion on the applicability of these technologies in engineering is then conducted. The prospects for future development directions and key research areas are finally explored, providing a valuable reference for the design of next generation aeroengine control systems. [ABSTRACT FROM AUTHOR]

In order to solve the problems of slow modeling of design model, poor integration of modeling system in the construction of traditional railway electronic sand table, based on AnyCAD library, this paper studied the methods of modeling, conversion and integration of bridge form by reading the component parameters in bridge form, and studied the method of modeling and integration of tunnel assembly based on tunnel component library and statistics of tunnel assembly table. Besides, the methods and requirements of three-dimensional scene construction and three-dimensional midline production of electronic sand table were discussed. Through experimental statistics, compared with traditional parametric modeling, the efficiency of bridge calculation modeling is improved by 78.7 times, and the efficiency of tunnel assembly modeling is improved by nearly 14.7 times, which realizes the rapid modeling of bridge and tunnel design models. [ABSTRACT FROM AUTHOR]

The "new engineering" concept requires that in addition to laying a solid professional foundation, engineering colleges and universities in China should also pay attention to improving the humanistic quality and developing a professional ethics education in training the engineering and technical talents. One important way is to carry out the engineering ethics education. By referring to the mature case-teaching ideas around the world and combining the practical experience accumulated in recent years, this paper focuses on the curriculum development and teaching reform of engineering ethics for students studying biological and medical engineering, from the perspectives of case selection and teaching method innovation. It also introduces some typical case studies, and summarizes the teaching effect analyzed from questionnaire.

In order to promote the development and application process of suspended permanent maglev monorail transportation system, China has built suspended permanent maglev monorail transportation system engineering test line, Xingguo engineering test line, and the line has made useful explorations on many key technologies in the engineering process of the system. The key technical contents such as the overall layout of the test line, the suspension guidance and drive system, track beam and turnout, manufacturing process, which are different compared to the permanent maglev monorail transit and the conventional rubber wheel suspended monorail transit, are studied emphatically in this paper. The research shows that, under the premise of meeting the basic requirements of the test line, the reasonable overall layout reduces the land and engineering investment at the greatest extent. The innovative design of core systems, such as permanent maglev, realizes the stable suspension guidance and drive of the test line vehicles, and the design of key systems such as track beam bridge, turnout and processes lays the foundation for the safe operation of the test line. [ABSTRACT FROM AUTHOR]

Copyright of China Harbour Engineering is the property of Editorial Office of China Harbour Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Harbour Engineering is the property of Editorial Office of China Harbour Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Harbour Engineering is the property of Editorial Office of China Harbour Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The traditional differential evolution（DE） algorithm balanced global exploration and local exploitation inadequately, and had problems with easily falling into local optimal solutions, low solution accuracy and slow convergence speed. Therefore, this paper proposed a differential evolution algorithm based on random neighborhood mutation and optimal opposition-based learning（RNODE） and analyzed for its complexity. Firstly, the algorithm generated a random neighborhood for each individual in the current population, and used the global best individual to guide the neighborhood best individual to generate a composite basis vector, combined with an adaptive update mechanism of the control parameters to constitute a random neighborhood mutation strategy, which enabled the algorithm maintained its exploration ability and guided the population towards the optimal direction. Secondly, to further help the algorithm jump out of the local optimum, the algorithm performed the optimal opposition-based learning strategy on the poorer individuals to expand the search area. Finally, this paper compared RNODE with 9 algorithms to verify the effectiveness and advancement of RNODE. The experimental results on 23 benchmark functions and 2 real-world engineering optimization problems show that the RNODE algorithm has a higher convergence accuracy, faster speed and a greater stability. [ABSTRACT FROM AUTHOR]

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Construction Technology is the property of Railway Construction Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In this paper,the stability of the roof-cutting strip-shaped mine column at the top of the Stage open-stope backfilling method of the Jinchanghe ZnV3 orebody is taken as the research object. By analyzing the distribution law of the stress state of the stope at different stages, combined with the current situation of the anchoring support of the broken surrounding rock of the roof, in order to improve the stability of the strip-shaped mine column, the method of combining theoretical analysis and numerical simulation is used for research and analysis. The research results show that the optimization scheme of alternately arranging 4 m wide drilling chamber and 3 m wide strip-shaped mine column on both sides of the roof-cutting contact channel can effectively share the influence of stress concentration on the strip-shaped mine column and greatly improve the stability of the strip-shaped mine column. The optimization scheme changes the roof support area and further improves the stability of the roof after the goaf. According to the research results, industrial experiments were carried out to verify the feasibility of the optimization scheme, which is of great significance to safety production and can be applied in mines. The optimization of the roof cutting project further improves the stability of the roof under the condition of improving the stability of the strip-shaped mine column, which can provide a reference for similar mines. [ABSTRACT FROM AUTHOR]

Copyright of Railway Standard Design is the property of Railway Standard Design Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Advances in New & Renewable Energy is the property of Editorial Office of Advances in New & Renewable Energy and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Carsologica Sinica is the property of Institute of Karst Geology, CAGS and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Coal Science & Technology (0253-2336) is the property of Coal Science & Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Ordnance Industry Automation is the property of Editorial Board for Ordnance Industry Automation and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Control Theory & Applications / Kongzhi Lilun Yu Yinyong is the property of Editorial Department of Control Theory & Applications and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Harbour Engineering is the property of Editorial Office of China Harbour Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Ordnance Equipment Engineering is the property of Chongqing University of Technology and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of University Chemistry is the property of Peking University, College of Chemistry & Molecular Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

To improve the local mining and global search ability of quantum-behaved particle swarm optimization algorithm ( QPSO), this paper proposed an improved QPSO algorithm( DSQPSO). DSQPSO algorithm introduced the double strategies co-evolution to adjust the particle position update formula. Firstly, in order to fully reflect the advantage of individual exploration and the characteristic of collective guidance, this paper put forward two kinds of ideas of attraction points to achieve better integration of individuals and the swarm as well as information exchange. Secondly, it redefined the search scope of the particle through considering the relationship between the optimal average position and the global optimum and individual's historical optimum respectively. Moreover, in the iterative process, DSQPSO used the random perturbation mechanism to adjust the global optimal position in order to help the diversity of the swarm to be preserved. Based on 18 test functions, this paper compared DSQPSO with PSO, QPSO, RQPSO and LQPSO in convergence accuracy and robustness. Furthermore, in terms of the optimization results, it compared the improved algorithm with eight intelligent algorithms on two practical engineering optimization problems. Experiments indicate that whether in benchmarking or in engineering application, DSQPSO has obvious advantages in calculation precision and convergence effect. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Engineering Management / Gongcheng Guanli Xuebao is the property of Journal of Engineering Management Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of China Harbour Engineering is the property of Editorial Office of China Harbour Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Journal of Beijing University of Technology is the property of Journal of Beijing University of Technology, Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Telecommunication Engineering is the property of Telecommunication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Investigation & Surveying is the property of Railway Investigation & Surveying Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Railway Signalling & Communication Engineering is the property of Railway Signalling & Communication Engineering and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)