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121.
122.
Jeremy Howells 《Industry and innovation》1999,6(1):111-129
The paper discusses the process of externalization and contracting out of research and technology, in particular the outsourcing of R&D and technical activity formerly undertaken by manufacturing and service companies and now contracted out to other firms and specialist organizations. The growth in the external sourcing of R&D, design and other technical activities by firms has contributed to the evolution of new research and technical markets which have important implications for current conceptualizations of “systems of innovation”. 相似文献
123.
Vivian E. Ferry Jeremy N. Munday Harry A. Atwater 《Advanced materials (Deerfield Beach, Fla.)》2010,22(43):4794-4808
This paper reviews the recent research progress in the incorporation of plasmonic nanostructures with photovoltaic devices and the potential for surface plasmon enhanced absorption. We first outline a variety of cell architectures incorporating metal nanostructures. We then review the experimental fabrication methods and measurements to date, as well as systematic theoretical studies of the optimal nanostructure shapes. Finally we discuss photovoltaic absorber materials that could benefit from surface plasmon enhanced absorption. 相似文献
124.
Jeremy Rutman 《Electrochimica acta》2007,52(20):6073-6083
The placement of reference electrodes in solid state ionic conductors is not as flexible as in liquid state electrochemistry. This is in particular a problem when material from the gas phase is involved, as in solid oxide fuel cell. Many of the arrangements used are problematic: either they produce results that are very sensitive to electrode placement, change the potential distribution, do not provide a uniform current density and overpotential at the electrode or require delicate patterns liable to fail. We here present a new approach suitable for thin layer SOFC. It includes a calibration procedure derived from numerical simulations in combination with experiments. This allows the use of the common three-electrode arrangement on thin solid electrolyte (SEs) where the reference electrode is placed side by side with the working electrode, on an extension of the thin layer SE. This is so despite the sensitivity of that arrangement to both misalignment of the electrodes and to a difference in the impedance of the two current carrying electrodes. The misalignment tolerated, with the present method, may exceed the SE thickness. The allowed misalignment increases with the electrode/SE impedance ratio. The method copes also with the difference in the electrode impedance. Two special configurations are discussed in which the calibration is not required. However, these require a more accurate preparation technique of the cell. 相似文献
125.
Jeremy Penzer 《时间序列分析杂志》2007,28(5):629-645
Abstract. An alternative to leave‐k‐out diagnostics for detecting patches of outlying points in time series is developed. We propose that unusual behaviour should be modelled by the addition of shocks. By including shocks in the transition equation of a state space model, we admit the possibility of a persistent change associated with a patch of outliers. Persistent change may take the form of a level shift or a change in seasonal pattern. We provide an efficient mechanism for computing diagnostic statistics associated with the addition of k shocks using a simple adaptation of the Kalman filter. Statistics for detecting unspecified patterns of shocks and an interpretation of the output of the associated smoothing algorithm are derived. Illustrations using real series are given. 相似文献
126.
Skinner Darlene M.; Martin Gerard M.; Scanlon Christa-Jo; Thorpe Christina M.; Barry Jeremy; Evans John H.; Harley Carolyn W. 《Canadian Metallurgical Quarterly》2001,115(1):220
The ability of rats to return to the start location was examined with a 4-arm radial water maze. The task required rats to find 2 hidden platforms in sequence. Rats were released from 1 of 3 arms and there was a platform located in the fourth arm. Once a rat found this platform, a 2nd platform was raised in another location, which was either the start location, for 1 group, or another fixed location, for a control group. Across 3 experiments, all rats learned the location of the 1st fixed platform in 80 to 120 trials. However, rats had difficulty finding a 2nd platform if it was at the start location. Control groups revealed that rats could learn 2 platform locations and that the difficulty in learning to return to the start location did not seem to be attributable to its aversive nature. In separate groups, exposure to the start location was increased by starting the rats from an initially stable platform. Rats still did not readily learn to return to the start location. The authors suggest that start location, when varied, cannot readily be used to define the location of a hidden platform. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
127.
128.
Describes how, in the ancient Near East, conceptions of individual suffering and absence of divine justice gave rise to wisdom literature. These motifs reflected both observation and an attempt to understand the enigmatic presence of depression, personal tragedy, and social injustice. The dilemma arising from the contradiction between belief and observation was a central theme in the Biblical books of Job and Ecclesiastes. This conflict posed a problem in the counseling relationship between the comforter and sufferer and is relevant to contemporary psychotherapy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
129.
Jeremy Bowman 《Polymer Engineering and Science》1997,37(4):674-691
Electrofusion joining is now an essential and widely used method to assist in the creation of polyethylene pressure pipe systems. The process of electrofusion joining is reviewed by examining the experimental and some computer simulation literature relating to the temperature and melt pressure changes during the fusion process, and on how varying fusion time and pipe/fitting gap influences the strength of electrofusion joints. From this literature review, four key stages in the joining process are identified. First, an incubation period where the joint has no strength. Second, a joint formation and consolidation stage where an increasing joint temperature aids molecular diffusion to both increase the joint strength and promote a more ductile mode of failure. A plateau region then follows where the joint strength, and ductility, remain reasonably constant despite the fusion time increasing. This plateau is thought to allow some welding variables, such as gap, to have only a small influence on joint strength (for gap maintained within reasonable limits). Finally there is a cooling stage where the joint bridging “tie molecules” become locked into either side of the joint. It is these tie molecules that give the joint its ductility and strength. The concluding section of the review notes some of the important on-site practices that, if followed, allow electrofusion joints to acquire their good strength properties, and hence give polyethylene pressure pipe systems of a high integrity. 相似文献
130.
Editor's NoteIn 2002, Jeremy Hight was involved in the project 34 North 118 West, one of the seminal works of what became known as locative media. He also wrote one of the seminal texts of the field, Narrative Archaeology. Here he discusses the process of conceptualizing and making the work and how it has fueled his latest projects with locative narratives.—Maria Miranda 相似文献