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101.
Researchers on organisational ambidexterity have proposed several solutions to address the potential conflicts between exploration activities and exploitation activities. Unlike simultaneous ambidexterity, sequential ambidexterity – defined as temporal switching between exploration and exploitation – has not been examined fully, and the conditions under which this temporal switching can be successful are unclear. This paper proposes the concept of temporal switching capability to better understand the process by which sequential ambidexterity is executed. In addition, we hypothesise that performance effects are contingent upon firm-specific factors: a firm’s business strategy and absorptive capacity. Utilising three sources of data – a secondary database, annual reports and a survey administered to 145 firms in the electronics industry with 10-year observations – we find support for our hypotheses. The results show that the temporal switching capability positively relates to new product performance and that business strategy type and absorptive capacity have moderating effects. The results are meaningful in both theory and practice. 相似文献
102.
PURPOSE: To compare admission data and academic performances of medical students younger and older than 25, and to qualify older students' experiences and perceptions in medical school. METHOD: The authors reviewed 1988-1991 data for applications to the McGill University Faculty of Medicine. Data included GPAs and MCAT scores, as well as ratings for reference letters, autobiographical statements, and interviews. For those same years, the authors measured students' academic performances in the preclinical and clinical years. The authors compared the data by students' age: "younger" students, aged 17 to 24; and "older" students, aged 25 and above. All enrolled students took the Derogatis Stress Profile, and the older students participated in focus groups. RESULTS: The older applicants had lower GPAs and MCAT scores, but higher interview and reference letter ratings. For older accepted students, basic science course scores were lower than those of younger students, but clinical scores did not differ significantly between the groups. The two groups had similar stress levels, although older students tested lower in driven behavior, relaxation potential, attitude posture, and hostility. In focus groups, the older students spoke of learning style differences, loss of social support, and loss of professional identity. CONCLUSION: Different scores in admission criteria suggest that McGill uses different standards to select older medical students. Older students admitted under different criteria, however, do just as well as do younger students by their clinical years. A broad-based study of admission criteria and outcomes for the older student population is warranted. 相似文献
103.
An amplitude-sensitive optical heterodyne polarimeter was set up to monitor noninvasively the aqueous glucose concentration in a rabbit's eye. A Zeeman laser in conjunction with a Glan-Thompson analyzer was used to generate an optical heterodyne signal. The amplitude of the heterodyne signal linearly related to the optical rotation angle of the aqueous glucose. The concentration of the aqueous glucose in a rabbit's eyeball was measured in vivo. There was a 30-min time delay between observations of aqueous glucose and blood glucose. The detection capability and the reproducibility of the experiment are demonstrated and discussed. 相似文献
104.
神经网络已经在模式识别、自动控制及数据挖掘等领域取得了广泛的应用,但学习方法的速度不能满足实际需求。传统的误差反向传播方法(BP)主要是基于梯度下降的思想,需要多次迭代;网络的所有参数都需要在训练过程中迭代确定,因此算法的计算量和搜索空间很大。ELM(Extreme Learning Machine,ELM)是一次学习思想使得学习速度提高很多,避免了多次迭代和局部最小值,具有良好的泛化性能、鲁棒性与可控性。但对于不同的数据集和不同的应用领域,无论ELM是用于数据分类或是回归,ELM算法本身还是存在问题,所以本文对已有方法深入对比分析,并指出极速学习方法未来的发展方向。 相似文献
105.
Current multimedia extensions provide a mechanism for general-purpose processors to meet the growing performance demand of multimedia applications. However, the computing performance of these extensions is often limited for the design conceptions of the single data stream. This paper presents an architecture called “multi-streaming SIMD” that enables current multimedia extensions to simultaneously manipulate multiple data streams. To efficiently and flexibly realize the proposed architecture, an operation cell is designed by fusing the logic gates and the storage cells together. Multiple operation cells then are connected to compose a register file with the ability of performing SIMD operations called “Multimedia Operation Storage Unit (MOSU)”. Further, many MOSUs are used to compose a multi-streaming SIMD computing engine that can simultaneously manipulate multiple data streams and exploit the subword parallelisms of the elements in each data stream. This paper also designs three instruction modes (global, coupling, and isolated modes) for programmers to dynamically configure the multi-streaming SIMD computing engine at the instruction level to manipulate different amounts of data streams. Simulation results show that when the multi-streaming SIMD architecture has four 4-register MOSUs, it provides a factor of 3.3×–5.5× performance enhancement for traditional MMX extensions on 12 multimedia kernels. 相似文献
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Ya‐Hui Yang Sidney S. Yang Kan‐Sen Chou 《Journal of the Society for Information Display》2010,18(10):745-748
Abstract— This study investigates the effects of subjecting zinc oxide (ZnO) thin films to laser irradiation. The optical, structural, and electrical properties of the as‐deposited and laser‐irradiated films at different laser energies were studied. The transmittances without/with laser irradiation showed a net increase from 85 to 92% (@550 nm) for 250‐nm ZnO films, indicating an improvement in sample crystal linity. In addition, laser treatment decreased the ZnO band gap. Composition structure analysis shows that the crystallinity increased when the laser energy increased. Thin‐film transistors (TFTs) with a ZnO active layer were fabricated. The mobility of as‐deposited ZnO TFT devices (0.19 cm2/V‐sec) increased more than 2.5 times for ZnO of unirradiated laser treatment (0.49 cm2/V‐sec). 相似文献