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1.
The problem of observing the state of a linear finite dimensional system in the presence of unknown disturbance noise is considered. Necessary and sufficient conditions are developed for the existence of a minimal order observer capable of producing an asymptotic estimate of the state of the given system. The approach used leads to a computationally attractive procedure for obtaining an observer having specified eigenvalues.  相似文献   
2.
本文在详细考察了从东晋末至刘宋初期北府兵的主要兵源、晋陵郡域上侨置的无实土侨郡县的受掌控方式后,认为刘宋以后(南朝初期),由于该时期政治格局的变动,北府兵虽然在政治史上没有以其先前的强势面貌出现,但是因其与中央军有着甚为密切的联系,依然拥有左右政局的重要军事地位,其政治上的重大影响依然存在。  相似文献   
3.
Thiolene-based microfluidic devices have been coupled with surface plasmon resonance imaging (SPRI) to provide an integrated platform to study interfacial interactions in both aqueous and organic solutions. In this work, we develop a photolithographic method that interfaces commercially available thiolene resin to gold and glass substrates to generate microfluidic channels with excellent adhesion that leave the underlying sensor surface free from contamination and readily available for surface modification through self-assembly. These devices can sustain high flow rates and have excellent solvent compatibility even with several organic solvents. To demonstrate the versatility of these devices, we have conducted nanomolar detection of streptavidin-biotin interactions using in situ SPRI.  相似文献   
4.
In 1972 a longitudinal study was launched in one of the largest department store chains in Japan. The purpose of this study was to investigate the managerial career development of the newly hired college graduates. The research design required repeated monitoring of a newcomer's progress within the organization at seven different points in time over a three-year period. The study investigated basic questions concerning the process of managerial career development: (1) Why do some people achieve a higher level of management progress during the early period of their organizational career, while others do not? (2) What are the important indicators of management development during the formative years in business? (3) How accurately can development in management be predicted? (4) What are the organizational and personal consequences of managerial development? Over the three-year period of this study data were collected on 80 newly hired college graduates. Two models that have been used to understand the process of early management development in the United States were tested. Results were compatible with these models. Performance at the end of three years was found to be significantly related to both initially assessed potential (assessment model) and developed working relationships (vertical exchange model). Other professional and organizational outcomes were significantly related to developed working relationships. The implications of this cultural generality are discussed.  相似文献   
5.
The purpose of the study presented in this paper is to examine uses of evidence inuniversity students' writing of scientific argument. The study was conducted in anintroductory level oceanography course in a large public university. In this course students draw on large-scale geological data sets provided by an interactive CD-ROM,`Our Dynamic Planet' (Prothero 1995), to write a scientific technical paper. We examined the uses of evidence in two ways. First, we conducted interviews with undergraduate oceanography students n = 9, non-oceanography undergraduate students n = 8 , and course instructors n = 4 to assess the differences in interpretation of uses of scientific evidence for high ranked and low ranked student papers from a previous academic year. Second, we applied our proposed argumentation analysis to student writing to examine the formulation of evidence in these high and low ranked papers. We draw on these findings to discuss ways of teaching students the construction of argument in scientific writing.  相似文献   
6.
The issue of international student mobility has had a profound effect on policy decision-making in the higher education system of essentially every country; however, the statistical data on this subject are insufficient, especially for graduate students. The purposes of this study are to substantiate the state of international mobility among talented graduate students in the sciences and engineering who will publish scholarly research in their future career and to present the mechanism of their moves between institutions. This paper quantitatively analyzes the trajectories of more than 7,000 scientists and engineers beginning at graduate school, obtained from the biographical notes attached to journal articles for authors in the fields of computer vision, robotics, and electron devices. The results suggest that mobility in various engineering fields at world-class research universities is subject to varied pull and push factors. In the fields of computer vision and robotics, a high world university ranking is a significant pull factor in the global mobility of graduate students, which may promote a US-dominated stratification between institutions of higher education, since the institutions at the top end of these rankings are generally in the United States. In contrast, in the field of electron devices, employment for highly skilled workers in domestic industries seems to act as an alternative pull factor for talented graduate students. This article also sheds light on the status of the universities that underpin first-tier research universities by providing undergraduate students to them, an important role that tends to be concealed in the world university rankings. Furthermore, this article suggests the existence of complementary relationships between the globally top-ranked research universities and the exporting top national research universities in various countries, a relationship that is key to the shape of the current global higher education system.  相似文献   
7.
We examined the effect of a combination of astaxanthin (AX) supplementation, repeated heat stress, and intermittent reloading (IR) on satellite cells in unloaded rat soleus muscles. Forty-nine male Wistar rats (8-week-old) were divided into control, hind-limb unweighting (HU), IR during HU, IR with AX supplementation, IR with repeated heat stress (41.0–41.5 °C for 30 min), and IR with AX supplementation and repeated heat stress groups. After the experimental period, the antigravitational soleus muscle was analyzed using an immunohistochemical technique. Our results revealed that the combination of dietary AX supplementation and heat stress resulted in protection against disuse muscle atrophy in the soleus muscle. This protective effect may be partially due to a higher satellite cell number in the atrophied soleus muscle in the IR/AX/heat stress group compared with the numbers found in the other groups. We concluded that the combination treatment with dietary AX supplementation and repeated heat stress attenuates soleus muscle atrophy, in part by increasing the number of satellite cells.  相似文献   
8.
In the application of 2-D adaptive filters, a large amount of data must be processed and real-time processing is often required. In this paper, a new parallel-form realization of 2-D adaptive separable-denominator state-space filters suitable for high-speed processing is proposed. First, the 2-D local state-space model suitable for parallel processing is introduced. Next, the adaptive algorithm for this model is developed. This algorithm is based on the delayed least mean square (DLMS) method. In addition, the computation time required for the update of the coefficients is investigated. Finally, the proposed technique is applied to the design of 2-D digital filters in the spatial domain.  相似文献   
9.
An analytical technique is developed for designing multidimensional (M-D) separable-denominator recursive digital filters that meet, simultaneously, magnitude and phase specifications. A cubic symmetry that exists in the M-D frequency response is incorporated into the M-D filter structure. The denominator and the numerator of an M-D transfer function are designed separately. The former is used to approximate constant group delays and the latter is used to adjust an overall magnitude response. The filter is analytically designed by solving linear equations only. This serves to reduce the amount of calculations drastically. The stability of the resulting filter is always guaranteed. Finally, two examples are given to illustrate the utility of the proposed technique.  相似文献   
10.
This study examined ageing and free-living daily physical activity effects on salivary human beta-defensin 2 (hBD2). A total of 168 healthy elderly and 26 healthy young volunteers underwent saliva sampling. Free-living step count, energy expenditure and activity durations at specific intensity levels (inactive, light, moderate and vigorous) were evaluated. The results show significantly lower salivary hBD2 secretion rates for elderly than for young participants (P < 0.05). Data from elderly participants were stratified by steps per day using quartiles (Q1–Q4) for distribution. Elderly in quartiles respectively showed step counts of 3145 ± 129 in Q1, 5294 ± 83 in Q2, 7001 ± 86 in Q3 and 10,236 ± 416 steps · day?1 in Q4. In elderly participants, significant differences were found in the mean step count, energy expenditure and activity duration with increasing pedometer-determined activity quartiles. hBD2 secretion rates were significantly higher for Q2, Q3 and Q4 than for Q1 (P < 0.05). Elderly participants in Q3 had the highest hBD2 secretion. In conclusion, these results suggest that moderate physical activity in daily living improves age-related impairment of oral immune function mediated by hBD2. For oral immune function enhancement and for prevention of upper respiratory tract infections in elderly people, we recommend accumulation of more than 7000 steps · day?1.  相似文献   
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