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1.
Tachibana K Yashiro K Miyazaki J Ikegami Y Higuchi M 《Sports biomechanics / International Society of Biomechanics in Sports》2007,6(1):44-58
Although it is clear that rowers have a large muscle mass, their distribution of muscle mass and which of the main motions in rowing mediates muscle hypertrophy in each body part are unclear. We examine the relationships between partial motion power in rowing and muscle cross-sectional area of the thigh, lower back, and upper arms. Sixty young rowers (39 males and 21 females) participated in the study. Joint positions and forces were measured by video cameras and rowing ergometer software, respectively. One-dimensional motion analysis was performed to calculate the power of leg drive, trunk swing, and arm pull motions. Muscle cross-sectional areas were measured using magnetic resonance imaging. Multiple regression analyses were carried out to determine the association of different muscle cross-sectional areas with partial motion power. The anterior thigh best explained the power demonstrated by leg drive (r2 = 0.508), the posterior thigh and lower back combined best explained the power demonstrated by the trunk swing (r2 = 0.493), and the elbow extensors best explained the power demonstrated by the arm pull (r2 = 0.195). Other correlations, such as arm muscles with leg drive power (r2 = 0.424) and anterior thigh with trunk swing power (r2 = 0.33 5), were also significant. All muscle cross-sectional areas were associated with rowing performance either through the production of power or by transmitting work. The results imply that rowing motion requires a well-balanced distribution of muscle mass throughout the body. 相似文献
2.
Temporal variation of dynamical modal properties of a base-isolated building is investigated using earthquake records in the building. A batch processing least-squares estimation method is applied to segment-wise time-series data. To construct an input-output system, an auto-regressive model with exogenous input （ARX） of second-order including a forgetting coefficient as a weighting coefficient is used for the estimation of modal parameters. The fundamental and second natural frequencies and the damping ratios of the fundamental and second natural modes of the base-isolated building are identified in the time domain. The identified results are consistent with the results obtained from the micro-tremor vibration data, forced-vibration test data and earthquake records in the present base-isolated building in the case of taking into account the amplitude-dependency of the iso- lators and viscous dampers. It is finally pointed out that several factors, e.g., amplitude dependency of the isolator and damper system and special characteristics of the series-type viscous damper system, may be related complicatedly with the temporal variation in modal properties of the above-mentioned system. 相似文献
3.
Mitsuru Sunada 《Journal of Cultural Economics》2012,36(3):179-206
This study assesses the 1951 Toho?CSubaru antitrust merger case in the Japanese movie theater market. Using information regarding the location of theaters in the Tokyo metropolitan area, I examined the relationship between the number of attendees and the structure of the local market competition: a regression equation relating to the number of attendees and the local market structure was derived from a model of product differentiation, which incorporated the features of a movie theater market. The results revealed that nearby rival theaters had negative effects on other theaters?? attendance numbers, and these effects did not dissipate even where there was 10?km between each theater. Based on empirical results, it appears that the Tokyo High Court and the competition agency defined the geographic movie theater market as being smaller than it actually was. The results of this study suggest that the application of econometric analysis, combining geographic information, is useful in merger reviews of retail industries, such as movie theaters. 相似文献
4.
In this paper,the network reliability of an actual digital instrument and control system (DICS) network is analyzed by using GO-FLOW methodology (GFM).The evaluations of common-cause failure (CCF) and uncertainty are incorporated.Three significant CCF groups (real time servers,gateways,reactor protection system) and three typical time intervals (10 min,1 h,and 24 h) are selected in the analysis.It is concluded that the network contribution of CCF accounts for over 68% of the system failure probability.The result indicates that GFM is suitable for the network reliability analysis. 相似文献
5.
Kihoon Jang Yo Tanaka Jun Wakabayashi Reina Ishii Kae Sato Kazuma Mawatari Mats Nilsson Takehiko Kitamori 《Biomicrofluidics》2012,6(4)
Demand for analysis of rare cells such as circulating tumor cells in blood at the single molecule level has recently grown. For this purpose, several cell separation methods based on antibody-coated micropillars have been developed (e.g., Nagrath et al., Nature 450, 1235–1239 (2007)). However, it is difficult to ensure capture of targeted cells by these methods because capture depends on the probability of cell-micropillar collisions. We developed a new structure that actively exploits cellular flexibility for more efficient capture of a small number of cells in a target area. The depth of the sandwiching channel was slightly smaller than the diameter of the cells to ensure contact with the channel wall. For cell selection, we used anti-epithelial cell adhesion molecule antibodies, which specifically bind epithelial cells. First, we demonstrated cell capture with human promyelocytic leukemia (HL-60) cells, which are relatively homogeneous in size; in situ single molecule analysis was verified by our rolling circle amplification (RCA) method. Then, we used breast cancer cells (SK-BR-3) in blood, and demonstrated selective capture and cancer marker (HER2) detection by RCA. Cell capture by antibody-coated microchannels was greater than with negative control cells (RPMI-1788 lymphocytes) and non-coated microchannels. This system can be used to analyze small numbers of target cells in large quantities of mixed samples. 相似文献
6.
Bilateral leg extension power and fat-free mass in young oarsmen 总被引：1，自引：0，他引：1
We evaluated the impact of bilateral leg extension power and fat-free mass on 2000 m rowing ergometer performance in 332 young oarsmen (age 21+/-2 years, height 1.76+/-0.05 m, body mass 62+/-6 kg; mean+/-s). The 2000 m rowing performance time was correlated with height (1.62-1.93 m; R2=0.23, P<0.001), body mass (53-95 kg; R2=0.53, P<0.001), fat-free mass (47-82 kg; R2=0.58, P<0.001) and bilateral leg extension power (1202-3302 W; R2=0.38, P<0.001). Multiple regression analysis selected fat-free mass and bilateral leg extension power as regressor variables. Fat-free mass explained 58% of the variability in rowing performance and the inclusion of bilateral leg extension power improved the power of prediction by 5%. The results suggest that rowing involves almost every muscle in the body and that bilateral leg extension power is very important during this activity. 相似文献
7.
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
8.
This paper provides a new point of view regarding the knowledge management of new product development (NPD), a high-tech field requiring the merging and integration of different technologies. As a case study, we examine the dynamism of the knowledge creation process in NPD at Nippon Telegraph and Telephone Corporation (hereafter referred to as NTT), a traditional Japanese telecommunication company, as it merges and integrates the different elements of broadband network technology, network operation technology, and multimedia processing technology etc., and we analyze the NPD processes of NTT. In a short period of time, a strategic team at NTT, consisting mainly of informal cross-functional middle managers transcending NTT's business divisions, formed strategic communities inside and outside the company, and then formed a network that transcended the strategic communities' boundaries. The synthesizing capability of the leadership-based strategic communities comprising community leaders inside the networked strategic communities enabled NTT to build new business models aimed at customers and achieve successful NPD ahead of other competitors. 相似文献
9.
Mitsuru Saito 《Research quarterly for exercise and sport》2013,84(4):323-329
Abstract The present study was undertaken to reveal the relationships among velocity (V), stroke rate (S), and distance per stroke (d/s) in the breaststroke, and to determine whether the swim velocity of the breaststroke is increased by an increased stroke rate induced by breaststroke training. A total of 168 ordinary high school students were engaged for the present study. In order to measure the swimming time and strokes during breaststroke at maximum effort for the 50m distance, a videotape recorder (VTR) with video timer system was employed, and the recordings were used in analyses. The S and d/s were calculated for each subject. It was found in this study that V is significantly related to d/s before and after training, but has no relation to S. From these results, it is suggested that improvement of velocity during breaststroke depends upon an increase of d/s, rather than S. This is considered to be an index of efficiency or technique in the breaststroke. 相似文献
10.
Danushka Bollegala Tomokazu Goto Nguyen Tuan Duc Mitsuru Ishizuka 《Information processing & management》2013
Measuring the similarity between the semantic relations that exist between words is an important step in numerous tasks in natural language processing such as answering word analogy questions, classifying compound nouns, and word sense disambiguation. Given two word pairs (A, B) and (C, D), we propose a method to measure the relational similarity between the semantic relations that exist between the two words in each word pair. Typically, a high degree of relational similarity can be observed between proportional analogies (i.e. analogies that exist among the four words, A is to B such as C is to D). We describe eight different types of relational symmetries that are frequently observed in proportional analogies and use those symmetries to robustly and accurately estimate the relational similarity between two given word pairs. We use automatically extracted lexical-syntactic patterns to represent the semantic relations that exist between two words and then match those patterns in Web search engine snippets to find candidate words that form proportional analogies with the original word pair. We define eight types of relational symmetries for proportional analogies and use those as features in a supervised learning approach. We evaluate the proposed method using the Scholastic Aptitude Test (SAT) word analogy benchmark dataset. Our experimental results show that the proposed method can accurately measure relational similarity between word pairs by exploiting the symmetries that exist in proportional analogies. The proposed method achieves an SAT score of 49.2% on the benchmark dataset, which is comparable to the best results reported on this dataset. 相似文献