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61.
Microscale chemistry laboratory is environmentaly friendly and embodies green and sustainable chemistry,since the amount of reagents,waste,energy,and cost can be reduced dramatically.……  相似文献   
62.
63.
In this article we focus on job mobility patterns in Japan and Taiwan, exploring how local institutional settings are linked to patterns of job mobility. Previous studies have distinguished between involuntary and voluntary job mobility. However, more diverse patterns of job mobility may also exist, which are not captured by this dichotomy. In this study we used representative national survey data from Japan and Taiwan and analyzed five types of job turnover: involuntary, positive voluntary, negative voluntary, family related and other. Using event history models we found significant differences between the two societies. First, the effect of higher education on voluntary job mobility was weaker in Japan than in Taiwan. Second, the effect of organizational size on voluntary job mobility was stronger in Japan than in Taiwan. Third, these tendencies were more significant for men than for women. These results suggest that the local institutional filters affect the turnover process.  相似文献   
64.

Background

Older individuals have been shown to present muscle atrophy in conjunction with increased fat fraction in some muscles. The proportion of fat and connective tissue within the skeletal muscle can be estimated from axial B-mode ultrasound images using echo intensity (EI). EI was used to calculate the index of muscle quality. Walking, home-based weight-bearing resistance training, and its combinations are considered simple, easy, and practical exercise interventions for older adults. The purpose of this study was to quantify the effects of walking and walking with home-based resistance training on muscle quality of older individuals.

Methods

Thirty-one participants performed walking training only (W-group; 72?±?5?years) and 33 participants performed walking and home-based resistance training (WR-group; 73?±?6?years). This study was a non-randomized controlled trial with no control group. All participants were instructed to walk 2 or 3 sets per week for 10?weeks (one set: 30-min continuous walking). In addition, the WR-group performed home-based weight-bearing resistance training. EI was measured as a muscle quality index using axial B-mode ultrasound images of the rectus femoris and vastus lateralis of the mid-thigh. We further averaged these parameters to obtain the EI of the quadriceps femoris (QF). Participants further performed five functional tests: sit-ups, supine up, sit-to-stand, 5-m maximal walk, and 6-min walk.

Results

QF EI was significantly decreased in both groups after training (W-group 69.9?±?7.4?a.u. to 61.7?±?7.0?a.u., WR-group 64.0?±?9.5?a.u. to 51.1?±?10.0?a.u.; P?<?0.05), suggesting improved muscle quality. QF EI was further decreased in the WR-group compared with the W-group. The sit-up test in both groups and the sit-to-stand and 5-m maximal walk tests in the W-group were significantly improved after training.

Conclusion

These results suggest that training-induced stimulation is associated with a decrease in EI in some thigh regions. Furthermore, the addition of home-based resistance training to walking would be effective for a greater reduction of EI.
  相似文献   
65.
We investigate the behaviors of subjects who either do or do not adhere to the expected utility theory using the Becker–DeGroot–Marschak (BDM) method. We directly examine the validity of the expected utility theory in order to distinguish subjects into two groups: those who adhere to the expected utility theory (expected utility maximizers) and those who do not adhere to it (non-expected utility maximizers), and then execute the BDM experiment in the both groups. We find that the differences in the stated prices between the expected and non-expected utility maximizers are not significant. This result implies practical usefulness for the BDM method.  相似文献   
66.
This paper examines the relationship between specialization and happiness in marriage in the U.S. and Japan. Our findings, based on the General Social Surveys in the U.S. and Japan, indicate both similarities and differences in the determinants of marital happiness in the two countries. In the U.S., the findings are mixed. Women’s reported marital happiness in the U.S. is more likely to follow the predictions of the bargaining model where their happiness is determined by their own income. Men’s marital happiness in the U.S. follows the predictions of the specialization model; they are happier if their wives are not working or, alternatively, if they are financially dependent on their wives. In Japan, we find support for the specialization model, particularly in the case of women; they are happier if they are specialized in the household and they have a higher household income. Our research highlights how marital quality is affected by the institutional context and the normative environment.  相似文献   
67.
Tactile dots located on operation keys of consumer products such as cellular phones contribute to improving accessibility for older people and people with visual impairment. The Japanese Standards Association (2000) and the International Organization for Standardization (2011) standardized tactile dots. However, reliable data on the appropriate sizes and the shapes was not necessarily available. The purpose of this study is to evaluate influences of the height (0.1, 0.3, 0.55, and 0.75 mm) and the tip radius of curvature (0.1, 0.3, 0.5, 0.7, and 0.9 mm) of tactile dots on the operational performance of cellular phones in younger and older people. Sighted younger and older participants, whose hand was covered by a curtain, operated cellular phones with a tactile dot on its key 5 and without a tactile dot. As the result, both participants performed better at a particular height with larger tip radius of curvature. Furthermore, older participants operated better at high dots like 0.55-0.75 mm. In contrast, younger participants performed better at 0.3 mm and relatively poorly at 0.1 mm and 0.75 mm. Thus, comparatively high tactile dots are useful for improving the accessibility of products for the older and there is an appropriate height range for the younger.  相似文献   
68.

This paper describes a machine learning approach for a manufacturing database. The method is presented in the Nb-Ti superconducting wire domain. A Nb-Ti superconducting wire is produced by iterating the drawing and heat treatment operations. The purpose is to obtain approximate summarization of process data that describes how a production schedule can be improved for better product quality. The method consists of the following steps: First, define a ranking function for a production schedule. Then, generate 'positive' and 'negative' instances for improving a production schedule by comparing a pair of schedules and their ranking values in the database. Using a machine learning technique, called 'ID3', a 'modification patterns' are obtained that generalize the data for better production quality. The final step is to extract approximate information from the induced patterns, which is both desirable for easier understanding by human experts and necessary to avoid being too much influenced by excessive details or disturbances. Two criteria are proposed, correctness and applicability indices, for this approximation.  相似文献   
69.
The multislope ski-rental problem is an extension of the classical ski-rental problem, where the player has several lease options besides the pure rent and buy options. In this problem the hardness of an instance, which is the setting of options, significantly affects the player’s performance. There is an algorithm that for a given instance, computes the best possible strategy. However, the output is given as numerical values and therefore the relational nature between an instance and the best possible performance for it has not been known. In this paper we prove that even for the easiest instance, a competitive ratio smaller than \(e/(e - 1) \approx 1.58\) cannot be achieved. More precisely, a tight lower bound on the best possible performance is obtained in a closed form parametrized by the number of options. Furthermore, we establish a matching upper and lower bound on the competitive ratio each for the 3-option and 4-option problems.  相似文献   
70.
Abstract  This paper examines several foreseeable scenarios about the effects of information technology on the labor market and the process of individual's income attainment. While I do not intend to exclude other factors, I argue that computer literacy and information literacy are two distinct but complimentary factors, and that they will be the two critical issues in determining the productive capacities of workers in the multimedia age. I view information literacy as a firm-specific skill, and argue that it will be the key factor in determining the production function of workers within the firm. Computer literacy is viewed as the endowment of information literacy skills. Workers with higher levels of computer literacy will be at an advantage at the time of labor market entry. Further, such workers are more likely to have higher rates of return on firm's investments in information literacy skills. thereby yielding higher productions. Based on the premise that information technology and labor are complementary components which should reveal an increase in the demand for higher skilled workers, I suggest that income differences are likely to widen along the lines of educational attainment and establishment-size. The "Implications" section (V) of the paper examines several issues for further research in this incipient field of sociology.  相似文献   
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