• Journal of Sericultural and Entomological Science
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• v.10
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• pp.59-62
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• 1969

It is very important physiological and economical problems to hatching within a day by increasing hatching-ratio of silkworm eggs in sericulture, and modified dark incubating method was experimented in Japan. The author studied on the economical problems of that rather than physiological study. Hatching was induced and accelerated by illumination before hatching 5 days which incubated in the dark room after eye spot pigmented eggs emerged 10-20 percentage. It was increased by 80-90％ in hatching-ratio, but the hatching was delayed a day. In autumn silkworm, newly hatched silkworms were hatched silkworms were hatched in the dark room because of high temperature period tough modified dark incubation was passed only 4 days. The author wonder which is more effective between effect of increasing the hatching-ratio and the health of silkworms.

• 한국전산유체공학회:학술대회논문집
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• 2008.03b
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• pp.284-287
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• 2008

Flow over a sphere under forced oscillation at Re=300 is simulated for various frequency ratios which are defined as excitation frequency over natural frequency of stationary sphere. The results of oscillating sphere are compared with those of stationary sphere and an oscillating cylinder. Detailed vortical structures, hydrodynamic forces and frequencies of the wake are prescribed as a function of frequency ratio. For oscillating sphere, planar symmetry of the wake is kept and two nearly symmetric hair pin vortices are induced by oscillation for one period of oscillation when the frequency ratio is bigger than 0.5. Modulation phenomenon which can be found in an oscillating cylinder were not seen for an oscillating sphere.

• The Journal of Korean Medicine
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• v.22 no.4
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• pp.114-120
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• 2001

Objectives : Man adapts himself to nature, so accordingly as he grows up, changes of body composition appear. This study measured the changes of body compositions on the ground of Sasang constitution and seasons Methods : 253 middle school students who live in Busan were studied from the 20th of March, 1999 to the 20th of March, 2001. We measured height and body compositions with Inbody 3.0, six times during that period. Results : According as they grew up, total body water, muscle area, body weight, BMI (Body Mass Index), BMR (Basal Metabolic Rate), ACM (Arm Muscle Circumference), and BCM (Body Cell Mass) increased, but fat body weight ratio decreased. From March to June, total body water, muscle area, height, ACM, and BCM increased. From September to December fat body weight, fat body weight ratio, waist hip ratio increased as compared with other seasons. Height of Soyangin and BMI of both Soyangin and Taeumin increased more than those of other groups, with statistical significance Conclusions : The growth of man is adapting oneself to changes of nature, and it corresponds to the theory of (correspondence between man and universe).

• Journal of Distribution Science
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• v.12 no.3
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• pp.33-41
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• 2014

Purpose - The purpose of this study was to predict the selection of independent auditors in the companies listed on the Tehran Stock Exchange (TSE) using a combination of PSO algorithm and CART. This study involves applied research. Design, approach and methodology - The population consisted of all the companies listed on TSE during the period 2005-2010, and the sample included 576 data specimens from 95 companies during six consecutive years. The independent variables in the study were the financial ratios of the sample companies, which were analyzed using two data mining techniques, namely, PSO algorithm and CART. Results - The results of this study showed that among the analyzed variables, total assets, current assets, audit fee, working capital, current ratio, debt ratio, solvency ratio, turnover, and capital were predictors of independent auditor selection. Conclusion - The current study is practically the first to focus on this topic in the specific context of Iran. In this regard, the study may be valuable for application in developing countries.

• Steel and Composite Structures
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• v.2 no.6
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• pp.461-474
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• 2002

This paper presents the experimental and theoretical results of SUS 304 stainless tubes with different diameter-to-thickness ratio (D/t ratio) subjected to pure bending creep. Pure bending creep occurs when a circular tube is bent to a desired moment and held at that moment for a period of time. It was found that the magnitudes of the creep curvature and ovalization of tube cross-section increase faster with a higher hold moment than that with a lower one. Due to continuously increasing curvature, the circular tubes eventually buckle. Finally, a theoretical form was proposed in this study so that it can be used to describe the relationship between the creep curvature and time. Theoretical simulations are compared with the experimental test data, showing that good agreement between the experimental and theoretical results has been achieved.

• Atmosphere
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• v.16 no.2
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• pp.55-65
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• 2006

The characteristics of Depth-Area-Duration (DAD) for 50 storms over the Geumgang river basin have been analysed in terms of various storm causes using the precipitation data during the period from 1984 to 2003. Results show that the ratio of the precipitation depth to duration, and the ratio of decrease in the precipitation depth to area are the largest in the case of the tropical cyclone. Storm maximization ratios are in the range 1.03 to 2.66 for the 50 selected heavy precipitation cases over Geumgang river basin, with the largest value for the tropical cyclone case, suggesting that the tropical cyclone could cause heavier precipitation than the other storms. In addition, the 24-hour probable maximum precipitation for the Geumgang river basin is estimated to be about 745 mm in the maximum precipitation area.

• Proceedings of the Korean Geotechical Society Conference
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• 2009.09a
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• pp.511-518
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• 2009

In this study, by the consideration of in situ curing conditions, cemented sand with cement ratio less than 20% is prepared by air dry condition and then wetted. A series of unconfined compression tests are carried out to evaluate the effect of wetting on the strength of cemented soils. Strength of air dry cured specimen drops to maximum 30% after wetting at the end of curing period when cement ratio is low. However, regardless of cement ratio, strength of repetitively wetted specimens during curing increases as the number of wetting increases. The results of this study can predict the strength variation of cemented sand depending on wetting conditions in the field, which can guarantee the safety of geotechnical structures such as dam.

• KIEAE Journal
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• v.6 no.2
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• pp.35-42
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• 2006

This study is to investigate the possibility of a quantitative analysis on sunshine right in apartment houses with a new evaluation index of shading area ratio(SAR) which represents seasonal average value of shaded portion of a window during definite period. SAR values of each apartment houses in a prototype building was calculated depending on apartment building arrangement types and orientations. Since the new method proposed in this research is able to measure the sunshine possibility of the each house in detail, which is more precise and descriptive than the existing method of sunshine judgment standard based on the sunshine hours only at winter solstice, it can be appropriately utilized as a highly qualified sunshine right judgment measures in apartment buildings.

• International Journal of Air-Conditioning and Refrigeration
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• v.16 no.4
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• pp.109-116
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• 2008

Ground temperature restoration characteristics are the crucial factors to evaluate whether a ground source heat pump system can keep long time steady operation. They are mainly dependent on soil thermal properties, layout of pile group, operation/shutoff ratio, cooling/heating load, thermal imbalance ratio and so on. On the one hand, several types of vertical pile foundation heat exchangers are intercompared to determine the most efficient one by performance test and numerical method. On the other hand, according to the layout of pile group of a practical engineering and running conditions of a GSHP system in Shanghai, the temperature distribution during a period of five years is numerically studied. The numerical results are analyzed and are used to provide some guidance for the design of large-scale GSHP system.

• Journal of the Korean Society of Propulsion Engineers
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• v.24 no.4
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• pp.66-72
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• 2020

In this report, the post-curing and chemical aging ratio of propellants are described according to several aluminum contents. Under the same curing conditions, it was confirmed that the post-curing period of propellant having the aluminum content of 18 wt% was longer than the propellant having the 2 wt% of aluminum. On the other hand, in the chemical aging ratio analysis including post-curing, the propellant having the 18 wt% of aluminum was confirmed that the chemical aging proceeds slowly compared to the propellant having an aluminum content of 2 wt%.