• 산업경영시스템학회지
• /
• 제19권37호
• /
• pp.187-194
• /
• 1996

Firms pay cash dividends to reduce the agency costs, and then insider stock ownership affects the dicision of dividend payout ratio. In this study, it is tested that firm's insider stock ownership affects the decision of dividend payout ratio, but the relation between dividend payout ratio and insider stock ownership is nonmonostic. The empirical evidence shows that at low levels of insider stock ownership, increase in the percentage of stock held by insiders decreases dividend payout ratio, but beyond the point of entrenchment increase in the percentage of stock held by insiders increases dividend payout ratio. Thus, the dividend payout ratio and the percentage of stock held by insiders are in a parabolic relation. This implies that there may be a optimal insider stock ownership In lead to the minimun dividend payout ratio.

• 한국농공학회논문집
• /
• 제48권5호
• /
• pp.51-60
• /
• 2006

In order to examine the heat transfer characteristic of a soil warming system and effects of soil warming on the greenhouse heating load, control experiments were performed in two greenhouses covered with double polyethylene film. One treated the soil warming with an electric heat wire and the other treated a control. Inside and outside air temperature, soil temperature and heat flux, and heating energy consumption were measured under the set point of heating temperature of $5,\;10,\;15,\;and\;20^{\circ}C$, respectively. Soil temperatures in a soil warming treatment were observed $4.1\;to\;4.9^{\circ}C$ higher than a control. Heating energy consumptions decreased by 14.6 to 30.8% in a soil warming treatment. As the set point of heating temperature became lower, the rate of decrease in the heating energy consumptions increased. The percentage of soil heat flux in total heating load was -49.4 to 24.4% and as the set point of heating temperature became higher, the percentage increased. When the set point of heating temperature was low in a soil warming treatment, the soil heat flux load was minus value and it had an effect on reducing the heating load. Soil heat flux loads showed in proportion to the air temperature difference between the inside and outside of greenhouse but they showed big difference according to the soil warming treatment. So new model for estimation of the soil heat flux load should be introduced. Convective heat transfer coefficients were in proportion to the 1/3 power of temperature difference between the soil surface and the inside air. They were $3.41\;to\;12.42\;W/m^{2}^{\circ}C$ in their temperature difference of $0\;to\;10^{\circ}C$. Radiative heat loss from soil surface in greenhouse was about 66 to 130% of total heating load. To cut the radiation loss by the use of thermal curtains must be able to contribute for the energy saving in greenhouse.

• Korean Journal of Acupuncture
• /
• 제26권4호
• /
• pp.145-156
• /
• 2009

Objective : To increase the safety of moxibustion by understanding moxibustion-prohibited points' distinguishing features through literary inquiry. Method : We searched for moxibustion-prohibited points in Traditional Oriental Medical literature. Results : 1. Upon the advancement of moxibustion technique, the numbers of moxibustion-prohibited points increased. 2. Both Foot Meridians and Hand Meridians have similar percentage of moxibustion-prohibited points. Both Yin Meridians and Yang Meridians have similar percentage of moxibustion-prohibited points. 3. The face has the highest moxibustion-prohibited points ratio. The Back has the lowest moxibustion-prohibited points ratio. 4. We research 80 moxibustion-prohibited points and find 31 moxibustion-prohibitive reasons. A key reasons is that heating effect of moxibustion damages tissues, organs and meridian functions. There are also cases where the moxibustion-prohibited points can be designated upon the patients condition Conclusions : We could learn the distinguishing characteristics of moxibustion-prohibited points from this study. These results suggest that the treatment of moxibustion is more useful and safe.

• 경제분석
• /
• 제25권2호
• /
• pp.96-131
• /
• 2019

본 연구에서는 OECD 선진 21개국(우리나라 포함)의 연령층별 실업률 및 노동시장 제도 및 정책 변수를 이용하여, 청년실업 이력현상(hysteresis)의 존재 가능성과 그 크기를 시계열 및 국가패널 자료로 분석하였다. 크기 추정에 있어서는 병역의무 이행 등 우리나라 특수상황, 여성 경력단절 효과 등을 고려하여, 분석대상을 20~29세의 남성 청년층으로 한정하였다. 또한, 노동시장 제도 및 정책 변수로는 국가간 비교가 가능한 OECD자료의 8가지 변수를 감안하였는데, 우리나라는 고용보호법제화 지수를 제외한 여타 제도 및 정책들은 낮은 수준이었다. 시계열자료의 단위근 분석결과, 우리나라를 제외한 대부분 국가에서 청년실업률(15~24세)에 단위근이 존재하여 평균회귀 성향보다 전(前)기 의존성이 높았다. 우리나라는 15~29세, 20~29세 청년실업률에서 단위근이 존재하는 것으로 나타나 이력현상이 존재할 수 있음을 확인할 수 있었다. 이력현상의 크기를 패널분석으로 추정한 결과, 직업훈련·취업지원 등 적극적 노동정책지출에 미온적이거나 고용보호법제가 엄격한 국가일수록, 청년기(20~29세)에 높은 실업률을 경험한 세대가 이후 연령대에서도 다른 세대에 비해 더 높은 실업률을 겪는 이력현상이 더 크게 나타나 선행연구의 결과를 재차 확인할 수 있었다. 따라서, 청년실업의 이력효과 완화를 위해서는 내실있는 직무 및 직업교육과 취업지원 등 효과적인 적극적 노동정책지출을 확대해 나가고, 고용보호법제내(內)에 청년고용을 제약하는 요소는 없는지 살펴보는 것이 바람직해 보인다.

• 생태와환경
• /
• 제38권spc호
• /
• pp.67-75
• /
• 2005

The objectives of this study were to understand the runoff characteristics of the non-point sources originating from impervious surfaces and to assess their effect on the aquatic environment in the urban areas. The concentration of pollutants (SS, BOD, COD and T-P) except for T-N showed the highest value in runoff from road, and event mean concentration (EMC) also showed high value from road. The pollutants discharged from road showed a higher concentration in the beginning stage (0 ${\sim}$ 30%) of progressive percentage of rainfall. The contribution percentages of non-point sources by load were 44.9% for SS, 11.2% for BOD, 21.4% for COD, 11.4% for T-N and 8.1% for T-P in the total load of pollutant discharged through sewer. From our results, the road was a significant potential source that deteriorated water quality of the streams and lakes in the vicinity of the urban area during the rain period. Therefore, counter plan is required to reduce pollutant concentration on the road from non-point sources in the urban area. Also, since pollutant concentration in the beginning stage of rainfall was quite high, road cleaning seems to be one of the very useful methods to prevent inflowing of pollutants to the aquatic environment.

• 드라이브 ㆍ 컨트롤
• /
• 제21권2호
• /
• pp.65-71
• /
• 2024

In this study, we suggested a key-point detection method for robot harvesting of oriental melon. Our suggested method could be used to detect the detachment part and major composition of oriental melon. We defined four points (harvesting point, calyx, center, bottom) based on tomato with characteristics similar to those of oriental melon. The evaluation of estimated key-points was conducted by pixel error and PDK (percentage of detected key-point) index. Results showed that the average pixel error was 18.26 ± 16.62 for the x coordinate and 17.74 ± 18.07 for the y coordinate. Considering the resolution of raw images, these pixel errors were not expected to have a serious impact. The PDK score was found to be 89.5% PDK@0.5 on average. It was possible to estimate oriental melon specific key-point. As a result of this research, we believe that the proposed method can contribute to the application of harvesting robot system.

• 한국소음진동공학회논문집
• /
• 제17권5호
• /
• pp.437-447
• /
• 2007

A series of research to seek for the relationship between subjective responses and noise level for transportation noise have been proceeded, and their results showed similar for some cases and different for some other cases as well, which is considered due to the various conditions such as the way of survey, different scale applied, and country etc. This study aimed to analyze the relationship between sound level and subjective response for the different kinds of transportation noise. The noises recorded in real situation were played to thirty subjects with fourty nine adjectives. The percentage of people annoyed(% PA) and the percentage of people highly annoyed(% HA) were calculated from the subjective results and compared how many percent of people are annoyed and highly annoyed for the same sound level. As a result of calculating the average, the aircraft noise was highest and the white noise lowest. The relationship between window TL and average point was well correlated except the aircraft noise which was scattered because of high sound level at specific frequency and low TL at corresponding frequency. This means that appropriate rating method for airborne sound transmission should be sought for to evaluate outdoor noise which has different frequency characteristics. The Boltzmann equation for % PA and % HA was applied to predict the sound level corresponding to the percentage. It is concluded that the aircraft noise and road traffic noise have almost same response and the railway noise was same with white noise, used for the reference noise, annoyed lower than other noises about by 3 dB.

• 전기학회논문지
• /
• 제63권6호
• /
• pp.855-859
• /
• 2014

Quality criteria for interaction between a pantograph and overhead contact wire is a most important requirement to assess of the performance for the current collection system. Interaction performance between pantograph and catenary system is subject to approval by the infrastructure manager when a new design and contraction of overhead contact line and pantograph are installed. Among the various performance, percentage of arcing at maximum line speed is a simple test method compared with contact force of pantograph due to direct sensing of pantagraph, calibrations, installations of train, and etc. On the other hand, percentage of arcing is need to reliable arcing detector and general requirements with accordance with EN 50317. In this paper, percentage of arcing are investigated on the function of duration of arc and proposed which is satiable of percentage of arcing. As a results, we proposed which duration of arcs are unsuitable from infrastructures point of view as performance testing for quality of current collection.

• 대한가정학회지
• /
• 제37권8호
• /
• pp.55-72
• /
• 1999

The purpose of this study is to identify the levels of informationized life of individual, consumers knowledge and attitudes to informationized society, and the recognition of consumer problems in informationized society, and to investigate the related variables. Data were collected from 693.consumers living in Seoul using the constructed questionnaires by the authors. Frequency, Percentage and Multiple Regression Analysis were applied for the analysis. The level of informationized life of consumers was lower than the mid-point of the scale, the level of the consumers knowledge about informationized society was sightly higher than mid-point of the scale, and the consumer attitudes to informationized society appeared to be positive. The level of the recognition of consumer problems in informationized society was higher than the mid-point of the scale,and was influenced by job, age of consumers, and the level of consumers knowledge about informationized society.

• 한국정밀공학회:학술대회논문집
• /
• 한국정밀공학회 2001년도 춘계학술대회 논문집
• /
• pp.53-56
• /
• 2001

Reverse engineering has been widely used for the shape reconstruction of an object without CAD data and it includes some steps such as scanning of a clay or wood model, and generating some manufacturing data in an STL file. A new approach to remove point data with Delaunay triangulation is introduced to deal with the size problems of STL file and the difficulties in the operation of RP process. This approach can be used to reduce a number of measuring data from laser scanner within a specified tolerance, thus it can avoid the time for handing point data during modeling process and the time for verifying and slicing STL model during RP process. Developed software enables the user to specify the criteria for the selection of group of triangles either by the angle between triangles or the percentage of triangles reduced, and thus RP models with accuracy will be helpful to automated process.