• Korean Journal of Organic Agriculture
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• 제29권1호
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• pp.75-84
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• 2021

Shrub growth and fruit characteristics and working time of 'Duke' blueberry by shrub distance were investigated. Overapping rate of blueberry crown was 109% in 0.6 m shrub distance, 37% in 1.2 m shrub distance, and -88% in 2.4 m shrub distance, respectively. The number of main stem tended to increase as the shrub spacing widened. The other fruit characteristics, except for the fruit weight, did not show any significantly different according to the shrub distance. The yield per 10 a was 2,097 kg for 0.6 m shrub distance, 1,303 kg for 1.2 m shrub distance, and 710.7 kg for 2.4 m shrub distance in 2019, respectively. Total working time was 154 hr for 0.6 m shrub distance, 114 hr for 1.2 m shrub distance, and 74 hr for 2.4 m shrub distance. Therefore, the blueberry shrub distance was judged to be appropriate about 1.2 m in the long-termly. However, in order to increase yield early and income, the shrub can maintain 0.6 m distance during young shrub, it can managed flexibly to 1.2 m distance when it becomes a mature shrub.

• Journal of the Korean Society for Railway
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• 제7권4호
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• pp.350-355
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• 2004

Because the wage of railway crews is based on the duty hour rather than the working hour, most researches have focused on the balance of duty hour for the crews. In this paper, the structure of duty hour and its relationship to the crew wage are analyzed and some issues are identified. The duty hour consists of several different jobs which are weighed equally in calculating the crew's wage. Also, the difference between the working hour and duty hour is inconsistent with the train routes; i.e., the difference of a long distance train is larger than that of a small or medium distance train. To solve the problems, possible ways to link the duty hour to the wage better are proposed and exemplified

• Proceedings of the ESK Conference
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• 대한인간공학회 1995년도 춘계학술대회논문집
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• pp.155-164
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• 1995

For efficient operation, vital hand controls must be easily controlled by the operator from his normal working position. The primary working area based on operator's working comfort was developed to serve as a design guideline tothe control panel layout. Ten male subjects participated in the experiment in which working comfort was measured for two controls of a lever type control and a knob type control with respect to the frontal and sagittal distances from the body center and the slope of a workplace. The response surface methodolgy using a central composite design was employed to develop a prediction model for perceived working comfort of each control. Both controls have a similar pattern of comfortable working area, but the lever type control has slightly broader working area. The concept of the proposed working area is a significant extension to the conventional working area such as Farley's or Squires' curves. It is shown that the distance toa control device and the slope have a quadratic effect to working comfort. It is noticeable that comfortable working area exists outside the conventional working area. The result of the response surface analysis also indicated that a little slope of about 15 .deg. for a control panel improves working comfort.

• Journal of the Korean Society of Safety
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• 제15권1호
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• pp.72-79
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• 2000

In recent, occupational diseases in harmful working places become a social issue. It is the well-known fact that a respiration in polluted working places exert a serious effect on health of workers. Accordingly, the cutting off contaminants air originally is the best way to improve working environments. In these cases, ventilation systems should be essentially installed to dilute or exhaust the contaminated indoor air. In this study, we investigated the characteristics of ventilation system of the noxious gas in working indoor places with natural ventilation by using COMET. The numerical simulations were carried out the natural ventilation with two phase(air, dust). For turbulent flow, Reynolds stresses were closed by the standard $\kappa$-$\varepsilon$ model. The results are as follows ; 1) In the natural exhaust in the working place, the flows of the central region have a more rapid velocity vector than the right and left one. 2) Numerical results show that the distribution of contaminants concentration have greater influence on convection than the case of diffusion by government of velocity vectors. 3) To observe the velocity variation with distance, three location of distance are considered. As results, it shows that the velocity are 0.075(m/s) at y=5(m), 10(m) and mean concentration are raised 10.6% at y=5(m), 10(m). 4) We have presented the useful data for the adequate counterplan in the harmful working places by carrying out the various investigation of the natural ventilation.

• Journal of the Semiconductor & Display Technology
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• 제9권1호
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• pp.17-21
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• 2010

Currently miniaturized electron-optical columns find their way into electron beam lithography systems. For better lithography process, it is required to make smaller spot size and longer working distance. But, the micro-columns of the multi-beam lithography system suffer from chromatic and spherical aberration, even when the electron beam is exactly on the symmetric axis of the micro-column. The off-axis error of the electron emitting source is expected to become worse with increasing off-axis distance of the focusing spot. Especially the electron beams far from the system optical axis have a non-negligible asymmetric intensity distribution in the micro-column. In this paper, the effect of the off-axis e-beam source is analyzed. To analyze this effect is to introduce a micro-column model of which the e-beam emitting source is aligned with the center of the electron beam by shifting them perpendicular to the system optical axis. The presented solution can be used to analysis the performance of the multi-electron-beam system. The performance parameters, such as the working distances and the focusing position are obtained by the computational simulations as a function of the off-axis distance of the emitting source.

• Journal of the Korean housing association
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• 제12권2호
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• pp.143-150
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• 2001

The purpose of this study is to analyze the preferences for urban residence. Data was collected from the people who are working in the CBD area. The results of this study are as following; 1) The 40.3% of people working in CBD area prefer living in the CBD area. It contains 5.6% of people who are working in the CBD area. It can be interpreted that there are some potential residential preference in the CBA area. 2) People who prefer living in the CBD area are shown that they have been working in the CBD area for a long time with their living status of the middle class and their ages over 50. 3) The favorable area for CBD workers is located within 10 minutes by bus or within working distance. 4) Their favorable housing types are respectively apartments, mixed, and single housing. It means that they prefer the mixed functioning type of housing to the apartment. It tells that it is necessary to develop the new types of housing.

• Journal of Advanced Marine Engineering and Technology
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• 제30권8호
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• pp.934-940
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• 2006

The aims of this study is to develop working robot for a installed trolley cable of an electric train and objective of this paper is to implement mobile control of working robot. In this paper an approach to method for scheme of a mobile control system is presented in a dynamic hybrid velocity/tension control of working robot. The working robot is composed the velocity and tension controllers using the concept of two-degrees-of-freedom servo-controller. This robot moved at same time a certain distance to constrain a constant tension and installed a trolley cable of an electric train. To move the robot the velocity control system have design and implemented. Simulation and experimental results are presented to illustrate the validity of designed mobil scheme.

• The Bulletin of The Korean Astronomical Society
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• 제40권1호
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• pp.46.2-46.2
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• 2015

Modern methods in determining the value of the Hubble constant are divided into two main ways: the classical distance ladder method and the inverse distance ladder method. The classical distance ladder method is based on Cepheid calibrated Type Ia supernovae (SNe Ia), which are known as powerful distance indicator. The inverse distance ladder method uses cosmic microwave background radiation, which emitted from the high-z universe, and the cosmological model. Recent estimations of the Hubble constant based on these two methods show a $2{\sim}3{\sigma}$ difference, which called the "Hubble tension". It is currently an issue in the modern cosmology. We have been working on the luminosity calibration of SNe Ia based on the Tip of the Red Giant Branch (TRGB), which is a precise population I distance indicator. We present the TRGB distance estimates of 5 SNe Ia host galaxies with the archival Hubble Space Telescope image data. We derive the mean absolute maximum magnitude of 5 SNe Ia and the value of the Hubble constant. Cosmological implications of our estimate will be discussed.

• Journal of the Korean Society of Costume
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• 제58권7호
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• pp.43-59
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• 2008

This study aims to improve the uniform functionality of the workers who work in Electric Technology Division, Korea Railroad Corporation. Former study of questionnaire survey was taken to examine the current state of wearing working clothes for the workers. Based on the results of the former study, an experimental clothes, the functionality of which has improved in terms of design, materials, and patterns, was created, and existing working clothes and the treated experimental clothes were compared through simulation wearing evaluation comprising appearance, activity adaptability, quantitativeness, and on-site adaptability evaluation comprising appearance and activity adaptability. The followings are the results of the study: Simulation wearing evaluation is composed of 5subjects and 11experts specializing in costume, and as a result of evaluation the experimental clothes were evaluated superior to the existing working clothes in all items. On-site adaptability evaluation was conducted by workers in the Electric Technology Division, who are the subjects in this study. In that evaluation, the experimental clothes were also evaluated superior to the existing working clothes in all items. While the five subjects who participated in the simulation wearing evaluation move, the quantitative evaluation measured the distance of location transfer of the back length in the jacket and the distance of location transfer of the back waist in the trousers. As the distances in the experimental clothes were measured shorter than the distances in the existing working clothes, the subjective evaluation results are objectively supported.

• Journal of Biomedical Engineering Research
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• 제28권2호
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• pp.265-270
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• 2007

Polarization imaging systems have been widely used to selectively characterize skin lesions. Nevertheless, current systems are used in single-mode due to the limitations of a fixed polarization mode and a single-working distance of light source, in which uniform light distribution is achieved on target area. To address such limitations, we developed a variable polarization imaging system based on multi-working distance of light source for various clinical diagnoses. In this study, we characterize the imaging system and present experiment results demonstrating its clinical usefulness. The imaging system consists of a CCD color camera, linear polarization filters, and a single-layered LED ring light source which provides uniform light distribution at multi-working distances. The first polarizer was placed on the light source and the second polarizer placed on objective lens provides continuous linear polarization angle from $0^{\circ}\;to\;90^{\circ}$. The clinical efficacy of the imaging system was investigated by acquiring and analyzing clinical images of skin wrinkle and dental plaque. With the experiments, we verified the potential usefulness of the imaging system for other clinical applications.