• 농촌계획
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• 제14권1호
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• pp.23-32
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• 2008

Landscape structure is important to understand a complex patterns and interaction with adjacent habitat in rural area. The aim of this study is to analyze relationship between landscape structure and insect spatial distribution in rural area to suggest applicable possibility of landscape structure as biological indicator. For this purpose, first, four landscape structure criteria such as distance from the forest; density of farmland-forest ecotone; landscape continuity; and field size are selected. Secondly, these criteria are applied to Gangsang-myeon, Yangpyeong-gun where mosaic feature are conserved at various spatial scale. Thirdly, application of landscape structure criteria is verified using correlation with species number, species diversity, and species richness of insect. As a result, it could be suggested that the landscape structure criteria are useful for explaining insect spatial distribution.

• 한국포장학회지
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• 제23권2호
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• pp.103-108
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• 2017

The amount of delivered parcels have been increasing according to the change and expansion of consumption pattern through e-commerce, and they are required to minimize breakout or failure under the delivery. In this study, we measured and analyzed the distribution environment data (vibration and impact) occurred in the packaging, which were prepared with 5 types by the weight and dimension, distributed from Seoul to Busan in Korea by 2 parcel delivery service companies through e-commerce order. Date showed the parcels had 3-5 times of drop impact and 0.3-0.7 m of drop height on average, and 0.8 Grms of vibration acceleration from equivalent equation to the vertical direction. The significant gap in service quality was not found between 2 parcel delivery service companies. This study is expected to be useful for designing the suitable packaging in order to enhance safe transportation of the delivered packaging, and furthermore useful for developing Korean testing method for Field-to-Lab simulation.

• Radiation Oncology Journal
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• 제1권1호
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• pp.11-19
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• 1983

Interaction between high energyelectrons and matters had many complex reactions and the high energy electrons lost their energies with collision and scattering, therefore, electrons distribution in matters was shown as various situation by scattering, exciting and ionizing with moleculars. We experimentally studies with 13 MeV Linear Accelerator and thermoluminescence dosimeter using aluminium and Teflon, etc., and measured energy loss of electrons, electron range, electron scattering and dose distribution in matter. We compared the results with theoretical formular, between 4-qw MeV, the energy loss of electrons was decreased by 2 MeV per $1g/cm^2$ but under 1MeV it was rapidly decreased. Electron range in matter reached to $0.5/cm^2$ per 1MeV of incident energy at 6-12MeV. The dose distribution in matter was increased slightly to some depth by total distribution i.e., the combined intensity of primary and secondary radiant and it was rapidly decreased near the maximum range of electrons. Energy loss of electrons and electron range measured by experiment were coincided with theoretical equations of L. Landau and Feather under 5 and 3% errors respectively. The dose distribution of electrons in matter was similar to L.V. Spencer formular, however, we had found that it was quite different in accordance with the field size and that new formular of dose distribution was induced as empirical function contained experimental factors according to field size.

• 한국초전도저온공학회:학술대회논문집
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• 한국초전도저온공학회 1999년도 제1회 학술대회논문집(KIASC 1st conference 99)
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• pp.81-84
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• 1999

The purpose of this paper is to find the magnetic field distribution inside the motor in order to find out if the high-Tc superconducting tapes operate stably in actual motor operation. With this gola, magnetic field distribution in a detailed model of the actual motor was analyzed through F.E.M. (Finite Element Method). As a result, it has been proved that the high-Tc superconducting tapes can withstand 4 A of current with stability. 4 A was the amount of current needed to achieve 600 A ·turns which is required by the previous simulation aimed at developing this motor. Also, it has been observed that the flux damper reduces armature reactance during the motor operation and during load changes, helping the stable motor operation. But, it was observed that the flux damper generates loss by means of leakage flux and this decreases the output of the motor by about 5%.

• 유통과학연구
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• 제18권8호
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• pp.103-112
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• 2020

Purpose: Business has been completely revolutionized by the Internet. This study seeks to determine the impact of e-business on activity extension and business performance. It aims to examine the actual stage of e-business, help others to apply the knowledge gained, and help in expanding new researches in this field. Research design, data and methodology: The data utilized in this study was obtained from survey. In total of 60 questionnaires accepted as valid out of 80 distributed, data was analyzed using the SPSS, and methods used were correlation and reliability analyses. Results: The study result shows that e-business has a significant positive impact on activity extension and the performance of business in Kosovo. The findings also revealed that there is a correlation between the various online marketing strategies and consumer satisfaction. The development of e-business for Kosovo is an important factor in participation in the world market, where there is a growing need for innovation and modernization of business. Conclusions: The study recommends that there should be raised awareness among business owners and managers as well as the general public. Moreover, there should be a proper application of marketing strategies to e-business.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2007년도 제38회 하계학술대회
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• pp.731-732
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• 2007

This paper presents the final configuration of test field and test items for the application of IEC 60364-4-44 in Korea. IEC 60364-4-44 provides rules for the protection against the effects of conducted and radiated disturbances on electrical installations. Especially this standard deals with the protection of low voltage facility against the ground fault in the high voltage side of power distribution system. Many countries define the regulations on the use of electrical facilities based on their own power system and technical references which are considered to be suitable for them. The background of circuit of IEC 60364-4-44 is based on the ungrounded system as most of European countries. However, domestic electric power distribution system is based on multi-grounding system different from European system. Therefore, it is necessary to evaluate or prove the effect of the IEC 60364-4-44 for introducing and applying it to the domestic grounding system as a national standard. The authors with KEA(Korea Electric Association) carried out a project on the application of IEC 60364-4-44 to Korean electrical installations of buildings sponsored by Korean ministry of commerce, industry and energy for three years(2004.4.1$\sim$2007.3.31). The test field is established in K.E.R.I.(Korea Electrotechnology Research Institute), which is the purpose of evaluating the formula to calculate touch voltage and stress voltage in the IEC standards. This paper presents some considerations and final configuration of test field to evaluate and introduce the IEC 60364-4-44 applicable to domestic rule for the protection against ground fault.

• Steel and Composite Structures
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• 제10권1호
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• pp.87-108
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• 2010

A Steel Plate Shear Wall (SPSW) is a lateral load resisting system consisting of an infill plate located within a frame. When buckling occurs in the infill plate of a SPSW, a diagonal tension field is formed through the plate. The study of the tension field behavior regarding the distribution and orientation patterns of principal stresses can be useful, for instance to modify the basic strip model to predict the behavior of SPSW more accurately. This paper investigates the influence of torsional and out-of-plane flexural rigidities of boundary members (i.e. beams and columns) on the buckling coefficient as well as on the distribution and orientation patterns of principal stresses associated with the buckling modes. The linear buckling equations in the sense of von-Karman have been solved in conjunction with various boundary conditions, by using the Ritz method. Also, in this research the effects of symmetric and anti-symmetric buckling modes and complete anchoring of the tension field due to lacking of in-plane bending of the beams as well as the aspect ratio of plate on the behavior of tension field and buckling coefficient have been studied.

• 한국ITS학회 논문지
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• 제11권3호
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• pp.23-30
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• 2012

본 논문에서는 근접 영역에 적용할 수 있는 새로운 900 MHz RFID 리더기 안테나에 대한 연구 결과를 제안한다. 본 논문에서 제안된 안테나는 주기성을 갖는 마이크로 스트립 안테나 구조를 사용하였다. 안테나의 크기는 $313mm{\times}152mm{\times}14mm$ 이다. 안테나의 성능은 근접영역에서 균일한 전계 분포를 갖고, 안테나의 이득은 -2 dBi 이고 하트 모양의 빔 패턴을 가진다. 제안된 안테나는 리더기의 송신출력이 17 dBm에서 23 dBm까지의 범위를 보인다. 본 논문에서 제안된 안테나는 금속면 위에 태그가 선적이 될 때 태그의 금속성분으로 인한 반사전력을 최소화하고 외부로 방사되는 전력을 최소화하여 오인식을 최소화하였다.

• 대한전기학회:학술대회논문집
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• 대한전기학회 2001년도 추계학술대회 논문집 전기물성,응용부문
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• pp.205-207
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• 2001

This study is characteristic analysis to optimize triggering of a high-power trigatron by FEM which is used to analyse electric field distribution in the trigatron. Triggering characteristics of a trigatron depends on arrangement of voltage polarity applied on electrodes and configuration of electrodes. This study is the preliminary stage for an experiment and make it possible to experiment effectively by finding optimal triggering characteristics though 3-dimensional node-based FEM which can practically model the complex structured electrode system.

• Journal of Plant Biology
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• 제37권4호
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• pp.403-410
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• 1994

The taxonomic criterion between Erythroglossum and Sorella was reappraised based on Korean plants of E. minimum Okamura and S. repens (Okamura) Hollenberg. Development of the reproductive organs was observed from field collected plants as well as cultured plants. The Polyneura-tuype procarp which comprised one group of sterile cells and two carpogonial branches arising from a supporting cell was observed in both species. Distribution of tetrasporangial sori was irregular in both species, so it is not relevant to distinguish Sorella from Erythroglossum by the characteristic of tetrasporangial distribution. E. minimum and S. repens were very similar in vegetative form, but were reproductively isolated. Chromosome numbers were given as n=ca. 30 in S. repens and n=ca. 41 in E. minimum, respectively.