• Journal of Advanced Navigation Technology
• /
• v.19 no.3
• /
• pp.224-229
• /
• 2015

In this paper, we derived the design equation and implemented the unequal Gysel power divider that is one external resistors using the ABCD parameters analysis. Conventional unequal Gysel divider is difficult to obtain the characteristics of isolation and return loss at between output ports because it can't select a theoretical value of external resistor. To solve those problems, we design the new unequal Gysel power divider with transmission lines and one external resistor that has the characteristics of conventional unequal Gysel divider. To validate this design method, we simulated and measured an 4: 1 unequal Gysel power divider at the center frequency 1 GHz. The measured performances agreed well with the simulation results.

• Journal of Digital Convergence
• /
• v.12 no.2
• /
• pp.183-191
• /
• 2014

SNS uses the Internet as its base. It is created in order to achieve communication between the users. Up until now, most previous research were focused on the users of SNS. But, there are still a great deal of people who do not use or discontinuously use SNS. This is because users have natural resistance against SNS when using the service. In this study, time shortage perception, awareness of SNS, self-efficacy, suitability, information quality of SNS, subjective norm and privacy concern are considered as influence factors by previous research. An empirical study for Chinese students and internet users was conducted to identify how these factors influence perceived risk and perceived usefulness, and how this influence to user's resistance. This study can explain the reason why users don't use SNS and resist SNS use.

• KOREAN JOURNAL OF CROP SCIENCE
• /
• v.47 no.3
• /
• pp.226-235
• /
• 2002

This experiment was to evaluate lodging characteristics of 35 recommended rice varieties of Kyonggi-do at normal (110 kg N/ha) and hen (220 kg N/ha) nitrogen application rates during 1999 to 2000. At heavy N fertilization rate, varieties that were highly resistant to lodging were Obongbyeo, Daejinbyeo, Naepoongbyeo, Nonganbyeo and Ilpumbyeo. Fourteen varieties including Daeanbyeo were moderately resistant and 11 varieties including Jinbubyeo were susceptible to lodging. The lodging-related characters which showed the highest effect on lodging at lodging degree of 9 were culm length and height of center gravity, culm length at lodging degree of 5, and culm length and the third internode length at lodging degree of 3 or below. The difference in rice yield between normal and heavy nitrogen fertilization rate was within 5% in early-maturing varieties but there was great yield difference in mid- and late-maturing varieties depending on the degree of lodging. Consequently, stable rice yield could be obtained by selecting lodging-resistant varieties and lowering fertilization rate, specially in the paddy field where lodging occurrence is common.

• Journal of the Korean Ceramic Society
• /
• v.38 no.11
• /
• pp.973-979
• /
• 2001

Tin-doped indium oxide (ITO) thin films were deposited using r.f. magnetron reactive sputtering and the electrical properties, such as the resistivity, carrier concentration and mobility, were investigated as a function of the sample position under a given magnetron sputtering condition. The nonhomogeneity of the electrical properties with the sample position was observed under a given magnetron sputtering condition. The resistivity of ITO thin film on the substrate which corresponded to the center of the target had a minimum value, 2∼4$\times$10$\^$-4/$\Omega$$.$cm, and it increased symmetrically when the substrate deviated from the center. The density measurement result also showed that ITO thin film deposited at the center has a maximum density of 7.0g/cm$^3$, which was a relative density of about 97%, and the density decreased symmetrically as the substrate deviated from the center. The nonhomogeneity of electrical properties with the deposition position could be explained with the incidence angle of the source beam alpha, which is related with an atomic self-shadowing effect. It was confirmed experimentally that the density in film affect both the carrier mobility and the conductivity. In the case where the density of ITO thin film is 7.0g/cm$^3$, the magnitude of the mean free path was identical with that of the grain size(the diameter of column). However, in the other cases, the mean free path was smaller than the grain size. These results showed that the scattering of the free electrons at the grain boundary is the major factor for the electrical conduction in ITO thin films having a high density, and there exists other scattering sources such as vacancies, holes, or pores in ITO thin films having a low density.ing a low density.

• The korean journal of orthodontics
• /
• v.33 no.4 s.99
• /
• pp.259-277
• /
• 2003

This study was designed to investigate the position of anteroposterior center of resistance for genuine intrusion and the mode of change of the minimum distal force for simultanous intrusion and retraction of the upper and lower incisors according to the increase of labial inclination. For this purpose, we used the three-piece intrusion arch appliance and three-dimensional finite element models of upper and lower incisors. 1. Positions of the center of resistance in upper incisors according to the increase of the labial inclination were as follows; 1) In normal inclination situation, the center of resistance was located in 6m behind the distal surface of the lateral incisor bracket. 2) In $10^{\circ}$ increase of the labial inclination situation, the center of resistance was located in 9mm behind the distal surface of the lateral incisor bracket. 3) In $20^{\circ}$ increase of the labial inclination situation, the center of resistance was located in 12m behind the distal surface of the lateral incisor bracket. 4) In $30^{\circ}$ increase of the labial inclination situation, the center of resistance was located in 16m behind the distal surface of the lateral incisor bracket. 2. Positions of the center of resistance in lower incisors according to the increase of the labial inclination were as follows; 1) In normal inclination situation, the center of resistance was located in 10mm behind the distal surface of the lateral incisor bracket. 2) In $10^{\circ}$ increase of the labial inclination situation, the center of resistance was located in 13m behind the distal surface of the lateral incisor bracket. 3) In $20^{\circ}$ increase of the labial inclination situation, the center of resistance was located in 15m behind the distal surface of the lateral incisor bracket. 4) In $30^{\circ}$ increase of the labial inclination situation, the center of resistance was located in 18m behind the distal surface of the lateral incisor bracket. 3. The patterns of stress distribution were as follows; 1) There were even compressive stresses In and periodontal ligament when intrusion force was applied through determined center of resistance. 2) There were gradual increase of complexity in compressive stress distribution pattern with Increase of the labial inclination when intrusion and retraction force were applied simultaneously. 4. With increase of the labial inclination of the upper and lower incisors, the position of the center of resistance moved posteriorly. And the distal force for pure intrusion was increased until $20^{\circ}$increase of the labial inclination.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.15 no.3
• /
• pp.1-11
• /
• 2016

The present study aims to evaluate transfer resistance factors in railway stations and draw new implications. The data used for the model estimation are RP (revealed preference) data and SP (stated preference) data. Two types of models were used for the analysis: integration model which combined line-haul stage, transfer stage and shuttle stage and separation model which assessed the three stages separately. The results revealed that while bulk freight shippers mainly focused on line-haul stage, they put emphasis on transfer stage as well. It's especially notable that transfer stage was considered more important than shuttle stage. Therefore, in future transportation policies concerning rail freight, it would be crucial not only to enhance the competitiveness of line-haul stage but also make improvements in transfer stage regarding railway stations.

• Journal of the Korean Geographical Society
• /
• v.40 no.5 s.110
• /
• pp.553-570
• /
• 2005

On Kyeryong Mountain, different religious(or ideological) groups have endowed space and place with amalgams of different meanings, uses and values. In addition to Buddhism and Confucianism, Shamanism and other popular beliefs have practiced their own ideologies(or powers) to create and maintain their own territories and identities. The geographies of resistance, involving Shamanism, have been scattered all over the mountain, discontinuous in the territorialization. These geographies of resistance could be identified the best around the most sacred sites, such as Sambulbong, Amyongch'u and Sutyongch'u. The entanglement of Shamanism with Buddhism, in various patterns through space and time, has indeed contributed to the survival of Shamanism as a subordinate power.

• Proceedings of the Korean Nuclear Society Conference
• /
• 1996.11b
• /
• pp.527-532
• /
• 1996

Fe-Cr-Mn계 스테인리스강을 진공 용해하여 최적 소둔 조건인 1,20$0^{\circ}C$에서 30분동안 소둔 열처리한 후 미세 조직, 기계적 특성 및 부식 특성에 미치는 시효 열처리의 영향에 대하여 실험하였다. 미세 조직 분석은 광학 현미경 관찰, XRD분석, SEM분석, TEM분석 등으로 행하였고, 기계적 시험은 인장 시험, 충격 시험, 경도 시험을 행하였다. 부식 저항성을 평가하기 위해 황산, 염산분위기에서 양극 분극 시험을 행하였다. 시효 열처리에 따른 미세 조직간의 상분율 변화는 거의 없었지만 입계를 중심으로 제2상이 석출되었고, 그 양은 시효 시간이 증가함에 따라 증가하였다. 인장 강도 및 연신율은 낮은 시효 온도에서는 시효 온도와 시효 시간에 따라 큰 차이를 보이지 않았지만 고온으로 갈수록 시효 시간이 증가함에 따라 다소 감소하는 경향이 나타났다. 충격에너지는 1시간 시효시에는 시효 온도에 따라 큰 변화를 보이지 않았지만 10시간, 100시간 시효한 경우 시효 온도가 상승함에 따라 감소하였다. 이러한 경향은 고온에서 시효한 경우 입계성장이 가속화되어 나타난 것으로 판단된다. 시효 시간이 증가함에 따라 부식 환경에 관계없이 부식 저항성이 감소하였다. 85$0^{\circ}C$에서 시효한 경우 가장 우수한 내식성을 보였고, $650^{\circ}C$에서 낮은 내식성을 나타냈는데 이는 이 온도 구간에서 탄화물 등의 제2상의 석출에 의한 것으로 판단된다.

• 한국경영정보학회:학술대회논문집
• /
• 2007.11a
• /
• pp.445-452
• /
• 2007

2007 년 3 월 3.5 세대인 HSDPA 의 전국 서비스가 시작되면서 HSDPA 휴대전화는 영상통화를 중심으로 한 다양한 기능으로 소비자를 유혹하고 있지만 설문조사에 의하면 HSDPA 에 대해 소비자들은 과반수 이상이 필요성을 못 느끼고 있고 3 세대에서 2 세대로의 '역(逆) 번호이동'도 꾸준히 늘고 있는 것으로 나타났다. 이는 소비자들이 HSDPA 휴대전화라는 신기술에 대해 기술 수용과 혁신 저항을 동시에 하고 있는 것으로 판단된다. 따라서 기술 수용과 혁신 저항의 관점에서 연구를 진행하였다. 연구결과는 유용성, 편이성, 혁신제품의 특징, 더 좋은 제품 기대가 태도에 영향을 미치는 것으로 나타났고 자기효능, 복잡성, 지각된 위험, 기존 제품에 태도는 태도에 영향을 미치지 않는 것으로 나타났다.

• Proceedings of the KOR-KST Conference
• /
• 1998.10a
• /
• pp.42-51
• /
• 1998

안전한고 쾌적한 보행환경을 조성하여 보행 교통을 활성화시킨다면, 자동차의 사용이 줄게 되고 자동차의 유해한 배출가스로 인한 공기 오염 및 소음 등을 낮출 수 있을 뿐만 아니라 도심부의 미관 증대, 역사적 구역의 보존, 물리적인 도시 이미지 향상 등의 효과로 도심기능의 활성화에 기여할 수 있을 것이다. 이와 같은 보행통행의 중요성을 인식하여 안전하고 효율성 있는 보행동선을 조성할 필요가 있다. 그러나 상당수의 종합병원과 같은 공공성을 띤 건물들은 대부분의 보행자가 보행동선을 이용하여 건물에 접근하는데도 불구하고 차량을 중심으로 동선이 운영되고 있는 실정이다. 차량위주의 동선 체계는 보행 통행자로 하여금 차량통행으로의 전환을 유도할 가능성이 있어 이에 대한 대책이 필요하다. 본 연구는 분석대상으로 차량과 보행자에게 동등하게 접근의 용이성을 제공해야 하는 광주시의 4대 종합병원을 대상으로 보행자 집단에게 가해지는 저항이 구체적으로 얼마나 심각하며, 그 원인은 어떠한 물리적 조건에 의하여 발생하는지 알아 보았다. 보행저항을 파악하기 위한 지표로는 차량과 보행자의 충돌점의 수, 최단거리 선호도, 보행로 미확보율 등을 설정하여 분석하였다. 이러한 분석의 결과 나타난 문제점들을 해결하기 위한 방안도 함께 모색하였다.