• Structural Engineering and Mechanics
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• 제40권2호
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• pp.167-190
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• 2011

In order to upgrade the seismic resistibility of structures and enhance the functionality of an isolator, a new base isolator called the multiple trench friction pendulum system (MTFPS) is proposed in this study. The proposed MTFPS isolator is composed of a trench concave surface and several intermediate sliding plates in two orthogonal directions. Mathematical formulations have been derived to examine the characteristics of the proposed MTFPS isolator possessing numerous intermediate sliding plates. By means of mathematical formulations which have been validated by experimental results of bidirectional ground shaking, it can be inferred that the natural period and damping effect of the MTFPS isolator with several intermediate sliding plates can be altered continually and controllably during earthquakes. Furthermore, results obtained from the component and shaking table tests demonstrate that the proposed isolator provides good protection to structures for prevention of damage from strong earthquakes.

• 한국식생활문화학회지
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• 제4권2호
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• pp.191-197
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• 1989

Before Jin (秦) period, Oriental (Eastern) culture was established in Korea different from China. Bulgogi (babecued beef, 貊炙) and legume fermented soy were transmitted into China. Afterward, alcohol drink, rice cake and cookie, shic-hae (lactic acid fermented fish products), Kimchi (fermented vegetable) were introduced and modified for Korea. Buddhism was transmitted to Korea through China, but selective animal was used as food. Later period of Koryo Dynasty, meat-eating become common due to mongorian influence and distilled spirits was introduced by mongorian. During Chosun Dynasty, table setting of spoon and chopstick was established, due to Confucian influence, dog eating, raw fish and raw meat eating became popular and nutrition for elderly was developed, whereas tea culture declined. In recent period (under the Japanese rule) Chinese introduced chinese noodle, chinese cuisine, chinese pancake and sun-dried salt. many chinese cultivated chinese vegetables.

• 대한가정학회지
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• 제24권4호
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• pp.139-146
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• 1986

The purpose of this study was to identify aesthetic concepts of‘Sarangbang’furniture during the Yi-dynasty period and aesthetic descriptions indicating each concept expressed by experts in traditional furniture. The furniture selected for the study includes desks, table bookcases, document and stationary boxes (mungab), letter holders (Kobi) and inkstone boxes (younsang) with lacquer and oil finish on. The respondents were 72 traditional furniture experts; researchers collectors, sellers and artists related to period furniture. The important points of aesthetic descriptors were collected 123 from related literature. From experts' answers, 47 representative descriptors were selected. Data were analyzed with the SPSS using frequency, Percentage mean, factor analysis, t-test and C2. The results were as follows; 1. The aesthetic concept of sarangbang furniture during the Yi-dynasty can be categorized into 9 aspects; appearance of beauty, stability the interior space, naturalness, nobleness/harmony of lines, detail/refinement, simplicity, diversity solidity and surface division. 2. The characteristics of the Korean traditional furniture can be described using 47 descriptors explaining 9 concepts mentioned above.

• 보험의학회지
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• 제27권2호
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• pp.96-106
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• 2008

다음은 위의 모든 결과를 바탕으로 디스크 질환의 입원기간이 길어지고 재발이 일어날 수 있는 나쁜 조건 (NEGATIVE)과 그 반대인 좋은 조건(Positive)을 table로 정리하였다. 좋은 조건은 같은 추간판 탈출 기왕력자라고 하더라도 예후에 긍정적인 가능성을 주는 조건이다. 따라서 심사할 때 table를 토대로 고지내용이 좋은 조건인지, 나쁜 조건인지 판단 할 수 있고 추가 질문사항을 요청하는데 도움이 될 수 있을 것이다. 만약 입원을 했더라도 며칠을 입원했는지. 재수술을 하였다면 어떻게 했는지, 직장인의 경우 현재 어떤 조건인지, 수술을 했다면 구체적으로 수술명이 무엇인지, 수술 후 술, 담배를 하였는지, 수술 후 현재 상태가 어떤지에 따라 인수 여부를 결정하는데 도움이 될 것이라고 생각한다.

• 한국방재학회 논문집
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• 제7권4호
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• pp.67-74
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• 2007

합리식은 구조가 간단하고 사용하기 편리하기 때문에 소배수유역의 우수관거 설계에 가장 많이 사용되고 있다. 합리식을 이용한 유출해석에서 가장 중요한 요소인 유출계수 값은 강우강도, 재현기간, 강우의 지속시간, 지표특성 등에 따라 달라지지만 토지이용도에 따라 제시된 일정한 값을 그대로 사용하고 있다. 그러므로 실무자들이 합리식을 이용하여 우수관거 설계를 위한 적정 설계홍수량 산정을 위해서는 유출계수에 영향을 미치는 중요한 인자들을 고려한 통합유출계수의 산정이 필수적이다. 따라서 본 연구에서는 합리식에 대한 기본이론을 검토하고 유출계수에 영향을 미치는 주요인자와 유출과의 관계를 연구하여 합리식에서의 유출계수(C)와 강우지속시간, 재현기간(T) 및 NRCS(Natural Resources Conservation Service)방법에서 CN(유출곡선지수)와의 관계를 연구하여 보다 합리적으로 유출계수를 산정할 수 있도록 하였다.

• 중소기업융합학회논문지
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• 제5권4호
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• pp.5-10
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• 2015

ICT 발달로 인해 네트워크의 상태를 파악하고, 분석하는 네트워크 모니터링이 중요한 이슈가 되었다. TCP/IP 네트워크 상에서 SNMP는 폴링기법을 이용하여 네트워크 상태를 파악하는 대표적인 프로토콜이다. 폴링기법을 긴 주기로 시행했을 때 네트워크 상태 변화를 제대로 파악하기 어렵다. 반면에 그 주기가 짧으면 실시간으로 네트워크 상태를 파악할 수 있겠지만 폴링결과에 대한 응답메시지로 인해 트래픽이 증가하여 네트워크에 부담이 된다. 폴링 주기를 조절하므로 폴링 응답메시지에 대한 오버헤드를 조절하기 위한 논문들이 제안되었다. 하지만, 에이전트의 특성을 고려하지 않고, 랜덤하게 실시하여 일시적인 효과일 뿐 효율적으로 오버헤드를 줄이지 못한다. 이 논문에서는 폴링 트래픽의 오버헤드를 줄이면서 네트워크 상태를 실시간으로 파악할 수 있는 효율적인 폴링 기법을 제안한다. 제안 기법은 폴링주기를 짧게 실시하면서 네트워크 상태를 실시간으로 파악하기 위해 에이전트의 특성에 따라 가중치를 부여하고, 가중치에 따라 매니저가 차등적으로 폴링을 실시여부를 결정하여 폴링 트래픽에 대한 오버헤드를 줄였다.

• Structural Engineering and Mechanics
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• 제84권2호
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• pp.155-165
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• 2022

The use of electricity and communication between electronic devices is increasing daily, which makes the stability of electrical power supply vital. Since the 1990s, large earthquakes have occurred frequently causing considerable direct damage to electrical power facilities as well as secondary damage, such as difficulty in restoring functions due to the interruption of electric power supply. Therefore, it is very important to establish measures to protect electrical power facilities, such as transformers and switchboards, from earthquakes. In this study, a 154 kV transformer whose service life had expired was installed on the base fabricated by simulating the field conditions and conducting the shaking table tests. The dynamic characteristics and seismic behavior of the 154 kV transformer were analyzed through the resonance frequency search test and seismic simulation test that considers the front, rear, left, and right directions. Since the purpose of this study is to analyze the acceleration amplification in the bushing due to the acceleration amplification, the experimental results were analyzed focusing on the acceleration response and the converted acceleration amplification ratio rather than the failure due to the displacement response of the transformer. The seismic force amplification at the transformer bushing was evaluated by simulating the characteristics of electrical power facilities in South Korea, and compared with the IEC TS 61463 acceleration amplification factor. Finally, the amplification factor at zero period acceleration (ZPA) modified for each return period was summarized. The results of this study can be used as data to define the amplification factor at ZPA of the transformer bushing, simulating the characteristics of electrical power facilities in Korea.

• 한국인구학
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• 제29권3호
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• pp.51-72
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• 2006

우리나라의 노동생명표 대부분은 Wolfbein & Wool의 전통적 방법에 의해 작성되고 있다. 그러나 여성의 경제활동참가율이 M자 형태를 보이므로, 이러한 방법은 여성의 노동기대여명 측정에 부적합하다. 한편. 증감 노동생명표는 여성에게도 동일하게 적용될 수 있으나, 개인의 경제활동 상태 전이에 대한 자료가 필요하다. 본 연구는 Garfinkle과 Pollard et al.의 노동생명표가 Hoem, Schoen & Woodrow에 의해 개발되고, 미국 노동통계국이 채택하고 있는 증감 노동생명표와 본질적으로 동일하다는 점을 보여주고 있다. 또한 이들의 노동생명표는 전통적인 방법에 의한 생명표와 마찬가지로 일반적인 증감노동생명표처럼 개인의 경제활동 상태간 전이확률을 추정하지 않고, 공표된 거시적 경제활동참가율을 사용할 수 있는 장점이 있음을 보여주고 있다. 아울러, 통계청이 발표한 2000-2050년의 간이생명표를 바탕으로 성 연령별 경제활동참가율 전망치를 추정하고, Garfinkle-Pollard의 증감 노동생명표 방법론에 의한 노동기대여명을 전망하였다. 그 결과 2000년에서 2050년 동안 65세의 노동기대여명은 남자 5.8년에서 7.7년, 여자 4.1년에서 5.1년으로 증가되었다. 그러나, 65세 이상 고령자의 경우는 자료처리 방법 및 향후 사망확률 가정에 따라 노동기대여명이 다소 차이를 보였다. 정확한 노동기대여명의 측정 및 전망을 위해서는 고령자의 경제활동에 대한 상세한 자료가 필요함은 물론, 향후 사망력 가정에 대한 심층 연구가 수반되어야 할 것이다.

• 대한예방한의학회지
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• 제17권3호
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• pp.143-153
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• 2013

Objective : This study was done to define the treatment protocol of Traditional Korean Medicine for persistent allergic rhinitis, which might be necessary for conducting PRCT study. Methods : Data were collected by questionnaire from Korean Medicine doctors participated in the Conference of The Korean Oriental Medical Ophthalmology & Otolaryngology & Dermatology Society in October 2012. We investigated their treatment procedures for persistent allergic rhinitis in ordinary clinical settings. Their treatment patterns including annual treatment period, frequencies and treatment times were also investigated. Finally, we combined the national insurance covered or out-of-pocket treatments as treatment packages according to the response rates of each contents, and displayed them as treatment protocols for PRCT study. Results : 50 Korean medicine doctors described the informed consent and questionnaire. Response rates of each treatment procedure were listed in Table 2 to Table 5. Treatment periods, frequencies and treatment time of each visit were listed in Table 6. Finally, treatment packages which would be defined for PRCT were listed in Table 7 as treatment package 1(response rates were over 50%), package 2(response rates were over 25%), package 3(response rates were over10%). Conclusion : These results provide the rational background and preliminary sources of defining treatment packages for developing PRCT protocols.

• Smart Structures and Systems
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• 제25권2호
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• pp.155-167
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• 2020

This paper demonstrates a real-time hybrid substructuring (RTHS) shake table test to evaluate the seismic performance of a base isolated building. Since RTHS involves a feedback loop in the test implementation, the frequency dependent magnitude and inherent time delay of the actuator dynamics can introduce inaccuracy and instability. The paper presents a robust stability and performance analysis method for the RTHS test. The robust stability method involves casting the actuator dynamics as a multiplicative uncertainty and applying the small gain theorem to derive the sufficient conditions for robust stability and performance. The attractive feature of this robust stability and performance analysis method is that it accommodates linearized modeled or measured frequency response functions for both the physical substructure and actuator dynamics. Significant experimental research has been conducted on base isolators and dampers toward developing high fidelity numerical models. Shake table testing, where the building superstructure is tested while the isolation layer is numerically modeled, can allow for a range of isolation strategies to be examined for a single shake table experiment. Further, recent concerns in base isolation for long period, long duration earthquakes necessitate adding damping at the isolation layer, which can allow higher frequency energy to be transmitted into the superstructure and can result in damage to structural and nonstructural components that can be difficult to numerically model and accurately predict. As such, physical testing of the superstructure while numerically modeling the isolation layer may be desired. The RTHS approach has been previously proposed for base isolated buildings, however, to date it has not been conducted on a base isolated structure isolated at the ground level and where the isolation layer itself is numerically simulated. This configuration provides multiple challenges in the RTHS stability associated with higher physical substructure frequencies and a low numerical to physical mass ratio. This paper demonstrates a base isolated RTHS test and the robust stability and performance analysis necessary to ensure the stability and accuracy. The tests consist of a scaled idealized 4-story superstructure building model placed directly onto a shake table and the isolation layer simulated in MATLAB/Simulink using a dSpace real-time controller.