• 대한간호학회지
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• 제34권2호
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• pp.213-224
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• 2004

Purpose: This study was aimed to evaluate the effect of progressive muscle relaxation training using biofeedback on perceived stress, stress response, immune response and climacteric symptoms, Method: This was a crossover, pre-post test design, The study subjects are 36 middle-aged women who were selected at 2 public health centers, The independent variable was Biofeedback training for 4 weeks, twice a week and home training for 4 weeks, Dependent variables were perceived stress, stress response, immune response, and climacteric symptoms measured with Hildtch's scale (1996), Result: Progressive muscle relaxation training using biofeedback was not effective in reducing perceived stress, but it was shown to be effective in reducing physiological stress responses such as pulse rate and EMG, Though blood pressure and skin conductance were repeatedly down, and skin temperature slowly increased, there were no statistically significant differences. Progressive muscle relaxation training using biofeedback was not effective in reducing serum cortisol, enhancing immune responses, or decreasing climacteric symptoms. Conclusion: The findings point to a pressing need for further, well-controlled and designed research with consideration in selection of subjects and instruments, frequency of measurements, the sampling method, and intervention modalities.

• 한국공간구조학회논문집
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• 제19권1호
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• pp.53-64
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• 2019

The objective of this study is to investigate the earthquake response for the design of 100m spanned single-layer lattice dome. The plastic hinge analysis and eigenvalue buckling analysis are performed to estimate the ultimate load of single-layered lattice domes under vertical loads. In order to ensure the stability of lattice domes, it is investigated for the plastic hinge progressive status by the pushover increment analysis considering the elasto-plastic connection. One of the most effective methods to reduce the earthquake response of large span domes is to install the LRB isolation system of a dome. The authors discuss the reducing effect for the earthquake dynamic response of 100m spanned single-layered lattice domes. The LRB seismic isolation system can greatly reduce the dynamic response of lattice domes for the horizontal and vertical earthquake ground motion.

• Structural Engineering and Mechanics
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• 제24권3호
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• pp.275-290
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• 2006

In this paper, the performance of a tuned liquid damper (TLD) in suppressing the seismic response of buildings is investigated with shake table testing of a four-story steel frame model that rests on pile foundation. The model tests were performed in three phases with the steel frame structure alone, the soil and pile foundation system, and the soil-foundation-structure system, respectively. The test results from different phases were compared to study the effect of soil-structure interaction on the efficiency of a TLD in reducing the peak response of the structure. The influence of a TLD on the dynamic response of the pile foundation was investigated as well. Three types of earthquake excitations were considered with different frequency characteristics. Test results indicated that TLD can suppress the peak response of the structure up to 20% regardless of the presence of soils. TLD is also effective in reducing the dynamic responses of pile foundation.

• 한국공간구조학회논문집
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• 제18권3호
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• pp.105-116
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• 2018

The objective of this study is to investigate the response reducing effect of a seismic isolation system installed between 300m dome and supports under both horizontal and vertical seismic ground motion. The time history analysis is performed to investigate the dynamic behavior of single layer lattice domes with and without a lead rubber bearing seismic isolation system. In order to ensure the seismic performance of lattice domes against strong earthquakes, it is important to investigate the mechanical characteristics of dynamic response. Horizontal and vertical seismic ground motions cause a large asymmetric vertical response of large span domes. One of the most effective methods to reduce the dynamic response is to install a seismic isolation system for observing seismic ground motion at the base of the dome. This paper discusses the dynamic response characteristics of 300m single layer lattice domes supported on a lead rubber seismic isolation device under horizontal and vertical seismic ground motions.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 1999년도 가을 학술발표회 논문집
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• pp.214-224
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• 1999

The design response spectrum has been widely used in seismic design to estimate force and deformation demands of structures imposed by Earthquake Ground Motion (EQGM). Inelastic Design Response Spectra (IDRS) to specify design yielding strength in seismic codes are obtained by reducing the ordinates of Linear Elastic Design Response Spectrum (LEDRS) by strength reduction factor (R). Since a building is designed using reduced design spectrum (IDRS) rather than LEDRS in current seismic design procedures it allows structures behave inelastically during design level EQGM. Inelastic Response Spectra (IRS) depend not only on the characteristics of the expected ground motion at a given site, but also on the dynamic properties and nonlinear characteristics of a structure. However, it has not been explicitly investigated the effect of different hysteretic models on IRS. In this study, the effect of hysteretic models on IRS is investigated.

• 한국조사연구학회지:조사연구
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• 제7권2호
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• pp.71-95
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• 2006

이 글에서는 복잡한 설문구조를 가진 사회조사에서 CAPI를 활용할 때 나타날 수 있는 장점을 고령화연구패널조사(Korean Longitudinal Study of Ageing: KLoSA) 제1차년도 조사 및 예비조사에서 실제 작성한 CAPI 설문 사례를 가지고 살펴보았다. 특히 CAPI 활용이 자료의 질(data quality)을 어떻게 향상시켜 줄 수 있는가에 초점을 맞추어 다음과 같은 다섯 가지 측면에서 살펴보았다. 첫째, CAPI는 설문 논리와 경로 구조화, 응답 범위 설정, 응답 일관성 유지 등을 통하여 응답 오류를 줄여준다. 둘째, 응답자 맞춤식 설문 문항 작성, 자동 계산 및 채점, 도움말 탑재 등을 통하여 면접의 편의성을 제고시켜 준다. 셋째, 설문 문항의 순서를 무작위로 배치할 수 있어서 보기 순서 효과나 문항 순서 효과를 방지하여 준다. 넷째, 항목 무응답을 감소시켜 응답률을 높이는 효과가 있다. 다섯째, 면접 상황을 모니터링하여 설문을 개선하거나 면접원을 감독하는 데에 도움을 준다. CAPI가 가진 이와 같은 특성은 면접 과정에서 발생할 수 있는 오류를 감소시키고, 또한 면접 편의성을 제고하여 면접의 흐름을 자연스럽게 만들어준다.

• 전기학회논문지
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• 제66권8호
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• pp.1181-1186
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• 2017

The purpose of Demand Response is to reduce the cost of excessive resources and equipment by spontaneous load reductions at peak loads. Having enough power consumers participating in these schemes is key to achieving the goal. Demand Response Aggregator (DRA) is responsible for recruiting demand resources and managing them to participate in reducing the load. DRAs change the price elasticity of demand functions by providing incentives to demand response, thereby affecting price formation in the electricity market. In this paper, this process is modeled to analyze the relationship between DRA's strategic bidding and market outcomes and load reductions. It analyzes the results by applying to competition between DRAs, competition between DR and Gencos, and coexistence of DR load and non-DR load. It is noteworthy that we have found a phenomenon called the Balloon Effect.

• 한국축산식품학회지
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• 제38권3호
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• pp.570-579
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• 2018

The study investigated antioxidative properties and rectal cancer cell inhibition effect of amaranth (Amaranthus cruentus L.) cauline leaves (ACL) to produce the sausage with ACL powder (ACLP). Antioxidative effects of ACLP prepared with different stem lengths (10-45 cm) were evaluated through DPPH, ABTS, reducing power, total phenol, and total flavonoid. Inhibition effect on rectal cancer cells growth was also examined with CT-26 cell. To determine appropriate ACL amounts in sausage formula, response surface methodology was used. The sausages without ACL (control) and the sausage with ACL (ACLP sausage) were the subjected to the examinations of antioxidation, growth inhibition on CT-26, and physicochemical properties (pH and water content). ACLP made from the leaf with 15 cm length stem generally showed the highest antioxidative effect through results of DPPH, ABTS, reducing power, total phenol, and total flavonoid. ACLP also showed inhibition effect on the proliferation of CT-26, depending on concentration of ACLP. The surface response model showed that 4.87 g of ACLP was optimized amount for sausage production. Physicochemical properties between optimized ACLP and control sausages were not significantly different. Higher antioxidative effect of optimized ACLP sausage extract was observed (p<0.05) in antioxidation tests than control sausage extract except for DPPH. Cell viability of CT-26 cells were higher (p<0.05) in ACLP than in control sausage extracts. These results indicate that ACLP has functional effects on antioxidation activity and growth inhibition on CT-26 cell, and thus, it should be useful as a supplement in sausage, which may some effect as ACLP itself.

• Interaction and multiscale mechanics
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• 제5권4호
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• pp.347-368
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• 2012

Measuring the bridge frequencies indirectly from an instrumented test vehicle is a potentially powerful technique for its mobility and economy, compared with the conventional direct technique that requires vibration sensors to be installed on the bridge. However, road surface roughness may pollute the vehicle spectrum and render the bridge frequencies unidentifiable. The objective of this paper is to study such an effect. First, a numerical simulation is conducted using the vehicle-bridge interaction element to demonstrate how the surface roughness affects the vehicle response. Then, an approximate theory in closed form is presented, for physically interpreting the role and range of influence of surface roughness on the identification of bridge frequencies. The latter is then expanded to include the action of an accompanying vehicle. Finally, measures are proposed for reducing the roughness effect, while enhancing the identifiability of bridge frequencies from the passing vehicle response.

• 한국기계가공학회지
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• 제19권9호
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• pp.71-77
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• 2020

In recent years, as a consequence of the technological advancements in the automobile industry and changes in consumer demands, the reduction of noise inside vehicles rather than vehicle performance has increasingly become an important factor of interest. To date, most studies have focused on noise and vibration reduction techniques for the engine and drive system of vehicles. In this research, a comparative analysis for reducing the effect of vehicle seatbelts on the transient response is performed using the test of vehicle conditions and transient response analysis in accordance with seatbelt conditions. After the sensitivity analysis, the specifications for improvement were designed based on the transient response analysis. It was confirmed that the transient response characteristics were improved by the transient response analysis and vehicle conditions test. Through computer-aided engineering, the transient response characteristics of seatbelts were checked with less cost and time.