• 한국강구조학회 논문집
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• 제20권1호
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• pp.93-104
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• 2008

국내 시공 중인 현수교의 시공단계에 대한 신뢰성 해석을 통한 위험성 평가를 실시하였다. 본 논문의 주요 연구목표는 (1) 현수교주케이블 소선의 파단에 대한 신뢰성 해석, (2) 보강형 거더 가설 28단계에 대한 위험단계 결정, (3) 보강형 거더 가설중 시공관리에 대한 한계상태의 신뢰성 평가이다. 기존의 현수교에 대한 연구와 설계는 주로 경험적인 데이터에 의존해 왔으나 최근 조사된 자료에 의하면 교량의 완공 전에 발생하는 사고의 원인의 80%는 인간의 오류, 계획, 설계, 재료 및 하중의 불확실성과 관련되어 있다. 교량의 완성계에 대해서는 많은 연구가 수행되어왔으나 시공중의 불확실성에 대해서는 시방서나 지침 등으로 정리되어 있지 않은 부분이 많다. 개선된 선형 적 용적 응답면기법을 사용하여 예제교량의 시공단계에 대한 위험성 평가를 하였다.

• The Journal of Korean Physical Therapy
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• 제12권3호
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• pp.497-507
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• 2000

This study was performed to understanding on guidelines for using therapeutic modalities according to injury phases of soft tissue. Clinical decisions on how and when therapeutic modalities may be used should be based on recognition of signs and symptoms. as well as some awareness of the time frames associated with the various phases of the Healing process. The physical therapist must have a sound understanding of that process in terms of the sequence of the various process of healing stage. The results of this study are as follows: 1. Once an acute injury has occured, the healing process consists of the imflammatory response phase, the fibroblastic-repair phase, and the maturation-remodeling phase and can impede by various pathologic factors. 2. Modality use in the initial acute injury phase and the inflammatory response phase should be directed toward limiting the amount of swelling and reducing pain. 3. Modality use in the Fibroblastic repair phase may be change from cold to heat. The purpose of heat is to increase circulation to the injured area to promote healing. 4. During the Maturation-Remodeling phase, some type of heating modalities, ultrasound, or short wave and microwave diathermy should be used to increase circulation to the deeper tissue. In this phases, physical therapists must control training and conditioning habits to allow the injury to heal sufficiently.

• 동의생리병리학회지
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• 제25권2호
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• pp.359-364
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• 2011

The purpose of this research is to propose the range of five phases which need to be essentially included in the introductory course of Korean medicine, its significance and the relationship with applied subjects. The students in School of Korean Medicine participated in a survey to figure out the response rate and status of the five phases described in the textbooks. In the preparatory survey, 43 items in the phases were selected; in the main one, there were differences only in the response rate to respective items, not in the grade level. In addition, the survey for the present condition of the textbooks was conducted with six categories to see if there is description of the five phases. Based on the two results, the importance of 43 five phases items was classified into low, medium, and high levels. It is expected that the efficiency of education can be increased if 14 items included in high significance and 11 in medium, which are classified according to the findings of this study, must be instructed in the introductory course of Korean medicine, and if 18 items in low significance are used as reference materials.

• 한국콘텐츠학회논문지
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• 제9권9호
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• pp.235-242
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• 2009

이 연구는 생물테러리즘을 위기로 인식하고 생물테러리즘을 위기관리별로 어떻게 관리할 것인가에 대한 관리방안을 연구하는데 그 목적이 있다. 9.11 테러 이후 발생한 탄저균 테러는 전 세계에 생물병원체에 의한 공포감을 인식시켜 주었으며, 그 위험성이 강조된 사례이다. 본 연구결과 생물테러리즘 위기는 4단계로 구분하여 관리할 때 완화 및 예방단계에서는 테러리즘의 기준을 정하고, 대비를 하기 위하여 테러관련 법을 제정하고, 조기발견을 위한 감시체계를 확보해야 한다. 대비단계에서는 초동조치 팀을 편성하고 교육훈련을 통해 대응하는 요령을 숙달시켜야 하며, 각종 자원을 확보해야 한다. 대응단계에서는 숙달된 초동조치팀이 즉각 투입되어 현장 정리 및 확산을 방지해야 하며, 복구단계에서는 평가체제를 구축하여 조기에 정상적인 생활로 복귀할 수 있도록 조치해야 한다.

• 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.

• The Korean Journal of Ceramics
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• 제6권3호
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• pp.201-205
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• 2000

Fiber reinforced plastic (FRP) composites and ceramic matrix composites (CMC) which contain electrically conductive phases have been designed and fabricated to introduce the detection capability of damage/fracture detection into these materials. The composites were made electrically conductive by adding carbon and TiN particles into FRP and CMC, respectively. The resistance of the conductive FRP containing carbon particles showed almost linear response to strain and high sensitivity over a wide range of strains. After each load-unload cycle the FRP retained a residual resistance, which increased with applied maximum stress or strain. The FRP with carbon particles embedded in cement (mortar) specimens enabled micro-crack formation and propagation in the mortar to be detected in situ. The CMC materials exhibited not only sensitive response to the applied strain but also an increase in resistance with increasing number of load-unload cycles during cyclic load testing. These results show that it is possible to use these composites to detect and/or fracture in structural materials, which are required to monitor the healthiness or safety in industrial applications and public constructions.

• International Journal of Aeronautical and Space Sciences
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• 제7권2호
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• pp.33-41
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• 2006

Theoretical-numerical approach of combustion instability in a specific rocket engine is conducted with parametric response functions. Fluctuating instantaneous burning rate is assumed to be functionally coupled with acoustic pressures and have a finite or time-varying amplitudes and phase lags. Only when the amplitudes and phases of combustion response function are sufficiently large and small respectively, the triggered unstable waves are amplified.

• 한국기후변화학회지
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• 제34권20호
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• pp.8257-8271
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• 2021

This study presents the ability of seasonal forecast models to represent the observed midlatitude teleconnection associated with El Niño-Southern Oscillation (ENSO) events over the North American region for the winter months of December, January, and February. Further, the impacts of the associated errors on regional forecast performance for winter temperatures are evaluated, with a focus on 1-month-lead-time forecasts. In most models, there exists a strong linear relationship of temperature anomalies with ENSO, and, thus, a clear anomaly sign separation between both ENSO phases persists throughout the winter, whereas linear relationships are weak in observations. This leads to a difference in the temperature forecast performance between the two ENSO phases. Forecast verification scores show that the winter-season warming events during El Niño in northern North America are more correctly forecast in the models than the cooling events during La Niña and that the winter-season cooling events during El Niño in southern North America are also more correctly forecast in the models than warming events during La Niña. One possible reason for this result is that the remote atmospheric teleconnection pattern in the models is almost linear or symmetric between the El Niño and La Niña phases. The strong linear atmospheric teleconnection appears to be associated with the models' failure in simulating the westward shift of the tropical Pacific Ocean rainfall response for the La Niña phase as compared with that for the El Niño phase, which is attributed to the warmer central tropical Pacific in the models. This study highlights that understanding how the predictive performance of climate models varies according to El Niño or La Niña phases is very important when utilizing predictive information from seasonal forecast models.

• Nuclear Engineering and Technology
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• 제48권2호
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• pp.495-504
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• 2016

International standards recommend typical phases to be included within any national program for the development of a geological repository dedicated to disposal of the high level radioactive wastes generated in countries using nuclear power. However, these are not universally applicable and the content of each of these phases may need to be adapted for each national situation and regulatory and institutional framework. Several national geological repository programs have faced failures in schedules and have revised their programs to consider an adapted phased management approach. The authors have observed that in the case of those countries in the early phases of a geological repository program where boundary conditions have not been fully defined, international recommendations for handling delays/failures in the national program might not immediately help. This paper considers a case study of the influences of the national context risks on the current planning schedule of the Romanian national geological repository. It proposes an optimum solution for an integrated response to any significant adverse impact arising from these risks, enabling sustainable program planning.

• 한국진공학회:학술대회논문집
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• 한국진공학회 2016년도 제50회 동계 정기학술대회 초록집
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• pp.361.1-361.1
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• 2016

Due to their high sensitivity, fast response, small energy consumption and ease of integration, nanoelectromechanical systems (NEMS) have attracted much interest in various applications such as high speed memory devices, energy harvesting devices, frequency tunable RF receivers, and ultra sensitive mass sensors. Since the device performance of NEMS is closely related with the mechanical and flexural properties of the material in NEMS, analysis of the mechanical and flexural properties such as intrinsic tensile stress and Young's modulus is a crucial factor for designing the NEMS structures. In the present work, the intrinsic mechanical properties of highly stressed silicon nitride (SiN) beams are investigated as a function of the beam length using two different techniques: (i) dynamic flexural measurement using optical interferometry and (ii) quasi-static flexural measurement using atomic force microscopy. The reliability of the results is analysed by comparing the results from the two different measurement techniques. In addition, the mass density, Young's modulus and internal stress of the SiN beams are estimated by combining the techniques, and the prospect of SiN based NEMS for application in high sensitive mass sensors is discussed.