• 제목/요약/키워드: Level Set method

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터널 내 콘크리트포장 표면처리공법 별 탑승자의 주행쾌적성 평가 (Evaluation on Riding comfort of A Passenger with Various Surface Textures of Concrete Pavement in Tunnels)

  • 이경배;이재훈;손덕수;권순민
    • 한국도로학회논문집
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    • 제16권5호
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    • pp.155-164
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    • 2014
  • PURPOSES : The purpose of this article is to compare and evaluate the riding comfort of a passenger in tunnels depending on different surface textures of concrete pavement. METHODS : Evaluation of riding comfort is conducted at 17 sections, which have different surface texture such as transverse tinned(TT), longitudinal tinned(LT) and diamond grinded(DG). A triaxial accelerometer was set up on the passenger seat surface of the test vehicle to measure vibrations of an occupant, then the effects of vibration on comfort and health were evaluated by ISO 2631. And microphones were installed at passenger's ears height to measure sound pressure level(SPL) in the test vehicle. Additionally, a surface microphone was installed on the inside of wheel arch to evaluate noise between tire and pavement by NCPX method. All tests were conducted cruising at 100km/h. RESULTS : The results of all tests are as follows. First, both vibration magnitudes for comfort and for health in LT and DG sections are almost same and they represent lower than those in TT sections. Second, the average SPL of DG shows the lowest decibels among them. And third, it is founded that interior noise is significantly affected by noise between tire and pavement. CONCLUSIONS : It may be concluded that DG can provide more excellent riding comfort to passenger than LT or TT. Therefore, it is necessary to consider applying DG to existing pavement surface to improve surface condition when the driving environment especially requires riding comfort like a long tunnel.

교량에 부착된 도시가스 배관의 응력에 관한 연구 (A Study of Stress off City Gas Pipe Attached on the Bridge)

  • 이수경;임봉관
    • 한국가스학회지
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    • 제10권3호
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    • pp.20-26
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    • 2006
  • 본 연구에서는 교량에 부착된 도시가스 배관 53개소에 대해 현장조사를 실시하고 위해요인이 발생할 우려가 있는 도시가스배관 대해 구조해석 프로그램을 이용한 응력분석을 실시하고 취약부위에 대한 현장 응력 측정을 통해 배관에 미치는 응력에 관한분석을 실시하여 가스배관의 안전성을 평가하고자 했다. 현장 안전진단의 결과는 일차적으로 선정된 대상 10개소 중 가장 응력적으로 취약할 것으로 판단되는 2개소에 대해 현장 응력측정을 통한 진단을 수행하였다. 안전계수 2를 고려한 배관 최대 지지응력의 70% 이상 수준의 응력이 부가되는 것으로 나타났다. 보수시점을 넘어선 교량첨가배관에 대해 응력 해소 공사, 지지대 보수 및 교체 공사를 통해 부가되는 응력을 해소하였다. 현장진단 결과로 나타난 바와 같이 장기간 경과된 배관에서도 견고한 고전으로 발생하는 응력은 보수를 통하여 해소해줌으로 안전성을 확보할 수 있었다.

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소프트에러 결함 허용 캐쉬 (Fault Tolerant Cache for Soft Error)

  • 이종호;조준동;표정열;박기호
    • 전기학회논문지
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    • 제57권1호
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    • pp.128-136
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    • 2008
  • In this paper, we propose a new cache structure for effective error correction of soft error. We added check bit and SEEB(soft error evaluation block) to evaluate the status of cache line. The SEEB stores result of parity check into the two-bit shit register and set the check bit to '1' when parity check fails twice in the same cache line. In this case the line where parity check fails twice is treated as a vulnerable to soft error. When the data is filled into the cache, the new replacement algorithm is suggested that it can only use the valid block determined by SEEB. This structure prohibits the vulnerable line from being used and contributes to efficient use of cache by the reuse of line where parity check fails only once can be reused. We tried to minimize the side effect of the proposed cache and the experimental results, using SPEC2000 benchmark, showed 3% degradation in hit rate, 15% timing overhead because of parity logic and 2.7% area overhead. But it can be considered as trivial for SEEB because almost tolerant design inevitably adopt this parity method even if there are some overhead. And if only parity logic is used then it can have $5%{\sim}10%$ advantage than ECC logic. By using this proposed cache, the system will be protected from the threat of soft error in cache and the hit rate can be maintained to the level without soft error in the cache.

외부 유동에 의한 흡차음재 공간내의 소음 예측 (Predicting Noise inside a Trimmed Cavity Due to Exterior Flow)

  • 정찬희;;최의성;조문환
    • 한국소음진동공학회:학술대회논문집
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    • 한국소음진동공학회 2014년도 춘계학술대회 논문집
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    • pp.466-471
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    • 2014
  • The interior vehicle noise due to the exterior aerodynamic field is an important topic in the acoustic design of a car. The air flow detached from the A-pillar and impacting the side windows are of particular interest as they are located close to the driver / passenger and provides a lower insulation index than the trimmed car body parts. This paper presents a numerical analysis method for a simplified vehicle model. The internal air cavity including trim component are included in the simulation. The car body includes the windshield and two side windows. The body is made of aluminum and trimmed with porous layers. The methodology proposed in this paper relies on two steps: the first step involves the computation of the exterior flow and turbulence induced non-linear acoustic field using PowerFlow. The second step consists in the computation of the vibro-acoustic transmission through the window using the finite element vibro-acoustic solver Actran. Additionally in order to validate the numerical process, an experimental set-up has been created based on the simplified vehicle. The vibration of the windshield and windows, the total wind noise level results and the relative contributions of the different windows are then presented and compared to measurements. The influence of the flow yaw angle (different wind orientation) is also assessed.

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Photogrammetric Analysis of Attractiveness in Indian Faces

  • Duggal, Shveta;Kapoor, DN;Verma, Santosh;Sagar, Mahesh;Lee, Yung-Seop;Moon, Hyoungjin;Rhee, Seung Chul
    • Archives of Plastic Surgery
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    • 제43권2호
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    • pp.160-171
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    • 2016
  • Background The objective of this study was to assess the attractive facial features of the Indian population. We tried to evaluate subjective ratings of facial attractiveness and identify which facial aesthetic subunits were important for facial attractiveness. Methods A cross-sectional study was conducted of 150 samples (referred to as candidates). Frontal photographs were analyzed. An orthodontist, a prosthodontist, an oral surgeon, a dentist, an artist, a photographer and two laymen (estimators) subjectively evaluated candidates' faces using visual analog scale (VAS) scores. As an objective method for facial analysis, we used balanced angular proportional analysis (BAPA). Using SAS 10.1 (SAS Institute Inc.), the Turkey's studentized range test and Pearson correlation analysis were performed to detect between-group differences in VAS scores (Experiment 1), to identify correlations between VAS scores and BAPA scores (Experiment 2), and to analyze the characteristic features of facial attractiveness and gender differences (Experiment 3); the significance level was set at P=0.05. Results Experiment 1 revealed some differences in VAS scores according to professional characteristics. In Experiment 2, BAPA scores were found to behave similarly to subjective ratings of facial beauty, but showed a relatively weak correlation coefficient with the VAS scores. Experiment 3 found that the decisive factors for facial attractiveness were different for men and women. Composite images of attractive Indian male and female faces were constructed. Conclusions Our photogrammetric study, statistical analysis, and average composite faces of an Indian population provide valuable information about subjective perceptions of facial beauty and attractive facial structures in the Indian population.

한국 연안 심해 설계파고의 극치분포 특성 (Characteristics on the Extreme Value Distributions of Deepwater Design ave Heights off the Korean Coast)

  • 정신택;김정대;조홍연
    • 한국해안해양공학회지
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    • 제16권3호
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    • pp.130-141
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    • 2004
  • 연안 및 항만구조물의 설계에서 심해 설계파는 매우 중요한 환경인자이다. 특히, 심해설계파고의 분포 정보는 최근 부각되고 있는 신뢰성 설계에 필수적인 요소이다. 본 연구에서는 한국해양연구원(2003)에서 제시한 1979년부터 1998년까지의 한국연안 67개 지점의 16방향별 최대 유의파 산출자료를 이용하여 극치분포 분석을 수행하였다. 특성분석에 사용된 극치분포함수는 Weibull, Gumbel, Log-Pearson Type-III, Lognormal 분포이며, 각 분포함수의 매개변수는 모멘트법, 최우도법 그리고 확률가중모멘트법으로 추정하였다. 또한, 극치분포함수의 적합성은 95% 신뢰도 수준으로 $\chi$$^2$및 K-S 검정을 실시하였다. 그 결과, 한국연안의 심해 설계파고는 Gumbel 분포형이 가장 적합한 모형으로 파악되었으며, 최적 추정된 매개변수 및 재현기간 50년에 대한 심해 설계파고 정보를 제시하였다.

핵심역량 기반 관점에서의 치위생(학)과 교육목표 분석 (Analysis of the education objectives of the dental hygiene department from core competencies-based perspective)

  • 최규일;이형숙
    • 한국치위생학회지
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    • 제12권5호
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    • pp.1049-1058
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    • 2012
  • Objectives : It will be necessary to make statement about the competence targeted in the dental hygienic education that adopts the competence-based curriculum from the standpoint of core competence which the students need to be equipped with in the society. Methods : To achieve the education objective of Dental Hygienics, the information available on the website of the Korean Dental Association, universities and graduate schools were used, and the education objectives of the concerned universities which were posted in the websites of 82 universities from July to August, 2011 were analyzed. Results : C7 and C1 accounted for 21.1%, the highest percentage, in the core capability, while HP1 comprised 79.6% in the health improvement and disease prevention. CM1 stood at 73.7%, the highest percentage, in the community involvement(CM) area, and PC4 accounted for 90.8%, the highest percentage, in the patient care(PC) area. In the professional growth and development(PGD) area, PGD1 was the highest, followed by PGD3. In relation to the comments on the occupational types after graduation, 63.1% of respondents mentioned the dental hygienists at the school, while 33.3% did not make any comment on the dental hygienists. Conclusions It was necessary to re-establish the essential objectives of the graduates based on the competence as the accomplishments of studying and learning in the department of dental hygiene. It may be a useful method to set the competency-based education objective on the basis of the implementation ability and the level of graduates.

총요소생산성을 고려한 한국의 CO2 배출량에 대한 EKC 가설 검증: 지역별 CO2 배출량과 GRDP를 중심으로 (EKC Hypothesis Testing for the CO2 Emissions of Korea Considering Total Factor Productivity: Focusing on the CO2 Emissions by Region and GRDP)

  • 김수이;정경화
    • 자원ㆍ환경경제연구
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    • 제23권4호
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    • pp.667-688
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    • 2014
  • 본 연구는 우리나라의 지역별 $CO_2$ 배출량과 지역별 GRDP데이터를 사용하여 EKC(Environment Kuznets Curve)를 검증하였다. 이 분석을 위해서 1990년부터 2010년 기간 동안 우리나라의 15개 광역지방자치단체를 대상으로 한 패널데이터를 구축하였다. 지역별 $CO_2$ 배출량에 영향을 미치는 요인으로는 일인당 GRDP, 인구, 총요소생산성 등을 고려하였다. 그리고 이러한 요인들이 $CO_2$ 배출량에 영향을 미치는데 있어서 역 U자형 가설이 성립하는지를 검증하였다. 본 연구에 사용한 분석 방법은 Lantz and Feng(2006)에서와 마찬가지로 패널 GLS 모델을 사용하였다. 분석결과에 의하면 우리나라의 경우 EKC 가설이 성립하지 않았지만 총요소생산성의 경우에는 $CO_2$ 배출량과 역 U자형 관계가 성립하였다. 본 연구의 의의는 특히 기술 진보를 대변하는 총요소생산성이 증가할수록 $CO_2$ 배출량이 증가하지만 일정수준 이후에는 $CO_2$ 배출량이 감소한다는 것이다.

PBNM과 DiffServ 적용한 3GPP 서비스의 QoS 해석 (QoS Analysis of 3GPP Service based on PBMN and DiffServ)

  • 송복섭;김정호
    • 한국콘텐츠학회논문지
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    • 제11권12호
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    • pp.570-577
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    • 2011
  • 본 논문에서는 3GPP 서비스의 QoS에 정책 기반 망 관리 기법이 적용되지 않고 DiffServ 기술에 적용된 경우를 우선 해석하고, 다음으로 정책 기반 망 관리 기법(PBNM)과 DiffServ 기술이 연계된 경우를 적용하여 QoS 성능개선을 검증한다. PBNM과 DiffServ를 적용했을 때, 출력링크 용량에 75%의 최선형 트래픽이 발생해도 음성 트래픽의 양이 1 msec 정도 줄어들었다. 비디오 트래픽 역시 데이터 트래픽과 같은 취급을 받으므로 DiffServ 때에 비해 패킷 손실율이 줄어들어 0 에서 $10^{-4}$ 정도의 결과를 가져옴을 알 수 있었다. 적합한 정책 PBNM과 DiffServ을 적용하면 기존의 정해진 QoS 메커니즘의 영향을 받지 않고 적합한 정책을 사용하는 것만으로도 3GPP 서비스의 QoS 수준에 맞도록 망을 운영, 관리 할 수 있음을 알 수 있었다. 이에 따른 해석적 방법은 버클리 대학의 NS-2를 통하여 기존 시스템에 의무화된 DiffServ 기술과 차세대 망에서 의무화된 PBNM과 DiffServ 기술이 적용된 경우에 대해 성능평가 한다.

암 환자의 정신사회적 치료 (Psychosocial Management of Cancer Patients)

  • 송지영
    • 정신신체의학
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    • 제2권1호
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    • pp.22-33
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    • 1994
  • The author presented several points of experienced materials obtained from the joint meetings of consultation-liaison Psychiatric division with oncologic department in Kyung Hee University Hospital. The joint meetings which have been held regularly every other week were very helpful not only for the psychiatrist but also for the cancer department stags to manage the cancer patients actively. The joint meetings have been progressed into more cohesive and active communication as time goes by. Most of the subjects discussed in the meeting was focused on the psychological and behavioral problems of the cancer patients. Besides, the difficulties arising from the chemotherapy were discussed. Probably the most difficult task for the treatment team was to provide complete information while respecting the patient's right to deny their situation The liaison psychiatrist usually gave comments to the charge doctor and/or nusing staff how to evaluate the patient's behavior and what would be the influential factors in developing the doctor-patient relationship. It was found that many cancer patients and their family members had their own peculiar illness behavior and disease concept which led patients to take non-medical or moreover, anti-therapeutic care. The family members were found to play an influential role in the choice of treatment method and progression of the disease. Another role of the liaison psychiatrist in the oncology ward was to encourage the treatment team members. In the practical point of view, it was not easy for the liaison psychiatrist to have time regularly for the cancer patients to encourage the liaison activities. And it seems to be fundamental that the consultation fee for the liaison psychiatrist should be set up at the resonable level.

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