• The Journal of Korean Physical Therapy
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• 제21권3호
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• pp.1-8
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• 2009

Purpose: The purpose of this study was to examine the functional category, the item structure and the model-data fit of the neck disability index (NDI) of neck pain subjects by performing a Rasch rating scale analysis. Methods: The data was obtained from the assessments of 71 college students (males: 27, females: 44) with neck pain. The data of the NDI was applied to the Rasch's rating scale model to estimate the difficulty of items, the goodness-of-fit of each item, the separation reliability and index, and the rating scale. Results: The 'sleep' item showed misfit and nine items were founds to be fits for self-reporting of disability due to neck pain. The most difficult item of the remaining 9 items was 'work' and the easiest item was 'headache'. The transformation formula score=(logit score+7.10)/(7.10+0.11)$\times$100. The 6 response levels of the NDI were validated according to the structure of the rating scale. The item and subject reliability of the separation reliability was 0.97 and 0.85, respectively. Conclusion: We proved that the NDI for self-reporting of disability of daily activities due to mild neck pain was valid and reliable. This study suggests that individuals with mild neck pain may be assessed by using the modified NDI that does not include the 'sleep' item in the 10 items of NDI.

• International Journal of Concrete Structures and Materials
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• 제9권1호
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• pp.89-118
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• 2015

The geometric nonlinearity of off-diagonal bracing system (ODBS) could be a complementary system to covering and extending the nonlinearity of reinforced concrete material. Finite element modeling is performed for flexural frame, x-braced frame and the ODBS braced frame system at the initial phase. Then the different models are investigated along various analyses. According to the experimental results of flexural and x-braced frame, the verification is done. Analytical assessments are performed in according to three dimensional finite element modeling. Nonlinear static analysis is considered to obtain performance level and seismic behaviour, and then the response modification factors calculated from each model's pushover curve. In the next phase, the evaluation of cracks observed in the finite element models, especially for RC members of all three systems is performed. The finite element assessment is performed on engendered cracks in ODBS braced frame for various time steps. The nonlinear dynamic time history analysis accomplished in different stories models for three records of Elcentro, Naghan and Tabas earthquake accelerograms. Dynamic analysis is performed after scaling accelerogram on each type of flexural frame, x-braced frame and ODBS braced frame one by one. The base-point on RC frame is considered to investigate proportional displacement under each record. Hysteresis curves are assessed along continuing this study. The equivalent viscous damping for ODBS system is estimated in according to references. Results in each section show the ODBS system has an acceptable seismic behaviour and their conclusions have been converged when the ODBS system is utilized in reinforced concrete frame.

• 한국가스학회지
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• 제18권2호
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• pp.55-61
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• 2014

본 연구는 고무 화학제품의 제조에 연화제로 많이 사용되며 국제암연구소(IARC)에 발암추정물질(2A)로 등록되어 있는 Biphenyl에 대해 국내 취급사업장에 대한 작업환경 측정과 근로자 노출량 산출, 그리고 유해성에 따른 위험성을 결정하였다. 노출시나리오를 바탕으로 노출량 산출 결과는 각각 $1.0{\times}10^{-2}$, $4.2{\times}10^{-4}$, $7.0{\times}10^{-6}mg/m^3$이었으며, 위해성 분류에 따라 산출한 $RfC_{work}$는 발암성 0.21, 표적독성(경구) 2.13, 표적독성(흡입) 0.53, 발달독성 $0.31mg/m^3$으로 산출되었다. 유해성 및 노출평가의 결과를 바탕으로 한 위험성은 발암성 0.57, 비발암성(발달독성) 0.39로 도출되어, 1이하의 비교적 낮은 위험도로 나타났으나, Biphenyl은 일부 유해성이 확인되었으며 사용량이 많고 취급 부주의시 근로자에 직접 노출될 수 있어 취급근로자의 건강장해 예방을 위해 노출 감시가 필요한 물질로 판단되었다.

• 한국수자원학회논문집
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• 제41권9호
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• pp.907-917
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• 2008

본 연구에서는 PRMS, SLURP, SWAT 모형을 이용하여 유출모형에 따라 수자원의 기후변화 영향평가 결과에서 발생할 수 있는 차이를 평가하였다. 이를 위해 먼저 각 모형을 안동댐유역에 적용하여 관측자료에 대한 모의능력을 비교하였다. 그 다음 기온과 강수 변화를 가정한 합성시나리오 상황에서 각 모형별 모의결과를 비교하였다. 분석결과 세 모형은 관측기간에 대해서는 관측유량에 근접한 모의를 하였다. 그러나 강수와 기온의 변화를 고려하였을 경우에는 유출량의 변화량 모의에서 각 모형별로 상이한 결과를 보였다. 특히 기온이 크게 증가할 경우 모형별 결과차이가 증가하는 것으로 분석되었는데, 이것은 각 모델에서 이용하는 증발산량 추정방법의 차이가 가장 크게 영향을 미치는 것으로 분석되었다. 따라서 이러한 불확실성을 고려한 수자원 영향평가 방법이 필요할 것으로 판단되었다.

• 한국실천공학교육학회논문지
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• 제2권2호
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• pp.74-82
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• 2010

진동학은 움직이는 기계 구조물의 설계에 기본이 되는 학문으로 진동 절연, 흡수 등에 관한 방법론과 현장에서 발생하는 다양한 진동문제에 대한 해석 수행 능력을 배우는 학문이다. 하지만 진동학은 기계공학에서 다른 역학과목들에 비해 이해하기 어려운 교과목이기 때문에 진동학 이론의 물리적인 이해를 돕기 위해 진동학 관련 교육장비 개발이 매우 필요한 상황이다. 이에 본 논문에서는 진동학의 이론적인 내용을 실험을 통하여 학생들이 보다 쉽게 진동학의 물리적인 의미를 깨달을 수 있도록 도와주는, 그리고 실험과정이 간단한 교육용 복합 진동실험장치를 개발하고 그 적용효과를 알아보고자 한다. 다자유도 진동, 보 진동, 현 진동 및 판 진동의 4가지 대표적인 진동현상을 실험할 수 있는 복합 진동실험 장치를 개발하고 적용범위를 제시한다. 마지막으로 설문조사를 통하여 학업성취 반응도평가 및 개선방안을 제안한다.

• Archives of Plastic Surgery
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• 제36권1호
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• pp.38-45
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• 2009

Purpose: The congenital muscular torticollis is a neck deformity involving shortening of the sternocleidomastoid muscle, which is detected at birth or shortly after birth. This childhood disease is the third most common congenital musculoskeletal anomaly. The indication for surgery is a persistent head tilt with dificit of passive rotation and lateral bending of the neck and a tight band or tumor in the sternocleidomastoid muscle even after physical therapy. The purpose of this article is to report surgical outcomes with patients who had no or little response to physical therapy. Methods: Surgery was performed on 29 patients and their average age was 4.1 years (from 6 months to 20.1 years). The unipolar open release and partial myectomy were done in 28 cases and the muscle lengthening was done in 1 case. Physical therapy was started from postoperative seventh day. Follow - up period was ranged from 2 months to 5.4 years(mean follow - up, 20.4 months). Result: There were neither rotation nor lateral bending deficit after surgical treatment. Mild head tilt was noticed in 3 cases and residual bend was observed in 4 cases. The subjective assessments of surgical results by parents were excellent. Conclusion: Our surgical outcome encourages the surgical treatment of congenital muscular torticollis for patients who failed to respond to physical therapy.

• Earthquakes and Structures
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• 제18권2호
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• pp.147-162
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• 2020

This paper presents a novel precast energy dissipation shear wall (PEDSW) structure system that using mild steel dampers as dry connectors at the vertical joints to connect adjacent wall panels. Analytical studies are systematically conducted to investigate the seismic performance of the proposed PEDSW under sequence-type ground motions. During earthquake events, earthquake sequences have the potential to cause severe damage to structures and threaten life safety. To date, the damage probability of engineering structures under earthquake sequence has not been included in structural design codes. In this study, numerical simulations on single-story PEDSW are carried out to validate the feasibility and reliability of using mild steel dampers to connect the precast shear walls. The seismic responses of the PEDSW and cast-in-place shear wall (CIPSW) are comparatively studied based on nonlinear time-history analyses, and the effectiveness of the proposed high-rise PEDSW is demonstrated. Next, the foreshock-mainshock-aftershock type earthquake sequences are constructed, and the seismic response and fragility curves of the PEDSW under single mainshock and earthquake sequences are analyzed and compared. Finally, the fragility analysis of PEDSW structure under earthquake sequences is performed. The influences of scaling factor of the aftershocks (foreshocks) to the mainshocks on the fragility of the PEDSW structure under different damage states are investigated. The numerical results reveal that neglecting the effect of earthquake sequence can lead to underestimated seismic responses and fragilities, which may result in unsafe design schemes of PEDSW structures.

• 자원ㆍ환경경제연구
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• 제16권3호
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• pp.653-682
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• 2007

In this study, multi-sectoral partial equilibrium and computable general equilibrium models of Taiwan are used to investigate the direct and indirect effects of energy price increases on overall economies and agro-food sector in Taiwan. The results suggest that agricultural prices, production cost would increase between 0.27% to 1.88%, and a reduction in GDP around 0.39% to 0.54 %. The negative impact on livestock sector is slightly higher than that on the crop sector. Negative impacts are also observed in the employment and wages. The rising oil price has the potential to discourage production of energy-intensive activity because of the possibility of substitution and adaptations. The growth rate of real GDP will shrink by 0.64% to 1.06% and CPI will increase by 1.17% to 1,95%. Both the agriculture and non-agricultural sector also respond by raising output prices by 0.80% to 1.33%. The rising international oil price has urged the government to take policy actions like using alternative fuels such as biodiesel, bioethanol, and adopting measures to cut down on energy consumptions mainly in transportation sectors in response to public concern over economic shocks.

• 한국방재학회 논문집
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• 제9권2호
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• pp.31-37
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• 2009

우리나라는 매년 풍수해에 의한 피해가 증가하고 있으며, 대부분의 피해가 하천, 도로시설물을 중심으로 주로 일어나고 있다. 이들 피해에 따른 국가복구지원의 문제점은 매년 많은 금액의 피해 복구비가 투입되었음에도 불구하고, 개선복구 보다는 원상복구 위주의 복구비 지원으로 반복적 피해가 발생하고 있다는 사실이다. 이러한 재난의 비효율적 반복피해를 예방하기 위해서는 자연재난으로 인한 피해의 원인을 보다 정확히 진단하고 항구적인 방어대책의 마련을 위한 보다 구체적인 기준이 필요하다. 본 연구에서는 최근 국내에서 발생하고 있는 풍수해에 대한 전반적인 실태조사를 통하여 피해현상의 유형별 구분과 분석을 각각의 피해에 대한 복구방법이나 대책방법으로 각각 체계적으로 다르게 분류하고 보다 선진화된 예방적 복구 개념을 도입하기 위하여 피해 유형별로 새롭게 정리하였다. 이를 통하여 피해유형에 따른 피해분류 및 피해사례를 보다 체계적으로 수립, 계획할 수 있는 유형화 도감 및 평가방법을 국내외 수많은 기 선행 개선복구 사례를 토대로 분류, 개발하였다.

• Journal of Oral Medicine and Pain
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• 제45권2호
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• pp.23-28
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• 2020

Purpose: Temporomadibular disorders (TMDs) can result in chronic pain, which is often associated with psychological and sleep disturbance. Increased levels of psychological and sleep impairments are often related with poor treatment outcomes. The purpose of the present study was to evaluate clinical features, psychological profiles and the prevalence of clinical insomnia in TMD patients with chronic pain and to suggest an effective treatment approach. Methods: A total of 200 TMD patients who had visited the Pusan National University Hospital dental clinic for treatment of their pain were recruited from June 2018 through December 2019. TMD patients were classified into an acute (n=100) and chronic (n=100) group and compared the clinical symptoms. The primary diagnosis of TMD were categorized as TMD with joint pain group (TMD_J), TMD with muscle pain group (TMD_M) and TMD with joint-muscle mixed pain group (TMD_JM). Self- report measures of sleep quality and psychological profiles were evaluated via the Insomnia Severity Index (ISI) and the Korean Stress Response Inventory (SRI). Independent t-tests, Mann-Whitney U-tests, and chisquared test were used for the statistical analysis. Results: Chronic TMD patients showed higher pain intensity, as well as higher prevalence of related symptoms (headache, musculoskeletal pain) and myogenous pain. They also had significantly higher scores in all SRI parameters and a higher percentage of clinical insomnia than acute TMD patients. Conclusions: Based on the above results, psychological profiles and sleep quality assessments are necessary to provide essential data that will allow for improved treatment of chronic TMD patients.