• Earthquakes and Structures
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• 제8권3호
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• pp.665-679
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• 2015

The strain rate of reinforced concrete (RC) structures stimulated by earthquake action has been generally recognized as in the range from $10^{-4}/s$ to $10^{-1}/s$. Because both concrete and steel reinforcement are rate-sensitive materials, the RC beam-column joints are bound to behave differently under different strain rates. This paper describes an investigation of seismic behavior of RC beam-column joints which are subjected to large cyclic displacements on the beam ends with three loading velocities, i.e., 0.4 mm/s, 4 mm/s and 40 mm/s respectively. The levels of strain rate on the joint core region are correspondingly estimated to be $10^{-5}/s$, $10^{-4}/s$, and $10^{-2}/s$. It is aimed to better understand the effect of strain rates on seismic behavior of beam-column joints, such as the carrying capacity and failure modes as well as the energy dissipation. From the experiments, it is observed that with the increase of loading velocity or strain rate, damage in the joint core region decreases but damage in the plastic hinge regions of adjacent beams increases. The energy absorbed in the hysteresis loops under higher loading velocity is larger than that under quasi-static loading. It is also found that the yielding load of the joint is almost independent of the loading velocity, and there is a marginal increase of the ultimate carrying capacity when the loading velocity is increased for the ranges studied in this work. However, under higher loading velocity the residual carrying capacity after peak load drops more rapidly. Additionally, the axial compression ratio has little effect on the shear carrying capacity of the beam-column joints, but with the increase of loading velocity, the crack width of concrete in the joint zone becomes narrower. The shear carrying capacity of the joint at higher loading velocity is higher than that calculated with the quasi-static method proposed by the design code. When the dynamic strengths of materials, i.e., concrete and reinforcement, are directly substituted into the design model of current code, it tends to be insufficiently safe.

• 대한약침학회지
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• 제26권1호
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• pp.18-26
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• 2023

Objectives: Terminalia chebula, the main ingredient of Altan Arur 5, has been used for many years in traditional medicine. This medicine is more effective than other drugs and is used to treat chronic gastritis and gastrointestinal disorders such as peptic ulcers and esophageal reflux. Other ingredients of Altan Arur 5 are Punica granatum (pomegranate), tulip seeds, black balm, and excreta of Trogopterus xanthipes. The main ingredients of T. chebula are antibacterial and analgesic in traditional medicine. Despite having been used for many years and although many studies have been conducted on the beneficial effects of this medicine and its ingredients, the toxicity of Altan Arur 5 has not yet been elucidated. Therefore, we aimed to study the toxicity of Altan Arur 5 to ensure that it is safe to use. Methods: Acute and chronic toxicity of Altan Arur 5 were assessed in 10 Kunming mice and 8 Sprague-Dawley rats, respectively, in different doses. In the acute toxicity study, Altan Arur 5 was orally administered to Kunming mice in doses of 12 g/kg, 24 g/kg, and 48 g/kg for 14 days. In the chronic toxicity study, it was orally administered to Sprague-Dawley rats in doses of 1.25 g/kg, 2.5 g/kg, and 5 g/kg for 12 weeks. Results: No significant differences were observed in the relative organ weights for mice treated with Altan Arur 5 compared with those in the control group. Furthermore, no macro- or microstructural changes were noted in the organs of any group. Conclusion: Our toxicity testing revealed that the traditional medicine Altan Arur 5 has no toxic effects in vivo.

• 문화기술의 융합
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• 제9권6호
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• pp.97-103
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• 2023

이 연구는 노인의 야간보행 불안감에 영향을 미치는 요인을 탐색적으로 살펴보는데 목적이 있다. 분석에 사용된 표본은 65세 이상 노인 9,120명이다. 노인의 야간보행 불안감에 영향을 미치는 요인은 인구사회학적 요인, 건강관련 요인, 그리고 사회적 인식 요인으로 구성되었다. 인구사회학적 요인은 성별, 연령, 지역, 교육수준, 배우자 유무, 가구소득을 포함한다. 건강 관련 요인은 보행능력, 시력, 주관적 건강상태, 인지기능을 포함한다. 사회적 인식 요인은 타인의 준법수준 인식과 범죄에 대한 안전인식을 포함한다. 주요 분석결과는 다음과 같다. 인구사회학적 요인 중 노인의 야간보행 불안감에 유의미한 영향을 미친 변수는 성별, 연령, 지역, 교육수준으로 나타났다. 건강 관련 요인 중 노인의 야간보행 불안감에 유의미한 영향을 미친 변수는 보행능력, 시력, 주관적 건강상태, 인지기능으로 나타났다. 사회적 인식 요인 중 노인의 야간보행 불안감에 유의미한 영향을 미친 변수는 타인의 준법수준 인식과 범죄에 대한 안전인식으로 나타났다. 본 연구의 결과는 노인을 위한 안전하고 편안한 보행환경을 조성하기 위한 다각적인 방안들이 필요함을 보여준다

• 농업과학연구
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• 제39권1호
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• pp.97-110
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• 2012

This study was carried out for safety evaluation, the practical application and improvement of design method of the agricultural reservoir embankment according to backside extension. Seepage analysis, slope stability analysis and finite element analysis were performed for steady state and transient conditions. Also, the pore water pressure, seepage quantity, safety factor and stress-strain behavior according to high water level and rapid drawdown were compared and analyzed. The pore water pressure at contact region between backside extension and old embankment was kept high after rapid drawdown. Therefore, backside extension is recommended that design method is required to be improved and reinforced more than the others raising embankment. The hydraulic gradients before and after backside extension showed high value at the base of the core, but they showed stable state at the upstream slope and downstream slope. The seepage quantity per 1 day and the leakage per 100 m for the steady state and transient conditions appeared to be safe against the piping. The safety factor of slope stability showed high at the steady state, and transient conditions did not show differences depending on the rapid drawdown. The safety factor was appeared high at the upstream slope before backside extension and downstream slope after extension. The excess pore water pressure for steady state and transient conditions showed negative(-) at the upstream slope, it was small at the downstream slope. The mean effective stress (p') showed high at the base of the core and to be wild distribution after the extension. The displacement after extension showed 0.02-0.06 m in the upstream slope, the maximum shear strain after extension was smaller than that before extension.

• 한국지리정보학회지
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• 제17권1호
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• pp.13-23
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• 2014

우리나라는 그간 화산 재해로부터 안전한 지역으로 알려졌다. 그러나, 최근 백두산의 화산 분화 전조현상 들이 자주 보고되고 있으며, 이에 따라 한반도의 화산 분화를 경고하는 화산 전문가들이 늘어나고 있는 실정이다. 본 논문은 백두산 화산 재해 대응 시스템의 개발방안을 기술하고 있다. 첫 번째로 소방방재청의 방재업무 체계와 관련 시스템을 분석한다. 두 번째로, 방재업무체계를 기반으로 화산 재해 대응 업무 프로세스를 도출한다. 세 번째로, 관련 재난 대응 시스템을 참고하여 화산재해 대응시스템의 시스템 아키텍처를 설계하고 필요 공간정보를 도출한다. 마지막으로, 본 논문에서 제안한 화산재해 대응시스템을 테스트하기 위하여 파일럿 시스템을 개발한다. 제안된 화산재해 대응시스템이 실제로 소방방재청에 탑재되기까지는 추가적인 검증 및 시스템 보완이 필요할 것이다. 본 연구를 기반으로 한 완성된 화산재해 대응 시스템은 우리나라와, 중국, 일본의 화산재해로 인한 피해를 최소화 할 것으로 기대된다.

• 의료ㆍ복지 건축 : 한국의료복지건축학회 논문집
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• 제11권2호
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• pp.73-81
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• 2005

The disabled has remarkable difficulties to participate social activities and those, that block them up from access to public facilities and the comfortable habitation so they should get help from others, are mainly made by architectural facts. Buildings without impediment which consider the disabled would be the things responding to the needs of the times. If the disabled would be convenient to use facilities, there should be no difficulties to normal people. A first began to examine into the role of the architecture. And to establish radical standards for the disabled to use cultural and assembly facilities through scrutinizing facilities to get access for the disabled and movement circulations in the cultural facilities should be the conclusion. This study which is a kind of fundamental study to construct cultural facilities without obstacles for the disabled began from consideration for the problem flow line of the disabled in cultural facilities and analyzed flow lines for them to use, access, and evacuate from those which are main facilities in the region. Though, evacuation rules in cultural and assembly facilities are recommendatory in existing laws for convenience of the disabled, the congestion of the crowd coming out after performances impedes safe flows of both the disabled and crowds. Further, in case of evacuation, there would be more serious problems. Therefore, consideration of reinforcement for existing laws for convenience of the disabled is needed.

• 한국항행학회논문지
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• 제24권3호
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• pp.238-244
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• 2020

스마트 시대를 살아가는 요즘 스마트폰을 전 국민이 사용하는 상황으로 봐도 무방할 정도로 빠른 발전과 보급이 진행되었으며, 스마트폰 사용으로 국내 미디어 콘텐츠 이용을 위한 필수 매체로 자리 잡아 성별, 연령, 지역 등에 상관없이 수많은 사람이 다양한 콘텐츠를 이용하고 있다. 최근 다양한 매체를 통해 온라인에서 학습을 위한 동영상 콘텐츠 소비가 이루어지고 있으며, 이는 학습자들이 온라인에서 동영상 콘텐츠를 활용하여 학습에 활용한다는 것을 알 수 있다. 기존 연구에서는 콘텐츠 유형에 따른 만족도 연구를 진행하였으며, 학습 콘텐츠 자체를 평가하여 학습자들에게 제공하는 방법에 대한 연구가 이루어 지지 않아 개선 방안이 필요하다고 판단하였다. 본 논문에서는 학습을 위한 동영상 콘텐츠 제공 방식 동향과 양질의 학습 콘텐츠를 제공하기 위한 개선 방안으로 학습 콘텐츠 자체의 평가와 리뷰를 통해 시스템을 제안하려고 한다.

• Asian Pacific Journal of Cancer Prevention
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• 제16권5호
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• pp.1897-1900
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• 2015

Purpose: To evaluate acute toxicity in nasopharyngeal cancer (NPC) patients treated with intensity modulated radiotherapy (IMRT)/volumetric modulated arc therapy (VMAT) with or without cisplatin-based chemotherapy. Materials and Methods: A total of 45 newly diagnosed, histologically proven non-metastatic NPC patients treated with IMRT between May 2010 and December 2012, were evaluated retrospectively, 37 planned with Eclipse and 8 with Prowess Panther treatment planning system. The doses to the planning target volumes of primary tumor and involved lymph nodes, high risk region, and uninvolved regional nodal areas were 70 Gy, 60 Gy, and 54 Gy respectively and delivered simultaneously over 33 fractions to 39 patients. Another 6 patients irradiated with sequential boost technique. Some 84.4% of patients received chemotherapy. Acute toxicities were graded according to the Radiation Therapy Oncology Group scoring criteria and Common Terminology Criteria for Adverse Events (CTCAE) for chemotherapy side effects. Results: Median age was 43 years (14-79) and all patients were WHO type II. Grade 1 mucositis and dysphagia were observed in 17 (37.8%), and 10 (22.2%) patients, respectively. The incidence of acute grade 2 mucositis and dysphagia was 55.6% and 68.9%, respectively. The most common chemoradiotherapy related acute toxicities were nausea, leucopenia and thrombocytopenia. Grade 3 toxicity was detected in 13 (28.8%) cases. No grade 4 toxicity was occurred. Mean weight loss was 9%. None of the patients required the insertion of percutaneous endoscopic gastrostomy for nutritional support. Radiation therapy was completed without interruption in all patients. Conclusions: IMRT is a safe and effective treatment modality, and well tolerated by patients in the treatment of nasopharyngeal carcinoma. No unexpected side effects were observed.

• 대한인간공학회지
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• 제36권1호
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• pp.37-52
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• 2017

Objective: The present study developed a user-centered 3D virtual liver surgery planning (VLSP) system called Dr. Liver to provide preoperative information for safe and rational surgery. Background: Preoperative 3D VLSP is needed for patients' safety in liver surgery. Existing systems either do not provide functions specialized for liver surgery planning or do not provide functions for cross-check of the accuracy of analysis results. Method: Use scenarios of Dr. Liver were developed through literature review, benchmarking, and interviews with surgeons. User interfaces of Dr. Liver with various user-friendly features (e.g., context-sensitive hotkey menu and 3D view navigation box) was designed. Novel image processing algorithms (e.g., hybrid semi-automatic algorithm for liver extraction and customized region growing algorithm for vessel extraction) were developed for accurate and efficient liver surgery planning. Usability problems of a preliminary version of Dr. Liver were identified by surgeons and system developers and then design changes were made to resolve the identified usability problems. Results: A usability testing showed that the revised version of Dr. Liver achieved a high level of satisfaction ($6.1{\pm}0.8$ out of 7) and an acceptable time efficiency ($26.7{\pm}0.9 min$) in liver surgery planning. Conclusion: Involvement of usability testing in system development process from the beginning is useful to identify potential usability problems to improve for shortening system development period and cost. Application: The development and evaluation process of Dr. Liver in this study can be referred in designing a user-centered system.

• Journal of Acupuncture Research
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• 제26권5호
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• pp.19-28
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• 2009

Objectives : We tried to investigate the effects of Panax Ginseng Radix pharmacopuncture and Zizyphi Spinosi Semen pharmacopuncture on human body with the Heart Rate Variability (HRV) in adult man. As well as we tried to investigate how safe Panax Ginseng Radix and Zizyphi Spinosi Semen pharmacopuncture on the the human being. Methods : We investigated on 44 healthy volunteers consisted of 16 subjects in Panax Ginseng Radix pharmacopuncture group, 13 subjects in Zizyphi Spinosi Semen pharmacopuncture group and 15 subjects in Normal Saline. We ruled out subjects who wasn't stable by rest, with in the limit of normal heart beat(60-120cycle/min). Study form was a randomized, clinical trial. Each group was injected Panax Ginseng Radix pharmacopuncture, Zizyphi Spinosi Semen pharmacopuncture and Normal Saline $0.2m{\ell}$ at $GB_{21}$(Kyonjong). We measured HRV on 7 times : before and after injection per 5 minutes during 30 minutes. The SPSS 13.0 for windows was used to analyze the data by the paired t-test(in the group) and Anova test(among the groups) were used to verify the result. Results : 1. After Panax Ginseng Radix pharmacopuncture injection, SDNN was significantly high, pNN50 was significantly low, Ln(TP) was significantly high, Ln(VLF) was significantly high, Ln(LF) was significantly high at 30 minutes. 2. After Zizyphi Spinosi Semen pharmacopuncture injection, Complexity was significantly low, Ln(VLF) was significantly high at 30 minutes. 3. HRV-index made a significant difference between the Zizyphi Spinosi Semen pharmacopuncture and normal saline at 5 minutes(p=0.02). 4. There wasn's any pain the injected region and whole body, rubefaction, uredo, nausea, vomiting, colic, headache, dizziness within 24 hours. Measured data and mean value of Mean-HRV was within normal range. Conclusions : The results suggested that and Panax Ginseng Radix pharmacopuncture in healthy adult man tended to activate the vagus nervous system within normal range.