• 대한수의학회지
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• 제59권1호
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• pp.17-24
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• 2019

Animal models of osteoarthritis (OA) have played a key role in understanding the etiology of OA and in the development of new therapeutic strategies. Although pigs have an advantage as an animal disease model due to their similarity to humans, there are few studies on the induction of OA in minipigs. Therefore, this study aimed to characterize disease progression of OA in total medial meniscectomy (TMM)-operated skeletally mature minipigs, up to day 180 postoperatively. There were no significant alterations in vital signs or hematological indices throughout the observation period. However, clinical manifestations of OA in the medial femoral condyles of TMM-operated minipigs were progressive, depending on postoperative duration, with respect to osteophytes formation and roughened surfaces on radiological observation, cartilage erosion under macroscopic examination, and severe cartilage defects including fibrillation, vertical fissures, and cartilage denuding on histopathological observation, with the highest score indicating late-stage OA on day 180 and without indicating apparent variation between subjects. In particular, the lateral femoral condyles were also degenerated, possibly due to localization of weight-bearing from both menisci to the lateral meniscus. Therefore, TMM in minipigs is suitable for reproducible induction of degenerative changes in the femorotibial joints that closely resemble late-stage OA, and is suitable for use in further research.

• 대한한의학방제학회지
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• 제31권4호
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• pp.389-413
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• 2023

Objectives : This study aimed to review the current trends in experimental studies on the use of natural products for treatment of gastroesophageal reflux disease (GERD). Methods : Experimental studies assessing the efficacy of natural products against GERD were searched on PubMed. Articles were selected based on predefined inclusion and exclusion criteria and then analyzed for experimental methods, interventions, and result analysis techniques. Results : A total 37 studies were included in this review. Predominantly, in vivo experiments were conducted to induce GERD through surgery, involving the ligation of the pylorus and the transitional junction between the corpus and the forestomach using 7-week-old male Sprague-Dawley rats. The acute induction model, sacrificing animals after a single administration following GERD induction, was mainly used.The utilization of cell experiments was relatively infrequent, with a focus on assessing antioxidant and anti-inflammatory effects via the treatment of the RAW 264.7 cell line with lipopolysaccharides treatment. Glycyrrhizae Radix et Rhizoma, Pinelliae Tuber, Ginseng Radix and Zingiberis Rhizoma were used as single ingredients, and herbal formula, STW-5 (iberogast), Rikkunshito (六君子湯), Banhasasim-tang (半夏瀉心湯), and Hewei Jiangni granule (和胃降逆湯) were used. Outcome analysis methods encompassed Macroscopic evaluation, esophageal function assessment, blood biomarker analysis, histological examination, protein analysis, gene expression analysis, and gastric juice analysis. Proton pump inhibitors were predominantly employed as positive controls. Conclusions : This study revealed the current trends in non-clinical research evaluating natural products for GERD. Based on the results of this study, we expect that non-clinical research on clinically effective natural products will be revitalized.

• 한국과학교육학회지
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• 제26권4호
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• pp.510-517
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• 2006

이 연구에서는 화학 개념 학습에서 학생들에게 제공되는 다양한 외적 표상들 간의 연계와 통합을 촉진하는 방안으로서의 그리기에 미치는 상황 흥미, 주의 집중, 인지적 노력의 영향을 조사하였다. 2개 남녀공학 중학교 1학년 178명을 대상으로 '보일의 법칙'과 '샤를의 법칙'에 대해 2차시 동안 그리기를 활용한 수업을 실시하였다. 학생들은 거시적인 현상을 시범 실험을 통해 관찰한 후, 제공된 언어적 정보에 대한 자신의 정신 모형을 그림으로 그리고 이를 시각적 정보와 비교하였다. 사후 검사로 상황 흥미, 주의집중, 인지적 노력, 개념 이해도 검사를 실시하였다. 연구 결과, 상황 흥미는 주의집중에 직접적인 영향을 주고, 주의집중은 직접적으로 또는 인지적 노력을 경유하여 개념 이해도에 긍정적인 영향을 주는 것으로 나타났다. 이런 결과는 그리기에서 처음으로 유발되는 것은 상황 흥미이며, 주의집중과 인지적 노력이 그리기를 통한 개념 이해에 직접적인 영향을 주는 요인일 수 있음을 시사한다. 이에 대한 교육적 함의를 논의하였다.

• 대한교통학회지
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• 제22권4호
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• pp.147-158
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• 2004

SWP(Stochastic Wave Propagation: 확률파장전파) 모형은 Cellular Automata(CA) 이론을 기반으로한 간략한 차량모형을 이용하여 개별차량의 확률적 형태와 혼잡의 전파를 모사하고, 통계물리학을 기반으로 교통류를 거시적으로 해석한다. SWP모형은 이산적 시공간 구조와 정수형 자료를 이용한 프로그램 지향적 모형구조를 가지며 연산수행속도가 빨라 대규모 가로망의 실시간 시뮬레이션을 가능하게 하였다. 그러나 비현실적인 충돌회피과정으로 인한 자연발생적 혼잡(Spontaneous jam)의 형성 때문에 미시적으로는 혼잡내에서 잠금현상(Lockup)이 발생하여 혼잡내 차량의 저속을 설명할 수 없고, 거시적으로는 혼잡의 밀도와 전파속도를 설명하기 어렵다는 한계를 가지고 있다. 본 연구에서는 비현실적인 차량의 정지과정을 보다 현실적으로 모사하기 위한 정지조작규칙(SMR: Stopping Maneuver Rule)과 혼잡내에서 차량의 낮은 가속을 설명하기 위한 저가속규칙(LAR: Low Acceleration Rule)을 기존의 SWP모형인 NaSch모형에 추가하였다. 이를 통해 미시적으로 보다 현실적인 차량의 정지과정을 모사하면서 혼잡내에서 잠금현상을 방지하고, 거시적으로 혼잡의 밀도와 전파속도를 설명함으로써 보다 다양하게 연속 교통류를 구현하는 모형을 구축하였다.

• 대한교통학회지
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• 제34권2호
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• pp.146-157
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• 2016

본 연구는 Daganzo가 돌발상황 검지를 위해 1997년에 제안한 삼연속 검지기 단순화 해법을 통계적 모형으로 구현하고 이에 대한 통계적 적합성 검증을 목적으로 한다. 본 연구는 삼연속 검지기 단순화 해법의 계산과정을 정리하였으며, 이를 통계 프로그래밍을 활용해 구현하였다. 먼저 진출입부가 존재하지 않는 고속도로 본선의 검지기 자료를 활용하여 본 해법을 적용하였다. 그리고 삼연속 검지기 단순화 해법의 통계적 검정을 위해 충격파에 의한 교통량의 동적 변화를 반영하는 30초 단위 누적교통량을 돌발상황 교통류와 정상 교통류 각각에 대해 추정하고, 실측 누적교통량과의 오차를 통계적으로 비교하였다. 오차검정 결과 돌발상황 검지기법을 통한 누적교통량 추정치는 통계적으로 실측치와 적합성이 높게 나타났으며, 오차 값의 유의성은 사고로 인한 돌발상황 교통류가 정상 교통류에 비해 분산 및 평균이 이질적인 것으로 나타났다. 본 연구는 기존 Newell, Daganzo의 단순화 교통류 모형의 이론적 연구를 돌발상황 검지로 응용 발전시킨 연구이며, 나아가 다양한 도로조건과 돌발상황 유형에서의 실험을 통한 모형 개선을 향후 과제로 한다.

• 터널과지하공간
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• 제26권3호
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• pp.235-252
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• 2016

본 연구에서는 다각형 입자 기반 개별요소모델을 이용하여 실험실 스케일에서 등방성, 횡등방성 암석의 거동과 점진적 파괴 과정을 모델링할 수 있는 시뮬레이션 기법을 구축하였다. 가압에 따른 미세균열의 개시와 성장 과정을 모니터링할 수 있는 기법을 제안하였으며, 이를 통해 전단균열과 인장균열의 개시와 성장이 암석의 점진적 파괴 과정에 미치는 영향을 살펴보았다. 다각형 입자기반 개별요소모델의 거동 및 미세균열의 발생 양상은 실험실에서 관찰되는 암석의 일반적인 특징과 상당 부분 일치하는 것으로 나타났으며, 이를 통해 상기 모델이 암석의 역학적 거동을 합리적인 수준에서 재현할 수 있음을 확인하였다. 다각형 입자기반 개별요소모델에 대한 기초연구로서 접촉면의 미시변수와 시료의 거시물성 간의 상관관계를 살펴보았으며, 미시변수를 조정함으로써 다양한 암석의 강도와 변형 특성을 재현하였다. 한편, 상기 모델을 횡등방성 암석을 모사하기 위한 방법론을 제시하였으며, 이를 국내 횡등방성 암석인 아산편마암에 적용하여 근소한 오차 범위 내에서 실내시험 결과를 재현하였다.

• 성인간호학회지
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• 제23권5호
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• pp.503-513
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• 2011

Purpose: The purpose of this study was to identify a model based on f the learning objectives in adult health nursing curriculums. The model can be eventually reflected in Korean National Nurse's Licensing Examination (KNNLE). Methods: The model was developed through a series of practical analysis by the task force team from June to October, 2011. The research team conducted the data synthesis and analysis from the learning objectives of adult health nursing drawn from selected national and international universities, from the adult health nursing areas in KNNLE, and from the current disease prevalence from clinical data in the representative university hospitals in Korea. Results: The current disease prevalence and mortality rates are on the increase especially for malignant neoplasm, heart diseases, suicide and diabetes. The items on the KNNLE of adult nursing are categorized by body systems into digestive system (15%), introduction (13.8%), respiratory system (11.3%), and cardiac system (11.3%). While the current system-based learning objectives covers extensive areas of adult health nursing, the core items are required to be selected based on core competences and core learning objectives to restructure the items of KNNLE. The first revised model is to consolidate and restructure the items microscopically in the subjects of adult health nursing by system. The second proposed model from macroscopic perspective is to build a comprehensive scheme of nursing curriculum by encompassing 8 subjects under current KNNLE and adjust the number of items accordingly. Conclusion: The items of KNNLE need to be gradually redesigned by considering the intervention need at clinical practice and the modified learning objectives of adult health nursing. Based on the job analysis on core competences for newly employed nurses performed by the Korean Accreditation Board of Nursing, it is necessary to establish the core learning objectives of adult health nursing and set up standards for core items in KNNLE.

• 한방재활의학과학회지
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• 제27권4호
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• pp.33-53
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• 2017

Objectives This study was designed to review animal studies about the efficacy of herbal medicine for Rheumatoid arthritis animal model which was published in Korea after 2008. We also systematically investigated the reporting quality of the animal studies. Methods We systematically searched original articles in 8 databases since 2008. And manual searching was conducted through 10 Korean medicine journals from 2008. Studies were included if they used animal experimental model(s) with orally administered herbal medicine. Data were extracted regarding animal model, rheumatoid arthritis indicator and detail of intervention. Reporting quality of each study was also assessed by the STARA and ARRIVE guidelines. Results Nine hundred two articles were screened. Finally, 35 articles were included. 35 studies all showed that the herbal medicine used in the studies has significant effect on alleviating the macroscopic indicators, hematological indicators, histological indicators, genetic indicators, osteological indicator of Rheumatoid Arthritis and others. Species of animals was reported in 100% while ventilation and noise were reported in 0% in STRASA guidelines. Ethical statement was reported in 42.9%, experimental animals and sample size were reported in 24%, 29% and there was no study reporting funding. Conclusions These results suggest that herbal medicine might be effective treatment for Rheumatoid Arthritis. It should be improved by clinical studies. And there is a need for studying about efficacy and safety of each specific herbal medicine. And we should improve the Reporting quality of the animal studies published in Korea.

• Geomechanics and Engineering
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• 제23권2호
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• pp.139-149
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• 2020

Piles are widely used in structural foundations of engineering projects. However, the deformation of the soil around the pile caused by driving process has an adverse effect on adjacent existing underground buildings. Many previous studies have addressed related problems in sand and saturated clay. Nevertheless, the failure mechanism of pile driving in unsaturated soil remains scarcely reported, and this issue needs to be studied. In this study, a modeling test system based on particle image velocimetry (PIV) was developed for studying deformation characteristics of pile driving in unsaturated silt with different water contents. Meanwhile, a series of direct shear tests and soil-water characteristic curve (SWCC) tests also were conducted. The test results show that the displacement field shows an apparent squeezing effect under the pile end. The installation pressure and displacement field characteristics are sensitive to the water content. The installation pressure is the largest and the total displacement field is the smallest, for specimens compacted at water content of 11.5%. These observations can be reasonably interpreted according to the relevant unsaturated silt theory derived from SWCC tests and direct shear tests. The variation characteristics of the soil displacement field reflect the macroscopic mechanical properties of the soil around the pile.

• Geomechanics and Engineering
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• 제11권2호
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• pp.253-267
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• 2016

The stability of surrounding rock will be poor when the tunnel is excavated through nearly horizontal stratum. In this paper, the instability mechanism of local nearly horizontal stratum in super-large section and deep buried tunnel is revealed by the analysis of the macro failure and micro fracture. A structural model is proposed to explain the mechanics of surrounding rock collapse under the action of stress redistribution and shed light on the macroscopic analytical approach of the stability of surrounding rock. Then, some highly effective formulas applied in the tunnel engineering are developed according to the theory of mixed-mode micro fracture. And well-documented field case is made to demonstrate the effectiveness and accuracy of the proposed analytical methods of mixed-mode fracture. Meanwhile, in order to make the more accurate judgment about yield failure of rock mass, a series of comprehensive failure criteria are formed. In addition, the relationship between the nonlinear failure criterion and $K_I$ and $K_{II}$ of micro fracture is established to make the surrounding rock failure criterion more comprehensive and accurate. Further, the influence of the parameters related to the tension-shear mixed-mode fracture and compression-shear mixed-mode fracture on the propagation of rock crack is analyzed. Results show that ${\sigma}_3$ changes linearly with the change of ${\sigma}_1$. And the change rate is related to ${\beta}$, angle between the cracks and ${\sigma}_1$. The proposed simple analytical approach is economical and efficient, and suitable for the analysis of local nearly horizontal stratum in super-large section and deep buried tunnel.