• Geomechanics and Engineering
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• 제15권4호
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• pp.957-964
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• 2018

In this study, a method of electrochemical consolidation is applied. This method utilizes electro-osmosis, which is an effective ground improvement technique for soft clays, and soil treatment using lime, which is the oldest traditional soil stabilizer. The mechanism of lime treatment for soil involves cation exchange, which leads to the flocculation and agglomeration. Five representative laboratory tests-an electro-osmotic test and four electrochemical tests with various proportions of lime-were performed on dredged marine clay. The objectives of this study are to investigate the effect of electrochemical treatment and to determine the optimum dose for optimal consolidation performance of dredged marine clay. The results show that a better consolidation effect was achieved in terms of current, temperature, and vane shear strength by using electrochemical treatment. The best results were observed for the electrochemical test using 4% lime content.

• 대한한방소아과학회지
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• 제18권1호
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• pp.207-220
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• 2004

Objective: This study was conducted to find out the effect of saruktanggamibang(SRT) on memory and learning of rats. Methods: The mon·is water maze was used. It was performed Acquisition test, Retention test of water maze. After Behavioral test, it was investigated AChE cell numbers of CAI and CA3 on hippocampus. Results: of water maze revealed that acqusitive abilities of SAP+SRT group significantly improved on 3, 4, 5th day compared with SAP+Saline group. Retention test of water maze didn't reveal that retentive abilities of SAP+SRT group significantly improved comparing with another group. ChAT cell numbers of medial septum of SAP+SRT group significantly increased compared with SAP+Saline group. AChE cell numbers of CAl and CA3 on hippocampus of Sham+SRT group significantly increased compared with Sham group. And AChE cell numbers of CAl and CA3 on hippocampus of SAP+SRT group significantly increased compared with SAP+Saline group. Conclusion: Saruktanggamibang(SRT) has an effect on memory and learning of rats.

• Structural Engineering and Mechanics
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• 제41권1호
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• pp.95-112
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• 2012

In order to analyze the experimental hysteretic behavior of the in-plane loaded reinforced grouted multi-ribbed aerated concrete blocks masonry walls (RGMACBMW), we have carried out the pseudo static testing on the six specimens of RGMACBMW. Based on the test results and shear failure characteristics, the shear force hysteretic curves and displacement envelope curves of the models were obtained and discussed. On the basis of the hysteretic curves a general skeleton curve of the shear force and displacement was formed. The restoring model was adopted to analyze the seismic behavior and earthquake response of RGMACBMW. The deformation capacity of the specimens was discussed, and the formulas for calculating the lateral stiffness of the walls at different loading stages were proposed as well. The average lateral displacement ductility factor of RGMACBMW calculated based on the test results was 3.16. This value illustrates that if the walls are appropriately designed, it can fully meet the seismic requirement of the structures. The quadri-linear restoring models of the walls degradation by the test results accurately reflect the hysteretic behaviors and skeleton curves of the masonry walls. The restoring model can be applied to the RGMACBMW structure in earthquake response analysis.

• Computers and Concrete
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• 제26권2호
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• pp.115-125
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• 2020

To reduce the damage of concrete in fire, a new type of lightweight cinder aggregate concrete was developed due to the excellent fire resistance of cinder. To further enhance its fire resistance, Polypropylene (PP) Fibers which can enhance the fire resistance of concrete were also used in this type of concrete. However, the bond behavior of this new type of concrete after fire exposure is still unknown. To investigate its bond behavior, 185 specimens were heated up to 22, 200, 400, 600 or 800℃ for 2 h duration respectively, which is followed by subsequent compressive and tensile tests at room temperature. The concrete-rebar bond strength of C30 PP fiber-reinforced cinder concrete was subsequently investigated through pull-out tests after fire exposure. The microstructures of the PP fiber-reinforced cinder concrete and the status of the PP fibre at different temperature were inspected using an advanced scanning electron microscopy, aiming to understand the mechanism of the bonding deterioration under high temperature. The effects of rebar diameter and bond length on the bond strength of PP fiber-reinforced cinder concrete were investigated based on the test results. The bond-slip relation of PP fiber-reinforced cinder concrete after exposure at different temperature was derived based on the test results.

• 정보교육학회논문지
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• 제5권1호
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• pp.69-78
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• 2001

최근에, 컴퓨터를 이용한 학습은 CAI 환경에서 WBI 학습 환경으로 옮아가고 있다. WBI 학습에 필요한 대부분의 웹 문서는 검색 엔진을 이용하여 얻는다. 교수자는 검색한 웹 문서의 사용가능성을 평가한 후 학습 자료로 사용한다. 그러나 이런 교수-학습 과정은 다음과 같은 문제점이 있다. 첫째, 교수자에 의해 선정된 웹 문서를 반복해서 검색한다. 둘째, 웹 문서를 학습자에게 제시하기 위한 별도의 교수 설계 과정이 필요하다. 셋째, 학습자의 평가 결과와 웹 문서 사이의 관련성 분석이 매우 어렵다. 본 연구에서는 WBI 학습에 필요한 웹 문서를 검색하고 학습자에게 학습 과정을 안내하는 WAILS(Web Agent Instruction Learning System)를 제안한다. WAILS는 웹 에이전트를 이용하여 WBI 학습에 필요한 웹 문서를 수집한다. 교수자는 수집한 웹 문서를 평가하고 교수-학습 생성기를 통해 학습자에게 제시한다. 교수자는 WAILS를 이용하여 웹 문서의 검색과 교수-학습 설계를 동시에 하게 된다. 이는 WBI 학습을 더욱 촉진시키게 된다.

• Asian Pacific Journal of Cancer Prevention
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• 제15권17호
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• pp.7223-7228
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• 2014

The MYH11 gene may be related to cell migration and adhesion, intracellular transport, and signal transduction. However, its relationship with prognosis is still uncertain. The aim of this study was to investigate correlations between MYH11 gene expression and prognosis in 58 patients with stage II and III colorectal cancer. Quantitative real-time polymerase chain reaction was performed in fresh CRC tissues to examine mRNA expression, and immunohistochemistry was performed with paraffin-embedded specimens for protein expression. On univariate analysis, MYH11 expression at both mRNA and protein levels, perineural invasion and lymphovascular invasion were related to disease-free survival (p<0.05; log-rank test). Cancers with lower MYH11 expression were more likely to have a poor prognosis. Otherwise, MYH11 expression was unrelated to patient clinicopathological features. On multivariate analysis, low MYH11 expression proved to be an independent adverse prognosticator (p<0.05). These findings show that MYH11 can contribute to predicting prognosis in stage II and III colorectal cancers.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집A
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• pp.250-255
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• 2000

Damage induced by low velocity impact loading in aircraft composite laminates is the form of failure which is occurred frequently in aircraft. Low velocity impact can be caused either by maintenance accidents with tool drops or by in-flight impacts with debris. As the consequences of impact loading in composite laminates, matrix cracking, delamination and eventually fiber breakage for higher impact energies can be occurred. Even when no visible impact damage is observed, damage can exist inside of composite laminates and the carrying load of the composite laminates is considerably reduced. The reduction of strength and stiffness by impact loading occurs in compressive loading due to laminate buckling in the delaminated areas. The objective of this study is to determine inside damage of composite laminates by impact loading and to determine residual compressive strength and the damage growth mechanisms of impacted composite laminates. For this purpose a series of impact and compression after impact tests are carried out on composite laminates made of carbon fiber reinforced epoxy resin matrix with lay up pattern of $[({\pm}45)(0/90)_2]s$ and $[({\pm}45)(0)_3(90)(0)_3({\pm}45)]$. UT-C scan is used to determine impact damage characteristics and CAI(Compression After Impact) tests are carried out to evaluate quantitatively reduction of compressive strength by impact loading.

• Journal of the Korean Data and Information Science Society
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• 제25권5호
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• pp.971-986
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• 2014

동시에 여러 개의 가설검정 수행시 귀무가설이 참일 경우 귀무가설을 기각할 확률이 커지는 문제가 발생한다. 이러한 다중검정 문제 해결을 위해 여러 연구에서는 가설검정시 필요한 집단별 오류율(FWER; family-wise error rate), 위발견율 (FDR; false discovery rate) 또는 위비발견율 (FNR; false nondiscovery rate) 과 통계량을 고려하여 검정력을 높이고자 하였다. 본 연구에서는 T 통계량, 수정된 T 통계량, 그리고 LPE (local pooled error) 통계량 기반 P값을 이용한 Bonferroni (1960) 방법, Holm (1979) 방법, Benjamini와 Hochberg (1995) 방법과 Benjamini와 Yekutieli (2001) 방법 그리고 Z 통계량 기반 Sun과 Cai (2007) 방법을 고찰하고 모의실험을 통해 다중검정 능력을 비교하였다. 또한 실제 데이터로 애기장대 유전자 발현 데이터에 대해 여러 가지 다중검정법을 통해 유의한 유전자들을 선별하였다.

• The Journal of Korean Physical Therapy
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• 제34권3호
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• pp.91-97
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• 2022

Purpose: This study investigated the short-term effectiveness of extracorporeal shock wave therapy (ESWT) on pain, the ankle instability, the ankle function, dorsiflexion range of motion (ROM), and dynamic balance in patients with chronic ankle instability (CAI). Methods: Eighteen participants were divided into an experimental (n=9) and control group (n=9). The ESWT in the experimental group was applied to the lateral collateral ligament in combination with the tibialis anterior whereas the ESWT was applied to the lateral collateral ligament of the ankle alone in the control group. Pain, the ankle instability, the ankle function, dorsiflexion ROM, and dynamic balance were measured using the Visual analog scale, Cumberland ankle instability tool, American Orthopedic Foot and Ankle Society ankle-hindfoot score, weight-bearing lunge, and Y-balance test, before and after ESWT intervention. Results: Significant interactions (group × time) and time effects were observed in the dorsiflexion ROM and dynamic balance. Bonferroni's post-hoc analysis showed that the experimental group revealed a more significant change in dorsiflexion ROM and dynamic balance than the control group. There was a significant time effect in the pain, the ankle instability, and the ankle function, but no significant interaction (group × time) was observed. Conclusion: The ESWT could improve the pain, ankle instability, ankle function, dorsiflexion ROM, and dynamic balance in patients with CAI. Furthermore, the ESWT combined with lateral ankle ligaments and tibialis anterior more improves the dorsiflexion ROM and dynamic balance.

• 대한화학회지
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• 제51권1호
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• pp.56-64
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• 2007

이 연구에서는 변칙사례 및 대안가설에 의해 유발된 인지갈등과 불안, 주의집중, 노력이 개념변화에 미치는 영향을 조사하였다. 중학교 1학년 학생 470명을 대상으로 선개념 검사를 실시하여 203명의 오개념을 지닌 학생들을 선발하였다. 변칙사례를 제시한 후, 대안가설 제시 전후에 각각 변칙사례에 대한 반응 검사와 불안검사를 실시하였다. CAI 프로그램으로 밀도 개념학습을 실시하였으며, 사후 검사로 주의집중 검사, 노력 검사, 개념 검사를 실시하였다. 연구 결과, 변칙사례에 의해 유발된 인지갈등(사전 인지갈등)은 대안가설 제시 후 증가하였다. 사전 인지갈등은 변칙사례와 대안가설에 의해 유발된 인지갈등(사후 인지갈등)에만 직접적인 영향을 주었으며, 사후 인지갈등은 개념변화에 직접적으로 긍정적인 영향을 주었다. 변칙사례에 의해 유발된 불안(사전 불안)은 대안가설 제시 후 감소하였다. 사전 불안은 변칙사례와 대안가설에 의해 유발된 불안(사후 불안)에만 직접적인 영향을 주었으며, 사후 불안은 노력을 통해 개념변화에 부정적인 영향을 주었다. 주의집중은 개념변화에 직접적으로 또는 노력을 경유하여 긍정적인 영향을 주었다. 이런 결과는 개념변화 수업에서 변칙사례와 대안가설을 함께 제시하는 전략이 변칙사례만 제시하는 전략보다 인지갈등을 더욱 유발하거나 불안을 감소시켜 학생들이 개념학습 과정에 보다 능동적이고 적극적으로 참여하도록 유도함으로써 개념변화를 촉진할 가능성을 시사한다.