• 식물병연구
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• 제18권1호
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• pp.17-23
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• 2012

Xenorhabdus nematophila K1의 대사물질 인돌의 고추역병과 탄저병에 대한 농용살균제로의 개발 가능성을 검토하였다. 인돌은 역병균과 탄저병균의 균사신장을 강하게 억제하였다. 이러한 항균력은 자연상태의 태양 조사 조건 아래에서 60일 이상 유지되었으며, 토양수에서도 상실되지 않았다. 고추를 밭에 정식하기 전에 인돌 현탁액을 토양에 살포하고 10일 간격으로 고추의 지상부에 살포하여, 약 30%의 주요 병해 발생 감소를 가져왔다. 이러한 결과는 indole을 고추 역병과 탄저병 방제를 위해 사용할 수 있음을 의미한다.

• 한국진공학회지
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• 제22권4호
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• pp.175-180
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• 2013

본 연구에서는 반도체 소자 생산 공정 중 발생하는 오염입자에 의해 실시간 오염입자 측정장치인 In-Situ Particle Monitor(ISPM)의 광학창의 오염을 방지하기 위한 모듈 개발에 관한 연구이다. 개발한 광학창 오염방지 모듈은 실시간으로 측정하는 ISPM 내 광학창 표면에 오염입자가 흡착되는 것을 방지하기 위한 장치로 적합한 초음파 모듈 개발이 성공적 연구의 핵심내용이다. 또한 그 효과를 극대화하기 위한 구조적인 최적화도 필요하지만 초음파 힘의 표면 전달효율 향상 기술도 개발이 필요한 핵심 기술이다. 개발된 광학창 오염방지 모듈이 장착된 ISPM은 양산용 증착공정 장비(BPSG 증착장비) 배기구에 설치되었으며, 공정조건 별 오염방지 모듈의 성능과 더불어 ISPM 측정 효율도 함께 검증하였다.

• 한국지능시스템학회논문지
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• 제20권4호
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• pp.509-515
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• 2010

부산과 경남의 경우 해안가뿐 만 아니라 습지 지역과 지역을 통과하는 낙동강의 넓은 남해안 벨트 등 다양한 형태의 환경으로 둘러싸여있다. 이러한 다양한 형태의 부정형 지역에서 활동할 수 있는 로봇의 이동 플랫폼이 요구되고 있다. 하지만 이러한 지형에 바퀴가 달린 감시로봇을 사용한다면 모래나 습지표면에 바퀴가 빠져 움직일 수 없다. 또한, 관절 로봇은 속도가 느리고 몸체가 움직일 때마다 기울어져 넘어질 수 있다. 따라서 본 연구에서는 모래 위, 습지에서 효과적으로 보행할 수 있는 메커니즘을 개발하는 것이다. 개발한 생물체 로봇에 카메라, 적외선 센서 등을 장착하고, 이 센서들을 이용하여 소프트 컴퓨팅 알고리즘을 이용하여 주위 환경에 반응하도록 한다. 또한 블루투스 통신 모듈을 장착하여 외부와 통신하며 외부의 명령에 순응하는 행동을 할 수 있게 한다. 본 연구의 최종 목표는 습지, 모래, 물 위에서 가장 적합하게 작동할 수 있는 생물체를 로봇으로 구현하고, 게 로봇에 부착된 카메라 정보를 통해 필요부분을 감시할 수 있으며, 컴퓨터에 전송된 화면을 보고 사용자가 로봇을 제어 할 수 있는 지능형 로봇을 제작하는 것이다.

• Geomechanics and Engineering
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• 제13권5호
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• pp.715-742
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• 2017

Earth berms are often left in place to support retaining walls or piles in order to eliminate horizontal struts in excavations of soft soil areas. However, if the excavation depth is relatively large, an earth berm-supported retaining system may not be applicable and could be replaced by a multi-bench retaining system. However, studies on multi-bench retaining systems are limited. The goal of this investigation is to study the deformation characteristics, internal forces and interaction mechanisms of the retaining structures in a multi-bench retaining system and the failure modes of this retaining system. Therefore, a series of model tests of a two-bench retaining system was designed and conducted, and corresponding finite difference simulations were developed to back-analyze the model tests and for further analysis. The tests and numerical results show that the distance between the two rows of retaining piles (bench width) and their embedded lengths can significantly influence the relative movement between the piles; this relative movement determines the horizontal stress distribution in the soil between the two rows of piles (i.e., the bench zone) and thus determines the bending moments in the retaining piles. As the bench width increases, the deformations and bending moments in the retaining piles decrease, while the excavation stability increases. If the second retaining piles are longer than a certain length, they will experience a larger bending moment than the first retaining piles and become the primary retaining structure. In addition, for varying bench widths, the slip surface formation differs, and the failure modes of two-bench retained excavations can be divided into three types: integrated failure, interactive failure and disconnected failure.

• 지질공학
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• 제31권3호
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• pp.269-281
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• 2021

Land creeping is the imperceptibly slow, steady, downward movement o f slope-forming soil or rock. Because creep-related failures occur frequently on a large scale without notice, they can be hazardous to both property and human life. Korea Forest Service has operated the prevention and response system from land creeping which has been on the rise since 2018. We categorized and proposed three survey steps (e.g., preliminary, regional, detailed) for investigation of creeping susceptibility site with a focus on geophysical mapping of a selected test site, Yongheung-dong, Pohang, Korea. The combination of geophysical (dipole-dipole electrical resistivity tomography and reciprocal seismic refraction technique, well-logging), geotechnical studies (standard penetrating test, laboratory tests), field mapping (tension cracks, uplift, fault), and comprehensive interpretation of their results provided the reliable information of the subsurface structures including the failure surface. To further investigate the subsurface structure including the sliding zone, we performed high-resolution geophysical mapping in addition to the regional survey. High-resolution seismic velocity structures are employed for stability analysis because they provided more simplified layers of weathering rock, soft rock, and hard rock. Curved slip plane of the land creeping is effectively delineated with a shape of downslope sliding and upward pushing at the apex of high resistive bedrock in high-resolution electrical resistivity model with clay-mineral contents taken into account. Proposed survey steps and comprehensive interpretation schemes of the results from geological, geophysical, and geotechnical data should be effective for data sets collected in a similar environment to land-creeping susceptibility area.

• Physical Therapy Rehabilitation Science
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• 제10권4호
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• pp.503-511
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• 2021

Objective: This study compared pain, muscle power (MP), muscle thickness (MT), and normalized position of the scapula (POS) between general physical therapy and general physical therapy with strengthening exercises of the lower trapezius in patients with rounded shoulder and chronic neck pain. Design: Randomized controlled trial. Methods: The participants were 30 patients of W hospital in Gangnamgu, Seoul, with rounded shoulders who were diagnosed with chronic neck pain. Rounded shoulder was defined as a distance between the surface and acromion of >1 inch in the supine position. The participants were assigned to an experimental group (n=15) and a control group (n=15). The experimental group completed four types of strengthening exercises program for 15 minutes, twice weekly, for a total of 5 weeks. Soft tissue mobilization (STM), cervical extension flexion rotation (CEFR), and physical modality were also performed in both groups. Results: The degree of pain was assessed using the numerical rating scale (NRS), MP was measured a handheld dynamometer, MT was measured by ultrasound, and POS was measured using a tapeline. Significant between-group differences were observed in VAS, MP, MP, and POS. Significant changes were observed in the experimental group for VAS, MP, MT, and POS. Conclusions: Based on the results of this study, it was indicated that lower trapezius strengthening exercises performed together with general physical therapy was significantly improved in pain, MP, MT, and POS in patients with rounded shoulder and chronic neck pain compared to when general physical therapy was performed alone.

• 한국환경농학회지
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• 제37권3호
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• pp.221-228
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• 2018

BACKGROUND: Spoilage fungi can reduce the shelf life of fresh fruits and cause economic losses by lowering quality. Especially, mulberry fruits have high sensitivity to fungal attack due to their high water content (> 70%) and soft texture. In addition, the surface of these fruits is prone to damage during harvesting and postharvest handling. However, any study on postharvest spoilage fungi in mulberry fruit has not been reported in Korea. This study aimed to examine the spoilage fungi occurring in mulberry fruits during storage after harvest. METHODS AND RESULTS: In this study, we isolated postharvest spoilage fungi from mulberry fruits stored in refrigerator (fresh fruits) and deep-freezer (frozen fruits) and identified them. In the phylogenetic analysis based on comparisons of the ITS rDNA sequences, the 18 spoilage fungi isolated from mulberry fruits and the 25 reference sequences were largely divided into seven groups that were subsequently verified by high bootstrap analysis of 73 to 100. Alternaria spp. including A. alternate and A. tenuissima, were the most frequently isolated fungi among the spoilage isolates: its occurrence was the highest among the 18 isolates (38.9%). CONCLUSION: The findings of this study will be helpful for increasing the shelf life of mulberry fruits through the application of appropriate control measures against infection by spoilage fungi during storage.

• 한국응용과학기술학회지
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• 제36권1호
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• pp.305-311
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• 2019

높은 함수율을 갖는 소프트렌즈를 제조하기 위하여 아크릴계 공중합체를 설계, 제조하였다. 공중합체용 모노머로 2-hydroxyethyl methacrylate(HEMA)를 사용하였고 가교제로는 ethylene glycol dimethacrylate(EGDMA), glycerol dimethacrylate(GD) 혹은 glycerol 1,3-diglycerolate diacrylate(GDD)를 이용하여 렌즈를 제조하였다. 함수율 측정결과, 고함수율 렌즈는 기존의 36%에서 46%로 높게 나타났으며 접촉각도 38.6 에서 34.4 로 낮아져 표면 친수성이 높게 나타남을 확인하였다. 인장강도는 가교제의 친수성이 증가함에 따라 0.1MPa 에서 0.08 그리고 0.05 로 감소하였고 전자현미경으로 렌즈의 단면을 확인한 결과 상분리 현상은 나타나지 않았다. 광중합은 Real-time infrared(RTIR)로 측정하였는데 초기 중합 속도가 가교제에 따라 0.6 에서 0.9 로 나타났다.

• Geomechanics and Engineering
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• 제24권4호
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• pp.307-321
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• 2021

In an earlier publication (Serrano et al. 2014), the theoretical basis for evaluating the shear strength in rock joints was presented and used to derive an equation that governs the relationship between tangential and normal stresses on the joint during slippage between the joint faces. In this paper, the theoretical equation is applied to two non-linear failure criteria by using non-associated flow laws, including the modified Hoek and Brown and modified Mohr-Coulomb equations. The theoretical model considers the geometric dilatancy, the instantaneous friction angle, and a parameter that considers joint surface roughness as dependent variables. This model uses a similar equation structure to the empirical law that was proposed by Barton in 1973. However, a good correlation with the empirical values and, therefore, Barton's equation is necessary to incorporate a non-associated flow law that governs breakage processes in rock masses and becomes more significant in highly fractured media, which can be induced in a rock joint. A linear law of dilatancy is used to assess the importance of the non-associated flow to obtain very close values for different roughness states, so the best results are obtained for null material dilatancy, which considers significant changes that correspond to soft rock masses or altered zones of weakness.

• 대한통합의학회지
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• 제9권2호
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• pp.13-21
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• 2021

Purpose : Instrument-assisted soft tissue mobilization (IASTM) has been widely used to improve pain and range of motion. However, research on IASTM using vibration stimulation is lacking. Therefore, this study investigates how IASTM using vibration stimulation affects chronic pain on muscle activity and flexibility of the shoulders. Methods : A total of 20 patients with chronic shoulder pain were divided into the experimental group and the control group. The experimental group (n=10) used vibration stimulus for IASTM, while the control group (n=10) used general IASTM. For six weeks, this training lasted for 30 min a day, twice a week. Muscle activity was evaluated using the surface electromyograph. The back and reach test was used to assess flexibility, the visual analogue scale to measure pain, and the paired t-test to compare the groups before and after the experiment. An independent ANCOVA was conducted to assess differences in the degree of transition between the two groups before and after the experiment. Results : Significant differences in muscle activity, flexibility, and pain in both groups before and after the experiment (p<0.05) were observed, as well as in the muscle activity of the pectoralis major and associated pain (p<0.05). however, muscle activity and flexibility of the upper trapezius and infraspinatus were not significantly different between groups (p>0.05). Conclusion : This study confirms the importance of IASTM using vibration. Design and manufacture of IASTM using vibration based on our results would be useful in the management of shoulder pain, Further clinical evidence are needed.