Earticle

본 연구에서는 우뭇가사리 나노셀룰로스, 새싹삼 추출물, 담팔수 추출물이 포함된 복합소재의 제조 및 항균, 항염, 창상치유 효과를 연구하여 드레싱제의 원료로 활용하고자 한다. 이를 위해 나노셀룰로스 제조 검증, HPLC 분석을 통한 compound K와 Pentagalloylglucose 함량분석, 복합추출물 배합비에 따른 항균 활성 평가, NO 생성량을 통한 항염효능, SD rat을 통한 창상치유 검증을 수행하였다. 실험결과 각각의 추출물에 항균, 항염효능을 가지는 Compound K (0.38 ± 0.02 mg/mL) , PGG (177.67 μg/mL)가 포함된 정도와 SS3DP7에서 표피포도상 구균과 황색포도상구균에 대한 항균 효능을 확인하였다. 복합소재는 55% 이상의 항염증 효과와 창상 유발 후 1~2 일 차에 대조군 대비 10% 이상 높은 창상회복율이 관찰되었다. 추후 위와 같은 친환경 소재의 효능을 활용한 습윤 드레싱 제품 개발을 진행하고자 한다.

In this study, we will study the antibacterial, anti-inflammatory, and wound healing effects of a composite material containing Gelidium amansii nanocellulose, ginseng extract, and Elaeocarpus sylvestris var. elliptcus extract and use it as a raw material for a dressing. To this end, we performed verification of nanocellulose manufacturing, analysis of compound K and pentagalloylglucose contents through HPLC analysis, evaluation of antibacterial activity according to the mixing ratio of the composite extract, anti-inflammatory efficacy through NO production, and wound healing verification using SD rats. As a result of the experiment, the degree of Compound K (0.38 ± 0.02 mg/mL) and PGG (177.67 μg/mL) containing antibacterial and anti-inflammatory efficacy in each extract was confirmed, and antibacterial efficacy against Staphylococcus epidermidis and Staphylococcus aureus was confirmed in SS3DP7. The composite material showed an anti-inflammatory effect of more than 55%, and a wound healing rate higher than 10% was observed compared to the control group 1-2 days after wound induction. In the future, we plan to develop a wet dressing product that utilizes the efficacy of eco-friendly materials as described above.

4차 산업혁명 시대에 국방 무기체계가 첨단화되는 것을 고려할 때, 국방연구개발 능력은 국가안보의 초석으로서 국방력의 핵심이 된다고 할 수 있다. 한국은 2017년부터 국방연구 개발과 국가연구개발을 통합해서 관리하고 있으며, 2022년 국방 R&D를 위해 국방비의 8.8% 수준인 4조 8,310억 원의 예산을 확정하였다. 이러한 국방 R&D의 중요성과 천문학 적인 투입 재원을 고려할 때, 한국의 국방 R&D 효율성이 타 국가와 비교해 어느 정도 수 준인지 살펴보고 향후 정책 수립 시 활용하는 것은 매우 의미 있는 연구라 할 수 있다. 본 연구의 목적은 자료포락분석(DEA: Data Envelope Analysis)을 이용하여 OECD 회원국의 국방 R&D에 대한 상대적인 효율성을 정량적으로 측정하고, 국가별 효율성 수준을 비교함으로써 한국의 국방 R&D 사업이 OECD 회원국 가운데 어느 정도 효율적으로 운영되고 있는가를 분석하는 것이다. 실증분석을 위해 OECD 회원국 중 19개 국가를 선정 하였으며, 투입변수로 정부연구개발예산 대비 국방연구개발예산 비율, 연구원 수 그리고 산 출변수는 무기 수출액(추세지표값)으로 설정하였다. 분석결과 한국은 효율성이 높은 미국, 스페인에 비해 약 35%의 효율성을 보여 독일, 영 국 등과 유사한 수준이었으며, 연구개발 장려정책 등을 고려하여 투입규모를 줄이기보다는 현 수준을 유지하면서 ‘무기수출’ 증대를 통한 효율성 향상이 바람직한 것으로 분석되었다. 이를 위한 정책적 제언으로 첫 번째로는 민군협력에 대한 전폭적인 지원과 제도 발전 등을 통해 가시적인 성과를 제고해 나감으로써 무기수출 증대를 도모할 필요가 있다. 두 번째로 는 최근 미국의 국방 분야에 대한 공급망 개선 의지를 기회로 삼아야 한다. 국제협력 강화 를 통해 미국에서 국내 방위산업체가 시장 경쟁력을 가지고 지속적인 부품공급업체로 성장 할 수 있는 기반을 정부 차원에서 구축해야겠다. 이러한 실증분석 결과는 국가 재원의 효율적 집행과 관련하여 대국민 신뢰도 증진에 기여 할 수 있을 뿐만 아니라, 장기적인 안목에서의 국방 R&D 로드맵을 작성하는데 기초자료로 활용될 수 있을 것으로 기대한다.

Given that the defense weapon system is advanced in the era of the 4th industrial revolution, the defense R&D capability can be considered as a core of national security. Since 2017, Korea has integrated and managed defense R&D and national R&D, and in 2022, a budget of 4.831 trillion won, or 8.8% of defense spending, was allocated for defense R&D. Considering the importance of defense R&D and astronomical input resources, it is a very meaningful study to examine how much Korea's defense R&D efficiency is compared to other countries and use it in future policymaking. The purpose of this study is to quantitatively measure the relative efficiency of defense R&D using Data Envelope Analysis (DEA), and to analyze how efficient Korea's defense R&D project is among OECD members by comparing the level of efficiency by country. For empirical analysis, 19 OECD member countries were selected, and we used the ratio of the defense R&D budget to the government R&D budget, the number of researchers as input variables, and the amount of arms exports (Trend-Indicator Value) as output variables. As a result of the analysis, Korea showed an efficiency of about 35% compared to the highly efficient USA and Spain, which was similar to that of Germany and the UK. It was analyzed that it would be desirable to improve efficiency through increasing “arms exports” while maintaining the current level rather than reducing the amount of input in consideration of the R&D promotion policy, etc. As a policy suggestion for this, first, it is necessary to promote the increase in arms exports by improving tangible results through full support for civil-military cooperation and institutional development. Second, the United States' recent commitment to improving its supply chain to the defense sector should be used as an opportunity. By strengthening international cooperation, the government should establish a foundation for domestic defense companies to grow into continuous parts suppliers with market competitiveness in the United States. These empirical results are expected to contribute not only to improving public confidence in the efficient execution of state funds, but also to be used as basic data for preparing a roadmap for defense R&D in the long run.

본 연구는 기술력이 우수한 업체를 선정하고 평가의 신뢰성을 보장할 수 있는 무기체계 연구개발사업의 제안서평가체계를 마련하기 위해서다. 이를 위해 제안서평가에 영향을 미 치는 요인들을 평가항목, 가중치, 평가방법 등으로 구분하여 현행 제안서 평가체계의 한계 점을 분석하였다. 본 연구의 평가모형 개선에 관한 주요 연구내용은 다음과 같다. 첫째, 현행 평가모형의 평가요소를 기술개발능력과 사업이행능력으로 구분하고, 제안서 평가에서 핵심요소를 추출하기 위해 중요도-성취도분석(IPA)을 실시하였다. 둘째, 최종 채택된 평가요소는 현행 평가항목과 Mapping 방식을 통해서 계층구조를 재 설계하였고, 계층분석기법(AHP)을 적용해 객관적인 가중치를 산출하였다. 끝으로, 개선된 평가모형에 대한 전문가 설문조사를 통해 현행 평가모형과 비교해 상대 적으로 우수한 유효성을 확보하였다. 본 연구를 통해 개선된 제안서 평가제도는 경쟁력 있는 방위산업을 육성하는데 기여할 것으로 기대한다.

The purpose of this study is to develop a technical competence evaluation system to meet the purpose of evaluation (technical capability evaluation) of weapons system R&D project and ultimately to improve the evaluation system of proposals that can guarantee the reliability of evaluation. Findings of this study to improve evaluation model are as follows. First, “Importance-Performance Analysis(IPA)” technique was applied in this study to extract key elements to be used as evaluation items in proposal evaluation. Second, after selecting evaluation factors, hierarchical structure was redesigned through mapping method with existing evaluation items. Also objective weight was calculated by applying Analytic Hierarchy Process(AHP). Lastly, expert survey was found proposed model is superior to current evaluation model in terms of effectiveness. The proposed evaluation model is looking forward to contribute selecting providers with outstanding technical capability and project performance capability in phase of proposal evaluation, securing fairness and reliability of evaluation system.

As customers' demands for diversified small-quantity products have been increased, there have been great efforts for a firm to respond to customers' demands flexibly and minimize the cost of inventory at the same time. To achieve that goal, in SCM perspective, many firms have tried to control the inventory efficiently. We present an mathematical model to determine the near optimal (s, S) policy of the supply chain, composed of multi suppliers, a warehouse and multi retailers. (s, S) policy is to order the quantity up to target inventory level when inventory level falls below the reorder point. But it is difficult to analyze inventory level because it is varied with stochastic demand of customers. To reflect stochastic demand of customers in our model, we do the analyses in the following order. First, the analysis of inventory in retailers is done at the mathematical model that we present. Then, the analysis of demand pattern in a warehouse is performed as the inventory of a warehouse is much effected by retailers' order. After that, the analysis of inventory in a warehouse is followed. Finally, the integrated mathematical model is presented. It is not easy to get the solution of the mathematical model, because it includes many stochastic factors. Thus, we get the solutions after the stochastic demand is approximated, then they are verified by the simulations.

It has been recognized as an important issue to design optimally a firm's logistics network for minimizing logistics cost and maximizing customer service. It is, however, not easy to get an optimal solution by analyzing trade-off of cost factors, dynamic and interdependent characteristics in the logistics network decision making. Although there has been some developments in a system which helps decision making for logistics analysis, it is true that there is no system for enterprise-wise's on-site support and methodical logistics decision. Specially, E-biz process along with information technology has been made dramatic advance in a various industries, there has been much need for practical education closely resembles on-site work. The software developed by this study materializes efficient algorithm suggested by recent studies in key topics of logistics such as location and allocation problem, traveling salesman problem, and vehicle routing problem and transportation and distribution problem. It also supports executing a variety of experimental design and analysis in a way of the most user friendly based on Java. In the near future, we expect that it can be extended to integrated supply chain solution by adding decision making in production in addition to a decision in logistics.

Purpose: This study was conducted to assess the antidepressant effects of capsaicin in chronic depressive rats and elucidate the mechanism underlying its effects. Methods: Male Wistar rats (280~320 g, 8 weeks of age) were subjected to depression induced by chronic unpredictable mild stresses. The rats were exposed to 8 kinds of stresses for 8 weeks. In the last 2 weeks, fluoxetine or capsaicin was injected subcutaneously. The dose of fluoxetine was 10 mg/kg (body weight), while the doses of capsaicin consisted of low (1 mg/kg), middle (5 mg/kg), and high(10 mg/kg). The forced swim test (FST) was conducted to evaluate the immobility time of rats. The immobility time indicates despair, one of symptoms of depression. The change of tryptophan hydroxylase (TPH) in the dorsal raphe was investigated using immunohistochemistry. In the hippocampus cornu ammonis (CA) 1 and 3, glucocorticoid receptor (GR) expression was measured. Results: The immobility time in the FST was significantly lower (p < .05) in the low-dose (M = 32.40 ± 13.41 seconds) and middle-dose (M = 28.48 ± 19.57 seconds) groups than in the non-treated depressive rats (M = 90.19 ± 45.34 seconds). The amount of TPH in the dorsal raphe was significantly higher (p < .05) in the middle-dose (M = 249.17 ± 35.02) and high-dose (M = 251.0 ± 56.85) groups than in the non-treated depressive rats (M = 159.78 ± 41.16). However, GR expression in the hippocampus CA1 and CA3 did not show significant differences between the non-treated depressive rats and the capsaicin-injected rats. Conclusion: This study suggests that capsaicin produces an antidepressant-like effect on chronic unpredictable mild stress-induced depression in rats via the serotonin biosynthesis pathway.

얼굴과 표정 인식이 서로 완전히 병렬적이고 독립적인 과정인가를 확인하기 위해 얼굴 인식 및 표정 인식 과정에서 점화 효과를 측정하였다. 표정 인식 시간 측정 결과, 점화 자극이 목표 자극과 다른 사람의 얼굴이면서 동일한 표정인 경우에는 오히려 표정 인식 시간을 지연시키는 것으로 나타났다. 누구의 얼굴인지를 파악하는 얼굴 인식 과제에서는, 판단 이전에 제시된 얼굴의 표정은 얼굴 인식 시간에 유의한 영향을 미쳤으며 동일한 표정일 경우 얼굴 인식 시간을 단축시켰다. 표정 및 얼굴이 각기 다른 정보의 처리 시간에 미치는 이같은 영향은 두 정보가 서로 완전히 독립적으로 처리되지 않을 수 있음을 시사한다.

We measured the priming effects in face and facial expression recognition to examine if they are processed in separate channels. In facial expression recognition, the response times were found to be delayed when different faces with the same facial expressions were presented as the prime and the target. On the other hand, in face recognition, the latencies were affected by the expressions of the primes. Particularly, identical expressions in the paired faces shortened response times in identifying them. These results imply that face and facial expression are not processed in a totally parallel and independent way.

원자력발전소내 습식저장중인 사용후핵연료의 건식저장을 위해서는 캐니스터 내부에 사용후핵연료를 옮겨 담은 이후, 건 식저장 캐니스터 내장품이나 사용후핵연료 다발의 부식방지 및 피복관의 열화방지를 위해 모든 수분은 제거해야 한다. 캐 니스터 내부의 수분을 제거하는데 사용할 수 있는 기체강제순환 건조시스템 개발을 위한 연구개발이 진행중이다. 본 연구 에서는 기체강제순환 건조시스템 설계, 제작을 위한 예비설계를 수행하였다. 예비설계에는 캐니스터 내부 잔존수분 제거를 위한 건조사례조사, 건조관련 규격이나 표준, 건조합격기준, 건조장치구성, 현장요구분석, 습식저장중인 사용후핵연료 특성 을 포함하였다. 예비설계를 통하여 기체강제순환 건조시스템의 설계 개념도와 P&ID를 도출하였고, 이를 활용하여 건조시 스템 제작을 위한 상세설계를 수행할 것이다.

For dry storage of the spent nuclear fuel (SNF) stored in the storage pool of a nuclear power plant, essentially all moisture must be removed to prevent corrosion of the assembly and canister internals and/or degradation of fuel cladding integrity after SNF canister loading operation. R&D work is now in progress on a forced gas drying system that can be used to remove residual water in canisters. In this work, preliminary design is performed to manufacture the forced gas drying system. This process includes a case study of dry methods for canister moisture removal, relative codes and standards, confirmation of adequate dryness, needs analysis at plant sites, and characteristics of SNF stored in pools. Through this preliminary design work, we obtained a conceptual flow diagram and preliminary P&ID of the forced gas drying system. The results of this study can be used to determine details of the design to manufacture the forced gas drying system.

This study develops and evaluates a deep learning model for predicting oxide and nitride layers based on plasma process data. We introduce a novel deep learning-based Varying Coefficient Regressor (VCR) by adapting the VCR, which previously relied on an existing unique function. This model is employed to forecast the oxide and nitride layers within the plasma. Through comparative experiments, the proposed VCR-based model exhibits superior performance compared to Long Short-Term Memory, Random Forest, and other methods, showcasing its excellence in predicting time series data. This study indicates the potential for advancing prediction models through deep learning in the domain of plasma processing and highlights its application prospects in industrial settings.

정보통신기술 발전과 함께 4차 산업혁명 시대에 돌입하면서 신성장 산업으로 무인항공기 산업이 주목받기 시작했다. 소형 드론에서부터 대형 무인항공기까지 규모와 비행 공역의 범위도 다양해지면서 선진국(미국, 유럽)은 유인항공기와 무인항공기의 통합 운용에 대한 계획을 수립하고 있다. 또한, ICAO에서는 무인항공기의 국제기준 및 권고사항 수립을 하기 위해 관련 부속서 개정 작업을 수행하고 있다. 우리나라도 앞으로 도래할 유인항공기와 무인항공기의 통합 운영에 대비가 필요하여 이를 위해 무인항공기 안전운항에 대한 국내 제도 현황을 검토하고 정비해야 한다. 본 연구는 ICAO에서 논의하고 있는 원격조종항공기시스템(Remotely Piloted Aircraft System; RPAS) 관련 부속서의 개정사항들에 대해 분석하고 기존의 항공안전법과 비교하여 무인항공기 안전운항을 위한 항공안전법의 개정방향을 제시하였다.

With the development of information and communication technology, the unmanned aerial vehicle industry began to attract attention as a new growth industry as it entered the fourth industrial revolution. As the size of the unmanned aerial vehicles and the scope of airspace vary from small drones to large unmanned aerial vehicles, the developed countries such as USA and Europe are developing plans for the integrated operation of manned and unmanned aerial vehicles. ICAO is also working on amendments to the relevant ICAO annexes to establish international standards and recommendations for unmanned aerial vehicles. Korea also needs to prepare for the integrated operation of manned and unmanned aerial vehicles that will come in the future, and for this purpose, it is necessary to review and revise the national regulation systems for the safe operation of unmanned aerial vehicles. This study analyzes the amendments of related annexes discussed on the Remotely Piloted Aircraft System (RPAS) pannel, and suggests the direction of revision of the Aviation Safety Act for the safe operation of unmanned aerial vehicles in comparison with the existing Aviation Safety Act.

연구목적 본 연구는 한국 기혼 여성에서 만성적인 친밀한 관계에서의 폭력이 자살사고에 미치는 영향에 대해 조사하였다. 방 법 2014년부터 2018년까지의 한국복지패널의 자료를 사용하였으며 매년 조사된 설문을 이용하여 언어폭력 및 신체폭력이 우울증상 및 자살사고에 미치는 영향을 분석하였다. 나이, 교육수준, 경제수준, 음주, 종교, 만성질환, 가족관계 만족도, 사회관계 만족도 등을 공변량으로 하였다. 결 과 5년 간의 언어폭력 노출지수는 우울을 1.180배, 자살사고를 1.276배 높였으며 이는 우울증상의 영향을 보정해도 유의하였다. 반면, 5년 간의 신체폭력 노출지수는 우울을 1.486배, 자살사고를 1.362배 높였으며 우울증상의 영향을 배제하였을 때는 자살사고에 유의미한 영향을 주지 않았다. 결 론 이전에는 자살 사고가 없었던 여성에게 IPV가 장기적으로 지속되었을 때 우울증상의 유무와 상관없이 자살 사고를 높일 수 있다는 것을 밝혀낸 것에 의의가 있다. 위와 같은 결과를 고려하면 IPV를 경험한 여성에 대한 정신과적 개입이 자살률을 줄이는 데 도움이 될 것이다.

Objectives : This study looked at the effects of chronic IPV on suicide ideation among married women in the country. Methods : This study used data from the five-year-old Korea Welfare Panel and analyzed using questions about verbal and physical violence, depression and suicide ideation that were investigated every year. Age, education, and economic levels, drinking, religion, chronic disease, satisfaction with family relationship, satisfaction with social relationship, were included as variables. Results : The five-year cumulative score of verbal violence had a statistically significant effect on the depressive symptom, and the relative risk was 1.180. The relative risk of five-year-old cumulative score of verbal violence in suicidal ideation was 1.276, and it was also significant even if they exclude the effects of depressive symptom. On the other hand, the five-year cumulative score of physical violence was found to have no significant impact on suicide ideation if they excluded the effects of depressive symptom. Conclusions : Unlike previous studies, this study found that chronic verbal IPVs increase suicide ideation, even though they do not contain effects of depression. Such findings suggest that intervention in IPV in married women may help reduce the nation's suicide rate.

연구목적 자살행동의 계절성은 잘 알려져 있는 현상이지만, 자해행동의 계절성은 알려진 바가 적다. 본 연구는 자해행동 중 하나인 손목자해행동이 계절성을 나타내는지를 확인하고, 기후인자와의 관련성을 파악하고자 했다. 방 법 자해행동의 계절성을 확인하기 위하여 2014. 12~2019. 5까지 일 병원 응급실에 손목자해행동으로 내원한 226명의 대상자의 월별 평균 내원 숫자가 월별로 차이를 나타내는지를 보았다. 손목자해행동과 기후인자와의 관련성을 확인하기 위하여 월 단위 시간변수와 기상청 데이터를 통해 획득한 월별 기후변수(기온, 일조량, 1개월 전 대기압)를 설명변수로 하고, 월 별로 손목자해행동으로 응급실에 내원한 횟수를 결과변수로 하여 일반화 가법모형을 이용한 다중 포아송 회귀분석을 실시하였다. 결 과 손목자해행동으로 응급실에 내원한 대상자의 월 평균 숫자는 남자에서 유의한 월별 차이가 있었고, 9월에 가장 많았다(남자 : p=0.048, 여자 : p=0.21, 전체 : p=0.28). 다중 회귀분석 결과 손목자해로 응급실에 내원한 월 평균 환자의 숫자는 남자에서는 1달전 대기압과 기온의 교호작용과 관련이 있었고(p=0.010), 여자에서는 일조량과 양의 상관관계[p=0.044, β=4.70×10-3, 95% CI=(1.19×10-4, 9.27×10-3)]를 보였다. 결 론 손목자해행동은 남성에서 두드러진 계절성을 보이며, 이는 기후변수의 변화와 관련성이 있다.

Objectives : Although the seasonality of suicide is a well-known phenomenon, little is reported about the seasonality of non-suicidal self-injury. The purpose of this study was to identify the seasonality of wristcutting behavior and to examine its relationship with meteorological factors. Methods : To identify the presence of seasonality, we investigated whether there was a difference in the average number of visits per month to an emergency room (ER) of an urban hospital for 226 patients with wrist-cutting behavior enrolled between December 2014 and May 2019. To ascertain significant meteorological factors, we used the multiple Poisson regression using generalized additive model with time, monthly temperature, monthly sunshine hour, and atmospheric pressure in the prior month as explanatory variables. Results : In males, the average number of monthly visits to the ER for wrist cutting behavior differed by month and was the highest in September (male : p=0.048, female : p=0.21, total : p=0.28). As a result of multiple regression analysis, the average number of patients admitted to the ER for wrist cutting behavior was related to the interaction between atmospheric pressure in the prior month and temperature in males (p=0.010), and showed a positive correlation with sunlight in females [p=0.044, β=4.70×10-3, 95% CI=(1.19×10-4, 9.27×10-3)]. Conclusions : Wrist cutting behavior shows seasonality in male, which is associated with changes in meteorological variables.

In this study, we tried to derive the most severe scenario and its critical speed by 1-D collision simulation with a variable formation vehicle in order to prepare for the change of demand in Seoul Metropolitan Subway Line 3, which is operated by fixed arrangement. After establishing various collision scenario conditions, the friction coefficient between the wheel and the rail was evaluated as 0.3, which is considered to be severe. As a result of analysis according to all scenarios, the most severe scenario conditions were confirmed by comparing rubber shock absorber performance and vehicle collision deceleration. In addition, a typical wheel-rail friction coefficient was derived through accident cases, and the analysis was performed again and compared. Finally, the criterion of the critical speed in the condition of the friction coefficient of the normal wheel - rail condition was confirmed.

강관말뚝 두부정리 작업은 안전성, 품질의 균일성, 작업 생산성 측면에서 개선이 필요하며, 이를 개선하기 위한 자동화 및 기계화 등 대안마련이 시급한 실정이다. 본 연구의 목적은 상기 문제점을 개선할 수 있는 굴삭기 기반 강관말뚝 두부정리 및 절단 부위 핸들링 로봇의 풀스케일 프로토타입을 개발하는 것이다. 이를 위해 본 연구에서는 1)선행기술 분석 및 현장 전문가 설문조사, 2)AHP 분석을 활용한 핵심 요소기술 선정, 3)상세설계 도출, 4)구조적 안정성 분석, 5)풀스케일 프로토타입 개발을 수행하였다. 핵심 요소기술 선정 결과, 레이저 레벨기 및 수광기(94.46점), 강관말뚝 절단 기능에서는 플라즈마 절단(96.72점), 강관말뚝 인양 및 운반 기능에서는 회전형 그래플(93.45점)이 선정되었으며, 구조적 안정성 분석 결과, 구조적으로 가장 취약할 것으로 판단되는 3개 부재(그립부, 실린더 피벗 브라켓, 그립부 베이스)에서 최소 2배 이상의 구조적 안정성을 확보할 수 있는 것으로 분석되었다. 최종적으로 개발된 풀스케일 프로토타입은 센싱부 정확도 3.39mm, 절단부 절단 속도 1분 59초로 강관말뚝 두부정리 작업의 자동화를 위한 충분한 성능을 확보한 것으로 분석되었다. 본 연구를 통해 개발된 굴삭기 기반 강관말뚝 두부정리 및 절단 부위 핸들링 로봇은 현업에서의 요구가 충분히 반영되고 기술적 타당성이 확보되었으므로 그 실용화 가능성이 높을 것으로 기대된다.

The primary objective of this study is to develop an all-in-one based steel pipe pile cutting robot prototype that improves the conventional steel pipe pile head cutting work in safety, quality, and productivity. For this, the following research works are conducted sequentially; 1)literature review and expert survey, 2)selection of core technology using AHP analysis, 3)deduction of detail design, 4)verification of structural stability, 5)development of full-scale prototype. As a result leveling laser and laser detector(94.46), plasma cutter(96.72), rotary grapple(98.45) are selected as a core technologies. As an outcome, it is analyzed that gripper, cylinder pivot bracket and gripper base are structurally stable. Their maximum stresses are shown as 43.0%, 19.4%, 5.3% compared to their yield strength respectively. The development of full-scale prototype in this study will be utilized for the development of the all-in-one attachment based steel pipe pile cutting robot commercialization model.

Objectives Although impulsivity has long been thought as an important factor influencing suicidal behaviors, it is unknown whether impulsivity increases the risk of dying from suicidal behaviors and what specific component among constructs of impulsivity contributes to the risk of dying among suicide attempters. Methods To elucidate the association between impulsivity and medical lethality of suicide attempt among suicide attempters, we consecutively recruited 46 suicide attempters who visited an emergency room of a general hospital located in a metropolitan area, Seoul, Republic of Korea, due to suicide attempts and consented to participate in this study. Then we assessed medical lethality with the Beck Lethality Scale (LS) and impulsivity with the Korean version of the Barratt Impulsiveness Scale-11-Revised (BIS). Demographic variables were obtained from medical records and structured social work reports for suicide attempters. Results Although total scores of the BIS did not correlate with LS scores, only the scores of self-control, that is one of the Barrett's six theoretical constructs of impulsivity in which the higher score indicates less self-control and more impulsivity, had a significant positive correlation with scores of LS (p = 0.003). The association remained significant after adjusting for variables known to affect suicide lethality such as job status, recent alcohol consumption, diagnosis of depressive disorders, and having a plan for suicide (${\beta}=0.429$, p = 0.009). Conclusions Not impulsivity in general, but poor self-control, in particular, predicts lethal suicidal behaviors among suicide attempters. The degree of self-control should be evaluated when assessing patients with elevated suicide risk, and proper measures should be installed to prevent possible future lethal suicide attempts.

This paper is to introduce the main modeling assumptions and data structures associated with right-censored data to describe the successful methodological ideas for analyzing such a field-failure-data when components operating in different environments. The Kaplan - Meier method is the most popular method used for survival analysis. Together with the log-rank test, it may provide us with an opportunity to estimate survival probabilities and to compare survival between groups. An important advantage of the Kaplan - Meier curve is that the method can take into account some types of censored data, particularly right-censoring. The above non-parametric method was used to verify the equality of parts life used in different environments. After that, we performed the life distribution analysis using the parametric method. We simulated data from three distributions: exponential, normal, and Weibull. This allowed us to compare the results of the estimates to the known true values and to quantify the reliability indices. Here we used the Akaike information criterion to find a suitable life time distribution. If the Akaike information criterion is the smallest, the best model of failure data is presented. In this paper, no-nparametrics and parametrics methods are analyzed using R program which is a popular statistical program.