지금까지의 노인자살 연구들은 대부분이 노인자살에 관한 이론적 조망과 그에 따른 노인자살 요인들을 파악하는 데 집중되어 왔다. 그래서 노인자살의 예방대책에 관한 논의는 개괄적이고 제안적인 수준에 머 무르고 있다. 현재 우리나라는 자살사고를 효과적으로 예방하기 위한 자살예방사업 및 인프라가 극히 미비한 상태이 며 특히 노인자살의 특수성이 정책에 반영되지 못하고 있다. 우리사회에서 사회적 이슈가 되고 있는 노인 자살문제에 대해 효과적이고 실효성 있는 정책과 대안을 제시하기 위해서는 노인자살에 대한 정확한 특성 과 실태에 대한 분석이 필요하다. 이에 본 연구자는 통계청에서 제시하고 있는 마이크로데이터를 활용해 MDIS(MicroData Integrated Service)에서 2017년 10월 31일 공개된 통계 기초자료(Microdata)인 인구동향조사 「2016년 사망(원인) 통계」마이크로데이터를 수집하여 우리나라 자살에 대한 특성 및 실 태를 역학적으로 분석하였으며, 실천적이고 정책적인 제언을 제시하였다. 분석방법은 자살통계 데이터를 중심으로 첫째, 자살자의 인구사회학적 특성, 및 자살특성을 파악하기 위해 빈도분석 및 기술통계분석을 실시하였고. 둘째, 인구사회학적 특성에 따른 자살특성 차이를 알아보기 위해 교차분석을 실시하였다.

ZnO micro/nanocrystals with different morphologies were synthesized by thermal evaporation of various zinc source materials in an air atmosphere. Zinc acetate, zinc carbonate and zinc iodide were used as the source materials. No catalysts or substrates were used in the synthesis of the ZnO crystals. The scanning electron microscope(SEM) image showed that the morphology of ZnO crystals was strongly dependent on the source materials, which suggests that source material is one of the key factors in controlling the morphology of the obtained ZnO crystals. Tetrapods, nanogranular shaped crystals, spherical particles and crayon-shaped crystals were obtained using different source materials. The X-ray diffraction(XRD) pattern revealed that the all the ZnO crystals had hexagonal wurtzite crystalline structures. An ultraviolet emission was observed in the cathodoluminescence spectrum of the ZnO crystals prepared via thermal evaporation of Zn powder. However, a strong green emission centered at around 500 nm was observed in the cathodoluminescence spectra of the ZnO crystals prepared using zinc salts as the source materials.

An optimum route to fabricate a hybrid-structured W powder composed of nano and micro size powders was investigated. The mixture of nano and micro W powders was prepared by a ball milling and hydrogen reduction process for WO3 and W powders. Microstructural observation for the ball-milled powder mixtures revealed that the nano-sized WO3 particles were homogeneously distributed on the surface of large W powders. The reduction behavior of WO3 powder was analyzed by a temperature programmed reduction method with different heating rates in Ar-10% H2 atmosphere. The activation energies for the reduction of WO3, estimated by the slope of the Kissinger plot from the amount of reaction peak shift with heating rates, were measured as 117.4 kJ/mol and 94.6 kJ/mol depending on reduction steps from WO3 to WO2 and from WO2 to W, respectively. SEM and XRD analysis for the hydrogen-reduced powder mixture showed that the nano-sized W particles were well distributed on the surface of the micro-sized W powders.

The effect of the mixing method on the characteristics of hybrid-structure W powder with nano and micro sizes is investigated. Fine WO3 powders with sizes of ~0.6 μm, prepared by ball milling for 10 h, are mixed with pure W powder with sizes of 12 μm by various mixing process. In the case of simple mixing with ball-milled WO3 and micro sized W powders, WO3 particles are locally present in the form of agglomerates in the surface of large W powders, but in the case of ball milling, a relatively uniform distribution of WO3 particles is exhibited. The microstructural observation reveals that the ball milled WO3 powder, heat-treated at 750oC for 1 h in a hydrogen atmosphere, is fine W particles of ~200 nm or less. The powder mixture prepared by simple mixing and hydrogen reduction exhibits the formation of coarse W particles with agglomeration of the micro sized W powder on the surface. Conversely, in the powder mixture fabricated by ball milling and hydrogen reduction, a uniform distribution of fine W particles forming nano-micro sized hybrid structure is observed.

본 논문에서는 곤충 모방 날갯짓 초소형 비행체에 적용될 끈을 이용한 날갯짓 구동 장치의 구동 원리와 그 최적화 과정이 소개된다. 이 날갯짓 구동 장치는 끈을 이용하여 구조의 경량화와 관성력 감소로 인한 에너지 효율 상승을 목적으로 설계되 었다. 먼저 장력만 전달할 수 있는 끈의 특성을 고려하여 운동학적인 수식이 정립되었으며, 이를 통해 구동 장치의 거동 특 성을 파악할 수 있었다. 이 수식들은 수정된 패턴 검색 최적화 과정에 포함되어 메커니즘의 운동학적 최적화를 가능하게 만 들었다. 최적화된 형상으로 제작된 시제품은 설계의 구동 원리에 맞게 운동하였으며, 그 날갯짓 폭은 목표한 날갯짓 폭을 만 족시켰다. 수치적 시뮬레이션과 실험 결과는 잘 일치하여 제시된 구동 장치가 실제로 활용될 수 있음을 보였다.

By adopting transactional social commerce functions from mobile apps, individuals can sell products and services directly to friends on their contact list. This drives micro entrepreneurs with fewer than ten employees and less than a €2million annual balance (European Union Law, 2013) to become key drivers for economic growth (Paoloni & Dumay, 2011). In particular, individuals aged 18-34 become inspired by images on social networks for clothing and fashion products. Hence, fashion products are popular business items for micro-entrepreneurs. Despite potential benefits for social commerce, micro-fashion entrepreneurs in many countries are still unaware of apps’ use in social commerce to sell products, and to create and manage social capital for their business. This exploratory research aimed to investigate how micro-fashion entrepreneurs adopt transactional-focused social commerce and utilize social capital embedded in network ties for their marketing and sales, based on innovation diffusion and social capital theory. Research questions included: (1) How do micro-fashion entrepreneurs adopt social commerce? (2) How does social capital in network ties contribute to marketing and sales in social commerce? To answer these research questions, qualitative data from phone interviews with 16 micro-fashion entrepreneurs selling fashion products through WeChat in China were analyzed, adopting a thematic analysis. Data indicated micro-fashion entrepreneurs have positive attitudes, based on their experience and knowledge of WeChat. They adopt social commerce to (1) sell products in a new way, (2) connect with customers, and (3) reduce financial risk, while an innovative channel for entrepreneurship. Also, operating a business through WeChat required less time commitment compared with brick and mortar, and online stores, because accessing services like WeChat have payment systems, share images and messages. Free calls and messages are already available. The interview data demonstrated micro-entrepreneurs have an advantage when adopting social network ties in WeChat and implementing social capital embedded in marketing sales networks. Structural, relational, and cognitive capital contribute to micro-entrepreneurs’ marketing and sales interactively. An individual could access target customers, based on networks already established social media platforms and facilitate entrepreneurs’ adoption of social commerce. Also, since trust, shared goals, and languages exist on these network ties, there exists an increase for entrepreneurs’ accessibility to use social commerce to initiate their business, while decreasing business operating expenses, promoting products, and building relationships with customers. In addition, relational capital built by interactions with each customer brings cognitive capital to promote products and strong network ties.

최근 대두된 난분해성 미량오염물질은 일반적인 수처리 공법으로는 제거가 잘 되지 않고 수 ng/L 단위로도 수중생태계와 인간에게 독성을 나타내므로 반드시 처리가 필요하다. 따라서 본 연구에서는 CNT (Carbon nanotube)를 이용하여 중공사막을 제조한 후, 그것을 전극으로 사용하여 미량오염물질을 전기화학적으로 산화 제거하였다. SEM, BET, flux, conductivity 결과를 통해 전극의 특성을 분석하였다. BPA(bisphenol A), Sulfamethoxazole(SMX), N,N-Diethyl-metatoluamide(DEET) 3가지 물질을 제거 대상 미량오염물질로 선정하였고 CHM 산화극 내부로 오염물질이 포함된 물을 흘려 보내주었을 때 5분 만에 100%의 제거효율을 보였다.

This present study deals with the effect of micro-alloying elements and transformation temperature on the correlation of microstructure and tensile properties of low-carbon steels with ferrite-pearlite microstructure. Six kinds of lowcarbon steel specimens were fabricated by adding micro-alloying elements of Nb, Ti and V, and by varying isothermal transformation temperature. Ferrite grain size of the specimens containing mirco-alloying elements was smaller than that of the Base specimens because of pinning effect by the precipitates of carbonitrides at austenite grain boundaries. The pearlite interlamellar spacing and cementite thickness decreased with decreasing transformation temperature, while the pearlite volume fraction was hardly affected by micro-alloying elements and transformation temperature. The room-temperature tensile test results showed that the yield strength increased mostly with decreasing ferrite grain size and elongation was slightly improved as the ferrite grain size and pearlite interlamellar spacing decreased. All the specimens exhibited a discontinuous yielding behavior and the yield point elongation of the Nb4 and TiNbV specimens containing micro-alloying elements was larger than that of the Base specimens, presumably due to repetitive pinning and release of dislocation by the fine precipitates of carbonitrides.

RNA interference (RNAi) has been widely adopted as a primary reverse genetic tool to determine the physiological function of genes of interest. Nevertheless, the lack of optimized RNA delivery method has been a major obstacle for non-model organisms, such as Cimex lectularis. In this study, we have established a RNAi protocol for the silencing of C. lectularis salivary gland-specific cholinesterase (SChE) gene based on micro-injection of double stranded RNA (dsRNA). An aliquot (20 nl) of dsRNA solution (4.5 ng/nl) was injected to body cavity through the arthrodial membrane between metathoracic coxa and sternum of adult females. Observed mortality was less than 5% and at 6-day post injection, while the gene silencing efficiency reached 97~99% at 2-6 day post injection. This result demonstrates the efficacy of injection RNAi via the arthrodial membrane in C. lectularius.

본 연구는 사회 감성(Social emotion)중 공감도 정량화 방법을 제안하고자 한다. 비접촉형 센싱 방법인 인체 미동 기술을 이용하였다. 참가자들은 공감한 그룹과 공감하지 않은 그룹으로 분류하였다. 웹캠(Web-cam)을 이용해 표정 Task를 수행하는 동안 영상의 상반신 데이터를 수집하였다. 수집 된 데이터는 각 주파수 성분 별로 0.5 Hz, 1 Hz, 3 Hz, 5 Hz, 15 Hz로 분류하여 추출하였다. 추출 된 데이터는 움직임의 평균과 변화량, 움직임의 동조현상을 비교하였 다. 그 결과 공감한 그룹의 움직임 평균과 움직임의 변화정도가 낮게 나타났다. 공감하지 못한 그룹의 경우 평균 움직임과 변화정도가 큰 것으로 나타났으며 통계적으로 유의한 차이를 보였다. 또한 공감한 그룹의 두 피험자의 경우 표정 Task를 수행하는 동안 움직임에 동조 현상이 나타나는 것을 확인하였다. 이는 두 사람 간에 공감이 형성 되었을 때 자연스럽게 집중을 하게 되고 그에 따라 움직임에 정도가 차이가 나는 것으로 볼 수 있다. 본 연구는 비접촉 센싱 방법을 통해 공감도 측정 가능성을 확인하는데 의의가 있다.

The oyster mushroom cultivation house typically has multiple layers of growing shelves that cause the disturbance of air circulation inside the mushroom house. Due to this instability in the internal environment, growth distinction occurs according to the area of the growing shelves. It is known that minimal air circulation around the mushroom cap facilitates the metabolism of mushrooms and improves their quality. For the purpose of this study, a CFD analysis FLUENT R16 has been carried out to improve the internal environment uniformity of the oyster mushroom cultivation house. It is found that installing a section of the working passage towards the ceiling is to maintain the internal environment uniformity of the oyster mushroom cultivation house. When all the environment control equipment – including a unit cooler, an inlet fan, an outlet fan, an air circulation fan, and a humidifier – were operated simultaneously, the reported Root Mean Square (RMS) valuation the growing shelves were as follows: velocity 23.86%, temperature 6.08%, and humidity 2.72%. However, when only a unit cooler and an air circulation fan operated, improved RMS values on the growing shelves were reported as follows: velocity 23.54%, temperature 0.51%, and humidity 0.41%. Therefore, in order to maintain the internal environment uniformity of the mushroom cultivation house, it is essential to reduce the overall operating time of the inlet fan, outlet fan, and humidifier, while simultaneously appropriately manage the internal environment by using a unit cooler and an air circulation fan.

역삼투막 운영에 있어서 유기물 오염에 대한 문제들을 해결하기 위해 많은 연구를 하고 있다. 현재 가성소다 (NaOH)를 사용하여 유기물 오염 제거를 하고 있다. 본 연구는 지속적인 막오염 증가 문제를 해결하기 위한 물리/화학적 세정 기법으로서 기존에 사용하던 가성소다와 Micro-bubble를 이용하여 유기물 오염 제거 실험을 수행되었다. 멤브레인 강제 오염 을 위해 Humic acid sodium, Bovine serum albumin, Sodium alginate 약품을 사용하여 유기물 오염을 시켰다. 유기물 오염에 따른 Flux를 관찰하였고, 가성소다와 Micro-bubble를 이용한 유기물 오염 제거 실험은 가성소다로만 사용했을 때보다 향상 된 것을 관찰했다.

The market for Game is gradually expanding every year, but most of games are disappearing. For this Reason, User have chosen games based on external factors, and users have been not able to choose customized games for users. Thus, This study aim to provide customized game contents to users among 6 content (logic, space, word, nature, body, music) by making a immersion evaluation model using the Csikszentmihalyi’s theory of flow and Gardner's theory of multiple intelligence. First, it is assumed that the definition of immersion can be obtained as an arousal which is an axis of the emotion criterion. Then, after learning the arousal classification model based on the head micro-vibration as emotion signal, the immersion evaluation system is verified through the evaluation with the multi-intelligence theory. As a result, the user can be informed of what contents are most immersed in the content, and allow to choose the game suitable for himself.

최근 마이크로 UAV가 대중화 되면서 영상 촬영 기능을 이용하여 지역 정보를 수집하고 분석하려는 다양한 영상처리 방안들이 등장하고 있다. 이러한 영상 처리에는 단순한 파노라믹 영상 제작에서부터 지도 제작을 위한 영상 모자익, 포인트 클라우드 생성을 통한 3D 모델링에 이르기까지 초보적 수준에서 전문적인 분야의 활용 방법들이 일반인들에게 공개 혹은 오픈소스 소프트웨어 형태로 나타나고 있다. 본 연구에서는 상업용으로 보급되고 있는 마이크로 UAV를 이용하여 영상을 촬영하고, 오픈소스 소프트웨어들을 이용하여 영상 처리를 하는 방안들을 분석하였다. 본 연구 결과는 향후 참여형 GIS로서 UAV를 이용하여 공간 정보를 구축하려는 시도에 도움을 줄 것으로 기대한다.

In this study, recrystallization behaviors in the two-phase (α+γ) region of micro-alloyed steels such as Base, Nb, TiNbV and CAlN were investigated in terms of flow stress, microstructure and associated grain boundary characteristics. The flow stress of all specimens reached peak stress and gradually decreased, which means that recrystallization or recovery of proeutectoid deformed ferrite and recovery or transformation to ferrite of deformed austenite occurred by thermal activation. The precipitation of carbide or nitride via the addition of micro-alloying elements, because it reduced prior austenite grain size upon austenitization, promoted transformation of austenite to ferrite and increased flow stress. The strain-induced precipitation under deformation in the two-phase region, on the other hand, increased the flow stress when the micro-alloying elements were dissolved during austenitization. The recrystallization of the Nb specimen was more effectively retarded than that of the TiNbV specimen during deformation in the two-phase region.

Pore filling 기술을 적용한 base 분리막은 평균기공이 5㎛정도를 갖는 대기공 MF막으로써 polyester 재질의 braid로 보강된 PVDF 중공사막을 제조하여 사용하였다. 이렇게 제조된 대기공MF막의 기공내에 기능성이 확보된 친수성 고분자를 채워 넣은 후 화학 반응으로 영구 고정시키거나 유동막으로 고정하여 다양한 기능을 가지는 막을 개발하는 연구를 진행하였다. 본 연구에서는 친수성 고분자중에서 대표적으로 사용되는 poly viny alcohol을 기공에 채워 넣은 후 Aldehyde로 가교시키는 방법으로 pore filling막을 제조하였다. 이렇게 얻어진 분리막은 입자 제거율은 UF정도 수준으로 되고 투과량은 기존UF 분리막에 비해 1.5배 이상 증가하는 것을 확인하였다.