2015년부터 2022년도까지 6개목(딱정벌레목, 노린재목, 나비목, 벌목, 파리목, 총채벌레목) 곤충들에 대해서 식물검역현장 검출실적과 국내 보고된 미기록종을 분석하였다. 해당기간 동안 국경검역에서 6개목 곤충은 총 45,084건이 검출되었다. 같은 기간 국내에서는 총 545종이 미기록종 으로 보고되었으며, 이중 9종은 국경검역에서도 검출된 것으로 확인되었다. 검역현장에서는 딱정벌레목, 총채벌레목, 노린재목이 높은 검출률을 보 였으며, 국내 미기록종 중에서는 벌목이 176종으로 가장 많이 보고되었다. 본 연구를 통해 침입압력(국경검역 검출)과 실제 침입(국내 미기록종 발 견) 사이에 비동시성이 확인되었다. 향후 보다 장기적인 분석이 필요할 뿐만 아니라 지속적인 식물검역시스템 개선이 필요할 것으로 판단된다.

High-temperature oxidation of a Ni-based superalloy was analyzed with samples taken from gas turbine blades, where the samples were heat-treated and thermally exposed. The effect of Cr/Ti/Al elements in the alloy on high temperature oxidation was investigated using an optical microscope, SEM/EDS, and TEM. A high-Cr/high-Ti oxide layer was formed on the blade surface under the heat-treated state considered to be the initial stage of high-temperature oxidation. In addition, a PFZ (γ’ precipitate free zone) accompanied by Cr carbide of Cr23C6 and high Cr-Co phase as a kind of TCP precipitation was formed under the surface layer. Pits of several μm depth containing high-Al content oxide was observed at the boundary between the oxide layer and PFZ. However, high temperature oxidation formed on the thermally exposed blade surface consisted of the following steps: ① Ti-oxide formation in the center of the oxide layer, ② Cr-oxide formation surrounding the inner oxide layer, and ③ Al-oxide formation in the pits directly under the Cr oxide layer. It is estimated that the Cr content of Ni-based superalloys improves the oxidation resistance of the alloy by forming dense oxide layer, but produced the σ or μ phase of TCP precipitation with the high-Cr component resulting in material brittleness.

본 연구에서 Nematus tibialis를 국내에서 처음으로 보고한다. 이 종의 사진과 진단, 색 변이, 발육 단계와 분포 등을 제공하였다.

교통수단과 시설의 도입은 인근 지역의 인구구조, 토지이용, 거주민의 통행행태뿐만 아니라 도시 및 지역 공간구조의 변화를 가져온다. 최근 활발하게 도입이 논의되고 있는 복합환승센터는 이용자들의 환승편의를 증진시켜 대중교통수단 이용을 촉진하고, 대규모 상업/문화시설을 함께 입지시켜 쇼핑/여가활동 인구를 수용하는 역할을 담당하고 있어, 역세권 지역의 인구구조 와 토지이용에 복합적인 변화를 가져오고 있다. 따라서 본 연구는 처음으로 건설된 복합환승센터가 위치한 동대구역 역세권 지역을 대상으로 해당 시설의 입지가 유발하는 공간적 변화를 분석하는 것을 목적으로 한다. 격자와 건축물 단위로 구축된 인구와 토지이용 자료를 버퍼(Buffer)와 고리존(Annuli)으로 집계하였고, 이들의 변화가 통계적으로 유의한 지 모수, 비모수 검정을 통해 확인하였 다. 또한, 주성분 분석을 활용하여 인구와 토지이용 각각의 대표적인 변화를 도출하였으며, 국지적 Moran I를 활용한 LISA 분석을 통해 역세권 내에서도 해당 변화들이 집중적으로 나타난 지역을 격자단위로 확인하였다. 그 결과 동대구역 남쪽에서 업무지구로의 변화가 관찰되었으며, 북쪽으로는 단독주택에서 아파트로의 변화가 관찰되었다. 또한, 업무지구로의 변화가 관찰되는 지역에서 20대 인구의 증가가 확인되었으며, 토지이용이 아파트 중심으로 변화하는 지역에서는 전 연령의 인구 증가가 확인되었다.

In this study, defects generated in the YSZ coating layer of the IN738LC turbine blade are investigated using an optical microscope and SEM/EDS. The blade YSZ coating layer is composed of a Y-Zr component top coat layer and a Co component bond coat layer. A large amount of Cr/Ni component that diffused from the base is also measured in the bond coat. The blade hot corrosion is concentrated on the surface of the concave part, accompanied by separation of the coating layer due to the concentration of combustion gas collisions here. In the top coating layer of the blade, cracks occur in the vertical and horizontal directions, along with pits in the top coating layer. Combustion gas components such as Na and S are contained inside the pits and cracks, so it is considered that the pits/cracks are caused by the corrosion of the combustion gases. Also, a thermally grown oxide (TGO) layer of several μm thick composed of Al oxide is observed between the top coat and the bond coat, and a similar inner TGO with a thickness of several μm is also observed between the bond coat and the matrix. A PFZ (precipitate free zone) deficient in γ' (Ni3Al) forms as a band around the TGO, in which the Al component is integrated. Although TGO can resist high temperature corrosion of the top coat, it should also be considered that if its shape is irregular and contains pore defects, it may degrade the blade high temperature creep properties. Compositional and microstructural analysis results for hightemperature corrosion and TGO defects in the blade coating layer used at high temperatures are expected to be applied to sound YSZ coating and blade design technology.

In this study, dual drainage system based runoff model was established for W-drainage area in G-si, and considering the various rainfall characteristics determined using Huff and Mononobe methods, the degree of flooding in the target area was analyzed and the risk was compared and analyzed through the risk matrix method. As a result, the Monobe method compared to the Huff method was analyzed to be suitable analysis for flooding of recent heavy rain, and the validity of the dynamic risk assessment considering the weight of the occurrence probability as the return period was verified through the risk matrix-based analysis. However, since the definition and estimating criteria of the flood risk matrix proposed in this study are based on the return period for extreme rainfall and the depth of flooding according to the results of applying the dual drainage model, there is a limitation in that it is difficult to consider the main factors which are direct impact on inland flooding such as city maintenance and life protection functions. In the future, if various factors affecting inland flood damage are reflected in addition to the amount of flood damage, the flood risk matrix concept proposed in this study can be used as basic information for preparation and prevention of inland flooding, as well as it is judged that it can be considered as a major evaluation item in the selection of the priority management area for sewage maintenance for countermeasures against inland flooding.

The effect of solidification rate on micro-segregation in investment casting of IN738LC superalloy was studied. In Ni-based superalloys, the micro-segregation of solute atoms is formed due to limited diffusion during cast and solidification. The microstructure of cast Ni-based superalloys is largely divided into dendrite core of initial solidification and interdendrite of final solidification. In particular, mosaic shaped eutectic γ/γ’ and carbides are formed in the interdendrite of the final solidification region in some cases. The micro-segregation phenomena formed in regions of dendrite core and interdendrite including eutectic γ/γ’ and carbides were analyzed using OM, SEM/EDS and micro Vickers hardness. As a result of analysis, the lack of (Cr, W) and the accumulation of Ti were measured in the eutectic γ/γ’, and the accumulation of (Cr, Mo) and the lack of Ti were measured in the interdendrite between dendrite and eutectic. Carbides formed in interdendritic region were composed of (Ti, W, Mo, C). The segregation applied to each microstructure is mainly due to the formation of γ’ with Ni3(Al,Ti) composition. The Ni accumulation accompanied by Cr depletion, and the Ti accumulated in the eutectic region as a γ’ forming elements. The Mo tends to diffuse out from the dendrite core to the interdendrite, and the W diffuse out from the interdendrite to the dendrite core. Therefore, the accumulation of Mo in the interdendrite and the deficiency of W occur in the eutectic region located in the interdendrite. Heat treatment makes the degree of the micro-segregation decrease due to the diffusion during solid solution. This study could be applied to the heat treatment technology for the micro-segregation control in cast Ni-based superalloys.

This study attempts to find optimal conditions of the friction coefficient using a discrete element method (DEM) simulation with various friction coefficient conditions and three different grinding media with various ball sizes in a traditional ball mill (TBM). Using ball motion of the DEM simulation are obtained using the optimal friction coefficient compared with actual motion; photographs are taken by the digital camera and the snapshot images are analyzed. In the simulation, the rotation speed of the mill, the materials and velocity of the grinding media, and the friction coefficient between the balls and the wall of the pot are fixed as the actual experimental conditions. We observe the velocity according to the friction coefficient from the DEM simulation. The friction coefficient is found to increase with the velocity. Milling experiments using a traditional ball mill with the same experimental conditions as those of the DEM simulation are conducted to verify the simulated results. In addition, particle morphology change of copper powder is investigated and analyzed using scanning electron microscopy (SEM) for the milling experiment.

Microstructural characteristics of directionally solidified René 80 superalloy are investigated with optical microscope and scanning electron microscope; solidification velocity is found to change from 25 to 200 μm/s under the condition of constant thermal gradient (G) and constant alloy composition (Co). Based on differential scanning calorimetry (DSC) measurement, γ phase (1,322 oC), MC carbide (1,278 oC), γ/γ' eutectic phase (1,202 oC), and γ' precipitate (1,136 oC) are formed sequentially during cooling process. The size of the MC carbide and γ/γ' eutectic phases gradually decrease with increasing solidification velocity, whereas the area fractions of MC carbide and γ/γ' eutectic phase are nearly constant as a function of solidification velocity. It is estimated that the area fractions of MC carbide and γ/γ' eutectic phase are determined not by the solidification velocity but by the alloy composition. Microstructural characteristics of René 80 superalloy after solid solution heat-treatment and primary aging heat-treatment are such that the size and the area fraction of γ' precipitate are nearly constant with solidification velocity and the area fraction of γ/γ' eutectic phase decreases from 1.7 % to 0.955 %, which is also constant regardless of the solidification velocity. However, the size of carbide solely decreases with increasing solidification velocity, which influences the tensile properties at room temperature.

목적 : 본 연구는 병원 중심 의료기관에 종사하는 작업치료사의 근무환경과 직무만족도, 임파워먼트의 관계를 분석하고, 근무환경과 직무만족도의 관계에서 임파워먼트가 매개하는지에 대한 기초자료를 수립하고자 하였다. 연구방법 : 연구기간 및 대상은 11월 10일부터 12월 28일까지 G광역시 병원에 종사하는 작업치료사로, 총 205명이었다. 근무환경, 직무만족도, 임파워먼트의 관련성은 Pearson 상관분석을 실시하였다. 근무환경, 직무만족도, 임파워먼트의 매개효과 검증은 PROCESS macro의 model 4를 적용하여 분석하였다. 간접효과의 유의성 검증은 비모수 재표본(nonparametric resampling)방법으로 알려진 부트스트랩핑(bootstrapping) 을 이용하였다. 결과 : 작업치료사의 근무환경, 임파워먼트, 직무만족도는 모두 유의한 양의 상관관계를 보였고, 근무환경은 직무만족도에 직접적인 영향을 주는 동시에 임파워먼트를 통해 간접적으로 영향을 미쳤다. 결론 : 작업치료사는 지시와 전달 체계에서 벗어나 직업적 특수성을 고려한 수평적이고 지지적인 탄력적 관계의 환경 조성과 자율성과 권한이 보장될 수 있는 임파워먼트의 강화가 상호작용할 때 직무만족의 향상을 넘어 수준 높은 의료서비스를 기대할 수 있을 것이다.

The purpose of this study was to analyze existence of active senior and their sodium intake using the 7th Korea National Health and Nutrition Survey. The samples used for this study were 1,336 males and 1,857 females older than age 45. We used the K-means cluster analysis to distinguish the elderly and one-way analysis of variance (ANOVA) to compare the means statistically among the groups. The analysis confirmed the existence of active seniors and showed different characteristics from other clusters. Also, the sodium intake in active seniors varies with other clusters depending on gender, economic status, social participation and health. In conclusion to reduce the unnecessary social cost of health deterioration of the elderly caused by aging, it is desirable to implement a class-specific policy based on the results of this study.

아고산(sub-alpine)지역의 환경은 척박하고 서식처가 좁지만, 지구환경변화로 인한 북방계 식물의 피난처(refugia)로써 중요한 생태학적 가치를 가지는 지역이다. 한편 황병산(1,407m)은 백두대간보호구역으로 지역적·생태적 가치가 높은 지역이다. 현재 황병산 일대의 목장 및 관광객 유입으로 인하여 산지의 일부가 교란 되고 있어 보전대책 마련이 필요하다. 따라서 본 연구의 목적은 황병산 일대 보전 및 관리방안 마련을 위한 기초자료를 확립하는데 있다. 황병산 일대 해발 1,000m 이상의 지역을 대상으로 총 24개소의 원형방형구를 설치하여 임분조사를 실시하였다. 군집의 유형은 신갈나무-분비나무(군집 1), 신갈나무(군집 2), 분비나무(군집 3)로 분류되었다. 중요치 분석 결과 군집 1은 신갈나무(21.4), 분비나무(19.1), 당단풍나 무(8.2), 피나무(6.0) 등의 순으로 나타났으며, 군집 2 신갈나무(34.9), 분비나무(17.7), 피나무(10.2), 사스래나무(7.2) 등 그리고 군집 3은 분비나무 (40.0), 신갈나무(11.9), 당단풍나무(6.4), 피나무(6.4) 등의 순으로 나타났다. 황병산 분비나무림은 각 임상에 따른 모자이크형 패치형태의 군집구조로 나타나 향후 혼효임분의 동태를 파악하고, 각 우점 군집의 보전을 위하여 버퍼구역을 통한 보전대책 마련이 필요하다.

목적 : 본 연구는 이중과제를 이용한 작업치료 프로그램을 적용하여 경도인지장애 노인의 인지기능 및 보행에 미치는 효과를 알아보고자 하였다. 연구방법 : 연구 대상은 경도인지장애 노인 36명(실험군 18명, 대조군 18명)이었고, 연구 설계는 사전- 사후 통제 집단설계(pretest-posttest control group design)를 적용하였다. 중재는 주 1회 60분씩, 12주, 총 12회기를 실시하였다. 중재 전과 후의 비교를 위해 인지기능은 노인용 로웬스타인 작업치료 인지평가(Loewenstein Occupational Therapy Cognitive Assessment-Geriatric Population; LOTCA-G)를, 보행은 일어서서 걷기 검사(Timed Up and Go; TUG)를 사용하였다. 결과 : 이중과제를 이용한 작업치료 프로그램은 실험군의 인지기능과 보행을 향상시켰고 단일과제활동 프로그램에 참여한 대조군과 유의한 차이를 보였다. 결론 : 본 연구의 이중과제를 이용한 작업치료 프로그램은 경도인지장애 노인의 인지기능 및 보행을 향상 시키는 프로그램으로서의 가치 및 효용성을 확인하였기에, 경도인지장애 노인의 치매예방을 위한 적극적인 중재 프로그램으로 제안한다.

Objectives of this study were to identify the hotspot for displacement of the on-line water quality sensors, in order to detect illicit discharge of untreated wastewater. A total of twenty-six water quality parameters were measured in sewer networks of the industrial complex located in Daejeon city as a test-bed site of this study. For the water qualities measured on a daily basis by 2-hour interval, the self-organizing maps(SOMs), one of the artificial neural networks(ANNs), were applied to classify the catchments to the clusters in accordance with patterns of water qualities discharged, and to determine the hotspot for priority sensor allocation in the study. The results revealed that the catchments were classified into four clusters in terms of extent of water qualities, in which the grouping were validated by the Euclidean distance and Davies-Bouldin index. Of the on-line sensors, total organic carbon(TOC) sensor, selected to be suitable for organic pollutants monitoring, would be effective to be allocated in D and a part of E catchments. Pb sensor, of heavy metals, would be suitable to be displaced in A and a part of B catchments.

The microstructure, hardness, and wear behaviors of a High Velocity Oxygen Fuel(HVOF) sprayed WC-CoFe coating are comparatively investigated before and after laser heat treatments of the coating surface. During the spraying, the binder metal is melted and a small portion of WC is decomposed to W2C. A porous coating is formed by evolution of carbon oxide gases formed by the reaction of the free carbon and the sprayed oxygen gas. The laser heat treatment eliminates the porosity and provides a more densified microstructure. After laser heat treatment, the porosity in the coating layer decreases from 1.7% to 1.2 and the coating thickness decreases from 150 μm to 100 μm. The surface hardness increases from 1440 Hv to 1117 Hv. In the wear test, the friction coefficient of coating decreases from 0.45 to 0.32 and the wear resistance is improved by the laser heat treatment. The improvement is likely due to the formation of oxide tribofilms.