We investigated the microstructure of an FeCrMnNiCo alloy fabricated by spark plasma sintering under different sintering temperatures (1000–1100°C) and times (1–600 s). All sintered alloys consisted of a single face-centered cubic phase. As the sintering time or temperature increased, the grains of the sintered alloys became partially coarse. The formation of Cr7C3 carbide occurred on the surface of the sintered alloys due to carbon diffusion from the graphite crucible. The depth of the layer containing Cr7C3 carbides increased to ~110 μm under severe sintering conditions (1100°C, 60 s). A molten zone was observed on the surface of the alloys sintered at higher temperatures (>1060°C) due to severe carbon diffusion that reduced the melting point of the alloy. The porosity of the sintered alloys decreased with increasing time at 1000°C, but increased at higher temperatures above 1060°C due to melting-induced porosity formation.

The effects of annealing on the microstructure and mechanical properties of Al–Zn–Mg–Cu–Si alloys fabricated by high-energy ball milling (HEBM) and spark plasma sintering (SPS) were investigated. The HEBM-free sintered alloy primarily contained Mg2Si, Q-AlCuMgSi, and Si phases. Meanwhile, the HEBM-sintered alloy contains Mg-free Si and θ-Al2Cu phases due to the formation of MgO, which causes Mg depletion in the Al matrix. Annealing without and with HEBM at 500oC causes partial dissolution and coarsening of the Q-AlCuMgSi and Mg2Si phases in the alloy and dissolution of the θ-Al2Cu phase in the alloy, respectively. In both alloys, a thermally stable α-AlFeSi phase was formed after long-term heat treatment. The grain size of the sintered alloys with and without HEBM increased from 0.5 to 1.0 μm and from 2.9 to 6.3 μm, respectively. The hardness of the sintered alloy increases after annealing for 1 h but decreases significantly after 24 h of annealing. Extending the annealing time to 168 h improved the hardness of the alloy without HEBM but had little effect on the alloy with HEBM. The relationship between the microstructural factors and the hardness of the sintered and annealed alloys is discussed.

PURPOSES : The purpose of this research was to select sites that are appropriate for the storage of individual protective gear that can be used by traffic-controlling police when chemical terrorism occurs. METHODS : A storage facility, which is classified as Class A in the Act on Safety Action at Facilities Vulnerable to Terrorism, is defined for use in the event of soft-target chemical terrorism. Considering the number of controlled intersections and the police stations/substations within a radius of 750 m, the jurisdiction of traffic police and grade of protective gear were identified using ammonia, which has the widest protection boundary among known chemical terrorism substances. RESULTS : The results indicate that mobilization should only occur after the police have put on protective gear at the nearby station, regardless of the police district. Additionally, Class B protective gear should be furnished if there is a police station/substation within the jurisdiction, whereas Class C protective gear should be furnished if there is police station/substation outside of the jurisdiction. CONCLUSIONS : Because it is inefficient to keep protective gear at all police stations/substations, appropriate sites should be selected in accordance with chemical terrorism action strategy.

PURPOSES : The purpose of this research was to present quantitative assessment items for each response phase, and to develop a virtual training method that police can use as a tool to effectively counter chemical terrorism in a crowded facility. METHODS : In this study, domestic and foreign documents related to counterterrorism action and virtual training, as well as a police checklist for counterterrorism simulation, were examined. RESULTS : A new checklist for counterterrorism drills was created; this checklist provides details regarding the tasks, trainees (team), execution, and accuracy at each phase based on the counterterrorism simulation checklist in Annex 4 of the Act on Safety Action at Facilities Vulnerable to Terrorism. CONCLUSIONS : This study demonstrates the necessity of virtual counterterrorism training for police, and provides basic data that can be used for counterterrorism manual development/supplements, and virtual training system development.

오늘날, 의학발달과 생활수준 향상으로 평균 수명이 연장되었으나 노인성 질환은 증가되었다. 노인성 질환이 라고 알려져 있는 대표적인 질환은 치매라고 볼 수 있으나 현대에는 노인뿐 아니라 젊은 층도 치매에서 완전히 벗어날 수 없는 실정이다. 치매는 노화에 따른 뇌 단백질의 변화 및 전두엽의 위축으로 새로운 문제 해결 능력, 문제 처리속도, 기억력 등이 점차 감소됨에 따라오는 질병으로 현존하는 치매 치료제로는 증상완화가 불분명하며 이를 대체할 수 있는 연구가 시급하다. 따라서 본 논문에서는 두뇌 활성화를 통한 인지능력 향상을 기반으로 뇌기능 향상에 도움이 되고자하며 두뇌 훈련 기능성게임을 설계 및 구현하고자 한다. 구현된 기능성 게임은 뇌파측정을 통하여 두뇌 활성화 훈련의 효과성을 검증하고 평가하는 것에 본 논문의 목적이 있다.

큰느타리버섯 수확 후 배지를 이용한 유기퇴비를 제조하여 퇴비 원료로서의 이용가능성에 대해 실험을 진행하였다. 퇴비의 발아능력을 검증하기 위해 오이, 무, 상추, 배추를 파종한 후 발아율과 발아지수를 측정하였으며 미강과 미생물제의 첨가비율이 높을수록 높은 발아율을 나타내는 것을 확인할 수 있었다. 오이와 무의 발아지수는 전체적으로 높았으며, 상추의 경우 SMS 100%와 미강 5% 첨가구만 발아지수 70을 넘었고 배추는 미생물제 5% 첨가구에서 가장 높은 발아지수를 나타내었다. 또한 상추를 이용하여 SMS 상토 제조비율과 생육특성을 조사하기 위해 생육시험용 상토 제조비율은 일반상토 100%와 SMS 10%, SMS 20%, SMS 30%, SMS 50%, SMS 70%, SMS 100%로 제조하여 상추묘를 이식하였다. 먼저 상토재료의 이화학성 분석을 시행하였으며 SMS 첨가량이 높을수록 질소전량이 높아지는 것을 확인할 수 있었다. 하지만 상추의 SMS 처리구와 일반상토에서의 생육정도를 비교하였을 때, 중량은 SMS 10% 43.9 g, 일반상토 46.4 g로 비슷하였으며 엽록소 함량도 SMS 10% 32.8, 일반상토 SMS 10% 32.8로 같았고 나머지도 비슷한 수치를 나타내었으나 총장에서 SMS 10% 14.6 cm, 일반상토 16.8 cm로 일반상토가 더 큰 것으로 확인되었다.