PURPOSES : This study proposes brief guidelines for traffic engineers in the field to refer to when operating tram priority signals based on the "early green" and "green extension" methods. METHODS : A set of VISSIM simulation analyses was conducted considering various traffic and control conditions in a hypothetical corridor consisting of two signalized intersections. The traffic conditions were varied at five different levels. The control conditions were varied at twenty-five levels by changing the tram priority traffic signal control parameters, i.e., the early green unit time and green extension unit time. A total of 125 simulation runs were from these combinations. A set of optimal signal timings for ordinary non-tram vehicles was prepared with TRANSYT-7F and implemented for the simulation. A tram priority signal control module based on VISVAP was exclusively developed for this study. RESULTS : As expected, no specific trend was found in the relationship between the two tram priority control parameters (early green time and green extension time). However, a trend was observed when assuming that the early green and green extension operations were mutually exclusive. Specifically, an inverse trend appeared between the tram priority control parameter values and level of congestion according to the performance measure (average network delay). CONCLUSIONS : For the early green control parameters, it is better to provide six seconds when undersaturated and four seconds when near-saturated. For the green extension control parameter, four seconds is suitable.

본 연구는 대학의 피부미용 전공교육에서 문제중심학습(PBL) 적용에 따른 학습효과를 알아보 고, 피부미용 교육경쟁력을 강화할 수 있는 교수·학습방법 개발을 위한 기초자료 제공을 목적으로 하였다. 이에 본 연구는 H대학교에 개설된 피부미용 전공 교과목인 “동양요법” 수강 학생 15명을 대상으로 PBL 수업을 적용하여 실증적 교육효과 분석을 실시하였다. 그 결과 PBL 수업을 참여한 후 학습자들의 문제해 결 능력과 협력적 자기효능감의 평균값이 상승하여 유의미한 차이를 보였으며, 이에 따라 PBL 교수학습법 의 효과성이 확인되어 피부미용 교육 현장에서 학습자들의 문제해결 능력과 협력적 자기효능감 상승을 위 한 효과적인 교수학습법으로 제안하는 바이다.

In existing ceramic mold manufacturing processes, inorganic binder systems (Si-Na, two-component system) are applied to ensure the effective firing strength of the ceramic mold and core. These inorganic binder systems makes it possible to manufacture a ceramic mold and core with high dimensional stability and effective strength. However, as in general sand casting processes, when molten metal is injected at room temperature, there is a limit to the production of thin or complex castings due to reduced fluidity caused by the rapid cooling of the molten metal. In addition, because sodium silicate generated through the vitrification reaction of the inorganic binder is converted into a liquid phase at a temperature of 1,000 °C. or higher, it is somewhat difficult to manufacture parts through high-temperature casting. Therefore, in this study, a high-strength ceramic mold and core test piece with effective strength at high temperature was produced by applying a Si-Na-Ti three-component inorganic binder. The starting particles were coated with binary and ternary inorganic binders and mixed with an organic binder to prepare a molded body, and then heat-treated at 1,000/1,350/1,500 °C to prepare a fired body. In the sample where the two-component inorganic binder was applied, the glass was liquefied at a temperature of 1,000 °C or higher, and the strength decreased. However, the firing strength of the ceramic mold sample containing the three-component inorganic binder was improved, and it was confirmed that it was possible to manufacture a ceramic mold and core via high temperature casting.

해상공사에서 발생하는 부유사는 해수의 탁도를 증가시키고 광량을 감소시켜 해양생물에 악영향을 미치므로 해양환경영향평 가에서 중요한 요소이다. 하지만 평가에 적용되는 인자에 대한 공식적인 자료의 부족과 평가자의 능력에 따라 그 영향이 달리 평가되고 있다. 따라서 본 연구에서는 해역이용영향평가센터에서 검토한 3년간(2012–2014)의 매립, 준설, 외곽시설물 설치 등 총 58건 사업에 대한 부유사 확산 평가에 대한 실태를 진단하고 개선방안을 제시하였다. 개선방안 제시를 위해 4가지의 평가지표(격자체계의 적정성, 원단위의 적정성, 대표입경 및 침강속도의 적정성)를 적용하였다. 각 항목별 신뢰도에 평균점수 분석결과, 격자체계는 25점, 원단위는 60점, 대표입 경은 34점 그리고 침강속도는 17점으로 평가항목에 대한 개선방안이 필요한 것으로 나타났다. 본 연구에서는 부유사 확산 평가상태에 대 한 진단 및 신뢰도 평가 결과를 활용하여 부유사 확산예측에 대한 개선방안을 제안하였다. 먼저, 부유사 발생원단위 및 대표입경별 침강 속도에 대한 공신력 있는 값이 가이드라인을 통해 제공해야 한다. 그리고 실무에선 신뢰성 향상을 위해 격자체계의 적정성과 결과의 검 증을 철저히 해야 한다.

최근 비풀러렌 전자수용체 소재 개발로 태양전지 및 광검출기 등 유기광다이오드 분야의 상당한 진보를 나타내고 있 다. 비풀러렌 소재의 자유로운 구조 개질 가능성을 바탕으로 흡광대역 자유 제어가 가능한 장점으로, 기존 태양전지 에서 구현이 힘들었던 고성능 반투명 태양전지, 실내 저조도 태양전지, 파장선택적 광검출기 등 다양한 응용을 가능 하게 한다. 본 리뷰에서는 유기태양전지를 비롯한 유기광다이오드의 광활성층에 활용되는 유기반도체 소재의 최신 연 구동향에 대해 다루고자 한다.

유선 및 도선 중 선박길이 12미터 미만인 소형선박은 선박안전법에 따른 복원성 기준 적용이 면제되며, 유선 및 도선 사업법에 따라 승객 및 선원이 탑승 가능한 면적을 고려하여 승선정원을 정하고 있다. 이러한 유선 및 도선 중에서는 건조 이후 차양의 설치 등 복 원성에 영향을 미치는 상부 구조물을 설치하는 사례도 적지 않다. 이에 본 연구에서는 상부 구조물을 설치한 도선에서 실제 발생한 전복 사고의 사례를 바탕으로 해당 도선의 복원성을 추정하여 사고 원인을 분석하고자 하였다. 분석 결과, 승선정원을 초과한 상태에서 승객들 이 동시에 하선하고자 기립하여 복원성이 악화된 것으로 나타났으나, 해당 도선이 승선정원을 준수하더라도 한쪽 현의 승객들이 기립하 면 횡경사에 의한 전복의 가능성이 존재하였다. 따라서, 보다 안전한 유선 및 도선사업을 위하여 선박길이 12미터 미만의 유선 및 도선에 대하여 건조 및 개조 시 실선 복원성 시험에 의한 승선정원 산출, 승선정원의 총중량 한곗값 제시 등을 개선방안으로 제시하였다.

This study examined the quality characteristics and antioxidant properties of fruit and vegetable jellies mixed with Boswellia. Jellies were prepared with 0, 2, 4, 6, and 8% Boswellia, sugar and konjac. As a result, the pH of Boswellia jellies decreased to 5.19, 5.05, 4.94, and 4.84, respectively (p<0.001). Their L-value, a-value, b-value, and hardness increased significantly with increasing levels of added Boswellia (p<0.001), while individual phenolic compounds increased significantly with increasing levels of added Boswellia. Free sugars and organic acid contents had the highest bw10. The total phenolic compounds had the highest BW5 (112.9 mg TAE/g), BW10 (99.41 mg TAE/ g), and while the ABTS activities showed higher values than the control group. Overall, Boswellia can be used to produce high-quality jelly, which is expected to help develop excellent functional jelly products.

PURPOSES : In this study, the amount of core stone breaking in the size of boulders by excavator braker work was analyzed quantitatively through on-site test construction. In addition, the factors affecting workload were studied. METHODS : In the field test, 30 core stones of boulder sizes (1–4 m3) that appeared during earthworks, such as road construction and site construction, were collected from three locations, and the rock breaking work was carried out simultaneously using three excavator breakers(1.0-m3 volume). During the core stone breaking, progress was analyzed through video recordings. RESULTS : After the completion of rock breaking, the amount of breaking work was analyzed by direct loading and weighing using a 15- ton dump truck. As a result of the test construction, there was a significant difference in the amount of work completed per hour. CONCLUSIONS : It was found that the results were greatly affected by not only the performance of the excavator braker equipment, but also the skill of the driver and the size of the core stones.

이 논문은 조선시대 수장과 수장가에 대해 그동안 단편적으로 논의되었던 수장가의 개념과 수집행위로부터 파생된 여러 양상을 종합적으로 정리하고 그 의미를 탐색하는데 중점을 둔 것이 다. 조선시대 사람들이 생각한 진정한 수장가란, 수집을 이용해 재력이나 인맥을 과시하는 사람 이 아닌 작품의 가치를 분별할 줄 아는 진정한 감식가이자 작품의 훼손을 방지하는 보존가로 해 석된다. 당시 수장가들은 작품의 보전을 위해 별도의 보관처인 장서루나 수장처를 마련하였고, 수장인을 찍거나 수장목록을 작성해 수장품의 소유를 증명하고 출납과 현황을 파악하였다. 이러 한 현존 수장목록은 개인의 취미를 보여주는 사례를 넘어서 한 시대의 지성사와 예술사의 흐름을 보여주는 또 다른 자료라는 점에서 미술사적 의의가 있다.

PURPOSES : The objective of this study is to evaluate the effectiveness of spraying dust suppressants in relation to the condition of road pavement in South Korea and to develop an optimal management method by continuously measuring re-suspended dust concentrations using a vehicle-based measurement. METHODS : Indoor experiments were conducted to select suppressants suitable for local conditions to reduce reducing road dust, which were identified through literature review. Data collection followed the evaluation method by selecting a section sprayed with dust suppressants and a non-sprayed section within the service road. RESULTS : The BPT experiment is designed to ensure the skid resistance of the road when dust suppressants are sprayed on the road. The Environmental toxic tests for PM10, HCHO, and TVOC all met the daily indoor air quality standards recommended in Korea for determining stability. Comparison of PM10 contents before and after spraying of the test road with dust suppressants and the non-sprayed section, it was confirmed that the dust suspended by the external environment may be reduced, but the amount of dust remaining on the road may increase. After 4 hours, when the water had evaporated, the dust suppressants remained effective and lasted for two-days. CONCLUSIONS : The concentration of fine dust in South Korea varies with the average duration of highly concentrated fine dust being 26.5 h nationwide, 20.5 h in the Seoul metropolitan area, and 25.1 h in Gyeonggi-province, suggesting a duration of one to two days. Thus, the fine dust problem can be solved by using dust suppressants.

Recently, the purchase of fresh-cut produce and meal kits has increased. Ready-to-eat (RTE) fresh-cut products have potentially hazard of cross-contamination of various microorganisms in the processes of peeling, slicing, dicing, and shredding. There are frequent cases of protozoa food poisoning, such as Cyclospora and Cryptosporidium, caused by fresh-cut products. The objective of the study is to investigate the microbiological qualities of various types of RTE fresh-cut products in the domestic on/offline markets. RTE fresh-cut fruits cup (n=100), fresh-cut vegetables (n=50), and vegetables in meal kits (Vietnamese spring rolls and white radish rolls kits, n=50) were seasonally analyzed. The contamination levels of hygienic indicator organisms, yeast and mold (YM), and foodborne pathogens (Bacillus cereus, Staphylococcus aureus, Listeria monocytogenes, Salmonella spp., and Escherichia coli O157:H7) were monitored. Overall, the lowest microbiological qualities of meal kits vegetables were observed, followed by RTE fresh-cut fruits cup and fresh-cut vegetables. Contamination levels of total aerobic bacteria, coliforms, and YM in meal kits vegetables were 5.91, 3.90, and 4.71 logs CFU/g, respectively. From the qualitative analysis, 6 out of 200 RTE fresh-cut products (3%) returned positive result for S. aureus. From the quantitative analysis, the contamination levels of S. aureus in purple cabbage from a meal-kit and fresh-cut pineapple were below the acceptable limit (100 CFU/g). Staphylococcus enterotoxin seg and sei genes were detected in RTE fresh-cut celery and red cabbage from meal-kits, respectively. S. aureus contamination must be carefully controlled during the manufacturing processes of RTE fresh-cut products. Neither Cyclospora cayetanensis nor Cryptosporidium parvum was detected in the samples of RTE fresh-cut products and vegetables from meal-kits from the Korean retail markets.