In this study, effects of five raw water quality parameters (turbidity, odor compounds caused by algae, filter clogging caused by algae, pH increase caused by algae, and organic matter) on improvements and operations costs of typical water treatment plant (WTP) were estimated. The raw water quality parameters were assumed the worst possible conditions based on the past data and costs were subsequently estimated. Results showed that new water treatment facilities were needed, such as a selective intake system, an advanced water treatment processes, a dual media filter, a carbonation facility, and a re-chlorination facility depending on water quality. Furthermore, changes needed to be made in WTP operations, such as adding powered activated carbon, increasing the injection of chlorine, adding coagulation aid, increasing the discharge of backwashed water, and increasing the operation time of dewatering facilities. Such findings showed that to reliably produce high-quality tap water and reduce water treatment costs, continuous improvements to the quality of water sources are needed.

This study was conducted to find out the change in nutritional components and antioxidant activities of salted Chinese cabbage according to storage temperature and duration using supercooling. Salted Chinese cabbage was investigated every 2 weeks while it was stored at -2℃ and 2℃ for 8 weeks. This was followed by an analysis of freeze dried samples. The analyzed contents were free sugar and free amino acid contents, DPPH and ABTS radical scavenging activity, and TPC and TFC. Free sugar content of salted Chinese cabbage decreased with longer storage duration, while free amino acid did not change significantly. DPPH and ABTS radical scavenging activities did not change significantly with storage duration whereas the TPC and TFC of salted Chinese cabbage stored at -2℃ was higher than that stored at 2℃ for 6 weeks. Therefore, the quality of salted Chinese cabbage was maintained in direct refrigerator storage for a long duration, showing economic and industrial values as a new storage technology.

최근 기후변화 및 국제교역량, 여행객, 외국 이주민 증가 등으로 국내 농작물에 큰 피해를 입힐 수 있는 고위험 식물병의 유입이 꾸준히 증가하고 있다. 검역 대상인 병원체의 수가 증가함에 따라 검역기관 및 연구원의 업무량이 증가하고 있다. 본 연구에서는 지역별 주요 수출대상 과수인 포도, 단감, 감귤의 국내 미기록 병과 원인병원체에 대한 예찰조사를 수행하였다. 이를 위해 전국을 경기-강원, 충청, 전북, 전남, 경북, 경남 그리고 제주 등 7개 권역으로 나누고 각 권역 소재 대학에서 예찰조사를 수행하여 예찰네트워크를 구축하고자 하였다. 포도 대상 병은 모두 4종으로, Pierce’s disease (Xylella fastidiosa), brown rot (Monilinia fructigena), anthracnose (Greeneria uvicola), 그리고 esca (Phaeomoniella chlamydospora)을 조사하였고 경기-강원, 충청도, 전라북도, 그리고 경상북도 권역을 중심으로 각 권역당 3개 지역 그리고 지역당 3개 지점을 두고 조사하였다. 단감은 모두 3종으로, brown spot (Fusicladium levieri), black leaf spot (Adisciso kaki), 그리고 black spot (Phoma kakivora)을 조사하였고 국내 단감 주생산지인 경상남도와 전라남도 권역을 중심으로 각 권역당 3개 지역 그리고 지역당 3개 지점을 두고 조사하였다. 감귤 대상 병은 모두 2종으로, citrus scab (Elsinoë australis), Septoria spot (Septoria citri)을 조사하였고 감귤 주생산지인 제주권역을 중심으로 조사하였다. 모두 9종에 대한 예찰조사는 2019년 4월부터 10월까지 2주간격으로 실시하였다. 예찰조사결과 주요 수출대상 과수인 포도, 단감, 감귤의 국내미기록병 9종에 대한 원인병원체는 발견되지 않았다. 이 연구를 통해 식물병을 조기에 탐지할 수 있는 전국적인 모니터링 시스템을 구축하였고, 국외 외래유입병들의 예찰조사를 위한 지역 거점을 확보하였다고 평가된다.

This study was conducted to provide a basis for raising farm income by increasing the yield and extending the cultivation period by creating an environment where crops can be cultivated normally during high temperatures in summer. The maximum cooling load of the multi-span greenhouse with a floor area of 504 m2 was found to be 462,609 W, and keeping the greenhouse under 32°C without shading the greenhouse at a high temperature, it was necessary to fog spray 471.6 L of water per hour. The automatic fog cooling control device was developed to effectively control the fog device, the flow fan, and the light blocking device constituting the fog cooling system. The fog cooling system showed that the temperature of the greenhouse could be lowered by 6°C than the outside temperature. The relative humidity of the fog-cooled greenhouse was 40-80% during the day, about 20% higher than that of the control greenhouse, and this increase in relative humidity contributed to the growth of cucumbers. The relative humidity of the fog cooling greenhouse during the day was 40-80%, which was about 20% higher than that of the control greenhouse, and this increase in relative humidity contributed to the growth of cucumbers. The yield of cucumbers in the fog-cooled greenhouse was 1.8 times higher in the single-span greenhouse and two times higher in the multi-span greenhouse compared to the control greenhouse.

Various electronic control parts and devices installed in electric vehicles have greatly improved the convenience of occupants, but electromagnetic waves emitted from electronic devices have greatly increased concerns about malfunctions, deterioration of performance, safety accidents, etc. There are two models of analysis. Case A is symmetrical about one axis of rotation. Case B has two axes of rotation. In this study, a flow analysis was conducted to find excellent flow conditions in the mixing process to develop a paint with excellent electromagnetic shielding and thermal insulation performance. The results of the flow analysis are reflected in manufacturing specifications and are intended to be used to develop high-quality systems.

Recently, at-home workouts, which allows people to exercise easily and comfortably at home without going to the gym, has been in the spotlight. Accordingly, a lot of household equipment is produced, but weight exercise equipment is limited in use at home because of its heavy weight or volume. Therefore, this paper proposes a new form of exercise equipment that can be used at home by transforming the exercise equipment used in the fitness center. The proposed mechanism replaces the weight part of the strength exercise device, which is the key to weight control, with an electric motor. Three major muscle exercise instruments (long pull machine, curl cable machine, and let down machine) were analyzed by dynamic analysis using a multipurpose dynamic program (DAFUL). This shows that the proposed equipment can perform various sports. Therefore, the proposed mechanism is expected to be applicable at home, and this study is expected to be rapidly mass-produced by emphasizing practicality.

Recent advances in technology using ultra-thin noble metal film in oxide/metal/oxide structures have attracted attention because this material is a promising alternative to meet the needs of transparent conduction electrodes (TCE). AZO/ Ag/AZO multilayer films are prepared by magnetron sputtering for Cu2ZnSn(S,Se)4 (CZTSSe) of kesterite solar cells. It is shown that the electrical and optical properties of the AZO/Ag/AZO multilayer films can be improved by the very low resistivity and surface plasmon effects due to the deposition of different thicknesses of Ag layer between oxide layers fixed at AZO 30 nm. The AZO/Ag/AZO multilayer films of Ag 15 nm show high mobility of 26.4 cm2/Vs and low resistivity and sheet resistance of 3.58*10−5 Ωcm and 5.0 Ω/sq. Also, the AZO/Ag (15 nm)/AZO multilayer film shows relatively high transmittance of more than 65% in the visible region. Through this, we fabricated CZTSSe thin film solar cells with 7.51% efficiency by improving the short-circuit current density and fill factor to 27.7 mV/cm2 and 62 %, respectively.

1. 개발도상국의 경우, 가치사슬 전반에 걸쳐 제약요인을 가지고 있는 경우가 많다. 이로 인해 가치사슬 일부 단계의 개선만으로는 그 파급효과가 제한적이다. 이로 인해 가치사슬 전반에 걸친 분석과 종합적인 개선 전략의 수립이 필요하다. 2. 선진 공여기관들은 개발도상국의 가치사슬 개선을 위해 여러 가지 분석 틀 및 개선전략 수립 틀을 가지고 가치사슬 사업을 추진하고 있다. 3. 본 연구에서는 한국의 농산물 가치사슬 개선 사업 기획 관리 방안을 제시하였다. 특히, 해당 기획관리 절차를 한국의 대표적인 무상원조 기관인 KOICA의 원조사업 기획 단계에 맞추어 구체적으로 제시하여 실제 현장에서 활용도를 높이고자 하였다. 해당 절차는 1) 대상 품목(혹은 품목군)의 선정, 2) 가치사슬 분석, 3) 개선전략 수립, 4) 기대효과 도출, 5) 성과관리(모니터링 및 평가) 방안의 도출 등으로 구성되었다. 4. 한국의 공여기관들은 이 절차를 바탕으로 농산물 가치사슬 개선 사업의 기획과 시행에 필요한 사항들을 점검 및 확인 할 수 있을 것으로 기대된다. 또한, 현장에서의 활용을 통해 해당 절차를 보다 효과적으로 발전시킬 수 있을 것으로 기대 한다.

PURPOSES : In this paper, pedestrian-oriented time assured traffic operation (POTATO), adopted in Korea at a single crossing pedestrianoriented operating area, is explored and applied to a simulation experiment and test site to verify the operation efficiency. METHODS : Three candidate plans are presented as a method to operate pedestrian-oriented signal operations that can overcome the restrictions on signal controllers in Korea. The selected POTATO and TOD signal operations were compared and analyzed. The delay and pedestrian queues, present length, and number of times were used as comparative indices. RESULTS : Scenario-specific simulations confirmed that the delay, compared to TOD signal operation, was reduced by up to 5 s/ped depending on the vehicle traffic volume and the number of pedestrians. For the vehicle delay, the results increased up to 8.99 s/veh, depending on the traffic volume of the vehicles and pedestrians. As a result of the test site operation, POTATO operation improved by 5.12 s/ped (approximately 46.69% improvement) compared to TOD operation in the hours commuting to school and by 2.84 s/ped in the hours commuting from school (approximately 51.13% improvement). In case of vehicle delay, the delay increased by 2.35 s/veh (approximately 64.39%) in the hours commuting to school and 1.20 s/veh (approximately 21.11%) in the hours commuting from school compared to the TOD operation. CONCLUSIONS : Through simulations and test site pilot operation verifications, the effects of pedestrian delay improvement were more positive if POTATO proposed in this study was low in vehicle traffic.

With few reported cases, cystic hygroma is known to occur mainly in patients under the age of two years. Cystic hygroma can eventuate in any area; however, it mostly occurs in the cervicofacial area. If cystic hygroma occurs in this area, then the lesion may be related to the vital structures. Therefore, a complete surgical resection may be impossible and difficult to perform. This incident affects the high recurrence rate of cystic hygroma. The purpose of this report is to present a case of cystic hygroma occurring on the left side of the neck of a 47-year-old male patient as well as a review of literatures.