본 연구는 복숭아 주간부 동해 예방을 위한 피복재의 보온성을 평가하기 위해 백색부직포, 황색일반지, 방수패드로 만들어진 피복재의 물리적 특성 및 보온성을 평가하고 실제 겨울철 복숭아 주간부 보온효과를 구명하여 피복재로서의 이용가능성을 검토하기 위해 수행하였다. 세 피복재 중 2겹방수패드 처리가 보온율과 열저항성이 가장 우수하였다. 2겹방수패드 처리의 주간단열효과는 14.09oC 만큼 온도상승을 차단하였고, 야간보온효과는 7.23oC 만큼 온도하강을 차단하여 보온효과가 가장 우수함을 확인하였다. 따라서 방수패드 재질을 보온피복재로 개발·보급할 경우 복숭아 주간부 동해 피해를 경감시키는데 도움을 줄 수 있을 것으로 생각되었다.

OBJECTIVES: Bituminous materials, such as tack coat, are utilized between pavement layers for improving the bond strength in pavement construction sites. The standards regarding the application of bituminous material are not clearly presented in the Korean construction guideline without RS(C)-4. Hence, the objective of this study is to determine the optimum content of bituminous materials by analyzing interlayer shear strength (ISS) from the direct shear tester, which was developed in this research. The shear strength of tack coat was defined with the sort of bituminous materials. METHODS : The mixtures for the shear test were made using marshall mix design. The specimens were vertically and horizontally separated for the direct shear test. The separated specimens were bonded using bituminous material. The objectives of the experiment are to determine the performance of bond and shear properties resulting from slippage, rutting, shovel, and corrugation of asphalt pavements. A machine based on the Louisiana interlayer shear strength tester (LISST) of NCHRP Report-712 was developed to determine the ISS. The applied types of tack coat were RS(C)-4, AP-3, QRS-4, and BD-coat with contents of 0.3ℓ/m2, 0.45ℓ/m2, 0.6ℓ/m2, and 0.8ℓ/m2, respectively. RESULTS: Table 2 gives the results of the direct shear test using the developed shear machine. The BD-coat type indicated the highest average ISS value compared to the others. Between the surface and binder course, optimum tack coat application rates for AP-3, RS(C)-4, QRS-4, and BD-Coat were 0.6ℓ/m2, 0.3ℓ/m2, 0.6ℓ/m2, and 0.45ℓ/m2, respectively. These optimum contents were determined using the ISS value. CONCLUSIONS: The ISS values of AP-3, RS(C)-4, and QRS-4 showed similar tendencies when ISS increased in the range 0.3~0.6ℓ/m2, while ISS decreased when the applied rate exceeded 0.6ℓ/m2. Similarly, the highest ISS value of the BD-coat was observed when the applied rate was 0.45 ℓ/m2. However, shear strength was similar to the maximum value of ISS when the tack-coat application rate of BD-Coat exceeded 0.45ℓ/m2.

The efficiency of the purchasing and procurement logistics is important in automotive industry. The rationalization of production system is directly impact on productivity and quality. For this reason importance of logistics is high. Despite we are continuously making effort, our country are still below the level than developed country on logistics efficiency. Rising labor costs is an important factor in increasing logistics costs. So workforce reduction in logistics department is a large part. We deal with A-company inbound logistics, especially procurement logistics in automotive logistics as research object. So in this study we do research on work load balance about workers. We do research on 1,475 kinds of components in procurement process. We applied work load balance algorithm on chassis, final, sequence, trim warehouses workers. According to number of workers and average M/H, algorithm is applied in two ways. After applied work load balance algorithm we reduced numbers of workers from 28 to 20 and improved worker load balance rate from 47.1% to 93.7%

OBJECTIVES : The objective of this study is to estimate the appropriate storage required for deicing materials in Gangwon-do for successful snow removal operations during the 2018 Pyeongchang Winter Olympic Games. The final estimates of the deicing chemicals can be used by public agencies to aid decision making. METHODS: First, the database that exists in the road snow-removal management system (RSMS) of the Ministry of Land, Infrastructure, and Transport, South Korea was used to determine historical characteristics of snow removal experiences in Gangwon-do. The database includes historical information, including regional and road weather data and number of snow-removal works. Second, both the maximum and the actual amount of storages used for deicing materials in the past three years were analyzed. Lastly, the final estimates of the deicing materials were evaluated using an additional equation. It considers frequency of salt spray application, total administrative road length estimated by road agencies, and number of days required for snow removal works in Gangwon-do. Consequently, the results show that significant differences were not observed between the final estimates and the maximum amount used during the past three years. RESULTS: The final estimates of the deicing materials are almost similar to the maximum amount used during the past three years in Gangwon-do. CONCLUSIONS: The study shows that the estimates of deicing chemicals can be useful when decision making is required for the snowremoval policy.

OBJECTIVES : This is a basic research for the domestic production of airport-airside deicers. This research selected basic materials for deicers appropriate for the pavement of domestic airports by evaluating the deicing performances of basic materials used in internationalstandard airport deicers and their impacts on pavements. METHODS: Laboratory investigation was conducted to evaluate the asphalt surface tensile strength, concrete scaling impact, ASR impact, and deicing performances of sodium formate (NaFm), potassium formate (KFm), sodium acetate (NaAc), and potassium acetate (KAc), which are the basic de-icing materials commonly used at international airports, approved by the FAA. In addition, the analyses were also performed on the airside deicer urea, which is currently used in domestic airports. RESULTS : Laboratory investigation confirmed that sodium formate, potassium formate, sodium acetate, and potassium acetate had superior surface tensile strength, concrete scaling impact, and deicing performance compared to airside urea, but they also had greater impacts on concrete ASR. Among these materials, sodium formate had the best asphalt surface tensile strength, concrete scaling impact, and deicing performance, while also having the greatest impact on ASR; hence, mitigation plans for ASR were needed, if it were to be used as airport-airside deicer. CONCLUSIONS : It is necessary to consider additional additives to prevent ASR of concrete pavements when developing airport-airside deicers using sodium formate, potassium formate, sodium acetate, and potassium acetate.

마이켈슨 간섭계를 이용하여 25 ℃에서 80 ℃까지 온도를 변화시키며 움직이는 간섭무늬의 개수 를 이용하여 투명매질들의 열광학계수를 측정하였다. 파장이 633 nm인 광원에 대해 BK7 광학유리, fused silica, fused quartz의 열광학계수는 각각 2.245×10-6 /K, 8.226×10-6 /K, 8.621×10-6 /K였고, 이는 문헌값과 비교하여 약 ± 2%의 범위 내에서 일치하였다. 붕규산 크라운 유리인 BK7과 SiO2 계열의 시료의 비교를 통해 온도 증가와 함께 유리의 광경로가 변하는 것은 열팽창계수보다는 굴절률변화의 영향을 더 많이 받 는다는 것을 확인할 수 있었다. 또한 동일한 SiO2 구성이라도 온도 증가에 따라 고온 열처리된 fused quart의 굴절률 변화가 fused silica보다 크다는 결과도 얻었다.

본 연구에서는 수처리 분리막의 적용을 위하여 기계적 물성과 내화학성이 우수한 poly(vinylidene fluoride)( PVDF)의 특성평가를 진행하였다. 열유도상분리법을 통한 분리막을 제조하기 위하여 사용된 희석제는 dibutyl-phthalate (DBP)를 사용하였으며, 고분자와 희석제의 비율에 따른 결정화 온도, 녹는점, 흐림점, SEM 이미지 등을 관찰하였다. 고분자 의 함량이 높아질수록 결정화 온도 및 녹는점은 높아졌으며 반대로 흐림점 온도는 낮아짐을 확인하였다. 최종적으로 상평형 도 작도를 통하여 고분자함량 62 wt%, 제막 온도 125°C 이상에서 안정적인 분리막이 제조 가능함을 확인할 수 있었다.

Theories of advanced composite structures are too difficult for such field engineers and some simple methods are necessary. In this paper, Simple method of vibration analysis is presented. This method presented in this paper is studied self-weight and other loads. The result of the 2~3 times iteration is good enough for field engineering purposes. In the case of cantilevered composite materials beams with different cross section, increase of mass near the support does not significantly affect the vibration characteristics. As a calculations of the simple method of vibration analysis for cantilevered composite materials beams with different cross section, it is noted that the result of the second cycle at the point of free end (actually 5L/6 span) is only 2.2% away from the ‘exact’ solution.

Recent decades, maintenance and reconstruction have been paid attention to old buildings. Especially, it has been recognized that seismic retrofit measures are necessary for non-reinforced masonry buildings which are used for prevailing building constructions. However, such applications can be limited due to its excessive costs, long-period, and inherent difficulty in securing construction spaces. For this reason, different reinforcement methods have been proposed by previous researchers in the economic manner. This study carried out an adhesive retrofit material upgrading low workability and excessive costs of existing reinforcement methods and, in turn, verified the level of seismic reinforcement throughout experimental studies. In order for the objectives, masonry walls with an aspect ratio of 1.0 were designed and manufactured. Also, effective parameters which are affected by openings, adhesive material types, the number of reinforcement layers, and lateral load levels were established. Experimental results showed that MW specimens without openings were collapsed for low-seismic resistances resulting from rocking failure modes, while strength and displacement capacities were improved for reinforced openings. Also, R-MWO-3F specimens with opening which was enhanced for three layers of stiffener showed displacement, ductility capacities, and energy dissipating capacities in the stable manner, even satisfying the collapse prevention level proposed in the current seismic codes.

Middle size of membrane retractable roof is under 25m span which consists of various moving systems. Trolley is the system that leads the membrane to parking place, transferring the load from the membrane to structural cable. When membrane closes roof completely, thus, structural behavior of trolley, which may contain various material with different friction coefficients, should be investigated by vertical load. Nummerical simulation of trolley prototypes, in this research, was performed by incrementation of vertical load. Consequently, this paper studied proper friction characteristics and provided the effective inner materials of trolley.

본 연구에서는 한외여과 막을 사용하여 대장균 단독, 대장균 및 Bacillus subtil is 균을 혼합액을 대상으로 제거 효과를 고찰하였으며, 아울러 kaolin, CaCO3 및 urea와 같은 탁도 유발 성분들과 대장균 단독, 대장균 및 Bacillus subtilis 균과의 혼합액에서의 상호작용을 검토하고자 pH 변화, 탁도 제거 효율, urea, kaolin, Ca CO3 제거 효율, 대장균 군 및 Bacillus subtilis 균의 제거 효과를 고찰하였다.

이 논문은 양구 고대리유적의 자료를 중심으로 북한강유역 청동기시대 천전리식 주거의 출현과정을 검 토한 글이다. 이에 앞서 양구 고대리유적에서 조사된 주거지 중 점토다짐구역이 시설되었으나 평면형태상 천전리식 주거와 차이를 보이는 동시에 정형성을 보이는 주거 형태를 고대리식 주거라 명명하였으며, 단계설정과 편년을 통해 고대리식 주거의 시간적 위치를 부여하고 점토다짐구역의 변화가 갖는 의미를 살펴 보았다. 고대리유적은 유물양상을 통해 총 4단계로 구분하였다. 이 중 고대리식 주거는 2단계에 출현해 역삼동식 주거와 공존함과 동시에 천전리식 주거의 이른 형태가 출현한다. 그러나 유물은 여전히 전기 후반의 양상을 보이며 천전리식 주거와 병존하는 3단계에서야 전환기적인 양상의 유물이 확인된다. 이러한 양상 을 종합해 2단계를 전기 후반~중기 전반, 3단계를 중기 전반으로 편년하였고, 고대리식 주거는 천전리식 주거가 정착한 4단계 중기 후반 이후 급격히 소멸한다. 고대리식 주거의 점토다짐구역은 2~3단계를 거치면서 평면형태상 점진적인 변화과정을 겪는다. 특히 주거지 내부 저장공의 위치가 점토다짐구역 외측으로 이동하는 현상과 유물분포양상은 주거의 규모 및 장단비 축소와 점진적인 공간의 기능분화에서 비롯된 점 토다짐구역의 축소와 이동현상으로 파악된다. 이상에서 그간 역삼동식 주거의 영향 하에 자체 발생한 것으로 유추했던 천전리식 주거는 역삼동식-고대리식 ․ 용암리식-천전리식 주거로 이어지는 시간적 ․ 계통적 연결선상에 있으며, 고대리식 주거는 용암 리식 주거와 더불어 천전리식 주거의 출현과정에서 상이한 공간분화를 거친 과도기적 주거형태로 판단된다.

The purpose of this study was to comprehend the procurement system of iron materials and the production process of ironwork in royal tombs constructions in the later Joseon period. For this purpose, sixteen Sanneung-uigwes were analyzed. The following conclusions have been reached through the study. First, it was procuring five types of iron materials in constructions of royal tombs. Sincheol had been supplied up to the mid- 18th century. On the other hand, the amount of jeongcheol was increased rapidly. Because of the procurement system of initial tools was changed from bokjeong(a kind of tribute) to self-production in the Noyaso. Second, the government stockpiles were utilized as much as possible than bokjeong to manage the limited construction period and sudden construction start. Third, before moving the site of tombs, the melting furnace was installed in the Gungisi(armament factory). The amount of the melting furnace was increased from 5 to 8 since producing the initial tools in the Noyaso. Fourth, six kinds of master artisans were worked in the field of producing ironwork. Metal worker was assigned to one person per melting furnace. Fifth, the quality of final iron materials was controlled by use. Since the 19th century, it had been produced enhanced ironwork.

선박의 거주구는 엔진 등 동력원과 거주구 주변의 각종 팬 & 모터에서 발생하는 소음 및 진동이 직접적으로 영향을 미치게 된다. 최근 선원의 근무구조 개선을 위해 국제해사기구에서 2014년 7월 이후 계약된 선박부터 소음규정을 강화하여 강제적용 하도록 하였다. 이 연구에서는 강화된 소음 규정을 만족 할 수 있도록 흡음재 설치에 따른 소음저감 효과에 대해 고찰하였다.

Examining the experiences of seven preservice teachers enrolled in a materials development class, this qualitative case study aimed to explore the way their participation in the materials development process was connected not only to their increased knowledge of and skills in materials development but also to their self-perceived confidence as prospective teachers, contributing to their professional development. The data were collected from multiple reflection papers and were analyzed qualitatively. The findings demonstrated that the materials development class offered the preservice teachers an opportunity to gain insight into the importance of materials in language education and of teachers being knowledgeable and skilled in materials design and development. They also came to a new realization that teachers were active agents who could take initiatives in adapting and developing materials, rather than passive users following the prescribed textbooks. The materials development class further taught them the need to prioritize the goal of promoting successful language learning when developing materials and to take a critical approach in order to counteract any biased cultural representations and their negative consequences on students’ worldviews. Gaining confidence, the preservice teachers spoke highly of their experiential learning in the class as they thought the experience prepared them to become more competent teachers.

『弟子規』는 기초한자 교육 및 인성교육을 위한 童蒙書다. 그 중에서도 한자 학습보다는 윤 리도덕교육에 더 큰 목적을 둔 책이라 할 수 있다. 책은 “總敍”를 포함하여 총 여덟 항목으 로 구성되어 있지만, 주제는 셋으로 요약할 수 있다. 첫째는 부모에 대한 효도와 長者에 대한 공경, 둘째는 사회생활과 처세의 방법, 셋째는 배움과 실천에 관한 내용이다. 대부분 孔子를 대표로 하는 유교사상을 바탕으로 하여, 인간의 기본 도리와 처세법을 자세히 설명해 놓고 있다. 내용 중에는 21세기 현실생활과는 다소 부합되지 않는 낡은 사상과 행동지침이 포함되 어 있어 논란이 되기도 하지만, 전체적으로 보아 전통문화 창달과 인성교육에 유익한 교재라고 판단한 중국 교육계에서는 현재 『弟子規』 閱讀과 교육을 활발하게 전개시키고 있다. 중국 의 ‘國學’ 열기와 함께 인성교재의 핵심으로 활용하고 있는 『弟子規』는 개인주의와 황금만능 주의가 팽배한 현대사회의 아동들에게 전통문화를 이해시키고 바람직한 가치관과 인간성을 회복시키는데 크게 도움이 될 것으로 사료된다. 이런 현상에 대한 치밀한 분석은 우리나라에 서 『四字小學』 등과 같은 교재로 한자 및 인성교육을 시키는데 있어서도 적지 않은 도움이 될 것으로 기대된다.

Railroad ballast materials tend to degrade due to the increase of ballast abrasion and fracture that results in decreasing the capability of shock absorption, interlocking friction, and the resistance to track irregularity. Therefore, it is necessary to establish a methodology to improve or maintain the structural condition of ballast materials which is in the middle of fouling. This study aimed to investigate the effect of reinforcement on the fouled ballast using ballast stabilizer. Field experimental program was conducted to compare the lateral ballast resistance in case of before and after application of ballast stabilizer. A series of laboratory repetitive load triaxial compression test was then performed to compare the accumulated plastic strain in case of before and after application of ballast stabilizer to the ballast materials having a different level of Fouling Index(FI). In the event of application of ballast stabilizer, the accumulated plastic strain decreased by 41.8 and 28.8 percent, respectively, when the FI was 14 and 21, which appears to indicate the ballast stabilizer is effective for the moderate level fouled ballast materials.