• Elastomers and Composites
• /
• v.37 no.4
• /
• pp.244-257
• /
• 2002

A thermotropic liquid crystalline polymer(TLCP) which has flexible butylene/hexylene spacers in the main chain and a triad aromatic ester type mesogenic unit containing a naphthyl group was prepared by solution polycondensation. The in-situ composites based on poly(ethylene 2,6-naphthalate) (PEN) and a thermotropic liquid crystalline polymer(TLCP) were prepared and melt spun at different TLCP contents and different draw ratios to produce monofilaments. Blends of the TLCP with PEN were investigated in terms of thermal, mechanical properties and morphology. The TLCP synthesized showed nematic mesophasic behavior and its transition temperature to isotropic melt from mesophase was 249℃. The blends showed well dispersed TLCP phases in the PEN matrix without macroscopic phase separation. Inclusion of TLCP in the blends decreased the cold crystallization temperature of PEN in the blend, therefore, the TLCP acts as a nucleating agent in the blend and showed good interfacial adhesion between the dispersed LCP phases and PEN matrix with domain sizes 40~50 nm in diameter and well developed fibrillation in the monofilaments. The TLCP acted effectively as a reinforcing material in the PEN matrix at the 10wt% level, it led to an increase of initial modulus up to 270% and tensile strength by 235%, while the elongation rate increasing with higher draw ratios.

• Journal of Korean Port Research
• /
• v.4 no.1
• /
• pp.33-43
• /
• 1990

우리나라에서는 70년대 이후 컨테이너 수송체계가 도입되어 운영되어 왔으나 차량의 급격한 증가와 더불어 컨테이너 수송체계는 도시교통에 있어서 많은 문제를 야기시키는 것으로 논란이 되고 있다. 특히, 부산항은 우리나라 최대의 국제 무역항으로써 전 컨테이너 수송화물의 90%이상을 처리하고 있고, 또한 수출입항으로서 제 역할을 다하고 있으나 낮은 도로율(12.45%)과 산재해 있는 30여개의 Off-Dock CY로 인해서 도심을 통과하는 컨테이너 수송차량은 많은 교통문제를 유발시키고 있다. 본 연구는 1) 부산시에 산재해 있는 30여개의 Off-Dock CY에 이르는 주요 도로상에서 컨테이너 수송량의 신간별 분포에 따라 컨테이너의 운행시간대를 첨두 시간대, 비첨두 시간대 및 심야 시간대로 분류하여 각 시간대별 평균 수송 시간 및 교통 체증으로 인한 수송 지체수준을 확인하였고, 2) 컨테이너 전용부두로 부터 Off-Dock CY에 이르는 도시 고속도로 및 주요간선도로상에서의 수송시간 및 수송 지체수준을 비교 분석하였으며, 3) 마지막으로, 효율적인 컨테이너 수송체계를 위한 최적 수송시간대 및 도로체계를 제시할 수 있었다. 특히, 컨테이너 수송시간 및 지체수준은 각 운행 시간대에 따라 현저한 차이를 보이고 있었는데, 심야 시간대를 이용하여 컨테이너 수송을 할 경우에는 다른 시간대에 비하여 50%정도의 수송시간 절감효과를 기대할 수 있었으며, 도시 고속도로를 이용할 경우에는 도시 간선도로에 비하여 30%정도의 수송시간을 절약할 수 있었다. 따라서 도시지역의 교통체중을 완화시키기 위해서 심야 시간대에 보다 많은 컨테이너 수송차량이 이용할 수 있는 컨테이너 수송체계가 확립되어야 하고, 산재해 있는 Off-Dock CY를 몇개의 ODCY그룹이나 단지까지 컨테이너 전용 고속도로의 건설이 바람직하고 생각된다.리구에서 조사한 결과 $10^{-3}$ M MGBG 단독 처리구에서 에틸렌 생성량이 가장 높았으며, spermidine과 spermine의 함량은 가장 낮았다. 부정근 형성능이 다소 회복된 $10^{-3}$ M MGBG+ $10^{-5}$M spermine 혼합처리구에서의 에틸렌 생성량은 대조구보다는 다소 높게 나타났다. 부정근 회복능이 가장 높았던 $10^{-3}$ M MGBG+ $10^{-5}$ M spermine + $10^{-4}$ M Cocl$_2$ 혼합처리구에서 에틸렌 생성량은 가장 낮게 나타났으며, polyamine 함량은 가장 높게 나타났다.(Cyperaceae), 명아주과(Chenopodiaceae) 같은 풀들이 하구언(estuary)의 해안가에 주로 서식하였던 것으로 나타났다. 이 시기동안에 해양성조류인 와편모류와 담수성 조류가 동시에 다양하게 산출되는 것은 하구언 퇴적환경이었음을 잘 지시해 준다. 제II화분대(고도, 43.72{\sim}3.36\;m$)가 시작되면서 혼합림은 침엽수림으로 바뀌었으며, 낙엽활엽수들의 서식지가 2엽소나무로 대치되면서 침엽수가 주요 수종을 이루었던 것으로 나타났다. 아마도 이런 산림형태는 자연 기후환경변화 뿐만 아니라 인간간섭에 의해 나타난 결과로 생각된다. 이 시기에 경작식물인 벼과(Gramineae), 옥수수(Zea), 메밀(Fagopyrum)과 논밭의 뚝 등지 에서 서식하는 돼지풀(Ambrosia) 등이 처음으로 산출되는 것으로 보아 인간간섭이 행해졌음을 잘 뒷 받침해준다. 또한 담수성 조류는 변함없이 산출되는 반면, 해양성조류인 와편모류가 산출되지 않는 것으로 보아 해안환경에서 다소 멀 어진

• The Journal of the Convergence on Culture Technology
• /
• v.9 no.2
• /
• pp.99-104
• /
• 2023

The purpose of this study was to examine the effect of children's academic stress on school adaptation and to verify whether ego-resilience plays a mediating role in the relationship between academic stress and school adaptation. Based on the data from the 12th year of the Korean Children's Panel (2019), the general characteristics of the main subjects and the mean, standard deviation, skewness and kurtosis of the main variables were confirmed through basic statistical analysis, and correlation analysis was conducted between variables. In addition, to examine whether ego-resilience mediated the effect of academic stress on school adaptation, a three-step regression analysis was conducted following the procedure of Baron and Kenny. The results of this study were as follows. First, it was found that children's academic stress, school adaptation, and ego resilience were all significantly correlated. The higher the academic stress, the lower the ego-resilience and school adaptability. Second, it was confirmed that ego-resilience has a partial mediating effect in the relationship between children's academic stress and school adjustment. Ego resilience in the academic stress situation means that it acts as an important mediating factor to flexibly adapt to school life by objectively grasping and coping with the stress situation. Therefore, we need to recognize the need for flexible and resilient individual characteristics so that children can reduce academic stress and adapt well to school life, and seek active interest and intervention plans.

• The Korean Journal of Zoology
• /
• v.28 no.1
• /
• pp.44-59
• /
• 1985

The epithelium of the hindgut in the german cockroach, Blattella germanica Linne, was observed with electron microscope. The epithelium of the ileum, which is located at the anterior hindgut, is composed of a single layer of squamous and cuboidal cells. The liminal surface of the epithelium is lined with the cuticular intima. The epithelial cells contain cell organelles expected to be found in absorptive cells, and some epithelial cells have numerous lamelated crystals, the "spherites". The rectal epithelium of posterior hindgut is composed of rectal pads which are covered with cuticular intima on the luminal side. The rectal pads are composed of columnar absorptive cells and basal cells. The apical plasma membrane of columnar cell is made of microvilli, where mitochondria associated with some of the microvilli. The lateral plasma membrane is highly infolded and space is an uniform width of approximately 200$\\AA$. Well developed mitochondria are found closely associated with the infoldings and this is referred to as the "mitochondrial-scalariform complex". A septate junction is found near the apical zone between the columnar absorptive cells, whereas many desmosomes and intercellular spaces are formed between the columnar cells. Basal cells are bowl-shaped where the convex surface is inlaid into the basal surface of the columnar cells while the concave surface faces the basal lamina. The cytoplasm of the basal cell is electron dense and contains well developed cell organelles. The basal sheath is located between the basal membrane and basal lamina, providing barrier between the epithelium and the hemolymph. The epithelium is surrounded by the subepithelial space and muscles. The subepithelial space, which is composed of fibrous connective tissue, is innervated by many tracheoles and axons.

• Journal of Korea Entertainment Industry Association
• /
• v.13 no.7
• /
• pp.183-192
• /
• 2019

This study studied five major films from the 1980s to the 2000s when Philip Glass's minimal music was used, and studied the aesthetic and functional meaning of the minimal music. Minimal music has a repetitive rhythm and is understood to be aesthetically monotonous, to avoid a particular purpose, or as an expression of moveless. On the one hand, it can mean infinite persistence by repetitive rhythms, or sometimes repetition with subtle changes. The functions of film music were applied as the function of film music common to many theorists. As a result of the analysis of the music in five films, the aesthetic meaning of Philip Glass's minimal music was most relevant to the characteristics of the film story, and the functional meaning of the film music was determined by the structure, form, and genre of the film. Therefore, the theme of the film and the contents of the story played an important role in the aesthetic interpretation of film music with repetitive rhythm characteristics. And the elements of the plot such as the structure, form, and genre of the film are thought to have had a significant effect on the functional interpretation of the film music. The aesthetic value of the film music is closely related to the story of the film, and the functional meaning of the film music is interpreted as determined by the formal elements of the film.

• Journal of Appropriate Technology
• /
• v.5 no.2
• /
• pp.62-69
• /
• 2019

Supplying stable electric power is one of the important objectives of the Official Development Assistance (ODA) because it is strongly related with improving living standards and income levels in the region. However, rural areas in many developing countries are not properly connected to national power grids, and even areas connected to national power grids are frequently blacked out due to limitations in power capacity. These lack of electric power is a major obstacle to improving income levels and improving living standards in those areas. The Korea-Tanzania Innovative and Energy Center (iTEC), which was established by Seoul National University in cooperation with the Nelson-Mandela Africa Institute of Science and Technology and Technology (NM-AIST) try to build a small solar power plant using a smart-off grid in rural area of Tanzania, where there is no electricity. 10 kW and 7 kW solar power plants are built in Mkalama Village in Kilimanajaro Region and Ngurdoto Village in Arusha Region to provide power to about 50 households each. In addition, smart monitoring systems were installed to collect data about status of power system and power consumption of each house. iTEC seeks for sustainable improvement the income level and quality of life of rural residents in developing countries through the construction of small solar power plants using smart-off grid, and the implementation of various connected projects.

• Asia Marketing Journal
• /
• v.11 no.1
• /
• pp.73-92
• /
• 2009

Consumers influence other consumers' brand choice behavior by delivering a variety of objective or subjective information on a particular product, which is called WOM (Word-Of-Mouth) activities. For WOM activities, WOM senders should choose messages to deliver to other consumers. We classify the contents of the messages a consumer chooses for WOM delivery into two categories: Subjective (positive or negative) evaluation and objective information on products. In our study, we regard WOM senders' activities as a choice behavior and introduce a choice model to study the relationship between the choice of different WOM information (WOM with positive or negative subjective evaluation and WOM with objective information) and its influencing factors (information sources and consumer characteristics) by developing two bivariate Probit models. In order to consider the mediating effects of WOM senders' product involvement, product attitude, and their characteristics (gender and age), we develop three second-level models for the propagation of positive evaluations, of negative evaluations, and of objective information on products in an hierarchical Bayesian modeling framework. Our empirical results show that WOM senders' information choice behavior differs according to the types of information sources. The effects of information sources on WOM activities differ according to the types of WOM messages (subjective evaluation (positive or negative) and objective information). Therefore, our study concludes that WOM activities can be partially managed with effective communication plans influencing on consumers' WOM message choice behavior. The empirical results provide some guidelines for consumers' propagation of information on products companies want.

• Asia Marketing Journal
• /
• v.11 no.3
• /
• pp.91-124
• /
• 2009

With the intensity of competition and the standardization of technical attributes in telecommunications service market increasing, differentiated activity and customer experience in service encounter is regarded as an important means for creating customer value, however, there is a dearth of good literature examining what MOT activity is composed of according to consumption chain, and how service quality of MOT has influenced customer performance. Especially there exist various services across different phase of Product life cycle(PLC) in household telecommunication service market, customer requirement for MOT might depend on whether its phase is introduction-growth stage or maturity-decline stage, the empirical study is completely lacking. This study classified household telecommunication services into two types by PLC, VOIP and IPTV as Introduction-growth stage services, Internet and PSTN as maturity-decline stage service, and investigated whether there exists a gap between service types in how consumer have experienced MOT, what they consider as important and the relative importance of quality dimension how service quality of MOT has influence on consumer performance. The empirical result from 858 participants shows that there is a difference in consumer experience and requirements across different phases of the PLC, tangibles and assurance are regarded as the most important service quality factors which have a positive influence on customer performance (consumer satisfaction, repurchase intention and word of mouth) at the introduction-growth stage, whereas, reliability, empathy and interactivity are at the maturity-decline stage. Finally, managerial implication is made, limitation is clarified and a direction for further studies is suggested.

• Asia Marketing Journal
• /
• v.8 no.1
• /
• pp.49-76
• /
• 2006

This study investigates the effect of market orientation of knowledge-based service suppliers on the sourcing process of service recipients. Focusing on a dyadic relationship between a supplier and a buyer, this study proposed a conceptual model of market orientation incorporating the antecedents and consequences of market orientation. This study empirically tested research hypotheses delineated from the conceptual framework. The present study revealed that the impact on the buyer's performance of the supplier's customer and competitor orientation turned out to be more influential than that of inter-departmental cooperation. Also these two dimensions of customer and competitor orientation played a positive role in reducing buyer's perceived risk and uncertainty related to the evaluation of services out-sourced. Interestingly enough, the supplier's perceived importance on the distance between the buyer and supplier remains important especially when the degree of buyer's market orientation is high. This finding is somewhat contrary to the fact that the geographic location of the buyer becomes less important for the internet-based B2B service providers. Based on the findings, this study suggested managerial implications and broadened the scope of academic research in the field of business services. Future research directions and the limitations of this study are also discussed.

• Journal of Korean Library and Information Science Society
• /
• v.54 no.3
• /
• pp.295-320
• /
• 2023

Jeongseon-gun has the SaBuk Public Library, 17 small libraries, and the Jeongseon Educational Library. In 2023, with the completion of the Jeongseon County Public Library, there is a need to establish innovative library policy strategies that consider balanced development by region. The primary goal of this study was to set the direction for the future of Jeongseon County's public libraries and provide appropriate strategies. To achieve this, an examination of the local situation and characteristics of Jeongseon County was conducted, followed by an analysis of the operational status of the public libraries. Additionally, a satisfaction survey and demand analysis were conducted among the residents of Jeongseon County regarding the libraries, to analyze directions for library improvements. Ultimately, taking into account the local characteristics, library status, and residents' needs, an optimized strategy for the region was presented. As a result of the study, the operational goal to achieve the vision was set as "a life-friendly library that shares the healthy lives of residents of Jeongseon-gun," and emphasized its role as a companion close to daily life for the healthy lives of Jeongseon-gun residents. The four strategic tasks to promote the operational goals were expressed as "a library that grows with local residents," "a library that provides multicultural exchange," "a sustainable future-oriented library," and "a library that cooperates with the local community."