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The Settlement of Conflict in International Space Activities (우주활동에 있어서 분쟁의 해결과 예방)

  • Lee, Young-Jin
    • The Korean Journal of Air & Space Law and Policy
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    • v.25 no.1
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    • pp.159-203
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    • 2010
  • Together with the development of space science outer space law has become one of the most rapidly developing branches of international law. This reflects a general realization that these new activities must be subject to reasonable legal regulation if they are to serve the peaceful purposes of mankind without undue confusion and disorder. The exploration and use of outer space introduces many novel opportunities and dilemmas, and inspired insights are needed in the development of this new resource. In particular, the settlement of space law disputes is a relatively new discussion in international law. However, the significance of the settlement of space law disputes was acknowledged in various colloquia organized by legal academicians and practitioners around the world. Analysis of the dispute settlement provisions in space agreements plainly reveals the degree to which States persist to be mistrustful of any impingement to their sovereignty. They are reluctant to submit disputes to adjudication and binding arbitration, particularly when these provisions are negotiated between States which have dissimilar political, economic and social interests and demography. However, there is a slow but clear shift in this attitude as States realize the contemporary political, economic and technical pressures necessitating the lifting of the veil of State sovereignty. The development of an effective mechanism for the settlement of disputes arising in relation to the development of the exploration and exploitation of outer space has been the subject of global study by highly qualified publicists and international institutions. The 1972 Liability Convention is the space treaty with the most elaborate provisions for dispute settlement. However, it fails to ensure binding decisions. In this point, the 1998 Taipei Final Draft Convention may be a useful instrument for further consideration on whether an independent sectorialized dispute settlement mechanism should be established. Considering these circumstances it seemed essential to take legislative action to implement a system as comprehensive as the relevant legal framework are in the Law of the Sea and International Criminal Law mechanisms for dispute settlement and conflict avoidance from outer space activities.

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A Study on the Determination of Tramp Freight Rates (부정기선 운임율의 결정에 관한 이론적 고찰)

  • 이종인
    • Journal of the Korean Institute of Navigation
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    • v.4 no.2
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    • pp.45-79
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    • 1980
  • The aim of this paper is to analyze the mechanics of price formation in the tramp shipping. For the purpose of this study, the main characteristics of tramp freight rates and the market is examined, and a brief examination of the nature ofthe costs of operation is given which are essential for the understanding of the functioning of shipping firms as well as for the understanding of developments in the tramp freight market. The demand and supply relationships in the market is also analysed in detail. Tramp shipping is an industry that has a market which functions under conditions that are not dissimilar to the theoretical model of perfect competition. However, it does notmean that tramp shipping market is a perfectly competitive market. It is apparent that this realworld competitive system has its imperfections, which means that the market for tramp shipping is near to being a perfectly competitive market on an internaitonal scale and it is freight are therefore subjext to the laws of supply and demand. In theory, the minimum freight rate in the short term is that at which the lowest cost vessels will lay-up in preference to operating, and is equal to the variable costs minus lay-up costs; and this would imply that in all times except those of full employment for ships there is a tendency for newer low-cost, and, probably, faster vessels to be driving the older high-cost vessels in the breaker's yards. In this case, shipowners may be reluctant to lay-up their ships becasue of obligations to crews, or because they would lose credibility with shippers or financiers, or simply because of lost prestige. Mainly, however, the decision is made on strictly economic grounds. When, for example, the total operating costs minus the likely freight earnings are greater than the cost of taking the ship out of service, maintaining it, and recommissioning it, then a ship may be considered for laying-up; shipowners will, in other words, run the ships at freight earnings below operating costs by as much as the cost of laying them up. As described above, the freight rates fixed on the tramp shipping market are subject to the laws of supply and demand. In other words, the basic properties of supply and demand are of significance so far as price or rate fluctuations in the tramp freight market are concerned. In connection with the same of the demand for tramp shipping services, the following points should be brone in mind: (a) That the magnitude of demand for sea transport of dry cargoes in general and for tramp shipping services in particular is increasing in the long run. (b) That owning to external factors, the demand for tramp shipping services is capable of varying sharphy at a given going of time. (c) The demad for the industry's services tends to be price inelastic in the short run. On the other hand the demand for the services offered by the individual shipping firm tends as a rule to be infinitely price elastic. In the meantime, the properties of the supply of the tramp shipping facilities are that it cannot expand or contract in the short run. Also, that in the long run there is a time-lag between entrepreneurs' decision to expand their fleets and the actual time of delivery of the new vessels. Thus, supply is inelastic and not capable of responding to demand and price changes at a given period of time. In conclusion, it can be safely stated that short-run changes in freight rates are a direct result of variations in the magnitude of demand for tramp shipping facilities, whilest the average level of freight rates is brought down to relatively low levels over prolonged periods of time.

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The Effect of Aging Treatment on the High Temperature Fatigue Fracture Behavior of Friction Welded Domestic Heat Resisting Steels (SUH3-SUS 303) (마찰용접된 국산내열 강 (SUH3-SUS303 )의 시효열처리가 고온피로강도 및 파괴거동에 미치는 영향에 관한 연구)

  • Lee, Kyu-Yong;Oh, Sae-Kyoo
    • Journal of the Korean Society of Fisheries and Ocean Technology
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    • v.17 no.2
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    • pp.93-103
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    • 1981
  • It is well-known that nowadays heat resisting and anti-corrosive materials have been widely used as the components materials of gas turbines, nuclear power plants and engines etc. In the fields of machine production industry. And materials for engine components, like as the exhaust valve of internal combustion engine, have been required to operate under the high temperature range of $700^{\circ}C$-$800^{\circ}C$ and high pressured gas with repeated mechanical load for the high performance of engines. For these components, friction welding for bonding of dissimilar steels can be applied for in order to obtain process shortening, production cost reduction and excellent bonding quality. And age hardening recently has been noticed to the heat resisting materials for further strengthening of high temperature strength, especially high temperature fatigue strength. However, it is difficult to find out any report concerning the effects of age hardening for strengthening high temperature fatigue strength to the Friction welded heat resisting and anti-corrosive materials. In this study the experiment was carried out as the high temperature rotary bending fatigue testing under the condition of $700^{\circ}C$ high temperature to the friction welded domestic heat resisting steels, SUH3-SUS303, which were 10hr., 100hr. aging heat treated at $700^{\circ}C$ after solution treatment 1hr. at $1, 060^{\circ}C$ for the purpose of observing the effects of the high temperature fatigue strength and fatigue fracture behaviors as well as with various mechanical properties of welded joints. The results obtained are summarized as follows: 1) Through mechanical tests and micro-structural examinations, the determined optimum welding conditions, rotating speed 2420 rpm, heating pressure 8kg/mm super(2), upsetting pressure 22kg/mm super(2), the amount of total upset 7mm (heating time 3 sec and upsetting time 2 sec) were satisfied. 2) The solution treated material SUH 3, SUS 303, have the highest inclination gradient on S-N curve due to the high temperature fatigue testing for long time at $700^{\circ}C$. 3) The optimum aging time of friction welded SUH3-SUS 303, has been recognized near the 10hr. at $700^{\circ}C$ after the solution treatment of 1hr. at $1, 060^{\circ}C$. 4) The high temperature fatigue limits of aging treated materials were compared with those of raw material according to the extender of aging time, on 10hr. aging, fatigue limits were increased by SUH 3 75.4%, SUS 303 28.5%, friction welded joints SUH 3-SUS 303 44.2% and 100hr. aging the rates were 64.9%, 30.4% and 36.6% respectively. 5) The fatigue fractures occurred at the side of the base matal SUS303 of the friction welded joints SUH 3-SUS 303 and it is difficult to find out fractures at the friction welding interfaces. 6) The cracking mode of SUS 303, SUH 3-303 is intergranular in any case, but SUH 3 is fractured by transgranular cracking.

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A Study on the Sanctuary of the Residence in East China Sea Skirts Area (동중국해권 민가의 성역(聖域)에 관한 연구)

  • Youn, Lily;Onomichi, Kenji
    • Korean Journal of Heritage: History & Science
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    • v.43 no.2
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    • pp.60-81
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    • 2010
  • Jeju Island, in Korea, shows many characteristics that are differentiated from the rest of Korea. Its culture is rooted in mythology which advocates a egalitarian, rather than hierarchical, social structure, the place of women in the home is relatively high, and the formation of buildings, the separation of cooking and heating facilities, and the living format of residential homes is dissimilar. These disparities in culture indicate that Jeju Island's heritage was not formed only from influences from the North, but also from other places as well. To fill in the blanks, residential homes in Jeju Island were compared with those scattered throughout the East China Sea, which connect the southern coastline of the Korean peninsula and Jeju Island. The regions encompassed by the East China Sea, sharing the Kuroshio current and a seasonal wind, can be considered as one cultural region integrating cultural aspects from the continental North and the oceanbound South. The unique characteristics of southern culture as seen in southern residences was examined through an investigation of the sacred places in which gods were considered to dwell. First, the myths of these areas usually concerned with the ocean, and a sterile environment made sustenance impossible without a dual livelihood, usually taking on the forms of half-farming and half-fishing, or half-farming, half-gardening. Although family compositions were strongly matricentric or collateral thanks to southern influence, a patriarchical system like those found in the North were present in the upper classes and in the cities. Therefore, residential spaces were not divided based on age or gender, as in hierarchical societies, but according to family and function. Second, these areas had local belief systems based on animism and ancestor worship, and household deities were closely related to women, agriculture and fire. The deities of the kitchen, the granary and the toilet were mostly female, and the role of priest was often filled by a woman. After Buddhism and Confucianism were introduced from mainland Korea, China and Japan, the sacred areas of the household took on a dual form, integrating the female-focused local rites with male-centered Buddhist and Confucian rites. Third, in accordance with worship of a kitchen deity, a granary deity, and a toilet deity led to these areas of the home being separated into disparate buildings. Eventually, these areas became absorbed into the home as architectural technology was further developed and lifestyles were changed. There was also integration of northern and southern cultures, with rites concerning granary and toilet deities coming from China, and the personality of the kitchen deity being related to the southern sea. In addition, the use of stone in separate kitchens, granaries, and toilets is a distinguishing characteristic of the East China Sea. This research is a part of the results gained from a project funded by the Korea Research Foundation in 2006.

Dietary and health characteristics of the young-old and the old-old by food security status: analysis of data from the 6th (2013 ~ 2015) Korea National Health and Nutrition Examination Survey (전기노인과 후기노인의 식품안정성에 따른 식생활 및 건강 특성 : 제6기 (2013~2015년) 국민건강영양조사 자료 분석)

  • Bae, Ajung;Yoon, Jihyun;Yun, Soh-Yoon;Asano, Kana
    • Journal of Nutrition and Health
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    • v.52 no.1
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    • pp.104-117
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    • 2019
  • Purpose: This study examined dietary and health characteristics of the young-old and the old-old by food security status. Methods: The study used data from the $6^{th}$ (2013 ~ 2015) Korea National Health and Nutrition Examination Survey. The study subjects consisted of 3,948 subjects, of whom 2,445 were the young-old (aged 65 to 74 years) and 1,503 were the old-old (aged 75 years and over). Food security status was evaluated using an 18-item questionnaire. Energy intake, nutrient densities, and prevalence of insufficient nutrient intake were assessed. Food intake was evaluated in terms of the number of food group servings. Dietary behaviors and health status were also assessed. Results: The prevalence of food insecurity among the young-old and the old-old was 10.0% and 11.6%, respectively. Among the young-old, the food insecure group had a significantly higher level of prevalence of insufficient intake for all the nutrients (protein, vitamin A, thiamin, riboflavin, niacin, vitamin C, calcium, phosphorous, and iron) assessed in this study compared with the food secure group. In case of the old-old, significant differences were found only for four nutrients (protein, riboflavin, niacin, and phosphorus) in the prevalence of insufficient nutrient intake between the food secure and the food insecure groups. Kinds of food groups with significantly different numbers of servings by food security status were dissimilar between the two age groups. In both the age groups, the food insecure group consumed a significantly lower number of servings in meat fish eggs legumes and fruits than the food secure group; grains and vegetables intake in the young-old and oils sweets intake in the old-old differed in the number of servings by food security status. Among the young-old, the prevalence of chewing difficulties in the food insecure group was significantly higher than that of the food secure group, while among the old-old, no significant differences were found by food security status. Conclusion: Dietary and health characteristics of the young-old and the old-old differed by food security status. Such differences were more apparent in the young-old than the old-old. Therefore, it is suggested that food and nutrition assistant programs should be designed with consideration of the differences.

Application of diversity of recommender system accordingtouserpreferencechange (사용자 선호도 변화에 따른 추천시스템의 다양성 적용)

  • Na, Hyeyeon;Nam, Kihwan
    • Journal of Intelligence and Information Systems
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    • v.26 no.4
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    • pp.67-86
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    • 2020
  • Recommender Systems have been huge influence users and business more and more. Recently the importance of E-commerce has been reached rapid growth greatly in world-wide COVID-19 pandemic. Recommender system is the center of E-commerce lively. Top ranked E-commerce managers mentioned that recommender systems have a major influence on customer's purchase such as about 50% of Netflix, Amazon sales from their recommender systems. Most algorithms have been focused on improving accuracy of recommender system regardless of novelty, diversity, serendipity etc. Recommender systems with only high accuracy cannot satisfy business long-term profit because of generating sales polarization. In addition, customers do not experience enjoyment of shopping from only focusing accuracy recommender system because customer's preference is changed constantly. Therefore, recommender systems with various values need to be developed for user's high satisfaction. Reranking is the most useful methodology to realize diversity of recommender system. In this paper, diversity of recommender system is represented through constructing high similarity with users who have different preference using each user's purchased item's category algorithm. It is distinguished from past research approach which is changing the algorithm of recommender system without user's diversity preference level. We tried to discover user's diversity preference level and observed the results how the effect was different according to user's diversity preference level. In addition, graph-based recommender system was used to show diversity through user's network, not collaborative filtering. In this paper, Amazon Grocery and Gourmet Food data was used because the low-involvement product, such as habitual product, foods, low-priced goods etc., had high probability to show customer's diversity. First, a bipartite graph with users and items simultaneously is constructed to make graph-based recommender system. However, each users and items unipartite graph also need to be established to show diversity of recommender system. The weight of each unipartite graph has played crucial role changing Jaccard Distance of item's category. We can observe two important results from the user's unipartite network. First, the user's diversity preference level is observed from the network and second, dissimilar users can be discovered in the user's network. Through the research process, diversity of recommender system is presented highly with small accuracy loss and optimalization for higher accuracy is possible controlling diversity ratio. This paper has three important theoretical points. First, this research expands recommender system research for user's satisfaction with various values. Second, the graph-based recommender system is developed newly. Third, the evaluation indicator of diversity is made for diversity. In addition, recommender systems are useful for corporate profit practically and this paper has contribution on business closely. Above all, business long-term profit can be improved using recommender system with diversity and the recommender system can provide right service according to user's diversity level. Lastly, the corporate selling low-involvement products have great effect based on the results.

The effect of the decision to use innovative services on the choice of consumers with a risk-averse tendency (혁신 서비스 이용 결정이 위험회피 성향 소비자의 선택에 미치는 영향)

  • Park, Kikyoung
    • Journal of Service Research and Studies
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    • v.13 no.2
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    • pp.146-160
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    • 2023
  • The spread of non-face-to-face services due to the COVID-19 pandemic has brought many changes in consumers' purchasing behavior and attracted much attention to new services. Could trying new services caused by this sudden environmental change alter consumers's choice patterns? This study proposes the research question of whether these new service experiences can change consumers' existing choice behavior, especially for risk-averse consumers who maintain their existing choice behavior or prefer safe alternatives. In this study, we examined whether trying out an unmanned payment services, one of innovative services that emerged after the pandemic crisis, can change the existing choice behavior of risk-averse consumers, i.e., make them more likely to prefer risky alternatives to safe alternatives. To accomplish these research goals, this research conducted one pilot survey and one study. The results of pilot survey showed that the stronger the prevention-focus tendency, the lower the self-efficacy to use the innovative service, with a negative relationship between them. Based on these findings, the study used an experimental method to examine the interaction effects between the use of innovation services and consumers' regulatory focus in a choice behavior and to explore the psychological mechanisms behind them. According to the results, it is found that prevention-focused consumers were more likely to choose risky alternatives and dissimilar extended brands following a trial of an unmanned payment service compared to not using that service. In contrast, promotion-focused consumers did not show different choice patterns regardless of following a trial of an innovative service. Furthermore, these results for prevention-focused consumers confirm the role of self-efficacy as a psychological mechanism. These findings shed light on the role of self-efficacy which has discussed in positive psychology into marketing area. Moreover, practical and academic implications are suggested by the finding that behavioral change occurs in risk-averse consumers, who are known to be hesitant to try new behaviors, indicating market expansion related to potential consumers for the use of the innovation services.

The Influence Evaluation of $^{201}Tl$ Myocardial Perfusion SPECT Image According to the Elapsed Time Difference after the Whole Body Bone Scan (전신 뼈 스캔 후 경과 시간 차이에 따른 $^{201}Tl$ 심근관류 SPECT 영상의 영향 평가)

  • Kim, Dong-Seok;Yoo, Hee-Jae;Ryu, Jae-Kwang;Yoo, Jae-Sook
    • The Korean Journal of Nuclear Medicine Technology
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    • v.14 no.1
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    • pp.67-72
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    • 2010
  • Purpose: In Asan Medical Center we perform myocardial perfusion SPECT to evaluate cardiac event risk level for non-cardiac surgery patients. In case of patients with cancer, we check tumor metastasis using whole body bone scan and whole body PET scan and then perform myocardial perfusion SPECT to reduce unnecessary exam. In case of short term in patients, we perform $^{201}Tl$ myocardial perfusion SPECT after whole body bone scan a minimum 16 hours in order to reduce hospitalization period but it is still the actual condition in which the evaluation about the affect of the crosstalk contamination due to the each other dissimilar isotope administration doesn't properly realize. So in our experiments, we try to evaluate crosstalk contamination influence on $^{201}Tl$ myocardial perfusion SPECT using anthropomorphic torso phantom and patient's data. Materials and Methods: From 2009 August to September, we analyzed 87 patients with $^{201}Tl$ myocardial perfusion SPECT. According to $^{201}Tl$ myocardial perfusion SPECT yesterday whole body bone scan possibility of carrying out, a patient was classified. The image data are obtained by using the dual energy window in $^{201}Tl$ myocardial perfusion SPECT. We analyzed $^{201}Tl$ and $^{99m}Tc$ counts ratio in each patients groups obtained image data. We utilized anthropomorphic torso phantom in our experiment and administrated $^{201}Tl$ 14.8 MBq (0.4 mCi) at myocardium and $^{99m}Tc$ 44.4 MBq (1.2 mCi) at extracardiac region. We obtained image by $^{201}Tl$ myocardial perfusion SPECT without gate method application and analyzed spatial resolution using Xeleris ver 2.0551. Results: In case of $^{201}Tl$ window and the counts rate comparison result yesterday whole body bone scan of being counted in $^{99m}Tc$ window, the difference in which a rate to 24 hours exponential-functionally notes in 1:0.114 with Ventri (GE Healthcare, Wisconsin, USA), 1:0.249 after the bone tracer injection in 12 hours in 1:0.411 with 1:0.79 with Infinia (GE healthcare, Wisconsin, USA) according to a reduction a time-out was shown (Ventri p=0.001, Infinia p=0.001). Moreover, the rate of the case in which it doesn't perform the whole body bone scan showed up as the average 1:$0.067{\pm}0.6$ of Ventri, and 1:$0.063{\pm}0.7$ of Infinia. According to the phantom after experiment spatial resolution measurement result, and an addition or no and time-out of $^{99m}Tc$ administrated, it doesn't note any change of FWHM (p=0.134). Conclusion: Through the experiments using anthropomorphic torso phantom and patients data, we found that $^{201}Tl$ myocardium perfusion SPECT image later carried out after the bone tracer injection with 16 hours this confirmed that it doesn't receive notable influence in spatial resolution by $^{99m}Tc$. But this investigation is only aimed to image quality, so it needs more investigation in patient's radiation dose and exam accuracy and precision. The exact guideline presentation about the exam interval should be made of the validation test which is exact and in which it is standardized about the affect of the crosstalk contamination according to the isotope use in which it is different later on.

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The Research on Recommender for New Customers Using Collaborative Filtering and Social Network Analysis (협력필터링과 사회연결망을 이용한 신규고객 추천방법에 대한 연구)

  • Shin, Chang-Hoon;Lee, Ji-Won;Yang, Han-Na;Choi, Il Young
    • Journal of Intelligence and Information Systems
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    • v.18 no.4
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    • pp.19-42
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    • 2012
  • Consumer consumption patterns are shifting rapidly as buyers migrate from offline markets to e-commerce routes, such as shopping channels on TV and internet shopping malls. In the offline markets consumers go shopping, see the shopping items, and choose from them. Recently consumers tend towards buying at shopping sites free from time and place. However, as e-commerce markets continue to expand, customers are complaining that it is becoming a bigger hassle to shop online. In the online shopping, shoppers have very limited information on the products. The delivered products can be different from what they have wanted. This case results to purchase cancellation. Because these things happen frequently, they are likely to refer to the consumer reviews and companies should be concerned about consumer's voice. E-commerce is a very important marketing tool for suppliers. It can recommend products to customers and connect them directly with suppliers with just a click of a button. The recommender system is being studied in various ways. Some of the more prominent ones include recommendation based on best-seller and demographics, contents filtering, and collaborative filtering. However, these systems all share two weaknesses : they cannot recommend products to consumers on a personal level, and they cannot recommend products to new consumers with no buying history. To fix these problems, we can use the information which has been collected from the questionnaires about their demographics and preference ratings. But, consumers feel these questionnaires are a burden and are unlikely to provide correct information. This study investigates combining collaborative filtering with the centrality of social network analysis. This centrality measure provides the information to infer the preference of new consumers from the shopping history of existing and previous ones. While the past researches had focused on the existing consumers with similar shopping patterns, this study tried to improve the accuracy of recommendation with all shopping information, which included not only similar shopping patterns but also dissimilar ones. Data used in this study, Movie Lens' data, was made by Group Lens research Project Team at University of Minnesota to recommend movies with a collaborative filtering technique. This data was built from the questionnaires of 943 respondents which gave the information on the preference ratings on 1,684 movies. Total data of 100,000 was organized by time, with initial data of 50,000 being existing customers and the latter 50,000 being new customers. The proposed recommender system consists of three systems : [+] group recommender system, [-] group recommender system, and integrated recommender system. [+] group recommender system looks at customers with similar buying patterns as 'neighbors', whereas [-] group recommender system looks at customers with opposite buying patterns as 'contraries'. Integrated recommender system uses both of the aforementioned recommender systems to recommend movies that both recommender systems pick. The study of three systems allows us to find the most suitable recommender system that will optimize accuracy and customer satisfaction. Our analysis showed that integrated recommender system is the best solution among the three systems studied, followed by [-] group recommended system and [+] group recommender system. This result conforms to the intuition that the accuracy of recommendation can be improved using all the relevant information. We provided contour maps and graphs to easily compare the accuracy of each recommender system. Although we saw improvement on accuracy with the integrated recommender system, we must remember that this research is based on static data with no live customers. In other words, consumers did not see the movies actually recommended from the system. Also, this recommendation system may not work well with products other than movies. Thus, it is important to note that recommendation systems need particular calibration for specific product/customer types.

Studies on nutrient sources, fermentation and harmful organisms of the synthetic compost affecting yield of Agaricus bisporus (Lange) Sing (양송이 수량(收量)에 미치는 합성퇴비배지(合成堆肥培地)의 영양원(營養源), 발효(醱酵) 및 유해생물(有害生物)에 관((關)한 연구(硏究))

  • Shin, Gwan-Chull
    • The Korean Journal of Mycology
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    • v.7 no.1
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    • pp.13-73
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    • 1979
  • These studies were conducted to investigate nutrient sources and supplementary materials of synthetic compost media for Agaricus bisporus culture. Investigation were carried out to establish the optimum composition for compost of Agaricus bisporus methods of out-door fermentation and peakheating with rice straw as the main substrate of the media. The incidence and flora of harmful organisms in rice straw compost and their control were also studied. 1. When rice straw was used as the main substrate in synthetic compost as a carbon source. yields were remarkably high. Fermentation was more rapid than that of barley straw or wheat straw, and the total nitrogen content was high in rice straw compost. 2. Since the morphological and physico-chemical nature of Japonica and Indica types of rice straw are greatly dissimilar. there were apparent differences in the process of compost fermentation. Fermentation of Indica type straw proceeded more rapidly with a shortening the compost period, reducing the water supply, and required adding of supplementary materials for producing stable physical conditions. 3. Use of barley straw compost resulted in a smaller crop compared with rice straw. but when a 50%, barley straw and 50% rice straw mixture was used, the yield was almost the same as that using only rice straw. 4. There were extremely high positive correlations between yield of Agaricus bisporus and the total nitrogen, organic nitrogen, amino acids, amides and amino sugar nitrogen content of compost. The mycerial growth and fruit body formation were severely inhibited by ammonium nitrogen. 5. When rice straw was used as the main substrate for compost media, urea was the most suitable source of nitrogen. Poor results were obtained with calcium cyanamide and ammonium sulfate. When urea was applied three separate times, nitrogen loss during composting was decreased and the total nitrogen content of compost was increased. 6. The supplementation of organic nutrient activated compost fermentation and increased yield of Agaricus bisporus. The best sources of organic nutrients were: perilla meal, sesame meal, wheat bran and poultry manure, etc. 7. Soybean meal, tobacco powder and glutamic acid fermentation by-products which were industrial wastes, could be substituted for perilla meal, sesame meal and wheat bran as organic nutrient sources for compost media. B. When gypsum and zeolite were added to rice straw. physical deterioration of compost due to excess moisture and caramelization was observed. The Indica type of straw was more remarkable in increase of yield of Agricus bisporus by addition of supplementing materials than Japonica straw. 9. For preparing rice straw compost, the best mixture was prepared by 10% poultry manure, 5% perilla meal, 1. 2 to 1. 5% urea and 1% gypsum. At spring cropping, it was good to add rice bran to accelerate heat generation of the compost heap. 10. There was significantly high positive correlation (r=0.97) between accumulated temperature and the decomposition degree of compost during outdoor composting. The yield was highest at accumulated temperatures between 900 and $1,000^{\circ}C$. 11. Prolonging the composting period brought about an increase in decomposition degree and total nitrogen content, but a decrease in ammonium nitrogen. In the spring the suitable period of composting was 20 to 25 days. and about 15 days in autumn. For those periods, the degree of decomposition was 19 to 24%. 12. Compactness of wet compost at filling caused an increase in the residual ammonium nitrogen. methane and organic acid during peak heating. There was negative correlation between methane content and yield (r=0.76)and the same was true between volatile organic acid and yield (r=0.73). 13. In compost with a moisture content range between 69 to 80% at filling. the higher the moisture content, the lower the yield (r=0.78). This result was attributed to a reduction in the porosity of compost at filling the beds. The optimum porosity for good fermentation was between 41 and 53%. 14. Peak heating of the compost was essential for the prevention of harmful microorganisms and insect pests. and for the removal of excess ammonia. It was necessary to continue fer mentatiion for four days after peak heating. 15. Ten species of fungi which are harmful or competitive to Agaricus bisporus were identified from the rice compost, including Diehliomyces microsporus, Trichoderma sp. and Stysanus stemoites. The frequency of occurrance was notably high with serious damage to Agaricus bisporus. 16. Diehliomyces microsporus could be controlled by temperature adjustment of the growing room and by fumigating the compost and the house with Basamid and Vapam. Trichoderma was prevented by the use of Bavistin and Benomyl. 17. Four species of nematodes and five species of mites occured in compost during out-door composting. These orgnanisms could be controlled through peakheating compost for 6 hours at $60^{\circ}C$.

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