• Title/Summary/Keyword: Rule Set

Search Result 729, Processing Time 0.029 seconds

An Implementation of Lighting Control System using Interpretation of Context Conflict based on Priority (우선순위 기반의 상황충돌 해석 조명제어시스템 구현)

  • Seo, Won-Il;Kwon, Sook-Youn;Lim, Jae-Hyun
    • Journal of Internet Computing and Services
    • /
    • v.17 no.1
    • /
    • pp.23-33
    • /
    • 2016
  • The current smart lighting is shaped to offer the lighting environment suitable for current context, after identifying user's action and location through a sensor. The sensor-based context awareness technology just considers a single user, and the studies to interpret many users' various context occurrences and conflicts lack. In existing studies, a fuzzy theory and algorithm including ReBa have been used as the methodology to solve context conflict. The fuzzy theory and algorithm including ReBa just avoid an opportunity of context conflict that may occur by providing services by each area, after the spaces where users are located are classified into many areas. Therefore, they actually cannot be regarded as customized service type that can offer personal preference-based context conflict. This paper proposes a priority-based LED lighting control system interpreting multiple context conflicts, which decides services, based on the granted priority according to context type, when service conflict is faced with, due to simultaneous occurrence of various contexts to many users. This study classifies the residential environment into such five areas as living room, 'bed room, study room, kitchen and bath room, and the contexts that may occur within each area are defined as 20 contexts such as exercising, doing makeup, reading, dining and entering, targeting several users. The proposed system defines various contexts of users using an ontology-based model and gives service of user oriented lighting environment through rule based on standard and context reasoning engine. To solve the issue of various context conflicts among users in the same space and at the same time point, the context in which user concentration is required is set in the highest priority. Also, visual comfort is offered as the best alternative priority in the case of the same priority. In this manner, they are utilized as the criteria for service selection upon conflict occurrence.

Study on Radioactive Material Management Plan and Environmental Analysis of Water (I) Study of Radioactive Substances in Water Management and Analysis to Eat of the US Environmental Protection Agency (Envirionmental Protection Agency) (물 환경의 방사성 물질 관리 방안과 분석법에 관한 연구 (I) 미국환경보호청(Envirionmental Protection Agency)의 먹는 물 방사성물질 관리와 분석법에 관한 고찰)

  • Her, Jae;Kim, Jung-Min;Min, Hye-Lim;Han, Seong-Gyu;Lim, Hyun-Jong;Jo, Han-Byeol;Noh, Young-Hoon;Lee, Ho-Sun;Park, Min-Suk
    • Journal of radiological science and technology
    • /
    • v.38 no.2
    • /
    • pp.163-170
    • /
    • 2015
  • The interest of the people in the radioactive contamination of the water has increased significantly and the study about analysis and management of radioactive materials are being actively conducted. And monitoring spots have been expanded to the range of public water as well as drinking water by publishing the rule of drinking water quality standards and examination in the Environmental Enforcement Ordinance No. 553 of Korea. In this study, US EPA was investigated as the foreign advanced cases and the way that is appropriate for the Korea was sought by analyzing investigate radionuclide, interval and management. As a result, in the selection part of investigate radionuclide, geological survey, status of nuclear power plants and the presence of the use of artificial radionuclides of the Korea should be investigated and additionally after the selection of a few radionuclides, the systems should be extended to cover all possible radionuclides by considering radioactive pollution levels in humans may be exposed due to the annual drinking water. In the part of the investigate interval, the concept(MCL, DL) should be set up for preventing concentration detection of above MCL and it needs to the maintenance and management. For example, when the concentration is more than MCL, it should be investigated on a quarterly and when the concentration is lower than MCL, it should be investigated to each different interval and management. And the US EPA divided the management area and make the roadmap for managing drinking water. The each classified area has been organized to match the state budget and labor force and the individual data have been managed effectively by HPGe, the NaI, TLD and so on.

The Effects of Hot Water Extraction of Wood Meal and the Addition of CaCl2 on Bending Strength and Swelling Ratio of Wood-Cement Board (목질(木質)의 열수추출(熱水抽出) 및 CaCl2 첨가(添加)가 목질(木質)-세멘트 보드의 휨강도(强度) 및 팽윤율(膨潤率)에 미치는 영향(影響))

  • Ahn, Won-Yung;Shin, Dong-So;Choi, Don-Ha
    • Journal of the Korean Wood Science and Technology
    • /
    • v.13 no.3
    • /
    • pp.49-53
    • /
    • 1985
  • The effects of pre-treatments, the hot water extraction of wood meal and the addition of chemical ($CaCl_2$) to wood-cement water system on the properties of wood-cement composite such as modulus of rupture (MOR), modulus of elasticity (MOE), water sorption ratio and swelling ratio of resulting boards were studied in this experiment. The wood meals through 0.83mm(20 mesh) and retained on 0.42mm(35 mesh) screen were prepared from Pinus densiflora S. at Z. and Larix leptolepsis G. For hot water extraction, 500 grams of wood meal for each species were heated to boiling with 1,500ml of distilled water in 2-liter beaker for 6 hours. Every 2 hours, the wood meals were washed with boiling distil1ed water and reheated to boiling again. After 6 hours boiling, the boiled wood particles were collected by pouring this particles on 200 mesh screen. The collected particles then washed twice with hot distilled water and dried for 24 hours in an oven at $109{\pm}20^{\circ}C$. A mixture of 663.4 grams of cement with 331.7 grams of wood meal based on oven-dry weight were dry-mixed in a plastic vessel. The mixture was kneaded with 497.6ml of distilled water in the ratio of 1.5ml of water to a gram of wood meal. To add calcium chloride to the mixture as an accelerator, $CaCl_2$ 4% solution by weight per volume, was added to pine-or larch-cement board in the ratio of 3% to cement weight. To set wood-cement board, this mixture was clamped at 30cm ${\times}$ 30cm, in thickness of 1.5cm for 3 days at room temperature, declamped and then placed at open condition for 17 days. The target density was 1.0. The four specimens sized to 5cm in width and 28cm in length were used for MOR and MOE test for each treatment. After MOR test, the tested specimens were cut to the size of 5cm ${\times}$ 5cm for water sorption and swelling test. The twenty specimens used to measure the water sorption ratio (soaking 24 hours) and ten of these were used for swelling ratio measurement The results obtained were as follows: 1) Larch was not suitable for wood-cement boards because larch-cement board developed no strength, but pine showed 97.9kg/$cm^2$ by hot water extraction. 2) To increase MOR, hot water extraction was more effective than the addition of $CaCl_2$ in pine and larch because the $CaCl_2$ addition was seemed to speed up the ratio of cement hydration without reacting with the wood substances. 3) The water sorption ratio was lowered by the addition of $CaCl_2$ to wood-cement system because the chemical additive accelerated the rate of cement hydration. 4) In pine-cement board, the swelling ratio from 0.37 to 0.42 percent was observed in length and the swelling ratio from 0.88 to 2.0 percent in thickness. As a rule, the swelling ratio of wood-cement board was very low and the swelling ratio in thickness was higher than in length.

  • PDF

Recommending Core and Connecting Keywords of Research Area Using Social Network and Data Mining Techniques (소셜 네트워크와 데이터 마이닝 기법을 활용한 학문 분야 중심 및 융합 키워드 추천 서비스)

  • Cho, In-Dong;Kim, Nam-Gyu
    • Journal of Intelligence and Information Systems
    • /
    • v.17 no.1
    • /
    • pp.127-138
    • /
    • 2011
  • The core service of most research portal sites is providing relevant research papers to various researchers that match their research interests. This kind of service may only be effective and easy to use when a user can provide correct and concrete information about a paper such as the title, authors, and keywords. However, unfortunately, most users of this service are not acquainted with concrete bibliographic information. It implies that most users inevitably experience repeated trial and error attempts of keyword-based search. Especially, retrieving a relevant research paper is more difficult when a user is novice in the research domain and does not know appropriate keywords. In this case, a user should perform iterative searches as follows : i) perform an initial search with an arbitrary keyword, ii) acquire related keywords from the retrieved papers, and iii) perform another search again with the acquired keywords. This usage pattern implies that the level of service quality and user satisfaction of a portal site are strongly affected by the level of keyword management and searching mechanism. To overcome this kind of inefficiency, some leading research portal sites adopt the association rule mining-based keyword recommendation service that is similar to the product recommendation of online shopping malls. However, keyword recommendation only based on association analysis has limitation that it can show only a simple and direct relationship between two keywords. In other words, the association analysis itself is unable to present the complex relationships among many keywords in some adjacent research areas. To overcome this limitation, we propose the hybrid approach for establishing association network among keywords used in research papers. The keyword association network can be established by the following phases : i) a set of keywords specified in a certain paper are regarded as co-purchased items, ii) perform association analysis for the keywords and extract frequent patterns of keywords that satisfy predefined thresholds of confidence, support, and lift, and iii) schematize the frequent keyword patterns as a network to show the core keywords of each research area and connecting keywords among two or more research areas. To estimate the practical application of our approach, we performed a simple experiment with 600 keywords. The keywords are extracted from 131 research papers published in five prominent Korean journals in 2009. In the experiment, we used the SAS Enterprise Miner for association analysis and the R software for social network analysis. As the final outcome, we presented a network diagram and a cluster dendrogram for the keyword association network. We summarized the results in Section 4 of this paper. The main contribution of our proposed approach can be found in the following aspects : i) the keyword network can provide an initial roadmap of a research area to researchers who are novice in the domain, ii) a researcher can grasp the distribution of many keywords neighboring to a certain keyword, and iii) researchers can get some idea for converging different research areas by observing connecting keywords in the keyword association network. Further studies should include the following. First, the current version of our approach does not implement a standard meta-dictionary. For practical use, homonyms, synonyms, and multilingual problems should be resolved with a standard meta-dictionary. Additionally, more clear guidelines for clustering research areas and defining core and connecting keywords should be provided. Finally, intensive experiments not only on Korean research papers but also on international papers should be performed in further studies.

History of the Korean Society of Applied Entomology for its First Fifty Years (한국응용곤충학회의 첫 50년 역사)

  • Boo, Kyung-Saeng
    • Korean journal of applied entomology
    • /
    • v.51 no.2
    • /
    • pp.171-190
    • /
    • 2012
  • The Korean Society of Applied Entomology (KSAE) celebrates its First 50 years history this year, 2011. It began in the year 1962, as the Korean Society of Plant Protection (KSPP) to discuss all aspects of plant protection including entomology and plant pathology. At that time it was one of the earliest scientific ones among agricultural societies in Korea. Before liberation from the Japanese colonial rule there were a few scientific societies for Japanese scientists only in the Korean Peninsula. It seemed that there was a single exception, in medical field, formed by and operated for Korean ethnics. Right after the liberation, Korean scientists rushed to form new scientific societies in the fields of mechanical engineering, architecture, textile, internal medicine, biology, etc. in 1945, mathematics, chemistry, metallurgy, etc. in 1946, and so on. But agricultural scientists had to wait for more time before setting up their own scientific society, Korean Agricultural Society(韓國農學會), comprising all agricultural subfields, in 1954. They had annual meetings and published their own journal every year until 1962. Then those working in the plant protection field established their own KSPP, right after their section meeting in 1962. At that time the total number of participants for KSPP were only around 50. KSPP scientists were interested in plant pathology, agricultural chemicals, weed science, or bioclimate, besides entomology. They had annual meetings once or twice a year until 1987 and published their own journal, Korean Journal of Plant Protection (KJPP), once a year at the earlier years but soon gradually increasing the frequency to four times a year later. Articles on entomology and plant pathology occupied about 40% each, but the number of oral or posters were a little bit higher on plant pathology than entomology, with the rest on nematology, agricultural chemicals, or soil microarthropods. There also had a number of symposia and special lectures. The presidentship lasted for two years and most of president served only one term, except for the first two. The current president should be $28^{th}$. In the year 1988, KSPP had to be transformed into the applied entomology society, Korean Society of Applied Entomology (KSAE), because most of plant pathologists participating left the society to set up their own one, Korean Society of Plant Pathology in 1984. Since that time the Society concentrates on entomology, basic and applied, with some notes on nematology, acarology, soil microarthropods, agricultural chemicals, etc. The Society has been hosting annual meetings at least twice a year with special lectures and symposia, from time to time, on various topics. It also hosted international symposia including binational scientific meetings twice with two different Japanese (applied entomology in 2003 and acarology in 2009) societies and the Asia-Pacific Congress of Entomology in 2005. The regular society meeting of this year, 2011, turns out to be the 43rd and this autumn non-regular meeting would be the 42nd. It has been publishing two different scientific journals, Korean Journal of Applied Entomology (KJAE) since 1988 and the Journal of Asia-Pacific Entomology (JAPE) since 1998. Both journals are published 4 times a year, with articles written in Korean or English in the first, but those in English only in the latter with cooperation from the Taiwan Entomological Society and the Malaysian Plant Protection Society since 2008. It is now enlisted as one of those SCI(science citation index) extended. The highest number of topics discussed at their annual meetings was on ecology, behavior, and host resistance. But at the annual meetings jointly with the Korean Society of Entomology, members were more interested in basic aspects, instead of applied aspects, such as physiology and molecular biology fields. Among those societies related to entomology and plant protection, plant pathology, pesticide, and applied entomology societies are almost similar in membership, but entomology and plant pathology societies are publishing more number of articles than any others. The Society is running beautifully, but there are a few points to be made for further improvement. First, the articles or posters should be correctly categorized on the journals or proceedings. It may be a good idea to ask members to give their own version of correct category for their submissions, either oral or poster or written publication. The category should be classified detailed as much as possible (one kind of example would be systematics, morphology, evolution, ecology, behavior, host preference or resistance, physiology, anatomy, chemical ecology, molecular biology, pathology, chemical control, insecticides, insecticide resistance, biocontrol, biorational control, natural enemies, agricultural pest, forest pest, medical pest, etc.) and such scheme should be given to members beforehand. The members should give one or two, first and second, choices when submitting, if they want. Then the categories might be combined or grouped during editing for optimal arrangement for journals or proceedings. Secondly the journals should carry complete content of the particular year and author index at the last issue of that year. I would also like to have other information, such as awards and awardees in handy way. I could not find any document for listing awards. Such information or article categorization may be assigned to one of the vice presidents. I would rather strongly recommend that the society should give more time and energy on archive management to keep better and more correct history records.

OD matrix estimation using link use proportion sample data as additional information (표본링크이용비를 추가정보로 이용한 OD 행렬 추정)

  • 백승걸;김현명;신동호
    • Journal of Korean Society of Transportation
    • /
    • v.20 no.4
    • /
    • pp.83-93
    • /
    • 2002
  • To improve the performance of estimation, the research that uses additional information addition to traffic count and target OD with additional survey cost have been studied. The purpose of this paper is to improve the performance of OD estimation by reducing the feasible solutions with cost-efficiently additional information addition to traffic counts and target OD. For this purpose, we Propose the OD estimation method with sample link use proportion as additional information. That is, we obtain the relationship between OD trip and link flow from sample link use proportion that is high reliable information with roadside survey, not from the traffic assignment of target OD. Therefore, this paper proposes OD estimation algorithm in which the conservation of link flow rule under the path-based non-equilibrium traffic assignment concept. Numerical result with test network shows that it is possible to improve the performance of OD estimation where the precision of additional data is low, since sample link use Proportion represented the information showing the relationship between OD trip and link flow. And this method shows the robust performance of estimation where traffic count or OD trip be changed, since this method did not largely affected by the error of target OD and the one of traffic count. In addition to, we also propose that we must set the level of data precision by considering the level of other information precision, because "precision problem between information" is generated when we use additional information like sample link use proportion etc. And we Propose that the method using traffic count as basic information must obtain the link flow to certain level in order to high the applicability of additional information. Finally, we propose that additional information on link have a optimal counting location problem. Expecially by Precision of information side it is possible that optimal survey location problem of sample link use proportion have a much impact on the performance of OD estimation rather than optimal counting location problem of link flow.

The Preventive Measures On Terrorism Against Overseas Korean Businessmen(A view of recent ethnic minority separation movement) (해외근무(海外覲務) 기업체(企業體)에 대(對)한 테러 방지책(防止策) - 최근(最近) 소수민족분리주의운동지역(小數民族分離主義運動地域)을 중심(中心)으로 -)

  • Choi, Yoon-Soo
    • Korean Security Journal
    • /
    • no.1
    • /
    • pp.351-370
    • /
    • 1997
  • This study concerns possible measures to prevent separatists' terrorist acts against overseas Korean businessmen. Of late, many Korean enterprises are helping a number of foreign countries develop their economy, by building factories and manning regional offices in those countries. But recent development of terrorism especially against Korean businessmen is alarming. This report discusses the need for Korean enterprises heading overseas to prepare themselves with awareness of terrorism and possible protective measures against it, besides their routine pursuance of profits; and for the government and prospective enterprises to refrain from investing in those countries having active separatist movements. If an investment has become inevitable, a careful survey of the region in conflict should be conducted and self-protective measures should be put in place through security information exchange, emergency coordination and training of personnel, etc. This study will first review the past terrorist incidents involving employees of overseas Korean enterprises, and then will focuss on seeking effective measures on the basis of the reported incidents. In carrying out the study, related literature from both home and abroad have been used along with the preliminary materials reported and known on the Internet from recent incidents. 1. The separatist movements of minority groups Lately, minority separatist groups are increasingly resorting to terrorism to draw international attention with the political aim of gaining extended self rule or independence. 2. The state of terrorism against overseas Korean enterprises and Koreans Korean enterprises are now operating businesses, and having their own personnel stationed, in 85 countries including those in South East Asia and Middle East regions. In Sri Lanka, where a Korean enterprise recently became a target of terrorist bombing, there are 75 business firms from Korea and some 700 Korean employees are stationed as of August 1996. A total of 19 different terrorist incidents have taken place against Koreans abroad since 1990. 3. Terrorism preventive measures Terrorism preventive measures are discussed in two ways: measures by the government and by the enterprises. ${\blacktriangleleft}$ Measures by the government - Possible measures at governmental level can include collection and dissemination of terrorist activity information. Emphasis should be given to the information on North Korean activities in particular. ${\blacktriangleleft}$ Measures by individual enterprises - Organizational security plan must be established by individual enterprises and there should also be an increase of security budget. A reason for reluctant effort toward positive security plan is the perception that the security budget is not immediately linked to an increment of profit gain. Ensuring safety for overseas personnel is a fundamental obligation of an enterprise. Consultation and information exchange on security plan, and an emergency support system at a threat to security must be sought after and implemented. 4. Conclusion Today's terrorism varies widely depending on reasons and causes, and its means has become increasingly informationalized and scientific as well while its method is becoming more clandestine and violent. Terrorist organizations are increasingly aiming at enterprises for acquisition of budgets needed for their activities. Korean enterprises have extended their business realm to foreign countries since 1970, exposing themselves to terrorism. Enterprises and their employees, therefore, should establish their own security measures on the one hand while the government must provide general measures, on the other, for the protection of the life and property of Korean residents abroad from terrorist attacks. In this regard, set-up of a counter terrorist organization that coordinates the efforts of government authorities in various levels in planning and executing counter terrorist measures is desired. Since 1965, when the hostile North Korea began to step up its terrorist activities against South Koreans, there have been 7 different occasions of assassination attempt on South Korean presidents and some 500 cases of various kidnappings and attempted kidnappings. North Korea, nervous over the continued economic growth and social stabilization of South Korea, is now concentrating its efforts in the destruction and deterioration of the national power of South Korea for its earlier realization of reunification by force. The possibility of North Korean terrorism can be divided into external terrorist acts and internal terrorist acts depending on the nationality of the terrorists it uses. The external terrorist acts include those committed directly by North Korean agents in South Korea and abroad and those committed by dissident Koreans, hired Korean residents, or international professionals or independent international terrorists bought or instigated by North Korea. To protect the life and property of Korean enterprises and their employees abroad from the threat of terrorism, the government's administrative support and the organizational efforts of enterprises should necessarily be directed toward the planning of proper security measures and training of employees. Also, proper actions should be taken against possible terrorist acts toward Korean business employees abroad as long as there are ongoing hostilities from minority groups against their governments.

  • PDF

A Study on the Efficiency of the North Korean Foreign Economy Arbitration Law (북한 대외경제중재법의 실효성 고찰)

  • Kim, Suk-Chul
    • Journal of Arbitration Studies
    • /
    • v.18 no.1
    • /
    • pp.167-184
    • /
    • 2008
  • The economic cooperation between the South and North Koreas is a very important issue for the unification and economic development of both Koreas. In order to reach a successful economic cooperation, there is a need to coordinate the differences of the two countries before unification. The economic cooperation and the cooperation in other sectors will be followed by the entire unification. It is necessary to prepare a mechanism that could peacefully solve the conflicts and disputes that could arise during the actual process of cooperation, which will secure stable investments and trades. The study on the possibility of introducing the arbitration system as a conflict solving mechanism between the two Koreas is a very important subject, and the basis of this study is on the examination of the arbitration laws of North Korea. Therefore, the study on the efficiency of the North Korean arbitration laws on foreign economy is studying the possibility of a systematical solution to economic conflicts between the South and North Koreas. The problems and possible solutions of the North Korean foreign economy arbitration laws are summarized as follows. First, juridical cooperation system for both South and North courts of justice needs to be set up to smoothly carry out the main procedures. Mutual correspondence and telecommunication needs to be guaranteed, also remittance and the movement of goods shall precede. Second, the free liquidation of businesses by unit and the individual and independent management of wealth of the North Korean economic bodies, organizations and businesses shall precede to independently liquidate wealth and thus make arbitration possible. Third, amendments in the North Korea's foreign economy arbitration law shall be made to some parts of regulations on arbitration agreements and specific contents of written arbitration agreements to avoid conflicts regarding arbitration agreement. Fourth, the members of the North Korean arbitration committee shall impartially manage the committee only without taking the role of arbitrator, and the clause that allows the North Korean committee to nominate the arbitrator shall be erased. In case an agreement regarding the number of arbitrators is not reached, the three arbitrators general rule shall be applied. In case of requests from any of the parties, a third country arbitrator nomination shall be guaranteed. Also, the requested arbitrator by the party shall be nominated with the cooperation of the court. Fifth, the trial in case of non-appearance or written trial shall be added to the North Korean law in to prevent intended negligence or evasion. Sixth, regulations regarding the court's investigation of evidence shall be added to the North Korean law to make fair arbitration possible in case that government power is needed in order to investigate evidence. Seventh, provisions regarding majority decision shall be added in the North Korean law in the impossibility of unanimous decisions, and the certified system in the arbitration committee official text shall be erased to prevent arrogation and assure the power of the decision made by the arbitration government. Eighth, as "the wrong decision approved" reason for cancellation of arbitration in the North Korean law includes the content of the decision made by the arbitrator could lead to uselessness of arbitration, amendment will be necessary to limit it to legitimacy of the arbitration agreement and wrong procedures. It is hoped that this thesis will be of important use in understanding the issues on the workability and the solutions to the South and North Koreas' arbitration that could be presented during the negotiations for the countries' economic cooperation.

  • PDF

Applying Meta-model Formalization of Part-Whole Relationship to UML: Experiment on Classification of Aggregation and Composition (UML의 부분-전체 관계에 대한 메타모델 형식화 이론의 적용: 집합연관 및 복합연관 판별 실험)

  • Kim, Taekyung
    • Journal of Intelligence and Information Systems
    • /
    • v.21 no.1
    • /
    • pp.99-118
    • /
    • 2015
  • Object-oriented programming languages have been widely selected for developing modern information systems. The use of concepts relating to object-oriented (OO, in short) programming has reduced efforts of reusing pre-existing codes, and the OO concepts have been proved to be a useful in interpreting system requirements. In line with this, we have witnessed that a modern conceptual modeling approach supports features of object-oriented programming. Unified Modeling Language or UML becomes one of de-facto standards for information system designers since the language provides a set of visual diagrams, comprehensive frameworks and flexible expressions. In a modeling process, UML users need to consider relationships between classes. Based on an explicit and clear representation of classes, the conceptual model from UML garners necessarily attributes and methods for guiding software engineers. Especially, identifying an association between a class of part and a class of whole is included in the standard grammar of UML. The representation of part-whole relationship is natural in a real world domain since many physical objects are perceived as part-whole relationship. In addition, even abstract concepts such as roles are easily identified by part-whole perception. It seems that a representation of part-whole in UML is reasonable and useful. However, it should be admitted that the use of UML is limited due to the lack of practical guidelines on how to identify a part-whole relationship and how to classify it into an aggregate- or a composite-association. Research efforts on developing the procedure knowledge is meaningful and timely in that misleading perception to part-whole relationship is hard to be filtered out in an initial conceptual modeling thus resulting in deterioration of system usability. The current method on identifying and classifying part-whole relationships is mainly counting on linguistic expression. This simple approach is rooted in the idea that a phrase of representing has-a constructs a par-whole perception between objects. If the relationship is strong, the association is classified as a composite association of part-whole relationship. In other cases, the relationship is an aggregate association. Admittedly, linguistic expressions contain clues for part-whole relationships; therefore, the approach is reasonable and cost-effective in general. Nevertheless, it does not cover concerns on accuracy and theoretical legitimacy. Research efforts on developing guidelines for part-whole identification and classification has not been accumulated sufficient achievements to solve this issue. The purpose of this study is to provide step-by-step guidelines for identifying and classifying part-whole relationships in the context of UML use. Based on the theoretical work on Meta-model Formalization, self-check forms that help conceptual modelers work on part-whole classes are developed. To evaluate the performance of suggested idea, an experiment approach was adopted. The findings show that UML users obtain better results with the guidelines based on Meta-model Formalization compared to a natural language classification scheme conventionally recommended by UML theorists. This study contributed to the stream of research effort about part-whole relationships by extending applicability of Meta-model Formalization. Compared to traditional approaches that target to establish criterion for evaluating a result of conceptual modeling, this study expands the scope to a process of modeling. Traditional theories on evaluation of part-whole relationship in the context of conceptual modeling aim to rule out incomplete or wrong representations. It is posed that qualification is still important; but, the lack of consideration on providing a practical alternative may reduce appropriateness of posterior inspection for modelers who want to reduce errors or misperceptions about part-whole identification and classification. The findings of this study can be further developed by introducing more comprehensive variables and real-world settings. In addition, it is highly recommended to replicate and extend the suggested idea of utilizing Meta-model formalization by creating different alternative forms of guidelines including plugins for integrated development environments.

Product Recommender Systems using Multi-Model Ensemble Techniques (다중모형조합기법을 이용한 상품추천시스템)

  • Lee, Yeonjeong;Kim, Kyoung-Jae
    • Journal of Intelligence and Information Systems
    • /
    • v.19 no.2
    • /
    • pp.39-54
    • /
    • 2013
  • Recent explosive increase of electronic commerce provides many advantageous purchase opportunities to customers. In this situation, customers who do not have enough knowledge about their purchases, may accept product recommendations. Product recommender systems automatically reflect user's preference and provide recommendation list to the users. Thus, product recommender system in online shopping store has been known as one of the most popular tools for one-to-one marketing. However, recommender systems which do not properly reflect user's preference cause user's disappointment and waste of time. In this study, we propose a novel recommender system which uses data mining and multi-model ensemble techniques to enhance the recommendation performance through reflecting the precise user's preference. The research data is collected from the real-world online shopping store, which deals products from famous art galleries and museums in Korea. The data initially contain 5759 transaction data, but finally remain 3167 transaction data after deletion of null data. In this study, we transform the categorical variables into dummy variables and exclude outlier data. The proposed model consists of two steps. The first step predicts customers who have high likelihood to purchase products in the online shopping store. In this step, we first use logistic regression, decision trees, and artificial neural networks to predict customers who have high likelihood to purchase products in each product group. We perform above data mining techniques using SAS E-Miner software. In this study, we partition datasets into two sets as modeling and validation sets for the logistic regression and decision trees. We also partition datasets into three sets as training, test, and validation sets for the artificial neural network model. The validation dataset is equal for the all experiments. Then we composite the results of each predictor using the multi-model ensemble techniques such as bagging and bumping. Bagging is the abbreviation of "Bootstrap Aggregation" and it composite outputs from several machine learning techniques for raising the performance and stability of prediction or classification. This technique is special form of the averaging method. Bumping is the abbreviation of "Bootstrap Umbrella of Model Parameter," and it only considers the model which has the lowest error value. The results show that bumping outperforms bagging and the other predictors except for "Poster" product group. For the "Poster" product group, artificial neural network model performs better than the other models. In the second step, we use the market basket analysis to extract association rules for co-purchased products. We can extract thirty one association rules according to values of Lift, Support, and Confidence measure. We set the minimum transaction frequency to support associations as 5%, maximum number of items in an association as 4, and minimum confidence for rule generation as 10%. This study also excludes the extracted association rules below 1 of lift value. We finally get fifteen association rules by excluding duplicate rules. Among the fifteen association rules, eleven rules contain association between products in "Office Supplies" product group, one rules include the association between "Office Supplies" and "Fashion" product groups, and other three rules contain association between "Office Supplies" and "Home Decoration" product groups. Finally, the proposed product recommender systems provides list of recommendations to the proper customers. We test the usability of the proposed system by using prototype and real-world transaction and profile data. For this end, we construct the prototype system by using the ASP, Java Script and Microsoft Access. In addition, we survey about user satisfaction for the recommended product list from the proposed system and the randomly selected product lists. The participants for the survey are 173 persons who use MSN Messenger, Daum Caf$\acute{e}$, and P2P services. We evaluate the user satisfaction using five-scale Likert measure. This study also performs "Paired Sample T-test" for the results of the survey. The results show that the proposed model outperforms the random selection model with 1% statistical significance level. It means that the users satisfied the recommended product list significantly. The results also show that the proposed system may be useful in real-world online shopping store.