• Journal of Intelligence and Information Systems
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• v.22 no.1
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• pp.159-185
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• 2016

Planning a multi-day trip is a complex, yet time-consuming task. It usually starts with selecting a list of points of interest (POIs) worth visiting and then arranging them into an itinerary, taking into consideration various constraints and preferences. When choosing POIs to visit, one might ask friends to suggest them, search for information on the Web, or seek advice from travel agents; however, those options have their limitations. First, the knowledge of friends is limited to the places they have visited. Second, the tourism information on the internet may be vast, but at the same time, might cause one to invest a lot of time reading and filtering the information. Lastly, travel agents might be biased towards providers of certain travel products when suggesting itineraries. In recent years, many researchers have tried to deal with the huge amount of tourism information available on the internet. They explored the wisdom of the crowd through overwhelming images shared by people on social media sites. Furthermore, trip planning problems are usually formulated as 'Tourist Trip Design Problems', and are solved using various search algorithms with heuristics. Various recommendation systems with various techniques have been set up to cope with the overwhelming tourism information available on the internet. Prediction models of recommendation systems are typically built using a large dataset. However, sometimes such a dataset is not always available. For other models, especially those that require input from people, human computation has emerged as a powerful and inexpensive approach. This study proposes CYTRIP (Crowdsource Your TRIP), a multi-day trip itinerary planning system that draws on the collective intelligence of contributors in recommending POIs. In order to enable the crowd to collaboratively recommend POIs to users, CYTRIP provides a shared workspace. In the shared workspace, the crowd can recommend as many POIs to as many requesters as they can, and they can also vote on the POIs recommended by other people when they find them interesting. In CYTRIP, anyone can make a contribution by recommending POIs to requesters based on requesters' specified preferences. CYTRIP takes input on the recommended POIs to build a multi-day trip itinerary taking into account the user's preferences, the various time constraints, and the locations. The input then becomes a multi-day trip planning problem that is formulated in Planning Domain Definition Language 3 (PDDL3). A sequence of actions formulated in a domain file is used to achieve the goals in the planning problem, which are the recommended POIs to be visited. The multi-day trip planning problem is a highly constrained problem. Sometimes, it is not feasible to visit all the recommended POIs with the limited resources available, such as the time the user can spend. In order to cope with an unachievable goal that can result in no solution for the other goals, CYTRIP selects a set of feasible POIs prior to the planning process. The planning problem is created for the selected POIs and fed into the planner. The solution returned by the planner is then parsed into a multi-day trip itinerary and displayed to the user on a map. The proposed system is implemented as a web-based application built using PHP on a CodeIgniter Web Framework. In order to evaluate the proposed system, an online experiment was conducted. From the online experiment, results show that with the help of the contributors, CYTRIP can plan and generate a multi-day trip itinerary that is tailored to the users' preferences and bound by their constraints, such as location or time constraints. The contributors also find that CYTRIP is a useful tool for collecting POIs from the crowd and planning a multi-day trip.

• Archives of design research
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• v.18 no.4 s.62
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• pp.105-118
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• 2005

Housing environment for human beings has been diversified and more convenient due to the development of high technology and civilization brought by industrialization in the 20th century. In the 21st century, how to overcome the ecological limit of biased development-centered advancement, that is, how to preserve and hand over a clean and healthy 'sustainable environment' to our next generations has been one of the most-talked about issues. Environmental symbiosis means a wider range of environmental harmony from micro-dimensional perspective to macro one. The three goals of a environmentally friendly house are to preserve global environment, to harmonize with the environment around, and to offer a healthy and comfortable living environment. From the point of view of environmental symbiosis, houses should be designed to save energy and natural resources for preservation of global environment, to collect such natural energy resources as solar heat and wind force, to recycle waste water, and recycle and reduce the amount of the waste matter. Now, the environmentally-friendly house became a new social mission that is difficult to not only challenge but also realize without conversion to a new paradigm, ecologism.

• Journal of the Korean earth science society
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• v.33 no.2
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• pp.126-138
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• 2012

Ultrasonic method is widely used for the evaluation of weathering index and of degree of deterioration because it is easily applicable $in$ $situ$. The basic idea of the method is that the ultrasonic velocity decreases as a rock is being weathered. Thus, the difference of ultrasonic velocities between fresh rock and weathered rock indicates the degree of weathering. In this method, the ultrasonic velocity of fresh rock is assumed to be 5,000 m/s. However, this assumption can cause significant errors in estimating weathering index, especially in case that those rocks of the same type have a wide range of ultrasonic velocities such as in Korea. Therefore, we obtained twenty rock specimens and sixty core samples commonly used for stone cultural heritages in Korea, and measured ultrasonic velocities. From the results, we found that the ultrasonic velocities of the same rock type, granite samples range from 3,118 to 5,380 m/s, and that the estimated weathering index can be highly biased if we use the fixed value of 5,000 m/s. We created a database (DB) by combining the measurement data and reported it. We also measured ultrasonic velocities by direct and indirect methods to quantify the calibration coefficient for each sampling site. We found that the calibration coefficients vary widely from site to site (1.31-1.76). Other factors, such as operator bias and temperature did not show any significant effect on errors in ultrasonic velocity measurements. Lastly, we applied our ultrasonic velocity DB and calibration coefficients to a stone cultural heritage, Bonghwang-ri Buddha statue. Our estimation of the weathering index was 0.3, 0.1 smaller than that by conventional method. The degree of deterioration was also different, "moderately weathered", while conventional method gave "highly weathered". Since other independent studies reported that the degree of deterioration of the Buddha statue was "moderately weathered", our estimation seems to be more accurate. Thus our method can help accurately evaluate the weathering index and the conservation planning for a stone cultural heritage.

• Journal of The Korean Association For Science Education
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• v.20 no.3
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• pp.396-410
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• 2000

In this study, the concept presentation form, the content coherence of sub-dimensional concepts and the number of concepts of the 6th and the 7th Korean curriculum were analyzed comparing the guide to developing the secondary biology curricula to develop biological literacy with BSCS. According to the result, the discrimination between concept levels in the frame of contents of the Korean curricula is insufficient, because each of concepts presented in the knowledge domain as upper level and sub-dimensional concept elements as lower level are simply arrayed. Considering too much concepts of ecosystem, genetics, reproduction and metabolism, there should be an effort to reform the biological curriculum to include concepts evenly, not in the biased state, to reflect all the 6 unifying principles by BSCS for developing students' biological literacy. Finally there should be an effort to reflect the characteristics of each subjects concretely among Science 10, Biology I and Biology IT in the 7th curriculum considering the result that essential concepts to develop biological literacy are presented more in some principles of Biology II than Biology I. Thinking the results of the present study, concrete discussions should be made to set up the standard reference about biological literacy and to present essential concepts for teaching and learning to develop it in the process of biology textbook development for meeting the 7th Korean curriculum and in the development of 8th Korean curriculum in advance.

• Journal of Intelligence and Information Systems
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• v.20 no.4
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• pp.107-120
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• 2014

This study proposes a novel recommender system using the structural hole analysis to reflect qualitative and emotional information in recommendation process. Although collaborative filtering (CF) is known as the most popular recommendation algorithm, it has some limitations including scalability and sparsity problems. The scalability problem arises when the volume of users and items become quite large. It means that CF cannot scale up due to large computation time for finding neighbors from the user-item matrix as the number of users and items increases in real-world e-commerce sites. Sparsity is a common problem of most recommender systems due to the fact that users generally evaluate only a small portion of the whole items. In addition, the cold-start problem is the special case of the sparsity problem when users or items newly added to the system with no ratings at all. When the user's preference evaluation data is sparse, two users or items are unlikely to have common ratings, and finally, CF will predict ratings using a very limited number of similar users. Moreover, it may produces biased recommendations because similarity weights may be estimated using only a small portion of rating data. In this study, we suggest a novel limitation of the conventional CF. The limitation is that CF does not consider qualitative and emotional information about users in the recommendation process because it only utilizes user's preference scores of the user-item matrix. To address this novel limitation, this study proposes cluster-indexing CF model with the structural hole analysis for recommendations. In general, the structural hole means a location which connects two separate actors without any redundant connections in the network. The actor who occupies the structural hole can easily access to non-redundant, various and fresh information. Therefore, the actor who occupies the structural hole may be a important person in the focal network and he or she may be the representative person in the focal subgroup in the network. Thus, his or her characteristics may represent the general characteristics of the users in the focal subgroup. In this sense, we can distinguish friends and strangers of the focal user utilizing the structural hole analysis. This study uses the structural hole analysis to select structural holes in subgroups as an initial seeds for a cluster analysis. First, we gather data about users' preference ratings for items and their social network information. For gathering research data, we develop a data collection system. Then, we perform structural hole analysis and find structural holes of social network. Next, we use these structural holes as cluster centroids for the clustering algorithm. Finally, this study makes recommendations using CF within user's cluster, and compare the recommendation performances of comparative models. For implementing experiments of the proposed model, we composite the experimental results from two experiments. The first experiment is the structural hole analysis. For the first one, this study employs a software package for the analysis of social network data - UCINET version 6. The second one is for performing modified clustering, and CF using the result of the cluster analysis. We develop an experimental system using VBA (Visual Basic for Application) of Microsoft Excel 2007 for the second one. This study designs to analyzing clustering based on a novel similarity measure - Pearson correlation between user preference rating vectors for the modified clustering experiment. In addition, this study uses 'all-but-one' approach for the CF experiment. In order to validate the effectiveness of our proposed model, we apply three comparative types of CF models to the same dataset. The experimental results show that the proposed model outperforms the other comparative models. In especial, the proposed model significantly performs better than two comparative modes with the cluster analysis from the statistical significance test. However, the difference between the proposed model and the naive model does not have statistical significance.

• Journal of Korea Technology Innovation Society
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• v.13 no.1
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• pp.68-98
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• 2010

This study was conducted to analyze the results of the implementation of next-generation growth engine program that was promoted across all government agencies for five years from 2004 as part of a range of initiatives aimed at expanding the nation's economic growth potential. The results were analyzed in this study using five indices: program purpose and design; strategic planning; program management; program results; and pan-governmental agency cooperation and coordination. The results of the study include the following. First, regarding program purpose and design, it was found that consistent leadership in the promotion of the programs was insufficient as the relevant program promotion systems and financial resources were dispersed among governmental agencies, even though the objectives and validity of the programs were recognized. Second, with regard to strategic planning, it was found that although the program objectives and technical development strategy had been established at the beginning of the program, they were biased toward the technical objectives and mainly implemented by the technology suppliers. Third, regarding program management, it was found that the responsibility for general administration, ranging from task planning to policy improvement, was given to the appointed program director but that the system of cooperation among the agencies was insufficient to carry out the relevant tasks. Fourth, regarding the results of the program, it was difficult to understand the results consistently as the economic objectives were not clearly presented, even though the technical objectives were achieved despite the short implementation period of the program. Fifth, with regard to pan-governmental agency cooperation and coordination, it was found that the coordination organization whose remit was to implement the program was established pursuant to the Basic Law on Science and Technology, but that no detailed regulations or guidelines on the operation of the organization were drawn up. To efficiently plan and execute future pan-governmental agency R&D programs that are similar to the next-generation new growth engine program, various requirements should be met, namely, 1) joint planning and consistent program design among governmental agencies, 2) clarification of the program objectives and budget allocation system, 3) establishment of a pan-governmental agency program operation and assessment system, 4) formulation of a strategy for linking R&D with standardization, and 5) enactment of pan-governmental agency joint operation rules.

• Clinical and Experimental Pediatrics
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• v.49 no.10
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• pp.1073-1078
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• 2006

Purpose : This study was performed to assess how a fetal diagnosis of congenital heart disease affects parents, as regards pregnancy management and care of infants after birth. Methods : Database search to find out abnormal fetal echocardiography performed at Seoul National University Children's Hospital from July 1988 to June 2003 revealed 370 examinations. After excluding both arrhythmias without structural cardiac disease and multiple pregnancies, 299 pregnancies remained and this data formed the basis of this analysis. We retrospectively reviewed the medical records with special attention to pregnancy outcomes and also tried to find out factors influencing parental decisions on whether to continue or terminate pregnancy. Results : In this study, the mean gestation age at diagnosis was $28{\pm}6.0weeks$. The mean age of mothers was $30{\pm}3.9$ years old. Younger gestational ages at diagnosis(P=0.000), more severe grades of fetal heart disease(P=0.002) and younger mothers(P=0.014) correlated with terminations of pregnanies. But the grades of fetal status, the grades of associated anomaly, whether in-vitro-fertilization was carried out or not and numbers of previous children were not significant. Conclusion : This study found that the earlier gestational ages at diagnosis, younger maternal age and higher grades of fetal heart disease tended to lead parent to select abortions. Fetal echocardiographies were performed too late. Moreover Koreans have a biased view that malformation is a something incurable and a tragedy not only to oneself, but also to a family. So parents select terminations of pregnancy, even in curable cases. This is very unethical.

• KDI Journal of Economic Policy
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• v.13 no.2
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• pp.97-127
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• 1991

This paper investigates the roles and the limitations of the Korean antitrust agencies-the Office of Fair Trade (OFT) and the Fair Trade Commission (FTC) during the making of the major industrial policies of the 1980's. The Korean antitrust agencies played only a minimal role in three major industrial policy-making issues in the 1980's- the enactment of the Industrial Development Act (IDA), the Industrial Rationalization Measures according to the IDA, and the Industrial Readjustment Measures on Consolidation of Large Insolvent Enterprises based on the revised Tax Exemption and Reduction Control Act. As causes for this performance bias in the Korean antitrust system, this paper considers five factors according to the current literature on implementation failure: ambiguous and insufficient statutory provisions of the Monopoly Regulation and Fair Trade Act (MRFTA); lack of resources; biased attitudes and motivations of the staff of the OFT and the FTC; bureaucratic incapability; and widespread misunderstanding about the roles and functions of the antitrust system in Korea. Among these five factors, bureaucratic incompetence and lack of understanding in various policy implementation environments about the roles and functions of the antitrust system have been regarded as the most important ones. Most staff members did not have enough educational training during their school years to engage in antitrust and fair trade policy-making. Furthermore, the high rate of staff turnover due to a mandatory personnel transfer system has prohibited the accumulation of knowledge and skills required for pursuing complicated structural antitrust enforcement. The limited capability of the OFT has put the agency in a disadvantaged position in negotiating with other economic ministries. The OFT has not provided plausible counter-arguments based on sound economic theories against other economic ministries' intensive market interventions in the name of rationalization and readjustment of industries. If the staff members of antitrust agencies have lacked substantive understanding of the antitrust and fair trade policy, the rest of government agencies must have had serious problems in understanding the correst roles and functions of the antitrust system. The policy environment of the Korean antitrust system, including other economic ministries, the Deputy Prime Minister, and President Chun, have tended to conceptualize the OFT more as an agency aiming only at fair trade policy and less as an agency that should enforce structural monopoly regulation as well. Based on this assessment of the performance of the Korean antitrust system, this paper evaluate current reform proposals for the MRFT A. The inclusion of the regulation of conglomerate mergers and of business divestiture orders may be a desirable revision, giving the MRFTA more complete provisions. However, given deficient staff experties and the unfavorable policy environments, it would be too optimistic and naive to expect that the inclusion of these provisions alone could improve the performance of the Korean antitrust system. In its conclusion, this paper suggests several policy recommendations for the Korean antitrust system, which would secure the stable development and accumulation of antitrust expertise for its staff members and enough understanding and conformity from its environments about its antitrust goals and functions.

• The Korean Journal of Financial Management
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• v.20 no.1
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• pp.93-124
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• 2003

This paper studies the financial analyst's forecasting activities on the firm's operating performance during the period from 1999 to 2003. In this study, financial analyst's forecasting activities are focused on the sales, operating income and net income and financial analyst's forecasting accuracy, forecasting revising patterns and forecasting activities to the unexpected firm's operating performance are studied. Some empirical findings in this study are as follows. First, standard estimate error on the sales, operating income and net income are all significantly negative value and so financial analyst's forecast on the firm's operating performance are upwardly biased. Second, domestic financial analyst's forecasting activities is relatively more accuracy than foreign financial analyst's forecasting activities. Third, forecasting time is more close to the end of the operating performance announcement day, forecasting activities are more accuracy. Fourth, comparing with individual financial analyst's forecast, consensus forecast is more accuracy. Fifth, in the comparative forecasting activities study according to the prior firm's operating performance, financial analyst's forecasting revision activities are found to be upward or downward. Sixth, financial analysts overreact in the sales forecast and underreact in the operating income and net income forecast. Seventh, in the empirical analysis on the Easterwood-Nutt's test model(1999) which the firm's performance change are divided into the expected performance change and the unexpected performance change, it is found that financial analyst's forecasting activities on the firm's operating performance are systematically optimistic.

• The Korean Journal of Nuclear Medicine Technology
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• v.17 no.2
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• pp.78-83
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• 2013

Purpose: SPECT/CT, a combination of SPECT and CT, is capable of expressing the results of attenuation correction on images biased by automatic program. As a result, this research evaluates the usefulness of images with CT attenuation correction, using various phantoms and images of patients. Materials and Methods: From July of 2012 to September of 2012, this research was conducted on the contrast, spatial resolution, and images of patients. We studied the contrast with IEC body phantom and Jaszczak phantom, while the spatial resolution was evaluated with NEMA triple line phantom. Further, a comparative study was carried out on the quality of the images, on the difference between the images before and after the CT attenuation correction. Results: Compared the differences between the contrast before and after the CT attenuation correction in IEC body phantom. The contrast was improved by 33.6% at minimum, 89.8% at maximum. In case of Jaszczak Phantom, the contrast was enhanced by 9.9% at minimum, 27.8% at maximum. In NEMA Triple line phantom, the resolution was raised by 4.5% in average: 4.4% in horizontal, 4.5% in vertical. In Anthropomorphic Torso Phantom, the perfusion score of the interior wall with the most severe attenuation was measured to be 29.4%. In the experiment carried out on myocardial perfusion SPECT/CT patients, 9% improvement was discovered in the interior wall, where the most dramatic attenuation occurred, after the CT attenuation correction. Conclusion: SPECT/CT proved its clinical usefulness by enabling the acquisition of images with enhanced contrast and spatial resolution compare to the ones resulted from SPECT.