• Journal of the HCI Society of Korea
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• v.1 no.1
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• pp.37-44
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• 2006

Specular reflections provide the visual feedback that describes the material type of an object, its local shape, and lighting environment. In photorealistic rendering, there have been a number of research available to render specular reflections effectively based on a local reflection model. In traditional cel animations and cartoons, specular reflections plays important role in representing artistic intentions for an object and its related environment reflections, so the shapes of highlights are quite stylistic. In this paper, we present a method to render and control stylized specular reflections using projective textures based on principal curvature analysis. Specifying a texture as a pattern of a highlight and projecting the texture on the specular region of a given 3D model, we can obtain a stylized representation of specular reflections. For a given polygonal model, a view point, and a light source, we first find the maximum specular intensity point, and then locate the texture projector along the line parallel to the normal vector and passing through the point. The orientation of the projector is determined by the principal directions at the point. Finally, the size of the projection frustum is determined by the principal curvatures corresponding to the principal directions. The proposed method can control the position, orientation, and size of the specular reflection efficiently by translating the projector along the principal directions, rotating the projector about the normal vector, and scaling the principal curvatures, respectively. The method is be applicable to real-time applications such as cartoon style 3D games. We implement the method by Microsoft DirectX 9.0c SDK and programmable vertex/pixel shaders on Nvidia GeForce FX 7800 graphics subsystems. According to our experimental results, we can render and control the stylized specular reflections for a 3D model of several ten thousands of triangles in real-time.

• Asian Pacific Journal of Cancer Prevention
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• v.16 no.1
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• pp.259-263
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• 2015

Background: In the field of cancer, the ICD-10 coding convention is based on the site of a neoplasm in the body and usually ignores the morphology, thus the same code may be assigned to tumors of different morphologic types in an organ. Nowadays, all general (provincial) and center hospitals in Thailand are equipped with the hospital information system (HIS) database. Objective: This study aimed to find the characteristics and magnitude of agreement represented by the positive predictive value (PPV) of provisional cancer diagnoses in the HIS database in Pattani Hospital in Thailand in comparison with the final cancer diagnosis of the ICD-10 codes generated from a well established cancer registry in Songklanagarind Hospital, the medical school hospital of Prince of Songkla University. Materials and Methods: Data on cancer patients residing in Pattani province who visited Pattani Hospital from January 2007 to May 2011 were obtained from the HIS database. The ICD-10 codes of the HIS computer database of Pattani Hospital were compared against the ICD-10 codes of the same person recorded in the hospital-based cancer registry of Songklanagarind Hospital. The degree of agreement or positive predictive value (PPV) was calculated for each sex and for both sexes combined. Results: A total of 313 cases (15.9%) could be matched in the two databases. Some 222 cases, 109 males and 113 females, fulfilled the criteria of referral from Pattani to Songklanagarind Hospitals. Of 109 male cancer cases, 76 had the same ICD-10 codes in both hospitals, thus, the PPV was 69.7% (95%CI: 60.2-78.2%). Agreement in 76 out of 113 females gave a PPV of 67.3% (95%CI: 57.8-75.8%). The two percentages were found non-significant with Fisher's exact p-value of 0.773. The PPV for combined cases of both sexes was 68.5% (95%CI: 61.9-74.5%). Conclusions: Changes in final diagnosis in the referral system are common, thus the summary statistics of a hospital without full investigation facilities must be used with care, as the statistics are biased towards simple diseases able to be investigated by available facilities. A systematic feedback of patient information from a tertiary to a referring hospital should be considered to increase the accuracy of statistics and to improve the comprehensive care of cancer patients.

• Journal of KIISE:Computer Systems and Theory
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• v.32 no.5
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• pp.219-231
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• 2005

Many applications in cluster computing require QoS (Quality of Service) services. Since performance predictability is essential to provide QoS service, underlying systems must provide predictable performance guarantees. One way to ensure such guarantees from network subsystems is to generate global schedules from applications'network requests and to execute the local portion of the schedules at each network interface. To ensure accurate execution of the schedules, it is essential that a global time base must be maintained by local clocks at each network interface. The task of providing a single time base is called a synchronization problem and this paper addresses the problem for system area networks. To solve the synchronization problem, FM-QoS (1) proposed a simple synchronization mechanism called FBS(Feedback-Based Synchronization) which uses built-in How control signals. This paper extends the basic notion of FM-QoS to a theoretical framework and generalizes it: 1) to identify a set of built-in network flow control signals for synchrony and to formalize it as a synchronizing schedule, and 2) to analyze the synchronization precision of FBS in terms of flow control parameters. Based on generalization, two application classes are studied for a single switch network and a multiple switch network. For each class, a synchroniring schedule is proposed and its bounded skew is analyzed. Unlike FM-QoS, the synchronizing schedule is proven to minimize the bounded skew value for a single switch network. To understand the analysis results in practical networks, skew values are obtained with flow control parameters of Myrinet-1280/SAN. We observed that the maximum bounded skew of FBS is 9.2 Usec or less over all our experiments. Based on this result, we came to a conclusion that FBS was a feasible synchronization mechanism in system area networks.

• Korean Chemical Engineering Research
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• v.61 no.4
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• pp.542-549
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• 2023

Since the growing interest in surrogate modeling, there has been continuous research aimed at simulating nonlinear chemical processes using data-driven machine learning. However, the opaque nature of machine learning models, which limits their interpretability, poses a challenge for their practical application in industry. Therefore, this study aims to analyze chemical processes using Explainable Artificial Intelligence (XAI), a concept that improves interpretability while ensuring model accuracy. While conventional sensitivity analysis of chemical processes has been limited to calculating and ranking the sensitivity indices of variables, we propose a methodology that utilizes XAI to not only perform global and local sensitivity analysis, but also examine the interactions among variables to gain physical insights from the data. For the ammonia synthesis process, which is the target process of the case study, we set the temperature of the preheater leading to the first reactor and the split ratio of the cold shot to the three reactors as process variables. By integrating Matlab and Aspen Plus, we obtained data on ammonia production and the maximum temperatures of the three reactors while systematically varying the process variables. We then trained tree-based models and performed sensitivity analysis using the SHAP technique, one of the XAI methods, on the most accurate model. The global sensitivity analysis showed that the preheater temperature had the greatest effect, and the local sensitivity analysis provided insights for defining the ranges of process variables to improve productivity and prevent overheating. By constructing alternative models for chemical processes and using XAI for sensitivity analysis, this work contributes to providing both quantitative and qualitative feedback for process optimization.

• Journal of Digital Convergence
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• v.6 no.3
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• pp.45-52
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• 2008

For the domestic digital contents, it is particularly important that the planning and mediating functions should cover the whole Industries so that dividends and assistance to reach all the way back to the primary contents-creating level, where economic risks are especially high. A proactive cooperation system or framework between the government, the businesses and research institutions, which would allow for free flow of interaction among these players, can play that role. We can broadly define cooperation frameworks into two; one between the central and the local governments and another among private-sector groups, such as companies, associations and groups. These players in the framework have differing, sometimes, conflicting views regarding the digital contents industry whether the digital contents should aim for skilled applicability or the abstract or whether the emphasis should rest on public interest or profitability. Immature competition and lack of trust among these players also give rise to such inefficiencies as overlap in investments, inexpertness and inefficient use of resources. We have proposed and realized the National Integrated Cooperation System to bridge these gaps among the major players in the industry. The National Integrated Cooperation System rests on the following major functions. The first major function of the NICS is to decipher any ambiguity that may be embedded in external Inputs by stratified role and bias. The second function is to create cooperative groups that will deal with the ambiguities based on its consequent situation. The third is a feedback function that will draw out a new cooperative way by re-feeding the capacities and the conflicts that stem from the existing organizations and strategies into cooperation and adjustment process. Our NICS has compared and evaluated with England and Australia digital content industry models under AHP(Analytic Hierarchy Process) method. NICS has turned out to be well designed and have strong points based on OECD innovation and cooperation criteria.

• Journal of the Korean Association of Geographic Information Studies
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• v.13 no.1
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• pp.35-49
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• 2010

KEPCO(Korean Electric Power Corporation) is now operating an incorporated system for designing and maintenance of electric power facilities called NDIS (New Distribution Information System). Given the structure of the nation which exclusively permits establishment of new electric facilities and maintenance, expertise (skilled knowledge) about the related system on the part of electric engineers is very important. But in the view of education and training, it is a reality that current offline ways of education based on application for educational courses at the KEPCO Academy, an education organization under KEPCO, are unsatisfactory in efficiency and availability to related engineers. Therefore, We realize that a simulation design education system which guarantees an easy access is required to make the best of the existing system NDIS. For this purpose the present work is a study on the development of a simulation education system to make local based NDIS real on the web, which enables related engineers to practice designing and get feedback of the result.

• The Journal of Korean Academic Society of Nursing Education
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• v.9 no.1
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• pp.155-162
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• 2003

The comparative study of the administration policy that the government and the local self-governing body have enforced to a handicapped child and the family, was made in South Korea and Japan. As data, I utilized brochures distributed to a handicapped child's guardian in the government publication, health center, and hospital of both countries and the homepage that each organization manages. With the investigation of (1) the handicapped child's present condition, population and entering-school situation, (2) the organization which can consult about a juvenile entering-school problem, (3) the public service with which the parents of handicapped child, or a handicapped child are provided and (4) the feedback surveys of (3)’s services, the followings were proved. In (1), the handicapped child's population and their school attendance are not be specified by the South Korea side. In (2), a private consultation organization is mainly opened and be hard to say that use is simple from the little of a kind. In (3), there is almost nothing than rehabilitation education as the administration policy, which is universally held for the handicapped child. Besides they cannot receive freely the education. In (4), it became clear not to carry out. The improvement from the direction of both hard and soft aspects - the institution of basic education for the handicapped child who lives in all areas and the equal opportunity to all children - is called for urgently.

• The Mathematical Education
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• v.56 no.2
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• pp.161-175
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• 2017

The purpose of this study is to compare and analyze the impact on low-achievers in mathematics who studied mathematics using Blended e-learning and Personalized system of instruction after school. Blended e-learning is defined as the management of e-learning using the e-study run by the education office in local. Personalized system of instruction was proceeded as follows; (1) all students are given a syllabicated learning task and a study guide, (2) students study the material autonomously according to their own pace for a certain period of time, (3) the teacher strengthens the students' motivation through grading and feedback after students study a subject and solve the evaluation problem. The learning materials for Personalized system of instruction are re-edited the offline education contents provided by the blended e-learning to the level of students. The 118 $7^{th}$ grade students from the D middle school participated in this study. The results were verified by achievement tests before and after the study, as well as survey regarding their attitude toward mathematics. The results are as follows. First, Blended e-learning has more positive impacts than Personalized system of instruction in mathematics achievement. Second, there was no difference in mathematics achievement according to their self-directed learning between Blended e-learning and Personalized system of instruction. Third, both types utilizing Blended e-learning and Personalized system of instruction have positive effect on attitude toward mathematics, and there is not their difference between two methods of teaching and learning mathematics.

• Journal of the Korean Society for Precision Engineering
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• v.28 no.1
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• pp.115-122
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• 2011

Recently, we have proposed a hypothesis that spinal structures have a stress sensor driving feedback mechanism, In the human spine, spinal structure could react to modify muscular action in such a way so as to equalize stress at the disc, therefore reduce the risk of injury, In this analysis, abdominal muscle and abdominal pressure, which were not included in the previous study, were added to identify those effects in spine stability during upright stance posture for the case where the intervertebral disc plays the role of mechanoreceptor, The musculoskeletal FE model was consisted with detailed whole lumbar spine, pelvis, sacrum, coccyx and simplified trunk model. Muscle architecture with 46 local muscles containing paraspinal muscle and 6 rectus abdominal muscles were assigned according to the acting directions. The magnitude of 4kPa was considered for abdominal pressure. Minimization of the nucleus pressure deviation and annulus fiber average tension stress deviation was chosen for cost function. Developed model provide nice coincidence with in-vivo measurement (nucleus pressure). Analysis was conducted according to existence of co-activation of abdominal muscle and abdominal pressure. Antagonistic activity of abdominal muscle produced stability of spinal column with relatively small amount of total muscle force. In contrast to the abdominal muscle, effect of abdominal pressure was not clear that was partly depending on the assumption of constant abdominal pressure.

• Journal of Korean Library and Information Science Society
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• v.21
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• pp.253-289
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• 1994

The purpose of this study is about the search pattern of LINNET (Library Information Network System) OPAC users by transaction log, maintained by POSTECH(Pohang University of Science and Technology) Central Library, to provide feedback information of OPAC system design. The results of this study are as follows. First, for the period of this analysis, there were totally 11, 218 log-ins, 40, 627 transaction logs and 3.62 retrievals per a log-in. Title keyword was the most frequently used, but accession number, bibliographic control number or call number was very infrequently used. Second, 47.02% of OPAC, searches resulted in zero retrievals. Bibliographic control number was the least successful search. User displayed 2.01% full information and 64.27% local information per full information. Third, special or advanced retrieval features are very infrequently used. Only 22.67% of the searches used right truncation and 0.71% used the qualifier. Only 1 boolean operator was used in every 22 retrievals. The most frequently used operator is 'and (&)' with title keywords. But 'bibliographical control number (N) and accessionnumber (R) are not used at all with any operators. The causes of search failure are as follows. 1. The item was not used in the database. (15, 764 times : 79.42%). 2. The wrong search key was used. (3, 761 times : 18.95%) 3. The senseless string (garbage) was entered. (324 times : 1.63%) On the basis of these results, some recommendations are suggested to improve the search success rate as follows. First, a n.0, ppropriate user education and online help function let users retrieve LINNET OPAC more efficiently. Second, several corrections of retrieval software will decrease the search failure rate. Third, system offers right truncation by default to every search term. This methods will increase success rate but should considered carefully. By a n.0, pplying this method, the number of hit can be overnumbered, and system overhead can be occurred. Fourth, system offers special boolean operator by default to every keyword retrieval when user enters more than two words at a time. Fifth, system assists searchers to overcome the wrong typing of selecting key by automatic korean/english mode change.