• Korean Journal of Clinical Pharmacy
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• v.19 no.1
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• pp.50-60
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• 2009

Highly variable drugs (within-subject variability greater than 30%) have been difficult to meet current regulatory acceptance criteria using a reasonable number of study subjects. In this study, we reviewed previous studies presenting alternative approaches for bioequivalence evaluation of highly variable drugs, and focused on an approach for widening the bioequivalence acceptance limits using within-subject variability. We discussed the suggested five solutions for highly variable drug including the deletion of $C_{max}$ of the bioequivalence criteria, direct expansion of bioequivalence limit, multiple dose studies in steady state, bioequivalence assessment on the metabolite, add-on study, and widening the bioequivalence acceptance limits based on reference variability. The methods for widening of bioequivalence limits based on reference variability are scaled average bioequivalence containing within-subject variability on reference drug (${\sigma}_{WR}$), population bioequivalence derived from total variability on reference drug (${\sigma}_{TR}$) and test drug (${\sigma}_{TT}$), and individual bioequivalence derived from subject by formulation interaction variability (${\sigma}_D$) and within subject variability on reference drug (${\sigma}_{WR}$) and test drug (${\sigma}_{TR}$). To apply these methods, the switching variability (${\sigma}_0$) will have to be set by the regulatory authorities. The proposals of bioequivalence evaluation approach for the highly variable in Korea are presented for both of new drug and reevaluation drug.

• Journal of Korean Society for Quality Management
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• v.50 no.1
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• pp.125-138
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• 2022

Purpose: Failure Mode and Effect Analysis (FMEA) is a widely utilized technique to measure product reliability by identifying potential failure modes. Even though FMEA techniques have been studied, the form of Risk Priority Number (RPN) used to evaluate risk priority in FMEA is still questionable because of its shortcomings. In this study, we suggest common RPN(cRPN) to resolve shortcomings of the traditional RPN and show the extensibility of cRPN. Methods: We suggest cRPN which is based on Cobb-Douglas production function, and represent the various application on weighting risk factors, weighted RPN in a mathematical way, and show the possibility of statistical approach. We also conduct numerical study to examine the difference of the traditional RPN and cRPN as well as the potential application from the analysis on marginal effects of each risk factor. Results: cRPN successfully integrates previously suggested approaches especially on the relative importance of risk factors and weighting RPN. Moreover, we analyze the effect of corrective actions in terms of econometric analysis using cRPN. Since cRPN is rely on the reliable mathematical model, there would be numerous applications using cRPN such as smart factory based on A.I. techniques. Conclusion: We propose a reliable mathematical model of RPN based on Cobb-Douglas production function. Our suggested model, cRPN, resolves various shortcomings such as consideration of the relative importance, the effect of combinations among risk factors. In addition, by adopting a reliable mathematical model, quantitative approaches are expected to be applied using cRPN. We find that cRPN can be utilized to the field of industry because it is able to be applied without modifying the entire systems or the conventional actions.

• International Journal of Fuzzy Logic and Intelligent Systems
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• v.12 no.2
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• pp.181-186
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• 2012

This paper proposes a method for evaluating web pages by considering implicit user reaction on web pages. Usually users spend more time and make more reactions, such as clicking, dragging and scrolling, while reading interesting pages. Based on this observation, a web page evaluation method by observing implicit user reaction is proposed. The system is designed with Ajax for observing user reactions, and neural networks for learning correlation between user reactions and usefulness of pages. The amounts of each type of user reactions are inputted to neural networks. Also the numbers of characters and images of pages are used as inputs because the amount of users' behaviors has a tendency to increase as the length of pages increase. The experiment is conducted with 113 people and 74 pages. Each page is ranked by users with a questionnaire. The proposed method shows more close ranking results to the user ranks than Google. That is, our system evaluates web pages more closely to users' viewpoint than Google. Although our experiment is limited, our result shows powerful potential of new element for web page evaluation. Some approaches evaluate web pages with their contents and some evaluate web pages with structural attributes, particularly links, of pages. Web page evaluation is for users, so the best evaluation can be done by users themselves. So, user feedback is one of the most important factors for web page evaluation. This paper proposes a new method which reflects user feedbacks on web pages.

• The Korean Journal of Pain
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• v.27 no.4
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• pp.353-359
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• 2014

Background: Epidural steroid injections are an accepted procedure for the conservative management of chronic backache caused by lumbar disc pathology. The purpose of this study was to evaluate the epidurographic findings for the midline, transforaminal and parasagittal approaches in lumbar epidural steroid injections, and correlating them with the clinical improvement. Methods: Sixty chronic lower back pain patients with unilateral radiculitis from a herniated/degenerated disc were enrolled. After screening the patients according to the exclusion criteria and randomly allocating them to 3 groups of 20 patients, fluoroscopic contrast enhanced epidural steroids were injected via midline (group 1), transforaminal (group 2) and parasagittal interlaminar (group 3) approaches at the level of the pathology. The fluoroscopic patterns of the three groups were studied and correlated with the clinical improvement measured by the VAS over the next 3 months; any incidences of complications were recorded. Results: The transforaminal group presented better results in terms of VAS reduction than the midline and parasagittal approach groups (P < 0.05). The epidurography showed a better ventral spread for both the transforaminal (P < 0.001) and the paramedian approaches (P < 0.05), as compared to the midline approach. The nerve root filling was greater in the transforaminal group (P < 0.001) than in the other two groups. The ventral spread of the contrast agent was associated with improvement in the VAS score and this difference was statistically significant in group 1 (P < 0.05), and highly significant in groups 2 and 3 (P < 0.001). In all the groups, any complications observed were transient and minor. Conclusions: The midline and paramedian approaches are technically easier and statistically comparable, but clinically less efficacious than the transforaminal approach. The incidence of ventral spread and nerve root delineation show a definite correlation with clinical improvement. However, an longer follow-up period is advisable for a better evaluation of the actual outcom.

• Journal of the Korean Society for information Management
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• v.22 no.4 s.58
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• pp.23-38
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• 2005

In order to make interactive computing systems, including information systems, usable it is important to bring users into the design process. This article surveys and introduces several major system design approaches that are widely accepted as approaches from a users' perspective. A user model developed by the author is introduced following these existing approaches. This user model is developed from actual users' understanding of their goals and strategies to solve their information needs by using Dervin's Sense-Making Theory with Sense-Making Timeline Interviews. This user model reveals a different timeline from the default menu presentation orders that originally comes with the software. Steps for developing a user model from the Sense-Making Timeline Interviews are suggested for further application and guidelines in developing user models for system design and evaluation.

• Journal of Korean Neurosurgical Society
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• v.48 no.2
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• pp.139-144
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• 2010

Objective : We report our surgical experience in the treatment of 16 consecutive patients with benign craniovertebral junction (CVJ) tumor, observed from 2003 to 2008 at our department. Methods : We had treated 6 foramen magnum meningiomas, 6 cervicomedullary hemangioblastomas, 1 accessory nerve schwannoma, 1 hypoglossal nerve schwannoma, 1 C2 root schwannoma, and 1 cavernous hemangioma. Clinical results were evaluated by Karnofsky Performance Scale (KPS) and all patients underwent preoperative neuroradiological evaluation with computed tomography (CT) and magnetic resonance image (MRI). Angiography was performed in 15 patients and preoperative embolization was done in 2 patients. Results : Five far-lateral, 1 supracondylar and 10 midline suboccipital approaches were performed. Gross total removal was achieved in 15 cases (94%) and subtotal removal in 1 patient (6%). None of the patients required occipitocervical fusion. Radiological follow-up showed no recurrence in cases totally removed. Postoperative decrease of KPS scores was recorded in only 1 patient. The treatment of cervicomedullary solid hemangioblastoma presented particular issues : by preoperative embolization, we removed tumor totally without an excessive bleeding or brainstem injury. In one of foramen magnum meningioma, we carried out subtotal removal due to hard tumor consistency and encasement of neurovascular structures. Conclusion : The choice of surgical approaches and the extent of bone resection should be defined according to the location and size of individual tumors. Moreover, we emphasize that preoperative neuroradiological evaluations on presumptive tumor type could be helpful to the surgeon in tailoring the technique and providing the required exposure for different lesions, without unnecessary surgical steps.

• Journal of KIISE:Databases
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• v.36 no.5
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• pp.374-385
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• 2009

Flash memory becomes increasingly popular as data storage for various devices because of its versatile features such as non-volatility, light weight, low power consumption, and shock resistance. Flash memory, however, has some distinct characteristics that make today's disk-based database technology unsuitable, such as no in-place update and the asymmetric speed of read and write operations. As a result, most traditional disk-based database systems may not provide the best attainable performance on flash memory. To maximize the database performance on flash memory, some approaches have been proposed where only the changes made to the database, i.e., logs, are written to another empty place that has born erased in advance. In this paper, we propose an efficient log management scheme for flash-based database systems. Unlike the previous approaches, the proposed approach stores logs in specially allocated blocks, called log blocks. By evenly distributing logs across log blocks, the proposed approach can significantly reduce the number of write and erase operations. Our performance evaluation shows that the proposed approaches can improve the overall system performance by reducing the number of write and erase operation compared to the previous ones.

• Asian Pacific Journal of Cancer Prevention
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• v.13 no.5
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• pp.2419-2423
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• 2012

Context: Genuine community participation does not denote taking part in an action planned by health care professionals in a medical or top-down approach. Further, community participation and health education on breast cancer prevention are not similar to other activities incorporated in primary health care services in Iran. Objective: To propose a model that provides a methodological tool to increase women's participation in the decision making process towards breast cancer prevention. To address this, an evaluation framework was developed that includes a typology of community participation approaches (models) in health, as well as five levels of participation in health programs proposed by Rifkin (1985&1991). Method: This model explains the community participation approaches in breast cancer prevention in Iran. In a 'medical approach', participation occurs in the form of women's adherence to mammography recommendations. As a 'health services approach', women get the benefits of a health project or participate in the available program activities related to breast cancer prevention. The model provides the five levels of participation in health programs along with the 'health services approach' and explains how to implement those levels for women's participation in available breast cancer prevention programs at the local level. Conclusion: It is hoped that a focus on the 'medical approach' (top-down) and the 'health services approach' (top-down) will bring sustainable changes in breast cancer prevention and will consequently produce the 'community development approach' (bottom-up). This could be achieved using a comprehensive approach to breast cancer prevention by combining the individual and community strategies in designing an intervention program for breast cancer prevention.

• Archives of Plastic Surgery
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• v.35 no.2
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• pp.152-158
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• 2008

Purpose: Mandibulotomy approach and mandible sparing approach are most common methods for oropharyngeal cancer surgery. Good surgical view and convenience of flap inset are advantages of mandibulotomy approach but deformity of mandible contour, postoperative malocclusion and radionecrosis are its limitations. To make up for the limitations, mandible sparing method is commonly performed, but limited surgical view and difficulties of flap inset are the weak points of this approach. The purpose of the study is to compare mandibulotomy and mandible sparing approaches in postoperative complications and progression of the treatment in oropharyngeal cancer operation and reconstruction. Methods: Single reconstructive microsurgeon operated for oropharyngeal cancer patients with different surgeons of head and neck department who prefer mandibulotomy and mandible sparing approach respectively, and we compared the frequency of postoperative complication, operation time, duration of hospitalization and recurrence rate between two different surgical approaches. Results: Mandibulotomy approach was used in 18 patients and mandible sparing approach was used in 15 patients. In mandibulotomy approach, there happened one case of teeth injury and one case of necrosis of skin and gingiva, but there happened no malocclusion and radionecrosis. In mandible sparing approach, there were 3 cases of fistula and 2 cases of infection which are significantly higher than mandibulotomy approach. There were no significant differences between early regional recurrence and duration of hospitalization. Conclusion: In this study we compared two different methods for the surgical approach in oropharyngeal cancer surgery. As mandible sparing approach has difficulties of limited surgical view, it can be used for the limited indications of anterior tongue and mouth floor cancer. Mandibulotomy approach has advantages of good surgical view and convenience of flap inset. In this method preservation of gingival tissue, watertight fashion suture, delicate osteotomy and plate fixation to maintain occlusion are the key points for the successful results.

• Journal of Korea Water Resources Association
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• v.49 no.2
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• pp.165-175
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• 2016

In order to examine the applicability, the evaporation estimation approaches based on solar radiation are classified into 3 different model groups (Model groups A, B, and C) in this study. Each group is tested in the 6 study stations (Seoul, Daejeon, Jeonju, Busan, Mokpo, and Jeju). The model parameters of each model group are estimated and verified with measured pan evaporation data. The applicability of verified model groups are compared with results of Penman (1948) combination approach. Nash-Sutcliffe (N-S) efficiency coefficients greater than 0.663 in all study stations indicate satisfactory estimates of evaporation. On the other hand, in the model verification process, N-S efficiency coefficients greater than 0.526 in all study stations indicate also satisfactory estimates of evaporation. However, N-S efficiency coefficients in all study cases except Model groups B and C in Busan are less than those of Penman (1948) combination approach. Therefore, it is concluded in this study that the evaporation estimation approaches based on solar radiation have capability to replace Penman (1948) combination approach for the estimation of evaporation in case that some meteorological data (wind speed, relative humidity) are missing or not measured.