• 대한예방의학회:학술대회논문집
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• 1999.10a
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• pp.267-268
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• 1999

• Korean System Dynamics Review
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• v.11 no.1
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• pp.27-57
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• 2010

This article deals with an ecological-economic analysis of the 'Pasture Project of Kum River', which is the farming plan of mitten crabs using Jichun, a stream of the River Kum where the natural propagation of mitten crabs are blocked because of the estuary dam constructed in 1990. Toward analyzing the ecological and economic effects of the crab releasing and harvesting activities in Jichun, a two-stage cohort model of population dynamics with cannibalistic behaviors and density restrictions in biomathematics is adopted, despite of the current infertility in Kum, considering the opportunity of establishing dam fishways in the near future. This study moreover presents a method of parameter estimation especially with assuming a steady state of the ecosystem, and performs various analyses such as the risk measurement of climate change and the economic value of such fishways.

• 대한예방의학회:학술대회논문집
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• 1998.10b
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• pp.313-314
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• 1998

• Proceedings of the Korean Information Science Society Conference
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• 2004.04b
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• pp.571-573
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• 2004

Speaker verification systems based on multilayer perceptrons (MLPs) have good prospects in reliability and flexibility required as a successful authentication system. However, the poor learning speed of the error backpropagation (EBP) which is representative learning method of MLPs is the major defect to be complemented to achieve real-time user enrollments. In this paper, we implement an MLP-based speaker verification system and apply the existing two methods of the omitting patterns in instant learning (OIL) and the discriminative cohort speakers (DCS) to approach real-time enrollment. An evaluation of the system on a Korean speech database demonstrates the feasibility of the system as a speaker verification system of high performance.

• Archives of Plastic Surgery
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• v.50 no.3
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• pp.254-263
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• 2023

Background The three-dimensional (3D) evaluation of skeletal stability after orthognathic surgery is a time-consuming and complex procedure. The complexity increases further when evaluating the surgery-first orthognathic approach (SFOA). Herein, we propose and validate a simple time-saving method of 3D analysis using a single software, demonstrating high accuracy and repeatability. Methods This retrospective cohort study included 12 patients with skeletal class 3 malocclusion who underwent bimaxillary surgery without any presurgical orthodontics. Computed tomography (CT)/cone-beam CT images of each patient were obtained at three different time points (preoperation [T0], immediately postoperation [T1], and 1 year after surgery [T2]) and reconstructed into 3D images. After automatic surface-based alignment of the three models based on the anterior cranial base, five easily located anatomical landmarks were defined to each model. A set of angular and linear measurements were automatically calculated and used to define the amount of movement (T1-T0) and the amount of relapse (T2-T1). To evaluate the reproducibility, two independent observers processed all the cases, One of them repeated the steps after 2 weeks to assess intraobserver variability. Intraclass correlation coefficients (ICCs) were calculated at a 95% confidence interval. Time required for evaluating each case was recorded. Results Both the intra- and interobserver variability showed high ICC values (more than 0.95) with low measurement variations (mean linear variations: 0.18 mm; mean angular variations: 0.25 degree). Time needed for the evaluation process ranged from 3 to 5 minutes. Conclusion This approach is time-saving, semiautomatic, and easy to learn and can be used to effectively evaluate stability after SFOA.

• Journal of The Korean Society of Integrative Medicine
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• v.11 no.3
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• pp.49-57
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• 2023

Purpose : This study aimed to systematically review the correlation between hand dexterity and cognitive function in the elderly, and summarize various evaluation tests and results analysis methods for manual dexterity tests applied to this population. Methods : We searched published studies in the Korean Studies Information Service System and PubMed databases from January 2013 to March 2023. The main keywords used were "dexterity," "fine motor," "elderly," "cognitive function," and "correlation." A total of 10 studies were selected for analysis from the 1,524 searched articles. The included studies consisted of a cohort study, a longitudinal study, and eight cross-sectional studies which were analyzed for patients, intervention, comparison, and outcomes. Results : Analyzing the qualitative level of 10 studies, 8 articles (80%) were non-randomized two-group studies that provided level II evidence whereas the remaining 2 studies (20%) were non-randomized single-group studies (level III evidence). Therefore, these results indicated that the level of evidence in this field is generally high. The Purdue pegboard test was the most commonly used evaluation test for manual dexterity, and velocity speed was the most frequently employed analysis method. Results indicated that there were significant differences in manual dexterity test between the normal elderly, those with mild cognitive impairment, or dementia. Conclusions : These results can be used as a basis for selecting dexterity test evaluation items and methods to analyze it in the elderly while screening for cognitive impairment. In addition, this study highlights potential areas for future research on the development of manual dexterity evaluation tools and techniques for analysis and the need for more reliable and valid methods for assessing cognitive function in the elderly.

• Journal of Acupuncture Research
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• v.40 no.3
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• pp.252-264
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• 2023

Background: The primary aim of this study is to statistically analyze and compare the difference in treatment outcomes based on the frequency and duration of acupotomy treatment for lumbar disk herniation. Methods: The evaluation of efficacy and safety involved using visual analog scale (VAS), numeric rating scale (NRS), Roland Morris disability questionnaire (RMDQ), EuroQol 5-dimention (EQ-5D), and similar parameters. This was achieved through the establishment of a comparable cohort using propensity score matching. Group A comprised 46 patients who underwent 4 sessions of acupotomy treatment for 2 weeks, while Group B consisted of 15 patients who received 6 acupotomy sessions for 3 weeks. Results: For Group A, the average amount of change in VAS values at weeks 4 and 6 was significantly decreased. However, the average amount of change in RMDQ values was not significant. Notably, the average amount of change of EQ-5D values at week 6 increased significantly. As for Group B, the average amount of change of NRS values in weeks 2 and 3 was significantly decreased. Conversely, the average amount of change in RMDQ and EQ-5D values was not significant. In comparing the 2 groups at the final follow-up, the average amount of change in all evaluation values was not significant. Further, no significant interaction effect was observed in the changes over time in all evaluation values between the 2 groups. Conclusion: This study establishes that there was no statistically significant difference in pain reduction, functional impairment, and quality of life improvement between 2 group.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.5
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• pp.2369-2374
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• 2016

Background: Differentiated thyroid cancer (DTC) is a cancer group that shares molecular and cellular origin but shows different clinical courses and prognoses. Several prognostic factors have been reported for predicting recurrence for individual patients. This literature review aimed to evaluate prognostic scores for predicting recurrence of DTC. Materials and Methods: A search of the MEDLINE database for articles published until December 2015 was carried out using the terms "thyroid neoplasms AND (recurrent OR persistent) AND (score OR model OR nomogram)". Studies were eligible for review if they indicated the development of prognostic scoring models, derived from a group of independent prognostic factors, in predicting disease recurrence in DTC patients. Results: Of the 308 articles obtained, five were eligible for evaluation. Two scoring models were developed for DTC including both papillary and follicular carcinoma, one for papillary carcinoma, and the other two for papillary microcarcinoma. The number of patients included in the score development cohort ranged from 59 to 1,669. The number of evaluated potential prognostic factors ranged from 4 to 25. Tumor-related factors were the most common factors included in the final scores, with cervical lymph node metastases being the most common. Only two studies showed internal validation of the derived score. Conclusions: There is a paucity of prognostic scores for predicting disease recurrence in patients with DTC, in particular for follicular thyroid carcinoma. Several limitations of the created scores were found. Performance of the scores has not been adequately studied. Comprehensive validation in multiple cohorts is recommended before widespread use.

• 대한예방의학회:학술대회논문집
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• 2005.10a
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• pp.437-437
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• 2005

• Radiation Oncology Journal
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• v.37 no.4
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• pp.286-292
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• 2019

Purpose: A mandibular metastasis is uncommon in patients with hepatocellular carcinoma (HCC). We report the clinical features of this rare lesion and evaluate the effectiveness of radiotherapy in affected patients. Materials and Methods: We retrospectively reviewed our institutional medical records for HCC patients who received radiotherapy for bone metastasis, and included cases of mandible metastasis. The clinical features of these cases, and the characteristics and outcomes of the treatments were assessed. Results: A total of 1,498 patients with a bone metastasis from HCC were treated with radiotherapy between July 1998 and April 2012 at our institution. We identified 9 patients (0.6%) in this cohort that received radiotherapy for a mandibular metastasis. The condyle was the most common location of mandibular metastasis. The median radiation dose was 40 Gy (range, 27.5 to 60 Gy), with a daily dose of 2-3 Gy. All of these 9 patients died during a median follow-up of 9 months (range, 1 to 19 months). Symptom relief was achieved in 7 of 8 patients who completed radiotherapy. Tumor size reduction was observed in 2 of 4 patients who underwent radiologic evaluation after radiotherapy. Conclusions: Metastasis to the mandible from HCC has a poor prognosis. Radiotherapy can be an effective local treatment option for symptomatic relief in these cases.