• Bulletin of the Korean Chemical Society
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• v.23 no.2
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• pp.337-345
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• 2002

The equilibrium structures for the ground and transition states of $C_7H_7^+$ isomers have been investigated using sophisticated ab initio quantum mechanical techniques with various basis sets. The structures of tropyrium and benzyl cations have been fully optimized at the DZP CCSD(T) levels of theory. And the structures of o-, m-and p-tolyl cations are optimized fully up to the DZ CCSD(T) levels of theory. The geometries for the transition states between three isomers of tolyl cations have been optimized up to DZP CISD level of theory. The SCF harmonic vibrational frequencies for tropylium, benzyl, and three isomers of tolyl cations are all real numbers, which confirm the potential minima and each unique imaginary vibrational frequencies for TS1 and TS2 confirm the true transition states. The relative energy of the benzyl cation with respect to the tropyrium cation is predicted to be 28.5 kJ/mol and is in good agreement with the previous theoretical predictions. The 0 K heats of formation, ${\Delta}H^{\circ}_{f0}$, have been predicted to be 890, 1095, 1101, and 1110 kJ/mol for tropylium, ortho-, meta-, and para-tolyl cations by taking the experimental value of 919 kJ/mol for the benzyl cation as the base level. The relative stability between tolyl cations is in the order of ortho

• Korean Journal of Health Education and Promotion
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• v.24 no.4
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• pp.131-147
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• 2007

As overweight and obese people have increased, obesity management programs have generated much concern in Korea. Many types of obesity management programs were operated, aimed at reducing weight, BMI, body fat percentage and so on. This study was conducted to review the features of studies in obesity management programs and systematically assess the effects which were published from 1995 to 2006 in Korea. Databases were systematically searched for published data in Korea. It were KISS (Korean studies information services system) and KERIS (Korean Education research information system), which were major literature search systems for all academic fields in Korea. Total 114 studies were initially identified, of which 21 satisfied our inclusion data. The effects of obesity management programs were assessed on the results in weight, BMI (body mass index), HDL (high density lipids), body fat percentage, self-efficacy. Effect size estimated on the equation of M1 - M2 / Sp, where M1 was mean of the experimental group, M2 was the mean of control group, and Sp was the pooled standard deviation. Magnitude of effect size was interpreted by using Cohen's definition. Cohen described small, medium, and large effect sizes as 0.2, 0.5, and 0.8 respectively. The studies about obesity management programs were the most published in 2005(26.1%). Obesity management programs were popularly operated as the type of 12 weeks intervention, exercise intervention(52.4%), quasi-experimental study(85.7%). Ten studies reported significant effects on weight, and nine studies reported significant effects on BMI and HDL. Only five and three studies reported significant effects on body fat percentage and self-efficacy respectively. The effects of each outcome were generally significant when the studies included these elements, intervention over 10 weeks, evaluation over 3 times, a comprehensive program (exercise, nutrition education, behavior modification) and reinforcing factors (self-monitoring, group discussion, one's goal setting, and etc.). Effective obesity management programs should contain these essential elements and objectives of obesity management programs must be set out evident at the beginning. The participants should be registered, educated and evaluated by continuous obesity management programs.

• KIPS Transactions on Software and Data Engineering
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• v.3 no.12
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• pp.523-530
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• 2014

Ontology alignment is the way to share and reuse of ontology knowledge. Because of the ambiguity of concept, most ontology alignment systems combine a set of various measures and complete enumeration to provide the satisfactory result. However, calculating process becomes more complex and required time increases exponentially since the number of concept increases, more errors can appear at the same time. Lately the focus is on meta-matching using the heuristic algorithm. Existing meta-matching system tune extra parameter and it causes complex calculating, as a consequence, the results in the various data of specific domain are not good performed. In this paper, we propose a high performance algorithm by using DCS that can solve ontology alignment through simple process. It provides an efficient search strategy according to distribution of Levy Flight. In order to evaluate the approach, benchmark data from the OAEI 2012 is employed. Through the comparison of the quality of the alignments which uses DCS with state of the art ontology matching systems.

• Journal of Korean Society of Rural Planning
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• v.19 no.2
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• pp.193-202
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• 2013

This study aims at suggesting some measures to establish rural community development information system through ISP. A future model for rural community development information system was established by applying such 3-step ISP methodology as environment analysis, current status(AS-IS) analysis, future(To-Be) directions. As a result, with the vision of realizing comprehensive information service for rural development projects, rural development information system has established such goals as the assistance of project decision making through preparing rural development project data management system and acquiring evaluation efficiency, the preparation of spatial information utilization system, the utilization of objective GIS-based information through the increase of data management efficiency, the community activation and participatory rural development through rural spatial information portal service. In order to attain the goals, four strategical subject matters were derived. They are: 1) one-stop service subject matter for data management including pilot DB building for rural development projects, 2) rural information GIS service strengthening subject matter including DB building for rural development, O&M measures, 3) step-by-step DB building subject matter including the sharing of integrated information system for rural development, and 4) core value increase subject matter of spatial information data including the building of active service delivery system.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.40 no.1
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• pp.95-104
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• 2017

This paper deals with solution methods for discrete and multi-valued optimization problems. The objective function of the problem incorporates noise effects generated in case that fitness evaluation is accomplished by computer based experiments such as Monte Carlo simulation or discrete event simulation. Meta heuristics including Genetic Algorithm (GA) and Discrete Particle Swarm Optimization (DPSO) can be used to solve these simulation based multi-valued optimization problems. In applying these population based meta heuristics to simulation based optimization problem, samples size to estimate the expected fitness value of a solution and population (particle) size in a generation (step) should be carefully determined to obtain reliable solutions. Under realistic environment with restriction on available computation time, there exists trade-off between these values. In this paper, the effects of sample and population sizes are analyzed under well-known multi-modal and multi-dimensional test functions with randomly generated noise effects. From the experimental results, it is shown that the performance of DPSO is superior to that of GA. While appropriate determination of population sizes is more important than sample size in GA, appropriate determination of sample size is more important than particle size in DPSO. Especially in DPSO, the solution quality under increasing sample sizes with steps is inferior to constant or decreasing sample sizes with steps. Furthermore, the performance of DPSO is improved when OCBA (Optimal Computing Budget Allocation) is incorporated in selecting the best particle in each step. In applying OCBA in DPSO, smaller value of incremental sample size is preferred to obtain better solutions.

• The Korean Journal of Nuclear Medicine Technology
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• v.21 no.2
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• pp.65-73
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• 2017

Purpose 3D 프린팅 기술은 3D 스캔이나 모델링을 통하여 적측가공 방식으로 제작하는 기공기술로서 금형 없이 직접 생산이 가능하고 빠른 시간 내에 제작이 가능하여 최근 다양한 산업분야에서 본격적으로 적용되고 있다. 3D 프린팅 기술은 의료분야에 있어, 영상의학 및 방사선 치료분야에서 다양하게 활용되고 있지만 핵의학 분야에서는 관련 연구가 미비한 실정이다. 그러므로 본 연구는 기존에 적용되고 있는 핵의학분야 팬텀과 3D 프린팅 기술로 제작된 텀의 특성을 비교하고 적용 가능성을 평가하는데 목적을 두었다. Materials and Methods 방사선 투과도 변화측정 국제기준 팬텀인 알루미늄(Aluminum) 계단 쐐기(step wedge)를 기준($140mm{\times}62mm{\times}35mm$)으로 PMMA(Poly Methyl Meta Acrylate)와 ABS(Acrylonitrile Butadiene Styrene)재질로 각각 동일한 크기의 팬텀을 제작하였다. PMMA 팬텀은 핵의학 분야에서 주로 적용되는 팬텀의 성분과 동일한 소재로 제작하였고, ABS 팬텀 제작은 3D 프린팅 기술의 액체 기반형의 SLA(Stereo Lithography Apparatus)기법을 사용하여 제작하였다. 본 연구는 SPECT/CT장비 BrightView XCT(Philips Health Care, Cleveland, USA)를 이용하였다. 영상 획득은 Rectangular Flood phantom(Biodex, New York, USA) $^{99m}TcO_4$ 3, 6 mCi와 $^{57}Co$ lood phantom(adqual, New Hampshire, USA) $^{57}Co$ 20 mCi를 이용하여 Aluminum, PMMA, ABS 팬텀에 대해 60 min 리스트모드(List mode)로 획득하였다. 획득한 영상의 분석을 위해 관심영역(ROI)을 설정하여 각 팬텀의 단계별로 평가하였다. Results 방사선원의 종류 및 방사선량에 따라 ABS 팬텀의 계수치는 PMMA 팬텀의 계수치와 유사한 값을 나타내며, 두께의 증가에 따라 선형적으로 감소하였다. Aluminum, PMMA, ABS 팬텀의 선감약계수를 비교했을 때, Aluminum 팬텀의 선감약계수는 나머지 두 팬텀보다 수치가 높았고, PMMA, ABS 팬텀에서는 근사치의 선감약계수가 나타났다. Conclusion 3D 프린팅 기술로 제작된 ABS 팬텀을 기준으로 PMMA 팬텀은 두께가 증가함에 따른 계수치의 변화가 유사하게 선형적으로 감소하였고, 선감약계수도 근사치로 나타내었다. ABS 팬텀의 핵의학적 적용 가능성을 확인할 수 있었으며, 추후 연구를 통해 세부적인 교정치(correction value)를 적용한다면 활발한 적용이 가능하리라 사료된다.

• The Korean Journal of Applied Statistics
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• v.26 no.3
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• pp.453-470
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• 2013

In this paper, we consider a Bayesian analysis of the dose-effect relationship of cadmium to evaluate a benchmark dose(BMD). For this purpose, two dose-response curves commonly used in the toxicity study are fitted based on Bayesian methods to the data collected from the scientific literature on cadmium toxicity. Specifically, Bayesian meta-analysis and hierarchical modeling build an overall dose-effect relationship that use a piecewise linear model and Hill model, where the inter-study heterogeneity and inter-individual variability of dose and effect such as gender, age and ethnicity are accounted. Estimation of the unknown parameters is made by using a Markov chain Monte Carlo algorithm based user-friendly software WinBUGS. Benchmark dose estimates are evaluated for various cut-offs and compared with different tested subpopulations with with gender, age and ethnicity based on these two Bayesian hierarchical models.

• Journal of International Academy of Physical Therapy Research
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• v.11 no.2
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• pp.2096-2101
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• 2020

Background: The effect of mobilization on lumbar back pain has been fully described in several clinical aspects, but evidence for muscle strength would be still less clear. Objective: To assess the effect of lumbar mobilization on lower limb strength in healthy individuals. Methods and Analysis: Healthy people aged 18-65 will be included regardless of race or sex. Original peer-reviewed primary reporting randomized controlled trials (RCTs) will be included. Electronic databases, such as MEDLINE, EMBASE, Cochrane Central Register of Controlled Trials, Web of Science, Pedro, CINAHL, ClinicalTrials.gov will be searched from inception until July 30. Only studies published in English will be included in this review. Two reviewers will complete the screening for eligibility independently, and the other two reviewers will also complete the risks of data extraction and bias assessment independently. Lower Limb strength will be assessed as primary outcome, and particular intervention or participant characteristics will be assessed as the secondary outcomes. Meta-analysis will be conducted using Review Manager 5.3.3, and evidence level will be assessed using the method for Grading of Recommendations Assessment, Development and Evaluation. Outcomes will be presented as the weighted mean difference or standardized mean difference with 95% CI. If I² ≤ 50%, P>.1, the fixed effect model will be used, otherwise, random-effects model will be used. Ethics and dissemination: This review might not be necessary ethical approval because it does not require individual patient's data; these findings will be published in conference presentations or peer-reviewed journal articles. PROSPERO registration number: CRD42020150144.

• Restorative Dentistry and Endodontics
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• v.45 no.3
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• pp.26.1-26.18
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• 2020

Objectives: This study aimed to systematically review the pain and flare-up effects of calcium hydroxide (CH) as intracanal medication (ICM) in non-vital mature teeth. Materials and Methods: Electronic-databases searching for published and grey literature and manual searching were conducted. Only randomized clinical trials (RCTs) were included comparing CH to other ICMs in non-vital mature teeth. The risk of bias was assessed using the RoB 2.0 Cochrane tool. The main outcomes were pain and flare-up. Qualitative and quantitative analysis, wherever applicable, was performed. The certainty of evidence (CoE) was assessed using Grading of Recommendations Assessment, Development and Evaluation (GRADE). Results: Sixteen articles were included in 6 comparisons at different time points for different outcomes. CH reduced pain risk than no ICM within the 1-14-days interval (p < 0.05) and than triple-antibiotic paste within the first day (p < 0.05) and was similar to corticosteroid/antibiotics combination (p > 0.05). Chlorhexidine (CHX) or CH/CHX, however, reduced pain levels than CH alone (p < 0.05). CH showed higher flare-up risk than CHX (p < 0.05). CoE, however, ranged from very low to moderate. Conclusion: Most comparisons for different outcomes are based on very few studies, mostly low-powered, with an overall low CoE. Thus, the available evidence is considered insufficient to either support or refute CH effectiveness or to recommend one ICM over another. Therefore, further well-designed, larger RCTs are required.

• Clinical and Experimental Pediatrics
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• v.64 no.11
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• pp.575-581
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• 2021

Background: Toxocariasis is a zoonotic parasitic disease caused by Toxocara canis and Toxocara cati in humans. Various types of T. canis are important. Purpose: The current study aimed to investigate the prevalence of Toxocara spp. in pediatrics in the context of a systematic review and meta-analysis. Methods: The MEDLINE (PubMed), Web of Sciences, Embase, Google Scholar, Scopus, and Cumulative Index of Nursing and Allied Health databases were searched to identify peer-reviewed studies published between January 2000 and December 2019 that report the prevalence of Toxocara spp. in pediatrics. The evaluation of articles based on the inclusion and exclusion criteria was performed by 2 researchers individually. Results: The results of 31 relevant studies indicated that the prevalence of Toxocara spp. was 3%-79% in 10,676 cases. The pooled estimate of global prevalence of Toxocara spp. in pediatrics was 30 (95% confidence interval, 22%-37%; I²=99.11%; P=0.00). The prevalence was higher in Asian populations than in European, American, and African populations. Conclusion: Health policymakers should be more attentive to future research and approaches to Toxocara spp. and other zoonotic diseases to improve culture and identify socioeconomically important factors.