• Journal of Ginseng Research
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• 제42권4호
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• pp.485-495
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• 2018

Background: The geographical origin of Panax ginseng Meyer, a valuable medicinal plant, is important to both ginseng producers and consumers in the context of economic profit and human health benefits. We, therefore, aimed to discriminate between the cultivation regions of ginseng using the stable isotope ratios of C, N, O, and S, which are abundant bioelements in living organisms. Methods: Six Korean ginseng cultivars (3-yr-old roots) were collected from five different regions in Korea. The C, N, O, and S stable isotope ratios in ginseng roots were measured by isotope ratio mass spectrometry, and then these isotope ratio profiles were statistically analyzed using chemometrics. Results: The various isotope ratios found in P. ginseng roots were significantly influenced by region, cultivar, and the interactions between these two factors ($p{\leq}0.001$). The variation in ${\delta}^{15}N$ and ${\delta}^{13}C$ in ginseng roots was significant for discriminating between different ginseng cultivation regions, and ${\delta}^{18}O$ and ${\delta}^{34}S$ were also affected by both altitude and proximity to coastal areas. Chemometric model results tested in this study provided discrimination between the majority of different cultivation regions. Based on the external validation, this chemometric model also showed good model performance ($R^2=0.853$ and $Q^2=0.738$). Conclusion: Our case study elucidates the variation of C, N, O, and S stable isotope ratios in ginseng root depending on cultivation region. Hence, the analysis of stable isotope ratios is a suitable tool for discrimination between the regional origins of ginseng samples from Korea, with potential application to other countries.

• Journal of Periodontal and Implant Science
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• 제36권2호
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• pp.531-554
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• 2006

Oral implants must fulfill certain criteria arising from special demands of function, which include biocompatibility, adequate mechanical strength, optimum soft and hard tissue integration, and transmission of functional forces to bone within physiological limits. And one of the critical elements influencing the long-term uncompromise functioning of oral implants is load distribution at the implant- bone interface, Factors that affect the load transfer at the bone-implant interface include the type of loading, material properties of the implant and prosthesis, implant geometry, surface structure, quality and quantity of the surrounding bone, and nature of the bone-implant interface. To understand the biomechanical behavior of dental implants, validation of stress and strain measurements is required. The finite element analysis (FEA) has been applied to the dental implant field to predict stress distribution patterns in the implant-bone interface by comparison of various implant designs. This method offers the advantage of solving complex structural problems by dividing them into smaller and simpler interrelated sections by using mathematical techniques. The purpose of this study was to evaluate the stresses induced around the implants in bone using FEA, A 3D FEA computer software (SOLIDWORKS 2004, DASSO SYSTEM, France) was used for the analysis of clinical simulations. Two types (external and internal) of implants of 4.1 mm diameter, 12.0 mm length were buried in 4 types of bone modeled. Vertical and oblique forces of lOON were applied on the center of the abutment, and the values of von Mises equivalent stress at the implant-bone interface were computed. The results showed that von Mises stresses at the marginal. bone were higher under oblique load than under vertical load, and the stresses were higher at the lingual marginal bone than at the buccal marginal bone under oblique load. Under vertical and oblique load, the stress in type I, II, III bone was found to be the highest at the marginal bone and the lowest at the bone around apical portions of implant. Higher stresses occurred at the top of the crestal region and lower stresses occurred near the tip of the implant with greater thickness of the cortical shell while high stresses surrounded the fixture apex for type N. The stresses in the crestal region were higher in Model 2 than in Model 1, the stresses near the tip of the implant were higher in Model 1 than Model 2, and Model 2 showed more effective stress distribution than Model.

• 사상체질의학회지
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• 제33권3호
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• pp.1-15
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• 2021

Introduction The clinical usefulness of Sasang Digestive Function Inventory (SDFI) for analyzing Sasang type-specific pathophysiological symptom was illustrated repeatedly. It was revised to enhance its validity, reliability and clinical usefulness, however its clinical studies supporting these were not sufficient yet. Methods 193 healthy university students responded once to Nepean Dyspepsia Index-Korean (NDIK), Functional Dyspepsia-Related Quality of Life (FDQOL), and Dutch Eating Behavior Questionnaire (DEBQ), and twice to SDFI with four weeks of interval. The Body Mass Index (BMI) and Ponderal Index (PI) were also calculated. The 4-week test-retest reliability and correlation coefficients between NDIK, FDQOL, DEBQ, and SDFI were examined using Pearson's correlation. The significant differences between Sasang types in SDFI and its subscales were examined using ANCOVA with the age as covariate. Results The range of test-retest reliability for SDFI and its subscales was from 0.801 to 0.887. The SDFI-total correlated positively with BMI (r=0.323) and DEBQ-External Eating (r=0.433), while the SDFI-Digestion negatively with NDIK (r=-0.472) and FDQOL-total (r=-0.364). The SDFI-Habit correlated positively with BMI (r=0.310) and DEBQ-total (r=0.481), and the SDFI-Appetite with DEBQ-total (r=0.322). The SDFI-total, SDFI-Digestion, and SDFI-Habit scores of Tae-Eum type (35.6±6.25, 12.38±3.24 and 9.89±3.38, respectively) were significantly bigger than those of So-Eum type (29.84±8.31, 9.93±4.28 and 7.66±3.96). Discussion The SDFI was found to be an objective clinical measure with sufficient concurrent validity for measuring eating behavior and quality of life related to overeating and dyspepsia, and illustrated distinctive differences between Sasang types. It might be useful for the effective medical education and integrative medical practice.

• 한국BIM학회 논문집
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• 제10권1호
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• pp.9-22
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• 2020

Recently, BIM has been extended to infrastructures such as roads and bridges, and the demand for BIM standard development for ports is increasing internationally. Due to the low level of utilization of classification system and drawing standards compared to other infrastructures, and the closed nature of national security facilities, ports have insufficient level of connection and sharing environment among external systems or users. In addition, since the standardization of data for port facilities is not made, it is still necessary to establish an independent DB for each system and to ensure interoperability of data between these systems since it does not have a shared environment among similar data. Therefore, the purpose of this study is to develop and verify IFC, the international standard for BIM, in order to cope with the BIM environment and to be commonly used in the design, construction, and maintenance of port facilities. To this end, we build a standard schema with port-specific Express Notation according to buildingSMART International's standard development methodology. First, domestic and international reference model standards were analyzed to derive components such as space and facilities of port facilities. Based on this, the components of the port facility were derived through the codification, categorization, and normalization process developed by the research team. This was extended based on the port BIM object classification system developed by the research team. Normalization results were verified by designers and associations. Then, IFC schema construction was based on Express-G data modeling based on IFC 4 * 2 Candidate, which is a bridge candidate standard based on IFC4 (ISO16739), and IFC 4 * 3 Draft, which is developed by buildingSMART International. The final schema was validated using the commercialized validation tool. In addition, in order to verify the structural verification of the port IFC schema, the transformation process was verified by converting the caisson model into a Part21 file. In the future, this result will not only be used as a delivery standard for port BIM products, but will also be applied as a linkage standard between systems and a common data format for port BIM platforms when BIM is used in the maintenance phase. In particular, it is expected to be used as a core standard for data exchange in the port maintenance stage.

• 한국초지조사료학회지
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• 제40권4호
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• pp.259-264
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• 2020

본 연구는 근적외선분광법을 이용하여 국내에서 재배중인 수수×수단그라스 교잡종 품 판별 가능성을 검토하고자 수행되었다. 근적외선분광기를 이용하여 수수×수단그라스 교잡종 종자를 가시파장 대역대 (680 - 1,099 nm), NIRS 파장 대역대 (1,100 - 2,500 nm) 및 NIRS 전체 파장 대역대 (680 - 2,500 nm)로 구분하여 스펙트라를 얻은 후 1차 미분과 8 nm gap으로 수 처리를 수행하였으며 부분최소자승 (PLS) 회귀분석법을 통해 품종판별 검량식을 개발하고 판별 정확성을 검증하였다. 수수×수단그라스 교잡종품종 판별의 정확성은 NIR파장대역에서 SECV 8.44 그리고 R2CV 0.89로 가장 판별 정확성이 낮았으며 NIRS 전체 파장대역에서 SECV 7.88 그리고 R2CV 0.90로 가장 높은 판별 정확성을 나타내었다. 파장대역별 예측 정확성은 NIR 파장대역 (1,100 - 2,500 nm)이 가장 우수하였으며, 교차검증오차 (SECV) 8.44에서 예측오차 (SEP) 12.03로 높아졌으며 가시영역대 (680 - 1,099)는 SECV 8.23에서 SEP 12.51로 높아졌다. Discrimination equation 분석법에 의한 NIRS 전체 파장대역별 수수×수단그라스 교잡종 종자의 판별 결과는 품종간에 판별 정확성의 차이가 크게 나타났으며 1, 2, 4 그리고 8번 품종 (G-7, BMR Gold II, Honey chew and SX-17)에서는 100 %의 정확성으로 가장 높게 나타났다. 따라서 NIRS를 이용한 수수×수단그라스 교잡종 종자의 판별분석이 가능할 것으로 판단되었다.

• 응용통계연구
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• 제35권4호
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• pp.457-468
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• 2022

고령인구가 증가함에 따라 국가차원에서 노인의 건강노화 실현을 위한 장기요양 필요 발생의 예방 방안을 마련하는 것은 매우 중요하며, 정책적 효과를 극대화하기 위해서는 적절한 대상자의 선정이 선행되어야 한다. 이에 본 연구는 국민건강보험공단의 국민건강정보를 활용하여, 장기요양 필요를 야기하는 기능장애 발생 가능성이 높은 대상자를 발굴하기 위한 예측모형을 개발하고자 한다. 본 연구는 연구대상자의 과거 수집된 자료를 활용하는 후향적 연구로, 본 연구의 연구대상자는 만 65세 이상 의료보장등록인구이다(총 7,724,101명). 예측모형 개발을 위해 고유 방법인 로지스틱 회귀모형, 머신러닝 방법인 의사결정나무와 랜덤포레스트, 딥러닝 방법인 다층퍼셉트론 신경망을 분석하였다. 체계적 분석절차를 통해 각 분석방법별 모형을 적합하였고, 내적 타당성 및 외적 타당성 평가 결과를 기반으로 최종 예측모형을 랜덤포레스트로 선정하였다. 랜덤포레스트는 모집단에서의 4.50%밖에 되지 않는 장기요양 필요 대상자의 약 90%를 장기요양 필요 발생 고위험 대상자로 예측할 수 있다. 본 연구의 예측모형 및 고위험군 기준은 노인의 욕구 중심에서 예방 서비스가 필요한 대상자를 선제적으로 발굴하는데 기여할 것으로 기대된다.

• 한국정보전자통신기술학회논문지
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• 제16권5호
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• pp.230-238
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• 2023

식품제조 중소기업들은 원물 투입부터 최종 팔렛타이징까지 대부분 노동집약적이고 수작업으로 구성되어 있다. 최근 로봇과 센서 데이터 기술요소 적용으로 스마트화 디지털화로 변화하는 추세이다. 본 연구에서는 식품제조기업에서 적용 설비 역량보다 작업자가 속도를 따라가지 못하는 반복작업 공정 2가지를 선정하였으며, 이를 3D 시뮬레이션을 활용하여 개선 효과성을 규명하고자 한다. 꼬치 조립 후 작업자들이 계량 후 포장하는 공정과 무작위로 공급되는 냉동식품류를 계량-내·외포장-팔렛타이징 일괄 수작업 공정 2개를 선정하였다. 가동률, 생산량, 투입 작업자 수를 검증 지표로 선정하였다. 3D 개선 공정 시뮬레이션 결과 생산량은 각각 기존보다 13.5%, 56.8% 증가했으며, 특히 팔렛타이징 로봇 적용 공정에서 높은 효과성을 보였다. 두 공정 모두 가동률과 투입인력 수는 감소함에 따라 작업자에게 피로도가 높은 공정을 로봇으로 대체 적용할 수 있어 작업 과부하를 개선할 수 있는 결과를 나타냈다. 본 연구 결과를 바탕으로 3D 시뮬레이션을 활용하여 식품계량 및 포정 공정에 로봇을 도입함으로써 개선된 공정의 성능을 정량적으로 사전 검증의 가능성을 확인할 수 있었다.

• Korean Journal of Radiology
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• 제23권1호
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• pp.77-88
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• 2022

Objective: Our study aimed to evaluate the quality of radiomics studies on brain metastases based on the radiomics quality score (RQS), Transparent Reporting of a multivariable prediction model for Individual Prognosis Or Diagnosis (TRIPOD) checklist, and the Image Biomarker Standardization Initiative (IBSI) guidelines. Materials and Methods: PubMed MEDLINE, and EMBASE were searched for articles on radiomics for evaluating brain metastases, published until February 2021. Of the 572 articles, 29 relevant original research articles were included and evaluated according to the RQS, TRIPOD checklist, and IBSI guidelines. Results: External validation was performed in only three studies (10.3%). The median RQS was 3.0 (range, -6 to 12), with a low basic adherence rate of 50.0%. The adherence rate was low in comparison to the "gold standard" (10.3%), stating the potential clinical utility (10.3%), performing the cut-off analysis (3.4%), reporting calibration statistics (6.9%), and providing open science and data (3.4%). None of the studies involved test-retest or phantom studies, prospective studies, or cost-effectiveness analyses. The overall rate of adherence to the TRIPOD checklist was 60.3% and low for reporting title (3.4%), blind assessment of outcome (0%), description of the handling of missing data (0%), and presentation of the full prediction model (0%). The majority of studies lacked pre-processing steps, with bias-field correction, isovoxel resampling, skull stripping, and gray-level discretization performed in only six (20.7%), nine (31.0%), four (3.8%), and four (13.8%) studies, respectively. Conclusion: The overall scientific and reporting quality of radiomics studies on brain metastases published during the study period was insufficient. Radiomics studies should adhere to the RQS, TRIPOD, and IBSI guidelines to facilitate the translation of radiomics into the clinical field.

• Korean Journal of Radiology
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• 제24권11호
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• pp.1151-1163
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• 2023

Objective: To develop a deep-learning-based bone age prediction model optimized for Korean children and adolescents and evaluate its feasibility by comparing it with a Greulich-Pyle-based deep-learning model. Materials and Methods: A convolutional neural network was trained to predict age according to the bone development shown on a hand radiograph (bone age) using 21036 hand radiographs of Korean children and adolescents without known bone development-affecting diseases/conditions obtained between 1998 and 2019 (median age [interquartile range {IQR}], 9 [7-12] years; male:female, 11794:9242) and their chronological ages as labels (Korean model). We constructed 2 separate external datasets consisting of Korean children and adolescents with healthy bone development (Institution 1: n = 343; median age [IQR], 10 [4-15] years; male: female, 183:160; Institution 2: n = 321; median age [IQR], 9 [5-14] years; male: female, 164:157) to test the model performance. The mean absolute error (MAE), root mean square error (RMSE), and proportions of bone age predictions within 6, 12, 18, and 24 months of the reference age (chronological age) were compared between the Korean model and a commercial model (VUNO Med-BoneAge version 1.1; VUNO) trained with Greulich-Pyle-based age as the label (GP-based model). Results: Compared with the GP-based model, the Korean model showed a lower RMSE (11.2 vs. 13.8 months; P = 0.004) and MAE (8.2 vs. 10.5 months; P = 0.002), a higher proportion of bone age predictions within 18 months of chronological age (88.3% vs. 82.2%; P = 0.031) for Institution 1, and a lower MAE (9.5 vs. 11.0 months; P = 0.022) and higher proportion of bone age predictions within 6 months (44.5% vs. 36.4%; P = 0.044) for Institution 2. Conclusion: The Korean model trained using the chronological ages of Korean children and adolescents without known bone development-affecting diseases/conditions as labels performed better in bone age assessment than the GP-based model in the Korean pediatric population. Further validation is required to confirm its accuracy.

• 분석과학
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• 제27권3호
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• pp.172-180
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• 2014

Pyrazole계 살균제 fenpyrazamine은 복숭아 (2.0 mg/kg), 포도 (5.0 mg/kg) 및 감귤 (2.0 mg/kg)에 잔류허용기준이 설정된 신규농약으로 농산물 중 fenpyrazamine 잔류량을 측정하기 위해 고성능 액체크로마토그래프를 이용한 정확하고 신뢰성 있는 효율적인 공정 시험법을 확립하고자 하였다. 추출용매는 acetonitrile로 선정하였으며, 액-액 분배 단계에서 dichloromethane과 물의 분배로 극성불순물을 제거하였고, 정제단계에서는 silica cartridge를 이용하여 hexane/acetone 용매 조성으로 다양한 매트릭스 간섭 물질로부터 fenpyrazamine을 효과적으로 정제할 수 있었다. 확립된 시험법으로 7종의 대표농산물[과일류 (복숭아, 포도, 감귤), 채소류 (고추), 서류 (감자), 콩류 (대두), 곡류 (현미)]에 처리농도 0.05, 0.5, 5.0 mg/kg으로 각각 5 반복의 회수율 실험을 시행한 결과 회수율 범위가 71.8~102.7%이었고, 분석오차가 10% 미만으로 시험법의 정확성을 확인하였으며, LC-MS를 통한 재확인 과정을 수행함으로써 시험법의 신뢰성과 선택성을 확보할 수 있었다. 따라서 본 연구에서 개발한 시험법은 농산물에 잔류하는 fenpyrazamine을 분석하기 위한 공정 시험법으로 활용할 수 있을 것으로 판단된다.