• Journal of Internet Computing and Services
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• v.24 no.1
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• pp.61-69
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• 2023

Recently, as the fishery resources are depleted, expectations for productivity improvement by 'rearing fishery' in land farms are greatly rising. In the case of land farms, unlike ocean environments, it is easy to control and manage environmental and breeding factors, and has the advantage of being able to adjust production according to the production plan. On the other hand, unlike in the natural environment, there is a disadvantage in that operation costs may significantly increase due to the artificial management for fish growth. Therefore, profit maximization can be pursued by efficiently operating the farm in accordance with the planned target shipment. In order to operate such an efficient farm and nurture fish, an accurate growth prediction model according to the target fish species is absolutely required. Most of the growth prediction models are mainly numerical results based on statistical analysis using farm data. In this paper, we present a growth prediction model from a stochastic point of view to overcome the difficulties in securing data and the difficulty in providing quantitative expected values for inaccuracies that existing growth prediction models from a statistical point of view may have. For a stochastic approach, modeling is performed by introducing a Gaussian process regression method based on water temperature, which is the most important factor in positive growth. From the corresponding results, it is expected that it will be able to provide reference values for more efficient farm operation by simultaneously providing the average value of the predicted growth value at a specific point in time and the confidence interval for that value.

• Korean Journal of Radiology
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• v.23 no.6
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• pp.615-624
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• 2022

Objective: To compare the therapeutic outcomes of laparoscopic hepatic resection (LHR) and laparoscopic radiofrequency ablation (LRFA) for single subcapsular hepatocellular carcinoma (HCC). Materials and Methods: We screened 244 consecutive patients who had received either LHR or LRFA between January 2014 and December 2016. The feasibility of LRFA in patients who underwent LHR was retrospectively assessed by two interventional radiologists. Finally, 60 LRFA-feasible patients who had received LHR and 29 patients who had received LRFA as the first treatment for a solitary subcapsular HCC between 1 cm and 3 cm were finally included. We compared the therapeutic outcomes, including local tumor progression (LTP), recurrence-free survival (RFS), and overall survival (OS) between the two groups before and after propensity score (PS) matching. Multivariable Cox proportional hazard regression was also used to evaluate the difference in OS and RFS between the two groups for all 89 patients. Results: PS matching yielded 23 patients in each group. The cumulative LTP and OS rates were not significantly different between the LHR and LRFA groups after PS matching (p = 0.900 and 0.003, respectively). The 5-year LTP rates were 4.6% and 4.4%, respectively, and OS rates were 100% and 90.7%, respectively. The RFS rate was higher in LHR group without statistical significance (p = 0.070), with 5-year rates of 78.3% and 45.3%, respectively. OS was not significantly different between the LHR (reference) and LRFA groups in multivariable analyses, with a hazard ratio (HR) of 1.33 (95% confidence interval, 0.12-1.54) (p = 0.818). RFS was higher in LHR (reference) than in LRFA without statistical significance in multivariable analysis, with an HR of 2.01 (0.87-4.66) (p = 0.102). Conclusion: There was no significant difference in therapeutic outcomes between LHR and LRFA for single subcapsular HCCs measuring 1-3 cm. The difference in RFS should be further evaluated in a larger study.

• Annals of Occupational and Environmental Medicine
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• v.34
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• pp.40.1-40.9
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• 2022

Background: According to the occupational accident status analysis in 2020, of 1,180 occupational deaths, 463 were caused by cardiovascular disease (CVD). Workers should be assessed for CVD risk at regular intervals to prevent work-related CVD in accordance with the rules on occupational safety and health standards. However, no previous study has addressed risk and mortality. Therefore, this longitudinal study was conducted to evaluate the relationship between 10-year cardiovascular risk of the general health checkup and mortality. Methods: The study included 545,859 participants who visited Kangbuk Samsung Total Healthcare Centers from January 1, 2002, to December 31, 2017. We performed 10-year cardiovascular risk assessment for the participants and the risk was divided into 4 groups (low, moderate, high, and very high). The study used death data from the Korea National Statistical Office for survival status as an outcome variable by December 31, 2019, and the cause of death based on the International Classification of Diseases, 10^th Revision (ICD-10) was identified. Statistical analysis was performed using Cox proportional hazards regression analysis, and the sum of the periods from the first visit to the date of death or December 31, 2019, was used as a time scale. We also performed a stratified analysis for age at baseline and sex. Results: During 5,253,627.9 person-years, 4,738 overall deaths and 654 cardiovascular deaths occurred. When the low-risk group was set as a reference, in the multivariable-adjusted model, the hazard ratios (HRs) (95% confidence interval [CI]) for overall mortality were 3.36 (2.87-3.95) in the moderate-risk group, 11.08 (9.27-13.25) in the high-risk group, and 21.20 (17.42-25.79) in the very-high-risk group, all of which were statistically significant. In cardiovascular deaths, the difference according to the risk classification was more pronounced. The HRs (95% CI) were 8.57 (4.95-14.83), 38.95 (21.77-69.69), and 78.81 (42.62-145.71) in each group. As a result of a subgroup analysis by age and sex, the HRs of all-cause mortality and cardiovascular mortality tended to be higher in the high-risk group. Conclusions: This large-scale longitudinal study confirmed that the risk of death increases with the 10-year cardiovascular risk of general health checkup.

• Progress in Medical Physics
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• v.25 no.2
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• pp.65-71
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• 2014

A Varian Portal Dosimetry system was compared to an isocentrically mounted MapCHECK 2 diode array for volumetric modulated arc therapy (VMAT) QA. A Varian TrueBeam STx with an aS-1000 digital imaging panel was used to acquire VMAT QA images for 13 plans using four photon energies (6, 8, 10 and 15 MV). The EPID-based QA images were compared to the Portal Dose Image Prediction calculated in the Varian Eclipse treatment planning system (TPS). An isocentrically mounted Sun Nuclear MapCHECK 2 diode array with 5 cm water-equivalent buildup was also used for the VMAT QAs and the measurements were compared to a composite dose plane from the Eclipse TPS. A ${\gamma}$ test was implemented in the Sun Nuclear Patient software with 10% threshold and absolute comparison at 1%/1 mm (dose difference/distance-to-agreement), 2%/2 mm, and 3%/3 mm criteria for both QA methods. The two-tailed paired Student's t-test was employed to analyze the statistical significance at 95% confidence level. The average ${\gamma}$ passing rates were greater than 95% at 3%/3 mm using both methods for all four energies. The differences in the average passing rates between the two methods were within 1.7% and 1.6% of each other when analyzed at 2%/2 mm and 3%/3 mm, respectively. The EPID passing rates were somewhat better than the MapCHECK 2 when analyzed at 1%/1 mm; the difference was lower for 8 MV and 10 MV. However, the differences were not statistically significant for all criteria and energies (p-values >0.05). The EPID-based QA showed large off-axis over-response and dependence of ${\gamma}$ passing rate on energy, while the MapCHECK 2 was susceptible to the MLC tongue-and-groove effect. The two fluence-based QA techniques can be an alternative tool of VMAT QA to each other, if the limitations of each QA method (mechanical sag, detector response, and detector alignment) are carefully considered.

• The Korean Journal of Applied Statistics
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• v.23 no.1
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• pp.1-11
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• 2010

This study aims to improve the more confident and efficient projection method that is to estimate the Number of Household per Family scales(NHF) in projecting the Household Heath care Expenditure(HHE). For this purpose, this paper suggested three results of the research. First, because projecting the NHF does not reflect the recent socio-demographic trends in the process of projecting the National Health Expenditure(NHE),the prior projection results have serious problem in the confidence and political availability. Second, the projection results about the HHE might be underestimated relative to the real one. Third, in order to estimate the more confident and efficient estimates of the HHE, the estimated NHF reflecting the socio-demographic trend must be used to project the one. There is an alternative method that the NHF and the increasing or decreasing rate of them which are regularly surveyed and suggested by the KOSIS should be used to project the process.

• Parasites, Hosts and Diseases
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• v.50 no.1
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• pp.23-27
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• 2012

The aim of this study is to ascertain the relationship between ingestion of raw cow liver and $Toxocara$ $canis$ infection. A total of 150 apparently healthy adults were divided into 2 groups; 1 group consisted of 86 adults with positive results of Toxocara ELISA, and the other group of 64 adults with negative results. One researcher collected the history of ingestion of raw cow liver within 1 year and recent history of keeping dogs. Among 86 seropositive adults for $T.$ $canis$, 68 (79.1%) had a recent history of ingestion of raw cow liver. Multivariate statistical analysis showed that a recent ingestion of raw cow liver and keeping dogs were related to an increased risk of toxocariasis (odds ratios, 4.4 and 3.7; and 95% confidence intervals, 1.9-10.2 and 1.2-11.6, respectively). A recent history of ingestion of raw cow liver and keeping dogs was significantly associated with toxocariasis.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.4
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• pp.2453-2459
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• 2013

Bevacizumab has been approved for use in combination with chemotherapy to treat many types of cancer but associated neutropenic events, including febrile neutropenia, have been reported. To estimate the incidence and relative risk of neutropenic events in cancer patients treated with bevacizumab combination therapy, we searched PubMed, EMBASE, and Web of Science literature databases, as well as abstracts presented at the American Society of Clinical Oncology conferences, to identify relevant studies published from January 1966 to December 2011. Studies that compared bevacizumab plus chemotherapy or biological therapy with chemotherapy or biological therapy alone, and that had adequate safety data profiles, were selected for analysis. Statistical analyses were conducted to calculate the summary incidence rates, relative risks (RRs), and 95% confidence intervals (CIs) using fixed- or random-effects models. A total of 22 clinical trials involving 15,056 patients were included in the analysis. The summary incidences of high-grade neutropenia (HGN) and high-grade febrile neutropenia (HGFN) in patients receiving bevacizumab was 27.3% (95% CI: 26.4%-28.3%) and 3.91% (95% CI: 3.51%-4.37%), respectively. The risks of HGN (RR=1.10; 95% CI: 1.02-1.19; P=0.02) and HGFN (RR=1.31; 95% CI: 1.08-1.59; P=0.005) were significantly increased in bevacizumab-treated patients, compared to those who did not receive bevacizumab. The RR of bevacizumab-associated HGN, but not HGFN, varied significantly with tumor types (P=0.005). The increased risk of bevacizumab-associated neutropenic events was dose-dependent, as the RR was greater at a dose of 5 mg/kg/week than at 2.5 mg/kg/week. Our findings suggest that bevacizumab addition to cancer therapy significantly increases the risk of serious neutropenic events, and this risk may be dose-dependent.

• The Journal of the Korea Contents Association
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• v.12 no.10
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• pp.541-554
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• 2012

This study suggests the effectiveness of G-learning English afterschool classes implemented to elementary school students at low achievement level in English. These days, the use of games in teaching and learning, known as G-learning, has gradually expanded, so it is necessary to consider how to adapt G-learning generally in English education. A G-learning afterschool English class was implemented to 23 low-level 5th grade students in an elementary school located in Daejon for 12 weeks. This study set two hypotheses aiming to determine the effectiveness in achievement and affectiveness of the participants. Pre and post achievement tests were conducted. Also, survey and FGI (focused group interview) were carried out twice with the participants. The study found that students' spelling awareness, vocabulary recognition and dialogue comprehension ability (hypothesis 1) were all improved with statistical significance. Moreover, after the class, participants' confidence and interest toward English study showed meaningful increases.

• Journal of Preventive Medicine and Public Health
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• v.45 no.5
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• pp.316-322
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• 2012

Objectives: Abdominal obesity increases mortality and morbidity from cardiovascular disease and there is a possibility that smoking effects obesity. However, previous studies concerning the effects of smoking on obesity are inconsistent. The objective of this study was to examine whether smoking is positively related to abdominal obesity in men with type 2 diabetes. Methods: Subjects consisted of 2197 type 2 diabetic patients who visited Huh's Diabetes Center from 2003 to 2009. Indices of abdominal obesity were defined as visceral fat thickness (VFT) measured by ultrasonography and waist circumference (WC). Overall obesity was defined as body mass index (BMI). Results: Statistically significant differences in WC and VFT by smoking status were identified. However, there was no statistical difference in BMI according to smoking status. Means of WC and VFT were not significantly higher in heavy smokers and lower in mild smokers. Compared to nonsmokers, the BMI confounder adjusted odds ratio and 95% confidence interval for VFT in ex-smokers and current-smokers were 1.70 (1.21 to 2.39) and 1.86 (1.27 to 2.73), respectively. Conclusions: Smoking status was positively associated with abdominal obesity in type 2 diabetic patients.

• Journal of Preventive Medicine and Public Health
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• v.53 no.6
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• pp.455-464
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• 2020

Objectives: The distribution of hospitals in Korea is unbalanced in terms of accessibility. Many local public health centers (PHCs) exempt out-of-pocket payments (OOPs) based on local government laws to increase coverage. However, this varies across administrative regions, as many make this exemption for the elderly, while others do not. This study aimed to evaluate the effects of the OOP exemption at local PHCs among elderly individuals. Methods: This study used online data on Korean national law to gather information on individual local governments' regulations regarding OOP exemptions. Individual-level data were gathered from the 2018 Community Health Survey and regional-level data from public online sources. Results: The study analyzed 132 regions and 44 918 elderly people. A statistical analysis of rate differences and 2-level multiple logistic regression were carried out. The rate difference according to whether elderly individuals resided in areas with the OOP exemption was 1.97%p (95% confidence interval [CI], 1.07 to 2.88) for PHC utilization, 1.37%p (95% CI, 0.67 to 2.08) for hypertension treatment, and 2.19%p (95% CI, 0.63 to 3.74) for diabetes treatment. The regression analysis showed that OOP exemption had an effect on hypertension treatment, with a fixed-effect odds ratio of 1.25 (95% CI, 1.05 to 1.48). Conclusions: The OOP exemption at PHCs can affect medical utilization in Korea, especially for hypertension treatment. The OOP exemption should be expanded to improve healthcare utilization in Korea.