• Journal of radiological science and technology
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• v.33 no.3
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• pp.239-243
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• 2010

Even though clinical use DRE, PSA and TRUS for screening while diagnosing prostate cancer early, however, we cannot achieve to diagnose it accurately by one method. Thus, mutual supplements are strongly required in diagnosis. It means that we should identify relationship between prostate volume and serum PSA under different ages for better diagnosis. The subjects(405 men) visited the department of diagnostic radiology in a general university hospital from January 2008 to December 2008, who was going to take the prostatic evaluation by TRUS. 13 men, who did definite diagnosis of prostate cancer before through biopsy, were excluded in this study. All data were expressed as mean and standard deviations by using SPSS 14.0 package programs and were analyzed by using one-way ANOVA to evaluate the effect of different ages. And Scheffe Post hoc comparison is accomplished in order to make significant difference in prostate volume, PSA and PSAD according to ages. Pearson correlation was used for ages, prostate volume, PSA and PSAD. According to examination, the subjects' prostate volume and serum PSA level increase as person's age. We can see significant difference between group over 70 years and group from 40 and 50 years. Moreover, age, prostate volume and serum PSA have significant positive correlation. Even though we can get variations in serum PSA level by changing prostate volume according to ages, it is worthwhile to mention that more strong association for prostate volume is observed than ages in elevation of serum PSA. Therefore, it is strongly recommended to consider prostate volume weightly when it comes to evaluate for men with elevated PSA level. Finally, TRUS is an excellent extra equipment to diagnose prostate cancer because it can contribute to early diagnose and pertinent treatment of prostate cancer.

• Korean Journal of Health Education and Promotion
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• v.30 no.4
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• pp.99-110
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• 2013

Objectives: This study aimed to investigate factors related to prostate disease and follow-up procedure on health examination program in Gangwon-do. Methods: The studied population was 16,501 male aged 40 or more, who underwent screening tests for prostatic disease in 2011 health examination program designed for the low income residents in Gangwon-do. The screening tests included prostate specific antigen (PSA), international symptom score (IPSS), and maximal flow rate (Qmax). We conducted chi-square test for trend, two independent samples t-test, and binary logistic regression to find out the relationship between prostate cancer or benign prostatic hyperplasia and risk factors such as age, PSA level, and IPSS. Results: The number of subjects who turned out positive for PSA level (> 3.8ng/ml) was 971 men accounting for 5.9%. The result of post survey on them showed that 511 subjects (52.6%) got the urology check-up: 156 (30.5%) were diagnosed as normal, 286 (56.0%) as benign prostatic hyperplasia, and 69 (13.5%) as prostate cancer. The detection rate for prostate cancer was 8.8% when PSA level was between 3.81 and 9.99g/ml, and was 30.6% when PSA level was more than 10.00ng/ml. The rates of further testing varied depending on the communities from 26.7% to 68.2%, which was mainly affected by the role of local health center. Conclusions: Our findings indicate that enhanced quality control of local health center and empowerment of screening agency would increase the effort of coupled institutions between public and private sectors.

• Proceedings of the Korean Nuclear Society Conference
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• 1996.05b
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• pp.493-498
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• 1996

A PC window-based computer code, CONPAS(CONtainment Performance Analysis System), has been developed to integrate the numerical, graphical and results-operation aspects of Level 2 probabilistic safety assessments (PSA) for nuclear power plants automatically. As a main logic for accident progression analysis, it employs a concept of the small containment phenomenological event tree(CPET) helpful to trace out visually individual accident progressions and of the large supporting event tree(LSET) for its detailed quantification. Compared with other existing computer codes for Level 2 PSA, the CONPAS code provides several advanced features: computational aspects including systematic uncertainty analysis, importance analysis, and sensitivity analysis, reporting aspects including tabling and graphic, and user-friend interface.

• Journal of the Korean Society of Safety
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• v.35 no.1
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• pp.97-106
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• 2020

The objective of this paper is to suggest a new quantification method for multi-unit probabilistic safety assessment (PSA) that removes the overestimation error caused by the existing delete-term approximation (DTA) based quantification method. So far, for the actual plant PSA model quantification, a fault tree with negates have been solved by the DTA method. It is well known that the DTA method induces overestimated core damage frequency (CDF) of nuclear power plant (NPP). If a PSA fault tree has negates and non-rare events, the overestimation in CDF drastically increases. Since multi-unit seismic PSA model has plant level negates and many non-rare events in the fault tree, it should be very carefully quantified in order to avoid CDF overestimation. Multi-unit PSA fault tree has normal gates and negates that represent each NPP status. The NPP status means core damage or non-core damage state of individual NPPs. The non-core damage state of a NPP is modeled in the fault tree by using a negate (a NOT gate). Authors reviewed and compared (1) quantification methods that generate exact or approximate Boolean solutions from a fault tree, (2) DTA method generating approximate Boolean solution by solving negates in a fault tree, and (3) probability calculation methods from the Boolean solutions generated by exact quantification methods or DTA method. Based on the review and comparison, a new intersection removal by probability (IRBP) method is suggested in this study for the multi-unit PSA. If the IRBP method is adopted, multi-unit PSA fault tree can be quantified without the overestimation error that is caused by the direct application of DTA method. That is, the extremely overestimated CDF can be avoided and accurate CDF can be calculated by using the IRBP method. The accuracy of the IRBP method was validated by simple multi-unit PSA models. The necessity of the IRBP method was demonstrated by the actual plant multi-unit seismic PSA models.

• Journal of Soil and Groundwater Environment
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• v.11 no.5
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• pp.59-66
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• 2006

Optimal method of radon analysis in groundwater was studied using ultra low-level liquid scintillation counter (ULLLSC) which is well known as an analytical instrument for analyzing the alpha and beta radionuclides in environmental materials. Optimization of pulse shape analyzer (PSA) in operating the LSC was performed with $^{241}Am\;and\;^{90}Sr/^{90}Y$ as well as $^{226}Ra$ Also, the chemical quenching of scintillation generation and the color quenching of the generated photon to photomultiplier tubes (PMT) were determined their effects not only to decrease the analytical efficiency but also to change the optimal PSA level and background due to high ion contents of groundwaters. The optimal PSA level was shown in the range of 90 to 110 with less than 5% error. The effects of high ion contents in groundwater for the analytical efficiency show within 10% error from the different ion contents. The chloroform as a quenching agent was used to determine the analytical efficiency with the different amount, showing that the efficiency decreases 20% using the 2% of chloroform.

• Proceedings of the Korean Nuclear Society Conference
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• 1997.05a
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• pp.611-616
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• 1997

The Level 1 probabilistic safety assessment(PSA) for Wolsong(WS) 2/3/4 nuclear power plant(NPPs) in design stage is performed using the methodologies being equivalent to PWR PSA. Accident sequence evaluation program(ASEP) human reliability analysis(HRA) procedure and technique for human error rate prediction(THERP) are used in HRA of WS 2/3/4 NPPs PSA. The purpose of this paper is to introduce the procedure and methodology of HRA in WS 2/3/4 NPPs PSA. Also, this paper describes the interim results of importance analysis for human actions modeled in WS 2/3/4 PSA and the findings and recommendations of administrative control of secondary control area from the view of human factors.

• Journal of the Korean Society of Safety
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• v.36 no.2
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• pp.101-110
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• 2021

This paper presents the results of an initiating event analysis as part of a Level 1 probabilistic safety assessment (PSA) for at-power internal events for the Korea Research Reactor (KRR). The PSA methodology is widely used to quantitatively assess the safety of research reactors (RRs) in the domestic nuclear industry. Initiating event frequencies are required to conduct a PSA, and they considerably affect the PSA results. Because there is no domestic database for domestic trip events, the safety of RRs is usually assessed using foreign databases. In this paper, operating experience data from the KRR for trip events were collected and analyzed in order to determine the frequency of specific initiating events. These frequencies were calculated using two approaches according to the event characteristics and data availability: (1) based on KRR operating experience or (2) using generic data.

• Journal of Korean Biological Nursing Science
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• v.22 no.2
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• pp.71-80
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• 2020

Purpose: The purpose of this study was to review primary research exploring the correlations between the levels of serum testosterone and the prostate-specific antigen (PSA) in healthy men without prostate diseases. Methods: An integrative review was conducted using the Whittemore & Knafle (2005) framework. The keywords, 'testosterone & prostate-specific antigen', 'testosterone & PSA' and 'healthy men' were used to search peer-reviewed publications in six databases. Among 1,959 searched articles, eleven articles were selected after excluding articles that do not meet inclusion criteria. Literature quality was moderate (Level 3). Results: As a result of this study, it was confirmed through the nine articles that healthy adult men showed no significant correlation between the serum testosterone and the PSA. Conversely, two articles presented that the serum PSA correlate positively with the testosterone. In particular, it is inferred that the effect of the serum testosterone and the PSA secreted into a 24-hour circadian rhythm with different amplitudes and slopes would have had great influence. However, it does not consider the factors affecting the testosterone and the PSA, such as race, liver disease, and BMI, so there is insufficient empirical data to clearly explain the relationship between the testosterone and the PSA. Conclusion: The correlation between the serum testosterone and the PSA in healthy adult men is insignificant in relation to the circadian rhythm of the testosterone and the PSA secretion. It is that a large-scale study including various influencing factors using new biochemical indicators such as pro PSA be conducted in the future.

• Asian Pacific Journal of Cancer Prevention
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• v.15 no.15
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• pp.6121-6125
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• 2014

Background: Prostate-specific antigen (PSA) is a potential biomarker for early detection of prostate cancer (PCa) but its level is known to be affected by many background factors and roles of ubiquitous toxicants have not been determined. Endocrine disrupting chemicals (EDCs) are ubiquitous reproductive toxicants used in consumer products, which promote tumor formation in some reproductive model systems by binding to AhR, but human data on its expression in prostate cancer as well as its association with PSA levels are not clear. This study aimed to evaluate the expression levels of AhR and its association with serological levels of PSA and to detect possible effects of background factors and EDC exposure history on PSA levels in PCa cases. Materials and Methods: A cross-sectional study was conducted on the tissue levels of AhR and serum levels of PSA in 53 PCa cases from 2008-2011 and associations between each and background and lifestyle related factors were determined. Results: Although the AhR was overexpressed in PCa and correlated with the age of patients, it did not correlate with PSA levels.Of nutritional factors, increased intake of polysaturated fats and fish in the routine regimen of PCa cases increased the PSA levels significantly. Conclusions: AhR overexpression in PCa pontws to roles of EDCs in PCa but without any direct association with PSA levels. However, PSA levels are affected by exposure to possible toxicants in foods whichneed to be assessed as possible risk factors of PCa in future studies.

• Nuclear Engineering and Technology
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• v.52 no.10
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• pp.2221-2229
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• 2020

After the Fukushima Daiichi nuclear power plant (NPP) accident, level 3 probabilistic safety assessment (PSA) has emerged as an important task in order to assess the risk level of the multi-unit NPPs in a single nuclear site. Accurate calculation of the radionuclide concentrations and exposure doses to the public is required if a nuclear site has multi-unit NPPs and large number of people live near NPPs. So, there has been a great need to develop a new method or procedure for the fast and accurate offsite consequence calculation for the multi-unit NPP accident analysis. Since the multi-unit level 3 PSA is being currently performed assuming that all the NPPs are located at the same position such as a center of mass (COM) or base NPP position, radionuclide concentrations or exposure doses near NPPs can be drastically distorted depending on the locations, multi-unit NPP alignment, and the wind direction. In order to overcome this disadvantage of the COM method, the idea of a new multiple location (ML) method was proposed and implemented into a new tool MURCC (multi-unit radiological consequence calculator). Furthermore, the MURCC code was further improved for the multi-unit level 3 PSA that has the arbitrary number of multi-unit NPPs. The objectives of this study are to (1) qualitatively and quantitatively compare COM and ML methods, and (2) demonstrate the strength and efficiency of the ML method. The strength of the ML method was demonstrated by the applications to the multi-unit long-term station blackout (LTSBO) accidents at the four-unit Vogtle NPPs. Thus, it is strongly recommended that this ML method be employed for the offsite consequence analysis of the multi-unit NPP accidents.