• Title/Summary/Keyword: PSA level

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A Study on the Optimization of Offsite Consequence Analysis by Plume Segmentation and Multi-Threading (플룸분할 및 멀티스레딩을 통한 소외사고영향 분석시간 최적화 연구)

  • Seunghwan, Kim;Sung-yeop, Kim
    • Journal of the Korean Society of Safety
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    • v.37 no.6
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    • pp.166-173
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    • 2022
  • A variety of input parameters are taken into consideration while performing a Level 3 PSA. Some parameters related to plume segments, spatial grids, and particle size distribution have flexible input formats. Fine modeling performed by splitting a number of segments or grids may enhance the accuracy of analysis but is time-consuming. Analysis speed is highly important because a considerably large number of calculations is required to handle Level 2 PSA scenarios for a single-unit or multi-unit Level 3 PSA. This study developed a sensitivity analysis supporting interface called MACCSsense to compare the results of the trials of plume segmentation with the results of the base case to determine its impact (in terms of time and accuracy) and to support the development of a modeling approach, which saves calculation time and improves accuracy. MACCSense is an automation tool that uses a large amount of plume segmentation analysis results obtained from MUST Converter and Mr. Manager developed by KAERI to generate a sensitivity report that includes impact (time and accuracy) by comparing them with the base-case result. In this study, various plume segmentation approaches were investigated, and both the accuracy and speed of offsite consequence analysis were evaluated using MACCS as a consequence analysis tool. A simultaneous evaluation revealed that execution time can be reduced using multi-threading. In addition, this study can serve as a framework for the development of a modeling strategy for plume segmentation in order to perform accurate and fast offsite consequence analyses.

Study on the Code System for the Off-Site Consequences Assessment of Severe Nuclear Accident (원전 중대사고 연계 소외결말해석 전산체계에 대한 고찰)

  • Kim, Sora;Min, Byung-Il;Park, Kihyun;Yang, Byung-Mo;Suh, Kyung-Suk
    • Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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    • v.14 no.4
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    • pp.423-434
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    • 2016
  • The importance of severe nuclear accidents and probabilistic safety assessment (PSA) were brought to international attention with the occurrence of severe nuclear accidents caused by the extreme natural disaster at Fukushima Daiichi nuclear power plant in Japan. In Korea, studies on level 3 PSA had made little progress until recently. The code systems of level 3 PSA, MACCS2 (MELCORE Accident Consequence Code System 2, US), COSYMA (COde SYstem from MAria, EU) and OSCAAR (Off-Site Consequence Analysis code for Atmospheric Releases in reactor accidents, JAPAN), were reviewed in this study, and the disadvantages and limitations of MACCS2 were also analyzed. Experts from Korea and abroad pointed out that the limitations of MACCS2 include the following: MACCS2 cannot simulate multi-unit accidents/release from spent fuel pools, and its atmospheric dispersion is based on a simple Gaussian plume model. Some of these limitations have been improved in the updated versions of MACCS2. The absence of a marine and aquatic dispersion model and the limited simulating range of food-chain and economic models are also important aspects that need to be improved. This paper is expected to be utilized as basic research material for developing a Korean code system for assessing off-site consequences of severe nuclear accidents.

A case report of monitoring PSA level changes in two prostate cancer patients treated with Mountain Ginseng Pharmacopuncture and Sweet Bee Venom along with western anticancer therapy (양방 항암치료와 병행하여 산삼약침과 봉약침 치료를 받은 전립선암 환자들의 PSA 수치 변화 관찰 보고)

  • Lee, Yeon-Hee;Kim, Chae-Won;Lee, Kwang-Ho
    • Journal of Pharmacopuncture
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    • v.14 no.4
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    • pp.81-88
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    • 2011
  • Objectives: The purpose of this report is to find out how Mountain Ginseng Pharmacopuncture(MGP) and Sweet Bee Venom(SBV) treatments are effective on prostate cancer patients by monitoring Prostate specific antigen(PSA) values. Methods: We treated two prostate cancer patients with MGP and SBV from October 2008 to April 2011. One patient had localized prostate cancer, the other was in the terminal stage of prostate cancer with lung and bone metastasis and both had been receiving western anticancer therapy. We had monitored the changes of PSA value. Results: In case 1, MGP and SBV treatments seemed to be helpful in preventing the recurrence of localized prostate cancer. In case 2, PSA value was decreased by MGP treatment. Conclusions: It is conceivable that MGP and SBV are effective treatments for patients with prostate cancer.

A new methodology for modeling explicit seismic common cause failures for seismic multi-unit probabilistic safety assessment

  • Jung, Woo Sik;Hwang, Kevin;Park, Seong Kyu
    • Nuclear Engineering and Technology
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    • v.52 no.10
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    • pp.2238-2249
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    • 2020
  • In a seismic PSA, dependency among seismic failures of components has not been explicitly modeled in the fault tree or event tree. This dependency is separately identified and assigned with numbers that range from zero to unity that reflect the level of the mutual correlation among seismic failures. Because of complexity and difficulty in calculating combination probabilities of correlated seismic failures in complex seismic event tree and fault tree, there has been a great need of development to explicitly model seismic correlation in terms of seismic common cause failures (CCFs). If seismic correlations are converted into seismic CCFs, it is possible to calculate an accurate value of a top event probability or frequency of a complex seismic fault tree by using the same procedure as for internal, fire, and flooding PSA. This study first proposes a methodology to explicitly model seismic dependency by converting correlated seismic failures into seismic CCFs. As a result, this methodology will allow systems analysts to quantify seismic risk as what they have done with the CCF method in internal, fire, and flooding PSA.

Diabetes Mellitus and HbA1c Levels Associated with High Grade Prostate Cancer

  • Ozbek, Emin;Otunctemur, Alper;Dursun, Murat;Sahin, Suleyman;Besiroglu, Huseyin;Koklu, Ismail;Erkoc, Mustafa;Danis, Eyyup;Bozkurt, Muammer
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.6
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    • pp.2555-2558
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    • 2014
  • Pirpose: The aim of this study to analyze the association between history of diabetes mellitus (DM) with risk of prostate cancer (PCa) and cancer grade among men undergoing radical prostatectomy for PCa. Materials and Methods: 50 patients with DM and 50 patients without DM who undervent radical prostatectomy (RP) were included in the study. Age at biopsy, height, weight, digital rectal examination (DRE), pre-biopsy PSA levels, prostate volume, histopathologic diagnosis after surgery and gleason scores were collected data from all patients. Histologic material obtained at biopsy was given a Gleason score; tumours with a Gleason score ${\geq}7$ were considered high grade and <7 were considered low grade. Results: The mean age at the time of biopsy was 63.7 in patients with DM and 61.6 in patients without DM. Diabetic men had significantly lower PSA levels (p=0.01). Mean PSA level $7.04{\pm}2.85$ in patients with DM and $8.7{\pm}2.86$ in patients without DM, respectively. Also, diabetic men had higher RP tumor grade than men without DM (p=0.04). We found that HbA1c levels were higher in patients who have high grade prostate cancer (p<0.05). Conclusions: Diabetic men undergoing RP have lower PSA levels and have significantly higher grade PCa. We must be careful for screening PCa in patients with DM. Although the patients had lower PSA levels, they might have high grade disease.

Prostate Biomarkers with Reference to Body Mass Index and Duration of Prostate Cancer

  • Poudel, Bibek;Mittal, Ankush;Shrestha, Rojeet;Nepal, Ashwini Kumar;Shukla, Pramod Shanker
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.5
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    • pp.2149-2152
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    • 2012
  • Objective: This study was performed to assess prostate biomarkers with reference to body mass index and duration of prostate cancer. Materials and Methods: A hospital based retrospective study was undertaken using data retrieved from the register maintained in the Department of Biochemistry of Manipal Teaching Hospital, Pokhara, Nepal between $1^{st}$ January, 2009 and $28^{th}$ February, 2012. Biomarkers studied were prostate specific antigen (PSA), acid phosphatase (ACP) and prostatic acid phosphatase (PAP), alkaline phosphatase (ALP) and gamma glutamyl transpeptidase (${\gamma}GT$). Demographic data including age, duration of disease, body weight, height and body mass index (BMI) were also collected. Duration of disease was categorized into three groups: <1 year, 1-2years and >2 years. Similarly, BMI ($kg/m^2$) was categorized into three groups: <23 $kg/m^2$, 23-25 $kg/m^2$ and >25 $kg/m^2$. Descriptive statistics and testing of hypothesis were used for the analysis using EPI INFO and SPSS 16 software. Results: Out of 57 prostate cancers, serum level of PSA, ACP and PAP were increased above the cut-off point in 50 (87.5%), 30 (52.63%) and 40 (70.18%) respectively. Serum levels of PSA, ACP and PAP significantly declined with the duration of disease after diagnosis. We observed significant and inverse relation between PSA and BMI. Similar non-signficiant tendencies were apparent for ACP and PAP. Conclusions: Decreasing levels of prostate biomarkers were found with the duration of prostate cancer and with increased BMI. Out of prostate biomarkers, PSA was found to be significantly decreased with the duration of disease and BMI.

Vital Area Identification for the Physical Protection of Nuclear Power Plants during Low Power and Shutdown Operation (원자력발전소 정지저출력 운전 기간의 물리적방호를 위한 핵심구역파악)

  • Kwak, Myung Woong;Jung, Woo Sik;Lee, Jeong-ho;Baek, Min
    • Journal of the Korean Society of Safety
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    • v.35 no.1
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    • pp.107-115
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    • 2020
  • This paper introduces the first vital area identification (VAI) process for the physical protection of nuclear power plants (NPPs) during low power and shutdown (LPSD) operation. This LPSD VAI is based on the 3rd generation VAI method which very efficiently utilizes probabilistic safety assessment (PSA) event trees (ETs). This LPSD VAI process was implemented to the virtual NPP during LPSD operation in this study. Korea Atomic Energy Research Institute (KAERI) had developed the 2nd generation full power VAI method that utilizes whole internal and external (fire and flooding) PSA results of NPPs during full power operation. In order to minimize the huge burden of the 2nd generation full power VAI method, the 3rd generation full power VAI method was developed, which utilizes ETs and minimal PSA fault trees instead of using the whole PSA fault tree. In the 3rd generation full power VAI method, (1) PSA ETs are analyzed, (2) minimal mitigation systems for avoiding core damage are selected from ETs by calculating system-level target sets and prevention sets, (3) relatively small sabotage fault tree that has the systems in the shortest system-level prevention set is composed, (4) room-level target sets and prevention sets are calculated from this small sabotage fault tree, and (5) the rooms in the shortest prevention set are defined as vital areas that should be protected. Currently, the 3rd generation full power VAI method is being employed for the VAI of Korean NPPs. This study is the first development and application of the 3rd generation VAI method to the LPSD VAI of NPP. For the LPSD VAI, (1) many LPSD ETs are classified into a few representative LPSD ETs based on the functional similarity of accident scenarios, (2) a few representative LPSD ETs are simplified with some VAI rules, and then (3) the 3rd generation VAI is performed as mentioned in the previous paragraph. It is well known that the shortest room-level prevention sets that are calculated by the 2nd and 3rd generation VAI methods are identical.

The Effects of Isoflavone Supplementation on Serum PSA, Lipid Profile, Antioxidant and Immune System in Prostate Cancer Patients (이소플라본 섭취가 전립선암환자의 Serum PSA, 지질패턴, 항산화체계 및 면역체계에 미치는 영향)

  • Lee, Joo-Min;Hong, Sung-Joon;Lee, Min-June;Yoon, Sun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.33 no.8
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    • pp.1294-1301
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    • 2004
  • Soy foods are a unique dietary source of isoflavones, which have effects relevant to prostate cancer prevention. The present study determines the effects of a short-term isoflavone supplement on serum PSA (prostate specific antigen), lipid profile, antioxidant status, and immune system in prostate cancer patients. Ten prostate cancer patients were supplemented daily with 150 mg of isoflavone for 2 months. Blood samples were collected baseline and 2 month after for analysis of PSA, serum lipid profiles, total antioxidant status (TAS), grade of DNA damage in lymphocytes, IL-6, VEGF and TNF -$\alpha$. After 2 month isoflavone supplementation, increased significantly a total of estimated urinary isoflavone excretion and did not change PSA. Serum lipid profiles showed significant change in serum total cholesterol level (p=0.007). However, there was no significant change in HDL- and LDL-cholesterol levels. TAS was increased but not significant after isoflavone supplementation. Tail moment (TM) was decreased and especially tail length (TL) was decreased significantly (p=0.043). IL-6 level was decreased but VEGF level and TNF -$\alpha$ level were increased. The results of the present study led to the conclusion that the isoflavone dosage (150 mg) in supplement had positive effects on the serum total cholesterol level and DNA damage.