• 제목/요약/키워드: Hazard risk

검색결과 1,650건 처리시간 0.026초

BTX 공정에서 Gas Detector Mapping 적정성 검토에 관한 연구 (A Study on Validation for Mapping of Gas Detectors at a BTX Plant)

  • 서지혜;한만형;김일권;천영우
    • 한국안전학회지
    • /
    • 제32권5호
    • /
    • pp.168-178
    • /
    • 2017
  • In order to prevent major and chemical accidents, some of the plants which would like to install and operate hazard chemicals handling facilities must submit Off-site Consequence Analysis due to recent arisen leak accidents since 2015. A lot of chemical industrials choose gas detectors as mitigation equipment to early detect gas vapor. The way of placement of gas detectors has two methods; Code-based Design(CBD) and Performance-based Design. The CBD has principles for gas detectors to be installed with consideration for the place that is expected to accumulate gas, and the leak locations according to legal standards and technical guidelines, and has a possibility to be unable to detect by these rules to locate gas detectors by vapor density information. The PBD has two methods; a Geographic Method and Scenario based Method. The Scenario-based Method has been suggested to make up for the Geographic Coverage Method. This Scenario-based Method draw the best optimum placement of gas detectors by considering leak locations, leak speed information, leak directions and etc. However, the domestic placement guidelines just refers to the CBD. Therefore, this study is to compare existing placement location of gas detectors by the domestic CBD with placement locations, coverages and the number of gas detectors in accordance with the Scenario-based Method. Also this study has measures for early detecting interest of Vapor Cloud and suitable placement of gas detectors to prevent chemical accidents. The Phast software was selected to simulate vapor cloud dispersion to predict the consequence. There are two cases; an accident hole size of leak(8 mm) from API which is the highst accident hole size less than 24.5 mm, and a normal leak hole size from KOSHA Guide (1.8 mm). Detect3D was also selected to locate gas detectors efficiently and compare CBD results and PBD results. Currently, domestic methods of gas detectors do not consider any risk, but just depend on domestic code methods which lead to placement of gas detectors not to make personnels recognize tolerable or intolerable risks. The results of the Scenario-based Method, however, analyze the leak estimated range by simulating leak dispersion, and then it is able to tell tolerable risks. Thus it is considered that individuals will be able to place gas detectors reasonably by making objectives and roles flexibly according to situations in a specific plant.

Association between Lymphovascular Invasion and Recurrence in Patients with pT1N+ or pT2-3N0 Gastric Cancer: a Multi-institutional Dataset Analysis

  • Fujita, Keizo;Kanda, Mitsuro;Ito, Seiji;Mochizuki, Yoshinari;Teramoto, Hitoshi;Ishigure, Kiyoshi;Murai, Toshifumi;Asada, Takahiro;Ishiyama, Akiharu;Matsushita, Hidenobu;Tanaka, Chie;Kobayashi, Daisuke;Fujiwara, Michitaka;Murotani, Kenta;Kodera, Yasuhiro
    • Journal of Gastric Cancer
    • /
    • 제20권1호
    • /
    • pp.41-49
    • /
    • 2020
  • Purpose: Patients with pathological stage T1N+ or T2-3N0 gastric cancer may experience disease recurrence following curative gastrectomy. However, the current Japanese Gastric Cancer Treatment Guidelines do not recommend postoperative adjuvant chemotherapy for such patients. This study aimed to identify the prognostic factors for patients with pT1N+ or pT2-3N0 gastric cancer using a multi-institutional dataset. Materials and Methods: We retrospectively analyzed the data obtained from 401 patients with pT1N+ or pT2-3N0 gastric cancer who underwent curative gastrectomy at 9 institutions between 2010 and 2014. Results: Of the 401 patients assessed, 24 (6.0%) experienced postoperative disease recurrence. Multivariate analysis revealed that age ≥70 years (hazard ratio [HR], 2.62; 95% confidence interval [CI], 1.09-7.23; P=0.030) and lymphatic and/or venous invasion (lymphovascular invasion (LVI): HR, 7.88; 95% CI, 1.66-140.9; P=0.005) were independent prognostic factors for poor recurrence-free survival. There was no significant association between LVI and the site of initial recurrence. Conclusions: LVI is an indicator of poor prognosis in patients with pT1N+ or pT2-3N0 gastric cancer.

P53 and MDM2 Over-expression and Five-year Survival of Kidney Cancer Patients Undergoing Radical Nephrectomy - Iranian Experience

  • Abolhasani, Maryam;Salarinejad, Sareh;Asgari, Mojgan
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제16권12호
    • /
    • pp.5043-5047
    • /
    • 2015
  • Background: Relatively little is known with certainty about the status and role of p53 or MDM2 in predicting prognosis and survival of renal cell carcinoma. The present study aimed to determine the value of P53 and MDM2 over-expression, alone and simultaneously, to predict five-year survival of patients with kidney cancer in Iran. Materials and Methods: Patients with kidney cancer referred to Hasheminejad Kidney Center between 2007 and 2009, underwent radical nephrectomy and had pathology reports of clear cell, papillary or chromophobe renal cell carcinoma were included in our cohort study. Other histological types of renal cell carcinoma were not included. The patients with missed, incomplete or poor quality paraffin blocks were also excluded. Overall ninety one patients met the inclusion and exclusion criteria. To assess the histopathological features of the tumor, immunohistochemical (IHC) staining of formalin fixed, paraffin-embedded tumor samples were performed. The five-year survival was determined by the patients' medical files and telephone following-up. Results: In total, 1.1% of all samples were revealed to be positive for P53. Also, 20.8% of all samples were revealed to be positive for MDM2.The patients were all followed for 5 years. In this regard, 5-year mortality was 30.5% and thus 5-year survival was 85.3%. According to the Cox proportional hazard analysis, positive P53 marker was only predictor for patients' 5-year survival that the presence of positive p53 increased the risk for long-term mortality up to 2.8 times (HR=2.798, 95%CI: 1.176-6.660, P=0.020). However, the presence of MDM2 could not predict long-term mortality. In this regard, analysis by the ROC curve showed a limited role for predicting long-term survival by confirming P53 positivity (AUC=0.610, 95%CI: 0.471-.750, P=0.106). The best cutoff point for P53 to predict mortality was 0.5 yielding a low sensitivity (32.0%) but a high specificity (97.9%). In similar analysis, measurement of MDM2 positivity could not predict mortality (AUC=0.449, 95%CI: 0.316-.583, P=0.455). Conclusions: The simultaneous presence of both P53 and MDM2 markers in our population is a rare phenomenon and the presence of these markers may not predict long-term survival in patients who undergoing radical nephrectomy.

Comparison of the Efficacy and Safety of EFGR Tyrosine Kinase Inhibitor Monotherapy with Standard Second-line Chemotherapy in Previously Treated Advanced Non-small-cell Lung Cancer: a Systematic Review and Meta-analysis

  • Qi, Wei-Xiang;Shen, Zan;Lin, Feng;Sun, Yuan-Jue;Min, Da-Liu;Tang, Li-Na;He, Ai-Na;Yao, Yang
    • Asian Pacific Journal of Cancer Prevention
    • /
    • 제13권10호
    • /
    • pp.5177-5182
    • /
    • 2012
  • Purpose: To compare the efficacy and safety of epidermal growth factor receptor tyrosine kinase inhibitormonotherapy (EFGR-TKIs: gefitinib or erlotinib) with standard second-line chemotherapy (single agent docetaxel or pemetrexed) in previously treated advanced non-small-cell lung cancer (NSCLC). Methods: We systematically searched for randomized clinical trials that compared EGFR-TKI monotherapy with standard second-line chemotherapy in previously treated advanced NSCLC. The end points were overall survival (OS), progression-free survival (PFS), overall response rate (ORR), 1-year survival rate (1-year SR) and grade 3 or 4 toxicities. The pooled hazard ratio (HR) or risk ratio (RR), with their corresponding 95% confidence intervals (CI) were calculated employing fixed- or random-effects models depending on the heterogeneity of the included trials. Results: Eight randomized controlled trials (totally 3218 patients) were eligible. Our meta-analysis results showed that EGFR-TKIs were comparable to standard second-line chemotherapy for advanced NSCLC in terms of overall survival (HR 1.00, 95%CI 0.92-1.10; p=0.943), progression-free survival (HR 0.90, 95%CI 0.75-1.08, P=0.258) and 1-year-survival rate (RR 0.97, 95%CI 0.87-1.08, P=0.619), and the overall response rate was higher in patients who receiving EGFR-TKIs(RR 1.50, 95%CI 1.22-1.83, P=0.000). Sub-group analysis demonstrated that EGFR-TKI monotherapy significantly improved PFS (HR 0.73, 95%CI: 0.55-0.97, p=0.03) and ORR (RR 1.96, 95%CI: 1.46-2.63, p=0.000) in East Asian patients, but it did not translate into increase in OS and 1-year SR. Furthermore, there were fewer incidences of grade 3 or 4 neutropenia, febrile neutropenia and neutrotoxicity in EGFR-TKI monotherapy group, excluding grade 3 or 4 rash. Conclusion: Both interventions had comparable efficacy as second-line treatments for patients with advanced NSCLC, and EGFR-TKI monotherapy was associated with less toxicity and better tolerability. Moreover, our data also demonstrated that EGFR-TKImonotherapy tended to be more effective in East Asian patients in terms of PFS and ORR compared with standard second-line chemotherapy. These results should help inform decisions about patient management and design of future trials.

탄화수소계 올리고머를 이용한 환경친화적 고무계면 접착제 개발 (Development of Environmental Rubber Interphase Adhesive by use of Oligomer of Hydrocarbon)

  • 장병만;장정석;박성수;최덕제;김수경
    • 폴리머
    • /
    • 제25권1호
    • /
    • pp.142-150
    • /
    • 2001
  • 그 동안 고무산업 현장에서는 유기용제계 고무 접착제를 사용하여 왔으며 이로인해 품질의 불균일성과 화재위험성 및 인체유해성이 상존하여 왔다. 이를 해결하기 위해 비휘발성, 고인화점인 탄화수소계 원료를 사용하여 새로운 용액을 개발하였으며 이 용액은 인체에 대한 유해성이 매우 적으며 증발이 되지 않으므로 화재위험 및 환경적인 문제를 해결할 수 있었다. 새로운 용액은 기존 제품에 사용되어 온 고무계 binder대신 고무면으로 비휘발성 용제가 침투, 팽윤 현상을 일으켜 고무면 끼리 접착을 유도하는 새로운 개념의 제품이며 접착력 유지 시간이 기존 제품에 비해 현저히 개선되었다. 또한 내구력 면에서도 기존품과 비교할 때 유사한 양상을 보이므로 팽윤 현상으로 인한 물성저하가 나타나지 않았으며 각종 첨가제와도 반응성이 없는 안정한 제품이었다. 기존품의 경우 가교 후 절단면에서 가스로 인한 균열이 발생한 반면 새로운 제품의 경우는 이러한 현상이 발생하지 않았다.

  • PDF

재난 강도에 따른 도로 네트워크의 성능 및 회복력 산정 방안 (Estimation of Road-Network Performance and Resilience According to the Strength of a Disaster)

  • 정호용;최승현;도명식
    • 한국도로학회논문집
    • /
    • 제20권1호
    • /
    • pp.35-45
    • /
    • 2018
  • PURPOSES : This study examines the performance changes of road networks according to the strength of a disaster, and proposes a method for estimating the quantitative resilience according to the road-network performance changes and damage scale. This study also selected high-influence road sections, according to disasters targeting the road network, and aimed to analyze their hazard resilience from the network aspect through a scenario analysis of the damage recovery after a disaster occurred. METHODS : The analysis was conducted targeting Sejong City in South Korea. The disaster situation was set up using the TransCAD and VISSIM traffic-simulation software. First, the study analyzed how road-network damage changed the user's travel pattern and travel time, and how it affected the complete network. Secondly, the functional aspects of the road networks were analyzed using quantitative resilience. Finally, based on the road-network performance change and resilience, priority-management road sections were selected. RESULTS : According to the analysis results, when a road section has relatively low connectivity and low traffic, its effect on the complete network is insignificant. Moreover, certain road sections with relatively high importance can suffer a performance loss from major damage, for e.g., sections where bridges, tunnels, or underground roads are located, roads where no bypasses exist or they exist far from the concerned road, including entrances and exits to suburban areas. Relatively important roads have the potential to significantly degrade the network performance when a disaster occurs. Because of the high risk of delays or isolation, they may lead to secondary damage. Thus, it is necessary to manage the roads to maintain their performance. CONCLUSIONS : As a baseline study to establish measures for traffic prevention, this study considered the performance of a road network, selected high-influence road sections within the road network, and analyzed the quantitative resilience of the road network according to scenarios. The road users' passage-pattern changes were analyzed through simulation analysis using the User Equilibrium model. Based on the analysis results, the resilience in each scenario was examined and compared. Sections where a road's performance loss had a significant influence on the network were targeted. The study results were judged to become basic research data for establishing response plans to restore the original functions and performance of the destroyed and damage road networks, and for selecting maintenance priorities.

Prognostic value of neutrophil-to-lymphocyte ratio in locally advanced non-small cell lung cancer treated with concurrent chemoradiotherapy

  • Park, Eun Young;Kim, Yeon-Sil;Choi, Kyu Hye;Song, Jin Ho;Lee, Hyo Chun;Hong, Sook-Hee;Kang, Jin-Hyoung
    • Radiation Oncology Journal
    • /
    • 제37권3호
    • /
    • pp.166-175
    • /
    • 2019
  • Purpose: This study aimed to investigate neutrophil-to-lymphocyte ratio (NLR) and platelet-to-lymphocyte ratio (PLR) as prognostic factors in patients with locally advanced non-small cell lung cancer (NSCLC) who received concurrent chemoradiotherapy (CCRT). Materials and Methods: We retrospectively analyzed 66 patients with locally advanced NSCLC treated with definitive CCRT. Among these patients, 95% received paclitaxel/carboplatin or docetaxel/cisplatin. The median radiation dose was 66 Gy in 33 fractions. The NLR and PLR before/after CCRT were evaluated. The maximally selected log-rank test was used to obtain the cutoff values related to the overall survival (OS). Results: Patients with high post-CCRT NLR (>3.12) showed worse OS, locoregional progression-free survival (LRPFS), and distant metastasis-free survival (DMFS) than those with low NLR (2-year OS: 25.8% vs. 68.2%, p < 0.001; 2-year LRPFS: 12.9% vs. 33.8%, p = 0.010; 2-year DMFS: 22.6% vs. 38.2%, p = 0.030). Patients with high post-CCRT PLR (>141) showed worse OS and LRPFS than those with low PLR (2-year OS: 37.5% vs. 71.1%, p = 0.004; 2-year LRPFS: 16.5% vs. 40.3%, p = 0.040). Patients with high NLR change (>1.61) showed worse OS and LRPFS than those with low NLR change (2-year OS: 26.0% vs. 59.0%, p < 0.001; 2-year LRPFS: 6.8% vs. 31.8%, p = 0.004). The planning target volume (hazard ration [HR] = 2.05, p = 0.028) and NLR change (HR = 3.17, p = 0.025) were the significant factors for OS in the multivariate analysis. Conclusion: NLR change after CCRT was associated with poor prognosis of survival in patients with locally advanced NSCLC. An elevated NLR after CCRT might be an indicator of an increased treatment failure risk.

유통중인 생선초밥의 오염 미생물 분석 (Microbial Contamination Analysis to Assess the Safety of Marketplace Sushi)

  • 조선경;문보연;박종현
    • 한국식품과학회지
    • /
    • 제41권3호
    • /
    • pp.334-338
    • /
    • 2009
  • 어패류에 의한 식중독 발생 감소를 위하여 시장에서 유통중인 생선초밥을 대형할인매장과 일식음식점에서 수집하여 미생물 위해인자의 오염을 분석하였다. 79개의 초밥의 생선부위에서 4-6 log CFU/g의 일반세균이 오염되어 있었고 밥부위에서는 3-5 log CFU/g 로 나왔으며 광어와 새우초밥이 높은 오염을 보여주었다. 대장균군은 생선부위에서 3-4 log CFU/g이 오염되어 있었고 밥부위에는 생선부위보다 1 log CFU/g정도 낮게 나타났고 대장균은 검출되지 않았다. 식중독 세균은 생선부위에서 Staphylococcus aureus가 17% 시료에서 검출되었고, Bacillus cereus group은 10%로 검출되었고 밥부위에서는 S. aureus가 11%시료에서 검출되었고 B. cereus group가 8% 시료에서 검출되었다. 그리고 Salmonella와 Listeria monocytogenes도 검출되었으나 Vibrio parahaemolyticus, Clostridium perfrigens, Yersinia enterpcolotica 등은 검출되지 않았다. 생선초밥 생산유통 업체 분석에 의하면 대형할인매장의 시료에서는 B. cereus group이 13%시료에서 검출되었고, 일식음식점의 경우는 S. aureus가 30% 시료에서 검출되었다. 일반적으로 어패류 식품의 경우 V. parahaemolyticus의 오염을 우려하지만, 유통 초밥시료를 채취하여 실험한 결과 B. cereus group과 S. aureus의 오염도가 더욱 높은 것으로 나타났다. 그러므로 V. parahaemolyticus와 아울러 B. cereus group과 S. aureus의 위해 관리가 강화되어야 할 것으로 사료된다.

등속공급 튜브연소로를 이용한 각 연소조건에서의 연기입자 형상 분석 (Studies on the Morphology of Smoke Particles for Each Type of Fire by Using Steady State Tube Furnace)

  • 구재학
    • 한국화재소방학회논문지
    • /
    • 제28권1호
    • /
    • pp.44-51
    • /
    • 2014
  • 화재현장에서 발생하는 연기는 일반적으로 연소가스와 더불어 여러 가지 성분의 유기증기 및 미연탄소로부터 생성된 미세입자로 되어 있다. 연기는 호흡기로 흡입되어 장단기 인체피해를 유발한다. 화재 시 발생하는 유독가스나 입자에 의한 피해를 예측하기 위해서는 연기입자의 호흡기관 내 이송과 침전, 그리고 입자를 매개로 한 유독가스의 흡수와 흡착등의 현상 파악이 필수적이며 이에 연기입자의 크기 및 형상은 이와 같은 현상의 변화에 중요한 변수로서 작용한다. 이 연구에서는 화재 시 발생하는 연기입자의 흡입에 의한 인체피해 특성을 예측하기 위하여 가연물 및 화재 조건에 따른 연기입자의 크기 및 형상에 대한 분석을 수행하였다. 국제표준에 따른 연소생성물 분석을 위하여 ISO/TS 19700 기준에 따라서 등속연소로를 제작하고 각 가연물에 대하여 연소로 온도 및 당량비 조건으로 정해지는 4가지 대표적인 화재조건, 즉, 저온불완전연소, 완전불꽃연소, 불완전불꽃연소, 고온불완전연소 조건에서 연기입자를 발생시켰다. 발생된 연기입자는 다단 충돌집진기를 이용하여 채집한 다음 투과전자현미경으로 크기 및 형상을 분석하였다.

다중회귀분석을 통한 경남 지방도로 절취사면의 안정성평가 (Risk Assessment of the Road Cut Slopes in Gyeoungnam based on Multiple Regression Analysis)

  • 강태승;엄정기
    • 지질공학
    • /
    • 제17권3호
    • /
    • pp.393-404
    • /
    • 2007
  • 본 연구는 절리암반사면의 현장상태 및 위험도에 대한 현장조사를 기초로 사면의 상대적 위험도를 판단 할 수 있는 토대를 마련하기 위하여 개별요인이 사면안정성에 미치는 영향을 고찰하였으며 사면붕괴에 영향을 미치는 요인들에 대한 통계적 분석을 수행하였다. 사면의 붕괴요인으로는 기존에 제시된 인장균열, 지반변형, 구조물 변형, 붕괴발생규모, 절리주향, 절리경사, 절리상태, 사면경사, 강우 및 지하수위, 절취상태, 배수조건, 보호보강상태 등 12가지 항목을 고려하였다. 본 연구를 위한 조사지역은 경상남도 지방도로에 위치한 절취사면 중 붕괴 이력이 있거나 다소 불안감을 보이는 위험 절개지 233개소이다. 조사지역의 사면안정성평가는 각각의 평가요인(붕괴요인)에 따른 사면의 결함지수와 사면위험등급에 의해 수행되었다. 조사된 총 233개소의 사면 중 토사사면을 제외한 암반사면 126개소를 선별하여, 각각의 붕괴요인들과 사면위험등급과의 통계적 연관성분석을 실시하였다. 또한, 다중회귀분석을 수행하고 적용성을 고찰하여 사면결함지수와 위험등급을 예측할 수 있는 통계모형을 제시하였다.