• Journal of the Korean Institute of Navigation
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• v.18 no.4
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• pp.33-47
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• 1994

On developing port system, the performance tests of system in relation to ship maneuver generally consists of the three parts: the channel transit, the manoeuvring in a turning basin and the docking/undocking. The quantifications of risk of an accident has priviously been difficult due to the low occurrence of accidents relative to the number of transits. Additionally, accident statistics could not be related port system because of the large number of factors contributing to the accident. such as human error, equipment failure, visibility, light, traffic. etc. In case of the channel transit, "Relative Risk Factor(RRF)" or "Relative Risk Factor for Meeting Traffic" was proposed as the as the measures derived to quantify the relative risk of accident by M.W.Smith. This factor measure the tracking performance, the turning performance and the passing performance at meeting traffic. On the other hand, the safety of berthing maneuver is not measured with a few evaluating factors as controlled due to complex controllabilites such as steering, engine, side thrusters or tugs. This work, therefore, aims to propose the evaluating measure by the Analytic Hierarchy Process(AHP). Six experimental scenarios were establised under the various environmental conditions as independent variables. In every simulation, the difficulty of maneuver was scored by captain and compared with AHP scores. The results show almost same and from which the weights of eight evaluating factors could be fixed. Additionally, the limit value of relative factor in berthing safety to six scenarios could be estimated to 0.11.e estimated to 0.11.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.3
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• pp.257-263
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• 2013

The classification of risk factors and the identification of risk acceptance criteria are core works to assess risk levels with high enough confidential level in the field of marine traffic environment. In the previous study work, the twenty kinds of risk factors and its assessment criteria for the domestic marine traffic environment were proposed. In this paper, with these previous studying results, the relative importance of the risk factors were analyzed by questionnaire survey of marine traffic experts using the analytic hierarchy process. The analysis results showed that the relative importance of the visibility restriction is the highest among the twenty kinds of risk factors, and the relative importance of the traffic condition is the highest among the five kinds of risk categories. As results from analysis, it is expected that the approaching method on the relative importance is to be one of basic techniques for the development of risk assessment models in the domestic marine traffic environment.

• Journal of the Korean Society of Marine Environment & Safety
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• v.19 no.4
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• pp.375-381
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• 2013

To assess the risk of marine traffic environments, with high confidential level, the risk factors comprising it should be identified and the risk acceptance criteria should be also provided. Furthermore, the relative importance of each risk factor(the weight of each risk factor on total risk) should be analyzed because the risk is expressed as the sum of risk factors comprising it. The twenty kinds of risk factors and its assessment criteria were suggested for the domestic marine traffic environments by an examination of the existing risk assessment models on the previous studies. The relative importance of each risk factor was also analyzed through the questionnaire using analytic hierarchy process by the marine traffic experts on the same studies. Based on these previous studies, the risk was evaluated at the port of Mokpo and its approaches on this study. The port of Mokpo and its approaches were divided into four sectors for the comparative evaluation, the result of the comparative evaluation on four sectors showed that the risk of the Jeongdeung-hae passage is the highest due to higher risk level of some risk factors(water movements, complexities, tug boats, pilotage, VTS) than the other sectors. The result of this evaluation is in accord with the analysis results of the other studies using various qualitative or quantitative risk analysis methods at the same sea areas.

• Fire Science and Engineering
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• v.7 no.1
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• pp.17-29
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• 1993

The method has been proposed for the risk assessment of petro-chemical plant, specially which can evaluate relative risk levels on the materials and process-es. The each potential risk of materials and processes are derived numerically and combined these values, finally Fire and Explosion Index was found. Material factor was evaluated with the flammability and the reactivity and process factor with emprical factor called penalty. This F&EI can be performed for relative risk assesment at the whole plant and directely applicable at the line.

• Journal of the Korea Society of Computer and Information
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• v.14 no.10
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• pp.207-215
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• 2009

Recently, the research of the analysis of the crime spatial is increased by using the computer information technology and GIS (Geometric Information System) in order to prevent the urban crime so as to increase the urbanization rate. In this paper, a probability map formed by the raster is organized by the quantification of crime risk per the cell using the region property of the urban spatial information in the static environment. Also, a map of the risk probability is constructed based on the relative risk by the region property, the relative risk by the facility, the relative risk by the woody plant and the river, and so on. And, this integrated risk probability map is calculated by averaging the individual cell risk applied to the climatic influence and the seasonal factor. And, a probability map of the overall risk is generated by the interpretation key of the crime occurrence relative risk index, and so, this information is applied to the probability map quantifying the occurrence crime pattern. And so, in this paper, a methodology of the modeling and the simulation that this crime risk probability map is modified according to the passage of time are proposed.

• 한국방재학회:학술대회논문집
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• 2008.02a
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• pp.115-118
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• 2008

In this study, PROMETHEE(Preference Ranking Organization METHod for Enrichment Evaluations) which is one of the multi criteria decision making methods is applied to estimate the relative inundation risk of the urban subcatchment. For this purpose, five factors which have an effect on the inundation risk are selected and used to perform PROMETHEE. Those are elevation average, slope average, density of conduit, population and sediment yields per unit area of each subcatchment. Based on them, PROMETHEE is performed and the relative inundation risk for each subcatchment is estimated. Sensitivity anlysis is conducted to evaluate each factor's effect on subcatchment and it is found that suggested method can be used to establish a practical guide to mitigate the inundation.

• The Journal of the Korean Society for Microbiology
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• v.35 no.4
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• pp.317-324
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• 2000

Candida albicans is one of the most frequently isolated fungal pathogens in human. Recently, the prevalence of candida infection has markedly increased, partially due to the increase of immunocompromised hosts. Proposed virulence factors of the pathogenic Candida are the ability to form hyphae to adhere to epithelial cell surfaces, and to secrete acid proteinases and phospholipases. We measured the relative cell surface hydrophobicity (CSH) and the ability of proteinase production (PROT), phospholipase production (PLase), adherence to host epithelium (ADH), and hyphal transition (Germ). The relative risk of virulence factors was analyzed by lethality test in murine model of hematogeneously disseminated candidal infection. According to Cox's proportional hazard analysis, the statistically significant virulence factors were PROT, ADH, and CSH. PROT was the highest risk factor of them. To evaluate the applicability for the diagnosis and treatment of Candidiasis, we examined the protective effect of the active and passive immunizations with the materials purified from virulence factors and antibodies to them in Candia-infected mice model. The mean survival times of active and passive immunized groups were slightly longer than those of non-immunized groups.

• The Korean Journal of Community Living Science
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• v.22 no.3
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• pp.429-444
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• 2011

The objective of this study was to identify the risk factor and protection factor related to suicide ideation in each life course based on an ecological-system perspective. A questionnaire was carried out for 393 adolescents, 473 adults and 376 aged men living nationwide. The results are as follows. First, the suicide ideation was low with 1.78 points in the full mark of 5 points. Second, the difference in suicide ideation, depression, hopelessness, stress in the organic system variables, family solidarity in the micro system variables, intermediate system variables, residence, the existence/inexistence of counselling center and the influence of mass media in mezo system variables in each life course were significant. Third, the relative influence of organic system variables on the suicide ideation were largest in all life courses. Further, the depression and the influence of mass media in all life courses were a risk factor of suicide ideation and stress was also a risk factor of suicide ideation in the case of adolescents and the aged. When examining protection factors of suicide ideation, family solidarity, minute as it is, works as the protection factor of suicide ideation in the case of adolescents. For the adults, living in a metropolis was a protection factor from suicide ideation. For the aged, family solidarity, family history of suicide and adult children's attention to their friends and neighbors (intermediate system variable) were protection factors from suicide ideation. I suggested that policy, service, counseling and educational program proper to each life course were necessary to lower risk factors of suicide ideation and to improve protection factors.

• Journal of Navigation and Port Research
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• v.39 no.6
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• pp.493-498
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• 2015

When VTSOs(Vessel Traffic Service Operators) determine the degree of collision risk of two vessels, they consider comprehensively information about each vessel's course, speed, DCPA, TCPA and encountering situation. In this study, we proposed an algorithm in which two relative bearings as information about two vessel's encountering situation are used to evaluate the degree of collision risk. In order to verify whether the proposed algorithm is reasonable, we set twenty encountering situations and conducted a survey of collision risk on fifty three VTSOs about those situations. By comparing the degrees of collision risk with the proposed algorithm to the results of the survey, we found that relative bearing at CPA is very important factor for VTSO to recognize the level of collision risk when two vessels are in encountering situation.

• Nuclear Engineering and Technology
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• v.47 no.3
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• pp.362-379
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• 2015

In this study, Nuclear Power Plant (NPP) construction schedule delay risk assessment methodology is developed and the construction delay risk is assessed for turnkey international NPP projects. Three levels of delay factors were selected through literature review and discussions with nuclear industry experts. A questionnaire survey was conducted on the basis of an analytic hierarchy process (AHP) and Relative Importance Index (RII) methods and the schedule delay risk is assessed qualitatively and quantitatively by severity and frequency of occurrence of delay factors. This study assigns four main delay factors to the first level: main contractor, utility, regulatory authority, and financial and country factor. The second and the third levels are designed with 12 sub-factors and 32 sub-sub-factors, respectively. This study finds the top five most important sub-sub-factors, which are as follows: policy changes, political instability and public intervention; uncompromising regulatory criteria and licensing documents conflicting with existing regulations; robust design document review procedures; redesign due to errors in design and design changes; and worldwide shortage of qualified and experienced nuclear specific equipment manufacturers. The proposed combined AHP-RII methodology is capable of assessing delay risk effectively and efficiently. Decision makers can apply risk informed decision making to avoid unexpected construction delays of NPPs.