• Title/Summary/Keyword: Continuous Risk Profile

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Identifying Hotspots on Freeways Using the Continuous Risk Profile With Hierarchical Clustering Analysis (계층적 군집분석 기반의 Continuous Risk Profile을 이용한 고속도로 사고취약구간 선정)

  • Lee, Seoyoung;Kim, Cheolsun;Kim, Dong-Kyu;Lee, Chungwon
    • Journal of Korean Society of Transportation
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    • v.31 no.4
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    • pp.85-94
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    • 2013
  • The Continuous Risk Profile (CRP) has been well known to be the most accurate and efficient among existing network screening methods. However, the classical CRP uses safety performance functions (SPFs) which require a huge investment to construct a database system. This study aims to suggest a new CRP method using average crash frequencies of homogeneous groups, instead of SPFs, as rescaling factors. Hierarchical clustering analysis is performed to classify freeway segments into homogeneous groups based on the data of AADT and number of lanes. Using the data from I-880 in California, the proposed method is compared to other several network screening methods. The results show that the proposed method decrease false positive rates while it does not produce any false negatives. The method developed in this study can be easily applied to screen freeway networks without any additional complex database systems, and contribute to the improvement of freeway safety management systems.

Characteristics of Night Specialized Traffic Accident Hotspot Using Continuous Risk Profile (CRP) Analysis (CRP (Continuous Risk Profile) 분석을 이용한 야간 특화 교통사고 다발구간의 특성)

  • Kim, Heesoo;Oh, Heungun
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.41 no.1
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    • pp.49-56
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    • 2021
  • The purpose of this study is to develop a methodology to select a cluster of night traffic accidents using CRP (Continuous Risk Profile) analysis. the other purpose of this study is to present the characteristics of the traffic accident cluster section selected at night using CRP analysis. The CRP analysis was performed considering traffic volume of target routes through traffic accident data. In addition, variables were set according to the freeway sections. the method of subtracting the daytime CRP from the nighttime CRP was used to analyze the nighttime traffic accident. As a result, Using the CRP analysis, the sections of hotspot were identified and plotted based on traffic accidents. Also, the sections where traffic accidents are frequent were those where IC or Tunnels were installed, and there was a deviation from the general section. In conclusion, CRP analysis could be used to calculate the frequent section of specialized traffic accidents at night, and it was selected as a point in need of improvement due to the frequent occurrence of specialized traffic accidents at night in the section where IC or tunnel facilities are installed. In addition, it is inferred that the number of specialized traffic accidents at night in the section where IC or tunnel facilities are installed is a factor in the problem of night visibility due to lighting facilities.

Efficacy of Hormone Replacement Therapy on Lipid Profile and Bone Mineral Density in Postmenopausal Women: Continuous vs. Sequential Treatment (페경기 여성에서 호르몬 대체요법의 지질대사 및 골밀도에 대한 효과: 지속적 요법과 순차적 요법의 비교)

  • Lee, Chang Yun;Lee, Sukhyang
    • Korean Journal of Clinical Pharmacy
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    • v.10 no.3
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    • pp.101-106
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    • 2000
  • Menopausal women experience urogenitory and vasomotor symptoms with increased risk of osteoporosis and cardiovascular diseases, which can be reduced by hormone replacement therapy. However unopposed estrogen therapy has been associated with an increased risk of endometrial hypeiplasia or cancer. The objectives of this study were to compare effects of continuous vs. sequential hormone replacement therapy (HRT) on lipid profile, bone mineral density and menopausal symptoms of postmenopausal women and to assess how they perceive the menopause and HRT culturally. In this retrospective study, women in menopause longer than 6 months, normal in the mam-mogram and Papanicolaou smear, cholesterol level lower than 190 mg/dL or triglyceride level lower 4han 500 mg/dL were treated with Srogen (conjugated equine estrogen 0.625 mg tablet) and Provera (medroxyprogesterone acetate 2.5 mg tablet) for continuous treatment(CT) or Cycloprogynova (Estradiol valerate 2 mg and Norgestrel 0.5 mg complex tablet) for sequential treatment(ST). They were evaluated for lipid profile, bone mineral density, menopausal symptoms, side effects and their perception of menopause and HRT. As results, total sixty-seven patients out of ninety-four enrollees were included in final analysis (33 in continuous therapy, 34 in sequential therapy). There were significant decrease in total cholesterol ($15.04\pm3.17$, p=0.0001), LDL ($19.72\pm3.27$, p=0.0001), and increase in HDL ($5.89\pm1.63$, p=0.0001). Bone minora) density increased significantly with HRT ($0.02\pm0.11$, p=0.0001). But, there were no significant differences in change of lipid profile between continuous and sequential therapy: Total cholesterol, $13.12\pm4.7\;vs.\;16.91\pm4.3;\;LDL\;20.53\pm4.1\;vs.\;18.93\pm5.12:HDL\;7.15\pm2.3\;vs.\;4.67\pm2.2,\;p>0.05$. Incidences of flush reduced from $75\%\;(CT)\;to\;3.13\%\;and\;71.88\%\;(ST)\;to\;9.35\%$. The change of endometrium and breast were found 3 (CT) and 5 (ST) women, respectively. Most of women recognized that HRT is necessary $(70\%)$ for postmenopausal period but did not understand well the cardiovascular protective effect. In conclusion, hormone replacement therapy was effective in improving lipid profile, bone mineral density and menopausal symptoms in both continuous and sequential treatments with similar efficacy.

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An Analysis of the Hazardous Highway Segments Using Continuous Risk Profile Method (고속도로 사고잦은 지점 분석방법 연구)

  • Lee, Soo-Il;Yu, Jun-Seok
    • Journal of the Korean Society of Safety
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    • v.25 no.6
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    • pp.180-185
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    • 2010
  • We have to develop more correct and systematic way to choose Hazardous Highway Segments. In this research, we applied CRP(Continuous Risk Profile) technique which developed by UC Berkeley Traffic Safety Center in year of 2007, and can analyze yearly dangerous level tendency of continuity in the route of main road that is under California Department of Transportation(Caltrans). We changed standard of CRP to suit in Korean circumstance with consideration in radius of curve and traffic volume. For the verification by actual accident data, we embodiment the CRP by using the data from total of 587 case of accident in latest 10 years in Gyeong-Bu Highways, the amount of 56km. Finally, the effectiveness of technique in this research has been verified by obtained same result with current method for Hazardous Highway Segments. In addition, when calculating the Hazardous Highway Segments with technique that presented in this research we obtained following statements. First, identified dangerous level of continuity in the route by using CRP. Second, Accurate of Actual Hazardous Highway Segments selection has been developed by using last 10 year's data and profile making which provide simplicity analyze of Tendency. Third, after reforming the way of selection, effective range has been wider than former selection and it gives advantage for the policy side.

An Evaluation Models for R&D Projects Selection (연구개발과제 선정을 위한 단계별 평가모형)

  • 이상철;하정진;김성희
    • Journal of Korean Society of Industrial and Systems Engineering
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    • v.17 no.31
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    • pp.73-80
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    • 1994
  • Sequentiality in decision making is an inherent characteristic of the R&D Process, Conceptual changes are noted during the Course of the Project which represent a continuous improvement in the quality of the data available during the various project stages. In this paper, Eight characteristic types of project evaluation models have been developed economic index models, portfolio models, decision theory models, risk analysis models, frontier models, scoring models, profile models and checklists. Each of these will be critically reviewed and appraised.

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Continuous-authentication Method based on the Risk Profile associated with Context-awareness to Lock Smart Devices (스마트 기기 잠금을 위한 상황인지 위험도기반의 지속인증기법)

  • Kim, Jihwan;Lee, Younho
    • Journal of KIISE
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    • v.43 no.11
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    • pp.1259-1269
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    • 2016
  • In order to block the access of the information in the smartphone of a user by other users, it is checked if the current user is the owner or not in the smartphone authentication process, whenever a user begins to use a smartphone. This makes smartphone users in front of frequent smartphone authentications, which leads significant inconvenience to them. Because of such inconvenience, users tend not to use the smartphone authentication anymore. Finally, their smartphones become very vulnerable against malicious access. This paper proposes a progressive authentication method on the android-platform in order to solve the problem described above. With the proposed method, smartphones can identify relevant risks based on users' past experiences and determine whether an authentication is needed. Because authentication occurs only when the identified risk level is high, it can achieve both a high-level of security in the high-level risk situation and user convenience in the low-level risk situation.