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A Study on Variable Speed Limit Strategies in Freeway Work Zone Using Multi-Criteria Decision Making Process (다기준 의사결정기반 고속도로 공사구간 VSL전략에 관한 연구)

  • Park, Juneyoung;Oh, Cheol;Chang, Myungsoon
    • Journal of Korean Society of Transportation
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    • v.31 no.5
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    • pp.3-15
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    • 2013
  • The purpose of this study is to propose a methodology for operating variable speed limit (VSL) strategies in freeway work zones. A notable feature in this study is to incorporate a multi-criteria decision making process into deriving better VSL strategies. Decision criteria in this study include operational efficiency, safety, and environmental impacts. Travel speed, acceleration noise, and CO2 were used as performance measures for evaluating VSL strategies. A multi-criteria value function was developed through an analytical hierarchical process (AHP) for representing expert's knowledge. Then, a variety of VSL operations scenarios were investigated utilizing a microscopic traffic simulation suite, VISSIM. The proposed methodology would be useful in supporting more efficient, safer, and more environment-friendly traffic operations and control in freeway work zones.

The Change of the Phoria in Accordance with the Color and Concentration of the Color Lens (착색렌즈의 색상과 농도에 따른 원거리 사위도의 변화)

  • Choi, Hyun-Soo;Park, Sung-Jong;Lee, Seok-Ju;Jin, Moon-Seok;Jun, Jin;Ryu, Geun-Chang
    • Journal of Korean Ophthalmic Optics Society
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    • v.16 no.3
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    • pp.339-343
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    • 2011
  • Purpose: In this study, we investigated changes of phoria based on varying the color and concentration of the color in lenses. Methods: We measured distance phoria for 39 students who aged 20 to 40 with different concentrated lenes - red, gray, brown and green lenses in concentration 20%, 50% and 80%, respectively. Results: Subjects were divided into three groups which were orthophoria, esophoria and exophoria. Orthophoria in all the color and concentration, there were a few of the esophoria. Esophoria of average 2.07${\Delta}$,B.O showed that a slight increase in all colors and concentration, especially in brown lenses showed the greatest increase. Exophoria of average 3.82${\Delta}$,B.I showed that a slight decrease in all colors and concentration, especially in green lenses showed to 2.95${\Delta}$,B.I to the greatest decrease. Different concentration in same color had no specific tendency regarding phoria. Conclusions: The phoria must be considered when selecting color of the lens because of phoria is changeable by color of the lens. It is expected to study the criteria that minimize the asthenopia.

A Study on the Entry Path of Institute of the Translation of Korean Classics (한국고전번역원 번역인력의 진입경로에 대한 연구 - 2013년~2017년 번역인력을 중심으로 -)

  • Kwon, Kyongsoon
    • (The)Study of the Eastern Classic
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    • no.71
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    • pp.259-304
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    • 2018
  • In this paper, we analyzed and analyzed the entry path and the capacity of translation competent personnel who participated in the translation project for the last 5 years. For this purpose, the entry path of the translation workforce is classified as 'employee', 'research course', 'vt', and 'external expert'. And the number of manpower and the amount of translated manuscripts were examined by year. In addition, the average amount of manpower for one translator was also examined. As a result of the research and analysis, the proportion of the total translation companies in the translation business was in the order of external experts - from the research course - from the qualification examination - from the staff. The proportion of manuscripts is in the order of from the research course - external expert - from the qualification examination - from the staff. In addition, we surveyed and analyzed the present status of each of the translators and discussed the characteristics and problems of each business sector. In the translation of historical documents, the proportion of manpower is the largest in the research process, but the proportion of manuscripts is the highest in the qualification test, and that of the experts in the translation and special classics is significant. In addition, it was judged that translation work of translator was proceeding inefficiently by analyzing average manpower quantity of translation worker. In order to solve these problems, three plans were proposed: 'Need to plan the use of translation personnel based on business plan', 'Improvement of qualification examination for cross-country and translation committee members', 'Training of translation experts in specialized fields and expansion of entry routes'. Each of these measures must be validated and validated through detailed analysis and research. However, it is hoped that the translator will help the translation project by establishing a more systematic and planned business plan and a plan to utilize the translation workforce.

Basic Research for the Development of Collision Risk Model of Passing Vessels at an Anchorage (Safety Domain) (정박지 통항선박의 충돌위험 모델 개발을 위한 기초연구 - 정박지 통항선박의 안전 -)

  • Lee, Jin-Suk;Kwon, Yumin;Choi, Jung-Suk
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.27 no.1
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    • pp.67-73
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    • 2021
  • The purpose of this study is to obtain a safe area for a passing vessel between anchored vessels by developing a model to predict the collision risk, frequent collisions occur between the anchored vessel and the passing vessel through the anchorage. For this, this study selected the southern anchorage of Busan port, which is the largest harbor in Korea, as the target area and extracted and analyzed VTS (Vessel Traffic Service) data during the period in which anchored vessels were the most waited. The ratio of D/L for each bearing was obtained to determine the safe distance (D) passes based on the length (L) of the passing vessel between anchored vessels. Based on the average domain of the D/L ratio distribution, the percentage of anchored vessels within the scope of the pre-studied ship's domain was analyzed to obtain a domain reflecting the degree of risk of VTSOs. Further research will evaluate and analyze the collision risk of a passing vessel using Domain-watch, the minimum safe distance between anchored vessels, and the safe domain of a passing vessel through anchorage, to develop a model for VTS to manage anchorages more efficiently and safely.

A Study on Speed Limit Rules under Sailing Regulations - Focusing on the Perspective of VTS Control - (항법상 속력의 제한규칙에 관한 고찰 - VTS의 관제 관점에서 -)

  • Chong, Dae-Yul
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.2
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    • pp.254-261
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    • 2022
  • Every vessel shall proceed at a safe speed to avoid collision. Additionally, every vessel shall comply with the speed limit rules in the territorial water and internal waters of Korea. The VTS operator shall properly control the compliance of the vessel with the safe speed and speed limit rules. Safe speed under the COLREG 1972 is not explicitly stipulated in knots. However, under the Domestic law for traffic safety-specific sea areas, etc., the speed limit is specified in knots and complied with. This speed limit rule is mainly based on the 'speed made good over the ground'; however, in some places, it is based on the 'speed making way through the water'. In this paper, I analyzed marine accidents that occurred in the past 5 years and the rate of violation of speed limits. Furthermore, I reviewed safe speed under the COLREG 1972, speed limit rules under domestic and foreign laws, and cases of non-compliance with safe speed in the judgment of the Korea Maritime Safety Tribunal. Resultantly, I suggested in this paper that the speed limit rules in the domestic law must be observed by vessels to prevent marine accidents, and the rules which are stipulated in terms of 'speed making way through the water' must be revised as 'speed made good over the ground' such that the vessels can easily comply with them and the VTS operator can control the vessel properly.

Study on Effective Operational Plan of Maritime Safety Enforcement Task : Focus on Vessel Safety Management (해양안전 집행업무의 효율적 운영방안 연구 -선박안전 관리를 중심으로-)

  • Byungdoo Yun
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.28 no.7
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    • pp.1169-1178
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    • 2022
  • This study examines an effective operational plan of a maritime safety enforcement task that is distributed in the Ministry of Oceans and Fisheries and the Korea Coast Guard for maritime safety. Considering the sinking of the MV Sewol and Seohae vessels and the MV Hebei Spirit oil spill, normally marine safety accidents tend to not only damage human life, property, and marine environment but can also expand to disasters; therefore, precautionary measures are required. However, the Korean government takes superficial efforts in case of large-scale accidents. In case of the MV Sewol ferry, the government only focused on punishing the officials involved as a follow up and never mentioned any effective plan, such as "unification of maritime safety enforcement," in contrast to an advanced country. As a result, there are endless major and minor backward accidents. The probability of large-scale maritime accidents and backwardness accidents is increasing owing to vessels becoming large sized, high speed, and aged; sailors being unqualified; port traffic increase, development of marine leisure; and inefficiency dual marine safety systems. Therefore, based on the review of previous studies related to maritime safety, major advanced country's cases, and unified case of the vessel traffic service, this study suggests effective methods such as coastal vessel safety management, port state control and aid to navigation management, which are directly connected with maritime safety.

A Study on Hazards to Pilotage Safety in a Pilotage Area in the Busan Gamcheon Port (부산 감천항 도선구의 도선안전위해요소에 관한 연구)

  • Sei-hun Kim;Bong-kwon Choi;Ji-ung Choi;Tae-Seok Song;Young-soo Park;Dae-won Kim
    • Journal of Navigation and Port Research
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    • v.47 no.6
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    • pp.341-349
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    • 2023
  • Gamcheon Port, which is one of three major harbors in the Port of Busan, is being operated to load, discharge and transport a wide range of cargoes, including general cargo, fisheries, steel products, cement, etc,. The harbor, designated as a compulsory pilotage area, provides pilotage services in compliance with relevant laws and regulations for arrival and departure of vessels in the Gamcheon Port area. Some academic research on the marine traffic environment in Gamcheon Port has been conducted. However, the pilotage environment and hazards to pilotage safety in the port have yet to be studied. Therefore, in this research, the pilotage environment and hazards to pilotage safety were identified, and it was confirmed that there are hazards to pilotage safety, such as vessels installed poor facilities including damaged pilot boarding arrangements, vessels blocking pilot's view by her structures and fishing nets, vessels unable to communicate in English, vessels not following VTS's order. The hazards to pilotage safety were also stratified, and the importance of the hazards was verified in accordance with a survey based on Analytic Hierachy P rocess(AHP) for Busan Harbor pilots, and safety measures to secure pilotage safety were examined to secure the safety of vessels calling Gamcheon Port.

Respiratory Gas Exchange and Ventilatory Functions at Maximal Exercise (최대운동시의 호흡성 가스교환 및 환기기능)

  • Cho, Yong-Keun;Jung, Tae-Hoon
    • Tuberculosis and Respiratory Diseases
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    • v.42 no.6
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    • pp.900-912
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    • 1995
  • Background: Although graded exercise stress tests are widely used for the evaluation of cardiorespiratory performance, normal standards on respiratory gas exchange and ventilatory functions at maximal exercise in Koreans have not been well established. The purpose of this study is to provide reference values on these by sex and age, along with derivation of some of their prediction equations. Method: Symptom-limited maximal exercise test was carried out by Bruce protocol in 1,000 healthy adults consisting of 603 males and 397 females, aged 20~66 years. Among them VC, $FEV_1$ and MVV were also determined in 885 cases. All the subjects were members of a health center, excluding athletes. During the exercise, subjects were allowed to hold on to front hand rail of the treadmill for safety purpose. Results: The $VO_2\;max/m^2$, $VCO_2\;max/m^2$ and $V_E\;max/m^2$ were greater in males than in females and decreased with age. The RR max in men and women was similar but decreased slightly with age. The $V_T$ max was markedly greater in men but showed no significant changes with age in either gender. The mean of $V_T$ max/VC, $V_E$ max/MVV and BR revealed that there were considerable ventilatory reserves at maximal exercise even in older females. The regression equations of the cardinal parameters obtained using exercise time(ET, min), age(A, yr), height(Ht, cm), weight(W, kg), sex(S, 0=male; 1=female), VC(L), $FEV_1$(L) and $V_E$ max(L) as variables are as follows: $VO_2\;max/m^2$(L/min)=1.449+0.073 ET-0.007A+0.010W-0.006Ht-0.209S, $VCO_2\;max/m^2$(L/min)=1.672+0.063ET-0.008A+0.010W-0.005Ht-0.319S, VE max/$m^2$(L/min)=58.161+1.503ET-0.315A-9.871S or VE max/$m^2$(L/min)=47.873+6.548 $FEV_1$-5.715 S, and VT max(L)=1.497+0.223VC-0.493S. Conclusion: Respiratory gas exchange and ventilatory variables at maximal exercise were studied in 1,000 non-athletes by Bruce protocol. During exercise, the subjects were allowed to hold on to hand rail of the treadmill for safety purpose. We feel that our results would provide ideal target values for patients and healthy individuals to be achieved, since our study subjects were members of a health center whose physical fitness levels were presumably higher than ordinary population.

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Comparative Study of Effects of 'Intramuscular Bee Venom Herbal Acupuncture' and 'Intracutaneous Bee Venom Herbal Acupuncture' in Knee Osteoarthritis Patients (퇴행성 슬관절염 환자에서 근육 내 봉독약침과 피내 봉독약침의 효능 비교연구)

  • Kim, Haeng-Beom;Lee, Ro-Min;Lee, Min-Ho;Choi, Yang-Sik;Kim, Jong-In;Lee, Yun-Ho;Lee, Jae-Dong
    • Journal of Acupuncture Research
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    • v.25 no.2
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    • pp.151-164
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    • 2008
  • Objectives : This study was designed to compare the effects on Korean Western Ontario and McMaster Universities Osteoarthritis Index(KWOMAC), 36-ltems Short-Form Health Survey(SF-36), Visual Analog Scale(VAS) and Nine Point Scale between 'Intramuscular Bee Venom Herbal Acupuncture' and 'Intracutaneous Bee Venom Herbal Acupuncture' in knee osteoarthritis patients for 4weeks. Methods : All the voluntary subject were diagnosed as knee osteoarthritis. Patients were randomly assigned either to two groups : Intramuscular bee venom herbal acupuncture treatment group(IM-BV group) or Intracutaneous bee venom herbal acupuncture treatment group(IC-BV group). The IM-BV group received bee venom herbal acupuncture intramuscularly on muscles closest to the pathologic site on ultrasonography. The IC-BV group received bee venom herbal acupuncture intracutaneously on $LE_{110}$, $LE_{201}$, $ST_{35}$, $ST_{36}$ and $LR_8$. Bee venom herbal acupuncture was applied twice a week for 4 weeks by an oriental medical doctor at Kyung-hee Oriental Medical Hospital. Both groups were checked of pathologic site by ultrasonography before treatment and follow up after four-week treatment. The patients were assessed by KWOMAC and SF-36 before and after four-week treatment. The changes in patients' pain was measured by VAS before treatment and after one-, two-, three- and four-week treatment. The patients' overall treatment outcome assesment was measured by Nine Point Scale after four-week treatment. Results : The results were as follows ; 1. The IM-BV group showed significant improvement on total, pain, stiffness and physical function in KWOMAC, and the IC-BV group showed significant improvement on total and physical function in KWOMAC after 4weeks compared to the pre-treatment. In KWOMAC, the IM-BV group showed more improvement on average compared to the IC-BV group, but there were no significant difference between two groups. 2. The IM-BV group showed significant improvement on VAS after one-week treatment. The IC-BV group showed significant improvement on VAS after two-week treatment. But there were no significant difference between two groups. 3. The IM-BV group showed significant improvement on physical functioning(PF) and bodily pain(BP) in SF-36, and the IC-BV group showed significant improvement on vitality(VT) and bodily pain(BP) in SF-36 after 4weeks compared to the pre-treatment. But there were no significant difference between two groups. 4. 88.2% of IM-BV group and 93.3% of IC-BV group graded their improvement as 'Fair' or better on Nine Point Scale. But there were no significant difference between two groups. Conclusions : This study suggests that in the treatment of knee osteoarthtitis patients, effects of 'Intramuscular Bee Venom Herbal Acupuncture' were not different from 'Intracutaneous Bee Venom Herbal Acupuncture' statistically. But both treatment showed effects on pain and physical function in knee osteoarthtitis patients.

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$^{17}O$ NMR Study On Water Excharge Rate of Paramagnetic Contrast Agents ($^{17}O$ NMR 기법을 이용한 상자성 자기공명조영제의 물분자 교환에 관한 연구)

  • Yongmin Chang;Sung Wook Hong;Moon Jung Hwang;Il Soo Rhee;Duk-Sik Kang
    • Investigative Magnetic Resonance Imaging
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    • v.5 no.1
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    • pp.33-37
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    • 2001
  • Purpose : The water exchange rate between bulk water and bound water is an important parameter in deciding the efficiency of paramagnetic contrast agents. In this study, we evaluated the water exchange rates of various Gd-chelates using oxygen-17 NMR technique. Material and Methods : The samples (Gd-DTPA, Gd-DTPA-BMA, Gd-DOTA, Gd-EOB-DTPA) were prepared by mixing 5% $^{17}O-enriched$ water (Isotech, USA). The pH of the samples was adjusted to physiological value [pH=7.0] by buffer solution. The variable temperature $^{17}O-NMR$ measurements were performed using Bruker-600 (14.1 T, 81.3 MHz) spectrometer. Bruker VT-1000 temperature control units were used to stabilize the temperature. The $^{17}O$ spin-spin relaxation times (T2) were measured using Carr-Purcell-Meiboom-Gill (CPMG)I pulse sequence with 24 echo trains. The variable temperature T2 relaxation data were then fitted into Solomon-Bloembergen equations using least square fit algorithm to estimate the water exchange times. Results : From the measured $^{17}O-NMR$ relaxation rates, the determined water exchange rates at 300K are $0.42{\;}{\mu}s$ for Gd-DTPA, $1.99{\;}{\mu}s$ for Gd-DTPA-BMA, $0.27{\;}{\mu}s$ for Gd-DOTA, and $0.11{\;}{\mu}s$ for Gd-EOB-DTPA. The Gd-DTPA-BMA showed slowest exchange whereas Gd-EOB-DTPA had fastest water exchange rate. In addition, it was found that the water exchange rates (${\tau}_m$) of all samples had exponential temperature dependence with different decay constant. Conclusion : $^{17}O-NMR$ relaxation rate measurements, when combined with variable temperature technique, provide a solid tool for studying water exchange rate, which is very important in investigating the detailed mechanism of relaxation enhancement effect of the paramagnetic contrast agents.

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