• Explosives and Blasting
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• v.18 no.2
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• pp.7-13
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• 2000

Abstract The characteristics of bed rock in the study area was classified by means of the crack coefficient estimated from the seismic velocities of in-situ and intact rocks. Various statistical methods were investigated in order to minimize the possible errors in estimating the predictive equation of blasting vibration and to enhance the determination coefficient $R^2$, for more reliable estimation. The determination coefficient showed the highest in the analysis for those groups using weighting function with the number of samples. The analysis for the weighting function employed with standard coefficient and variance also enhanced the determination coefficients significantly compared to the others, but the reliability was slightly lower than results obtained former method. Therefore the most reliable predictive equation of blasting vibration was found to be obtained from a regression analysis of the mean vibration level using the weighting of same distance groups within 15m with the same explosive charge weight per delay. The coefficients, K and n 317.4 and -1.66, respectively, when using the square root scaling, and 209.9 and -1.66, respectively, when using the cube root scaling. The analysis also showed that the square root scaling may be used in the distance less than 31m form the blast source, and the cube root scaling in the distance more than 31m for safe design.

• Science of Emotion and Sensibility
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• v.14 no.1
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• pp.165-174
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• 2011

Recent years have witnessed that IT-convergence technology has become the most important issue in the global market. Along with this trend, demand for PSS(i.e., Product-Service Systems) design has been rapidly increased in the smart clothing market. A case of the PSS design research, this study aimed to identify optimum conditions for weaving of POF-based flexible textile display(abbreviated as "PFTD") for mountaineer wear with safe-guard function regarding luminescent properties. Based on the findings regarding the optimum weaving condition of PFTD, several designs of mountaineer wear were suggested in this study. A total of 15 PFTD samples were prepared under various weaving conditions of weave structures and density of POF, and the luminance values of each sample were measured. As the results, the types of PFTD with structures and density of 'satin 3:1', 'satin 2:1', 'twill 3:1' and 'twill 2:1' indicated relatively higher luminescence. And based on the results and recent sports fashion trends, two suited mountaineering wears applying PFTD were illustrated in this study.

• Journal of Korean Society of Transportation
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• v.30 no.4
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• pp.43-59
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• 2012

Assuming a completed Smart Highway road & communication environment that allows real-time information collection and transmission of road traffic condition ahead, the purpose of this study is to develop a plan for inducing a network-level safe driving pattern by providing road traffic condition and safety information to multiple drivers through a road information provision device. In this study, the device with a function that displays different colors according to the hazard level to the existing delineator has been named 'Smart Delineator'. Smart Delineator is a device that provides not only alignment information but also safety information for drivers to receive real-time warning information and intuitively recognize road traffic condition ahead so that drivers can respond. To examine the effects of safety driving inducement level on drivers, a simulation test was conducted using driving simulator as well as a satisfaction survey. The result showed that the Smart Delineator was able to identify the location of occurrence and affecting driving according pattern, either adhering to recommended speed or reducing speed according to the pre-defined hazard level.

• Journal of the Korean Society of Safety
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• v.31 no.1
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• pp.95-104
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• 2016

In general, the crash reduction effect of the rumble strip is reported to be about 30% in Korea, while it is about 40-60% in the United States. However, the effect is erroneously overestimated because the simple comparison was only made before and after the installation. Accordingly, this study will reassess the crash reduction effect of the rumble strip. The study will also examine the former's geometric characteristics as well as its effect on the causes of the crash. This study analyzed the crash effect while taking into consideration the changes in the horizontal and vertical alignment, including the width of pavement shoulders, using the crash data for two years before and after the installation of the rumble strip. The types of crash caused by the rumble strip were identified using the classification discriminant function. The crash effect on the rumble strip is estimated to be 28.3%, but the pure effect, with the exception of the effect by other elements, was analyzed to be 7.4%. For each expressway design element, the downhill section (2.0-3.0%), the section with less than 3,000 m and more than 10,000 m of the curve radius, and the section with less than 3.0 m of the pavement shoulder width were found to be effective in crash reduction. For each cause of crash, the rumble strip was analyzed to be effective in the reduction of crash caused by "not keeping the safe distance", "sleeping", "negligence in keeping eyes forward", and "excessive handle operation". In particular, the rumble strip was analyzed and seen to be especially effective in preventing crash caused by "not keeping a safe distance," and "sleeping". The installation of the rumble strip was found to be effective in the prevention of crash caused by "not keeping the safe distance" and "sleeping". The results of this study may thus be used in deciding the causes of crash and the installation location of the tailored rumble strip that would be suitable for the geometric characteristics of the roads. This study will also be helpful in the establishment of future traffic safety measures.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.20 no.6
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• pp.299-312
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• 2021

Autonomous vehicles using V2X can drive safely information on areas outside the sensor coverage of autonomous vehicles conventional autonomous vehicles. As V2X technology has emerged as a key component of autonomous vehicles, research on V2X security is actively underway research on risk analysis due to failure of V2X communication is insufficient. In this paper, the service scenario and function of autonomous driving system V2X were derived by presenting the intersection scenario of the autonomous vehicle, the malfunction was defined by analyzing the hazard of V2X. he ISO26262 Part3 process was used to analyze the risk of malfunction of autonomous vehicle V2X. In addition, a fault injection scenario was presented to verify the fail-safe of the simulation-based intersection scenario.

• Journal of the Korean Association of Geographic Information Studies
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• v.26 no.3
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• pp.85-96
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• 2023

This study developed and evaluated a safe route guidance service for electric personal assistive mobility device used mainly by the mobility impaired people to improve their mobility. Thirteen underlying factors affecting the mobility of electric personal assistive mobility device have been derived through a survey with the mobility impaired people and employees in related organizations in Busan Metropolitan City. After assigning safety scores to individual factors and identifying the relevant factors along routes of interest with an object detection AI model, the safe route for electric personal assistive mobility device was provided through an optimal path-finding algorithm. As a result of comparing the general route of T-map and the recommended route of this study for the identical routes, the latter had relatively fewer obstacles and the gentler slope than the former, implicating that the recommended route is safer than the general one. As future works, it is necessary to enhance the function of a route guidance service based on the real-time location of users and to conduct spot investigations to evaluate and verify its social acceptability.

• Asian Pacific Journal of Cancer Prevention
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• v.14 no.8
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• pp.4529-4532
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• 2013

Background: Acute normovolemic hemodilution (ANH) has been widely used to prevent the massive blood loss during hepatic carcinoma. The influences of ANH on coagulation function are still controversy, especially in elderly patients. The study observed ANH effects on coagulation function and fibrinolysis in elderly patients undergoing the disease. Materials and Methods: Thirty elderly patients (aged 60-70 yr) with liver cancer (ASA I or II) taken hepatic carcinectomy from February 2007 to February 2008 were randomly divided into ANH group (n=15) and control group (n=15). After tracheal intubation, patients in ANH group and control group were infused with 6% hydroxyethyl starch (130/0.4) and Ringer's solution, respectively. Blood samples were drawn from patients in both groups at five different time points: before anesthesia induction (T1), 30 min after ANH (T2), 1 h after start of operation (T3), immediately after operation (T4), and 24 h after operation (T5). Then coagulation function, soluble fibrin monomer complex (SFMC), prothrombin fragment (F1+2), and platelet membrane glycoprotein (CD62P and activated GP IIb/GP IIIa) were measured. Results: The perioperative blood loss and allogeneic blood transfusion were recorded during the surgery. The perioperative blood loss was not significantly different between two groups (p>0.05), but the volume of allogeneic blood transfusion in ANH group was significantly less than in control group ($350.0{\pm}70.7$) mL vs. ($457.0{\pm}181.3$) mL (p<0.01). Compared with the data of T1, the prothrombin time (PT) and activated partial thromboplastin time (APTT) measured after T3 were significantly longer (p<0.05) in both groups, but within normal range. There were no significant changes of thrombin time (TT) and D-dimer between two groups at different time points (p>0.05). SFMC and F1+2 increased in both groups, but were not statistically significant. PAC-1-positive cells and CD62P expressions in patients of ANH group were significantly lower than those at T1 (p<0.05) and T2-T5 (p>0.05). Conclusions: ANH has no obvious impact on fibrinolysis and coagulation function in elderly patients undergoing resection of liver cancer. The study suggested that ANH is safe to use in elderly patients and it could reduce allogeneic blood transfusion.

• The Korean Journal of Nuclear Medicine
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• v.11 no.1
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• pp.49-58
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• 1977

For the assessment of antithyroid effect of lithium carbonate, it was administered to the 17 hyperthyroid and 5 euthyroid patients, who visited the Seoul National University Hospital from Jan. to Aug., 1977. Thyroid function tests were performed just before the administration of Lithium carbonate, 2 weeks and 2 months after lithium treatment. The results were as follows; 1) In the 5 euthyroid patients, no significant changes in thyroid function tests were obtained before and after lithium treatment. 2) In the 17 hyperthyroid patients, the values of the $T_3RIA$ were $370{\pm}121ng/dl$ 2 weeks after lithium treatment as compared with $506{\pm}121ng/dl$ before the administration, of which the mean percentage fall was 26.9%. $T_3RU$ was varied from $56.8{\pm}8.0%\;to\;47.3{\pm}8.1%$ (16.7% in mean percentage fall), $T_4$ was changed from $24.2{\pm}2.4ug/dl\;to\;22.0{\pm}4.2ug/dl$ (9.1% in mean fall), and $T_7$, from $13.82{\pm}2.25\;to\;10.55{\pm}3.12$ (23.7% in mean fall). 3) In the 5 hyperthyroid patients, serial thyroid function tests were performed 2 weeks and 2 months later. The mean percentage falls of $T_3RIA$ were 36.6 and 61.3%, 2 weeks and 2 months after lithium treatment respectively. Those of $T_3RU$ were 17.5 and 35.1%, those of $T_4$ were 20.4 and 44.0%, $T_7$, 35.0 and 60.7%. 4) Approximately $45{\sim}60%$ of mean fall in thyroid function tests were obtained within the second week. Normal thyroid function tests were observed in 2 among 17 patients within the second week, and 2 among 5 patients within the second month. 18 patients, however, became clinically euthyroid within the 4th week. 5) Single case of hypothyroidism was experienced, and 5 patients (29.4%) complained mild side effects. Lithium salts could be safely administered to hyperthyroid patients who are allergic to thioamides or iodine. Its use is indicated in cases of acute thyrotoxicosis in which it's necessary to reduce hormone levels very rapidly, and lithium-thioamides drug combination is a highly effective and safe means of initial routine control of hyperthyroidism.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.38 no.5
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• pp.467-476
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• 2010

For the very light jet aircraft design, the design baseline configuration has been selected using the logical decision making process, and the design optimization problem is formulated by considering the airworthiness regulations as design constraints. Airworthiness regulations are the minimum requirements for the safe aircraft flight and must be considered from the conceptual design stage. After carefully selecting the airworthiness constraints and the user specified requirements, a series of design making models including the affinity diagram, nested column diagram, quality function deployment (QFD), Pugh concept selection matrix, are used to find and evaluate alternative configuration baselines. From the feasible design space searching process, the best altenative design, which satisfies the airworthiness constraints while excluding the user subjective decisions as much as possible, has been successfully derived.

• Journal of Sasang Constitutional Medicine
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• v.25 no.4
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• pp.373-383
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• 2013

Objectives The purpose of this clinical trial was evaluate the safety and efficacy of Mahwangjeongcheon-tang (MJT). Methods Twenty six volunteers were recruited as subjects. They were divided into two groups, which were MJT test group and placebo group. The investigated items related to the safety were the weight, the results of renal function and liver function. The investigated items related to the efficacy are the results of the spirometer, the clinical asthma measurement scale in oriental medicine-V (CAMSOM-V) and the quality of life questionnaire for adult Korean asthmatics (QLQAKA). Results There are no difference in the weight, the results of the renal functions and the liver functions between MJT test group and placebo group. There are the some differences in the result of the questionnaires related to the efficacy between MJT test group and placebo group. The significant difference were observed in the CAMSOM-V at the 4th visit. Conclusion MJT is the safe and effective herbal prescription that is useful to the asthma patients.