• 화약ㆍ발파
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• 제9권4호
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• pp.3-12
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• 1991

The cautious blasting works had been used with emulsion explosion electric M /S delay caps. Drill depth was from 3m to 6m with Crawler Drill 70mm on the calcalious sand stone (soft-moderate-semi hard Rock) . The total numbers of feet blast were 88. Scale distance were induces 15.52-60.32. It was applied to Propagation Law in blasting vibration as follows .Propagtion Law in Blasting Vibration V=k(D/W/sup b/)/sup n/ where V : Peak partical velocity(cm/sec) D : Distance between explosion and recording sites(m) W ; Maximum Charge per delay -period of eight milliseconds or more(Kg) K : Ground transmission constant, empirically determind on the Rocks, Explosive and drilling pattern ets. b : Charge exponents n : Reduced exponents Where the quantity D/W/sup b/ is known as the Scale distance. Above equation is worked by the U.S Bureau of Mines to determine peak particle velocity. The propagation Law can be catagrorized in three groups. Cabic root Scaling charge per delay Square root Scaling of charge per delay Site-specific Scaling of charge delay Charge and reduction exponents carried out by multiple regressional analysis. It's divided into under loom and over loom distance because the frequency is varified by the distance from blast site. Empirical equation of cautious blasting vibration is as follows. Over 30m--under 100m----V=41(D/ W)/sup -1.41/-----A Over l00m---------V=121(D/ W)/sup -1.56/-----B K value on the above equation has to be more specified for furthur understand about the effect of explosives. Rock strength, And Drilling pattern on the vibration levels, it is necessary to carry out more tests.

• Bulletin of the Korean Chemical Society
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• 제34권11호
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• pp.3284-3288
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• 2013

This paper describes first development and validation of pentafluorophenylprophyl ligand-based liquid chromatography coupled to tandem mass spectrometry (PFPLC-MS/MS) method to determine metformin, a highly polar compound, in human plasma. Metformin and Phenformin (internal standard) were extracted from human plasma 50 ${\mu}L$ with a single-step protein precipitation. The chromatographic separation was performed using a linear gradient elution of mobile phase involving 5.0 mM ammonium formate solution with 0.1% formic acid (A) and acetonitrile (B) over 3.0 min of run time on a Phenomenex Luna PFP column. The detection was performed using a triple-quadrupole tandem mass spectrometer (Waters Quattro micro) with electrospray ionization in the mode of positive ionization and multiple-reaction monitoring (MRM). The developed method was validated with 5.0 ng/mL of lower limit of quantification (LLOQ). The calibration curve was linear over 5-3000 ng/mL of the concentration range ($R^2$ > 0.99). The specificity, selectivity, carry-over effect, precision, accuracy and stability of the method met the acceptance criteria. The method developed in this study had had rapidness, simplicity and ruggedness. The reliable method was successfully applied to high throughput analysis of real samples for a practical purpose of a pharmacokinetic study.

• 대한물리치료과학회지
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• 제13권2호
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• pp.37-45
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• 2006

The purpose of this study was to determine the effect of treadmill training on gait, balance, and trunk control in a patient with hemiparesis. A female subject who had suffered a left hemiparesis 12 months previously was selected for this study. A single subject ABA design was used. Eight data-collection sessions were conducted during each of three phases (baseline-intervention-withdrawal). During baseline and withdrawal phases, the treatment based on Bobath approach was performed for the subject, and during the intervention phase, treadmill walking training was added. Assessment tools were made using the 10 m walk test, Rivermead Visual Gait Assessment(RVGA), Berg Balance Scale(BBS), and a seated Lateral Reach Test(LRT). During the intervention phase, the time measured in 10 m walk test and the scores of RVGA and BBS were significantly improved, and the number of steps in 10 m walk test and LRT showed a small improvement. During withdrawal phase, the time measured in 10 m walk test and the scores of RVGA and BBS were shown the carry-over effect. This findings indicate that treadmill training has significant effect to gait function and balance in a patient with chronic hemiparesis.

• 한국전문물리치료학회지
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• 제9권2호
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• pp.83-96
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• 2002

The purpose of this study was to determine the effect of lift to the shoe of the affected limb on gait patterns in subjects with hemiplegia. The subjects of this study were 18 post-stroke hemiplegics. For the study, insole of the paretic side was lifted 10mm higher, and duration of static weight bearing, dynamic weight bearing and stance phase were measured from one cycle of the gait, before and after the lift application. For the measurement of carry-over effect of lift, we got data of those three items prior to and 3 weeks after lift application and 3 days after removal of the lift. Static weight bearing was significantly increased both just after and continuous application of lift for 3 weeks than before. Dynamic weight bearing was significantly decreased in heel contact and footflat phases only when just after application of the lift, without any change after 3 weeks application. In heel-off phase, dynamic weight bearing did not show any significant difference between before and just after application of lift whereas significantly decreased after 3 weeks application. Duration of stance phase was not changed among anytime of application. According to this study, lift applied to the shoe of the peretic limb was effective in inducing static weight bearing in the paretic limb, but did not significantly effect dynamic weight bearing on gait patterns. This study suggests that symmetry, induced by shoe lift applied to the paretic limb, could help correct abnormal posture that would be caused in standing and prevent development of abnormal muscle tone in subjects with hemiplegia caused by unilateral stroke.

• 서비스연구
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• 제12권4호
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• pp.30-49
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• 2022

최근 COVID-19로 인한 언택트 시대로의 전환이 가속화되고 사람들이 실내에 머무는 시간이 증가함에 따라 개방된 인터넷을 통해서 영화, 방송 프로그램 등 미디어콘텐츠를 제공하는 OTT(Over-The-Top) 서비스 시장이 크게 확대되었으며 이는 디지털 환경과 기기에 익숙한 MZ세대에게 큰 주목을 받고 있다. 본 연구에서는 OTT 서비스의 특성이 국내 MZ세대 이용자의 몰입 및 만족도와 브랜드 충성도에 미치는 영향에 대해 대표적인 OTT 서비스 브랜드 중 하나인 넷플릭스 국내 이용자를 중심으로 살펴보았다. 본 연구를 수행하기 위해 총 216명의 넷플릭스 OTT 서비스를 이용해본 경험이 있는 사람들의 설문 조사 자료를 분석에 활용하여 수립한 가설을 실증적으로 검증하였다. 분석결과, OTT 서비스의 특성 중 콘텐츠 다양성, 편의성, 신뢰성은 몰입에 정(+)의 영향을 미치는 것으로 나타났다. 또한 몰입은 만족도에 정(+)의 영향을 미치고, 만족도는 브랜드 충성도에 정(+)의 영향을 미치는 것으로 나타났다. 그러나 OTT 서비스의 특성 중 추천 서비스는 몰입에 정(+)의 영향을 미치지 않았으며 몰입은 브랜드 충성도에 직접적으로 정(+)의 영향을 미치지 못하고 만족도를 통해서 브랜드 충성도에 정(+)의 영향을 미치는 것을 확인하였다. 본 연구를 통해서 OTT 서비스 관련 산업의 시장 활성화 및 점점 증가하고 있는 OTT 서비스 브랜드들의 MZ세대 소비자들을 위한 마케팅 전략 수립에 기여할 수 있을 것을 기대하며 포스트 코로나 시대에 대비한 실무적인 시사점을 제공하고자 한다.

• 약학회지
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• 제39권4호
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• pp.401-410
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• 1995

Pharmacolinetic profiles of omeprazole enteric coated granules including Ramezole$^\circledR$, Losec$^\circledR$, omeprazole-Na and omeprazole-resin salt were studied using the crossover design in rats and rabbits. The absorption variance of the preparations at the altered pH condition of the gastrointestinal tract was also studied. After oral administration of four omeprazole enteric coated pellets (10mg/kg) with and without concomitant administration NaHCO$_{3}$ (5 mg/ml, 60 mM) in the rats, the differences of absorplion rate and extent were evaluated. In the NaHCO$_{3}$, administration group, the T$_{max}$ appeared to be 2~10 times shorter than water administration group, and the $C_{max}$ also increased to about 4 times, and the AUC increased to about 2.5 times. Pharmacokinetic parameters of four omeprazole enteric coated pellets in rats showed no statistical significance (ANOVA, P>0.05) in both groups. In the crossover study, the second dosed drug showed 4~5 times increased bioavailability than first dosed drug, which shows the strong carry-over effect of acid secretion of the first dosed drug. The differences of the pharmacokinetic parameters of the two test formulations (Losec$^\circledR$ and omeprazole-resin) showed no statistical significance.

• 대한교통학회지
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• 제12권4호
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• pp.35-52
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• 1994

In order to operate the computerized traffic signal system, it requires the detectors which ensure the exact detections of actual traffic data (e.g., traffic volume, occupancy and velocity of vehicles). The octagonal detectors are used currently in Korea. However, the maintenance of the detectors has many problems with the road repairs and the constructions on the pavement, and failure due to the disconnection of the wires. Serious delay due to the long installation time of loops also causes the traffic disturbances. The low sensitivities and splash-over effect can sometimes create error data after installation of the octagonal loops. The mai purpose of this study is to evaluate the feasibility of domestic use of the round (circular) inductive loops which developed recently in U.S.A. It was found that the round loops are comparable to the existing octagonal loops. In addition, the use of the high quality of materials in the round loop system can reduce the current problems and weakpoints of the octagonal loops. The installation cost of the round loop was found out as economic as the octagonal loop. The installation time of the round loop system can be reduced with the specially equipped loop truck, and wide/deep slots without sharp corners can extend the durability without serious stress of loop head wires. In conclusion, the round loop is superior to the octagonal type in overall points. It is recommended that the localization of the materials and equipments of round loop system is required to carry out the extensive local installations. Also, several contractors to meet the nationwide demand should be arranged to gurantee the proper maintenance and operation of the systems.

• 산업경영시스템학회지
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• 제43권3호
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• pp.41-52
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• 2020

This paper investigates the stress-reducing preventive maintenance model through numerical experiments. The preventive maintenance model is used to analyze the relationship between related conditions and variables to gain insight into the efficient operation of the system when performing preventive maintenance in real-world situations. Various preventive maintenance models have been developed over the past decades and their complexity has increased in recent years. Increasing complexity is essential to reflect reality, but recent models can only be interpreted through numerical experiments. The stress-reducing preventive maintenance is a newly introduced preventive maintenance concept and can only be interpreted numerically due to its complexity, and has received little attention because the concept is unfamiliar. Therefore, for information purposes, this paper investigates the characteristics of the stress-reducing preventive maintenance and the relationship between parameters and variables through numerical experiments. In particular, this paper is focusing on the economic feasibility of stress-reducing preventive maintenance by observing changes in the optimal preventive maintenance period in response to changes in environmental stress and the improvement factor. As a result, when either the environmental stress or the improve effect of stress-reducing preventive maintenance is low, it is not necessary to carry out the stress-reducing preventive maintenance at excessive cost. In addition, it was found that the age reduction model is more economical than the failure rate reduction model.

• Corrosion Science and Technology
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• 제9권6호
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• pp.317-324
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• 2010

Marine transportation by ships is characterized by remote, large-volume and lower rates than the others carry system. Ships account for over 80% of all international trading, and marine transportation is an internationally competitive, strategic, and great national important industry. The construction of larger and faster ships has brought about many problems such as cavitations and erosion corrosion. Cavitations and erosion corrosion make damages on materials and leads to break down members due to continuous physical contacts with shock waves and fluids from the generation and extinction of air bubbles in sea water vortex. The steel used for ship constructions was spray-coated with Al wire, and additionally sealed with fluorine silicone sealing material. Results of experiment, corrosion resistance of sealed thermal spray coating was improved, however in cavitation resistance, the large effect was not appeared. Accordingly, this study applied for thermal spray coating to provide better electrochemical characteristics and corrosion resistance in marine environment.

• Asia Marketing Journal
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• 제18권4호
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• pp.125-138
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• 2017

The goal of the study is to understand how consumers' constraint as opposed to utility structure gives rise to final decision when consumers purchase more than one variant of product at a time, i.e., horizontal variety seeking or multiple-discreteness. Purchase and consumption decision not only produces utility but also involves some sort of cognitive pressure. Past consumption or last purchase is likely to be linked to this burden we face such as concern for obesity, risk of harm, and guilt for mischief. In this research, the existence and the role of dynamic constraint are investigated through a microeconomic utility model with multiple dynamic constraint. The model is applied to the salty snacks data collected from field study where burden for spiciness serves as a constraint. The results are compared to the conventional multiple discreteness choice models of static constraints, and policy implications on price discounts is explored. The major findings are that first, one would underestimate the level of consumer preference for product offerings when ignoring the carry-over of the concern from the past consumption, and second, the impact of price promotion on demand would be properly evaluated when the model allows for the role of constraint as both multiple and dynamic. The current study is different from the existing studies in two ways. First, it captures the effect of 'mental constraint' on demand in formal economic model. Second, unlike the state dependence well documented in the literature, the study proposes the notion of state dependence in different way, via constraint rather than utility.