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A Study on IPA-based Competitiveness Enhancement Measures for Regular Freight Service (IPA분석을 이용한 정기화물운송업의 경쟁력 강화방안에 관한 연구)

  • Lee, Young-Jae;Park, Soo-Hong;Sun, Il-Suck
    • Journal of Distribution Science
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    • v.13 no.1
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    • pp.83-91
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    • 2015
  • Purpose - Despite the structural irrationality of multi-level transportation and the oil price rise, the domestic freight transportation market continues to grow, mirroring the rise in e-commerce and resultant increase in courier services and freight volumes. Several studies on courier services have been conducted. However, few studies or statistics have been published regarding regular freight services although they have played a role in the freight service market. The present study identifies the characteristics of regular freight service users to seek competitiveness enhancement measures specific to regular freight services. Research design, data, and methodology - IPA is a comparative analysis of the relative importance of and satisfaction with each attribute simultaneously. This study used IPA because it facilitates the process of analyzing importance and performance, deriving implications and a visual understanding of results. To enhance the competitiveness of regular freight services, this study surveyed its current users regarding the importance of the regular freight service factors. A total of 200 copies of a questionnaire were circulated and 190 copies were returned. In addition to demographics, respondents answered questions about the importance of and satisfaction with services on a 5-point Likert scale. Excluding 3 inappropriate copies, 187 out of 190 copies were analyzed. PASW Statistics 18 was used for statistical analysis. A total of 20 question items were selected for the service factors presented in the questionnaire based on the 1st pilot survey and previous studies. Results - According to the IPA performed to compare the importance of and satisfaction with service factors, both importance and satisfaction are high in the 1st quadrant, which involves the economic advantage of using regular freight services, quick arrival at destinations, weight freight handling, and less time constraints on freight receipt/dispatch. This area requires continuous management. Satisfaction is higher than importance in the 2nd quadrant, which involves the adequacy of freight, cost savings over ordinary courier services, notification on freight arrival, and freight tracking information. This area requires intensive investment and management. Satisfaction is lower than importance in the 3rd quadrant, involving the credit card payment system, courier delivery service, distance to freight handling sites, easy access to freight handling sites, and prompt problem solving. This area requires further intensive management. Both importance and satisfaction are low in the 4th quadrant, involving the availability of collection service, storage space at freight handling sites, kindness of collection/delivery staff, kindness of outlet staff, and easy delivery checks. This area is a set of variables should be excluded from priority control targets. Conclusions - Based on the IPA, service factors that need priority controls because of high importance and low satisfaction include the credit card payment system, delivery service, distance to freight handling sites, easy access to freight handling sites, and prompt problem solving. The findings need to be applied to future marketing strategies for regular freight services and for developing competitiveness enhancement programs.

Bioequivalence Test of Gabapentin 400 mg Capsules (가바펜틴 400밀리그람 캡슐의 생물학적동등성시험)

  • Kim, Se-Mi;Kang, Hyun-Ah;Cho, Hea-Young;Shin, Sae-Byeok;Yoo, Hee-Doo;Yoon, Hwa;Lee, Yong-Bok
    • YAKHAK HOEJI
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    • v.52 no.3
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    • pp.195-200
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    • 2008
  • Gabapentin, [1-(aminomethyl) cyclohexaneacetic acid], a structural analog of $\gamma$-aminobutyric acid (GABA), is being developed for the treatment of epilepsy. Unlike GABA, gabapentin crosses the blood-brain barrier after systemic administration. Gabapentin is an effective antiepileptic drug in patients with partial and secondarily generalized seizures who are uncontrolled with use of existing anticonvulsant drug therapy. The purpose of the present study was to evaluate the bioequivalence of two gabapentin 400 mg capsules, $Neurontin^{(R)}$ capsule 400 mg (Pfizer Inc.) and Gabatin capsule 400 mg (Korean Drug Co. Ltd), according to the guidelines of the Korea Food and Drug Administration (KFDA). The release of gabapentin from the two gabapentin formulations in vitro was tested using KP VIII Apparatus II method with various dissolution media (pH 1.2, 4.0, 6.8 buffer solution and water). Twenty six healthy male subjects, 23.58$\pm$1.50 years in age and 66.74$\pm$8.31 kg in body weight, were divided into two groups and a randomized 2$\times$2 cross-over study was employed. After one capsule containing 400 mg as gabapentin were orally administered, blood was taken at predetermined time intervals and the concentrations of gabapentin in serum were determined using HPLC with fluorescence detector. The dissolution profiles of two formulations were similar at all dissolution media. In addition, the pharmacokinetic parameters such as $AUC_t$, $C_{max}$ and $T_{max}$ were calculated and ANOVA test was utilized for the statistical analysis of the parameters using logarithmically transformed $AUC_t$, $C_{max}$ and untransformed $T_{max}$. The results showed that the differences between two formulations based on the reference drug, $Neurontin^{(R)}$ capsule 400 mg, were 2.04, -3.68 and 16.79% for $AUC_t$, $C_{max}$ and $T_{max}$, respectively. There were no sequence effects between two formulations in these parameters. The 90% confidence intervals using logarithmically transformed data were within the acceptance range of log 0.8 to log 1.25 (e.g., log 0.91$\sim$log 1.16 and log 0.87$\sim$log 1.11 for $AUC_t$ and $C_{max}$, respectively). Thus, the criteria of the KFDA bioequivalence guideline were satisfied, indicating Gabatin capsule 400 mg was bioequivalent to $Neurontin^{(R)}$ capsule 400 mg.

Preparation and Characterization of PLGA Scaffold Impregnated Keratin for Tissue Engineering Application (케라틴이 함유된 조직공학적 PLGA 지지체의 제조 및 특성 분석)

  • Oh, A-Young;Kim, Soon-Hee;Lee, Sang-Jin;Yoo, James J.;Dyke, Mark van;Rhee, John M.;Khang, Gil-Son
    • Polymer(Korea)
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    • v.32 no.5
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    • pp.403-408
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    • 2008
  • Keratin is the major structural fibrous protein providing outer covering such as wool, hair, and nail. Keratin is useful as natural protein. We developed the keratin loaded poly(L-lactide-co-glycolide) (PLGA) scaffolds (keratin/PLGA) for the possibility of the application of the tissue engineering using bone marrow mesenchymal (BMSCs). Keratin/PLGA (contents 0%, 10%, 20% and 50% of PLGA weight) scaffolds were prepared by solvent casting/salt leaching method. We characterized porosity, wettability, and water uptake ability, DSC of keratin/PLGA scaffold. We seeded BMSCs isolated from the femurs of rat into the inner core of the hybrid scaffold. Celluar viability were assayed by 3- (4,5-dimethylthiazol-2-yl) -2,5-diphenyl-tetrazolium bromide (MTT) test. We confirmed that keratin/PLGA scaffold is hydrophilic by wettability, and water uptake ability measurement results. In MTT assay results, cell viability in scaffolds impregnated 10 and 20 wt% of keratin were higher than other scaffolds. In conclusion, we suggest that keratin/PLGA scaffold may be useful to tissue engineering using BMSCs.

Prediction Model of Flexural Properties of LEFC using Foaming Agent (기포제 적용 빛 감성 친화형 콘크리트의 휨 특성 예측 모델)

  • Kim, Byoung-Il;Seo, Seung-Hoon
    • Journal of the Korea Institute of Building Construction
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    • v.19 no.1
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    • pp.9-18
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    • 2019
  • Concrete, which is the most widely used building material in modern times, has been improved not only in strength but also in structural performance such as increase in toughness and ductility, weight reduction, and improvement in quality of human life. Due to the surge in demand for the building, there is a tendency to be used variously from architectural panel and architecture to interior accessories. In Korea, a light-transmitting concrete, LEFC(Light Emotion Friendly Concrete), that insert plastic rods to stimulate emotional sensation through the combination of light and concrete has developed. In previous research, it was confirmed that the use of a synthetic foam agent rather than an animal foam agent did not cause a fogging phenomenon. In this study, lightweight by applying foaming agent to LEFC and two types of fiber (Nylon Fiber, Polyvinyl Alcohol) were compared to achieve to investigate the fiber to be applied in future. An equation that can predict the loss and adhesion reduction of the concrete section according to the diameter of the rod (5mm, 10mm) and the interval (10mm, 15mm, 20mm) was proposed.

The Evaluation of flexure performance of SCP modules for LNG outer tank (LNG 외조탱크 적용을 위한 SCP 모듈의 휨성능 평가)

  • Park, Jung-Jun;Park, Gi-Joon;Kim, Sung-Wook;Kim, Eon;Shin, Dongkyu
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.1
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    • pp.447-455
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    • 2019
  • When constructing LNG storage structures using the cast-in-place method in extreme areas, the construction cost and time may be increased due to the poor working environments and conditions. Therefore, demand for modular energy storage tanks is increasing. In this study, we propose using an SCP module as an alternative for lighter-weight LNG storage tanks. The purpose of this study is to evaluate the feasibility of LNG storage outer tanks by performing bending tests on the thickness of composite steel plate concrete under field conditions. The loads on specimens with thicknesses of 100 mm and 200 mm were linearly increased to the design final loads of 413 kN and 822 kN, respectively. The slope was rapidly changed, and fracture occurred. The two test conditions showed linear behavior until the steel plate yielded, and after an extreme load behavior, sudden yielding of the steel plate yield occurred in the SCP bending test according to the INCA guidelines. The results satisfied the design flexural load and showed the possibility of using the specimens in a modular LNG outer tank. However, it is necessary to evaluate the structural performance of the SCP by performing compression and shear tests in future research.

A Development of Representative Condition Evaluation Standard for LNG Storage Tank Structures (LNG 저장탱크 구조물의 종합적 상태평가기준 개발)

  • Kim, Jung-Hoon;Jo, Young-Do
    • Journal of the Korean Institute of Gas
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    • v.22 no.6
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    • pp.44-51
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    • 2018
  • As the LNG storage tank is aged, if there is a crack in the outer wall concrete or corrosion of the reinforcing steel, there is a risk of a major accident such as collapse of the structure depending on the type and degree of damage. Since 2014, LNG storage tanks have undergone precise safety diagnosis and safety inspection has been carried out. The condition evaluation criteria for each component have been revised and applied in January 2016. The condition evaluation standard is to evaluate the status of storage tanks based on the appearance survey and material test results of LNG storage tanks and it is important for maintenance. In addition, the representative condition evaluation standard that shows the comprehensive state of each LNG storage tank is important in maintenance, but the related standard for LNG storage tank outer concrete is not available in Korea and abroad, and development of the condition evaluation standard is necessary. In this paper, we examined the structural characteristics of LNG storage tanks, analyzed the status of the condition evaluation criteria for each member, and developed a comprehensive status rating system by weighting the members. We used the AHP(Analytic Hierarchy Process) technique and developed a representative conditon evaluation criteria through surveys of professional organizations.

Development of Lightweight Composite Sub-frame in Automotive Chassis Parts Considering Structure & NVH Performance (구조 및 NVH 성능을 고려한 복합재료 서브프레임 개발)

  • Han, Doo-Heun;Ha, Sung
    • Composites Research
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    • v.32 no.1
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    • pp.21-28
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    • 2019
  • Recently, according to environmental regulations, the automobile industry has been conducting various research on the use of composite materials to increase fuel efficiency. However, there has not been much research on lightweight chassis components. Therefore, in this research, the purpose of this study is to apply composite materials to the sub-frame of chassis components to achieve equivalent levels of stiffness, strength, NVH performance and 50% lightweight compared to the steel sub-frame. First, the Natural frequency of steel and composite specimens was compared to the damping characteristics of composite materials. Then, in this study, the Lay-up Sequence was derived to maximize the stiffness and strength of the sub-frame by applying composite materials. And this lay-up Sequence is proposed to avoid heat shrinkage due to curing during manufacturing. This process was designed based on a FEM structural analysis, and a Natural frequency and frequency response function graph was confirmed based on a modal analysis. The prototype type composite sub-frame was manufactured based on the design and the F.E.M analysis was verified through a modal experiment. Furthermore, it was fitted to the actual vehicle to verify the natural frequency and the indoor noise vibration response, including idling and road noise. This result was confirmed to be equivalent to the steel sub-frame. Finally, the composite sub-frame weight was confirmed to be about 50% of the steel sub-frame.

Experimental Assessment and Specimen Height Effect in Frost Heave Testing Apparatus (동상시험장비의 실험적 검증 및 시료크기의 영향에 관한 연구)

  • Jin, Hyunwoo;Ryu, Byunghyun;Lee, Jangguen
    • Journal of the Korean GEO-environmental Society
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    • v.20 no.1
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    • pp.67-74
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    • 2019
  • Frost heave is one of the representative engineering characteristics in cold regions. In South Korea, which is located in seasonal frost area, structural damage caused by frost heave and thaw happens and the need for research on the frost heave is increasing. In this paper, newly developed transparent temperature-controllable cell is used to focus on the frost heave. Frost susceptible artificial soil is used to analyze water intake rate which is one of the important factors in frost susceptibility criteria. Frost heave rate and water intake rate have similar behavior after heave by freezing of pore water converges. O-ring installed in the upper pedestal to measure water intake rate generates side friction between the inner wall of the freezing cell and O-ring, thereby hindering frost heave. Therefore, the frost susceptibility criteria using the water intake rate is not reliable. It is appropriate to use frost heave rate which has similar behavior with water intake rate. Frost heave tests were performed under two different specimen heights. Overburden pressure, temperature gradient and dry unit weight were set under similar state. Based on laboratory testing results, frost heave is independent on the specimen height.

The Effect of Low Molecule Collagen Peptide on Skin Anti-glycation and Collagen Synthesis as a Skin Aging Therapy (피부 노화 치료로서 저분자콜라겐펩타이드의 피부 항당화와 콜라겐 합성 효과)

  • Kim, Hong Seok;Hong, Won Kyu;Lee, Mun Hoe;Kim, Hyeong Min;Chung, Hee Chul;Lee, Jin Hee
    • Journal of the Society of Cosmetic Scientists of Korea
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    • v.47 no.2
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    • pp.147-153
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    • 2021
  • Collagen hydrolysate (CH) is known to prevent skin aging by stimulating skin dermal fibroblasts to promote synthesis of extracellular matrix such as collagen and elastin. Recently, among the various factors that cause skin aging, advanced glycation end products (AGEs) have received particular attention. However, the effect of CH on AGE accumulation has not been studied. Since CH could affect AGE accumulation by promoting production of skin structural proteins, clinical trial was performed using low molecule collagen peptide (LMCP), which were CH containing 25% tripeptide and 4% Gly-Pro-Hyp. Skin autofluorescence (SAF) values were measured using an AGE reader to evaluate accumulation of AGE in skin. As a result of applying 0.5% and 1.0% LMCP solutions to the subject's forearm for 8 weeks, the SAF value at the test site significantly decreased compared to the control site. Additionally, in vitro test was performed using CCD-986sk to evaluate the promotion of collagen synthesis in skin fibroblasts by LMCP. As a result, 800 ㎍/mL of LMCP significantly increased synthesis of human pro-collagen Iα1 (COL1A1) in CCD-986sk. Through this study, we have confirmed that tropical LMCP applications can promote collagen synthesis to help anti-glycation effects, suggesting that LMCP has potential as an anti-aging cosmetic material.

Development of a Silicon Carbide Large-aperture Optical Telescope for a Satellite (SiC를 이용한 대구경 위성용 망원경 제작)

  • Bae, Jong In;Lee, Haeng Bok;Kim, Jeong Won;Lee, Kyung Mook;Kim, Myung-Whun
    • Korean Journal of Optics and Photonics
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    • v.33 no.2
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    • pp.74-83
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    • 2022
  • The entire process, from the raw material to the final system qualification test, has been developed to fabricate a large-diameter, lightweight reflective-telescope system for a satellite observation. The telescope with 3 anastigmatic mirrors has an aperture of 700 mm and a total mass of 66 kg. We baked a silicon carbide substrate body from a carbon preform using a reaction sintering method, and tested the structural and chemical properties, surface conditions, and crystal structure of the body. We developed the polishing and coating methods considering the mechanical and chemical properties of the silicon carbide (SiC) body, and we utilized a chemical-vapor-deposition method to deposit a dense SiC thin film more than 170 ㎛ thick on the mirror's surface, to preserve a highly reflective surface with excellent optical performance. After we made the SiC mirrors, we measured the wave-front error for various optical fields by assembling and aligning three mirrors and support structures. We conducted major space-environment tests for the components and final assembly by temperature-cycling tests and vibration-shock tests, in accordance with the qualifications for the space and launch environment. We confirmed that the final telescope achieves all of the target performance criteria.