This paper is concerned with a test method that can be used to investigate the parameters of the Johnson-Cook constitutive model. These parameters are essential for accurately analyzing material behavior under impact loading conditions in numerical simulation. Ti-6Al-4V alloy (HCP crytal structure) was used as a specimen for the experiments. In the 10−3-103/ s strain rate range, three types of experimental methods (convention, compression and tension) were employed to compare the differences using MTS-810, SHPB and SHTB. Finite element analysis results when applying these parameters were displayed along with the experiment results.

Columns in existing reinforced concrete structures that are designed and constructed without considering seismic loads generally exhibit widely spaced transverse reinforcements without using seismic hooks. Due to the insufficient reinforcement details in columns compared to the reinforcement requirements specified in modern seismic codes, brittle shear failure is likely to occur. This may lead to sudden collapse of entire structure during earthquakes. Adequate retrofit strategy is required for these columns to avoid such catastrophic event. In order to do so, behavior of columns in existing reinforced concrete structures should be accurately predicted through computational analysis. In this study, an analytical model is proposed for accurately simulating the cyclic behavior of shear critical columns. The parameters for backbone, as well as pinching and cyclic deterioration in strength and stiffness are calibrated using test data of column specimens failed by shear.

The sol-gel method is the simplest method for synthesizing monodispersed silica particles. The purpose of this study is to synthesize uniform, monodisperse spherical silica nanoparticles using tetraethylorthosilicate (TEOS) as the silica precursor, ethanol, and deionized water in the presence of ammonia as a catalyst. The reaction time and temperature and the concentration of the reactants are controlled to investigate the effect of the reaction parameters on the size of the synthesized particles. The size and morphology of the obtained silica particles are investigated using transmission electron microscopy and particle size analysis. The results show that monodispersed silica particles over a size range of 54-504 nm are successfully synthesized by the sol-gel method without using any additional process. The nanosized silica particles can be synthesized at higher TEOS/H2O ratios, lower ammonia concentrations, and especially, higher reaction temperatures.

본 연구의 목적은 시스템 식별기술과 칼만필터링을 기반으로 계측된 가속도응답을 이용하여 구조물에 작용하는 모달하중을 역으로 추정하는 기법을 제시하는데 있다. 하중추정 과정에서 가속도응답은 모드응답으로 분해되며 각 모드응답에 대한 모달하중을 역으로 추정한다. 역해석과정에서 발생하는 ill-posed문제를 피하기 위하여 가상진동기에 의해 구조물의 고유진동수와 감쇠비를 보다 정밀하게 구하기 위한 시스템 식별법을 사용하였다. 본 연구에서 제안된 기법의 적용성을 위하여 40층의 철골구조물에 태풍이 작용 했을 때 계측된 가속도를 사용하였다. 적용결과에 의하면 본 연구에서 제안된 하중추정법에 의하여 모달하중 추정이 가능함을 알 수 있었다.

Service industry can be divided largely into commercial industry, banking industry, insurance industry, advertising industry, and tourism industry. Of these, banking industry is playing an essential role as it constitutes the backbone of economy. Banking industry, which belongs to financial industry, is sensitive to external environment. In this kind of industry, internal dynamics of an organization is very important. The purpose of this research is to find out what kind of influence the relation of internal dynamics perceived by members of Nonghyup organization has on customer orientation via quality of internal service. For the purpose, we have reviewed preceding studies on variables that affect customer orientation and developed a measuring tool in a form that fits banking organizations. Internal service quality, job satisfaction, and organizational immersion which play a mediating role in the model of this research not only turned out to have a significant influence on customer orientation, they also turned out to have the strongest influence. This research has academic significance as it carried out a research with an emphasis on variables that affect customer orientation of members of Nonghyup organization. Regarding practical significance, it was intended to present useful data that can be utilized for an analysis of internal service quality management and capability of human resource management.

PVDF Membrane has been used as material for the UF membrane through in-situ interfacial polymerization (IP) because of it’s outstanding properties such as high chemical resistance, thermal stability, and mechanical strength. In this study, surface morphology change of PVDF membrane was researched depending on evaporation time. 13% PVDF 6020 was used for casting and the evaporation time period was from 5s to 600s. The surface morphology of the membrane was investigated by scanning electron microscopy (SEM) and filtration was conducted in the cross flow method to evaluate the a performance of UF membrane. As a result, average pore size was increased with longer evaporation times which caused the decrease of rejection.

The thermally induced phase separation(TIPS) method offers higher reproducibility with lower tendency for defect formation and narrower pore size distribution, rendering the method more suitable for microfiltration(MF) and ultrafiltration(UF) applications. PVDF is widely used in membrane technology due to their excellent chemical resistance and strong mechanical properties. In case of MF and UF applications, the stretching method has been applied for increasing the performance of membrane by extending pore size. In this work, the effects of dope and bore flow rates and dope composition on the tensile strength of membranes was investigated. A design of experiment(DOE) analysis was used to understand the effects of the stretching parameters such as temperature, stretching ratio and holding time on the membrane performance.

The objective of this study was to determine the effect of drinking water containing trimethyl glycine or ascorbic acid on growth performance and blood parameter profiles of duck exposed to scorching heat stress. A total of 480 ducks were randomly assigned to the following eight experiment groups for 42 days : control group C with general water, treatment group 1 (T1) with drinking water containing 100 ppm ascorbic acid, treatment group 2 (T2) with drinking water containing 200 ppm ascorbic acid, treatment group 3 (T3) with drinking water containing 300 ppm ascorbic acid, treatment group 4 (T4) with drinking water containing 400 ppm trimethyl glycine, treatment group 5 (T5) with drinking water containing 800 ppm trimethyl glycine, treatment group 6 (T6) with drinking water containing 1,200 ppm trimethyl glycine, treatment group 7 (T7) with electrolytes of KCl (0.5%) + NaHCO3 (1.0%)+NaCl (0.5%). Our results revealed that the body weights and feed intakes of treatment groups, especially T3 and T6, were increased compared to the control group, where as the feed conversion ratios of treatment groups were decreased (p<0.05). Blood levels of total cholesterol, triglyceride, LDL-C, glucose, AST, ALT and pH in treatment groups were lower compared to those in the control group (p<0.05). Blood levels of red blood cell, platelets profiles, electrolyte and gas in treatment groups were higher compared to those of the control group (p<0.05).

The organization which is does sale activity in 21c, face a radical environment changes and high competition. To overcome from these situation, employee who is does sale in field are important to set sustainablity to the organization. A sales person is one of member in organizations, so they have a relation with other employee in process of job. To increase there performance and satisfaction, LMX is focused by many researchers. LMX can increase job satisfaction which can increase job performance thought organizational justice. And career of employee can has moderate effect between LMX and organizational justice. To figure out casual relationship among factors, researcher conduct a empirical analysis use 210 samples from SME saleman. Result of empirical study show us every hypothesis which researcher set up has supported. Based on this result, reseacher provide manageric implications and conclusions

The purpose of this study is to understand how to affect the safety behavior to the organization's trustees to investigate the level of safety awareness, safety awareness via the distribution center workers prepare the logistics industry disaster prevention measures. The survey was analyzed data to target by the clothing distribution center employees of 182 people. Analysis First, the level of safety awareness showed on a positive effect on organization trust. Second, it was found on the safety level of consciousness a positive effect on the safety behavior. Third, the level of safety awareness affect the safety behavior showed that the mediating role of organization trust. That is a higher level of safety awareness, such as the strict practice of business activities, investments, safety rules on safety education and training emphasis on safety increases confidence in the organization. It was confirmed the higher the confidence in the safety organization appears behavior such as actively participating in the work carried out in a safe manner, safety education and training. In addition, the effect was mediated by the organizational impact on confidence in the safety of personnel safety awareness actions. Based on that research results prepared safety awareness was raised through the industrial accident prevention measures

This study investigates on the tuning stainless steel(STS630) to understand for groove cutting characteristics. For this purpose, we observed the cutting force according to feed rate and cutting speed variation and performed the computational analysis due to groove cutting depth. In groove cutting of stainless steel, there were principal force, feed force and radial force by arranging the highest cutting force in order. In case of wall thicknesses of 0.3mm and 0.5mm at groove cutting, principal force increases according to the increase of feed rate but it is not related to cutting speed. We found the unstable region of cutting force that is caused to the friction resistance of cutting tool and elastic deformation of groove wall. In computational analysis, we confirmed that the more feed rate increases, the more strain increases around the tooth root.

We developed an Al sputtering process by varying the plasma power, process temperature, and film thickness. We observed an increase of hillock distribution and average diameter with increasing plasma power, process temperature, and film thickness. Since the roughness of a film increases with the increase of the distribution and average size of hillocks, the control of hillock formation is a key factor in the reduction of Al corrosion. We observed the lowest hillock formation at 30 W and 100 oC. This growth characteristic of sputtered Al thin films will be useful for the reduction of Al corrosion in the future of the electronic packaging field.

The present study investigated the effects of processing parameters such as time (10, 20, 30, 40 min), pressure (25, 50, 75, 100 MPa), and the salinity of brine (0~10%(w/v)) on jacopever (Sebastes schlegeli Hilgendorf) in order to establish optimization of the three factors using a high hydrostatic pressure (HHP) machine. To do so, it analyzed the quality characteristics of volatile basic nitrogen (VBN), trimethylamine (TMA), total bacterial counts, dynamic viscoelasticities, and differential scanning calorimetry (DSC) properties. First, when the time increased to 40 mins, by 10 min intervals, the total bacterial counts in HHP groups under 25℃, 100 MPa, and 4%(w/v) brine were significantly decreased except for the first 10 min in comparison to the control group. In regards to DSC properties, the onset temperature (TO) of the first endothermal curve was significantly reduced. Second, when the pressure level increased up to 100 MPa by 25 MPa increments, the total bacterial counts in the HHP samples significantly decreased for 20 min at 50 MPa or higher. As the pressure increased, G′, G″ and the slope of tan δ decreased (except for 50 MPa). Third, in regards to the salinities of brine, when the HHP processing was treated at 100 MPa, 25℃ for 20 min, the total bacterial counts of all the HHP groups significantly decreased in comparison to those of the control group. A significant difference was found in the enthalpy of the second endothermic curve in the 6~10%(w/v) (except 7%(w/v)) HHP groups. Therefore, the salinity of the immersion water under the HHP condition was appropriate when it was lower than 6%(w/v). The present study demonstrated that the optimum parameter condition according to/under the condition of the microbial inhibition and economic effects using an HHP would be the reaction time for 20 min, reaction pressure at 100 MPa, and the salinity of 4%(w/v) brine.

Bhark Gwang-gyu. 2016. “A Study on Singaporean's Discourse Markers: The case of hor, meh, lah”. The Sociolinguistic Journal of Korea 24(1). 115~147. This study aims to show the characteristic and use aspect of Singaporean's discourse markers such as ‘hor, mah, lah'. This study analyzes features in each type based on gender, generation, occupation, religion, race, educational background through an internet questionnaire survey. The conclusion is presented below. First, Singaporean's discourse markers are used at end of the sentences. Second, Singaporean's discourse markers and Chinese discourse marker(‘哈[ha]’) are used not only oral conversation but also in written conversation. Third, the ‘哈[ha]’ which lexicon is used as discourse marker by chinese in china is grammatized. Forth, There are not much differences based on occupation, race, educational background in the use of discourse makers. However women use discourse markers more than men and young generation use discourse markers more than old generation. Also the buddhist were found to use discourse markers more than the christian and the Roman catholic.

곤충 발육기간분포모형은 어느 특정발육단계가 완료되는 시기의 변이를 나타내는 것으로 시간에 따라 발육이 완료되는 개체들의 비율로 나타낸다. 개체군 모형 작성시 발육단계전이모형의 기본 구성요소로 사용되며, 발육기간 누적빈도분포 자료를 Weibull 함수에 적용시켜 사용하고 있다. 곤충 발육기간분포모형을 추정하려면 발육실험의 원자료가 필요하기 때문에 원자료가 없는 경우 대체할 수 있는 방법의 개발이 필요하다. 따라서 본 연구에서는 곤충의 발육기간 빈도분포가 정규분포를 따른다는 가정 하에 해당 곤충의 발육기간 평균 및 표준편차를 이용하여 가상의 발육기간 빈도분포를 조성하고 매개변수를 추정하는 방법을 제시하였다. 정규분포에 준한 발육기간 누적빈도분포로 Weibull 함수의 모형 매개변수를 추정하고, 이것을 실제 발육기간 빈도분포를 이용하여 추정한 모형 매개변수와 비교하였다. 총 8종 (18개 발육단계) 곤충을 대상으로 분석한 결과 곤충 발육기간 빈도분포가 정규분포를 따르지 않음에 따라 원자료 값과 편차가 발생하였다. 일부 매개변수를 보정함으로써 원자료 값에 가깝도록 조절 할 수 있었으며, 이 방법을 통해 어떤 곤충의 발육기간 빈도분포자료 없이도 발육기간 평균과 표준편차만을 이용하여 발육기간분포모형을 추정할 수 있을 것으로 기대되었다.

The integrative approach for ecological stream health assessments was applied to a stream ecosystem using a multi-level organization from molecular level of biomarkers to community levels of bioindicators along with analysis of physical and chemical stressors. Water quality parameters of BOD, COD, TN, and TP etc were measured and physical habitat health, based on Qualitative habitat Evaluation Index (QHEI) model were analyzed. Also, Ecological stream health model, based on index of biological integrity (IBI) by fish assemblage, was developed for regional assessments and then applied to the stream. Six metric attributes of original 11 metrics were modified for a development of the model. Biomarkers of comet assay, blood chemistry, physiological parameters, and bioindicators such as organismal-, population-, community- level parameters were evaluated in this study along with eco-toxicity tests. Some stations impaired (stressed) in terms of stream health were identified by the IBI approach and also major key stressors affecting the health were identified using BOD, TN, TP, physical habitat evaluation, and eco-toxicity tests. The assessment approach of integrative ecological stream health would be used as a key tool for ecological restorations and species conservations in the degraded stream ecosystems and applied for elucidating major causes of ecological disturbances. Ultimately, this approach provides us an effective management strategy of stream ecosystems through establishments of ecological networks in various watersheds. This research was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education (No. 2013R1A1A4A01012939).

This paper presents the approach of design parameters optimization based on Taguchi method for the uniformity of outlet pressure in a plasma discharge chamber. The key issue of a plasma discharge chamber is to have the uniformity of outlet pressure which can make a high performance of surface treatment. To extend the length of a outlet from 60mm to 250mm with the uniformity, This study optimally designed the middle holes, outlet width and height, and diameter of the second chamber by using SolidWorks and flow simulation tool. Simulation results demonstrate the validity of the proposed approach.