• Korean Journal of Metals and Materials
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• v.47 no.9
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• pp.533-541
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• 2009

Materials used for a reactor pressure vessel(RPV) are required high strength and toughness, which determine the safety margin and life of a reactor. Ni-Mo-Cr low alloy steel shows better mechanical properties than existing RPV steels due to higher Ni and Cr contents compared to the existing RPV steels. The present study focuses on effects of Ni, Cr contents on the cleavage fracture toughness of Ni-Mo-Cr low alloy steels in the transition temperature region. The fracture toughness was characterized by a 3-point bend test of precracked Charpy V-notch(PCVN) specimens based on ASTM E1921-08. The test results indicated that the fracture toughness was considerably improved with an increase of Ni and Cr contents. Especially, control of Cr content was more effective in improving fracture toughness than manipulating Ni content, though Charpy impact toughness was changed more extensively by adjusting Ni content. These differences between changes in the fracture toughness and that in the impact toughness were derived from microstructural features, such as martensite lath size and carbide precipitation behavior.

• Journal of the Korea Institute of Information and Communication Engineering
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• v.7 no.1
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• pp.129-135
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• 2003

Optical fiber has many advantages, such as high reliability, long lifetime, immunity to the electromagnetic interference, high speed response and low cost. In this study, we proposed and developed an optical fiber impact and pressure sensor for prevention of accident which occurs in the automatic system or auto door. The principle of the sensor is to detect different optical intensity caused by variation of a speckle pattern due to the external perturbation. Speckle pattern appears at the end of a multimode fiber in which coherent beam propagates. The fabricated sensor in this study was tested. As a result of experiments, amplitude of the output signal isn't linear, but it has sufficient sensitivity for a sensor. Moreover, we can control sensitivity of the sensor by an amplifier at receiver. It has several advantages which are ability of detection at all point on the multimode fiber, large sensitive area, and many application areas for a sensing impact and pressure.

• Journal of the Korean Institute of Landscape Architecture
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• v.18 no.2
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• pp.1-13
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• 1990

In recent years, the construction of golf course has been increasing very rapidIy and serious concern is paid to its environmental consequences both in Korea and in Japan. EIA systems as a major requirements for golf course developments emerged to reduce the adverse impact of their developments in Korea as well as in Japan. This study aims to compare EIA systems, procedures and methodologies employed between Korea and Japan in order to demonstrate the success and failure of EIAs in each country. The results of this study can be summarized as follows : 1) EIAs are systematically undertaken based upon law in Korea but on regulation in Japan. 2) Public participation Isn't encouraged in the Korean EIA procedure while the Japan EIA system involves public participation. 3) Korean EISs shall be prepared after the proposed projects are approved according to the related laws and be followed by the necessary procedures, but in the carte of Japan, EISs be prepared prior to their approval . 4) ELSs shall be prepared by agencies with special expertise with respect to 7he environmental impacts (appointed by government) or the sponsoring agencies themselves in Korea whereas they be prepared by agencies proposing the projects in japan. 5) EISs both in Korea and in Japan are characterized by cliches which may be unfamiliar to reviews and the public. 6) EIAs describe the existing presence and predict and evaluate that a development work influences the present conditions. Here Japan EIA treats mainly natural - and life environment, whereas Korean EIA dose social - and economic environment. And hence in the case of Japan is undertaken more quantitative and scientific analysis, whereas in the case of Korea is less. It is suggested that the key point to impact analysis is to use the correct concepts, fomulate the comparative studies of methodologies and find the methods that suit the decision as well as which country's own circumstances.

• The Journal of Korean Association of Computer Education
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• v.15 no.2
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• pp.75-81
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• 2012

As the number of web users is increasing, the leakage of personal information is increasing. If some personal information is leaked, the victim can suffer from material damage or mental damage at the same time. Most of the leakages are result from the people who works for the personal information by accident or design. Hence, the Ministry of Public Administration and Security proposeed the measuring index and enumerates the details. The index is used in a system to check protection of a personal information. However, because this system is used to evaluate after the leakage, it cannot be used to construct some security system or programming a security system. To solve this problem, it needs to express the diversity of items and be able to count what assessors want to count. Thus, a summary sheet which displays the result of the tool will be presented in a radial form graph. Details will be presented as a bar graph. Therefore, it will be proposed that the tool can grasp the weak point and propose the direction of security.

• Journal of Korean Society of Archives and Records Management
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• v.20 no.4
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• pp.229-236
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• 2020

In light of SARS-CoV-2's significant impact, human society has experienced rapid changes in lifestyle that it has not yet experienced before. One way this virus has influenced people's lives is the emergence of the zero-contact society, an initiative for preventing the spread of infectious diseases. As can be seen, the social impact of COVID-19 is widespread. Various issues, such as those about government policy, personal information protection, and health care, are affecting society as a whole. At the same time, factual information is difficult to track and record because of the rapid and transient nature of related events and issues. As such, a method of effectively describing COVID-19 and real-time information is necessary. The "COVID-19: Our Memory" project is an attempt to record the sociocultural impact of the coronavirus infection. This project collects major events and issues classified into several subjects, records those events from a neutral point of view, and develops a digital archive so that all records are accessible. All the data collected and built through the project, the application, including the source code and visualization, are all published to bring about new opportunities for collaboration.

• Journal of Digital Convergence
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• v.11 no.11
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• pp.603-611
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• 2013

This study examines the impact of job stress on customer-oriented boundary-spanning behavior with the mediating effects of organizational commitment. The survey data was collected from 147 employees working at a hospital and analyzed statistically by using SPSS 18.0 and AMOS 18.0. The result of this study are as follows. Hypothesis 1, Job stress has a negative influence on organizational commitment. Hypothesis 2, Organizational commitment has a positive influence on customer-oriented boundary-spanning behavior. Hypothesis 3, Job stress has a negatively significant impact on customer-oriented boundary-spanning behavior. Accordingly, Organizational commitment has the role of partially mediating the effect between job stress and customer-oriented boundary-spanning behavior. This means that employees working at the point of meeting customers must reduce their job stress in order to improve the service quality of a hospital and creating solutions to reduce job stress of hospital employees can increase customer-oriented boundary-spanning behavior.

• Journal of Korean Society on Water Environment
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• v.34 no.4
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• pp.382-390
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• 2018

In this study, the LIDMOD3 was developed to design and evaluate low impact development (LIDMOD). In the same fashion, the LIDMOD3 employs a curve number (NRCS-CN) method to estimate the surface runoff, infiltration and event mean concentration as applicable to pollutant loads which are based on a daily time step. In these terms, the LIDMOD3 can consider a hydrologic soil group for each land use type LID-BMP, and the applied removal efficiency of the surface runoff and pollutant loads by virtue of the stored capacity, which was calculated by analyzing the recorded water balance. As a result of Model development, the LIDMOD3 is based on an Excel spread sheet and consists of 8 sheets of information data, including: General information, Annual precipitation, Land use, Drainage area, LID-BMPs, Cals-cap, Parameters, and the Results. In addition, the LIDMOD3 can estimate the annual hydrology and annual pollutant loads including surface runoff and infiltration, the LID efficiency of the estimated surface runoff for a design rainfall event, and an analysis of the peak flow and time to peak using a unit hydrolograph for pre-development, post-development without LID, and as calculated with LID. As a result of the model application as applied to an apartment, the LIDMOD3 can estimate LID-BMPs considering a well spatical distributed hydroloic soil group as realized on land use and with the LID-BMPs. Essentially, the LIDMOD3 is a screen level and simple model which is easy to use because it is an Excel based model, as are most parameters in the database. This system can be expected to be widely used at the LID site to collect data within various programmable model parameters for the processing of a detail LID model simulation.

• Journal of the Korean Society for Railway
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• v.10 no.5
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• pp.596-599
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• 2007

A comparative Life Cycle Assessment (LCA) among three types of Electric Motor Unit (EMU) Interior Panel (IP) was conducted. A functional unit for comparative LCA is a weight of IP for 1 EMU. It is assumed that Manufacturing stage and its upstream processes, Use stage and End of Life (EoL) stage are included in the boundary of product system. For Use stage, the weight of IP causes electricity consumption. It is assumed that aluminum IP is recycled and the other IPs are incinerated at the EoL stage. As a comparison results, aluminum IP has much larger environmental impact (5.162pt) than others (FRP IP; 4.069pt, Phenol IP; 4.053pt) even though recycling consideration is included. The manufacturing stage of aluminum IP has relative big environmental impact (1.824pt) and this point make the most important difference from other IPs (FRP IP; 0.1617pt, Phenol IP; 0.4534pt)). Despite of large weight difference between FRP IP (888.96kg) and phenol IP (316kg), the final environmental impact result has only little difference (0.016pt, 0.39%). With this result, the EMU designer can choose IP with a consideration of the environmental performance of IP.

• Journal of Korea Trade
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• v.25 no.1
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• pp.1-17
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• 2021

Purpose - The global trend of protectionism has expanded since the onset of US President Donald Trump's administration in 2017. This global phenomenon has led to a significant reduction in world trade volume and a negative impact on economic development in some countries where the external sector accounts for a large proportion of GDP. Although Korea is a country vulnerable to this deteriorating trade environment, few studies have examined the relationship between protectionism and its business cycles based on Korean data. Thus, this paper investigates the impact of protectionism on Korea's business cycle. Design/methodology - To identify future implications, we conduct a structural vector autoregression (VAR) analysis using monthly Korean data from 1994 to 2015. Macroeconomic variables in the model include the industrial production index, inflation rates, exports (or net exports), interest rates, and exchange rates. For the identification of the shock reflecting the expansion of protectionism, we use an antidumping investigation (ADI) data. Since ADIs are followed generally by the imposition of antidumping tariffs, they have no contemporaneous impact on tariffs and are also contemporaneously exogenous to other endogenous variables in the VAR model. We examine two kinds of ADI shocks i) shocks on Korean exports imposed by Korea's trading partners (ADI-imposed shocks) and ii) shocks on imports imposed by the Korean government (ADI-imposing shocks). Findings - We find that Korea's exports decline sharply due to ADI-imposed shocks; the lowest point at the third month after the initial shock; and do not recover until 24 months later. Simultaneously, the inflation rate decreases. Therefore, the ADI-imposed shock can be regarded as a negative shock on the demand curve where both production and price decrease. In contrast, the ADI-imposing shock generates a different response. The net exports decline, but the inflation rate increases. These can be seen as standard responses with respect to the negative shock on the supply curve. Originality/value - We shed light on the relationship between protectionism and Korea's economic fluctuations, which is rarely addressed in previous studies. We also consider the effects of both protective policy measures on imports to Korea imposed by the Korean government and on policy measures imposed by Korea's trading partner countries on its exports.

• Korean Journal of Labor Studies
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• v.23 no.1
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• pp.197-220
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• 2017

This paper provides empirical evidence on the impact of increasing import penetration on the job stability of Korean workers. The main results are as follows. First, import penetration negatively affects job stability. If an industry's ratio of imports to total supply increases by 1 percentage point, the turnover probability of workers in that industry increases by 4.5 percentage points. Second, the effect of trade liberalization is not symmetric between imports and exports. Unlike the case of imports, an industry's ratio of exports to output does not have a significant effect on job stability. Third, the impact of import penetration is not uniform across different types of workers. The negative impact is greater for workers in small firms, less educated workers, and those not protected by labor unions.