• Korean Journal of Construction Engineering and Management
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• v.11 no.6
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• pp.111-121
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• 2010

As the customer's interest for sidewalk block in the street or apartment complex is increasing, the materials of block which had been a concrete block exclusively are varied to clay paver, native rock and wood etc. Especially, the sales volume of clay paver which is environment-friendly and ergonomic is dramatically increasing every year with two digits growth rate, however, many problems like "Edge Cracking" "Freezing Breakage" "Bending Breakage" "Joint Gap" are happening frequently within a couple of hours after installation due to the durabilities. Because of the characteristics of Ceramic products, clay pavers are very easy to be broken when they are bumped against each other. In addition, they are relatively fragile by a freezing expansion breakage when exposed to water due to hydrophilic property as well as the intensity and absorptance of the products are varied with small difference from the production process such as production equipment and process control. Therefore, it costs a lot of money to repair the breakdown unless production and installation is carried out according to the strict criteria of the quality control. In this study, the symptoms of breakdown frequently happened in clay paver are classified by each type and finally the solution for this problem in the production of brick, installation and criteria of quality control through compressive strength and absorptance test is suggested.

• Journal of the Korean Society for Nondestructive Testing
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• v.26 no.5
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• pp.306-314
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• 2006

Instrumented indentation technique is a new way to evaluate nondestructive such mechanical properties as flow properties, residual stress and fracture toughness by analyzing indentation load-depth curves. This study evaluated quantitatively the flow properties of steels and residual stress of weldments. First, flow properties can be evaluated by defining a representative stress and strain from analysis of deformation behavior beneath the rigid spherical indenter and the parameters obtained from instrumented indentation tests. For estimating residual stress, the deviatoric-stress part of the residual stress affects the indentation load-depth curve, so that by analyzing the difference between the residual-stress-induced indentation curve and residual-stress-free curve, the quantitative residual stress of the target region can be evaluated. The algorithm for flow property evaluation was verified by comparison with uniaxial tensile test and the residual stress evaluation model was compared to mechanical cutting and ED-XRD results.

• Proceedings of the KSR Conference
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• 2010.06a
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• pp.72-79
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• 2010

The significant of continuous welded rail (CWR) management is growing because KORAIL has the plan to convert the whole of conventional railway lines into CWRs through continuous activities since constructed the CWR track with 1.8km in Gyeongbu line in 1966. The CWR recently is needed a efficient management method because it is difficult to manage the CWR by the poor of technic and equipment, limited maintain labor force and shorted the maintain work time of CWR caused by industrialization, greenhouse effect and global warming In this point, The 70ton Tenser's which is using in the rail site has been analysised with no extra tenser's capacity in case of the under low temperature and exceed the length of 1km as a result of reviewing the CWR-related rules and standards, a series of records of safety accidents, operation obstacles, and the situation of broken rails published by KORAIL, existing rail temperature measurements, and CWR researches. Therefore avoid the excessive plan of the first set-up section, choice the proper time in the normal temperature that is possible to weld the rail, turning the difference of rail temperature and Installation temperature down is desirable.

• Communications for Statistical Applications and Methods
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• v.18 no.5
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• pp.581-594
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• 2011

The traditional method of 3+3 standard design and model-based Bayesian continual reassessment method (CRM) are commonly used in Phase I clinical trials to identify the maximal tolerated dose(MTD) of a new drug. In this paper we review clinical examples of Phase I trials that were carried out in patients with refractory or relapsed leukemia and myelodysplastic syndrome. The recently proposed 3+1+1 design and rolling-6 design can shorten the trial duration, when a very slow accrual of patients with a simple 3+3 standard design may result in the untimely termination of trials. Too conservative approaches in determining the dose levels in Phase I clinical trials can leave clinical investigators unable to accurately determine the MTD. When determining future patient doses, the designs that use a time-to-event CRM can cooperate late toxicities by accounting for the proportion of the observation period of each enrolled patient. With the CRM design, simulations under different scenarios during the trial are important in detecting the under- or over-estimation of the initial estimate of the dose-limiting toxicity rate for each dose level. We present the advantages and drawbacks of the designs used in Phase I clinical trials for leukemia patients.

• Korean journal of communication and information
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• v.60
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• pp.5-27
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• 2012

The purpose of this study is to explore the journalist Song Kun-Ho's ideas of Korean Journalism. The journalist Song Kun-Ho was born in 1926 and passed away in 2001. He became a reporter in 1953 when he was a student at department of law of Seoul National University. He has worked for several media and resigned the executive editor at the Dong Ah Ilbo in 1975. At that time, while many reporters of the Dong Ah Ilbo struggled for the freedom of the press, he tried to protect reporters and independence of media. After his resignation of the executive editor, he wrote many columns and several books for Korean nationalism and the democracy of journalism. Instead of working for the authoritarian military regime, he chose a lonely and rough life as an intellectual journalist in action. Finally, he, as a president, established the Hankyoreh daily newspaper which was funded by tens of thousands citizens. He passed away in 2001. His ideas of Korean journalism are nationalism, democracy, and independency. These ideas are very important to restore democratic journalism which has been at risk during the Lee Myung-bak administration.

• Journal of the Korean GEO-environmental Society
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• v.21 no.9
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• pp.25-32
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• 2020

The underground utilities installed under the ground is an important civil engineering structure, such as water supply and sewerage pipes, underground power lines, various communication lines, and city gas pipes. Such underground utilities can be exposed to risk due to external factors such as concentrated rainfall and vehicle load, and it is important to select and construct an appropriate backfill material. Currently, a method mainly used is to fill the soil around the underground utilities and compact it. But it is difficult to compact the lower part of the buried pipe and the compaction efficiency decreases, reducing the stability of the underground utilities and causing various damages. In addition, there are disadvantages such as a decrease in ground strength due to disturbance of the ground, a complicated construction process, and construction costs increase because the construction period becomes longer, and civil complaints due to traffic restrictions. One way to solve this problem is to use a liquid filler. The liquid filler has advantages such as self-leveling ability, self-compaction, fluidity, artificial strength control, and low strength that can be re-excavated for maintenance. In this study, uniaxial compression strength test and fluidity test were performed to characterize the mixed soil using marine clay, stabilizer, and in-situ soil as backfill material. A freezing-thawing test was performed to understand the strength characteristics of the liquid filler by freezing, and in order to examine the effect of the filling materials on the corrosion of the underground pipe, an electrical resistivity test and a pH test were performed.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.33 no.3
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• pp.1203-1213
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• 2013

Governmental accounting system has changed from budgetary accounting on the basis of cash and bookkeeping by single entry to financial accounting on the basis of accrual and bookkeeping by double entry. In the context of this transition, infrastructure becomes considered an asset in accounting, and resulting accounting methods also take different approaches from conventional budgetary accounting. Financial accounting system defines expenditures into two categories, i.e. capital expenditure(CAPEX) and operational expenditure(OPEX), and stipulates that the expenditure shall be divided into those two categories before accounting. The construction and expansion of infrastructure must be considered a CAPEX because it means a sort of asset acquisition, but with regard to applications in practical accounting, it is actually challenging to judge whether any expenditure associated with maintenance works (including repair and service) during use of infrastructure acquired shall be considered CAPEX or OPEX. This paper suggested an asset management based accounting method for sewer maintenance expenditure. And it applied the method to actual accounting cases and analyzed them in comparison with conventional financial information. As a case study result, Sewer asset value of S city increased approximately 700 hundred won because sewer maintenance expenditure are classified between OPEX and CAPEX according to the proposed accounting method. It is expected that the proposed accounting method will contribute significantly to providing any proper sewer asset value information.

• The Journal of the Korea Contents Association
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• v.11 no.8
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• pp.211-220
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• 2011

The study conducted a survey on the perception level for radiological technologists with 321 nurses and auxiliary nurses working at university hospitals in Busan in order to supply preliminary data to enhance the status as well as professional images of radiological technologists. The result shows the perception level of $3.02{\pm}0.42$ with the highest score for the professional image and the lowest score for the business image. By question, 'they are professional' gets the highest score while 'they understand problems of patients well' gets the lowest. Among respondents, those who are well aware of education courses as well as leading organization of examination and who answer as a health care provider or a medical technician under the medical law show a high level of perception while those who answer as technician show a low perception level. Those who agree with radiologists as a career and consider their status as high in medical institutions have a high level of perception. In order to improve the perception level, individuals as well as associations' promotion and strategies are required to fix the title and enhance the negative images through active interests and kind attitudes toward patients. Also, efforts to escape from previous images limited to technical colleges, to vitalize academic conference and remedial education, and to frame the law of professional radiological technologists system are asked to heighten the qualification and status of radiological technologists. More than that, advertising and monitoring via mass media are needed to develop the image as professional career men as well.

• The Journal of the Korea Contents Association
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• v.20 no.2
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• pp.36-50
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• 2020

YouTube as a news channel is gaining popularity because it offers more interesting and in-depth news than traditional news media. However, YouTube has been criticized for its distribution of false information (or fake news) in Korea. Politicians are actively proposing a variety of bills to regulate YouTube's false information and a lot of studies proposed how to regulate YouTube's false information. This study looked at the users' experience and perception of false information and identified factors that affected the regulation of YouTube news. The results showed that the conservatives and the moderate groups were exposed to false information more than the progressives, and those in their 60s believed that false information was distributed on YouTube rather those in their 20s to 50s. The more people value freedom of expression, the more people trust TV Chosun news, the more people tend to oppose the regulation of information on YouTube. On the other hand, it turns out that the more people trust the news on both terrestrial broadcasting networks and JTBC, and the more people value the enlightening aspects on the news, the more they approve of Youtube regulation.

• The Journal of the Korea Contents Association
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• v.13 no.2
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• pp.322-330
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• 2013

The purpose of this study was to examine the influence of critical thinking, clinical decision making and job satisfaction of 132 dental hygienists. The data was collected from 1st May to 31th October, 2012 in Ulsan, Pusan and Gyeongsangnam-do areas. The majority participants were female, 30.6 years old, graduate diploma course of dental hygienist, and working in dental clinics. In critical thinking, truth-seeking was highest score, 3.36 but maturity was lowest score, 3.00. In clinical decision making, canvassing of objectives & values was highest score 3.39, but search for alternatives or options was lowest score, 3.10. In job satisfaction, professional status was highest score 3.20, but incomes & promotion was lowest score 2.84. In correlation between general characteristics and critical thinking, there was significantly different in religion, education status, total working period and working areas. There was significantly different with religion and education status in clinical decision making, And There was significantly different with religion and education status, total working period, and working areas in job satisfaction. Critical thinking, clinical decision making and job satisfaction was positive relationship. To improve professional competence and job satisfaction of dental hygienist it need to use actively the critical thinking and clinical decision making. And it need to prepare the education and strategy to increase the job satisfaction of dental hygienist.