• Journal of the Korean Ceramic Society
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• v.41 no.10 s.269
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• pp.728-734
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• 2004

The effect of microstructure of WC-Co substrates which have different WC grain sizes from submicron to 5 $\mu$m on the diamond-substrate adhesion strength was investigated. The substrates were pre-treated by two methods : chemical etching with Murakami's solution and subsequently with $H_2SO_4$, and thermal heat-treatment. The adhesion strength was estimated by degree of peeling after Rockwell indentation. Diamond films of 20 $\mu$m thickness deposited on the heat-treated substrates showed an excellent adhesion strength at the load of 100 kg, which ascribed to the large and elongated WC grains. However, the cutting edge of insert was deformed after heat treatment and the surface morphology of heat treated substrate strongly affected on the surface roughness of the deposited diamond films. On the contrary, the diamond film of 10 $\mu$m in thickness on the chemically etched substrates of average WC grain size over 2 $\mu$m showed good adhesion strength enough not to peel-off under a load of 60 kg. Especially, the substrate of average WC grain size over 5 $\mu$m exhibited much improved reliability of adhesion comparing with the substrate of average grain size under 2 $\mu$m. No substrate deformation was observed in this case after the chemical etching, which is more advantageous and more practical in terms of precious machining than the heat treatment case.

• Journal of Korean society of Dental Hygiene
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• v.8 no.1
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• pp.93-105
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• 2008

In order to provide basic information to help dental medical service with supplying gratifying service for patients. the survey is conducted on the patients who frequently visited dental clinics located in the areas such as Seoul, Kyoungi, and Incheon from May of 2006 to June. The survey results are as following : 1. Judged from the factors to make patients choose one dental clinic over another. the low cost of treatment accounts for 32.8%. and followed by physician's academic background / career experiences with 20.5%. In case of recommending to their acquaintances, physician's proficiency in treatment is ranked high as 56.7%. 2. For most desirable facilities for dental hospitals. the results indicate that cutting-edge medical equipment holds 46.7% and followed by a comfortable waiting room with 32.8%. 3. Examined the questions of what patients are most satisfied with dental clinics. 43.1% of respondents point out kind and detailed explanation. 14.1% also responds to constant care after the treatment. This result suggests that after-care and detailed explanation also play an important role in dental care as well as the treatment itself. 4. For desirable services in the waiting room. 28.5% of the respondents choose a selection of magazines and newspaper and 18.7% say that they want to converse with the staff. As to how long can wait with patience. 38.2% of the participants agree on as long as 20 minutes. 5. Among unsatisfactory sources against dental clinics while visiting, the high cost of the treatment is scored high as 34.1% and followed by a long waiting time with 22.1%. The figure points to the fact that dental medical clinics should consider these two factors to solve in the future. In case where patients find the treatment discontent and they are asked what to do, 36.4% of the respondents respond that they go to a different hospital without saying anything. As to the enquiry about how the complains should be dealt, 46.% wishes that the matter should be taken care immediately upon complaining, 21.8% suggests that they like to feel understood and acceptable when presenting complaints.

• Archives of design research
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• v.19 no.5 s.67
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• pp.383-394
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• 2006

In 2005, Giorgetto Giugiaro unveiled the Ferrari GG50 at the 50th anniversary celebration of his design career. Beginning his career at the age of 17, he is a master designer who has achieved design revolution by uniting creativity, design methodology, and technology. He has been awarded a number of international prizes for his exquisite achievements and reputation for car design. Carrozzeria of ITAL DESIGN, founded by Giugiaro, is a company whose ideas combine cutting-edge technology and high quality craftsmanship. Beginning in car design, ITAL DESIGN achieved a positive reputation internationally and, since 1999, has expanded even more rapidly under its new name, ITAL DESIGN-GIUGIARO. The owner of 12 affiliates worldwide, all service systems are buyer-oriented, ensuring the highest level of technical consulting. Beginning with the 1971 Alfa Romeo Alfasud, the 1st major project, more than 100 cars have been designed in the past 35 years, leading to the production or in million cars by major motor companies around the world. Giugiaro has focused on practical performance as well as external beauty in his car design, the best of which enter the mass market. With his philosophy of "I want to be the 1st customer of my design" Giugiaro design invites customer participation and input to meet their needs and demands. Free from the routine, typical image, Giugiaro design has raised the bar for creativity and thinking beyond traditional values and ideologies.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.19 no.5
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• pp.117-121
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• 2018

As the paradigm shifts in the era of accelerated technological development and technology convergence, the defense sector is pursuing national defense research and development through selection and concentration, as well as the expansion of investments to develop defense science and technology to the highest possible level. In addition to investing heavily in cutting-edge weapons and core technologies that are consistent with the future, the defense sector is also developing investment strategies within a limited budget. In the private sector, the PD system has been introduced in order to maximize the performance of R&D policy and to improve the professionalism and responsibility of planning & management. In accordance with this trend, in the field of defense, the PD system of defense technology with specialization is being promoted, in order to strengthen the task planning capacity and to promote the utilization of private technology. Considering the need for coherent technical support for the core technology developed by R&D, the improvement of open technology planning systems and expansion of inter-civil & technical linkage, the use of the PD system in the defense field is indispensable. In this study, we review similar cases abroad and at home to examine the introduction and management of the PD system for defense technology. This study is based on the current state of the defense technology PD system that is being pursued.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.16 no.3
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• pp.1645-1651
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• 2015

This paper describes the changes of shape accuracy in workpiece materials depending on the turning clearance angle. The experiments started from choosing three workpiece materials, SM45C(machine structural carbon steel), STS303(stainless steel) and SCM415 (chrome-molybdenum steel). The experiments showed specifically how features of selected materials changed when they were processed with diverse machining depths, 0.1 mm, 0.2 mm and 0.3 mm, with various negative angles, $0.0^{\circ}(-6.0^{\circ})$, $0.3^{\circ}(-6.3^{\circ})$ and $0.9^{\circ}(-6.9^{\circ})$, and called cutting edge inclination starting from a fixed rotational speed, 2,500 rpm, focusing on the feed rate, 0.07 mm/rev and 0.10 mm/rev. The results of the accuracy of processing, cylindricity, deviation from coaxiality, etc. were compared using the graph and table. The accuracy of cylindricity in the order of degree $0.0^{\circ}{\rightarrow}0.3^{\circ}{\rightarrow}0.9^{\circ}$ depending on the workpiece materials showed the best cylindricity when it was $0.9^{\circ}$. In conclusion, the accuracy improved in specific degrees irrespective of the quality of the materials when the bite negative angles increased. This means that workability improved in these experiments. In addition, the processing shape changed depending on depth of the cut and feed rate.

• Journal of Technology Innovation
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• v.25 no.4
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• pp.285-311
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• 2017

PSL-II Accelerator is a large-scale research facility located in Pohang, which was established in 1988 and operated since 1995. It is a program to be promoted to contribute to basic science research in Korea by applying it to cutting-edge research in the field of basic and applied science. It is estimated that around KRW 787.9 billion was invested for construction and operation in the near-30-year period until 2016. Although there have been various evaluations of the need, importance and effectiveness of accelerator in relation to the accelerator policy, most of them emphasize the successful outcome of the present time and suggest the government's need for sustained support in the future or suggest policy implications for improving the policy in a comprehensive manner. And there was no systematic analysis of the results on a comprehensive review or the various policy evaluations of the accelerator policy. In this study, three stages of PSL-II accelerator program were evaluated, and five main criteria of policy activity were considered. The purpose of this study is to suggest the policy implications related to the principles of policy activity which is essential in construction and operation of similar large-scale research facilities in addition to PSL-II accelerator.

• Journal of Digital Contents Society
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• v.3 no.2
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• pp.211-220
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• 2002

It has not been long since the current form of PDA began to be used widely. The PDA, which first came out in a recognizable form in the market a decade ago, multiplying the number of users, has recently been developed in various forms. It began to make cutting-edge technology available in PDA, and to be subdivided into various forms appropriate for special purposes, which reflected the recent intense competition in the market. It included the function of mobile phone, in tandem with the original function of PDA, by which it brought about other synergy effects and corresponded with the purpose more solidly. Due to these recent changes, PDA has had a dramatically increasing number of users, as well as the wider scope of usage and practical application by introducing new technology. However, research is required in the fields of basic usage and interface. It is important to recognize that PDA is an apparatus that stores for the users contents and information suitable for them, and that responds to them in case of need. PDA therefore needs to convey what the users require more easily and speedily without errors, and to provide them with appropriate information and contents. This paper examined the extent to which the interface of PDA including the input of contents required by the user would be efficient by questionnaires. In addition, alternatives concerning a general application environment of PDA were suggested based on the result of this survey.

• The korean journal of orthodontics
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• v.41 no.4
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• pp.268-279
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• 2011

Objective: The purpose of this study was to compare self-drilling orthodontic mini-implants of different surfaces, namely, machined (untreated), etched (acid-etched), RBM (treated with resorbable blasting media) and hybrid (RBM + machined), with respect to the following criteria: physical appearance of the surface, measurement of surface roughness, and insertion pattern. Methods: Self-drilling orthodontic mini-implants (Osstem implant, Seoul, Korea) with the abovementioned surfaces were obtained. Surface roughness was measured by using a scanning electron microscope and surface-roughness-testing machine, and torque patterns and vertical loadings were measured during continuous insertion of mini-implants into artificial bone (polyurethane foam) by using a torque tester of the driving-motor type (speed, 12 rpm). Results: The mini-implants with the RBM, hybrid, and acid-etched surfaces had slightly increased maximum insertion torque at the final stage ($p$ < 0.05). Implants with the RBM surface had the highest vertical load for insertion ($p$ < 0.05). Testing for surface roughness revealed that the implants with the RBM and hybrid surfaces had higher Ra values than the others ($p$ < 0.05). Scanning electron microscopy showed that the implants with the RBM surface had the roughest surface. Conclusions: Surface-treated, self-drilling orthodontic mini-implants may be clinically acceptable, if controlled appropriately.

• Strategy21
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• s.43
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• pp.5-28
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• 2018

The tensions between the U.S and China, which form the two pillars of the G2 era, seem to have persisted even after the Trump administration inaugurated. The strong confrontation between the two in recent foreign security issues may drive to develop an inadvertent military conflict, and it is high likely to occur in the maritime are. The purpose of this study is not only to analyze the balance of modernized naval forces in the PLAN through naval strategy changes and weapons system modernization trend, but also to predict the impact of the geographical proximity difference on the balance of naval forces in the disputed areas. It examined the impact of distance and geography on naval power by assessing the modernization pattern of the PLAN and capabilities in the context of two scenarios at different distances from China by 2020: one centered on Taiwan and the other on the Spratly Islands. The PLAN's strategy had impact on operational concept and forces construction. First, from the viewpoint of operation operational concept, it can be seen that the passive defense is changing into active defense. Second, in terms of power construction, it can threaten the surface and submarines of U.S power from a distance. And they generated follow three features; The ocean is not the focus of Chinese submarines, Horizontal and vertical expansion of Chinese naval vessels, The improvement of the suppression ability as the Chinese naval modernization ratio increases. The strength of the PLAN is dominant over the U.S in terms of reserves, and it can complement the qualitative deterioration by utilizing nearby bases in the vicinity of the mainland, such as the Taiwan Strait. However, due to the shortage of aircraft carriers, there is a possibility that it will take some time to secure the advantage of air and ocean in the amphibious operation. Therefore, as the dispute is prolonged, China may fail to achieve its original goal. In addition, the lack of cutting edge Commanding Ships may bring to weaken the C2 capabilities. At results, it is expected that PLAN will not be able to have a superiority in the short term due to lagging behind U.S advanced technology. Nevertheless, PLAN has strengthened its naval power through modernization sufficiently and it is highly likely to use force. Especially, it is more likely in the region where the naval power operation like the Taiwan Strait is possible with the almost equality to that of the United States. China will continue to use its naval forces to achieve a rapid and decisive victory over U.S in the close area from the land.

• Korea Journal of Hospital Management
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• v.23 no.1
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• pp.78-86
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• 2018

Purposes: This study identifies local Chinese consumers' standard for selecting medical care provider and their standard for choosing medical staff, as well as their expectations and concerns regarding Korean medical care providers. Methodology: A survey was conducted in China, to identify Chinese medical care consumers' standards for selecting a medical provider and the factors that influence their use of general hospitals. A total of 1,500 people across three cities, between the ages 18 and 60 participated in the survey. Moreover, a multiple logistic regression analysis was used to analyze the factors that affect Chinese medical care consumers' use of general hospitals. Findings: A total of 75.5 percent respondents chose general hospitals as their most frequently-used medical provider. Those who have health insurance, visit general hospitals as outpatients or are hospitalized more frequently than those who do not have a health insurance. Furthermore, those who have private insurance visit general hospitals as outpatients or are hospitalized more frequently than those who are not signed up for private insurance. Major standards for selecting a hospital included: the doctor's skills, word-of-mouth regarding the hospital, and distance to the hospital from the respondents' home. Standards for choosing medical personnel included word-of-mouth regarding the medical team, recommendations from family members or acquaintances, and medical team's notoriety. Friends and neighbors, family members, television and other media outlets were the channels for acquiring information on a hospital. It was found that Chinese people mostly visit the cardiovascular department of Korean hospitals for treatment. For using Korean hospitals in China, the majority of respondents answered that they were concerned about the cost. Practical Implications: Backed by highly skilled medical experts and cutting-edge technology, Korean medical care providers are attempting to enter China's medical care market. To succeed in China's medical care market, it is vital to conduct a clear and precise analysis.