• Proceedings of the Korean Society of Laser Processing Conference
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• 1998.11a
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• pp.0-0
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• 1998

-Part I- As market needs become more various, the production of smaller quantities of a wider variety of products becomes increasingly important. In addition, in order to meet demands for more efficient production, long-term unmanned factory operation is prevailing at a remarkable pace. Within this context, laser machines are gaining increasing popularity for use in applications such as cutting and welding metallic and ceramic materials. FANUC supplies four models of $CO_2$ laser oscillators with laser power ranging from 1.5㎾ to 6㎾ on an OEM basis to machine tool builders. However, FANUC has been requested to produce laser oscillators that allow more compact and lower-cost laser machines to be built. To meet such demands, FANUC has developed six models of Slab type YAG laser oscillators with output power ranging from 150W to 2㎾. These oscillators are designed mainly fur cutting and welding sheet metals. The oscillator has an exceptionally superior laser beam quality compared to conventional YAG laser oscillators, thus providing significantly improved machining capability. In addition, the laser beam of the oscillator can be efficiently transmitted through quartz optical fibers, enabling laser machines to be simplified and made more compact. This paper introduces the features of FANUC’s developed Slab type YAG laser oscillators and their applications. - Part II - All-solid-state lasers employing laser diodes (LD) as a source of pumping solid-state laser feature high efficiency, compactness, and high reliability. Thus, they are expected to provide a new generation of processing tools in various fields, especially in automobile and aircraft industries where great hopes are being placed on laser welding technology for steel plates and aluminum materials for which a significant growth in demand is expected. Also, in power plants, it is hoped that reliability and safety will be improved by using the laser welding technology. As in the above, the advent of high-power all-solid-state lasers may not only bring a great technological innovation to existing industry, but also create new industry. This is the background for this project, which has set its sights on the development of high-power, all-solid-state lasers with an average output of over 10㎾, an oscillation efficiency of over 20%, and a laser head volume of below 0.05㎥. FANUC Ltd. is responsible for the research and development of slab type lasers, and TOSHIBA Corp. far rod type lasers. By pumping slab type Nd: YAG crystal and by using quasi-continuous wave (QCW) type LD stacks, FANUC has already obtained an average output power of 1.7㎾, an optical conversion efficiency of 42%, and an electro-optical conversion efficiency of 16%. These conversion efficiencies are the best results the world has ever seen in the field of high-power all-solid-state lasers. TOSHIBA Corp. has also obtained an output power of 1.2㎾, an optical conversion efficiency of 30％, and an electro-optical conversion efficiency of 12%, by pumping the rod type Nd: YAG crystal by continuous wave (CW) type LD stacks. The laser power achieved by TOSHIBA Corp. is also a new world record in the field of rod type all-solid-state lasers. This report provides details of the above results and some information on future development plans.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.18 no.6
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• pp.703-709
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• 2017

Korea Utility Helicopter(KUH) is a project to replace the aging helicopter presently being operated by the military with a domestic helicopter. The auxiliary power unit is a device that supplies emergency power to the system by an alternator installed when the main generator fails and the start motor converts the electrical energy of the battery into mechanical rotational energy to rotate the auxiliary power unit engine. With continuing power and operation, defects of the starting motor were found and improvements were carried out to solve it. In the failure mode analysis, the causes of possible defects were classified into 5 categories. Analysis of the 5 factors revealed that the main cause of defects is mechanical wear, which was found to be related to spring pressure. 250 tests were conducted through the theoretically determined pressure and regression analysis was performed with 4 sampling.The results showed that pressure was related to wear rate. In conclusion, early wear and breakage due to wear can be controlled through spring force and test showed the prediction of wear and the validity of the result were confirmed.

• Journal of Advanced Navigation Technology
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• v.22 no.4
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• pp.264-270
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• 2018

In recent years, It is required to verify software reliability according to DO-178, which announced by radio technical commission for aeronautics (RTCA) and recognized by the Federal Aviation Administration (FAA), for civil aircraft developed or intended to fly in the United States or Europe. This is because the reliance on software in each field is deepening, and the efforts for improvement of software reliability have been made first in civil aviation field where economic and social impacts are catastrophic in the event of an accident. In this paper, we have identified some issues to be considered for requirements-based reliability verification required by DO-178 to improve software reliability and present the major elements of the present weapon system acquisition procedure of DAPA for each stage. In addition, we analyzed the results of applying the identified main check factors to a domestic aircraft development project based on the information accumulated in overseas aircraft development projects. As a result, we have shown that it is possible to verify requirements-based software reliability according to DO-178 by adding key checkpoints to the current weapon system acquisition procedure and providing objective inspection criteria.

• Restorative Dentistry and Endodontics
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• v.30 no.6
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• pp.442-449
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• 2005

The purpose of the present study was to evaluate the relationship between the amount of cuspal deflection and linear polymerization shrinkage in resin composite and polyacid modified resin composite, For cuspal defelction and shrinkage measurement, Dyract AP, Compoglass F, Z100, Surefil. Pyramid, Synergy Compact, Heliomolar and Heliomolar HB were used. For measuring polymerization shrinkage, a custom made linometer (R&B, Daejon, Korea) was used The amount of shrinkage among materials was compared using One-way ANOVA analysis and Tukey's test at the $95\%$ of confidence level For measuring cuspal deflection of teeth, standardized MOD cavities were prepared in extracted maxillary premolars. After a self-etching adhesive was applied, cavities were bulk filled with one of the felling materials. Fifteen teeth were used for each material. Cuspal deflection was measured by a custom made cuspal-deflection measuring device. One-way ANOVA analysis and Tukey's test were used to determine differences between the materials at the $95\%$ of confidence level, Correlation of polymerization shrinkage and cuspal deflection were analyzed by regression analysis. The amount of polymerization shrinkage from least to greatest was Heliomolar, Surefil < Heliomolar HB < Z100, Synergy Compact < Dyract AP < Pyramid, Compoglass F (p<0.05). The amount of cuspal deflection from least to greatest was Z100, Heliomolar, Heliomolar HB, Synergy Compact Surefil < Compoglass F < Pyramid, Dyract AP (p < 0.05). The amount of polymerization shrinkage and cuspal deflection showed a correlation (p<0.001).

• Journal of KIISE:Computing Practices and Letters
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• v.5 no.6
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• pp.727-737
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• 1999

프로세스 중심 소프트웨어 개발 환경(PSEE : Process-centered Software Engineering Environment)은 소프트웨어 개발자를 위한 여러가지 정보의 제공과 타스크의 수행, 소프트웨어 개발 도구의 수행 및 제어, 필수적인 규칙이나 업무의 수행등과 같은 다양한 행위를 제공하는 프로세스 모형의 수행을 통하여 소프트웨어 개발 행위를 지원한다. SEED(Software Engineering Environment for Development)는 효율적인 소프트웨어 개발과 프로세스 모형의 수행을 제어하기 위해 ETRI에서 개발된 PSEE이다.본 논문에서는 SEED에서 프로세스 모형을 설계하기 위해 사용되는 SimFlex 프로세스 프로그래밍 언어와, 수행지원시스템인 SEED Engine의 구현에 대하여 기술한다. SimFlex는 간단한 언어 구조를 가진 프로세스 프로그래밍 언어이며, 적절한 적합화를 통하여 다른 PSEE에서 사용될 수 있다. SimFlex 컴파일러는 SimFlex에 의해 기술된 프로세스 모형을 분석하고, 모형의 오류를 검사하며, SEED Engine에 의해 참조되는 중간 프로세스 모형을 생성한다. 중간 프로세스 모형을 사용하여 SEED Engine은 외부 모니터링 도구와 연관하여 사용자를 위한 유용한 정보뿐만 아니라 SimFlex에 의해 기술된 프로세스 모형의 자동적인 수행을 제공한다. SimFlex 언어와 수행지원 시스템의 지원을 통하여 소프트웨어 프로세스를 모형화하는데 드는 비용과 시간을 줄일 수 있으며, 편리하게 프로젝트를 관리하여 양질의 소프트웨어 생산물을 도출할 수 있다. Abstract Process-centered Software Engineering Environments(PSEEs) support software development activities through the enaction of process models, providing a variety of activities such as supply of various information for software developers, automation of routine tasks, invocation and control of software development tools, and enforcement of mandatory rules and practices. The SEED(Software Engineering Environment for Development) system is a PSEE which was developed for effective software process development and controlling the enactment of process models by ETRI.In this paper, we describe the implementation of the SimFlex process programming language used to design process models in SEED, and its runtime support system called by SEED Engine. SimFlex is a software process programming language to describe process models with simple language constructs, and it could be embedded into other PSEEs through appropriate customization. The SimFlex compiler analyzes process models described by SimFlex, check errors in the models, and produce intermediate process models referenced by the SEED Engine. Using the intermediate process models, the SEED Engine provides automatic enactment of the process models described by SimFlex as well as useful information for agents linked to the external monitoring tool. With the help of the SimFlex language and its runtime support system, we can reduce cost and time in modeling software processes and perform convenient project management, producing well-qualified software products.

• Journal of KIISE:Software and Applications
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• v.29 no.7
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• pp.476-486
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• 2002

CBD(Component Based Development) has become the best strategical method for the business application. Because CBD is a new development paradigm which makes it possible to assemble the software components for application, it copes with the rapid challenge of business process and meets the increasing requirements for productivity. Since the business process is rapidly changing, CBD technology is the promising way to solve the productivity. Especially, the repository is the most important part for the development, distribution and reuse of components. In component repository, we can store and manage the related work-products produced at each step of component development as well as component itself. In this paper, we suggested a practical approach for repository construction to support and realize the CBD process and developed the CRMS(Component Repository Management System) as implementation product of the proposed techniques. CRMS can manage a variety of component products based on component architecture, and help software developers to search a candidate component for their project and to understand a variety of information for the component. In the paper, a practical approach for component repository was suggested, and a supporting environment was constructed to make CBD to be working efficiently. We expect this work wall be valuable research for component repository and the entire supporting Component Based Development Process.

• Anxiety and mood
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• v.4 no.1
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• pp.49-54
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• 2008

Objective : This article is a part of the Korean Medication Algorithm Project for Panic Disorder, which aims to build consensus regarding the diagnosis, treatment response and achievement of clinical remission for patients with panic disorder in Korea. Methods : The questionnaire used in this article had parts : 1) diagnosis, 2) treatment response, and 3) remission for patients with panic disorder. The questionnaire was completed by each of 54 Korean psychiatrists who had much experience in treating patients with panic disorder. We classified the experts' opinions into 3 categories (first-line, second-line, and third-line) using the ${\chi}^2$-test. Results : Five factors were considered in this research : panic attack, anticipatory anxiety, phobic avoidance, severity of illness, and psychosocial disability. Most reviewers agreed that the presence of a panic attack was the most important factor in the diagnosis of patients with panic disorder. Phobic avoidance was included in the first-line category, whereas the severity of illness and psychosocial disability were included in the second-line category. Most reviewers also agreed that the presence of a panic attack was the most important factor in determining the appropriate treatment response, and it was included in the first-line category along with several other items. To determine remission status, the patients' scores on tests pertaining to the severity of panic attack, anticipatory anxiety, phobic avoidance, severity of illness and psychosocial disability should be less than 3.0-3.3 on a 9-point Likert scale. Conclusion : We suggest useful information for making a diagnosisof panic disorder, determining the appropriate treatment response and identifying remission in panic disorder patients on the basis of the results of a nationwide survey of experts in Korea.

• Biomaterials Research
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• v.22 no.4
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• pp.328-336
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• 2018

Background: Biogenic fabrication of silver nanoparticles from naturally occurring biomaterials provides an alternative, eco-friendly and cost-effective means of obtaining nanoparticles. It is a favourite pursuit of all scientists and has gained popularity because it prevents the environment from pollution. Our main objective to take up this project is to fabricate silver nanoparticles from lichen, Usnea longissima and explore their properties. In the present study, we report a benign method of biosynthesis of silver nanoparticles from aqueous-ethanolic extract of Usnea longissima and their characterization by ultraviolet-visible (UV-vis), Fourier transform infrared (FTIR) spectroscopy, transmission electron microscopy (TEM) and scanning electron microscopy (SEM) analyses. Silver nanoparticles thus obtained were tested for antimicrobial activity against gram positive bacteria and gram negative bacteria. Results: Formation of silver nanoparticles was confirmed by the appearance of an absorption band at 400 nm in the UV-vis spectrum of the colloidal solution containing both the nanoparticles and U. longissima extract. Poly(ethylene glycol) coated silver nanoparticles showed additional absorption peaks at 424 and 450 nm. FTIR spectrum showed the involvement of amines, usnic acids, phenols, aldehydes and ketones in the reduction of silver ions to silver nanoparticles. Morphological studies showed three types of nanoparticles with an abundance of spherical shaped silver nanoparticles of 9.40-11.23 nm. Their average hydrodynamic diameter is 437.1 nm. Results of in vitro antibacterial activity of silver nanoparticles against Staphylococcus aureus, Streptococcus mutans, Streptococcus pyrogenes, Streptococcus viridans, Corynebacterium xerosis, Corynebacterium diphtheriae (gram positive bacteria) and Escherichia coli, Klebsiella pneuomoniae and Pseudomonas aeruginosa (gram negative bacteria) showed that it was effective against tested bacterial strains. However, S. mutans, C. diphtheriae and P. aeruginosa were resistant to silver nanoparticles. Conclusion: Lichens are rarely exploited for the fabrication of silver nanoparticles. In the present work the lichen acts as reducing as well as capping agent. They can therefore, be used to synthesize metal nanoparticles and their size may be controlled by monitoring the concentration of extract and metal ions. Since they are antibacterial they may be used for the treatment of bacterial infections in man and animal. They can also be used in purification of water, in soaps and medicine. Their sustained release may be achieved by coating them with a suitable polymer. Silver nanoparticles fabricated from edible U. longissima are free from toxic chemicals and therefore they can be safely used in medicine and medical devices. These silver nanoparticles were stable for weeks therefore they can be stored for longer duration of time without decomposition.

• Journal of Korean Philosophical Society
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• v.131
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• pp.131-163
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• 2014

This Paper aims to elaborate on the origin of thinking mind. And this is a cooperative project between philosophy and neuroscience and brain science. I have written this paper in admiration for the achievements of twentieth century neuroscience and brain science, and out of desire to assist the subject in future. Much of the history of modern philosophy, from Descartes and Kant forward, consists of failed models of brain. As Edward O. Wilson precisely said, the shortcoming is not the fault of the philosophers, who have doggedly pushed their methods to the limit, but a straightforward consequence of the biological evolution of the brain. Guiding that investigation down pathways that will illuminate brain research is a task of neuroscience and brain science. Investigating logical relations among concepts is a philosophical task. If we are to understand the neural structures and dynamics that make perception, thought, intentional behaviour possible, clarity about these concepts and categories and their relations is essential. Hence our joint venture of philosophy and science. Sure, it is human beings that perceives, not parts of its brain. And it is human beings that who think and reason, not their brain. But the brain and its activities make it possible for human beings-not for it-to perceive and think, to feel emotions, and to form and pursue projects. Thus We try to investigate and reveal the origin of thinking mind as follow: 1) The difference between chimpanzee and human beings 2) brain and mind 3) the origin of thinking 4) the wisdom of nature.

• Korean Journal of Social Welfare Studies
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• v.47 no.1
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• pp.123-149
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• 2016

Purpose of this study is to find the way to improve older people's life satisfaction from identifying factors, which were derived from exploring several variables (perceived health, mental health, health literacy, and mental health literacy), affecting perception on ageing positively and negatively. This study used data (400 people age 65 and over) from survey on ageism and age integration conducted by 'supporting project of enhancing humanities and social capacity' of National Research Foundation of Korea. The results are as followed; 1) older people negatively perceived psycho-social ageing; 2) older people had high level of depression; 3) showing slightly low level of health literacy and mental health literacy; 4) depression, perceived health and mental health literacy were significant factors influence on perceived psycho-social aging. With these results, the ways were suggested to improve positive psycho-social ageing and quality of life.