• Journal of the Korean Chemical Society
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• v.40 no.8
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• pp.535-541
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• 1996

In preparation of fine alumina powders with use of vesicle, the effect of variation of pH in extravesicular dispersion system to mechanism of precipitation and shape and size distribution of precipitate was investigated. The results of observation by TEM and turbidimeter were obtained as follows. Reaction between aluminum ion and hydroxyl ion to produce precipitate within vesicle was initiated at pH 11.4 and spherical fine precipitates, about 50 nm size, were formed at pH 12.0. About pH 12.3, size of precipitates in vesicle grew twice as great as those formed below pH 12.0 because of the agglomeration and coalescence of vesicleswith time.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.17 no.5 s.122
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• pp.405-414
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• 2007

In recent years, experimental and theoretical studies show that turbulent flows looking disordered have a definite structure produced repetitively with visible order. As a core structure of turbulence, hairpin vertices are believed to play a major role in developing and sustaining the turbulence process in the near wall region of turbulent boundary layers and may be regarded as the simplest conceptual model that can account for the essential features of the wall pressure fluctuations. In this work, fully developed typical hairpin vortices are focused and the associated surface pressure distributions and their corresponding spectra are estimated. On the basis of the attached eddy model, the overall surface pressure spectra are represented in terms of the eddy size distribution. The model is validated by comparison of predicted wavenumber spectra with existing empirical models, the results of direct numerical simulation (DNS) and also spatial correlations with experimental measurements.

• KIISE Transactions on Computing Practices
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• v.23 no.9
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• pp.535-541
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• 2017

Today, the scale of the computer software market has increased, and massive sized software has been developed to satisfy diverse requirements. In this context, software complexity is increasing and the quality of software is becoming more difficult to manage. In particular, software reuse is important for the improvement of the environments of legacy systems and new system development. In this paper, we propose a method to reuse modules that are certified by quality. Reusable levels are divided into code area (method, class, and component), project domain, and business levels. Based on the coupling and cohesion of software complexity, we propose a reusable module extraction mechanism with reusability metrics, which constructs a visualization of the "reusable module's chunk" based on the method and class levels. By applying reverse engineering to legacy projects, it is possible to identify reusable modules/objects/chunks. If these modules/objects/chunks are to be reused to develop an extension system or similar new system, we need to ensure software reliability in order to reduce the time and cost of software development.

• The Journal of the Korea Contents Association
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• v.15 no.9
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• pp.351-363
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• 2015

Discourse analysis is useful for examining discourse characteristics of dementia patients and differentiating them from normal adults. However, inconsistent tasks, transcription methods and measures have been utilized, thus analyses were inevitably unsystematic. The purpose of this study was to investigate tasks, transcription methods and measures of discourse studies in dementia. Studies on dementia discourses written in English were collected via Scopus database containing abstracts and citations from 2005 to 2014, and were analyzed in detail. From the results, the most frequently used task was 'storytelling-topic'. It was observed that use of consistent transcription conventions rendered more reliable transcription data. Measures could be categorized into coherence, cohesion, productivity, propositional syntactic lexical analysis, and fluency, and each category belonged to discourse processing levels (i.e., processing of conceptual networks, propositions, and natural language units). In conclusion, future research warrants not only utilization of discourse tasks depending on dementia types and features, but also application of consistent transcription conventions. Additionally, measures based on the discourse processing theory would enable us to systematically interpret discourse studies.

• Journal of the Korean Ceramic Society
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• v.36 no.2
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• pp.159-166
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• 1999

The physical properties and microstructural changes with heat-treatment of opacified silica aerogels doped by TiO2 were investigated. Monolithic SiO2-TiO2 aerogels were prepared by supercritical drying (25$0^{\circ}C$, 1250 psig) of wet gel obtained by adding titanium isopropoxide to prehydrolyzed TEOS-isopropanol solutions. The density and the porosity of SiO2-10 mol% TiO2 aerogels were 0.23 g/㎤ and 90%, respectively. During supercritical drying, the linear shrinkage of aerogels increased with increase in the titanium content an TiO2 was transformed to the anatase phase as well as particls agglomerates led to TiO2 clusters of 100~800 nm dispersed homogeneoulsy in the silica matrix. The IR transmittance of opacified silica aerogels was very low in the region of wavelengths below 8 ${\mu}{\textrm}{m}$ compared with pure silica aerogels and SiO2-TiO2 aerogels showed the high thermal stability of microstructures up to $600^{\circ}C$.

• Korean Journal of Food Science and Technology
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• v.30 no.6
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• pp.1301-1306
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• 1998

This study was conducted to investigate the effect of soybean protein isolate (SPI) on the properties of noodle which was made of composite flour blended with SPI extracted at acidic (pH 2.0, 3.0), neutral (pH 7.0) and alkaline (pH 10.0, 12.0) conditions. L-value of dry and cooked-moodle which were made of composite flour was lower than that of 100% wheat flour, but a and b-value wete higher than those of 100% wheat flour, Optimal cooking time of dry-noodle which was made of composite flour was longer than that of 100% wheat flour, but the weight, volume and water absorption of the cooked-noodle were lower than those of cooked-noodle of 100% wheat flour. Breaking force of dry-noodle which was made of composite flour blended with $SPI-2,\;SPI_3,\;SPI_{7}$, and $SPI-{10}$ was lower than that of 100% wheat flour, but the breaking force of dry-noodle which was made of composite flour blended with $SPI-{12}$ at level of 5% and 10% was same as that of 100% wheat flour. Springiness and cohesiveness of the cooked-noodle which was made of composite flour were same as those of 100% wheat flour, but chewiness and hardness were higher than those of 100% wheat flour.

• Journal of the Korean Geographical Society
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• v.40 no.4 s.109
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• pp.402-415
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• 2005

This study inquired the features of restructuring of shipbuilding industry and structure of community cooperation. The Sinhyeon-eup region has experienced rapid changes as a large shipyard location. Prior to Korea, Japan has developed the cooperation of company-community-residents relationships and the reorganization of location systems through division and accumulation system. The restructuring of shipbuilding industry in Korea have focused on the improvement of business environment. So they have not been efficiently settled in the accumulation and the cooperation structure between company and region. Japan established the organic cooperation structure of company and community before the large restructuring, while the shipbuilding industry city of our country commenced it with the crisis of community by the restructuring. In the Sinhyeon-eup region, The connecting ring among the production sections of a core company in center is established. However the structure of community cooperation is weak. The structure of community cooperation as local governance consist of company, pubic institution, local residents, and regional expert. This structure can be a rational channel in which it can not only strengthen the cohesion of the community, but also solve the present questions of the industrial city.

• 한국IT서비스학회:학술대회논문집
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• 2002.06a
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• pp.96-107
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• 2002

21세기를 맞이하는 기업은 세계화와 국제화, 정보의 다양화 및 분산화, 제품수명주기의 단축과 수익률의 감소, 고품질의 제품, 지식산업의 등장, 고객 욕구의 증대 등 다양한 내 ${\cdot}$ 외적 환경변화에 대응해야 하고 경쟁우위를 확보하기 위해 끊임없이 기업의 변화능력을 확보해야 한다. 기업은 제품을 생산하여 판매하는 기업의 시스템 전체가 경쟁력을 갖추어 총체적 우위를 확보하고 고객의 기호와 감성에 호소하는 제품을 만들 수 있도록 다양한 정보를 제공하는 시스템을 필요로 하게 되었다. 즉, 시간과 서비스에 뒤진 고객지원체계는 기업의 성장에 절대적인 마이너스 요인이므로 고객 정보의 효율적 관리, 고객 요구에 대한 신속한 대응, 정기적 고객만족도 조사 등 고객이 원하는 것을 재빠르게 얻어낼 수 있는 고객 친밀형 정보시스템의 확립이 요구되는 것이다. 이를 해결해 줄 수 있는 새로운 경영정보시스템이 바로 WebERP인 것이다. WebERP는 기업의 원활한 자재, 구매활동을 위해 제안된 MRP에서 시작되었으며, 생산관리의 개념을 포함하고 있는 MRPII로 확대되었다가 다시 인사나 회계, 재무 등 조직이나 기업의 전업무영역을 수용하는 종합경영정보시스템으로 발전된 것이다. 현재는 전자상거래와 관련하여 WebERP의 필요성이 부각되었고, 모기업과 협력사간의 구매발주 및 납품관리를 확대시켜 소모성자재(MRO: Maintenance, Repair & Operation) 및 기타 공동구매서비스와 유사업종간의 그룹을 형성하여 ASP(Application Service Provider)의 공동 환경을 이용한 WebERP 환경을 이용한 WebERP활용이 현시점으로 적실히 필요한 것이다. 이는 중소기업들의 공동 협업체제를 도모하여 외세를 대비하는 응집력을 확고히 함으로써 집단체제의 e마켓플레이스 확립과 더불어 국제경쟁을 대비한 방안으로서 집단 공동의 웹환경 인프라가 필요한 것이다. 이러한 배경에서 ASP환경을 이용한 WebERP활용방안과 시스템 구축전략을 경남지역의 기계산업정보화사업단이 추진하는 일반기계, 전기기계, 금속기계, 수송기계, 정밀기계의 5개 업종을 4,877개 기업 대상으로 추진하고 있으며, 그 중 WebERP의 모델로서 2003년도까지 50개 기업을 선정하고, 이는 5개 업종 골고루 선정하여 적용과 표준화 모델로 전개해 나가는 것을 정리한 것이다.

• Applied Chemistry for Engineering
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• v.23 no.3
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• pp.308-312
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• 2012

Nitrogen doped $TiO_2$ photocatalysts were prepared by ammonia for exploring the visible light photocatalytic activity. To explore the visible light photocatalytic activity of the nitrogen doped $TiO_2$ photocatalyst, the removal of methylene blue dye was investigated under the sunlight. SEM images showed that the flocculated particle sizes of N-doped $TiO_2$ decreased due to the reaction with ammonia. XRD patterns demonstrated that the samples calcined at temperatures up to $600^{\circ}C$ and doped with nitrogen using ammonia clearly showed rutile as well as anatase peaks. The XPS results showed that the nitrogen composition onto $TiO_2$ increased according to the reaction time with ammonia. Photocatalytic activity of the nitrogen doped $TiO_2$ was better than that of undoped $TiO_2$. Nitrogen doping onto the $TiO_2$ also affected the crystal type of $TiO_2$ photocatalyst.

• Journal of the Korean Society of Propulsion Engineers
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• v.11 no.2
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• pp.26-36
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• 2007

The thermal response characteristics of nozzle liner for a solid rocket motor applying highly aluminized PCP or HTPB propellant with slotted tube grain have been investigated. The SEM photographs of aluminum oxide particles taken from nozzle liner show that the PCP propellant with the finer and less contents of oxidizer can offer greater possibility for increasing aluminum agglomeration than the HTPB propellant. The PCP propellant shows locally greater mechanical erosion at 4 circumferential areas of the nozzle entrance in line with grain slot due to the impingement of large particles, but the HTPB propellant shows greater thermochemical ablation at the nozzle blast tube, the throat insert and the exit cone because of relatively much more mole fraction of $H_2O\;and\;CO_2$ in combustion gases.