• 한국음향학회지
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• 제19권4호
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• pp.37-44
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• 2000

본 논문에서는 인터넷 폰, 디지털 이동통신 등과 같이 낮은 비트율이 요구되는 분야에 사용될 수 있는 MPEG-4 오디오의 HVXC(Harmonic Vector eXcitation Coding) 알고리즘을 부동 소수점 DSP인 TMS320C6701에 실시간 구현한 내용을 기술한다. 실시간 동작을 위한 하드웨어 구조를 채택하였으며, 소프트웨어 최적화의 경우 연산 시간이 많이 소요되는 함수 루틴에 대한 C 언어 및 어셈블리 언어 레벨의 최적화를 수행하였다. 또한, DSP의 내부 프로그램 메모리의 프로그램 캐쉬로의 활용, DSP의 내부 데이터 메모리의 영역의 중첩 활용 및 background DMA 방식을 이용한 최적화를 수행하였다. 최적화 결과 2kbps및 4kbps의 비트율에서 압축 및 복원을 실시간으로 수행할 수 있으며, 인코더의 경우 2kbps의 경우에는 최적화 전에 비해 약 96% 정도로 수행시간을 단축하였다. 또한, 비공식 주관품질 평가에 의하면 2kbps의 비트율에서 약 MOS 2.45를 얻었다.

• 한국CDE학회논문집
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• 제15권5호
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• pp.362-374
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• 2010

Product Lifecycle Management (PLM) is an integrated business approach to manage the creation and distribution of product information throughout the product development process. From the product perspective, PLM encompasses a holistic approach to product development and product information management. It supports the integrated product information in conjunction with the efficient product structures and BOM (Bill Of Material), user interfaces, proper functions, design processes and enterprise integration. Therefore, PLM should not only satisfy required functions as an enterprise software but also offer a systematic method for the efficient application from the initial stage of its development. Recently, many shipyards have been considering the PLM as a strategic solution to get the efficient management of product information such as 3-D models, BOM, drawings, documents, and the other product data. Though many studies on PLM are performed, most of them are performed in a function-based approach adequate for mass productive assembly industries. It could not help having limitations on applying the proper PLM system to the shipbuilding business since the requirements of shipbuilding PLM are too diverse and huge to design the architecture. This study presents the PLM framework which effectively reflects the diverse requirements of shipbuilding PLM. In order to get the macroscopic architecture of shipbuilding PLM, authors suggest the four-tier architecture model which considers the various requirements collected from shipyards. Entities of ship design data are modeled BOM in terms of product structure and hierarchical class diagram. Applicable functions of shipbuilding PLM are also investigated by analysis of issues of ship design. Finally, by reflecting the design process of shipbuilding, To-Be ship design procedure cooperated with the suggested PLM framework has been summarized.

• 대한기계학회논문집A
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• 제20권1호
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• pp.146-153
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• 1996

A SCARA type direct drive robot which can be used in the assembly operation was designed and manufactured. Graphite fiber epoxy composite material was used in the fabrication of the robot arm structure in order to improve the speed of the robot arm with a high damping effect. For model-based control and sensitivity analysis of system parameters, the dynamic model of robot arm and drive servo amplifier parameters such as equivalent gains of PWM driver and velocity gains of servo system were estimated from frequency response tests. The complete dynamic model for overall robot system was used in the simulation of the open-loop control. The simulation results agreed reasonably well to the experimental results. The feedforward control using the dynamic models improved the trajectory tracking performance, decreasing the tracking error by factor of three compared with PID control. This study found that the inverse dynamic model of the robot arm including the drive servo system showed better performances than the case of arm dynamic model only.

• 한국융합학회논문지
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• 제2권2호
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• pp.27-34
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• 2011

본 연구는 호빙 가공공정 없이 워엄 휠 기어 형상을 만들기 위한 워엄 휠의 개발을 위한 제품을 만드는 것이다. 호빙 가공 공정이 없기 때문에, 증가된 생산성과 등가의 품질을 가지는 플라스틱 워엄 휠이 결국 만들어지게 된다. 그 결과, 이 제품은 현대 모비스, 만도, TRW, KOYO/NSK/Showa(Japan), Delphai(Amercia)에 판매 될 것이다. 핵심 기술 및 전략은 다음과 같다. 워엄 휠의 성형을 위한 기술 보호는 최근 "헬리컬 기어(No. 10-2008-0105908) 성형"이 특허 공정으로 되어 있다. 나아가, "보스 삽입을 위한 위치 결정을 위한 성형 시스템"을 위한 특허 절차가 준비 중이다. 기어 기계가공 절차 없이 호빙 머신에 기어 성형 절차로서, 무엇보다 먼저, 기어를 만드는 코어 개발 기술이 주된 주제이다. 따라서, 코어 및 성형 기초가 초기 순서로 개발되지 않아서, 현재 개발되는 워엄 휠의 경우, 기어는 이차적으로 호빙 M/C로 기계가공 된다. 최종적으로는, 성형 기초 구조체를 위한 특허가 본 연구결과로 만들어질 예정이다.

• 한국가구학회지
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• 제27권3호
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• pp.237-245
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• 2016

Single households currently account for 26.5% of all households and their number is expected to continue to rise, reaching 34.5% by 2035. An analysis of the consumption trends and needs of single households shows that they are rising as a new consumer group with a focus on investment on the individual and favouring: small but high-tech products: efficient use of limited resources: safety and peace of mind: self-improvement and leisure. Products which meet such demands are having an impact on the growth of home-furnishing market. An analysis of companies in Korea's home-furnishing market, with examples like the lifestyle company IKEA, shows a variety of brands such as SPA brand, furniture specialist, distributor and character products. And yet most are OEM products which lack differentiated product lines and compete with similar display and distribution structure. We needs the Single household consumption tendency of home-furnishing market and differentiation strategy through product analysis. In order to increase the value of companies in the home-furnishing market, in addition to differentiated design, product competitiveness must aspire to higher customer satisfaction with easy assembly, innovation in logistics, innovative sales methods such as virtual-reality simulation for products and space, individually-tailored furniture for the needs of single household and products which combine smart technology. For home-grown home-furnishing brands to have competitiveness, they must leverage on the strengths of the industry, offering differentiated and competitive products in a wider range of areas with convergence functions as well as differentiation in consumer interface and application of advancing technology; in-depth product research is called for.

• 한국소음진동공학회:학술대회논문집
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• 한국소음진동공학회 2006년도 춘계학술대회논문집
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• pp.309-313
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• 2006

Many researchers have studied on the lightness of automobile. These researches are such as a body shell, sub frame, fuel tank, engine etc. The transmission Part is a magnitude one in the aspect of weight. A drive shaft (propeller shaft) transmits the engine power to rear differential gear assembly. It is used in the compact car that is a single drive shaft. But in the case of long body cars such as SUV (Sports Utility Vehicle), truck and large vehicle, two or three divided drive shaft are used to prevent the vibration damage from a drive shaft that has been taken high torsion and rotation. This multi-divided drive shaft structure is so heavy because it is assembled by yoke, center bearing and solid spline axis. When the rear axle move up and down, the spline shaft adjust the variation of a length between the transmission and rear axle gearbox. In this paper, it is studied in the experimental method that is a bending vibration characteristic of slip in tube shaped propeller shaft. This type propeller shaft is developed to combine the spline axis with drive shaft and can be light in weight of transmission part.

• 공업화학
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• 제18권5호
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• pp.407-414
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• 2007

Moldflow사의 CAE 해석 프로그램인 MPI (Moldflow Plastics Insight)를 이용하여 PP(polypropylene)에 talc 20%가 들어간 수지를 사용한 자동차 공기 청정기 상부 덮개의 최적 공정을 찾았다. 핀 게이트가 하나인 기존 시스템을 CASE-1, 두 개로 새로운 공정을 CASE-2로 디자인하여 두 공정에 대한 유동 발란스 등을 비교하였다. CASE-2는 충진 시간이 더 짧아 생산성과 공정성의 향상이, 유동성과 부피수축율이 하부 덮개와 유사하게 나타나 조립성과 조립 후의 변형 및 물성발현이 향상되었다. 또한 전단속도와 전단응력의 해석결과, CASE-1의 문제점은 잔류 응력에 의한 것보다는 상 하부 덮개의 크기 차이에 의한 것으로 판단되며, 결국 수지의 배향 문제는 게이트 구조를 최적화 함으로써 파손 문제를 해결할 수 있을 것이라 예상된다.

• EDISON SW 활용 경진대회 논문집
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• 제3회(2014년)
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• pp.237-249
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• 2014

Deposition of amyloid-${\beta}$ ($A{\beta}$) proteins is the conventional pathological hallmark of Alzheimer's disease (AD). The $A{\beta}$ protein formed from the amyloid precursor protein is predominated by the 40 residue protein ($A{\beta}40$) and by the 42 residue protein ($A{\beta}42$). While $A{\beta}40$ and $A{\beta}42$ differ in only two amino acid residues at the C-terminal end, $A{\beta}42$ is much more prone to aggregate and exhibits more neurotoxicity than $A{\beta}40$. Here, we investigate the molecular origin of the difference in the aggregation propensity of these two proteins by performing fully atomistic, explicit-water molecular dynamics simulations. Then, it is followed by the solvation thermodynamic analysis based on the integral-equation theory of liquids. We find that $A{\beta}42$ displays higher tendency to adopt ${\beta}$-sheet conformations than $A{\beta}40$, which would consequently facilitate the conversion to the ${\beta}$-sheet rich fibril structure. Furthermore, the solvation thermodynamic analysis on the simulated protein conformations indicates that $A{\beta}42$ is more hydrophobic than $A{\beta}40$, implying that the surrounding water imparts a larger thermodynamic driving force for the self-assembly of $A{\beta}42$. Taken together, our results provide structural and thermodynamic grounds on why $A{\beta}42$ is more aggregation-prone than $A{\beta}40$ in aqueous environments.

• Journal of Information Science Theory and Practice
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• 제1권3호
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• pp.60-73
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• 2013

The Database Industry Promotion Act was proposed at the National Assembly plenary session on July 26, 2012 and since then it has been in the process of enactment in consultation with all the governmental departments concerned. The recent trend of economic globalization and smart device innovation suggests a new opportunity and challenges for all industries. The database industry is also facing a new phase in an era of smart innovation. Korea is in a moment of opportunity to take an innovative approach to promoting the database industry. Korea should set up a national policy to promote the database industry for citizens, government, and research institutions, as well as enterprises. Above all, the Database Industry Promotion Act could play a great role in promoting the social infrastructure to enhance the capacity of small and medium-sized enterprises. This article discusses the background of the development of the Database Industry Promotion Act and its legislative processes in order to clarify its legal characteristics, including the meaning of the act. In addition, this article explains individual items related to the overall structure of the Database Industry Promotion Act. Finally, this article reviews the economic effects of the database industry for now and the future.

• 디자인학연구
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• 제4권1호
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• pp.61-73
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• 1991

The exhibition activity that a company is rendering to their consumers for the purpose of advertisement, sales promotion and enhancement of company inage get more and more internationalized and specialized. A company is changing from mass production system to small quantity production of various kinds to meet consumer's individualization and differentiation. Also, a company is experiencing a major change in their marketing strategy. As the society is entering on Information Age, the contents that a company intends to give consumer may be different individually. If a consumer is informed wrong information of the goods, a company needs a place to meet consumer face to face where the consumer feels and understands the substance of the goods. This is the current characteristics of Exhibition Media. Based on the result of the current Special Exhibition home and abroad along with background and characteristics of special Exhibition, this study sets a following task reflecting the general trend of social, cultural and economic atmosphere. First, Current Exhibition Industry will be diversified into more Specialized Exhibition, while our Exhibition Industry is very shaky under severe international competition. Also, Exhibition Plan that involves with architecture, interior, graphic, industrial design and advertisement, etc., needs international competitiveness while enhancing identity of Exhibition Plan along with comprehensive marketing strategy in the future. Second, Among most of the local special Exhibitions which invite the general public are normally invited for company public relation contrary to those of U.S.A. and Europe. This signifies of our industrial and social structure's by-product. As the future exhibition become Information Com$$\mu$ication Exhibition which requires specialized technical explanation, the correct description of the goods should be set as a Judgement basis of Exhibition Plan. Third, In parallel with increase of the Exhibition, the equipment expenses of a company goes up continuously. In view of this, a study $$\mu$t be oriented for re-use and curtailment of expenditure of those equipment. Also, as the use of Assembly System B on the rise as a result of diversification of special Exhibition, a study on the development of new material & design for Exhibition Equipment only B required.