• 대한기계학회논문집A
• /
• 제21권11호
• /
• pp.1765-1772
• /
• 1997

The layered composites have a character to change of structure stiffness with respect to the layup angles. The deformations in the fan-blades to be initially designed by considering efficiency and noise, etc., which arise due to the pressure during the fan operation, can make the fan inefficient. Thus, so as to minimize the deformations of the blades, it is needed to increase the stiffness of the blades. An investigation has been performed to develop the three dimensional layered composite shell element with the drilling degree of freedom and the optimization module for finding optimal layup angles with sensitivity analysis. And then they have been verified. In this study, the analysis model is engine cooling fan of automobile. In order to analyzes the stiffness of the composite fan blades, finite element analysis is performed. In addition, it is linked with optimal design process, and then the optimal angles that can maximize the stiffness of the blades are found. In the optimal design process, the deformations of the blades are considered as multiobjective functions, and this results minimum bending and twisting simultaneously.

• 한국정밀공학회지
• /
• 제32권9호
• /
• pp.825-831
• /
• 2015

In this paper, capture motion and visual information from a virtual reality luge simulator to analyze muscular activity in the lower limbs. The Luge Simulator consists of a motion platform with a pneumatic module for weight distribution. We recruited luge athletes and healthy subjects and made real-time surface EMG measurements to estimate the muscular activity in the lower limbs according to the motion protocol of a simulator, and a test was conducted for each subject. The results indicated that the rectus femoris had the highest muscular activity according to the level of the slope and velocity of the luge. The soleus muscle showed a high level of activity during a turn in the luge according to the direction. We found that the development of a virtual reality sports simulator based on physical reaction results could bring positive effects to optimize reality and human cenesthesia.

• 한국소음진동공학회논문집
• /
• 제17권8호
• /
• pp.673-682
• /
• 2007

Recently the trend of automobile industry is that IQS evaluation index against a sensitivity quality is increasing. To reduce rattle noise due to speaker sound at low frequencies, it is required the advanced technology analysis process of body structure. This paper optimized the design parameters of package tray panel according to the theoretical background about robust design and suggested the design guideline for resonance avoidance and the reduction of vibrational sensitivity considering the excitation frequency of woofer speaker. And this paper described the design process of a door module panel through the sensitivity analysis in case of the door speaker excitation. Finally, the analysis of the quality deviation using mother car is suggested to guarantee the stable characteristics of vehicle vibration in the early stage of vehicle development. These improvements can lead to shortening the time needed to develop better vehicles.

• 한국생산제조학회지
• /
• 제19권6호
• /
• pp.847-851
• /
• 2010

It was attempted to develop an auto part by over molding injection mold that produces precision products in high productivity with use of an eco-friendly TPE substitute material for NBR. NBR is currently used in motor gear cover, one of the key parts in motor module for auto doors. Gear cover is composed of plastics and rubber mostly today, which requires a two (2) step process for production using two presses of different types. A hot press is used at this time for forming the rubber, which has drawback of requiring a rather long forming time of 400 seconds for one forming process. Even though this difficulty is overcome by reducing production time through employment of multi-cavity molds, time for forming process must be shortened for improvement of the productivity eventually, and the existing method of insert injection for products that have been formed with plastic material must be outgrown. In this point of view, over molding injection using TPE has a big advantage. Forming time is shortened to 54 seconds, and working the two (2) processes in series by one (1) press could solve the durability problem caused by deflection of the plastics, not to mention shortening the process time. Enhancement of productivity by almost 80% and improvement in the accuracy of the product could thus be achieved.

• 한국산학기술학회논문지
• /
• 제11권1호
• /
• pp.13-20
• /
• 2010

본 연구의 목적은 Display 산업의 중요성에 주목하여 옥외 광고를 위한 LCD 패널용 콘솔(이하 'LCD 콘솔'이라 한다.)을 개발하는데 있다. 본 연구의 핵심 과제는 LCD 콘솔의 내부온도를 제어할 수 있도록 해주는 냉각시스템(Cooling System)을 개발하는 것이다. 냉각시스템은 상용화되어 있는 냉각휀(Cooling Fan), 히트싱크(Heat sinks), 열전소자(Thermo Electronic Module) 등의 제품들을 시스템적으로 통합시키는 응용기술로서 통계적 검정기법을 적용하여 개발되었다. 본 연구는 먼저 냉각시스템을 설계/제작한 후 실험을 통하여 냉각시스템 제어에 필요한 인자들의 설정 값들을 구하는 과정을 보였다. 이어서 개발된 냉각시스템을 이용하여 46인치 LCD Panel이 탑재된 LCD 콘솔을 설계/제작하고 실험을 통하여 완성품 LCD 콘솔의 성능을 확인하는 과정을 보였다.

• 멤브레인
• /
• 제23권2호
• /
• pp.129-135
• /
• 2013

도장공정에서 발생되는 휘발성 유기화합물의 회수를 위하여 중공사 분리막 모듈을 이용한 공정을 준비하여, 공급압력과 시간변화에 따른 휘발성 유기화합물의 회수에 대한 특성평가를 실시하였다. 중공사 분리막 모듈을 도장공정에 직접 적용한 결과, 투과된 휘발성 유기화합물의 농도는 투과시간과 압력의 증가됨에 따라 증가되었으며, 단일공정보다 다단공정이 더 우수한 분리성능을 나타내는 것을 확인하였다.

• 한국정보처리학회논문지
• /
• 제4권8호
• /
• pp.2025-2037
• /
• 1997

대화체 음성언어번역시스템의 일부인 개념기반 번역시스템은 음성인식의 결과를 이용하여 다른 언어로 번역해 주는 시스템이다. 본 논문은 여행계획 영역에 대해 한국어를 해석하여 영어, 일본어, 한국어로 번역해 주는 시스템에 대해 기술한 것이다. 개념기반 번역은 비정형 문장이 많은 대화체 문장을 처리하기 위해 형태소 분석 등의 구문정보를 이용하지 않고, 의미단위의 번역을 시도한 것으로 화자의 의도를 정확히 번역해 주는 것을 목표로 한다. 개념기반 번역은 280여개의 개념과 개념간의 계층구조에 의해, 인식결과를 개념구조로 변환한 후 다른 언어로 생성해 준다. 효율적인 한국어 처리를 위해 기준단어를 이용한 토큰분리기와 문법자동 수정기를 개발하였다. 그리고 자연스러운 생성문을 위해 각 언어에 대한 후처리기를 개발하였다.

• 한국소음진동공학회논문집
• /
• 제22권6호
• /
• pp.550-555
• /
• 2012

Among the various elements affecting a customer's evaluation of automobile quality, buzz, squeak and rattle(BSR) have been considered to be major factors. In most vehicle manufacturers, the BSR problems are solved by find-fix method with the vehicle road test, mainly due to various excitation sources, complex generation mechanism and subjective response. To systematically tackle the BSR problems in early stage of the vehicle development cycle, these difficulties should be resolved. The aim of the present paper is to characterize the sound quality property of BSR noise that can be used to assess the subjective responses to BSR. The four sound metrics from Zwicker's sound quality parameter are computed for the signals recorded for eight BSR noise source regions localized by using the acoustic-field visualized results. Then, the jury test of BSR noise are performed. On the basis of the computed sound metrics and jury test result is evaluated to represent the harshness of BSR noise. It is expected that the developed BSR measuring system and sound quality properties can be used to reduce the automotive interior BSR noise in terms of subjective levels as well as objective levels.

• 한국기계가공학회지
• /
• 제21권6호
• /
• pp.36-43
• /
• 2022

Automobile brake discs are a major part of automobiles that are directly related to driver safety, and prevention of judder and squall noise is very important. This phenomenon occurs for complex reasons such as the precision and assembly of the brake module, and the material of the brake disc. The purpose of this study is to analyze the effect of the grinding wheel's grain size on the grinding conditions when machining cast iron, the material of the brake disc, and to derive the optimal grinding conditions through this.

• 한국염색가공학회지
• /
• 제35권1호
• /
• pp.29-41
• /
• 2023

This study is about a hybrid lightweight cowl crossbeam structure with high rigidity and ability to absorb collision energy to support the cockpit module, which is an automobile interior part, and to absorb energy during a collision. It is a manufacturing process in which composite material bracket parts are inserted and injected into existing steel bars. When considering the mounting condition of a vehicle, the optimization of the fastening condition of the two parts and the mechanical properties of the composite material is acting as an important factor. Therefore, this study is about a composite material having a volume content of Polyamide(PA) and Glass Fiber used as a composite material for a composite material-metal hybrid cowl crossbeam. As a result of analyzing the physical properties of the PA/GF composite material, experimental data were obtained that can further enhance tensile strength and flexural strength by using PA66 rather than PA6 used as a base material for the composite material. And based on this, it contributed to securing the advantage of lightening by using high-stiffness composite material by improving the high disadvantage of the weight of the cowl crossbeam material, which was made only of existing metal materials.