http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Application of Operatig Window to Robust Process Optimization of Sheet Metal Forming
Kyungmo Kim(김경모),Jeong Je Yin(인정제),Yong S. Suh 한국기계가공학회 2009 한국기계가공학회지 Vol.8 No.4
It is essential to embed product quality in the design process to win the global competition. Many components found in many products including automobiles and electronic devices are fabricated using sheet metal forming processes. Wrinkle and fracture are two types of defects frequently found in the sheet metal forming process. Reducing such defects is a hard problem as they are affected by many uncontrollable factors. Attempts to solve the problem based on traditional deterministic optimization theories are often led to failures. Furthermore, the wrinkle and fracture are conflicting defects in such a way that reducing one defect leads to increasing the other. Hence, it is a difficult task to reduce both of them at the same time. In this research, a new design method for reducing the rates of conflicting defects under uncontrollable factors is presented by using operating window and a sequential search procedure. A new SN ratio is proposed to overcome the problems of a traditional SN ratio used in the operating window technique. The method is applied to optimizing the robust design of a sheet metal forming process. To show the effectiveness of the proposed method, a comparison is made between the traditional and the proposed methods using simulation software, applied to a design of particular sheet metal forming process problem. The results show that the proposed method always gives a more robust design that is less sensitive to noises than the traditional method.
Kyungmo Park,Youngkwon Lim,Doug Young Suh [Institute of Electrical and Electronics Engineers 2016 IEEE transactions on broadcasting Vol.62 No.1
<P>MPEG-2 transport stream (TS), standardized by the ISO/IEC as part of the well-known MPEG-2 standards family, is the most widely deployed standard for multimedia services in traditional broadcast industry, such as ATSC and DVB-T. MPEG standards have been designed to specify essential features for multimedia broadcast applications, such as the structure of multimedia content composed of multiple audio-visual streams and temporal relationships among those streams. One of the new MPEG standards that was recently developed and published, namely MPEG media transport (MMT), has catered for the emerging convergence of digital broadcasting and the Internet. MMT inherits major advantageous features of MPEG-2 TS and adds advanced and innovative features to support broadcast services in the new converged environment. IP-based broadcast standards, e.g., ATSC 3.0, has gained significant attention by the broadcast industries as IP-based broadcast provides more flexible and enriched multimedia broadcast services to users. The ATSC 3.0 has adopted MMT as its one of media delivery technology to strengthen hybrid delivery of multimedia services which could be consumed on multiple devices simultaneously. This paper discusses the use of MMT in ATSC 3.0 service delivery. Important features of MMT will be described together with their restrictions and extensions that are needed to enable efficient delivery of ATSC 3.0 services.</P>
Kyungmo Sung,Seonghoon Jo,Jaewook Lee,Jeong Hoan Park,Young Hoon Park,Jeongjoo Moon,Sung June Kim,Joonsoo Jeong,Jonghwan Lee,Kyungsik Eom 대한의용생체공학회 2023 Biomedical Engineering Letters (BMEL) Vol.13 No.2
Heating nanoparticles with a magnetic field could facilitate selective remote control of neural activity in deep tissue. However,current magnetothermal stimulation approaches are limited to single-channel stimulation. Here, we investigated variousdesigns for multichannel magnetothermal stimulation based on an array of resonant coils that are driven by a single loop coil. Using a tuning capacitor that allows resonant coils to resonate at the operating frequency, each coil’s ON and OFF resonancecan be controlled, enabling us to select stimulation channels. We found that smaller inner diameters of resonant coils producemore localized magnetic fields while larger coils produce magnetic fields over a longer distance. The constructed multichannelresonant coil arrays can provide a high enough magnetic field intensity to raise the temperature of nanoparticles by 8 °Cwhen we apply 35.2 W into the loop coil that is spaced 1 mm from the target neurons. This multichannel stimulation usinga simple resonant circuit approach would be useful for clinical applications of magnetothermal neural stimulation.