• International Journal of Quality Innovation
• /
• 제6권3호
• /
• pp.204-215
• /
• 2005

This paper explores innovative manufacturing processes, which can be used to manufacture the national musical instrument of Trinidad and Tobago, the Musical Steel Drum or Steel Pan. The main manufacturing process used today is the manual hand-forming technique. In order to achieve more consistent and deeper formed components while maintaining the high quality of the instrument, it is proposed that the Marforming process and the Flow-forming process, an adaptation of the Spinforming process, be used more frequently in the future to replace the traditional Hand-forming method. In the traditional Spinforming technique material is pushed from the outer circumference of the metal disc to the center in progressive passes of the former. This results in a thinning of the outer region of the formed component with thickening of the center, however the opposite is required for the musical steel drum and by adapting the process the required strain distributions were achieved. Evaluation took the form of strain analyses of pre-formed steel drums and visual inspection of the quality of the surface finish. It was found that the Marformed components had the smallest range of strain values while the Spinformed components had the largest range.

• 인터넷정보학회논문지
• /
• 제7권5호
• /
• pp.33-41
• /
• 2006

제 4 세대 이동 통신망 SB12K(Systems Beyond IMI 2000)의 사용화가 예상되고 무선 랜 사용자의 이동서비스(mobile service) 요구가 증가됨에 따라 단말기의 이동성(mobility)을 지원하는 새로운 인증 방법이 요구된다. 무선 랜은 전파라는 전송매체를 사용하기 때문에 보안에 취약하다. 현재 무선 랜의 보안기능을 일관성 있게 제공하는 기술로 WPKI (Wireless Public Key Infrastructure)가 있다. WPKI는 인증서 사용이 필수적인데, 이것은 인증서 검증 및 CRL검색으로 인하여 핸드오프 성능에 많은 부담으로 작용된다. 본 논문에서는 무선 랜의 안정적인 이동 서비스를 위해 WPKI의 기술을 사용하면서 핸드오프에 영향을 주지 않는 기법을 제시한다. 제시한 기법은 통신 데이터의 암호화에 필요한 비밀 키를 단말과 로밍 서버가 선행하여 습득하는 것이다.

• 한국지능시스템학회논문지
• /
• 제14권4호
• /
• pp.506-511
• /
• 2004

최근 몇 년 동안 사람들의 고유한 생리적인 특징을 이용한 생체 인식은 새로운 학문으로서 연구 및 개발이 활발하게 진행되고 있다. 지금까지, 오로지 지문 인식만이 다른 생체 인식에 비해 확인과 식별 시스템들이 더 정교하고, 비싼 취득 인터페이스들과 인식 과정을 필요로 하기 때문에 온라인 보안 검사를 위하여 한정된 성공을 보았다. Hand-Geometry는 생체 인식의 확인 그리고 취득의 편리 때문에 식별 그리고 확인을 위하여 사용되고 있다. 그러므로, 본 논문은 이러한 특징을 가지는 손의 기하학적인 Hand-Geometry 인식 시스템을 제안하고자 한다. 해부학적인 관점에서, 인간의 손은 길이, 폭, 두께, 기하학적인 모양, 손바닥의 모양, 그리고 손가락들의 기하학적인 모양까지 특성으로 나타내어질 수 있다. 본 논문에서 제안한 Hand-Geometry 인식 시스템은 30개의 특징 데이터를 가진다. 그러나 특징 데이터 가운데 사용자의 Hand-Geometry의 특징에 따라 길이 데이터가 변하는 것을 실험적으로 발견하였다. 따라서 이와 같은 가변적인 길이 데이터를 안정화시키기 위하여 본 논문에서는 길이 데이터의 기준점을 손톱 아래 점으로 정하고, GA를 적용하여 보다 안정된 특징점을 추출하였다.

• Clinical and Experimental Pediatrics
• /
• 제53권2호
• /
• pp.129-135
• /
• 2010

Human rhinoviruses (HRVs) is a nonenveloped, single stranded RNA virus belonging to the family Picornavirudae. Transmission by direct contact such as hand-to-hand, hand-to-nose, and hand-to-eye has been readily demonstrated in experimental settings. HRV are the most frequent causes of common cold infection, however, they are also known to replicate in the lower respiratory tract and associated with more severe respiratory illnesses such as asthma. New technique such as reverse transcriptase polymerase chain reaction and molecular typing in HRV has been developed and our understanding of the importance of these respiratory viruses. HRVs consisted of 101 serotypes that are classified into groups A and B according to sequence variations. And there is a newly identified set of HRVs, called Group C, and it is currently under investigation. In recent study using PCR techniques, HRVs accounted for approximate 50-80% of common colds and 85 % of childhood asthma exacerbations and in more than half of adult exacerbations. However, the mechanisms of HRV- induced asthma exacerbations are poorly understood. This review discusses the association between HRVs and childhood asthma.

• 대한임베디드공학회논문지
• /
• 제16권1호
• /
• pp.17-27
• /
• 2021

In this paper, we develop a galaxy image classification method based on hand-crafted features and machine learning techniques. Additionally, we provide an empirical analysis to reveal which combination of the techniques is effective for galaxy image classification. To achieve this, we developed a framework which consists of four modules such as preprocessing, feature extraction, feature post-processing, and classification. Finally, we found that the best technique for galaxy image classification is a method to use a median filter, ORB vector features and a voting classifier based on RBF SVM, random forest and logistic regression. The final method is efficient so we believe that it is applicable to embedded environments.

• 전력전자학회:학술대회논문집
• /
• 전력전자학회 2002년도 전력전자학술대회 논문집
• /
• pp.330-333
• /
• 2002

The design of high power electronic circuits and the verification of the design by practical experiments are time and cost consuming. Recently power circuit simulation technique is developing to do it easily. However, most of the simulation has used the ideal switch model consists of passive component that can not describe the physical characteristics of semiconductor devices and cannot describe the switching transient state. For the design of such power electronic circuits by the simulation, the switching transients are very important. Therefore the simulation models must describe the switching transient and the stationary behavior as precisely as possible on the hand and as fast as possible the other hand. This paper introduces the application of the physical models of power devices that are developed by TUM(Technical University of Munich, Germany) for the power electronic circuit analysis.

• Journal of Electrical Engineering and Technology
• /
• 제11권4호
• /
• pp.943-950
• /
• 2016

In this paper, we propose to analyze the physical characteristics of a planar dual-composite right-left handed transmission line by a common application of Bond Graph approach and Scattering formalism (Methodology S.BG). The technique, we propose consists, on the one hand, of modeling of a dual composite right-left metamaterial transmission line (D-CRLH-TL) by Bond Graph approach, and, it consists of extracting the equivalent circuit of this studied structure. On the other hand, it consists to exploiting the scattering parameters (Scattering matrix) of the DCRLH-TL using the methodology which we previously developed since 2009. Finally, the validation of the proposed and used technique is carried out by comparisons between the simulations results with ADS and Maple (or MatLab).

• Archives of Reconstructive Microsurgery
• /
• 제13권1호
• /
• pp.43-50
• /
• 2004

One of the major advantages of microsurgical reconstruction for defects of the hand is that these techniques allow for selection of the most ideal tissue to reconstruct a particular defect, thus optimizing the functional and aesthetic outcome. The dorsalis pedis free flap is an excellent reconstructive tool for various hand reconstructions. It has a reliable vasculature with vessels that are relative large on a long pedicle. It provides thin pliable tissue and be innervated by deep peroneal nerve. Coupled with its thinness and pliability, it is ideal for innervated cover of critically sensitive area, especially such as the hand. Thus it can be used as a cutaneotendinous flap, or an osteocutaneous flap. Otherwise, the major criticism with this flap is related to its uncertain vascularity and the donor defect. It is the purpose of this paper to outline our technique of flap elevation and donor site closure and to indicate our current use of this flap in hand reconstruction. We have treated 10 cases (6 burn scar contracture cases, 4 acute hand trauma cases) of hand reconstruction from Dec. 3, 1997 to Mar. 4, 2004 using dorsalis pedis free flap. The key points for sucess in terms of a viable flap and acceptable donor site are the preservation of the critical dorsalis pedis-first dorsal metatarsal vascular axis and the creation of a viable bed for grafting. In addition, we substituted preserved superficial fat skin graft for split thickness skin graft and wet environment was offered for good graft take. Preserved superficial fat skin is defined as composite graft containing epidermis, dermis and superficial fat layer. With sufficient care in flap elevation and donor site closure, a good graft take of preserved superficial fat skin under wet environment can be achieved with no functional disability and minimal cosmetic deformity in donor site. This flap has proved itself to be a best choice for hand reconstruction.

• 패션비즈니스
• /
• 제10권1호
• /
• pp.1-19
• /
• 2006

The purpose of this study is to investigate the social and cultural background of hand-knitting things with handcraft feeling which is appeared conspicuously after 2000. And to analyze the types and characteristics of hand-knit design. The resorts of this study is as follows: First, it is found that the pattern of stitch in their forms and ornament technique of handcraft feeling are the remarkable factors to decide the specific designs in the most of hand-knit designs. The major forms are plain stitch, rib stitch, cable stitch, lace stitch, relief stitch and pile stitch and the ornament techniques such as patch work, fringe, embroidery and collage are being widely used. Second, after 2000, due to peoples' preference for handcraft feeling manufactures, pursuit trend of artless luxury by retouch appeared, it made feeling for recurrence of the past and the warm humanity. In addition, the pro-eco trend using pro-environment materials and capturing the nature as images are on its way to advance. Through the mix & match of materials, details and items, it becomes possible to express many kinds of images. Thanks to those characteristics, the hand-knit designs are now acknowledged as luxurious with the couture sense attached and are shaking off their previous image of recycling.

• 한국공작기계학회논문집
• /
• 제15권5호
• /
• pp.14-20
• /
• 2006

In recent year, as the robot technology is developed, the researches on the artificial muscle actuator that enables robot to move dexterously like biological organ become active. Actuators are key technologies underpinning robotics. Breakthroughs in actuator technology, particular in terms of power-to-weight ratio, or energy-density, will have significant impacts upon the design and control of robotic system. In this paper, a new approach to design and control of shape memory alloy(SMA) actuator is presented to drive the robot hand. SMA wire is divided into many segments and their thermal states of the SMA are controlled individually in a binary manner. This control manner will reduce the hysteresis that the SMA material has and it becomes the fundamental technology to develop the anthropomorphic robot hand. In this paper, the mechanism In the digital step motor of the shape memory alloy that is driven by the segmented binary control, which is a new control technique, is studied. This SMA digital step actuator applies for the robot hand and the driving mechanism of the robot hand is investigated.