• Korean Journal of Plant Taxonomy
• /
• v.39 no.2
• /
• pp.120-123
• /
• 2009

A naturalized species from Korean flora, Cymbalaria muralis P. Gaetrn. (Scrophulariaceae), is firstly recorded from a well-drained bare field at Bulgwang-dong, Eunpyong-gu, Seoul city. The genus Cymbalaria Hill has not recorded in Korea and C. muralis is easily distinguished from the other species of Scrophulariaceae by palmately-lobed leaves, vine-like stems and cylindrical spur at the base in its flower. The new Korean name is 'Deong-gul-he-ran-cho'. Descriptions, illustrations and photographs of this species are given.

• Journal of the Korea Institute of Information and Communication Engineering
• /
• v.15 no.4
• /
• pp.935-942
• /
• 2011

This study aims to design and implement the finger gesture recognizing system that automatically recognizes finger gestures input through a camera and controls the computer. Common CCD cameras were redesigned as infrared light cameras to acquire the images. The recorded images go through the pre-process to find the hand features, the finger gestures are read accordingly, and an event takes place for the follow-up mouse controlling and presentation, and finally the way to control computers is suggested. The finger gesture recognizing system presented in this study has been verified as the next-generation interface to replace the mouse and keyboard for the future information-based units.

• Proceedings of the KIEE Conference
• /
• 2007.04a
• /
• pp.219-221
• /
• 2007

Recent changes to ubiquitous computing requires more natural human-computer(HCI) interfaces that provide high information accessibility. Hand-gesture, i.e., gestures performed by one 'or two hands, is emerging as a viable technology to complement or replace conventional HCI technology. This paper deals with hand-posture recognition. Hand-posture database construction is important in hand-posture recognition. Human hand is composed of 27 bones and the movement of each joint is modeled by 23 degrees of freedom. Even for the same hand-posture,. grabbed images may differ depending on user's characteristic and relative position between the hand and cameras. To solve the difficulty in defining hand-postures and construct database effective in size, we present a method using a 3D hand model. Hand joint angles for each hand-posture and corresponding silhouette images from many viewpoints by projecting the model into image planes are used to construct the ?database. The proposed method does not require additional equations to define movement constraints of each joint. Also using the method, it is easy to get images of one hand-posture from many vi.ewpoints and distances. Hence it is possible to construct database more precisely and concretely. The validity of the method is evaluated by applying it to the hand-posture recognition system.

• Applied Microscopy
• /
• v.32 no.1
• /
• pp.57-66
• /
• 2002

The structures of sucker of two Cobiidae; Common freshwater goby and Triden goby were observed by light and electron microscopy. Scanning electron microscopy revealed the characteristic narrow ridges and grooves on the apical portion of sucker of Common freshwater goby, and hexagonal structures similar to a honeycomb representing the intercellular junctional area on the middle and basal portions. Some ridges were present on the epithelial surface on the middle and basal portions. The openings of several mucus-secreting cells were present between main epithelial cells. Light and transmission electron microscopy revealed the core of the fin; soft rays with a surrounding dense collagen fiber layer. Some loosely arranged fibers (collagen fiber) radiated toward the surface epithelium. The surface epithelium was cuboidal or columnar in shape. Scanning electron microscopy revealed the coiled irregular ridges and grooves, which was less developed and had sparser distribution than in Common freshwater goby, on the apical portion of sucker of Triden goby. The middle and basal portions had honeycomb structures as in Common freshwater goby. Fewer mucoussecreting cells were present. Light and transmission electron microscopy showed the core of soft rays, dense collagen fiber layer, however, the radiating fibers observed in the Common freshwater goby was rarely present. The sucker was thinner because the epithelium is squamous or polygonal in shape and rare presence of the radiating fibers.

• Journal of the Korea Computer Graphics Society
• /
• v.26 no.3
• /
• pp.9-19
• /
• 2020

With the recent development of various kinds of virtual reality devices, there has been an active research effort to increase the sense of reality by recognizing the physical behavior of users rather than by classical user input methods. Among such devices, the Leap Motion controller recognizes the user's hand gestures and can realistically trace the user's hand in a virtual reality environment. However, manipulating an object in virtual reality using a recognized user's hand often causes the hand to pass through the object, which should not occur in the real world. This study presents a way to build a visual feedback system for enhancing the user's sense of interaction between hands and objects in virtual reality. In virtual reality, the user's hands are examined precisely by using a ray tracing method to see if the virtual object collides with the user's hand, and when any collision occurs, visual feedback is given through the process of reconstructing the user's hand by moving the position of the end of the user's fingers that enter the object through sign distance field and reverse mechanics. This enables realistic interaction in virtual reality in real time.

• Journal of the Korean Institute of Intelligent Systems
• /
• v.26 no.2
• /
• pp.147-152
• /
• 2016

Shape Memory Alloys (SMAs) undergo changes in shape and hardness when heated or cooled, and do so with great force. Since wire-type SMAs contract in length when heated and pull with a surprisingly large force and move silently, they can be used as actuactors which replace motors. These SMA actuators can be heated directly with electricity and can be used to create a wide range of motions. This paper presents the mechanical design and control for a three fingered, six degree-of-freedom robotic hand actuated by SMA actuators. Each finger has two joints and each joint is actuated with two tendons in the antagonistic manner. In order to create the sufficient force to make the smooth motion, the tendon is composed of two SMA actuators in parallel. For controlling the current to heat the SMA actuators, PWM drivers are used. In experiments, the antagonistic interaction of fingers are evaluated.

• Proceedings of the Korean Information Science Society Conference
• /
• 2011.06b
• /
• pp.237-239
• /
• 2011

기존의 오선지를 이용하여 음악을 시각적으로 표현하는 방법은 오선 기보법에 익숙하지 않은 일반 사용자들이 많은 양의 음악적 지식을 습득해야 한다는 제약을 가지고 있다. 현재는 이러한 한계를 개선한 직관적인 음악 표기법 중에서 피아노 롤 표기법이 많이 사용되고 있으나 모바일 환경에서는 단말기 화면 크기의 제약으로 인해 사용자가 원하는 위치에 정확히 음표를 입력하기 불편하다는 문제가 있다. 따라서 모바일 환경에서는 사용자가 월하지 않는 부정확한 입력이 이뤄졌을 경우 빠른 수정이 가능한 직관적인 인터랙티브 인터페이스가 요구된다. 따라서 본 논문에서는 옥타브 줌인/아웃과 함께 기존의 피아노 롤 표기법에서 사용되는 음표를 막대 모양으로 변형시켜 이를 사용자가 터치 앤드래그하여 입력할 수 있는 모바일용 음표 입력 인터페이스를 제안한다.

• Review of KIISC
• /
• v.12 no.2
• /
• pp.34-40
• /
• 2002

컴퓨터와 유\ulcorner무선 인터넷이 확산되어 더욱 보안의 중요성이 요구되면서 살아있는 개별 인간의 신체 일부를 이용한 생체인증 보안기술이 핫 이슈로 회자되고있다. 지문인증, 얼굴인증, 홍채인증, 정맥인증, DNA 인증, 뇌파인증, 손금/손모양인증, 음성인증, 서명인증 등 많은 생체인식기술들은 이미 수십 년 전부터 연구되었고, 과거 한때 상품화도 되었으나 시대의 요구에 부응하지 못하고 사라졌지만, 최근 들어서는 더욱 활발한 연구가 진행되고 있고 다양한 영역에서 상용화가 된 상태이다. 본 서명인증 보안기술은 전자펜(혹은 마우스)으로 입력된 개인의 동적인 서명을 이용하는 것으로써, 쓰는 모양, 쓰는 속도, 필체의 각도, 획수, 획순서, 펜DOWN/UP 정보 등의 여러 가지 정보를 비교\ulcorner분석하여 진서명인지 모조서명인지를 실시간으로 검증하는 것이다. 경제성, 보안성, 활용성, 안정성, 편의성 등의 여러 가지 관점에서 볼 때, 앞으로 널리 확산될 전망이다. 본 논문에서는 지난 10여 년간 직접 연구 개발하여 2000년 8월에 교수실험실창업으로 사업화한 서명기술의 개요와 응용/구축사례를 소개하고자 한다.

• Journal of the Korean Society for Precision Engineering
• /
• v.16 no.2 s.95
• /
• pp.130-137
• /
• 1999

In this paper we propose a method of determining the local curvature of a three dimensional convex object using the force and torque information obtained from the active touch of a robot hand. A technique for estimating two dimensional curvature of a convex object are introduced and the way of computing the three dimensional curvature from the two dimensional vurvatures is presented. Also, we develop an experimental system consisting of a finger and verify the effectiveness of the proposed method experimentally.

• Proceedings of the Korean Nuclear Society Conference
• /
• 1998.05b
• /
• pp.433-438
• /
• 1998

수소와 물 사이의 촉매교환공정은 중수 생산 및 삼중수소 분리를 위해 개발되어 왔다. 국산 소수성 촉매를 이용하여 새로운 튜브형 촉매탑을 고안하고, 수소와 물 사이의 수소 동위원소 분리를 실증하는 실험을 수행하였다. 국산 소수성 측매는 Styrene Divinyl Benzene Copolymer 담체에 백금을 담지한 촉매로써, 모양은 실린더형이며, 직경이 4mm이다. 촉매 작용을 하지 않는 충전물은 wire mesh ring(3mmx3mm)이고, 튜브는 PCI사 membrane(PVDF)이다. 촉매합의 직경은 2.5cm, 높이는 35cm였고, 온도는 333k, 압력은 0.1MPa였다. 기상 촉매반응만 시켰을 때 촉매탑이 정상상태에 도달되는데 약 3-5시간이 필요했으며, 액체 흐름이 있는 경우가 훨씬 짧았다. 촉매탑의 분리성능을 평가하기 위해 수소 동위원소 분리실험에서 얻은 기체 농도를 이용하여 물질전달계수(Kya)를 계산하였다. Kya는 0.2-0.5 sec$^{-1}$였으며, 액체와 기체 유속에 의해 크게 영향을 받았다.