• 제어로봇시스템학회논문지
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• 제22권1호
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• pp.24-30
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• 2016

The accuracy of small and low-cost CCD cameras is insufficient to provide data for precisely tracking unmanned aerial vehicles (UAVs). This study shows how a quad rotor UAV can hover on a human targeted tracking object by using data from a CCD camera rather than imprecise GPS data. To realize this, quadcopter UAVs need to recognize their position and posture in known environments as well as unknown environments. Moreover, it is necessary for their localization to occur naturally. It is desirable for UAVs to estimate their position by solving uncertainty for quadcopter UAV hovering, as this is one of the most important problems. In this paper, we describe a method for determining the altitude of a quadcopter UAV using image information of a moving object like a walking human. This method combines the observed position from GPS sensors and the estimated position from images captured by a fixed camera to localize a UAV. Using the a priori known path of a quadcopter UAV in the world coordinates and a perspective camera model, we derive the geometric constraint equations that represent the relation between image frame coordinates for a moving object and the estimated quadcopter UAV's altitude. Since the equations are based on the geometric constraint equation, measurement error may exist all the time. The proposed method utilizes the error between the observed and estimated image coordinates to localize the quadcopter UAV. The Kalman filter scheme is applied for this method. Its performance is verified by a computer simulation and experiments.

• 한국정보통신학회논문지
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• 제8권2호
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• pp.499-508
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• 2004

스마트 홈이나 지능화된 홈 네트워크 제어 시스템이 거주자에 대한 자동화된 서비스를 제공하기 위해서 홈 디바이스들의 협업을 필요로 한다. 홈 디바이스들의 협업은 사용자의 제어 요구에 대해 같은 목적을 가지는 둘 이상의 홈 디바이스들을 동시에 제어하는 거주자를 위한 서비스로 정의할 수 있다. 홈 디바이스 협업의 대상이 되는 것은 흠 디바이스의 동작 객체이며, 이 객체들은 AHAM(Association of Home Appliance Manufactures) CHA(Connected Home Appliances)에 디바이스(가전기기) 모델 별로 정의되어 있다. AHAM의 CHA는 일반적인 가전기기 모델, 객체들과 상위 수준의 메시지들을 표현함으로써 네트워킹을 통해 가능한 서비스와 특징들을 활성화하고자 하고 있으나, 디바이스 모델의 객체간의 협업의 표현파 처리에 대해서는 고려되어 있지 않다. 본 논문은 홈 디바이스들 사이에서 발견할 수 있는 협업 관계를 정의하고, AHAM의 객체들이 협업 관계를 처리할 수 있는 협업 모델을 제안한다

• 한국정보과학회논문지:소프트웨어및응용
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• 제29권1_2호
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• pp.65-79
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• 2002

객체지향 프레임웍은 다수의 응용 소프트웨어의 개발에 반복적으로 재사용되므로 철저한 시험이 요구될 뿐만 아니라 재사용 시 확장된 프레임웍에 대해서도 추가적인 시험이 필요하다. 그런데 프레임웍은 개조, 합성된 확장 부위의 시험에 대한 제어와 관찰을 어렵게 하는 성질을 갖고 있다. 본 논문에서는 프레임웍을 개조, 확장하여 응용 프로그램을 구현할 때 발생할 수 있는 오류들이 시험을 통하여 효율적으로 발견될 수 있도록 프레임웍의 가변 부위에 테스터 컴포넌트들을 BIT(Built-in Test)로 내장하는 방법을 기술한다. 프레임웍에 이와 같이 내장된 테스터 컴포넌트들은 프레임웍의 시험 시 제어와 관찰을 용이하게 하여 프레임웍의 시험성을 높여준다. 여기서 제안된 방법으로 설계된 테스터 컴포넌트들은 시험대상 프레임웍의 확장 부위에 프레임웍 코드의 변경이나 간섭 효과가 없게 부착할 수 있고 필요에 따라 동적으로 탈착할 수 있다.

• Nutrition Research and Practice
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• 제9권5호
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• pp.480-488
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• 2015

BACKGROUND/OBJECTIVES: Alzheimer's disease (AD) is characterized by deficits in memory and cognitive functions. The accumulation of amyloid beta peptide ($A{\beta}$) and oxidative stress in the brain are the most common causes of AD. MATERIALS/METHODS: Caffeic acid (CA) is an active phenolic compound that has a variety of pharmacological actions. We studied the protective abilities of CA in an $A{\beta}_{25-35}$-injected AD mouse model. CA was administered at an oral dose of 10 or 50 mg/kg/day for 2 weeks. Behavioral tests including T-maze, object recognition, and Morris water maze were carried out to assess cognitive abilities. In addition, lipid peroxidation and nitric oxide (NO) production in the brain were measured to investigate the protective effect of CA in oxidative stress. RESULTS: In the T-maze and object recognition tests, novel route awareness and novel object recognition were improved by oral administration of CA compared with the $A{\beta}_{25-35}$-injected control group. These results indicate that administration of CA improved spatial cognitive and memory functions. The Morris water maze test showed that memory function was enhanced by administration of CA. In addition, CA inhibited lipid peroxidation and NO formation in the liver, kidney, and brain compared with the $A{\beta}_{25-35}$-injected control group. In particular, CA 50 mg/kg/day showed the stronger protective effect from cognitive impairment than CA 10 mg/kg/day. CONCLUSIONS: The present results suggest that CA improves $A{\beta}_{25-35}$-induced memory deficits and cognitive impairment through inhibition of lipid peroxidation and NO production.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1989년도 한국자동제어학술회의논문집; Seoul, Korea; 27-28 Oct. 1989
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• pp.781-785
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• 1989

In the field of control technology, too, it is about time that the students should free themseleves from the paradigm of Newtonian mechanics. Otherwise, they might fail to grasp the essence of control. Now, let us consider the essence of control. Control consists of manipulating a particular object, matter, energy of environment on the basis of certain medium information. (measurement data, force, etc.) So, we shall look into the methods of manipulation. Here, we consider natural control, constraining control, and hybrid control as basic methods of manipulation. In this paper, we would like to put forward the daring proposal that it's called a Holon-type hybrid control system. It is intended to control a plat with complicated or unknown characteristics where a conventional control theory is not easy to apply. A prototype system has been developed and applied to a real plant. The control system is a multi-layer system. Each layer includes different control input. The important features of the system are as follows: 1) Each layer behaves autonomously and also cooperates with each other to optimize the whole plant. 2) The controller optimizes a plant without mathematical models when these models are not easy to obtain.

• 정보처리학회논문지D
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• 제12D권6호
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• pp.829-836
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• 2005

정확한 객체 분류를 위한 분리 기준을 지정하기 위한 방법은 의사결정수들(decisions trees) 사이에 주요한 이슈이다. 이 논문은 최적의 분리 지점을 찾기 위해 분류에 대한 새로운 분리방법을 기술하고 있다. 모든 시작점 값들(threshold values)을 검색함으로 제공되는 기존의 분리방법들과 다르게, 이 논문에서는 미리 지정된 인터벌들의 확률을 기반으로 하는 분리방법을 제안하고 있다 제시한 방법은 사용자가 인터벌의 수를 조정함으로써 트리의 정확도를 통제할 수 있도록 할 수 있으며, 제기된 분리방법을 이미지 객체 인식하기 위한 특징추출을 수치화함으로써 검색되는 일련의 이미지 데이터에 적용하였다.

• 제어로봇시스템학회:학술대회논문집
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• 제어로봇시스템학회 1996년도 Proceedings of the Korea Automatic Control Conference, 11th (KACC); Pohang, Korea; 24-26 Oct. 1996
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• pp.409-412
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• 1996

Ultrasonic sensors are widely used in various applications due to advantages of low cost, simplicity in construction, mechanical robustness, and little environmental restriction in usage. But the main purposes of the noncontact sensing are rather narrowly confined within object detection and distance measurement. For the application of object recognition, ultrasonic sensors exhibit several shortcomings of poor directionality which results in low spatial resolution of objects, and specularity which gives frequent erroneous range readings. To resolve these problems in object recognition, an array of the sensor has been used. To improve the spatial resolution, more number of sensors are used in essence throughout the various devices of the sensor arrays. Under the disguise of a fixed number of the sensors, the array can be shifted mechanically in several steps. In this paper we propose a practical sensor resolution enhancement method using an electronic circuit accompanying the sensor array. The circuit changes the transmitter output voltage in several steps. Using the known sensor characteristics, a set of different return echo signals provide enhanced spatial resolution. The improvement is obtained with neither the cost of the increased number of the sensors nor extra mechanical devices.

• 자동차안전학회지
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• 제4권2호
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• pp.32-36
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• 2012

The Automatic unmanned target object carrying system (AUTOCS) is developed for testing road vehicle radar and vision sensor. It is important for the target to reflect the realistic target characteristics when developing ASV or ADAS products. The AUTOCS is developed to move the pedestrian or motorcycle target for desired speed and position. The AUTOCS is designed that only payload target which is a manikin or a motorcycle is detected by the sensor not the AUTOCS itself. In order for the AUTOCS to have low exposure to radar, the AUTOCS is stealthy shaped to have low RCS(Radar Cross Section). For deceiving vision sensor, the AUTOCS has a specially designed pattern on outside skin which resembles the asphalt pattern. The AUTOCS has three driving modes which are remote control, path following and replay. The AUTOCS V.1 is tested to verify the radar detect characteristics, and the AUTOCS successfully demonstrated that it is not detected by a car radar. The result is presented in this paper.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2004년도 추계학술대회 논문집
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• pp.1299-1302
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• 2004

A real object duplication system (RODS), including three dimensional (3D) scanner and solid freeform fabrication system (SFFS), is a device to make three-dimensional objects directly from the drawing or photo data. A Selective Multi-Laser Sintering (SMLS) process designed in this paper is by which computer images received using 3D scanner are built up from polymer powder on building room of large size using dual laser at industrial type SFF system. Using the process can rapidly produce real object duplication components of industrial type such as cylinder, engine block, chassis of automobile, etc. In this paper, the industrial type SFF system using SMLS process is manufactured and the system is satisfied with high precision and high speed processing technique. To research characteristics of each part for theindustrial type SFF system, a structure and thermal analysis and test of each part is carried out. Also, to achievement of high performance for industrial type SFF system, design and fabrication for the structure, heater, nitrogen supply, laser and control part are carried out.

• 한국정보과학회논문지:소프트웨어및응용
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• 제36권11호
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• pp.947-954
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• 2009

본 논문은 입력받은 다수 이미지의 Visual Hull을 이용하여 Surfel 기반의 물체를 복원하는 새로운 방법을 제안한다. Sufel은 포인트 집합면을 효과적으로 근사하여 나타내는 포인트 표현 단위이다. LDC(Layered Depth Cube) Surfel 샘플링 방식에 입력 이미지로부터 근사되는 형상을 대표하는 Visual Hull의 개념을 연동하여 이미지로부터 물체의 Surfel 기하 정보를 생성할 수 있다. Surfel 표현 방식은 기존의 폴리곤 기반 방식에 비해 상대적으로 적은 메모리를 소모하고 LDC 해상도를 자유롭게 바꿀 수 있기 때문에, 대상 물체를 복원하는 품질을 조절 가능하며, 주어진 메모리 자원에 대해서 최대의 품질을 가진 결과를 얻을 수 있다.