• 제어로봇시스템학회논문지
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• 제10권11호
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• pp.1028-1036
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• 2004

Ultrasonic sensors are widely used in mobile robot applications to recognize external environments by virtue that they are cheap, easy to use, and robust under varying lighting conditions. In most cases, a single ultrasonic sensor is used to measure the distance to an object based on time-of-flight (TOF) information, whereas multiple sensors are used to recognize the shape of an object, such as a comer, plane, or edge. However, the conventional sequential driving technique involves a long measurement time. This problem can be resolved by pulse coding of ultrasonic signals, which allows multi-sensors to be emitted simultaneously and adjacent objects to be distinguished. Accordingly, this paper presents a new simultaneous coded driving system for an ultrasonic sensor array for object recognition in autonomous mobile robots. The proposed system is designed and implemented. A micro-controller unit is implemented using a DSP, Polaroid 6500 ranging modules are modified for firing the coded signals, and a 5-channel coded signal generating board is made using a FPGA. To verify the proposed method, experiments were conducted in an environment with overlapping signals, and the flight distances fur each sensor were obtained from the received overlapping signals using correlations and conversion to a bipolar PCM-NRZ signal.

• The Plant Pathology Journal
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• 제34권5호
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• pp.445-450
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• 2018

Bacteriophages, bacteria-infecting viruses, have been recently reconsidered as a biological control tool for preventing bacterial pathogens. Erwinia amylovora and E. pyrifoliae cause fire blight and black shoot blight disease in apple and pear, respectively. In this study, the bacteriophage phiEaP-8 was isolated from apple orchard soil and could efficiently and specifically kill both E. amylovora and E. pyrifoliae. This bacteriophage belongs to the Podoviridae family. Whole genome analysis revealed that phiEaP-8 carries a 75,929 bp genomic DNA with 78 coding sequences and 5 tRNA genes. Genome comparison showed that phiEaP-8 has only 85% identity to known bacteriophages at the DNA level. PhiEaP-8 retained lytic activity up to $50^{\circ}C$, within a pH range from 5 to 10, and under 365 nm UV light. Based on these characteristics, the bacteriophage phiEaP-8 is novel and carries potential to control both E. amylovora and E. pyrifoliae in apple and pear.

• 한국인터넷방송통신학회논문지
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• 제16권5호
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• pp.105-110
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• 2016

현재, 국내 CNC 산업분야는 제조업의 패러다임 변화에 따라 공작기계에 첨단 기술의 적용이 활발하게 추진되고 있다. 즉, 공작기계의 제어를 담당하는 CNC의 IT화는 가장 중요한 부분을 차지하고 있다. 하지만 공작기계 분야에 모션제어 전문기술 부족의 가장 큰 이유는 PC기반의 컨트롤러의 경우 비중을 많이 차지하는 윈도우즈 언어를 사용하기 보다는 G-Code를 직접 좌표에 맞춰 코딩하거나 값비싼 외산 S/W를 통해 변환 하는 경우가 대부분이기 때문이다. 본 논문에서는 다양한 형태의 CAD 데이터를 손쉽게 G-Code 데이터로 변환할 수 있는 G-Code 변환 프로그램 및 CAD&CAM과 응용 소프트웨어를 개발하고 이 변환된 데이터를 바로 로봇을 통해 원하는 동작을 시킬 수 있는 전용 모션 컨트롤러를 구현한다.

• 생물환경조절학회지
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• 제1권1호
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• pp.37-51
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• 1992

Quantizing and extracting visual features of mushroom(Lentinus edodes L.) are crucial to the sorting and grading automation, the growth state measurement, and the dried performance indexing. A computer image processing system was utilized for the extraction and measurement of visual features of front and back sides of the mushroom. The image processing system is composed of the IBM PC compatible 386DK, ITEX PCVISION Plus frame grabber, B/W CCD camera, VGA color graphic monitor, and image output RGB monitor. In this paper, an automatic thresholding algorithm was developed to yield the segmented binary image representing skin states of the front and back sides. An eight directional Freeman's chain coding was modified to solve the edge disconnectivity by gradually expanding the mask size of 3$\times$3 to 9$\times$9. A real scaled geometric quantity of the object was directly extracted from the 8-directional chain element. The external shape of the mushroom was analyzed and converted to the quantitative feature patterns. Efficient algorithms for the extraction of the selected feature patterns and the recognition of the front and back side were developed. The developed algorithms were coded in a menu driven way using MS_C language Ver.6.0, PC VISION PLUS library fuctions, and VGA graphic functions.

• 드라이브 ㆍ 컨트롤
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• 제9권2호
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• pp.39-45
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• 2012

The NAS 1638 cleanliness classification system was originally developed in 1966 by the US Aircraft Industries of America to both simplify reporting of particle count data and to control the introduction of dirt during the assembly of aircraft fluid systems. The numbers of particles at stated sizes are represented by broad bands where the interval was generally a doubling of contamination. A number of systems have been introduced since this to suit differing requirements. NAS 1638 and AS4059 are used in other industrial sectors such as the Off-shore & Sub-Sea and the Primary Metal Industries. The changes to ISO contamination measurement standards controlled by ISO/TC131/SC6 in 1999 meant that a revision of most of these classification systems was necessary. The body responsible for NAS 1638 decided to withdraw it for new installations and replace it with an update of an existing standard, SAE AS 4059. This paper details the philosophy behind the contamination coding systems, the reasons for the changes to the ISO contamination standards and explains the workings of AS 4059, the replacement for NAS 1638. It goes on to detail the latest changes to this standard.

• KSII Transactions on Internet and Information Systems (TIIS)
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• 제10권12호
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• pp.5191-5211
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• 2016

It is essential to satisfy class-specific QoS constraints to provide broadband services for new generation networks. The present study proposes a QoS-driven multicast scheme for wireless networks in which the transmission rate and end-to-end delay are assumed to be bounded during a multiple multicast session. A distributed algorithm was used to identify a cost-efficient sub-graph between the source and destination which can satisfy QoS constraints of a multicast session. The model was then modified as to be applied for wireless networks in which satisfying interference constraints is the main challenge. A discrete power control scheme was also applied for the QoS-aware multicast model to accommodate the effect of transmission power level based on link capacity requirements. We also proposed random power allocation (RPA) and gradient power allocation (GPA) algorithms to efficient resource distribution each of which has different time complexity and optimality levels. Experimental results confirm that the proposed power allocation techniques decrease the number of unavailable links between intermediate nodes in the sub-graph and considerably increase the chance of finding an optimal solution.

• 한국정보통신학회:학술대회논문집
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• 한국정보통신학회 2013년도 추계학술대회
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• pp.946-948
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• 2013

베큘로바이러스 시스템이 제조되었는데 이것은 polyhedron promoter, vesicular stomatitis virus G (VSVG), polyA, cytomegalovirus (CMV) promoter, enhanced green fluorescent protein (EGFP), protein transduction domain (PTD) 유전자를 재조합한 것이다. 본 재조합벡터 시스템은 인간 섬유아세포에 적용하여 시험하였고 재조합된 유전자의 전이와 유전자 발현을 대조 벡터시스템과 비교하였다. 본 연구로부터 새롭게 제작된 본 베큘로바이러스 시스템이 유전자의 전이와 유전자 발현 면에서 대조 벡터시스템 보다 고효율을 나타내었다.

• 한국통신학회논문지
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• 제27권2A호
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• pp.165-172
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• 2002

MPEG-2 트랜스부호화기는 이미 부호화되어 있는 비트스트림의 비트율을 변경하는 것이다. 비트율제어를 위하여 기존의 제어 방식을 개선한 새로운 알고리듬을 제안하였으며 모의실험을 통해 임의의 비트율로 변경했을 때 우수한 성능을 보이는 것을 확인하였다. 비트율 제어에서는 비트스트립내의 정보를 이용하여 매크로블럭 단위의 비트율-양자화 파라미터 모델을 제안하였다. 이 모델은 DCT 계수를 사용하였기 때문에 화면의 종류에 관계없이 사용할 수 있었다. 비트율-양자화파라미터 모델의 정확도를 높이도록 매크로블럭의 활동도에 따른 구분도 하였다. 모의 실험결과, 특정 비트율을 가지는 비트스트림을 가지고 다른 비트율로 변환하였을 때 TM5로 재부호화 했을 때보다 제안한 방식이 더 높은 PSNR값과 제어 성능을 보였다. MPEG-2의 스케일러블 프로파일도 분석을 하였다. 그 결과 변환부호화기에는 적합하지 않다는 결과를 얻었다.

• Journal of Communications and Networks
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• 제13권5호
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• pp.421-427
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• 2011

Problems encountered in IEEE 802.11 medium access control (MAC) design are interferences from neighboring or hidden nodes and collision from simultaneous transmissions within the same contention floors. This paper presents the selective decoding schemes in MAC protocol for multiple input multiple output ad-hoc networks. It is able to mitigate interferences by using a developed minimum mean-squared error technique. This interference mitigation combined with the maximum likelihood decoding schemes for the Alamouti coding enables the receiver to decode and differentiate the desired data streams from co-channel data streams. As a result, it allows a pair of simultaneous transmissions to the same or different nodes which yields the network utilization increase. Moreover, the presented three decoding schemes and time line operations are optimally selected corresponding to the transmission demand of neighboring nodes to avoid collision. The selection is determined by the number of request to send (RTS) packets and the type of clear to send packets. Both theoretical channel capacity and simulation results show that the proposed selective decoding scheme MAC protocol outperforms the mitigation interference using multiple antennas and the parallel RTS processing protocols for the cases of (1) single data stream and (2) two independent data streams which are simultaneously transmitted by two independent transmitters.

• 한국정보통신학회논문지
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• 제18권8호
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• pp.2017-2022
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• 2014

폴리히드론 프로모터, 수포성구내염 바이러스G, 폴리A, 사이토메가바이러스 프로모터, 강화녹색형광단백질, 단백질전달부위 유전자 등을 포함한 새로운 베큘로바이러스 시스템이 제조되었다. 본 재조합벡터 시스템은 인간 섬유아세포에 적용하여 시험하였고 재조합된 유전자의 전달과 유전자 발현을 대조 벡터시스템과 비교하였다. 본 연구로부터 새롭게 제작된 본 베큘로바이러스 시스템이 유전자의 전이와 유전자 발현 면에서 대조 벡터시스템 보다 고효율을 나타내었다.