• 제목/요약/키워드: pattern direction

검색결과 1,502건 처리시간 0.024초

Analysis of spraying performance of agricultural drones according to flight conditions

  • Dae-Hyun Lee;Baek-Gyeom Seong;Seung-Woo Kang;Soo-Hyun Cho;Xiongzhe Han;Yeongho Kang;Chun-Gu Lee;Seung-Hwa Yu
    • 농업과학연구
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    • 제50권3호
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    • pp.427-435
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    • 2023
  • This study was conducted to evaluate the spraying performance according to the flight conditions of agricultural drones for the development of a variable control system. The analyzed flight conditions comprised six factors: spraying direction, flight speed, altitude, wind speed, wind direction, and rotor rotational speed. The ratio of the area sprayed on the water-sensitive paper was used as the coverage, and the distribution and amount of the coverage were evaluated. The coverage distribution based on the distance from the drone was used to evaluate a spray pattern, and the distribution was expressed as a Gaussian function approximation. In addition, the probability distribution based on coverage was expressed as the cumulative probability via Gamma function approximation to analyze the spraying efficiency in the target area. The results showed that the averaged coverage decreased significantly as the flight speed and wind speed increased, and the wind direction changed the spray pattern without a coverage decrease. This study contributes to the development of a control technique for the precision control system of agricultural drones.

목형의 엔드 밀링시 가공 특성에 관한 연구(I) (A Study on the Cutting Characteristics of Wood Patterns in End Milling(I))

  • 김성일
    • 한국공작기계학회논문집
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    • 제16권1호
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    • pp.53-59
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    • 2007
  • The cutting tests of wood patterns are carried out using CNC milling machine. The cutting forces are monitored to analyse the cutting process. The surface characteristics of machined surface are investigated at various cutting conditions such as cutting speed, feed speed, cutting direction of wood pattern and wood material. In the CNC end-milling, the surface roughness increases as feed speed increases and decreases as cutting speed increases. However, the cutting force and surface roughness are different along the cutting direction and material of wood pattern.

A Study on Mobile Target Estimation Resolution using Effects of Model Errors and Sensitivity Analysis

  • Lee, Kwan Hyeong
    • International journal of advanced smart convergence
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    • 제2권1호
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    • pp.21-23
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    • 2013
  • The antenna pattern in this case has a main beam pointed in the desired signal direction, and has a null in the direction of the interference.The conventional antenna pattern concepts of beam width, side lobes, and main beams are not used, as the antenna weights are designed to achieve a set performance criterion such as maximization of the output SNR.A new direction of arrival estimation method using effects of model errors and sensitivity analysis is proposed. Two subspaces are used to form a signal space whose phase shift between the reference signal and its effects of model error signal. Through simulation, the performance showed that the proposed method leads to increased resolution and improved accuracy of DOA estimation relative to those achieved with existing method. Since a desired signal is obtained after interference rejection through correction effects of model error, the effect of channel interference on the estimation is significantly reduced.

Content-Based Image Retrieval Using Multi-Resolution Multi-Direction Filtering-Based CLBP Texture Features and Color Autocorrelogram Features

  • Bu, Hee-Hyung;Kim, Nam-Chul;Yun, Byoung-Ju;Kim, Sung-Ho
    • Journal of Information Processing Systems
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    • 제16권4호
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    • pp.991-1000
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    • 2020
  • We propose a content-based image retrieval system that uses a combination of completed local binary pattern (CLBP) and color autocorrelogram. CLBP features are extracted on a multi-resolution multi-direction filtered domain of value component. Color autocorrelogram features are extracted in two dimensions of hue and saturation components. Experiment results revealed that the proposed method yields a lot of improvement when compared with the methods that use partial features employed in the proposed method. It is also superior to the conventional CLBP, the color autocorrelogram using R, G, and B components, and the multichannel decoded local binary pattern which is one of the latest methods.

한국표준질병·사인분류에 따른 한의 변증 설문지 개발 및 활용현황 고찰 (Review on the Development State and Utilization of Pattern Identification Questionnaire in Korean Medicine by U Code of Korean Classification of Disease)

  • 장은수;김윤영;이은정;유호룡;정인철
    • 동의생리병리학회지
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    • 제30권2호
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    • pp.124-130
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    • 2016
  • The aim of this study was to suggest the future direction of diagnostic and evaluative pattern identification questionnaire (PIQ) by reviewing the state of development and utilization of PIQ according to Korean classification of disease-U (KCD-U). We surveyed the database of OASIS, NDSL, KISS, DBPIA, and Pub-med to know the kinds of developed and developing PIQ of Korean medicine. We used 'Pattern Identification' and 'Questionnaire' to find suitable papers. The inclusion criteria met 47 cases. The number of PIQ before 2000yrs, between 2001 to 2005, 2006-2010, 2011-2015 were 2, 5, 18, 22cases. The number of PIQ belonged to the disease of Korean medicine, the pathological symptom of korean medicine, the Sasang constitutional pattern identification and etc according to KCD-U were 20(42.6%), 8(17%), 9(19.1%) and 10(21.3%). Twenties among forty seven PIQ were validated, and the rest of them were not validated. The distribution of the numbers of PIQ were significantly different according to KCD-U (p=0.003). The direction of Utilization of PIQ was 36 questionnaires in diagnosing PI, 14 cases in evaluating health state, 4cases in evaluating effects of a treatment and 8 ones in diagnosing Sasang constitutional types. This study reveals the status on validated and non-validated PIQ of Korean medicine and suggests the basic information for the direction of developing PIQ in the future.

한글 인식에서 자소 추출에 관한 연구 (A Study on Algorithm of Phonemes Extraction in Korean Character Pattern Recognition)

  • 정영화;김은진;김정선
    • 한국통신학회:학술대회논문집
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    • 한국통신학회 1985년도 추계학술발표회 논문집
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    • pp.109-112
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    • 1985
  • This paper proposes a algorithm of phonemes extraction in korean character pattern recognition. The phonemes are classified into the patterns which are separable and connected with each other. The former is extracted by means of pattern matching in consideration of topological structure of ponemes and direction of stroke sequentially. The latter is extracted by means of index and window algorithm which are performed by a 3$\times$3 sequential local operation in the thinned character pattern.

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ETCS용 RF 링크 설계와 안테나 빔 패턴에 의한 통신 영역 연구 (Analysis of the RF Link Design for ETCS and Study on the Communication Zone by the Antenna Beam Pattern)

  • 임춘식;하재권;안동현
    • 한국ITS학회 논문지
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    • 제3권1호
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    • pp.21-30
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    • 2004
  • 본 논문에서는 자동요금 징수 시스템(ETCS : Electronic Toll Collection System)의 RSE와 OBU 간의 RF link설계와 도로의 폭과 진행 방향 길이에서 적절한 통신 영역을 얻기 위해 요구되는 안테나의 빔 패턴 특성을 분석하였다. 이 과정은 능동형 DSRC를 기반으로 하는 ITS 서비스의 시스템 요구 규격을 결정하기 앞서 수행되어져야 하며, ETCS 기지국 설계 및 구축에서 가장 기본적이고 중요한 기술적 분석을 위하여 고찰하였다.

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초음파진동자의 복수배열에 의한 지향성가변에 관한 연구 (A Study on the Control of the Radiation Pattern of an Ultra-Sonic Beam by the Plural Arrangement of the Transducers)

  • 신형일
    • 한국항해학회지
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    • 제3권2호
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    • pp.21-30
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    • 1979
  • Echo sounder and Doppler sonar are to theultra-sonic transducers for measuring the depth and the ship's speed respectively. To measure the depth and speed with a single transducer, it is required to control the ultra-sonic beam to optional direction. In the past, the direction of the transducer itself is varied, but such a method provoked much problems in the mechanical design of the equipment. This paper deals with the method to control beam direciton by the phase control of the plural arrangement of transducers, and the results are studied by a computer simulation. The remarkable results of the study is condensed as follows; 1. The greater the interval of arrangement between transducers, the sharper the radiation pattern is, but in this case, the level of undesired sidelobe is also increased. 2. The control of radiation pattern up to 60 degree can be achieved by an adequate arrangement of more than 10 transducers. 3. It is shown that a simultaneous measurement of both depth and speed can be achieved by alternating directivity of the pulse by the method proposed in this paper.

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한복에 사용된 장식문양을 통하여 본 전통-현대화 작업에 대한 분석 -90년대 중반 이후 여성 한복을 중심으로- (A Survey on the Patterns for Traditional-Modern Work in Korean Traditional Costume -Focus on Women Dress Since in the Middle 1990s-)

  • 정혜경;박영희
    • 복식
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    • 제54권1호
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    • pp.11-21
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    • 2004
  • This study examined the kinds, shape, technique, and arrangement of pattern for the Korean traditional women costume between 1995 and 2002. The sources used this study were collected from the magazine “HANBOK, ONGOJISHIN, BEAUTIFUL OUR DRESS” Results were as follows 1) In the kinds of pattern, the most pattern of use was the flower pattern, and the geometric pattern showed the trend of increase. these results mean the use of pattern lately is progressed by the new direction. 2) In the shape of pattern, the style shapes were decreased gradually and the geometric shapes were increased. these results show that the modern beauty is chased. 3) In the technique of pattern. the results viewed that the embroidery technique used in the meantime decreased and the JOGAKBO technique increased. 4) In the arrangement of pattern, the modern arrangement was most superior in the most of year. That is estimated the arrangement of pattern have been chased the modern beauty than the others of pattern.

발생 중 마우스 망막에서 방향특이성 신경절세포의 NMDA R1 수용체의 시냅스 패턴 (Synaptic Pattern of NMDA R1 upon the Direction-Selective Retinal Ganglion Cells in Developing Mouse Retina)

  • 이지건;권오주;전창진
    • 한국안광학회지
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    • 제18권4호
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    • pp.533-540
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    • 2013
  • 목적: 본 연구에서는 발생 중[태어난 지 5일(P5), 10일(P10)] 마우스 망막의 ON-OFF 방향특이성 신경절세포 수상돌기 상에서 NMDA R1 수용체의 시냅스 패턴을 연구하고자 하였다. 방법: ON-OFF 방향특이성 신경절세포는 Lucifer yellow를 주사하여 형태학적 특징으로 동정하였다. 이극세포로부터의 글루타메이트의 흥분성 유입을 확인하기 위해 membrane traffic motor 단백질 마커인 kinesin을 이용하였다. 결과: 본 연구에서 P5, P10의 ON-OFF 방향특이성 신경절세포를 동정할 수 있었으며, NMDA R1의 면역반응반점은 내망상층에서 강하게 나타났다. ON-OFF 방향특이성 신경절세포의 수상돌기상의 수용체의 분포패턴에서 방향특이성을 예측할 수 있는 어떠한 비대칭성도 발견하지 못하였다. 결론: 이극세포로부터의 글루타메이트성 자극유입은 P5, P10 단계에서 모두 균형적으로 유입되며, 방향특이성은 NMDA R1 수용체의 특이적인 패턴에 있지 않음을 밝혔다.