• Title/Summary/Keyword: Range

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Range Walk Compensated Squint Cross-Range Doppler Processing in Bistatic Radar (바이스태틱 레이더에서 Range Walk이 보상된 Squint Cross-Range 도플러 프로세싱)

  • Youn, Jae-Hyuk;Kim, Kwan-Soo;Yang, Hoon-Gee;Chung, Yong-Seek;Lee, Won-Woo;Bae, Kyung-Bin
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.22 no.11
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    • pp.1141-1144
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    • 2011
  • Range walk has been a major problem in achieving correct Doppler processing. This frequently occurs when range variation is severe just like in a bistatic radar or in high speed target scenario. This paper presents a range walk compensated range-Doppler processing algorithm applicable to the bistatic radar. In order for the compensation, a range-domain interpolation is applied for range compressed signal so that Doppler processing is performed along the evenly time-spaced range bins that contain target returns. Under a bistatic radar scenario, the proposed algorithm including a range domain pulse compression is mathematically described. Finally, the validity of the algorithm is demonstrated by simulation results showing the superiority of a SCDP(Squint Cross-range Doppler Processing) over an uncompensated Doppler processing.

Robust range-only beacon mapping in multipath environments

  • Park, Byungjae;Lee, Sejin
    • ETRI Journal
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    • v.42 no.1
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    • pp.108-117
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    • 2020
  • This study proposes a robust range-only beacon mapping method for registering the locations of range-only beacons automatically. The proposed method deals with the multipath propagation of signals from range-only beacons using the range-only measurement association (RoMA) and an unscented Kalman filter (UKF). The RoMA initially predicts the candidate positions of a range-only beacon. The location of the range-only beacon is then updated using the UKF. With the proposed method, the locations of range-only beacons are accurately estimated in a multipath environment. The proposed method also provides the location uncertainty of each range-only beacon. Simulation results using the model for multipath propagation and experimental results in a real indoor environment verify the performance of the proposed method.

Invariant Range Image Multi-Pose Face Recognition Using Fuzzy c-Means

  • Phokharatkul, Pisit;Pansang, Seri
    • 제어로봇시스템학회:학술대회논문집
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    • 2005.06a
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    • pp.1244-1248
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    • 2005
  • In this paper, we propose fuzzy c-means (FCM) to solve recognition errors in invariant range image, multi-pose face recognition. Scale, center and pose error problems were solved using geometric transformation. Range image face data was digitized into range image data by using the laser range finder that does not depend on the ambient light source. Then, the digitized range image face data is used as a model to generate multi-pose data. Each pose data size was reduced by linear reduction into the database. The reduced range image face data was transformed to the gradient face model for facial feature image extraction and also for matching using the fuzzy membership adjusted by fuzzy c-means. The proposed method was tested using facial range images from 40 people with normal facial expressions. The output of the detection and recognition system has to be accurate to about 93 percent. Simultaneously, the system must be robust enough to overcome typical image-acquisition problems such as noise, vertical rotated face and range resolution.

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Profile Management System of Material Piles by Dynamic Range Finding (동적 Range 검출에 의한 원료 Pile 형상 관리 시스템)

  • 안현식
    • Proceedings of the Korea Institute of Convergence Signal Processing
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    • 2000.08a
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    • pp.333-336
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    • 2000
  • In this paper, a profile management system consisting of global and local range finders is presented for the automat ion of material pile handling. A global range finder detects range data of the front part of the piles of material and a profile map is obtained from a 3D profile detection algorithm. A local range finder attached on the side of the arm of the reclaimer detects range data with the handling function dynamically, and a local profile patch is acquired from the range data A yard profile map manager constructs a map by using the 3D profile of the global range finder and revises the map by replacing it with the local profile patch obtained Iron the local range finder. The developed vision system was applied to a simulator and the results of test show that it is appropriate to use for automating the material handling.

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Range Sensitivity Analysis of a Canard Controlled Missile (유도 미사일의 사거리 민감도 연구)

  • Yang, Young-Rok;Cho, Tae-Hwan;Myong, Rho-Shin
    • Journal of the Korea Institute of Military Science and Technology
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    • v.14 no.1
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    • pp.39-48
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    • 2011
  • This study describes a range sensitivity of a canard controlled missile. An investigation was conducted into the relative importance of aerodynamic parameters on a guided missile. Also this study was analyzed by quantifying their effects on the missile range. To analyze the range sensitivity of a guided missile, a trajectory analysis program of a guided missile was developed. The range sensitivity analysis was conducted on a thrust, weight, drag and lift. The result of the range sensitivity analysis shows that the design parameters with the greatest effect on the missile range are thrust, drag, weight, and lift, in descending order of importance. The thrust on range extension is quite obvious to extend a range of a guided missile. In particular, the drag exhibited greater range sensitivity than lift at a guided flight. The result also shows that missile range could be maximized by applying the appropriate launch angle and canard pitch-up control.

Analysis of Acoustic Characteristics and Shooting Noise Prediction for Shooting Range Soundproofing in Military (군부대 방음사격장의 음향특성 분석 및 사격소음 예측)

  • Jeong, A-Yeong;Kim, Jae-Soo
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.24 no.11
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    • pp.833-839
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    • 2014
  • The shooting noise caused by shooting training, which has strength and impacts, is becoming a serious damage to the residents around the shooting range and, consequently, the number of civil appeals against the shooting noise is on the constant increase. For this reason, the military examines the effects of the shooting noise at the stage of design in constructing a shooting range and tries to build a soundproof shooting range to minimize civil appeals. However, the lack of research and data concerning propagation and attenuation, both of which characterize the shooting noise from within a soundproof shooting range, even makes it so difficult to design a soundproof shooting range in constructing it. So this study used an acoustic simulation in a soundproof shooting range to identify acoustic and propagation characteristics within the shooting range and, on this basis, predicted the noise level at an exit of the soundproof shooting range. As a result, if the form and specifications of a soundproof shooting range were decided on at the stage of design, it was possible to use a simulation to design a soundproof shooting range with optimized acoustic performance and, on this basis, to predict a sound pressure level at an exit of the soundproof shooting range. On the basis of these data, it is probably possible to determine the degree of the effects of the shooting noise on the villages around a shooting range and the extent of damage to it and to minimize civil appeals against the shooting noise and resolve the issues of compensation and agreement with ease. This study is expected to provide useful data for designing and constructing a similar soundproof shooting range.

SOME RESULTS ON THE UNIQUE RANGE SETS

  • Chakraborty, Bikash;Kamila, Jayanta;Pal, Amit Kumar;Saha, Sudip
    • Journal of the Korean Mathematical Society
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    • v.58 no.3
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    • pp.741-760
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    • 2021
  • In this paper, we exhibit the equivalence between different notions of unique range sets, namely, unique range sets, weighted unique range sets and weak-weighted unique range sets under certain conditions. Also, we present some uniqueness theorems which show how two meromorphic functions are uniquely determined by their two finite shared sets. Moreover, in the last section, we make some observations that help us to construct other new classes of unique range sets.

Free Range Hens Use the Range More When the Outdoor Environment Is Enriched

  • Nagle, T.A.D.;Glatz, P.C.
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.4
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    • pp.584-591
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    • 2012
  • To evaluate the role of using forage, shade and shelterbelts in attracting birds into the range, three trials were undertaken with free range layers both on a research facility and on commercial farms. Each of the trials on the free range research facility in South Australia used a total of 120 laying hens (Hyline Brown). Birds were housed in an eco-shelter which had 6 internal pens of equal size with a free range area adjoining the shelter. The on-farm trials were undertaken on commercial free range layer farms in the Darling Downs in Southeast Queensland with bird numbers on farms ranging from 2,000-6,800 hens. The first research trial examined the role of shaded areas in the range; the second trial examined the role of forage and the third trial examined the influence of shelterbelts in the range. These treatments were compared to a free range area with no enrichment. Aggressive feather pecking was only observed on a few occasions in all of the trials due to the low bird numbers housed. Enriching the free range environment attracted more birds into the range. Shaded areas were used by 18% of the hens with a tendency (p = 0.07) for more hens to be in the paddock. When forage was provided in paddocks more control birds (55%) were observed in the range in morning than in the afternoon (30%) while for the forage treatments 45% of the birds were in the range both during the morning and afternoon. When shelterbelts were provided there was a significantly (p<0.05) higher % of birds in the range (43% vs. 24%) and greater numbers of birds were observed in areas further away from the poultry house. The results from the on-farm trials mirrored the research trials. Overall 3 times more hens used the shaded areas than the non shaded areas, with slightly more using the shade in the morning than in the afternoon. As the environmental temperature increased the number of birds using the outdoor shade also increased. Overall 17 times more hens used the shelterbelt areas than the control areas, with slightly more using the shelterbelts in the afternoon than in the morning. Approximately 17 times more birds used the forage areas compared to the control area in the corresponding range. There were 8 times more birds using a hay bale enriched area compared to the area with no hay bales. The use of forage sources (including hay bales) were the most successful method on-farm to attract birds into the range followed by shelterbelts and artificial shade. Free range egg farmers are encouraged to provide pasture, shaded areas and shelterbelts to attract birds into the free range.

Free-range Poultry Production - A Review

  • Miao, Z.H.;Glatz, P.C.;Ru, Y.J.
    • Asian-Australasian Journal of Animal Sciences
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    • v.18 no.1
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    • pp.113-132
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    • 2005
  • With the demand for free-range products increasing and the pressure on the intensive poultry industry to improve poultry welfare especially in western countries, the number of free-range poultry farms has increased significantly. The USA, Australia and European countries have developed Codes of Practice for free-range poultry farming which detail the minimum standards of husbandry and welfare for birds. However, the performance and liveability of free-range birds needs to be improved and more knowledge is required on bird husbandry, feed supply, disease control and heat wave management. This review examines the husbandry, welfare, nutrition and disease issues associated with free-range poultry systems and discusses the potential of incorporating free-range poultry into a crop-pasture rotation system.

Segmentation and Classification of Range Data Using Phase Information of Gabor Fiter (Gabor 필터의 위상 정보를 이용한 거리 영상의 분할 및 분류)

  • 현기호;이광호;황병곤;조석제;하영호
    • Journal of the Korean Institute of Telematics and Electronics
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    • v.27 no.8
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    • pp.1275-1283
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    • 1990
  • Perception of surfaces from range images plays a key role in 3-D object recognition. Recognition of 3-D objects from range images is performed by matching the perceived surface descriptions with stored object models. The first step of the 3-d object recognition from range images is image segmentation. In this paper, an approach for segmenting 3-D range images into symbolic surface descriptions using spatial Gabor filter is proposed. Since the phase of data has a lot of important information, the phase information with magnitude information can effectively segment the range imagery into regions satisfying a common homogeneity criterion. The phase and magnitude of Gabor filter can represent a unique featur vector at a point of range data. As a result, range images are trnasformed into feature vectors in 3-parameter representation. The methods not only to extract meaningful features but also to classify a patch information from range images is presented.

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