• 제목/요약/키워드: Range

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비등방성 센서 네트워크에서 가상 홀을 이용한 다중 홉 Range-Free 측위 알고리즘 (Multihop Range-Free Localization with Virtual Hole Construction in Anisotropic Sensor Networks)

  • 이상우;김선우
    • 한국통신학회논문지
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    • 제38C권1호
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    • pp.33-42
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    • 2013
  • 본 논문에서는 비등방성 센서 네트워크에서 노드 간 연결 정보만을 이용하여 일반노드의 위치를 찾는 다중 홉 Range-free 측위 알고리즘을 제안한다. 제안하는 측위 알고리즘에서 일반노드는 자신과 앵커노드 쌍이 이루는 최단경로의 측정 홉 수와 기대 홉 수를 비교하여 최단경로의 우회 정도를 측정하고, 우회 정도에 따라 자신으로부터 앵커노드까지의 거리를 추정한다. 일반노드는 이러한 과정을 네트워크의 모든 앵커노드 쌍에 대하여 반복하며, 획득한 거리 정보를 사용하여 위치를 추정한다. 제안하는 알고리즘은 기존의 Range-free 알고리즘에 비해 적은 수의 앵커노드를 필요로 하며, 적은 통신 오버헤드를 갖는다. 마지막으로 성능평가를 위하여 MATLAB 시뮬레이션을 수행하였으며, 기존의 Range-free 측위 알고리즘에 비해 향상된 위치정확도를 보였다.

Estimation of Ionospheric Delays in Dual Frequency Positioning - Future Possibility of Using Pseudo Range Measurements -

  • Isshiki, Hiroshi
    • 한국항해항만학회:학술대회논문집
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    • 한국항해항만학회 2006년도 International Symposium on GPS/GNSS Vol.2
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    • pp.185-190
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    • 2006
  • The correct estimation of the ionospheric delays is very important for the precise kinematic positioning especially in case of the long baseline. In case of triple frequency system, the ionospheric delays can be estimated from the measurements, but, in case of dual frequency system, the situation is not so simple. The precision of those supplied by the external information source such as IONEX is not sufficient. The high frequency component is neglected, and the precision of the low frequency component is not sufficient for the long baseline positioning. On the other hand, the high frequency component can be estimated from the phase range measurements. If the low frequency components are estimated by using the external information source or pseudo range measurements, a more reasonable estimation of the ionospheric delays may be possible. It has already been discussed by the author that the estimation of the low frequency components by using the external information source is not sufficient but fairly effective. The estimation using the pseudo range measurements is discussed in the present paper. The accuracy is not sufficient at present because of the errors in the pseudo range measurements. It is clarified that the bias errors in the pseudo range measurements are responsible for the poor accuracy of the ionospheric delays. However, if the accuracy of the pseudo range measurements is improved in future, the method would become very promising.

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A Survey on Improvements of Range Hood in Apartment

  • Kang, Kyungmo;Kim, Taeyeon;Lee, Yun-gyu
    • KIEAE Journal
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    • 제17권5호
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    • pp.43-50
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    • 2017
  • Purpose: Residential cooking(gas or electricity) emits many air pollutants. For Removal of these contaminants, range hood is play an important role in the cooking activities. However, deterioration about performance of range hood can be occur in used range hood which is not verified on performance by testing balancing and adjusting in apartment. So, purpose of this study is to improve the range hood against cooking-generated contaminations. Method: To improve hood, survey of range hood which mounted in apartment have to conduct at first. In this study, the survey was conducted for 3 steps. First, Visual inspection for conditions of range hood. Second, questionnaire of operating and maintenance method. Third, interview with user about need for improvement, complainant. Finally, we integrated the survey for range hood and introduced the probable cause of deterioration through this comprehensive survey. Result: Result of measurement for air volume for range hood, A measured air volume has reduced by 41.4, 38.0, 32.0% each step from rated air volume. There are lots of reasons of this phenomenon including to maintenance, air path of duct, lower-cost devices, exhaust ports. For solve this problem, guideline about operating hood, user in apartment will have to supply with maintenance information at first.

정상 성인의 견, 고관절 가동범위에 대한 조사 (Shoulder and Hip Joint Range of Motion in Normal Adults)

  • 함용운
    • The Journal of Korean Physical Therapy
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    • 제3권1호
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    • pp.97-108
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    • 1991
  • The purpose of this article is to know the standard figures of joint range of motion, in conjuction with age and sen, for normal adults. The results of assessment and analysis io shoulder and hip joint range of motion are as follows : 1) The average shoulder joint range of motion in normal adults are $160.5^{\circ}$ in flexion, $53.5^{\circ}$ in extension, $159.3^{\circ}$ in adduction, $62.3^{\circ}$ in internal rotation, $83.9^{\circ}$ in external rotation, The average hip joint range of motions are $116.8^{\circ}$ in flexion, $16.1^{\circ}$ in extension, $41.1^{\circ}$ in abduction, $33.8^{\circ}$ in abduction, $40.0^{\circ}$ in interne rotation, $41.2^{\circ}$ in external rotation. 2) There is no significant difference in shoulder and hip joint range of motion between male and female (p>0.05). 3) As to the inter-relation in age and range of motion, the left flexion and extension, internal rotation and right extension in shoulder joint is decreased gradually with increasing age, and left flexion (knee flexion, knee extension) and right flexion (knee extension) in hip joint is decreased with increasing age (p<0.01). 4) Relating to age and sex, the twenties male shows highest range of motion in shoulder and hip joint, with .the fifties female shows, lowest range of motion.

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Upgrade of gamma electron vertex imaging system for high-performance range verification in pencil beam scanning proton therapy

  • Kim, Sung Hun;Jeong, Jong Hwi;Ku, Youngmo;Jung, Jaerin;Cho, Sungkoo;Jo, Kwanghyun;Kim, Chan Hyeong
    • Nuclear Engineering and Technology
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    • 제54권3호
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    • pp.1016-1023
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    • 2022
  • In proton therapy, a highly conformal proton dose can be delivered to the tumor by means of the steep distal dose penumbra at the end of the beam range. The proton beam range, however, is highly sensitive to range uncertainty, which makes accurately locating the proton range in the patient difficult. In-vivo range verification is a method to manage range uncertainty, one of the promising techniques being prompt gamma imaging (PGI). In earlier studies, we proposed gamma electron vertex imaging (GEVI), and constructed a proof-of-principle system. The system successfully demonstrated the GEVI imaging principle for therapeutic proton pencil beams without scanning, but showed some limitations under clinical conditions, particularly for pencil beam scanning proton therapy. In the present study, we upgraded the GEVI system in several aspects and tested the performance improvements such as for range-shift verification in the context of line scanning proton treatment. Specifically, the system showed better performance in obtaining accurate prompt gamma (PG) distributions in the clinical environment. Furthermore, high shift-detection sensitivity and accuracy were shown under various range-shift conditions using line scanning proton beams.

복수의 거리영상 간의 변환계수의 추출 (Registration multiple range views)

  • 정도현;윤일동;이상욱
    • 전자공학회논문지S
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    • 제34S권2호
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    • pp.52-62
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    • 1997
  • To reconstruct the complete 3-D shape of an object, seveal range images form different viewpoints should be merged into a single model. The process of extraction of the transformation parameters between multiple range views is calle dregistration. In this paper, we propose a new algorithm to find the transformation parameters between multiple range views. Th eproposed algorithm consists of two step: initial estimation and iteratively update the transformation. To guess the initial transformation, we modify the principal axes by considering the projection effect, due to the difference fo viewpoints. Then, the following process is iterated: in order to extract the exact transformation parameters between the range views: For every point of the common region, find the nearest point among the neighborhood of the current corresponding point whose correspondency is defined by the reverse calibration of the range finder. Then, update the transformation to satisfy the new correspondencies. In order to evaluate the performance the proposed registration algorithm, some experiments are performed on real range data, acquired by space encoding range finder. The experimental results show that the proposed initial estimation accelerate the following iterative registration step.

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셔츠와 넥타이의 배색방법에 따른 조화 영역과 부조화 영역 (The Harmony Range and the Disharmony Range According to Types of Coloration in Men's Shirts and Neckties)

  • 임지영
    • 복식
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    • 제57권5호
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    • pp.183-195
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    • 2007
  • The purpose of the study was to investigate the harmony range and the disharmony range by evaluating the degrees of harmony in terms of types of coloration in men's shirts and neckties. In addition, the study aimed to examine perceptional differences between male and female towards degrees of harmony affected by types of coloration; tone on tone coloration(64), tone in tone coloration(96), contrast coloration(128), achromatic-chromatic coloration(96), and achromatic-achromatic coloration(16). The 4,032 male and 4,032 female college students, were participated in this study. The results are as follows. For five types of coloration, the harmony range and disharmony range were identified. Tone on tone and achromatic-chromatic coloration had a more wide range than tone in tone and contrast coloration from both male and female students. The male students had a more wide range of harmony on all coloration.

능동 소나 체계에서의 표적 탐지거리 예측 알고리즘과 최적 탐지깊이 결정에의 응용 (Detection Range Estimation Algorithm for Active SONAR System and Application to the Determination of Optimal Search Depth)

  • 박재은;김재수
    • 한국해양공학회지
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    • 제8권1호
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    • pp.62-70
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    • 1994
  • In order to estimate the detection range of a active SONAR system, the SONAR equation is commonly used. In this paper, an algorithm to calculate detection range in active SONAR system as function of SONAR depth and target depth is presented. For given SONAR parameters and environment, the transmission loss and background level are found, signal excess is computed. Using log-normal distribution, signal excess is converted to detection probability at each range. Then, the detection range is obtained by integrating the detection probability as function of range for each depth. The proposed algorithm have been applied to the case of omni-directional source with center frequency 30Hz for summer and winter sound profiles. It is found that the optimal search depth is the source depth since the detection range increase at source depth where the signal excess is maximized.

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Compact and versatile range-finding speedometer with wide dynamic range

  • Shinohara, Shigenobu;Pan, Derong;Kosaka, Nozomu;Ikeda, Hiroaki;Yoshida, Hirofumi;Sumi, Masao
    • 제어로봇시스템학회:학술대회논문집
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    • 제어로봇시스템학회 1995년도 Proceedings of the Korea Automation Control Conference, 10th (KACC); Seoul, Korea; 23-25 Oct. 1995
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    • pp.158-161
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    • 1995
  • A new laser diode range-finding speedometer is proposed, which is modulated by a pair of positive and negative triangular pulse current superimposed on a dc current. Since a target velocity is directly obtained form a pure Doppler beat frequency measured during the non-modulation period, the new sensor is free from the difficulties due to the critical velocity encountered in the previous sensor. Furthermore, the different amplitude of the two triangular pluses are so adjusted that the measurable range using only one laser head is greatly expanded to 10cm through 150cm, which is about two times that of the previous sensor. The measurement accuracy for velocity of .+-.6mm/s through .+-.20mm/s and for range is about 1%, and 2%, respectively. Because the new sensor can be operated automatically using a microcomputer, it will be useful for application of a 3-D range image measurement of a slowly moving object.

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모음 주파수 범위에 따른 성문전도 스펙트럼 기울기 (Electroglottographic Spectral Tilt in Frequency Ranges of Vowel Sound)

  • 김지혜;장애란;정동근
    • 센서학회지
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    • 제24권4호
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    • pp.247-251
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    • 2015
  • In this study, electroglottographic spectral tilt (EST) was investigated for characterization of vocal cords vibration. EST was analyzed from the power spectrum of electroglottographic signals by dividing frequency analysis range as full range (0~4 octave), low range (0~2 octave), and high range (2~4 octave). EST of all ranges in female were greater than those in male. In female and male groups, EST of high range was higher than that of low range. This result suggests that EST has at least two components and dividing frequency range in analysis of EST is effective for investigating characteristics of vocal cords vibration.