• Title, Summary, Keyword: Range Alignment

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통신방송위성 안테나 얼라인먼트 측정

  • Yoon, Yong-Sik;Park, Hong-Chul;Son, Young-Seon;Lee, Byoung-Gi
    • Aerospace Engineering and Technology
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    • v.3 no.1
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    • pp.117-125
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    • 2004
  • The three-dimensional precision measurement technology for industrial product of middle and/or large scale has been developed. Theodolite measurement system which is one of the technology is widely used in aerospace industry. This paper describes a range alignment method of parabolic antenna to RF probe in the near field range by using the theodolite system. The range alignment of the Ku-band and Ka-band antennas has been accomplished within the requirements, ±1 mm and ±$0.05^{circ}$.

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Evaluation of Optimal Horizontal Alignment Considering Ride Comfort in Renewal of Curved Tracks (곡선부 선형개량 시 승차감을 고려한 최적평면선형 평가)

  • Um, Ju-Hwan;Choi, Il-Yoon;Lee, Jun S.
    • Journal of the Korean Society for Railway
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    • v.18 no.5
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    • pp.457-465
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    • 2015
  • A method of evaluating the optimal alignment range while considering ride comfort when performing line renewal of curved tracks for speed-up is proposed in this study. The proposed method was applied to analyze the optimal renewal range for horizontal alignments with the smallest curve radii in the Kyung-Bu high-speed line; a parametric study on the effects of various initial design conditions on the permissible renewal range and optimal alignment range was also performed. From the analysis results, it was found that the permissible range is enhanced in proportion to the increase in the curve radius and the cant. It was also verified that a slight adjustment of the horizontal alignment enables speed-up even in the case of R7000/R8000, placed in the ballasted track section of the Kyung-Bu high-speed line.

Range Alignment Measurement for Satellite Antenna by Using Theodolite System (데오드라이트 시스템을 이용한 위성 안테나 레인지 얼라인먼트 측정)

  • Park, Hong-Cheol;Son, Yeong-Seon;Yun, Yong-Sik
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.32 no.6
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    • pp.134-141
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    • 2004
  • The three-dimensional precision measurement technology for industrial product of middle and/or large scale has been developed. Theodolite measurement system which is one of the technology is widely used in aerospace industry. This paper describes a range alignment method of parabolic antenna to RF probe in the near field range by using the theodolite system, The range alignments of the Ku-band and Ka-band antennas have been accomplished within the requirements, ${\pm}1mm\;and\;{\pm}0.05^{\circ}$.

Methodology of System Alignment using Angular Error Compensation Among Multi-Axes (다중 좌표계간 각도오차 보정을 통한 체계정렬 기법)

  • Ha, Jong-Soo;Lee, Eui-Hyuk;Lee, Hyun-Ah;Park, Gyu-Churl;Cho, Kyu-Gong
    • Journal of the Korea Institute of Military Science and Technology
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    • v.17 no.3
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    • pp.342-349
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    • 2014
  • MRDS is a short range missile/rocket defense system which protects a main battle tank(MBT) from threats in a short range. It is composed of 2 radars, 2 infrared trackers(IRTs), 1 fire control computer(FCC), 2 launchers and countermeasures. To guarantee the performance of the MRDS, these components have to be mounted on the vehicle with the known positions and directions and it is required to compensate the alignment errors. In this paper, a system alignment method using angular error compensation is proposed to install its components within a tolerance on the MBT. The test results are presented to evaluate and verify the effectiveness of the proposed method.

Alignment of Ag nanoparticles by an external electric field proposed for metamaterial applications

  • Gholipur, Reza;Bahari, Ali
    • Current Applied Physics
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    • v.17 no.7
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    • pp.989-998
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    • 2017
  • The ability to control the DNG properties of metamaterials in the microwave range makes possible many new constructions and practical applications. In addition, since the fabrication of ordered metamaterials with metallic structure arrays is habitually complex, the mass production of these structures is being prevented. For this purpose, a control on spatial structure of random metamaterial at the nanoscale dimensions was performed. Here, we demonstrate the alignment of dispersed Ag nanoparticles subjected to external AC electric field created by quadrupole electrode in refluxing condition at $180^{\circ}C$. External electric field allows for alignment of the well-dispersed Ag nanoparticles with long-range orientational order. The effects of the AC electric field on the DNG region that obtained in the microwave range can be accompanied with a control on optical performances, even in the plasmonic field for future studies. This achievement provides a new way toward the development of random metamaterial devices.

Vertical Alignment of Nematic Liquid Crystal on the SiC Thin Film Layer with Ion-beam Irradiation

  • Oh, Yong-Cheul;Lee, Dong-Gyu
    • Transactions on Electrical and Electronic Materials
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    • v.7 no.6
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    • pp.301-304
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    • 2006
  • We studied the nematic liquid crystal (NLC) aligning capabilities using the new alignment material of the SiC (Silicon Carbide) thin film. The SiC thin film exhibits good chemical and thermal stability. The good thermal and chemical stability make SiC an attractive candidate for electronic applications. A vertical alignment of nematic liquid crystal by atomic beam exposure on the SiC thin film surface was achieved. The about $87^{\circ}$ of stable pretilt angle was achieved at the range from $30^{\circ}\;to\;45^{\circ}$ of incident angle. Consequently, the vertical alignment effect of liquid crystal electro-optical characteristic by the atomic beam alignment method on the SiC thin film layer can be achieved.

Chemical Structural Effects of Polyimides on the Alignment and Electro-optical Properties of Liquid Crystal Cells

  • Paek, Sang-Hyon;Wonseok Dong
    • Macromolecular Research
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    • v.12 no.3
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    • pp.251-257
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    • 2004
  • The nature of the nematic liquid crystal (LC) alignment induced by the rubbed polyimide (PI) alignment layers (ALs) and the electro-optical (EO) properties of the LC cells are expected to depend on the chemical and physical features of the PI. By employing five pyromellitic dianhydride (PMDA)-type PIs having different functionalities, we have studied the effects of the PI's structure and chemistry on the alignment characteristics and the cell's EO properties. Increasing the flexibility of the PI increases the pretilt angle and tends to improve the alignment stability. On the other hand, the rigid, fluorinated PI displays poor stability for LCs and induces a less stable/uniform LC alignment and, subsequently, a small pre tilt angle. It also transpired that fluorination of the PI deteriorated the voltage-transmittance characteristics and the voltage holding ratio; increasing the flexibility of the PI structure improves these EO properties. The finding that the qualitative trends for the PI's functionalities are similar for both the alignment and EO properties suggests that the EO properties are closely related to the alignment characteristics, which are determined by short-range interactions between LC and PI molecules.

A Study of Comparison of Pelvic Alignment, Hip Joint Range of Motion About 20's Female University Students' With Dysmenorrhea (여대생의 월경곤란증 정도에 따른 골반정렬과 고관절 가동범위의 비교연구)

  • Choi, Im-soon;Jang, Hyun-jeong
    • The Journal of Korean of Orthopedic Manual Physical Therapy
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    • v.21 no.2
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    • pp.47-52
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    • 2015
  • Background: The objective of this study was to compare dysmenorrhea with pelvic alignment, hip joint range of motion about 20's female university students. Sixty two female students participated in this study. To investigate the measure of dysmenorrhea, we used modified menstrual distress questionnaire (MMDQ) and numerric rating scale (NRS). The pelvic alignment was assessed by using the palpation meter. The active range of motion (ROM) were assessed by measuring the flexion, extension, abduction, adduction, internal rotation and external rotation. Each measurement was assessed by goniometer. The data were analyzed by calculating independent T-test. Consequently, As the increase of dysmenorrhea, we observed significantly the increase of pelvic anterior tilt in right and left pelvic (p<.05). Otherwise, as the increase of dysmenorrhea, range of motion of hip joint was significantly limited in right and left external rotation (p<.05). Thus, this study provides young female with valuable information about dysmenorrhea.

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Registration of Dental Range Images from a Intraoral Scanner (Intraoral Scanner로 촬영된 치아 이미지의 정렬)

  • Ko, Min Soo;Park, Sang Chul
    • Korean Journal of Computational Design and Engineering
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    • v.21 no.3
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    • pp.296-305
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    • 2016
  • This paper proposes a framework to automatically align Dental range image captured by depth sensors like the Microsoft Kinect. Aligning dental images by intraoral scanning technology is a difficult problem for applications requiring accurate model of dental-scan datasets with efficiency in computation time. The most important thing in dental scanning system is accuracy of the dental prosthesis. Previous approaches in intraoral scanning uses a Z-buffer ICP algorithm for fast registration, but it is relatively not accurate and it may cause cumulative errors. This paper proposes additional Alignment using the rough result comes after intraoral scanning alignment. It requires that Each Depth Image of the total set shares some overlap with at least one other Depth image. This research implements the automatically additional alignment system that aligns all depth images into Completed model by computing a network of pairwise registrations. The order of the each individual transformation is derived from a global network and AABB box overlap detection methods.

The Effect of Corrective Exercise in a patient with knee joint valgus deformity: A single-subject A-B-A experimental design (외반슬 환자의 교정운동의 효과: 단일 피험자 A-B-A 실험 설계)

  • Lee, Ho-Seong;Kim, Ah-Ram
    • Journal of the Korean Society of Physical Medicine
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    • v.11 no.1
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    • pp.93-105
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    • 2016
  • PURPOSE: The purpose of this study was to determine the effect of corrective exercise on hip joint range of motion, lower limb alignment, radiographs of hip and knee joints, and quadriceps muscle activity in a patient with knee joint valgus deformity. METHODS: A single-subject A-B-A experimental design was used to determine the effects of therapeutic exercise. The single-subject was a 27-year-old male, who presented with knee joint valgus deformity. Corrective exercise program was performed for 40 min/day twice a week for 12-week. Range of motion (hip flexion, extension, abduction, adduction, internal rotation, and external rotation), lower limb alignment test (Q-angle, rear foot alignment, and leg length), standing anterior-posterior radiographs (neck shaft angle and knee joint space), and quadriceps muscle activity of both lower limbs were measured before (A 1), after 6 weeks (B 1) and after 12-weeks (B 2) of corrective exercise and after 6 weeks of exercise completion (A 2). RESULTS: Hip range of motion increased in all directions of both sides at B 2 and A 2 compared to at A 1. Q-angle of both side and leg length discrepancy decreased at B 2 and A 2 compared to at A 1. Neck shaft angle and knee joint space of both sides improve at B 2 and A 2 compared to at A 1. Quadriceps of both side muscle activities improved at B 2 and A 2 compared to at A 1. CONCLUSION: We demonstrated that corrective exercise increases range of motion, and improves lower limb alignment and muscle activity in a patient with knee joint valgus deformity.