• Journal of the Korea Institute of Military Science and Technology
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• v.12 no.1
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• pp.1-7
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• 2009

Tracking and detecting targets by the M/W seeker is affected by the clutter reflecting from the earth's surface. In order to detect the look-down retreating targets, which appear in the sidelobe clutter region, in the M/W seeker of High PRF mode, it is necessary to understand statistical characteristics of the surface sidelobe clutter. Statistical analysis of sidelobe clutter is conducted for several configurations of the surface using data obtained by the CFT (Captive Flight Test) of the M/W seeker in High PRF mode. The probability density function(PDF) fitting is conducted for several configuration and conditions of the surface. PDFs and PDF parameters, which best describe statistical distribution of sidelobe clutter, are estimated.

• Journal of the Korean Society for Precision Engineering
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• v.16 no.3 s.96
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• pp.180-188
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• 1999

${\mu}$-synthesis is applied to design a robust controller for a seeker scan loop system which has model uncertainty and is subject to a external disturbance due to abrupt missile maneuver. The issue of modelling a real-valued parametric uncertainty of a physical seeker scan loop system is discussed. The two-degree-of-frame control structure is employed to obtain better performance. It is shown that ${\mu}$-synthesis provides a superior framework for the robust control design of a seeker scan loop system which exhibits robust performance. The proposed robust control system satisfies design requirements, and especially shows good scanning performances for conical and rosette scan patterns despite parametric uncertainty in real system model.

• Journal of the Korean Society for Precision Engineering
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• v.12 no.1
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• pp.78-86
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• 1995

$H_{\infty}$ Controller of seeker scan-loop is designed using LSDP proposed by McFarlane. The performance and robustness of $H_{\infty}$ controller are analyzed using robustness theorems by Lehtomaki and compared with those of the LQG/LTR controller. Especially, structured singular value .mu. -test of Doyle is used to evaluate robust performance of seeker scan-loop. It is demonstated that seeker scan-loop by $H_{\infty}$ controller is very robust to model uncertainties described by additive and multiplicative perturbations.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.514-518
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• 2000

Micro wave seeker consists of a gimbal structure, a antenna and many RF parts. And Missile's propelling powers excite a gimbal structure, a antenna and many RF parts. Therefore, We must inquire into external forces to act on a micro wave seeker before everything. We must inquire into design parameters and then estimate dynamic characteristics of a gimbal structure with a finite element model to reflect part's characteristics for design for a gimbal structure in consideration of vibration features. In this paper, a gimbal structure of a micro wave seeker is modeled in finite element method and then updated by using the experimental modal data. Before we make a finite element model of a gimbal structure of a micro wave seeker, we make a finite element model of a sub-structure and compare with the experimental modal data.

• The Journal of Asian Finance, Economics and Business
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• v.2 no.3
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• pp.5-15
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• 2015

This research paper has been attempted to inventory the atmospheric factors, contributing to better sales. Exploratory study was undertaken to identify various signs of store atmospherics variables that influence the buying behaviour of buyers. Thirty-four variables identified from this study were used to create a structured questionnaire. This questionnaire was then administered among shoppers in NCR Delhi using non-probability convenience sampling. To determine the atmospheric factors, Principal Component Analysis (PCA) along with Varimax Rotation was attempted. Using principal component factor analysis on the data collected, nine factors were identified to have impact on the store atmospheric. These were Querulous, Music, Sensitive, Budget Seeker, Sensuous, Light, Idler, Space seeker and Comfort Seeker. Contrary to the various earlier studies where music, space seeker and comfort seeker were considered to be most significant factors, light and querulous have emerged out to be the major factor that influences the store atmospheric. This study shows that customers are sensitive, space seekers and sensuous. Constituents of these factors reveal distinct patterns. This research may be used as guidelines for development and management of shopping malls in emerging countries. Retail marketers in India can take this cue in designing their strategies to attract consumers.

• Proceedings of the Korean Society for Noise and Vibration Engineering Conference
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• 2000.06a
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• pp.508-513
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• 2000

Micro wave seeker detects micro wave signal reflecting from a object and modifies the angle of a antenna in the direction of a reflecting signal. Gimbal structure makes a motion in the direction of an elevation axis and an azimuth axis and change the direction of a missile toward a object. As before, Micro wave seeker is a important part of a missile. Especially, gimbal structure is designed to resist a external force generated by a strong propelling power. For that reason, it is essential to analyze a vibration feature of gimbal structure. In this paper, we analyze dynamic characteristics of a gimbal structure of a micro wave seeker. And we measure frequency response functions of a gimbal structure in order to investigate the effect of a pre-load on bearing.

• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.29 no.4
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• pp.256-265
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• 2018

We herein analyze the survivability of an airborne platform when an active decoy delivers jamming attacks against an active RF seeker system that operates based on the proportional navigation guidance law. In encounter scenarios with various conditions, such as platform maneuvering, the decoy's RF specification, and the seeker's approaching range and angles, the missed distance of the RF seeker is evaluated. By comparing the missed distance with the proximity of the fuze range, the platform's survivability is determined and the survival area of the platform is drawn on several encounter scenarios.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.48 no.11
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• pp.873-880
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• 2020

In this paper, we propose a guidance filter to estimate line of sight rate with strapdown seeker measurements and INS(Inertial Navigation System) information. The measurements of proposed guidance filter consisted of the LOS(Line of Sight) and relative position that can be calculated with the seeker's measurements, INS information and known target position, also the filter is based on an asynchronous filter to use outputs of the two sensors that are out of synchronous and period. Through the proposed filter, we can reduce the effect on parasitic loop that can be caused by using large time delay seeker and improve the estimation performance.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.43 no.1
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• pp.40-48
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• 2015

In this paper, we suggest a measurement modeling of the RF seeker using the ISAR(Inverse Synthetic Aperture Radar) image. Reference scattering points are extracted first from ISAR images which are changed according to target attitude. And then uncertainties included in RF seeker measurement such as noise strength, blink, and boresight error are added to the reference scattering points. The proposed measurement model of the RF seeker can be used to develop various kinds of target tracking algorithms.

• Journal of Agricultural Extension & Community Development
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• v.23 no.3
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• pp.321-334
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• 2016

Food is one of the essential elements of the tourist experiences. The study aims to segment food tourists for benefit sought. This study attempted to segment tourists who had experienced local food at tourist destinations by their benefit sought to meet local food. A self-administered survey was obtained from 498 visitors in the study areas. Results from the factor analysis show that the most explained variances of benefit sought were food taste (17.2%) and refresh (12.9%). Five distinct segments were identified based on the benefits; family seeker (17.6%), passive seeker (15.1%), want-it-all seeker (23.1%), raw material seeker (31.8%), gastronomic seeker (12.4%). In addition, a significant difference in the characteristics of tourists who had tasted local food at tourist destinations was observed in terms of occupation, income, education, expenditure for food, and tour distance. Implications are discussed relative to marketing strategies.