• The Transactions of The Korean Institute of Electrical Engineers
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• v.68 no.1
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• pp.145-152
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• 2019

A composite guidance scheme is proposed for air-to-ground anti-tank missiles launched from an airborne platform. Long-range anti-tank missiles usually use a fiber optic line (FOL) for the datalink between an operator and the missile to obtain real-time target information and to command the missile. Also, impact angle control is used to maximize the warhead effectiveness, but it should be carefully implemented due to interference between the launch platform and the FOL. Thus, the proposed guidance scheme takes into account both impact angle and FOL constraints. Under system lag and acceleration limits, a selection method of guidance gains and calculation logic of the maximum achievable impact angle are proposed for a guideline of practical implementation. The performance of the proposed guidance scheme is investigated by nonlinear simulations with various engagement conditions.

• 제어로봇시스템학회:학술대회논문집
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• 1993.10b
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• pp.468-473
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• 1993

Augmented proportional navigation requires the information of a target acceleration, which must be estimated by a filtering logic. The process necessary accompanies a time lag, which degrades the guidance performance. A trade-off study between augmented and conventional proportional navigation is conducted with the time lag taken into consideration. The result shows that the conventional proportional navigation has better performance against a target maneuver in the missile-target coplane, while the augmented has better performance against out-of-coplane maneuver.

• 제어로봇시스템학회:학술대회논문집
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• 1990.10a
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• pp.469-474
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• 1990

The implementation of modern guidance law derived from optimal control theory requires accurate current states of target, for example, position, velocity and acceleration etc. But there is no sensors that measure the target states directly. So they are estimated from measurable data. For atmospheric missile engagement, direct application of the modern guidance laws may result In deterioration of Intercept performance because of poor observability associated with angles only-measurements by passive seeker and homing geometry. In this paper, a trajectory modulation method called "adaptive Intermittent maneuvers" is added to the modern guidance law, so the observability is enhanced and, consequently, improved the intercept performance. The estimation algorithm called "modified gain pseudo-measurement filter" is used for tracking filter. It is assumed that the passive seeker measure the angles between line of sight and Inertial frame. The Monte-Carlo simulation for realistic air-to-air Intercept scenario are conducted to demonstrate the effectiveness of intermittent maneuvers.ermittent maneuvers.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.41 no.4
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• pp.314-318
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• 2013

Tests and evaluations following the U.S. MIL-HDBK/STANDARD were successfully conducted to assure the performance of the air-to-surface guidance kit which was developed first in Korea. Various ground tests confirmed the operation capability and reliability of the guidance kit, and flight tests proved very good mid-range gliding performance and accuracy of the gliding bomb which was a general purpose bomb with the guidance kit.

• Journal of Fisheries and Marine Sciences Education
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• v.22 no.1
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• pp.79-90
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• 2010

This study referred to relevant literatures, collected professional advice, created the sphere of duty with considering the characteristics of marine products-marine transportation education and teachers' specialty, and researched the feasibility of duty sphere classified from 2nd of September in 2008 to 20th of October in 2008 by selecting 80 professional teachers at random teachers who were working in 4 schools that had local 1. As the result of this study, it is proper to classify the sphere of marine products-marine transportation professional teachers into teaching-learning sphere, actual training guidance sphere, life guidance sphere, class management sphere, administrative performance sphere, specialty extension sphere, academic-industrial cooperation and community connection sphere. 2. For the contents of each sphere of marine products-marine transportation teachers' duty, it is proper to systematize teaching-learning field with 32 contents of duty, actual training guidance field with 21 contents of duty, life guidance sphere with 18 contents of duty, class management sphere with 12 contents of duty, administrative performance sphere with 18 contents of duty, specialty extension sphere with 15 contents of duty, academic-industrial cooperation and community connection sphere with 9 contents of duty respectively.

• Korean Journal of Human Ecology
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• v.9 no.4
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• pp.55-66
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• 2006

The purpose of this study was to identify the effect on the evaluation or a female teachers' role-performance based on appearance according to backgrounds of students and their parents. For this study, data was collected between October 19 and 29, 2005 by means of a questionnaire designed to gauge a subject's evaluation of a teacher's abilities in learning guidance, living guidance, and human relations. The researchers selected two middle schools and four high schools in the city of Gwang-ju. The 398 surveys completed were analyzed using factor analysis, one-way ANOVA, Duncan's multiple range test, t-test and descriptive statistics. According to the study, the evaluation of a female teacher's abilities varies with the backgrounds of both students and their parents. Among the students tested perceptions were affected by gender, grade level and type of school attended. For mothers there were differences based on age, occupation and family income.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.8
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• pp.574-581
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• 2019

This paper investigates the effects of thrust misalignments and offsets of the lateral center of gravity of a space launch vehicle on its guidance performance. Sensitivity analysis and Monte Carlo simulations are applied to analyze their effects by computing changes in orbit injection errors when including the error sources. To compensate their effects, the attitude controller including an integrator additionally and the Steering Misalignment Correction (SMC) routine of the Saturn V are considered, and then Monte Carlo simulations are performed to evaluate their performances.

• Journal of Advanced Navigation Technology
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• v.2 no.2
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• pp.84-99
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• 1998

As a part of closed-loop guidance law studies for anti-ballistic missile defense, a mid-course guidance law is proposed to engage the target with the predetermined attitude for increased terminal effectiveness. The proposed guidance law is based on the predicted target position calculated from a simplified solution of target motion and the estimates of an extended Kalman filter utilizing noisy nonlinear radar measurements. Extension of the proposed mid-course guidance to 3 dimensional engagements are also studied. Performance of the proposed mid-course guidance law together with a terminal guidance law in the form of conventional proportional navigation guidance is evaluated by a series of simulation studies.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.47 no.6
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• pp.429-437
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• 2019

This paper deals with a ZEM (Zero-Effort-Miss) based guidance law for the interception of moving targets and characteristics of the guidance law according to time-to-go estimation methods. To derive the ZEM vector feedback guidance command, we introduce a polynomial function with unknown coefficient, and then we determine the coefficient to satisfy initial and terminal constraints. Since the directions of the guidance command and ZEM vectors are adjusted by the time-to-go, general time-to-go estimation methods are proposed, which can generate the vertical and horizontal guidance commands with respect to an arbitrary reference frame. By performing various numerical simulations, the performance and characteristics of the proposed methods are investigated.

• Journal of Institute of Control, Robotics and Systems
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• v.20 no.12
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• pp.1217-1224
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• 2014

This paper presents a modified track guidance algorithm for formation flight of multiple UAVs. The suggested guidance algorithm is the spatial version of the first order dynamic characteristics for a time-dependent system so the algorithm is able to generate a path without overshoot to track the desired line. A crucial design parameter is a spatial constant that controls the shape of the convergence to an assigned flight path similarly to a time constant. Reference flight trajectories are designed based on a two-dimensional vehicle model, and the performance of the proposed guidance law is verified by numerical simulation using rigid body UAV dynamics with MATLAB/Simulink Aerosim Blockset.