• 한국항공운항학회지
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• 제18권1호
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• pp.19-26
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• 2010

To expand the application area of global navigation satellite systems, precision landing is one of the most critical area to be solved. For the development and validation of the precision landing system, many aspects need to be analyzed including the system architecture, signal characteristics, atmospheric delay, communication delay, accuracy, integrity, and availability. Among them, the signal characteristics analysis requires the processing of measurements collected by real-flight experiments. This paper presents the processing results of the real measurements collected by a flight and landing experiment. To process and analyze the data, double differencing position-domain hatch filter is utilized. Accuracy of the proposed filter is evaluated utilizing reference trajectory generated by commercial software. Finally, by comparing with conventional range domain characteristics of position domain filter is analyzed.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2006년도 춘계학술대회 논문집
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• pp.141-142
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• 2006

This paper describes estimation method for 2D position error of planar XY stage from measured profiles of guide-ways. The XY stage usually moves along its guide ways. The motion error of each stage has effect on 2D position errors of XY stages and affected mainly by profiles of guide-ways. To estimate 2D position error and flatness of stages, the profiles of guide-ways were measured and used in motion error estimation.

• 한국컴퓨터정보학회논문지
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• 제23권2호
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• pp.35-43
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• 2018

In this paper, we propose a grid-based efficient routing protocol for a mobile sink in wireless sensor networks. In the proposed protocol, the network is partitioned into grids and each grid has a grid head. For the efficient routing to a mobile sink, the proposed protocol uses a mobile sink representative node to send the data to a mobile sink and grid heads are used as a mobile sink representative node. Furthermore, the proposed protocol uses nodes in the boundary of the center grid as position storage nodes. The position storage nodes store the position of a mobile sink representative node and provide source nodes with it for data delivery. With these features, the proposed protocol can reduce a lot of overhead to update the position information and improve the delay of data delivery to a mobile sink. The proposed protocol performs better than other protocols in terms of the delay and the energy consumption per node in the performance evaluation.

• 한국멀티미디어학회논문지
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• 제25권5호
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• pp.739-747
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• 2022

In this study, the effect of augmented reality subtitle content on users was investigated by using a subjective evaluation method and a statistical approach. The human factor was defined as subtitle position and font size. Then, we analyzed the effects of the defined factors on human eye comfort and visibility. Ten participants conducted related survey evaluation tasks with a 1-minute break after viewing the content for 3 minutes.

• 한국결정학회:학술대회논문집
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• 한국결정학회 2002년도 정기총회 및 추계학술연구발표회
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• pp.5-6
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• 2002

The new spectrometer for X-ray Induced Electron Emission Spectroscopy (XIEES) .has been recently developed in KRISS in collaboration with PTI (Russia). The spectrometer allows to perform research using the XAFS, SXAFS, XANES techniques (D.C.Koningsberger and R.Prins, 1988) as well as the number of techniques from XIEES field(L.A.Bakaleinikov et all, 1992). The experiments may be carried out with registration of transmitted through the sample x-rays (to investigate bulk samples) or/and total electron yield (TEY) from the sample surface that gives the high (down to several atomic mono-layers in soft x-ray region) near surface sensitivity. The combination of these methods together give the possibility to obtain a quantitative information on elemental composition, chemical state, atomic structure for powder samples and solids, including non-crystalline materials (the long range order is not required). The optical design of spectrometer is made according to Johannesson true focusing schematics and presented on the Fig.1. Five stepping motors are used to maintain the focusing condition during the photon energy scan (crystal angle, crystal position along rail, sample goniometer rail angle, sample goniometer position along rail and sample goniometer angle relatively of rail). All movements can be done independently and simultaneously that speeds up the setting of photon energy and allows the using of crystals with different Rowland radil. At present six curved crystals with different d-values and one flat synthetic multilayer are installed on revolver-type monochromator. This arrangement allows the wide range of x-rays from 100 eV up to 25 keV to be obtained. Another 4 stepping motors set exit slit width, sample angle, channeltron position and x-ray detector position. The differential pumping allows to unite vacuum chambers of spectrometer and x-ray generator avoiding the absorption of soft x-rays on Be foil of a window and in atmosphere. Another feature of vacuum system is separation of walls of vacuum chamber (which are deformed by the atmospheric pressure) from optical elements of spectrometer. This warrantees that the optical elements are precisely positioned. The detecting system of the spectrometer consists of two proportional counters, one scintillating detector and one channeltron detector. First proportional counter can be used as I/sub 0/-detector in transmission mode or by measuring the fluorescence from exit slit edge. The last installation can be used to measure the reference data (that is necessary in XANES measurements), in this case the reference sample is installed on slit knife edge. The second proportional counter measures the intensity of x-rays transmitted through the sample. The scintillating detector is used in the same way but on the air for the hard x-rays and for alignment purposes. Total electron yield from the sample is measured by channeltron. The spectrometer is fully controlled by special software that gives the high flexibility and reliability in carrying out of the experiments. Fig.2 and fig.3 present the typical XAFS spectra measured with spectrometer.

• 치과방사선
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• 제13권1호
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• pp.7-15
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• 1983

The purpose of this study was to investigate the radiographic images of the condylar head in clinically normal subjects and the TMJ patients using standardized projection technique. 45 subjects who have not clinical evidence of TMJ problems and 96 patients who have the clinical evidence of TMJ problems were evaluated, but the patients who had fracture, trauma and tumor on TMJ area were discluded in this study. For the evaluation of radiographic images, the author has observed the condylar head positions in closed mouth and 2.54㎝ open mouth position taken by the standardized transcranial oblique lateral projection technique. The results were as follows: 1. In closed mouth position, the crest of condylar head took relatively posterior position to the deepest point of the glenoid fossa in 8.9 % of the normals and in 26.6% of TMJ patients. 2. In 2.54㎝ open mouth position, condylar head took relatively posterior position to the articular eminence in 2.2% of TMJ patients and 39.6% of the normals. 3. In open mouth position, the horizontal distance from the deepest point of the glenoid fossa to the condyla head was 13.96㎜ in the normals and 10.68㎜ in TMJ patients. 4. The distance of true movement of condyalr head was 13.49㎜ in the normals and l0.27㎜ in TMJ patients. 5. The deviation of mandible in TMJ patients was slightly greater than that of the normals.

• Journal of Power Electronics
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• 제11권4호
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• pp.464-470
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• 2011

In this paper, the feasibility of applying a position sensorless control technique to hybrid electric vehicles (HEVs) is practically evaluated. The proposed position estimator has a straightforward structure with properties that combines the model and the saliency tracking-based rotor position estimation for interior permanent magnet synchronous motors (IPMSMs). The proposed method can be used in the event of sensor loss or sensor recovery to sustain continuity of operations. The developed system takes into account the estimated position transition between two distinct sensorless methods. The transition is enhanced by introducing a synchronized transition algorithm based on a single tracking observer. Extensive experimental results are presented to verify the principles and show a reliable estimation performance over the entire speed range including standstill under 150% load conditions.

• Nuclear Engineering and Technology
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• 제53권10호
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• pp.3431-3437
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• 2021

In this study, one-dimensional gamma ray source positions are estimated using a plastic scintillating optical fiber, two photon counters and via data processing with a machine learning algorithm. A nonlinear regression algorithm is used to construct a machine learning model for the position estimation of radioactive sources. The position estimation results of radioactive sources using machine learning are compared with the theoretical position estimation results based on the same measured data. Various tests at the source positions are conducted to determine the improvement in the accuracy of source position estimation. In addition, an evaluation is performed to compare the change in accuracy when varying the number of training datasets. The proposed one-dimensional gamma ray source position estimation system with plastic scintillating fiber using machine learning algorithm can be used as radioactive leakage scanners at disposal sites.

• 디지털산업정보학회논문지
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• 제14권4호
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• pp.109-116
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• 2018

This research proposed management plan of internal lecturer who is in charge of job training of researchers working in administrative, researching and developing institutes or public institutions related to information security. The education and training department of the government or public institutions selects and manages lecturers in member of the staff. We applied to the management plan of internal lecturers who are in charge of information security job training by analyzing the way in which internal lecturers are operated by public organizations or corporations. We propose the management plan of internal lecturer according to the position, because the institute of information security is applying the researcher 's position(rank) system. By the proposed circulation management plan by the position, the internal lecturer position is determined according to the position of the employees to be trained and the internal lecturer is selected and operated only at the same position. The proposed management plan includes internal lecturer selection, responsibilities and duties, education, evaluation, and training support.

• 기술경영경제학회:학술대회논문집
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• 기술경영경제학회 1998년도 제13회 하계학술발표회 논문집
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• pp.131-163
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• 1998

The interest in the evaluation of government-sponsored research institutes (GRIs) has increased markedly in Korea in 1990s; this is mainly because of the increasing needs 1) to improve the quality of R&D at GRIs, and 2) to reorient the GRIs' strategic position in Korean national innovation systems due to the enhancement of R&D capabilities of private companies and universities during last decade. As a first attempt to diagnose the managerial and strategic issues of GRIs, a Multi-Ministerial Evaluation Committee was established as an ad hoc task force under the Prime Minister's Office in 1991. According to the recommendations of the committee, the Ministry of Science and Technology (MOST) to which most of GRIs were affiliated, made it a rule to evaluate the annual performance of GRIs since 1992. This paper examines the recent experience of MOST's evaluation of Government-sponsored Research Institute in Korea. After several years'efforts of Science & Technology Policy Institute(STEPI) to build prospective evaluation systenL MOST decided to apply two supplementary approaches for the evaluation of GRIs; one is summative annual evaluation and the other is formative 3-year evaluation. The annual evaluation system that is designed as a temporary measure is to monitor and to guide the self-evaluation activities of GRIs. In the process of annual evaluation, MOST tries to minimize its direct involvement, and allows each GRI to develop self-evaluation system that is most appropriate for the unique characteristics of the institute. If there exist urgent issues under scrutiny, however, it can be incorporated and examined by a group of external experts as special issues in the annual evaluation system. The aim of 3-year evaluation is both to examine the past performance of each GRI and to investigate whether the strategic role of each GRI is viable in the future. Its major focus, however, lies not on auditing past performance but on strengthening future strategic position of each GRI. The MOST designates a group of evaluation experts with appropriate knowledge and competence as members of the General Evaluation Committee for one year. With the help of STEPI, a specialized research institute for R&D evaluation, the General Evaluation Committee develops methodology and procedures for the actual evaluation of GRIs. Based on the evaluation reports and recommendations from the General Evaluation Committee, the MOST develops various policy measures for strengthening GRIs.