• The Journal of the Acoustical Society of Korea
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• v.9 no.4
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• pp.5-17
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• 1990

This study aims to establish the appropriate class and standards of sound insulation performance, which are suitable for domestic conditions. For, these purpose, field surveys were conducted, correlationship between subjective response and impact sound insulation performance and then, the applicability of ISO and JIS evaluation method was reviewed. As a result, the JISs method is more advisable than the ISO to evaluate Impact sound insulation performance of domestic apartment house and it is desirable to use both light and heavy weight source (tapping machine, tire) as standard impact sources. And, whether including 63Hz bandwidth or not, the difference was recognized very small in calculating impact sound insulation index of JIS A 1419.

• Survey Research
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• v.4 no.2
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• pp.47-62
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• 2003

Based upon the Labor Demand Survey and the Survey on Wage Structure being conducted annually by the Ministry of Labor, we suggest a convenient statistical tool which can analyze and appraise the effect of introducing a new survey method. Since both surveys have in common very similar sampling frames and sampling schemes in structure, one can measure the variability of one survey on the basis of the other. The influence appraisal method adopted here is applied to ratio data between two independent estimates belonging to the identical category by year and has a statistical form of comparing ratio data before introducing a new survey with those after introducing a new survey.

• 한국공간정보시스템학회:학술대회논문집
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• 2007.06a
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• pp.233-239
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• 2007

현행 지적도에는 건물 위치가 표시되지 않아 지적도 활용 시 건물 위치 식별이 어렵고, 지적현황측량에 따른 비용과 시간의 소요와 불편을 격고 있으며, 지상 건물의 경계 침범으로 인한 분쟁과 소송이 일어나고 있다. 건축물 경계 추출에 관한 선행연구에서 수치정사사진과 LiDAR를 이용한 건물 경계를 추출은 원칙적으로 지적측량의 원리와 상이한 기준으로 실제 지상의 외벽 경계선이 아닌 건축물의 옥상층 경계선을 추출하였다. 따라서 본 연구에서는 건물등록을 위해 시도해 보지 않았던 건축도면을 이용하여, 기존연구에서 고려되지 못한 지붕선이나 처마선이 아닌 실제 지적측량에서 기준이 되는 외벽의 경계선을 등록하기 위해 건축도면을 활용하였으며, 등록하는 과정에서 ArcGIS 엔진을 이용하여 개발한 자동 등록 방법을 사용하였다. 지적도 필지 경계선과 건축도면의 필지 경계선을 기준으로 등록한 결과 지적현황측량 성과와 수치지역에서 연결오차로 RMSE가 0.10m, 도해지역에서 0.16m로 나타났다. 따라서 건축도면을 이용하여 지적도에 건축물의 경계를 등록함으로써 지상측량을 보완할 수 있으며, 3차원 지적구축을 위한 기반을 조성하고, 지적재조사사업에서 시간과 경비를 획기적으로 절감할 수 있을 것이다.

• Journal of radiological science and technology
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• v.35 no.3
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• pp.249-254
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• 2012

The aim of this study was to investigate the setup accuracy for tangential breast treatment patients using electronic portal image and 2-D reconstruction image Twenty two patients undergoing tangential breast treatment. To explore the setup accuracy, distances between chosen landmarks were taken as reference parameters. The difference between measured reference parameters on simulation films and electronic portal images (EPIs) was calculated as the setup error. A total of 22 simulation films and 110 EPIs were evaluated. In the tangential fields, the calculated reference parameters were the central lung distance (CLD), central soft-tissue distance (CSTD), and above lung distance (ALD), below lung distance (BLD). In the medial tangential field, the average difference values for these parameters were 1.0, -6.4, -2.1 and 2.0, respectively; and the ${\sigma}$ values were 1.5, 2.3, 4.1 and 1.1, respectively. In the lateral tangential field, the average difference values for these parameters were -1.5, -4.3, -2.7 and -1.3, respectively; and the ${\sigma}$ values were 3.3, 2.1, 2.9 and 2.5, respectively. CLD, CSTD, ALD and BLD in the tangential fields are easily identifiable and are helpful for detecting setup errors using EPIs in patients undergoing tangential breast radiotherapy treatment.

• Journal of the Korea Organic Resources Recycling Association
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• v.25 no.3
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• pp.73-78
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• 2017

Objective of this experiment was to evaluate efficiency of application of biochar pellet in case of application of soil carbon sequestration technology. The treatments were consisted of control as general agricultural practice method, pellet(100% pig compost), biochar pellets with mixture ratio of pig compost(9:1, 8:2, 6:4, 4:6, 2:8) for comparatives of pH, EC, $NH_4-N$ and $NO_3-N$ concentrations, and yields in the nursery bed applied biochar pellets after lettuce harvesting. The application rates of biochar pellet was 6.6g/pot regardless of their mixed rates based on recommended amount of application (330kg/10a) for lettuce cultivation. pH in the nursery bed applied different biochar pellets after lettuce harvesting was only increased in the treatment plot of pig compost pellet application, but decreased in 4:6 and 2:8 pellet application plots. However, EC was observed to be not significantly different among the treatments. $NH_4-N$ concentration was only increased in the treatment plot of pig compost pellet application, but $NO_3-N$ concentrations were decreased as compared to the control. Yields in the treatments of 9:1, 8:2 and 4:6 biochar pellet application plot were increased from 9.5% to 11.4%. Therefore, this biochar pellet application might be useful for soil carbon sequestration and greenhouse gas mitigation in the agricultural farming practices because it was appeared to be a positive effect on lettuce growth.

• Journal of the Korean Society of Surveying, Geodesy, Photogrammetry and Cartography
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• v.36 no.6
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• pp.565-572
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• 2018

Recently, UAVs (Unmanned Aerial Vehicles) or drones have gained popularity for the engineering surveying and mapping because they enable the rapid data acquisition and processing as well as their operation cost is low. The applicable fields become much wider including the topographic monitoring, agriculture, and forestry. It is reported that the high geospatial accuracy is achievable with the drone photogrammetry for many applications. However most studies reported the best achievable mapping results using well-distributed ground control points though some studies investigated the impact of control points on the accuracy. In this study, we focused on the drone mapping of corridors such as roads and pipelines. The distribution and the number of control points along the corridor were diversified for the accuracy assessment. In addition, the effects of the camera self-calibration and the number of the image strips were also studied. The experimental results showed that the biased distribution of ground control points has more negative impact on the accuracy compared to the density of points. The prior camera calibration was favored than the on-the-fly self-calibration that may produce poor positional accuracy for the case of less or biased control points. In addition, increasing the number of strips along the corridor was not helpful to increase the positional accuracy.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.12
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• pp.6346-6352
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• 2013

Radiotherapy of rectal cancer requires a stabilized image but the movement of patients is almost unavoidable in radiotherapy. In this study, the setup error using the radiation treatment technique was compared according to the loading time and BMI(Body Mass Index) for 14 patients with rectal cancer. In addition, the variation of the dose by the average setup error was compared. Therefore, the technique of a selective standard was established. As a result, 3DCRT(3-Dimensional Radiation Therapy) and VMAT(Volumetric Modulated Arc Therapy) showed a similar time and error. In comparison, IMRT(Intensity Modulated Radiation Therapy) increased the time two fold and the error four fold. In BMI, a more pyknic patient showed a larger error for all techniques. Regarding the dose, IMRT and VMAT increased much more than 3DCRT in the average error at the small bowel. Therefore, 3DCRT of the short time will be applied to pyknic rectal cancer. Moreover, VMAT selects than IMRT in the overexposure of the small bowel.

• Journal of Korean Ophthalmic Optics Society
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• v.20 no.3
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• pp.385-390
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• 2015

Purpose: This study evaluated the static stereoacuity by Distance Randot Stereotest (STEREO OPTICAL. Co., Inc. USA) and the dynamic stereoacuity by three-rods test (iNT, Korea). Criterion and correlation of stereoacuity between both tests and usefulness of two stereotest methods were also evaluated. Methods: For normal adults of 109 (male 61, female 48), mean age of 20.88 (19-32 years) years old, static stereoacuity by using Distance Randot Stereotest at 3 m distance, dynamic stereoacuity by using three-rods test at 2.5 m distance were measured. Results: The mean of distance static stereoacuity was $155.77{\pm}133.11sec$ of arc and the mean of error distance dynamic stereoacuity $11.13{\pm}9.69mm$. With equivalent-conversion stereoacuity of $23.44{\pm}20.96sec$ of arc, there was statistically significant differences (p=0.00) between two dynamic stereoacuity, but correlation was relatively low (${\rho}=0.226$). In the case of dynamic stereoacuity, separated to normal range by criterion of the error distance 20 mm, it showed the error distance of less than 20 mm in 97 subjects(89%) whose average of error distance and conversion mean dynamic stereoacuity were $8.43{\pm}5.10mm$ and $17.68{\pm}10.67sec$ of arc. repectively. The error distance of was equivalent-conversion dynamic stereoacuity 40.99 sec of arc (PD 62 mm basis) was 20 mm. Conclusions: The results of lower correlation between static and dynamic stereoacuity suggest that seterotest should be applied separately to different functions. The results of this study also suggest that Distance Randot Stereotest can be applied to static stereoacuity excluding monocular cues. Three-rods test can be applied to dynamic stereoacuity containing the response of the eye-hand coordination in the daily life of natural vision condition, including the monocular cues. These different approaches canprovide a criterion of the two stereoacuity and parallel use of the two tests would be useful. For dynamic stereoacuity by three-rods test, error distance 20 mm in a normal range of adults can be used as a criteria to get statistical meaning of the results.

• The Journal of Korean Society for Radiation Therapy
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• v.21 no.1
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• pp.1-7
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• 2009

Purpose: The purpose is to evaluate the accuracy of correcting the targeting error through the Target Location System (TLS) for the location change error of the reference point which arises from the movement or motion of patient during the treatment using the CyberKnife. Materials and Methods: In this test, Gafchromic MD-55 film was inserted into the head and neck phantom to analyze the accuracy of the targeting, and then the 6 MV X-ray of CyberKnife (CyberKnife Robotic Radiosurgery System G4, Accuray, US) was irradiated. End to End (E2E) program was used to analyze the accuracy of targeting, which is provided by Accuray Corporation. To compute the error of the targeting, the test was carried out with the films that were irradiated 12 times by maintaining the distance within the rage of $0{\pm}0.2\;mm$ toward x, y, z from the reference point and maintaining the angle within the rage of $0{\pm}0.2^{\circ}$ toward roll, pitch, yaw, and then with the films which were irradiated 6 times by applying intentional movement. And the correlation in the average value of the reference film and the test film were analyzed through independent samples t-test. In addition, the consistency of dose distribution through gamma-index method (dose difference: 3%) was quantified, compared, and analyzed by varying the distance to agreement (DTA) to 1 mm, 1.5 mm, 2 mm, respectively. Results: E2E test result indicated that the average error of the reference film was 0.405 mm and the standard deviation was 0.069 mm. The average error of the test film was 0.413 mm with the standard deviation of 0.121 mm. The result of independent sampling t-test for both averages showed that the significant probability was P=0.836 (confidence level: 95%). Besides, by comparing the consistency of dose distribution of DTA through 1 mm, 1.5 mm, 2 mm, it was found that the average dose distribution of axial film was 95.04%, 97.56%, 98.13%, respectively in 3,314 locations of the reference film, consistent with the average dose distribution of sagittal film that was 95.47%, 97.68%, 98.47%, respectively. By comparing with the test film, it was found that the average dose distribution of axial film was 96.38%, 97.57%, 98.04%, respectively, at 3,323 locations, consistent with the average dose distribution of sagittal film which was 95.50%, 97.87%, 98.36%, respectively. Conclusion: Robotic CyberKnife traces and complements in real time the error in the location change of the reference point caused by the motion or movement of patient during the treatment and provides the accuracy with the consistency of over 95% dose distribution and the targeting error below 1 mm.

• Proceedings of the Korean Information Science Society Conference
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• 2002.04a
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• pp.679-681
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• 2002

본 논문에서는 화질 향상을 위한 콘트라스트 조정 기법을 제안한다. 제안한 방식은 기존의 알고리즘을 단순화하여서 실시간 처리가 가능하며 콘트라스트의 범위를 조정하는 가중치를 두었다. 연산을 함에 있어 기준이 되는 값을 선언하여 콘트라스트의 효율적인 조정과 오차율을 줄였다. 제안한 방식에 의한 처리 결과와 원 영상의 화질 평가를 위해 시각적 검증과 히스토그램의 표준 편차를 도입 하였다.