• 한국군사과학기술학회지
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• 제6권2호
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• pp.55-64
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• 2003

Underwater acoustic noise measurement is an essential element for vulnerability assessment of modern naval platforms. But during the last few decades environmental conditions have drastically changed due to the gradually increasing sea ambient noise level and decreasing submarine radiated noise level. A real-time underwater acoustic measurement system with vertical line array is designed for the quiet submarine radiated noise assessment in challenging environment. This system has a constant directivity index in measurement frequency range and accurate tracking capability for the transmission loss compensation and navigation aids inside the submarine. This system has been validated at sea and used several times for the submarine noise measurement.

• Smart Structures and Systems
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• 제30권3호
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• pp.287-301
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• 2022

The machine-vision based structural displacement measurement methods are widely used due to its flexible deployment and non-contact measurement characteristics. The accuracy of vision measurement is directly related to the image resolution. In the field of computer vision, super-resolution reconstruction is an emerging method to improve image resolution. Particularly, the deep-learning based image super-resolution methods have shown great potential for improving image resolution and thus the machine-vision based measurement. In this article, we firstly review the latest progress of several deep learning based super-resolution models, together with the public benchmark datasets and the performance evaluation index. Secondly, we construct a binocular visual measurement platform to measure the distances of the adjacent corners on a chessboard that is universally used as a target when measuring the structure displacement via machine-vision based approaches. And then, several typical deep learning based super resolution algorithms are employed to improve the visual measurement performance. Experimental results show that super-resolution reconstruction technology can improve the accuracy of distance measurement of adjacent corners. According to the experimental results, one can find that the measurement accuracy improvement of the super resolution algorithms is not consistent with the existing quantitative performance evaluation index. Lastly, the current challenges and future trends of super resolution algorithms for visual measurement applications are pointed out.

• Journal of Biosystems Engineering
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• 제30권2호
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• pp.127-133
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• 2005

Precision tillage is designed to till lands variably according to their firmness. Therefore, it is necessary to measure soil firmness in fields and present it in a form with which the variable tillage on be performed. Such forms may be classified into two categories: sensor-based and map-based forms. The map-based approach appears to be inevitable until the technology develops high enough to secure the sensor-based approaches. The first step for map-based precision tillage may be to develop a tillage recommendation map. In this study, a tractor-mountable automatic soil firmness measurement system was developed to construct a cone index map. The system is comprised of three ASAE Standard cone penetrometers and a hydraulic unit for controlling operation of the penetrometers. The system is designed to conduct stop-and-go measurements in fields. The measurements from the three penetrometers are transferred to a microcomputer and the average cone index was calculated. This average cone index was taken as soil firmness of the location where the measurement was made. The cone indices thus determined were used to construct a cone index map using the ArcView software. The system also displays the soil penetration resistance, cone index and soil depth as the cone penetrates into the soil. The field performance of the system was evaluated and the cone index maps at different depths were also presented.

• 한국광학회지
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• 제21권5호
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• pp.190-194
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• 2010

본 연구에서는 측면연마 된 광섬유 브래그 격자를 측면 연마하고 폴리머 상부층(overlay)를 형성시켜 외부 굴절률과 온도를 동시 측정할 수 있는 광섬유 센서 소자를 제안하였다. 외부굴절률 변화에 민감하지 않는 광섬유 브래그 격자를 이용하여 온도를 측정하고 격자를 측면 연마한 후 폴리머 코팅에 의해 소산장 결합을 유도하여 외부 굴절률 변화를 측정하게 된다. 측면 연마된 광섬유 브래그 격자의 온도 민감도는 0.01 nm/oC로 측정되었고 폴리머 상부층의 온도 민감도는 -0.58 nm/oC로 측정되었고 선형구간 별(1.33-1.39, 1.39-1.42, 1.42-1.44) 굴절률 민감도는 498.8 nm/RIU, 694.9 nm/RIU, 1312 nm/RIU로 측정되었다.

• 한국방사선학회논문지
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• 제14권6호
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• pp.791-800
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• 2020

태아 심장의 기능을 평가하기 위해 초음파 검사가 널리 이용되고 있으나 주관적이라는 검사의 특성으로 인해 검사자마다 측정 방식에 차이가 있으며 특히 심근 성능 지수는 현재까지 기준치가 없는 실정이다. 이에 본 연구에서는 정상 태아의 펄스 도플러 파형을 분석하여 자동 측정 프로그램을 개발하여 객관적인 측정을 하고자 하였다. 2019년 4월부터 2020년 2월까지 부산에 위치한 W병원에 내원한 산모 133명을 대상으로 태아 심장 초음파검사를 시행하였으며 좌심실의 펄스 도플러 영상을 획득 후 각 심근 성능 지수를 측정하였다. 본 연구에서 구현한 자동 측정 프로그램을 이용한 임신 초기, 중기, 말기의 심장 성능 지수와 기존의 측정 방식을 이용한 심장 성능 지수를 비교한 결과, 두 수치에는 차이가 있었으나 같은 경향성을 보였다.

• 설비공학논문집
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• 제17권11호
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• pp.1088-1094
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• 2005

In the present paper, a new method is proposed for the measurement of the ice packing factor (IPF) of an ice slurry using the index of refraction. The purpose of the new method is to improve the resolution of the measurement and to increase its resistance to electric noise as compared to the standard IPF measurement technique that relies on measurement of the freezing temperature. These two methods are similar in that they both obtain a concentration of aqueous solution from measured physical quantities and calculate the IPF using a relation between concentration and IPF. We experimented and compared the two methods, whose results were also compared with results from the calorimeter method obtaining the IPF directly They are in good agreement (within $5\%$), which demonstrates the validity of the newly proposed method.

• 정보화연구
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• 제10권2호
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• pp.237-249
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• 2013

그간 우리나라에서는 한국은행, 삼성경제연구소, 대한상의 등에서 기업가정신 측정모델을 발표한 바 있으나, 각 기관의 임의적인 측정모델 개발 및 단편적인 조사로 인해, 우리나라 기업가정신 측정 및 이해에 혼선이 초래되었다. 아울러, 기업가정신지수에 대한 국내외 비교연구의 부재로 글로벌 기업가정신지수 모델 수립이 현실적으로 어려웠다. 이에 본 연구에서는 무엇보다 기존 기업가정신 지수 관련 국내외 연구에 대한 선행연구분석과 이를 기초로 한 기업가정신 지수 모델, 즉, 기업가정신의 객관적 측정과 국제적 비교를 가능하게 하는 공통지표를 제시했다. 무엇보다 기존 연구 내용 및 장단점을 체계적으로 정리, 향후 기업가정신 지수의 방향성을 제안했다.

• 한국소음진동공학회논문집
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• 제15권8호
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• pp.939-944
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• 2005

In this paper, a sound quality index for the evaluation of the vehicle intake noise was developed through a correlation analysis of the objective measurement and the subjective evaluation. First, intake orifice noise was measured at the wide-open throttle sweep condition. And then, the acoustic transfer function between intake orifice noise and interior noise was measured. Simultaneously, subjective evaluation was carried out with a 10-scale score by 8 special engineers. The correlation analysis between the psychoacoustic parameters derived from the measurement and the subjective evaluation was performed. The most critical factor was determined and the corresponding sound quality index for intake noise was obtained from the multiple factor regression analysis method. Finally, the effectiveness of the proposed index was validated.

• 한국전기전자재료학회논문지
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• 제28권8호
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• pp.513-517
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• 2015

We proposed and demonstrated a simultaneous measurement method to detect the refractive index and temperature of a medium using a side-polished fiber involving FBG (fiber Bragg grating). The temperature of a medium was obtained by using the Bragg wavelength shift of FBG, while the refractive index of medium were calculated by using the transmission loss. The Bragg wavelength is independent on the refractive index of the covering medium placed on surface of side-polished fiber, while the transmission loss at off-Bragg wavelength highly depends on the environmental temperature because of thermo-optic effect of the medium.

• 한국콘텐츠학회논문지
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• 제19권5호
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• pp.115-127
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• 2019

본 연구는 지방자치단체가 수행하는 다양한 보조사업 중 장애인편의시설설치촉진사업에서 효과적이고 효율적인 성과관리 평가체계구축의 필요성과 실효성에 대해 논의하였다. 이와 함께 사회서비스 영역에서 성과평가시스템을 도입하면서 논리적 구조로 활용되는 논리모형을 적용하여 사회복지시설평가영역에 포함되지 않는 장애인편의시설설치촉진사업의 성과관리 평가지표를 개발함을 목적으로 한다. 이를 위해 문헌검토와 초점집단인터뷰를 통해 성과관리 평가지표를 개발하고 시범평가를 통해 평가지표의 타당성 및 평가용이성 분석을 실시한 후, 시범평가결과를 바탕으로 현장의견조사 및 전문가를 통한 타당성 검토를 진행하여 최종지표를 개발하였다. 최종 개발된 평가지표는 전체 8개 영역, 39개 문항으로 구성되었다. 장애인편의시설설치촉진사업 성과관리 평가체계 구축을 통해 장애인편의시설설치촉진사업 전반의 합리화를 추구하고자 하였으며, 본 연구에서 제시된 성과관리 평가지표의 개념틀과 평가접근 방식은 공공부문의 다양한 사회서비스 유형과 특성에 적합하게 활용될 수 있을 것이다.