• 한국환경과학회지
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• 제16권10호
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• pp.1127-1137
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• 2007

We focused on effects on data assimilation of simulated wind fields by using upper-air observations (wind profiler and sonde data). Local Analysis Prediction System (LAPS), a type of data assimilation system, was used for wind field modeling. Five cases of simulation experiments for sensitivity analysis were performed: which are EXP0) non data assimilation, EXP1) surface data, EXP2) surface data and sonde data, EXP3) surface data and wind profiler data, EXP4) surface data, sonde data and wind profiler data. These were compared with observation data. The result showed that the effects of data assimilation with wind profiler data were found to be greater than sonde data. The delicate wind fields in complex coastal area were simulated well in EXP3. EXP3 and EXP4 using wind profiler data with vertically high resolution represented well sophisticated differences of wind speed compared with EXP1 and EXP2, this is because the effects of wind profiler data assimilation were sensitively adjusted to first guess field than those of sonde observations.

• 한국기계가공학회지
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• 제7권1호
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• pp.47-52
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• 2008

We present a 3-D profiler specially devised for the profile measurement of rough surfaces that are difficult to be measured with conventional non-contact interferometer. The profiler comprises multiple two-point-diffraction sources made of single-mode optical fibers. Test measurement proves that the proposed profiler is well suited for the warpage inspection of microelectronics components with rough surface, such as unpolished backsides of silicon wafers and plastic molds of integrated-circuit chip package.

• 한국환경과학회지
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• 제19권8호
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• pp.983-999
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• 2010

Wind power energy is one of the favorable and fast growing renewable energies. It is most important for exact analysis of wind to evaluate and forecast the wind power energy. The purpose of this study is to improve the performance of numerical atmospheric model by data assimilation over a complex coastal area. The benefit of the profiler is its high temporal resolution and dense observation data at the lower troposphere. Three wind profiler sites used in this study are inhomogeneously situated near south-western coastal area of Korean Peninsula. The method of the data assimilation for using the profiler to the model simulation is the three-dimensional variational data assimilation (3DVAR). The experiment of two cases, with/without assimilation, were conducted for how to effect on model results with wind profiler data. It was found that the assimilated case shows the more reasonable results than the other case compared with vertical observation and surface Automatic Weather Station(AWS) data. Although the effect of sonde data was better than profiler at a higher altitude, the profiler data improves the model performance at lower atmosphere. Comparison with the results of 4 June and 5 June suggests that the efficiency with hourly assimilated profiler data is strongly influenced by synoptic conditions. The reduction rate of Normalized Mean Error(NME), mean bias normalized by averaged wind speed of observation, on 4 June was 28% which was larger than 13% of 5 June. In order to examine the difference in wind power energy, the wind power density(WPD) was calculated and compared.

• Asian Journal of Atmospheric Environment
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• 제4권3호
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• pp.198-210
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• 2010

Precise analysis of local winds for the prediction of atmospheric phenomena in the planetary boundary layer is extremely important. In this study, wind profiler data with fine time resolution and density in the lower troposphere were used to improve the performance of a numerical atmospheric model of a complex coastal area. Three-dimensional variational data assimilation (3DVAR) was used to assimilate profiler data. Two experiments were conducted to determine the effects of the profiler data on model results. First, we performed an observing system experiment. Second, we implemented a sensitivity test of data assimilation intervals to extend the advantages of the profiler to data assimilation. The lowest errors were observed when using both radio sonde and profiler data to interpret vertical and surface observation data. The sensitivity to the assimilation interval differed according to the synoptic conditions when the focus was on the surface results. The sensitivity to the weak synoptic effect was much larger than to the strong synoptic effect. The hourly-assimilated case showed the lowest root mean square error (RMSE, 1.62 m/s) and highest index of agreement (IOA, 0.82) under weak synoptic conditions, whereas the statistics in the 1, 3, and 6 hourly-assimilated cases were similar under strong synoptic conditions. This indicates that the profiler data better represent complex local circulation in the model with high time and vertical resolution, particularly when the synoptic effect is weak.

• 한국정밀공학회지
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• 제19권3호
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• pp.39-45
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• 2002

A simple and low cost stylus profiler made of ferrite cores is developed. The devised profiler consists of a contact probe, a measuring transducer, a signal processing unit, and a motorized stage. The contact probe attached to 4-bar spring maintains sufficient stiffness to protect disturbances. An overlap-area type inductive position sensing system is selected as a measuring transducer, which has high sensitivity, repeatability and linearity. The transducer is composed of coil bundles and ferrite cores which have good electromagnetic characteristics in spite of low cost. The repeatability of the profiler with the proposed inductive sensing system is better than 50nm. Experimental results are shown that the proposed profiler can measure the line or 3D profile of an object with sub-micron features.

• 한국컴퓨터정보학회논문지
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• 제12권2호
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• pp.29-36
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• 2007

자바에서는 가상기계와 프로파일러의 통신을 목적으로 JVM TI 같은 프로파일러 인터페이스를 제공한다. 그러나 자바 가상기계 구현명세는 프로파일러 인터페이스 구현을 요구하지 않는다. 따라서 프로파일러 인터페이스를 제공하지 않는 자바 가상기계에서는 JVM TI를 사용하는 프로파일러는 이용할 수 없다. 이러한 문제를 해결하기 위해서 코드 삽입 기법을 이용해서 프로파일러 인터페이스를 사용하지 않고 힙 사용정보를 분석하는 기법을 제안한다. 제안한 방법을 검증하기 위해서 코드 삽입기를 구현하였다. 실험은 공개되고 자주 사용되는 자바 응용 프로그램을 대상으로 하였고, 실험결과는 대상 프로그램에서 생성된 객체의 수와 최대 할당된 객체의 수 그리고 객체의 사용형태를 보여준다.

• 정보보호학회논문지
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• 제24권1호
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• pp.145-154
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• 2014

본 논문에서는 범죄수사에서 사용되는 프로파일링 기법을 이용한 모바일 악성코드 행위 프로파일링을 통하여 효율적인 모바일 악성코드 분류 방법론 Andro-profiler를 제안한다. Andro-profiler는 클라이언트/서버 형태로, 클라이언트 앱이 모바일기기에 설치되어 사용자가 사용하고 있는 앱에 대한 정보를 서버에 전송하고, 서버에서는 해당 앱을 동적 분석 도구인 Droidbox가 설치된 에뮬레이터에서 실행시키면서 발생되는 시스템 콜과 에뮬레이터 로그를 이용하여 해당 앱의 행동을 프로파일링하며, 해당 앱의 프로파일링 목록을 저장된 악성코드 프로파일링 DB와 비교하여 악성유무를 판단하고, 악성코드로 판단될 경우 분류를 실시하여 클라이언트에게 결과를 통보한다. 실험결과, Andro-profiler는 1MB의 악성코드를 분류하는데 평균 55초가 소요되었고, 99%의 정확도로 악성코드를 분류하는 것을 확인하였으며, 기존 방법론보다 더 정확하게 악성코드를 분류할 수 있다.

• 대한기계학회논문집A
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• 제32권4호
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• pp.297-302
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• 2008

We present an electrical particle velocity profiler using particle transit time across uneven inter-gap electrodes. We measure both the particle position and velocity from the voltage signals generated by the particles passing across sensing electrodes, thus obtaining the velocity profile of the particles in a microfluidic channel. In the experimental study, we use polystyrene microparticles to characterize the performance of the electrical particle velocity profiler. The particle velocity profile is measured with the uncertainty of 5.44%, which is equivalent to the uncertainty of 5% in the previous optical method. We also experimentally demonstrate the capability of the present method for in-channel clogging detection. Compared to the previous optical methods, the present electrical particle velocity profiler offers the simpler structure, the cheaper cost, and the higher integrability to micro-biofluidic systems.

• 정보처리학회논문지:컴퓨터 및 통신 시스템
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• 제4권8호
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• pp.239-244
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• 2015

자바스크립트 상에서 높은 연산량을 처리하기 위해 제안된 WebCL은 불특정 클라이언트 환경에서 실행되므로 개별 클라이언트에서 애플리케이션의 성능 평가 작업이 중요하다. 현재 다양한 프로파일러들이 서비스 되고 있지만 WebCL을 위한 프로파일러는 아직 개발되어있지 않다. 본 논문에서는 웹 이기종 병렬컴퓨팅 언어인 WebCL 기반으로 구현된 애플리케이션의 성능 평가 및 GPU 상태 정보를 모니터링 하기 위한 프로파일러를 설계 및 구현하여 소개한다. 본 프로파일러를 통하여 사용자는 WebCL 기반 애플리케이션의 수행시간 및 메모리 읽기/쓰기 시간을 알 수 있고, GPU 디바이스의 소비 전력, 현재 온도, 클락 속도 등 현재 상태를 실시간 모니터링할 수 있다.

• 한국도로학회논문집
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• 제14권6호
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• pp.45-55
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• 2012

PURPOSES : Skid resistance and noise of roads highly depend on the characteristics of pavement texture. Therefore, estimation of texture characteristics may give useful information for the skid resistance and noise of road. Generally, Sand Patch Test is performed in order to estimate MTD(Mean Texture Depth). However, it is time-consuming and needs traffic control. This study aimed to investigate the effectiveness of measurement texture depth using the Portable Laser Profiler that give the MPD(Mean Profile Depth). METHODS : MTD and MPD were collected on the number of expressway sections including Central Inland Test Road sections in Korea. Statistical analysis are performed to establish the relationship between MTD data based on Sand Patch Test and MPD data obtained by the Portable Laser Profiler. RESULTS : Linear relationship MPD and MTD is observed for both of asphalt pavement and concrete pavement such as R-square of 0.51 to 0.58. CONCLUSIONS : Even though, the test method and definition of MPD and MTD are different. EMTD(Estimated Mean Texture Depth) can be obtained by using the correlationship between MPD with MTD.