• 천문학회보
• /
• 제37권2호
• /
• pp.228.1-228.1
• /
• 2012

Digital waveform generation technology for SAR payload can be divided into DDS(Direct Digital Synthesizer) method and Memory Mapped(M/M) method. DDS is the single chip which consists of the Sine Table, NCO(Numerically Controlled Oscillator), DAC, and so on. DDS method is a very simple method because the circuit configuration is not complex but has a disadvantage that can not control phase and amplitude easily by using NCO. M/M method has the complexity of the circuit configuration because it requires the memories which stores the waveforms, the control circuits, and DAC. And this method should apply the high interface technology for being compatible with the wide bandwidth of the digital signal and has the difficulty for PCB design because the number of the signal lines should be increased according to the number of the data bits for DAC. Although it has several disadvantages, this method has the capability of pre-distortion function which can compensate the phase and amplitude characteristics of the system and also has an excellent advantage to make any arbitrary waveform, so this method is considered as an important technology with DDS method. This research describes the technological trends of the waveform generator for the SAR payload and analyzes the characteristics of the technology.

• 대한원격탐사학회지
• /
• 제39권1호
• /
• pp.111-127
• /
• 2023

In visual slam and 3D data modeling, the Iterative Closest Point method is a primary fundamental algorithm, and many technical fields have used this method. However, it relies on search methods that take a high search time. This paper solves this problem by applying an effective point cloud refinement method. And this paper also accelerates the point cloud registration process with an indexing scheme using the spatial decomposition method. Through some experiments, the results of this paper show that the proposed point cloud refinement method helped to produce better performance.

• 한국정보디스플레이학회:학술대회논문집
• /
• 한국정보디스플레이학회 2002년도 International Meeting on Information Display
• /
• pp.115-117
• /
• 2002

In order to realize a stable rubbing process for the liquid crystal panel, the authors investigated the quantitative evaluation method of rubbing process uniformity. The proposed method focuses on the relationship between the image quality of the LCD panel for gray scale images and the rubbing uniformity. The proposed method indicates rubbing uniformity using quantitative parameters of spots and hairlines on the LCD panel.

• 분석과학
• /
• 제28권3호
• /
• pp.160-167
• /
• 2015

이 연구에서는 화장품 중 사용한도 성분으로 지정되어 있으나 아직 분석방법이 개발되지 않은 살균 보존 성분으로 사용되는 zinc pyrithione (ZnPT)에 대한 분석방법을 개발 확립하기 위한 목적으로 국 내외 자료 및 문헌을 조사하여 분석방법을 설정하였으며, 분석방법의 유효성 확인에 필요한 base matrix 시료의 선정을 위해 대상성분들의 사용량 및 사용제품들에 대한 자료를 조사하였다. Base matrix 시료를 선정·제조한 후 분석방법 유효성 확인 절차에 따라 각 대상성분들에 대한 분석방법의 유효성을 확인하였으며 실험실간 분석방법의 유효성 확인 수행을 통해 개발된 분석방법을 검증하여 확립하였다. 최종적으로 실제 시중 유통 화장품을 대상으로 개발된 분석방법을 적용하여 분석방법의 적합성을 검증하였다. 이 연구를 통해 개발된 분석방법을 '화장품 중 배합한도 성분 분석법 가이드라인'으로 제시함으로서 국내 시장 유통화장품의 검정에 활용되어 품질의 향상 및 국민 보건 안전성이 증진될 것이며 국내 화장품 산업의 국제 경쟁력 강화로 인해 수출 증대에 기여할 것으로 기대된다.

• 한국약용작물학회지
• /
• 제16권6호
• /
• pp.446-454
• /
• 2008

An advanced extraction method by ultrasonic extraction with applied solid phase extraction (SPE) has been developed for the determination of simultaneous eight major ginsenosides, namely ginsenosides Rg1, Re, Rf, Rb1, Rg2, Rc, Rb2, and Rd in the root of Panax ginseng. Four extraction methods including n-BuOH reflux extraction (Method A), 70% EtOH reflux extraction (Method B), 50% MeOH reflux extraction with SPE (Method C), and 50% MeOH ultrasonication with SPE clean-up process (Method D) were investigated for the determination of eight major ginsenosides. Total contents of ginsenosides were highest by extraction of Method C as $2.408{\pm}0.011%$. However, Method D was evaluated as relatively simpler and more efficient method due to short extraction time, small solvent consumption and less expensive, compared to conservative reflux method. Ginsenosides were also satisfactorily separated with good resolution and the accuracy range was between 1.05 and 4.06% as relative standard deviation (RSD) by Method D. SPE condition and HPLC condition were further optimized for determination of eight major ginsenosides by the ultrasonic extraction method. Conclusively, ultrasonic extraction of 2 g sample of ginseng using ultrasonic bath and 1 loading for SPE was evaluated as proper condition for extraction of ginseng.

• 한국가정과교육학회지
• /
• 제7권2호
• /
• pp.91-101
• /
• 1995

The purposes of the study were to: (1) develop instructional method for consumer education of home economics in the middle school. (2) test the effectiveness of the developing instructional method focusing on the problem solving. In the method of the research, literature review related to the consumer education. models of teaching and characteristics of problem solving method were studied. Also, on the basis of theoretical evidence. the teaching plan focusing on problem solving method was developed. In addition, experimental research was done to find out the learning effectiveness on the developing instructional method of the study. This experimental research were made in the six classes of the three middle school in Seoul. For the statistical analysis of the study, frequency, mean and two way ANOVA(factorial design) were used. The results of this study were summarized as follows; (1) The developed instructional method of the study was more effective than the traditional lecture method. (2) The effects of the teaching-learning method were depended on the sex. The learning effects on the female students were higher than the male students. (3) The learning effects on the students were influenced by the sex and teaching method.

• 보존과학연구
• /
• 통권20호
• /
• pp.21-47
• /
• 1999

According to damage of papers by the chemical cause, papers become to acidify. Among the 3 kinds of method measuring the acidity of paper, one was nondestructive method measuring the surface of the paper by flat type electrode and the others were destructive methods measuring directly by cold water extract method and hot water extract method. In case of the cellulolytic cultural properties, the latter methods were not applied because those methods must bedissociated papers. To measure the paper acidity nondestructively, we investigated the correlation of the nondestructive method and the destructive methods. The conclusions are as follows. 1) In the relationship of the cold water extract method and the hot water extract method, It was indicated that the pH measured by the hot water extract method was high quality printing paper 0.08, rough printing paper 0.13, and Korean paper 0.29 higher than that by the cold water extract method.2) In the relationship of the cold water extract method and the surface measurement method, It showed that the pH value measured by the cold water extract method was high quality printing paper 1.86, rough printing paper 0.80,and Korean paper 0.58 higher than value that by the surface measurement.3) In the relationship of the hot water extract method and the surface measurement method, It showed that the pH value measured by the hot ABSTRACT water extract method was high quality printing paper 1.78, rough printing paper 0.66, and Korean paper 0.29 higher than that by the surface measurement. From the above-mentioned results, the pH value measured by the surface measurement was need to high about 1.78∼1.86 in high quality printing paper, 0.66-0.80 in rough printing paper, and 0.29∼0.58 in Korean paper and the surface measurement with flat type electrode was very available to measure the acidity of Korean papers actually.

• 펄프종이기술
• /
• 제36권4호
• /
• pp.33-40
• /
• 2004

A white light interferometery (WLI) method for investigating surface microstructure was introduced. Brief description of the principle of this method was provided. The surface structure of various samples, for example, a liner board paper, a pigment coated paper, a intaglio printed paper and a polymer laminated paper were tested and characterized with the WLI method. The data showed the WLI method provided very detailed information about surface topography, which were little affected by the surface condition such as color, opacity, roughness, etc. The data stitching mode of the WLI method could provide high spatial resolution over a large field-of-view, which made it possible to obtain the statistically valid results. Fast and high repeatability also made this method a promising way for investigating the surface micro-structure of paper products and prints.

• 한국물환경학회지
• /
• 제28권5호
• /
• pp.693-703
• /
• 2012

Load Duration Curve(LDC) is a useful tool for analyzing water quality characteristics under various stream flow conditions. This study investigated the methods to identify impaired waterbodies in the assessment of water quality goal attainment by using LDC for the management of Total Maximum Daily Loads (TMDLs). Three methods were proposed. Non-typical regime exclusion method is a method to exclude water quality observations in the non-typical extreme flow conditions in order to minimize the influence of non-ordinary water quality. Flow regime weighted average method is a method to calculate weighted mean water quality instead of arithmetic mean in order to consider water characteristics properly on stream flow regime in addition to the effect of Non-typical regime exclusion method. Load exceeded interval comparison method is a method to compare the intervals between the attained and non-attained load duration periods on the LDC. The assessment of water quality goal attainment can be performed more reasonably and precisely considering water quality variations on stream flow conditions by applying these proposed methods.

• Journal of Electrical Engineering and Technology
• /
• 제6권5호
• /
• pp.666-670
• /
• 2011

In this paper, a method for detecting broken rotor bar and stator winding fault in a low voltage squirrel-case induction motor using an air-gap flux variation analysis is proposed to develop a simple and low cost diagnosis technique. To measure the leakage flux in radial direction, a radial flux sensor is designed as a search coil and installed between stator slots. The proposed method is able to identify two kinds of motor faults by calculating load condition of motors and monitoring abnormal signals those are related with motor faults. Experimental results obtained on 7.5kW three-phase squirrel-cage induction motors are discussed to verify the performance of the proposed method.