• Journal of Sensor Science and Technology
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• v.33 no.4
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• pp.187-195
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• 2024

Light detection and ranging (LiDAR), a widely used sensor in mobile robots and autonomous vehicles, has its most important function as measuring the range of objects in three-dimensional space and generating point clouds. These point clouds consist of the coordinates of each reflection point and can be used for various tasks, such as obstacle detection and environment recognition. However, several processing steps are required, such as three-dimensional modeling, mesh generation, and rendering. Efficient data processing is crucial because LiDAR provides a large number of real-time measurements with high sampling frequencies. Despite the rapid development of controller computational power, simplifying the computational algorithm is still necessary. This paper presents a method for estimating the presence of curbs, humps, and ground tilt using range measurements from a single horizontal or vertical scan instead of point clouds. These features can be obtained by data segmentation based on linearization. The effectiveness of the proposed algorithm was verified by experiments in various environments.

• Journal of the Korean Home Economics Association
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• v.29 no.1
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• pp.27-35
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• 1991

This study was carried out to investigate the influence of the various physiological function caused by brassiere wearing. The four experimental methods used in this study are as follows. For example, the Roentgen photographing, Body measurement by Sliding Gauge, the measurement of the Electrocardiogram and Blood Pressure. The results of the Electrocardiogram and Blood Pressure. The results of the investigation were as follows: 1. In experimental change by Sliding Gauge and Body measurement, The bust point was rised in order AB1>B2. The width of right and left bust point was decreased in order of A>B1>B2. According to, The supplementary effect of brassiere wearing was excellent in B2. 2. In the change of various organs by Roentgen photographing, The width of the chest and size of the heart were decreased in regular order of A>B1>B2. The diaphragm and the others were not showed change. 3. In the experimental result by measurement of the electrocardiogram, The interval of heart palpitation was decreased in order A>B1>B2 and the pulse frequency was similar. 4. In the experimental result by the blood pressure measurement, A had the highest blood pressure and B2 had the lowest pressure in all variables.

• Proceedings of the Korean Information Science Society Conference
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• 2010.11a
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• pp.36-37
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• 2010

• Korean Management Science Review
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• v.19 no.2
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• pp.191-204
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• 2002

As the portion of information systems (IS) budget to the total government budget becomes greater, the cost estimation of IS development and maintenance projects is recognized as one of the most important problems to be resolved for scientific and efficient management of IS budget. Since IS budget makes much effect on the delivery time, quality and productivity of IS projects, the exact cost estimation is also necessary for the successful accomplishment of IS projects. The primary concern in the cost estimation of IS projects is software cost estimation, which requires the measurement of the size of softwares. There are two methods for sizing software : line-of-code approach, function point model. In this paper, we propose a function-point-based model for estimating software cost. The proposed model is derived by collecting about fifty domestic IT projects in public sector and analyzing their relationship between cost drivers and development effort. Since the proposed model is developed by simplifying the function point model that can be used only when detailed user requirements are specified, it can be also applied at project planning and budgeting phase.

• Proceedings of the KIEE Conference
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• 2003.11c
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• pp.916-919
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• 2003

In this paper, we deal with a development of measurement system to apply the leakage rates test of primary containment in nuclear power plant. The measurement test about leakage rates in primary containment is one sort of test to prove safety of nuclear power plant. The parameters which are measured to calculate leakage rates are drybulb temperature, dew point temperature(or relative humidity), absolute pressure and flow. Overall, the measurement system consists of sensor module for data acquisition of the parameters, transfer module for wireless data communication and control module to control system and to calculate leakage rates. Because existing measurement systems are difficult to set in field, we pursued convenience of use, we applied wireless data communication and individual form module using battery. We also changed for the better in confidence. Recently, we are developing a drybulb temperature and a dew point temperature sensor module. We describe about function of developed measurement system, its standard and an plan for verification of measurement system.

• Journal of the Optical Society of Korea
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• v.16 no.4
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• pp.372-380
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• 2012

The optical method Digital Speckle Correlation Measurement (DSCM) has been extensively applied due its capability to measure the entire displacement field over a body surface. A formula of displacement measurement errors by the gradient-based DSCM method was derived. The errors were found to explicitly relate to the image grayscale errors consisting of sub-pixel interpolation algorithm errors, image noise, and subset deformation mismatch at each point of the subset. A power-law dependence of the standard deviation of displacement measurement errors on the subset size was established when the subset deformation was rigid body translation and random image noise was dominant and it was confirmed by both the numerical and experimental results. In a gradient-based algorithm the basic assumption is rigid body translation of the interrogated subsets, however, this is in contradiction to the real circumstances where strains exist. Numerical and experimental results also indicated that, subset shape function mismatch was dominant when the order of the assumed subset shape function was lower than that of the actual subset deformation field and the power-law dependence clearly broke down. The power-law relationship further leads to a simple criterion for choosing a suitable subset size, image quality, sub-pixel algorithm, and subset shape function for DSCM.

• International Journal of Automotive Technology
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• v.7 no.2
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• pp.173-177
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• 2006

A noise transfer function(NTF) is the frequency response function between an input force applied to an exterior point of a vehicle body and the resultant interior sound pressure usually measured at the driver's ear position. It represents the measure of noise sensitivity for the output force transmitted to the joints between the body and chassis. The principle of vibro-acoustic reciprocity is often utilized in the measurement of NTF. One difficulty in using the volume source is that most of the previously proposed methods require the knowledge of the volume velocity of the acoustic source in advance. A new method proposed in the present work does not require any calculation related with the volume velocity of the acoustic source, but still yields even more accurate results both in the amplitude and phase of the NTF. In the present work, the new method is applied to obtain NTF data for a midsize sedan.

• Korean Journal of Computational Design and Engineering
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• v.10 no.2
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• pp.114-120
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• 2005

This paper presents a novel method for radius measurement of fillet regions of polygonal models by using optimum onhogonal planes. The objective function for finding an optimum onhogonal plane is designed based on the orthogonality between the normal vectors of the faces in a filet region and the plane that is to be found. Direct search methods are employed to solve the defined optimization problem since no explicit derivatives of the object function can be calculated. Once an optimum orthogonal plane is obtained, the intersection between the onhogonal plane and the faces of interest is calculated, and necessary point data in the fillet region for measuring radii are extracted by some manipulation. Then, the radius of the fillet region in question is measured by least squares fitting of a circle to the extracted point data. The proposed radius measuring method could eliminate the burden of defining a plane for radius measurement, and automatically find a necessary optimum orthogonal plane. It has an advantage in that it can measure fillet radii without prior complicated segmentation of fillet regions and explicit information of neighboring surfaces. The proposed method is demonstrated trough some mea-surement examples.

• Korean Management Science Review
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• v.27 no.1
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• pp.91-105
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• 2010

We proposed and stratified a selection standard model on Open Source Functional Board which could be found in Web. So we could grasp the weight about Performance Evaluation from the viewpoints of planners, developers, and web disigner professional of views. We suggested applying diverse measurement types in case of item which could chart Evaluation Standards on chosen sample boards. In case of item which couldn't do that, we compared and analyzed it by using selective type of 9 point scaling method on professionalists in every sample board. As a result of weight on upper estimate section of evaluation model chart, the order of importance was convenience(0.334), performance(0.333), function(0.240) and design(0.093) respectively. It indicates that there is more weight on performance and convenience which are hard to be structurally modified than designs and functions that are directly shown to the users. Also, it was evident that opposite results came out when using 9-point scale survey and measurement with objective data such as function and performance. The reason is because the surveyed subject can have his or her own subjectivity and bias unlike objective data. However, objectivity of the administrator is also an important factor thus both two perspectives have to be all considered when selecting the bulletin board.

• Korean Journal of Materials Research
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• v.3 no.4
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• pp.422-423
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• 1993

In this short note, we report the result of measurement for the ferro- to paramagnetic phase transition temperature, that is Curie point of bulk gadolinium. This note is written to give the solid validity for the previous measurement of Curie point shift of gadolinium film (1. Rhee, E. Lee and S. Lee, Kor. J. of Mat. Research,3, 3, 1993). The Curie point of bulk gadolinium is determined by measuring the resistance of sample as function of temperatures. At Curie point, we can observe the resistivity anomaly which arises due to the heat capacity difference between below and above Curie point. Finally, the curie point of bulk gadolinium is found to be 19.2${\pm}$0.$3^{\circ}C$.