• The Journal of Engineering Geology
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• v.11 no.2
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• pp.205-214
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• 2001

A simple automated measuring method for planar or linear features on the rock excavation surface is presented. Attitude of the planar and linear feature is calculated from 3D coordinates of points on the structures. Spatial coordinates are calculated from overlapped stereo images. Factors used in the calculation are (1) local coordinates of the left and right images, (2) the focal length of cameras, and (3) the distance between two cameras. A simple image capturing device and an image treatment routine coded by Visual Basic and GIS components are constructed for the remote measurements, The methodology shows less than 1 cm error when a point is measured from 179 cm in distance. The methodology is tested at the excavation site in PaiChai University. Remotely measured result matches well with the manual measurement within the reasonable error range.

• The Journal of the Korea Contents Association
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• v.6 no.1
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• pp.31-40
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• 2006

In this paper, we propose a gait recognition method based on gait silhouette sequences. Features of gait are affected by the variation of gait direction. Therefore, we synthesize silhouettes to canonical form by using planar homography in order to reduce the effect of the variation of gait direction. The planar homography is estimated with only the information which exist within the gait sequences without complicate operations such as camera calibration. Even though gait silhouettes are generated from an individual person, fragments beyond common characteristics exist because of errors caused by inaccuracy of background subtraction algorithm. In this paper, we use the Principal Component Analysis to analyze the deviated characteristics of each individual person. PCA used in this paper, however, is not same as the traditional strategy used in pattern classification. We use PCA as a criterion to analyze the amount of deviation from common characteristic. Experimental results show that the proposed method is robust to the variation of gait direction and improves separability of test-data groups.

• Journal of Sensor Science and Technology
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• v.30 no.5
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• pp.342-348
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• 2021

For the characterization or failure analysis of electronic devices such as PCB (printed circuit boards), the most common method is the measurement of voltage waveforms with an oscilloscope. However, because there are many types of problems that cannot be detected by voltage waveform analysis, several other methods such as X-ray transmission, infrared imaging, or eddy current measurement have been applied for these analyses. However, these methods have also been limited to general analyses because they are partially useful in detecting physical defects, such as disconnections or short circuits. Fundamentally current waveform measurements during the operation of electronic devices need to be performed, however, commercially available current sensors have not yet been developed, particularly for applications in highly integrated PCB products with sub-millimeter fine pitch. In this study, we developed a highly sensitive PHR (planar hall resistance) magnetic sensor for application in highly integrated PCBs. The developed magnetic sensor exhibited sufficient features of an ultra-small size of less than 340 ㎛, magnetic field resolution of 10 nT, and current resolution of 1 mA, which can be applicable for PCB analyses. In this work, we introduce the development process of the magnetic sensing probe and its characteristic results in detail, and aim to extend this pin-type current probe to applications such as current distribution imaging of PCBs.

• Proceedings of the IEEK Conference
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• 2002.07c
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• pp.1531-1534
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• 2002

Shape description and its corresponding matching algorithm is one of the main concerns in MPEG-7. In this paper, a new method is proposed for shape registration of 2D objects for MPEG-7 Shapes are recognized using the Hu statistical moments in frequency domain. The Hu moments are moment-based descriptors of planar shapes, which are invariant under general translation, rotational, scaling, and reflection transformation. The image is transformed into frequency domain using Fourier Transform. Annular and radial wedge distributions fur the power spectra are extracted. Different statistical features (Hu moments) are found f3r the power spectrum of each selected transformed individual feature. The Euclidean distance of the extracted moment descriptors of the features are found with respect to the shapes in the database. The minimum Euclidean distance is the candidate for the matched shape. The simulation results are performed on the test shapes of MPEG-7.

• Mycobiology
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• v.37 no.2
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• pp.141-146
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• 2009

Novel copper(II) complexes have been synthesized from the macrocyclic Schiff bases derived from Knoevenagel condensed ${\beta}$-ketoanilides (obtained by the condensation of acetoacetanilide and substituted benzaldehydes), 4-aminoantipyrine and ophenylene diamine. The structural features have been determined from their analytical and spectral data. All the Cu(II) complexes exhibit square planar geometry. Their high molar conductance values support their 1 : 2 electrolytic nature. The magnetic moment data provide evidence for the monomeric nature of the complexes. The X-band ESR spectra of the |$CuL^1$|$(OAc)_2$ in DMSO solution at 300 and 77 K were recorded and their salient features are reported. The in vitro biological screening effects of the investigated compounds were tested against the bacterial species Staphylococcus aureus, Escherichia coli, Klebsiella pneumoniae, Proteus vulgaris and Pseudomonas aeruginosa and fungal species Aspergillus niger, Rhizopus stolonifer, Aspergillus flavus, Rhizoctonia bataicola and Candida albicans by well diffusion method. A comparative study of inhibition values of the Schiff bases and their complexes indicate that complexes exhibit higher antimicrobial activity than the Schiff bases. Copper ions proved to be essential for the growth-inhibitor effect. The extent of inhibition appeared to be strongly dependent on the initial cell density and on the growth medium.

• ALGAE
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• v.34 no.3
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• pp.199-216
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• 2019

Platysiphon verticillatus and Punctaria glacialis are synonymized by mainly on the basis of shared genes, nine identical sequences. Our hypothesis is that synonymy is erroneous. We posit the many differences of biological features between the two species, their ecological preferences, and occurrences do not support synonymy. Arcticophycus (nov. gen.) is described and contains the new combination Arcticophycus glacialis. Asexual, vegetative, life histories are proposed. Novel reproductive structures are described including previously unknown features of thallus development in the life history of both species. Discovery of the novel Platysiphon cyst, and dual sporangia types in Arcticophycus, is critical in establishing a probable strategy for survival through the Arctic winter for each annual species. Pl. verticillatus is erect, tubular, ovoid to circular in X sections, flaccid, non-parenchymatous, light brown, 10-15 cm high with distinctive photosynthetic hairs in clusters or whorled on the upper one third of the thallus. A. glacialis is erect, planar, robust, parenchymatous, dark brown and hairs absent. The Halosiphon clade is named, consisting of four genera: Halosiphon, Platysiphon, Arcticophycus, and Stschapovia. Occurrence of these genera is identified. Emended are the genus Platysiphon, the family Platysiphonaceae and the order Stschapoviales.

• 제어로봇시스템학회:학술대회논문집
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• 2004.08a
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• pp.1920-1925
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• 2004

This paper describes a new method for 3D object recognition which used surface segment-based stereo vision. The position and orientation of an objects is identified accurately enabling a robot to pick up, even though the objects are multiple and partially occluded. The stereo vision is used to get the 3D information as 3D sensing, and CAD model with its post processing is used for building models. Matching is initially performed using the model and object features, and calculate roughly the object's position and orientation. Though the fine adjustment step, the accuracy of the position and orientation are improved.

• 한국HCI학회:학술대회논문집
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• 2008.02a
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• pp.795-800
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• 2008

카메라로 입력되는 영상에서 객체를 인식하기 위한 노력은, 기존의 컴퓨터 비전분야에서 좋은 이슈로 연구되고 있다. 영상 내부에 등장하는 객체를 인식하고 해당 객체를 포함하고 있는 전체 이미지에서 현재 영상의 위치를 인식하기 위해서는, 영상 내에 등장할 객체에 대한 트레이닝이 필요하다. 본 논문에서는 영상에 등장할 객체에 대해서, 특징 점을 검출(feature detection)하고 각 점들이 가지는 픽셀 그라디언트 방향의 벡터 값들을 그 이웃하는 벡터 값들과 함께 DoG(difference-of-Gaussian)함수를 이용하여 정형화 한다. 이는 추후에 입력되는 영상에서 검출되는 특징 점들과 그 이웃들 간의 거리나 스케일의 비율 등의 파리미터를 이용하여 비교함으로써, 현재 특징 점들의 위치를 추정하는 정보로 사용된다. 본 논문에서는 광역의 시설 단지를 촬영한 인공위성 영상을 활용하여 시설물 내부에 존재는 건물들에 대한 초기 특징 점들을 검출하고 데이터베이스로 저장한다. 트레이닝이 마친 후에는, 프린트된 인공위성 영상내부의 특정 건물을 카메라를 이용하여 촬영하고, 이 때 입력된 영상의 특징 점을 해석하여 기존에 구축된 데이터베이스 내의 특징 점과 비교하는 과정을 거친다. 매칭되는 특징 점들은 DoG로 정형화된 벡터 값들을 이용하여 해당 건물에 대한 위치를 추정하고, 3차원으로 기 모델링 된 건물을 증강현실 기법을 이용하여 영상에 정합한 후 가시화 한다.

• Transactions on Electrical and Electronic Materials
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• v.17 no.5
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• pp.306-309
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• 2016

The Cs₃Sb photocathode was formed by non-vacuum process technology. An in-situ vacuum device was fabricated successively with flat cesium antimonide photocathode emitters fabricated in a process chamber. The electrical properties of the device were characterized. Electron emission from the devices was induced by photoemitted electrons, which were accelerated by an anode electric field that was shielded from the photoemitter surface. The electrical characteristics of the devices were investigated by measuring the anode current as a function of device operation times with respect to applied anode voltages. Planar blue LED light with a 450 nm wavelength was used as an excitation source. The results showed that the cesium antimonide photocathode emitter has the potential of long lifetime with stable electron emission characteristics in panel devices. These features demonstrate that the cesium antimony photocathodes produced by non-vacuum processing technology is suitable for flat cathodes in panel device applications.

• Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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• v.25 no.3
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• pp.40-49
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• 2011

This paper presents novel circuit topology of half-bridge soft-switching PWM inverter type DC-DC high power converter for DC bus feeding power plants. The proposed DC-DC power converter is composed of a typical voltage source-fed, half-bridge high frequency PWM inverter with a high frequency planar transformer link PWM control scheme and parallel capacitive lossless snubbers. The operating principle of the new DC-DC converter treated here is described by using switching mode-equivalent circuits, together with its unique features. All the active power switches in the half-bridge arms and input DC bus lines can achieve ZCS turn-on and ZVS turn-off commutation transitions. The total turn-off switching losses of the power switches can be significantly reduced. As a result, high switching frequency IGBTs can actually be selected in the frequency range of 40[kHz] under the principle of soft-switching. The performance evaluations of the experimental setup are illustrated practically.