• Journal of the Korean Geotechnical Society
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• v.15 no.3
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• pp.113-129
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• 1999

In this study, a total of 12 types of sequential model tests were conducted at the laboratory for small scale anchored walls. The sequential behavior for flexible wall embedded in sand was investigated by varying degrees of relative density of Joomoonjin sand and flexibility number of model wall. The model tests were carried out in a 1000mm width, 1500mm length, and 1000mm high steel box. Load cells, pressure cells, displacement transducer and dial gauges were used to measure the anchor forces, lateral wall deflections, lateral earth pressures and vertical displacements of ground surface, respectively. Limited model tests were performed to examine the parameters for soil-wall interaction model and the formulation of analytical method was revised in order to predict the behavior of anchored wall in sand. Based on the model tests and proposed analytical method, model simulations were performed and the predictions by the present approach were compared with measurements by the model tests and predictions by other commercial programs. It is shown that the prediction by the present approach simulates qualitatively well the general trend observed for model test.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2002.05a
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• pp.197-200
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• 2002

The current Inn technique is many problems that is permission of radio station using RF Wireless Modem, that is influence of geographic obstacle using radio wave, that is frequency interference, that is finiteness of frequency resources. In this paper, we are solved many elements, IM replaces RF Wireless Modem, we suggest transmission technique of correction message using mobile phone, we researched Interface Module development which is linkage of DGPS receiver and mobile phone. IM can transmit correction message passing RS-232 port and modem communication control. IM of base station is initialized RS-232 port and modem to move station for correction message transmission, IM waited response mode. IM of move station is initialized RS-232 port and modem, IM requests hand shaking to base station, completed connection establishment. Users are worked Differential surveying using receiving correction message between mobile phones.

• Journal of the Korean Chemical Society
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• v.55 no.2
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• pp.183-188
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• 2011

The electronic structure and properties of Ni$(C_6H_{4-n}F_n)(CO)_2$ ($C_6H_4$=benzyne, n=1-4) complexes have been investigated using hybrid density functional B3LYP theory. Both aromatic natures and nucleus independent chemical shift (NICS) of the benzyne rings have been analyzed. Among mono-, di-, and tri-fluorinated complexes, 3-F, 3,6-F, and 4-H are the most stable isomers, respectively. NICS values calculated at the several points above the ring centers are consistent with those based on the relative energies of the complexes. The atoms in molecules (AIM) analysis indicates that Ni-C bond distance is well correlated with the electron density of a ring critical point (${\rho}_{rcp}$) in all species.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.26 no.11A
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• pp.1938-1945
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• 2001

In this paper, a new scheme for image conversion of the 2D input images into the stereoscopic 3D images by using differential shifting method is proposed. First, the relative depth information is estimated by disparity and occlusion information from the input stereo images and then, each of image objects are segmented by gray-level using the estimated information. Finally, through the differential shifting of the segmented objects according to the horizontal parallax, a stereoscopic 3D image having optimal stereopsis is reconstructed. From some experimental results, it is found that the horizontal disparity can be improved about 1.6dB in PSNR for the reconstructed stereo image using the proposed scheme through comparing to that of the given input image. In the experiment of using the commercial stereo viewer, the reconstructed stereoscopic 3D images, in which each of the segmented objects are horizontally shifted in the range of 4 ∼5 pixels are also found to have the mast improved stereopsis.

• The Journal of Korea Institute of Information, Electronics, and Communication Technology
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• v.13 no.5
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• pp.377-388
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• 2020

In this paper, the autonomous mobile robot whit only LRF sensors proposes an algorithm for avoiding moving obstacles in an environment where a global map containing fixed obstacles. First of all, in oder to avoid moving obstacles, moving obstacles are extracted using LRF distance sensor data and a global map. An ellipse-shaped safety radius is created using the sum of relative vector components between the extracted moving obstacles and of the autonomuos mobile robot. Considering the created safety radius, the autonomous mobile robot can avoid moving obstacles and reach the destination. To verify the proposed algorithm, use quantitative analysis methods to compare and analyze with existing algorithms. The analysis method compares the length and run time of the proposed algorithm with the length of the path of the existing algorithm based on the absence of a moving obstacle. The proposed algorithm can be avoided by taking into account the relative speed and direction of the moving obstacle, so both the route and the driving time show higher performance than the existing algorithm.

• Journal of Navigation and Port Research
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• v.33 no.1
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• pp.1-7
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• 2009

Navigation speed control is an important factor to improve the traffic safety, it is only researched about maximum speed control until now. Recently, there are lots of the low speed vessels including towing boats, carry heavy shipbuilding blocks in the Korean waters, so the danger degree of navigating vessels was increasing more and more. This paper analysed the effectiveness of minimum speed control with the operation burden's decrease, and it proposed the proper the minimum navigation speed of each traffic volume. Main results of this research are as follows. (1) in the case of 5 ships/hour, minimum speed control is effective if the lowest speed is fixed more than 5kts. (2) in the case of more than 10 ships/hour, speed control is some effective if the lowest speed is established 7kts. (3) But, when there are many ships in the waters, minimum speed control is not effective because distances between ships become near and ships navigate for a long time by a lot of ship having a few difference of relative speed.

• Journal of Navigation and Port Research
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• v.33 no.1
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• pp.21-25
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• 2009

The ship without thrusters and special propulsion system is supported by the tug boats during berthing and unberthing. The orders to tug boats are made by a pilot. If the positions of ship, tug boats and port are displayed in 2D map, it will be helpful to pilots. In this research, a network-based pilot supporting system(NPSS) has been conceptually designed NPSS, necessary for safe and efficient pilot, has two main functions. One is the monitoring of the situation of berthing and unberthing. And the other is the automatic calculation of the tug forces considering environmental conditions. The NPSS is designed on the basis of network system around the harbor. The NPSS will be validated using ship-handling simulator in the future.

• Journal of KIISE:Computing Practices and Letters
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• v.13 no.4
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• pp.226-230
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• 2007

In the conventional desktop PC environment, keyboard and mouse are used to process the user input and monitor displays the visual information as an output device. In order to manipulate the digital information, we move the virtual cursor to select the desired graphical icon on the monitor The cursor represents the relative motion of the physical mouse on the desk. This desktop metaphor does not provide intuitive interface through human sensation. In this paper, we introduce a novel tangible interface which allows the user to interact with computers using a physical tool called "Smartpuck". SmartPuck system bridges the gap between analog perception and response in human being and digital information on the computer. The system consists of table display based on a PDP, SmartPuck equipped with rotational part and button for the user's intuitive and tactile input, and a sensing system to track the position of SmartPuck. Finally, we will show examples working with the system.

• Proceedings of the Korea Water Resources Association Conference
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• 2012.05a
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• pp.612-612
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• 2012

최근 GIS를 이용하여 수리 수문학적인 지형인자를 생성할 수 있는 Arc Hydro 등의 다양한 GIS 기반 툴들이 개발되어 왔다. 예를 들어 Arc Hydro는 격자형 고도자료인 수치표고모델(Digital Elevation Model)을 통해 수자원에서 필요로 하는 유로연장, 유역경사 등의 지형인자를 산정할 수 있는 기능을 제공해 주고 있다. 하지만 기존의 GIS 기반 툴에서는 Manning의 평균유속 공식 등 하천수리학에서 매우 중요한 인자인 하천경사를 하천망을 따라 산정하고 표출하는 기능이 부족하였다. 또한 하천경사 산정에 사용되는 여러 GIS 툴을 통해서 제공되는 셀 경사 등 지형인자들의 기계적인 적용으로 정확한 하천경사의 산정에 문제가 있어왔다. 본 논문은 이러한 지형인자들의 적용성을 평가하고 다양한 이론적 하천경사 산정법을 GIS 상에 적용하여 상호 비교하여 최적화된 하천경사 산정방법을 제시하고자 한다. 연구 대상유역으로는 제주도를 선정하였으며, 대상 하천은 Arc Hydro를 이용하여 산정된 하천망의 형태를 수자원관리정보시스템(WAMIS), 위성사진 등과 비교한 후 시범 하천(한천)을 선택하여 여러 하천경사 산정법을 적용해 보았다. 적용된 산정법은 총 4가지로 첫 번째 방법은 수치표고모델의 주변 표고를 고려하여 산정된 기울기를 Arc Hydro를 이용하여 산정된 하천을 따라 산술평균하는 방법이며, 나머지 3가지 방법은 하천망을 따라 흐름방향의 거리와 수치표고모델의 표고를 수집한 후에 단순경사방법, 등면적경사방법, 등가경사방법에 적용하는 방법이다. 산정된 하천경사를 상대비교를 하여 대상유역에 대한 비교검토를 실시하였다. 모든 과정은 프로그램 개발을 통해 자동화 시켜 향후 다른 유역의 적용과 변화 가능한 지형정보를 신속하고 효율적인 예측을 가능할 수 있도록 하였다. 또한 주어진 하천망의 두 지점 사이의 종방향 경사를 산정하여 표출하는 기능을 추가하여 하천 경사의 표출방식을 향상시켰다. GIS를 이용하여 산정되어진 하천경사의 적용성이 충분하다면 Manning의 평균유속 공식에 적용할 수 있을 뿐만 아니라 다양한 하천분석이 용이해 질 것으로 예상된다.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.38 no.12
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• pp.957-962
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• 2014

We present a method to quantitatively measure the thermal conductivity of one-dimensional nanostructures by utilizing scanning thermal wave microscopy (STWM) at a nanoscale spatial resolution. In this paper, we explain the principle for measuring the thermal diffusivity of one-dimensional nanostructures using STWM and the theoretical analysis procedure for quantifying the thermal diffusivity. The SWTM measurement method obtains the thermal conductivity by measuring the thermal diffusivity, which has only a phase lag relative to the distance corresponding to the transferred thermal wave. It is not affected by the thermal contact resistances between the heat source and nanostructure and between the nanostructure and probe. Thus, the heat flux applied to the nanostructure is accurately obtained. The proposed method provides a very simple and quantitative measurement relative to conventional measurement techniques.