• Title/Summary/Keyword: Inclined Field

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Activation plans for e-logistics of information era (정보화시대의 e-물류 효율화방안)

  • Lee, Shin-Kyuo
    • The Journal of Information Technology
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    • v.7 no.1
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    • pp.87-104
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    • 2004
  • This study is to understand basic knowledge on e-logistics through the analysis of third party logistics(3PL) as well as fourth party logistics(4PL) and to suggest some activation plans of e-logistics of information era to get competition in the field of international logistics. Compared with advanced countries, Korean companies has not activated 3PL logistics as Korean companies are not inclined to open their business information to others and they didn't recognize the importance of logistics. As the business environments are worsening little by little, there has been greater concerns for e-logistics as a way of focusing on the core-business. Most of Korean companies has outsourced simple and limited scope of 3PL and 4PL services with 1st level of logistics outsourcing. To activate e-logistics, Korean government and private enterprises have to pursue the following strategies. First, Korean government should change the present laws preventing the enterprises specialized in 3PL from doing business and should pursue logistics information and standardization. Also the government needs to support 3PL companies. Second, private companies do their best to retain and develope factors of logistics resources professional and to develope the latest technology. 3PL providers have pursue effective logistics strategies and to invest capitals for the information technology.

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The Fuzzy Steering Control Using a Slope Direction Estimation Method for Small Unmanned Ground Vehicle (경사방향 추정 기법을 이용한 소형로봇의 퍼지 조향 제어)

  • Lee, Sang Hoon;Huh, Jin Wook;Kang, Sincheon;Lee, Myung Chun
    • Journal of the Korea Institute of Military Science and Technology
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    • v.15 no.6
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    • pp.721-728
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    • 2012
  • The tracked SUGVs(Small Unmanned Ground Vehicles) are frequently operated in the narrow slope such as stairs and trails. But due to the nature of the tracked vehicle which is steered using friction between the track and the ground and the limited field of view of driving cameras mounted on the lower position, it is not easy for SUGVs to trace narrow slopes. To properly trace inclined narrows, it is very important for SUGVs to keep it's heading direction to the slope. As a matter of factor, no roll value control of a SUGV can makes it's heading being located in the direction of the slope in general terrains. But, the problem is that we cannot directly control roll motion for SUGV. Instead we can control yaw motion. In this paper, a new slope driving method that enables the vehicle trace the narrow slopes with IMU sensor usually mounted in the SUGV is suggested which including an estimation technique of the desired yaw angle corresponding to zero roll angle. In addition, a fuzzy steering controller robust to changes in driving speed and the stair geometry is designed to simulate narrow slope driving with the suggested method. It is shown that the suggested method is quite effective through the simulation.

A Study on Rotational Alignment Algorithm for Improving Character Recognition (문자 인식 향상을 위한 회전 정렬 알고리즘에 관한 연구)

  • Jin, Go-Whan
    • Journal of the Korea Convergence Society
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    • v.10 no.11
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    • pp.79-84
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    • 2019
  • Video image based technology is being used in various fields with continuous development. The demand for vision system technology that analyzes and discriminates image objects acquired through cameras is rapidly increasing. Image processing is one of the core technologies of vision systems, and is used for defect inspection in the semiconductor manufacturing field, object recognition inspection such as the number of tire surfaces and symbols. In addition, research into license plate recognition is ongoing, and it is necessary to recognize objects quickly and accurately. In this paper, propose a recognition model through the rotational alignment of objects after checking the angle value of the tilt of the object in the input video image for the recognition of inclined objects such as numbers or symbols marked on the surface. The proposed model can perform object recognition of the rotationally sorted image after extracting the object region and calculating the angle of the object based on the contour algorithm. The proposed model extracts the object region based on the contour algorithm, calculates the angle of the object, and then performs object recognition on the rotationally aligned image. In future research, it is necessary to study template matching through machine learning.

Rockfall Behavior with Catchment Area Condition (포집공간 조건에 따른 낙석의 거동)

  • Lee, Jundae;Kwon, Youngcheul;Bae, Wooseok
    • Journal of the Korean GEO-environmental Society
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    • v.20 no.1
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    • pp.35-42
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    • 2019
  • Various development works inevitably increase cutting slopes due to land use, and many of trails managed by different authorities are being deteriorated by long-term weathering. Collapse of slopes causes unavoidable damage of property and loss of lives because of its uncertainty and difficulty in predicting its occurrence. In order to overcome the unavoidability, America, Japan, and several European nations analyze the kinetic energy and moving distance when rocks of upper slope move along the inclined plane, via field tests and computerized interpretation of the test results. Also, they are making efforts to develop measures with which the kinetic energy of the rocks moving along the slope is absorbed and fails to reach to specific structures. However, domestic researches just focus on fragmentary prediction of rockfall using existing programs, and there have been few approaches to identify interpretation methods appropriate for domestic cases or determination of parameters. In this context, we in this study defined rockfall types and affecting factors and analyzed effects of parameters using a general-purpose rockfall simulation program to understand principles of rockfall and to estimate effects of various parameters.

The physical properties of several HTS coated conductors

  • Lee, Nam-Jin;Oh, Sang-Soo;Song, Kyu-Jeong;Ha, Dong-Woo;Kim, Ho-Sup;Ha, Hong-Soo;Ko, Rock-Kil;Kim, Tae-Hyung;Kim, Sang-Cheol;Yu, Kwon-Kuk;Moon, Seung-Hyun;Youm, Do-Jun
    • Progress in Superconductivity and Cryogenics
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    • v.9 no.4
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    • pp.19-23
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    • 2007
  • The superconducting properties of several HTS coated conductors (CC), which had different tape structures, fabricated by KERI, X and Y institutes were compared. We have fabricated the $high-J_c$ SmBCO CC, which has 273.5 A/cm, $1.2MA/cm^2$ and 93.5 K for $I_C,\;J_C\;and\;T_{c-zero}$, respectively, using the EDDC (Evaporation using Drum in Dual Chambers) process. Both X and Y institutes CCs, however, were purchased. The n-values of KERI, X and Y institutes CCs are 58.5, 40.7 and 31.5 in $V=1{\sim}10{\mu}V$ criterion, respectively. The in-field properties of $I_C$ at 77K were investigated and the $J_C(B)/J_C(0G)$ at 0.5 T with $B{\perp}$ ab-plane are 0.31, 0.19 and 0.24 for KERI, X and Y institutes CCs, respectively. From the $I_C-{\theta}-B$ measurement, we observed that the ab-plane of ReBCO phase was tilted for the ab-plane of substrate in the KERI and X institutes CCs. The tilted angle is about 5 degree. We confirmed that the peak shift (as an inclined texture) was observed by X-ray (102) pole figures of the SmBCO for the KERI CC.

Electromagnetic Traveltime Tomography with Wavefield Transformation (파동장 변환을 이용한 전자탐사 주시 토모그래피)

  • Lee, Tae-Jong;Suh, Jung-Hee;Shin, Chang-Soo
    • Geophysics and Geophysical Exploration
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    • v.2 no.1
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    • pp.17-25
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    • 1999
  • A traveltime tomography has been carried out by transforming electromagnetic data in frequency domain to wave-like domain. The transform uniquely relates a field satisfying a diffusion equation to an integral of the corresponding wavefield. But direct transform of frequency domain magnetic fields to wave-field domain is ill-posed problem because the kernel of the integral transform is highly damped. In this study, instead of solving such an unstable problem, it is assumed that wave-fields in transformed domain can be approximated by sum of ray series. And for further simplicity, reflection and refraction energy compared to that of direct wave is weak enough to be neglected. Then first arrival can be approximated by calculating the traveltime of direct wave only. But these assumptions are valid when the conductivity contrast between background medium and the target anomalous body is low enough. So this approach can only be applied to the models with low conductivity contrast. To verify the algorithm, traveltime calculated by this approach was compared to that of direct transform method and exact traveltime, calculated analytically, for homogeneous whole space. The error in first arrival picked by this study was less than that of direct transformation method, especially when the number of frequency samples is less than 10, or when the data are noisy. Layered earth model with varying conductivity contrasts and inclined dyke model have been successfully imaged by applying nonlinear traveltime tomography in 30 iterations within three CPU minutes on a IBM Pentium Pro 200 MHz.

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The Dosimetric Effects on Scallop Penumbra from Multi-leaf Collimator by Daily Patient Setup Error in Radiation Therapy with Photon (광자선 치료시 Setup 오차에 따르는 Multi-leaf Collimator의 Scallop Penumbra 변화 효과)

  • Yi, Byong-Yong;Cho, Young-Kap;Chang, Hye-Sook
    • Radiation Oncology Journal
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    • v.14 no.4
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    • pp.333-338
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    • 1996
  • Purpose : To evaluate the clinical implications of scallop penumbra width that comes from multileaf collimator(MLC) effect by the daily routine patient setup error. Materials and Methods : The anales of $0^{circ},{\;}15^{circ},{\;}30^{circ},{\;}45^{circ},{\;}60^{circ},{\;}and{\;}75^{circ}$ inclined -radiation blocked fields were generated using the both conventional cerrobend block and the MLC. Film dosimetry in the phantom were performed to measure penumbral widths of differences between the dose distributions from the cerrobend block and those of respect the MLC. The patient setup error effect on scallop penumbra was simulated with respect to the table of setup error distribution. Same procedures are repeated for the cerrobend block generated field. Results : There are penumbral widths of to 3mm difference between the dose distributioins from two kinds of field shaping tools, the conventional block and the MLC with 4mm setup error model and resolution of 1cm leaf at the isocenter. Conclusion : We need not additive margin for MLC, if planning target volume is selected according to the recommendation of ICRU 50. For particular cases, we can include the target volume with less than 3mm additive margin.

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Magnetotelluric survey applied to geothermal exploration: An example at Seokmo Island, Korea (자기지전류법을 이용한 석모도에서의 지열자원 탐사)

  • Lee, Tae-Jong;Han, Nu-Ree;Song, Yoon-Ho
    • Geophysics and Geophysical Exploration
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    • v.13 no.1
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    • pp.61-68
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    • 2010
  • A magnetotelluric (MT) survey has been performed to delineate deeply extended fracture systems at the geothermal field in Seokmo Island, Korea. To assist interpretation of the MT data, geological surveying and well logging of existing wells were also performed. The surface geology of the island shows Cretaceous and Jurassic granite in the north and Precambrian schist in the south. The geothermal regime has been found along the boundary between the schist and Cretaceous granite. Because of the deep circulation along the fracture system, geothermal gradient of the target area exceeds $45^{\circ}C/km$, which is much higher than the average geothermal gradient in Korea. 2D and 3D inversions of MT data clearly showed a very conductive anomaly, which is interpreted as a fracture system bearing saline water that extends at least down to 1.5 km depth and is inclined eastwards. After drilling down to the depth of 1280 m, more than 4000 tons/day of geothermal water overflowed with temperature higher than $70^{\circ}C$. This water showed very similar chemical composition and temperature to those from another existing well, so that they can be considered to have the same origin; i.e. from the same fracture system. A new geothermal project for combined heat and power generation was launched in 2009 in Seokmo Island, based on the survey. Additional geophysical investigations including MT surveys to cover a wider area, seismic reflection surveys, borehole surveys, and well logging of more than 20 existing boreholes will be conducted.

Effects of antimony addition on growth of InGaN nano-structures by mixed-source HVPE (혼합소스 HVPE 방법에 의한 InGaN 나노구조의 성장에 있어서 Sb 첨가의 영향)

  • Ok, Jin-Eun;Jo, Dong-Wan;Jeon, Hun-Soo;Lee, Ah-Reum;Lee, Gang-Suok;Cho, Young-Ji;Kim, Kyung-Hwa;Chang, Ji-Ho;Ahn, Hyung-Soo;Yang, Min
    • Journal of the Korean Crystal Growth and Crystal Technology
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    • v.20 no.3
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    • pp.113-116
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    • 2010
  • We report on the growth and characteristics of the structural and optical properties of InGaN nano-structures doped with antimony (Sb) as a catalyst. The use of catalyst has been explored to modify the growth and defect generation during strained layer heteroepitaxial growth. We performed the growth of the InGaN nano-structures on c-sapphire substrates using mixed-source hydride vapor phase epitaxy (HVPE). The characteristic of samples was measured by scanning electron microscope (SEM) and photoluminescence (PL). The aligning direction of c-axis of the InGaN nano-structures was changed from vertical to parallel or inclined to the surface of substrates when the Sb was added as a catalyst. The indium composition was estimated about 3.2% in both cases of with or without the addition of Sb in the InxGal-xN structures. From the results of InGaN nano-structures formed with the addition of Sb, we can expect the performance of optical devices would be more improved by reduced piezo-electric field if we use the InGaN nano-structures of which c-axes are aligned parallel to the substrates as an active layer.

Presown Seed Treatments to Promote Seed Germination of Zoysiagrass (Zoysia japonica) (한국잔디 종자의 발아율 향상을 위한 파종전 종자처리)

  • 전병삼;강진호;조상철;권혁식;류영섭
    • Korean Journal of Plant Resources
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    • v.14 no.2
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    • pp.175-181
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    • 2001
  • Dormancy of intact zoysiagrass seeds hinders its seed propagation in which presowing seed treatment must be done to overcome it. The study was done to remodel the presowing treatments of zoysiagrass seeds by determining the treatment effects of seedcoat softening, prechilling, drying and combined light treatment with them or during germination stage. Seedcoat softening with different chemicals (NaOH 20%, KOH 20%, $H_2SO_4\;8M, acetone 20%) and periods (10, 30, 60 min.), prechilling with different periods at 3$^{\circ}C$, and drying with 4 hours at 35$^{\circ}C$ was done. Light sources were also applied with 660 nm red LED light, commercial fluorescent and incandescent light and darkness. Germination test was done in alternative day and night temperature of 35 and 2$0^{\circ}C$ to check the daily germination rates. With seeds treated with NaOH 20% for 30 minutes, red and incandescent light showing similar responses inclined their germination rates compared to dark conditions. Drying resulted in its higher rate than non-drying but fluorescent light treatment forced during drying more enhanced the rate than red light. While mean germination rate considering all the seedcoat softening treatment periods was the greatest in $H_2SO_4$ in comparison with NaOH, KOH and acetone, NaOH treatment for 30 minutes showed the best rate among the all the treatment levels. In the conditions of sowing them to no-mulching field, presowing treatment procedure of zoysiagrass seeds was remodeled: the seedcoat softening treatment with NaOH 20% for 30 minutes was done, washed, and chilled at 3$^{\circ}C$ for 2 weeks before dried under 4 hour fluorescent light illumination at 35$^{\circ}C$.

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