• Electronics and Telecommunications Trends
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• v.29 no.6
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• pp.113-125
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• 2014

최근 모바일 단말 기술의 발전과 무선망의 성능 향상에 따른 다양한 서비스가 제공되고 있는 추세이며, 위치정보인식시스템과 결합된 서비스에 많은 관심이 높아졌다. 본고에서는 GPS(Global Positioning System)의 신호가 미치지 못하는 건물의 실내환경에 적합한 경로 안내서비스 및 지하시설물 안내 등 초정밀 실내 측위 서비스를 제공하기 위한 융합 측위 방안을 제안한다. 융합 측위 방안은 실내외 연속 측위를 위해 실외에서는 GPS를 이용하고 실내환경에서는 WLAN 기반의 측위 전용 AP(Access Point)를 이용, 전파신호의 LoS(Line of Sight)를 확보하여 측위하고 전파음영지역에서는 스마트폰의 가속도, 자이로센서 등 여러 가지 관성센서를 활용하여 PDR(Pedestrian Dead Reckoning) 알고리즘 등을 적용하여 측위한다. 또한 측위 정확도 향상 및 오차를 줄이기 위한 방법으로 LSE(Least Squire Estimation) 및 EKF(Extended Kalman Filter), KNN(K-Neighbor Node)/MSSM(Maximum Signal Strength Model) Algorithm 등 다양한 융합 측위 알고리즘을 적용하여 실내환경에 적합한 최적의 초정밀 실내 측위 서비스를 제공한다.

• Journal of Institute of Control, Robotics and Systems
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• v.18 no.11
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• pp.1011-1017
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• 2012

Augmented Reality is being widely used not only for Smartphone users but also in industries such as maintenance, construction area. With smartphone, due to the low localization accuracy and the requirement of special infrastructure, current LBS (Localization Based Service) is limited to show P.O.I. (Point of Interest) nearby. Improvement of IMU (Inertial Measurement Unit) based deadreckoning is presented in this paper. Additional sensors such as the magnetic compass and magnetic flux sensors are used as well as the accelerometer and the gyro for getting more movement information. Based on the pedestrian movement, appropriate sensor information is selected and the complementary filter is used in order to enhance the accuracy of the localization. Additional sensors are used to measure the movements of the upper body and the head and to provide the user's line of sight.

• Journal of Ecology and Environment
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• v.35 no.3
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• pp.189-194
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• 2012

Coarse woody debris (CWD) is generally considered dead woody material in various stages of forest decomposition and has been hypothesized to be an important habitat feature for mammals in forests of the Pacific Northwest, USA. Sherman and pitfall trapping were conducted for 2 years on three paired sites with low and high amounts of CWD. Deer mice was the dominant species with a total capture of 605 (45.6%). Four species of insectivores were captured, including Sorex moncicolus, S. trowbridgii, S. vagrans, and Neurotrichus gibbsii. A Poisson regression model was used to test whether 11 CWD variables could predict insectivore captures. The volume of logs and mean decay were important variables for deer mice use of CWD. Mean distance from pieces of CWD to the capture point was significantly related to the total number of captures of trowbridge shrew (Sorex trowbridgii) and all insectivore species. Vagrant shrews (Sorex vagrans) were significantly associated with log volume. Retaining large size CWD should be part of a management plan for ground-dwelling insectivores in forests to secure their biodiversity.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 1996.04a
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• pp.313-318
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• 1996

This paper deals with the dynamic behavior of elastic columns under the action of subtangential forces. The above subtangential force can be-realized by the combination force between the dead load of thetip mass and the pure follower thrust. The tip mass is assumed to be a rigid body not a mass point as it has been assumed so for. The equations of motion are formulated based on extended Hamilton's principle and the finite element method. It is shown that nonconservativeness of the applied force has greatly effect on the instability type. It is found that the critical subtangential force can also be changed by consideration of the tip mass parameters taking into account of its magnitude, rotary inertia and size. The influence of the self-weight of the column on the change of the critical force is also investigated.

• Journal of Institute of Control, Robotics and Systems
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• v.8 no.6
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• pp.439-444
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• 2002

In this paper, a new model reduction method is proposed to obtain a reduced order model in the frequency domain. The method is developed based on the second-order plus dead time modeling technique. The initial value of the reduced model parameters can be obtained using this method coinciding four point(0, -$\pi$/2, -$\pi$, -3$\pi$/2) on the Nyquist curve. The optimal parameters of the reduced model is obtained through calculation procedure with three steps. It is shown that Nyquist curves and unit step responses of the reduced models of numerical examples closely agree with those of original models.

• The Research Journal of the Costume Culture
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• v.9 no.1
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• pp.154-168
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• 2001

This study is intended to understand an implication and significant of anti-design and Italian radical fashion. Anti-design and radicalism is the main stream or origin and essence of post-modernism which hs been swaying our society at large through modern culture, economy, art, fashion etc, from the latter part of 1960s. In this paper, the author classified the italian radical fashion with the Archizoom, the Alchymia, the memphis fashion. In post-modernism fashion, radical fashion design of the Archizoom, Alchymia and Memphis group is in part a menifesto and in part a noncanonical history of the most progressive and heretical experiments of the world of fashion. Anti-designers of Italy call for a theory an practive in which the old methods and instruments and the old commendments of modernism are banished. They looked on fashion as material culture, a creative field with its own independent foundation and endowed with its own strong artistic intuition. IF radical design is dead, the energy it has stirred up is still alive nd kicking. One of the most progressive and well-informed culture milieus in Milian, seved as a point of reference for the vanguard of fashion.

• Transactions of the Korean Society of Mechanical Engineers
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• v.18 no.2
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• pp.502-511
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• 1994

A video deck mechanism is composed of various cams, links, and gears, and it requires precise movement. So kinematic motion between parts should be considered to get desired movement depending on the timing chart which defines movement of each part to get desired mode. Also dynamic effects should be considered to get right tape tension and to estimate motor force required to obtain accurate motion. The design process of the deck mechanism of VCR is explained briefly. The loading block of the deck mechanism is divided into a tape translational group and a brake control group. Each group is modeled for kinematic and dynamic analysis. Finally, two groups are combined together to analyze the loading block of the deck mechanism. Results are used to understand and modify an existing design.

• Toxicological Research
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• v.17 no.4
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• pp.287-296
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• 2001

The acute oral LD5O toxicity values of isazofos, pyraclofos, diazinon and methomyl were determined for Japanese quail based on OECD guideline. The $LD_{50}$ of isazofos, pyraclofos and diazinon was 16.26 mg/kg, and 7.11mg/kg body weight In female respectively. And the $LD_{50}$ of each chemical in male was 21.44, 35.64, 8.28 mg/kg body weight respectively. Diazinon was the most susceptible compounds to Japanese quail in both sexes. The $LD_{50}$ of methomyl was 21.24 mg/kg body weights in female, and 28.28 mg/kg body weight in male respectively. Diazinon, isazofos and methomyl were more toxic In the female than male. The symptoms of poisoning were similar in quails administrated with each chemicals. The clinical sign in Japanese quail were ataxia, salivation, diarrhea, ruffled feather and convulsion at dead point. There were severe hemorrhage and catarrhal inflammation from duodenum to ileum In all compounds. In Japanese quail treated with organophosphorus and carbamate compounds, brain acetylcholinesterase was inhibited by 88-96. The recovery was not observed after 5 h in sublethal dose.

• Journal of the Korean Society of Industry Convergence
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• v.17 no.3
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• pp.113-121
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• 2014

This paper presents a optimization design of 10[W] single phase BLDC motor applied Notch shape. Cogging Torque causes noise, vibration and torque ripple so notched stator is proposed in this paper. Firstly, a single phase BLDC motor needs applying aymmetric air-gap shape because this type motor cannot help having dead-point which is zero torque position. However, using asymmetric air-gap structure causes cogging torque increase. Therefore, this paper proposes the notch shape structure. Notch shape structure has some advantages; low cost, easy to apply. There are 4 optimal factors selected in optimization process, which are position and size of notches. Through building a prototype, the result of FE analysis and the experimental measurement value are compared each other and then vailidity and utility of simulation will be verified.

• Journal of Magnetics
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• v.18 no.2
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• pp.117-124
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• 2013

Single-phase, brushless DC (BLDC) motors have unequal air-gaps to eliminate the dead-point where the developed torque is zero. Unfortunately, these unequal air-gaps can deteriorate the motor characteristics in the cogging torque. This paper proposes a novel design for a single-phase BLDC motor with an asymmetric notch to solve this problem. In the design method, the asymmetric notches were placed on the stator pole face, which affects the change in permanent magnet shape or the residual flux density of the permanent magnet. Parametric analysis was performed to determine the optimal size and position of the asymmetric notch to reduce the cogging torque. Finite element analysis (FEA) was used to calculate the cogging torque. A more than 28% lower cogging torque compared to the initial model with no notch was achieved.