• Title/Summary/Keyword: Directional Difference

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The Role of Political Ideology in the 2012 Korean Presidential Election: Evidence from Panel Data Analysis (제18대 대통령 선거에서 이념의 영향: 패널 데이터 분석 결과)

  • Kim, Sung-Youn
    • Korean Journal of Legislative Studies
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    • v.23 no.2
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    • pp.147-177
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    • 2017
  • Although a number of empirical studies found that political ideology plays a significant role in Korean elections, they entirely rely on cross-sectional data analysis. In contrast to previous research, this study investigates the effects of ideology in the 2012 Korean presidential election through standard panel data analysis. Specifically, using "EAI Panel Study, 2012", the effects of ideology on both candidate evaluation and vote choice were examined via fixed effects, random effects, and pooled regression analysis. And the results from applying the two most popular models of ideological voting, the proximity model and the directional change model were also compared. The results show that candidate evaluations and vote choice during the election (April, 2012- December, 2012) were significantly influenced by the ideological difference between voters and candidates, independent from partisanship and other standard socio-demographic factors. And this ideological voting during the election seems better captured by the directional change model than by the proximity model.

Characteristics of Physical Properties of Rocks and Their Mutual Relations (암석의 종류와 방향에 따른 물리적 특성과 상호관계)

  • 원연호;강추원;김종인;박현식
    • Tunnel and Underground Space
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    • v.14 no.4
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    • pp.261-268
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    • 2004
  • The main objectives of this study are to investigate the anisotropic characteristics of rocks and to evaluate the relationships between physical properties. A series of experiments were performed in three mutually perpendicular directions for three rock types, which are granite, granitic gneiss and limestone. The relationships of measured physical properties were evaluated. The results of ultrasonic wave velocity measurement show that granite of three rock types gives the largest directional difference, and that the wave velocity in a plane parallel to a transversely isotropic one is dominantly faster than that in a subvertical or vertical plane. It implies that ultrasonic wave velocity for rock could be used as a useful tool for estimating the degree of anisotropy. The ratio of uniaxial compressive strength to Brazilian tensile strength ranges approximately from 13 to 16 for granite. from 8 to 9 for granite gneiss, and from 9 to 18 for limestone. The directional differences for granite and granitic gneiss are very small, and on the other hand, is relatively large for limestone. It is suggested that strength of rock makes quite difference depending on the rock types and loading directions, especially for the anisotropic rocks such as transversely isotropic or orthotropic rocks. The ratio of uniaxial compressive strength to point load strength index ranges from 18 to 20 for granite, from 17 to 19 for granitic gneiss, and from 21 to 24 for limestone. These results show that point load strength index makes also a difference depending on rock types and directions. Therefore. it should be noted that the ratio of uniaxial compressive strength to point load strength index could be applied to all rock types. Uniaxial compressive strength shows relatively good relationship with point load strength index, Schmidt hammer rebound value, and tensile strength. In particulat, point load strength index is shown to be the best comparative relationship. It is indicated that point load test is the most useful tool to estimate an uniaxial compressive strength indirectly.

A Study on the Design of the Directional Coupler using Three Layer Microstrip Substrate (세 층 마이크로스트립 유전체 기판을 이용한 방향성 결합기 설계에 관한 연구)

  • 천동완;김원기;박정훈;김상태;신철재
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.12 no.4
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    • pp.513-520
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    • 2001
  • In this paper, the directional coupler using three layer microstrip substrate is proposed and the design method is notified. Modified re-entrant mode coupler is the proposed structure that one layer is added on upper plane of coupled transmission lines and the floating conductor is placed on added layer's upper planes. This structure has high coupling for the increase of odd mode capacitance and also has good performance in VSWR, isolation, phase difference because the difference of effective permittivity is small in each mode. We have designed the coupler from the calculation of impedance, effective permittivity, coupling coefficient using even, odd mode analysis method. From the simulation and measurement, proposed coupler has about 2 dB more tighter coupling than conventional coupler and also has good performance in VSWR, isolation, phase difference.

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A Study on Digital Communication in Air Using Parametric Array (파라메트릭 어레이를 이용한 공기 중 디지털 통신 연구)

  • Je, Yub;Lee, Jae-Il;Lee, Chong-Hyun;Moon, Won-Kyu
    • The Journal of the Acoustical Society of Korea
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    • v.28 no.8
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    • pp.768-773
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    • 2009
  • This paper demonstrates the digital communication in air using the parametric array. The stepped-plate transducer which is suitable for high-power and high-efficient radiation is used to generate the difference frequency wave with the parametric array. The primary frequencies are selected to 83 kHz and 122 kHz and the resulting difference frequency wave at the frequency of 39 kHz is used for the communication. The modulation method is selected to On-Off Keying method. The waveform and signal-to-noise ratio (SNR) is measured and analyzed to see the characteristics of the digital communication using the parametric array. The proper distance for the communication using parametric array is about 3 m. The measured beam width of the 3dB SNR reduction was $14^{\circ}$. The possibility of the communication in air using the parametric array is confirmed and the high directional characteristic of the communication using the parametric array is expected to have the advantages for the multi path and the security problems.

Design of GPS Receiving Antenna Installed in a Missile's Warhead (미사일 탑재형 GPS 안테나 설계)

  • Lee Jong-Min;Woo Jong-Myung
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
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    • v.17 no.9 s.112
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    • pp.900-912
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    • 2006
  • A GPS receiving antenna installed in the missile's warhead is designed and fabricated at a center frequency 1.575 GHz. The circular shaped antenna is installed in the middle of the warhead where the antenna's patch and the ground plane are connected with a hollow cylindrical shaped short pin. Using the dual feeding and phase difference method, an omni-directional radiation pattern which direction is normal to the missile's axis(H-plane) is obtained. The optimized diameters of the circular patch and the cylindrical ring typed shorting pin of the GPS receiving antenna which use the FR4.material(dielectric constant $\varepsilon_r=4.6$) are 59.5 mm and 14 mm, respectively. The cylindrical body with diameter 100 mm and height 500 mm is attached to the lower part of the warhead in order to complete the missile figure. The radiation patterns are measured by changing the angle and phase between the dual feeding points. When the phase difference of dual feeding is $100^{\circ}$ and the angle between the dual feeding points is $100^{\circ}$, the nearly omni-directional radiation pattern in the H-plane is obtained. In this case, the antenna gain is -5.55 dBd and the relative level difference between the maximum and the minimum radiation intensity is 3.98 dB.

Salient Object Extraction from Video Sequences using Contrast Map and Motion Information (대비 지도와 움직임 정보를 이용한 동영상으로부터 중요 객체 추출)

  • Kwak, Soo-Yeong;Ko, Byoung-Chul;Byun, Hye-Ran
    • Journal of KIISE:Software and Applications
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    • v.32 no.11
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    • pp.1121-1135
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    • 2005
  • This paper proposes a moving object extraction method using the contrast map and salient points. In order to make the contrast map, we generate three-feature maps such as luminance map, color map and directional map and extract salient points from an image. By using these features, we can decide the Attention Window(AW) location easily The purpose of the AW is to remove the useless regions in the image such as background as well as to reduce the amount of image processing. To create the exact location and flexible size of the AW, we use motion feature instead of pre-assumptions or heuristic parameters. After determining of the AW, we find the difference of edge to inner area from the AW. Then, we can extract horizontal candidate region and vortical candidate region. After finding both horizontal and vertical candidates, intersection regions through logical AND operation are further processed by morphological operations. The proposed algorithm has been applied to many video sequences which have static background like surveillance type of video sequences. The moving object was quite well segmented with accurate boundaries.

Numerical Analysis of Flow around Rectangular Cylinders with Various Side Ratios

  • Rokugou Akira;Okajima Atsushi;Kamiyama Kohji
    • 한국전산유체공학회:학술대회논문집
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    • 2003.10a
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    • pp.36-37
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    • 2003
  • Three-dimensional numerical analysis of the flow around rectangular cylinders with various side ratios, D/H, from 0.2 to 2.0 is carried out for Reynolds number of 1000 by using multi-directional finite difference method in multi-grid. The predicted results are well compared with the experimental data. It is found that fluid dynamics characteristics alternate between high pressure mode. and low pressure mode of the base pressure for rectangular cylinder of D/H=0.2-0.6.

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Comparison of the fatigue limit of fiber-reinforced composites and stainless steel wires when attached to the tooth surface for anchorage reinforcement (고정원 강화를 위해 치면에 부착한 fiber-reinforced composite과 스테인리스강 와이어의 피로한도 비교)

  • Kim, Moon-Jung;Park, Soo-Byung
    • The korean journal of orthodontics
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    • v.35 no.4 s.111
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    • pp.302-311
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    • 2005
  • This study was performed to compare the fatigue limit of stainless steel wires and Fiber-reinforced composites (FRC) under conditions of permitting physiologic tooth movement. and to evaluate the clinical value of FRCs which was used to reinforce the anchorage unit. The stainless steel wire groups were divided into round and rectangular wire groups. The FRC groups were divided into uni-directional and woven groups, with resin coating and without resin coating in the Proximal area After the number of cycles to failure of each of the 6 groups were measured within the $5{\times}10^5\;cycle$ fatigue limit simulating the orthodontic treatment period. the fatigue limit of each group was compared with each other The findings of this study were as follows. In stainless steel wires, the fatigue limit of rectangular wires were higher than that of round wires. But there was no statistically significant difference (p>0.05). In FRCs with resin coating and without resin coating in the interproximal area, the fatigue limit of uni-directional type was higher than that of the woven type (p<0.05). In uni-directional and woven type FRCs, the fatigue limit of FRC with resin coating in the interproximal area was higher thar that of FRC without resin coating (P<0.05) As the FRCs and stainless steel wires did not fracture until the $5{\times}10^5\;cycle$ fatigue limit which clinically is useful. it is sufficient to use FRC and stainless steel wire for reinforcing anchorage. When esthetics is important and the attachment of additional devices are necessary. it seems sufficient to use FRC as anchorage reinforcement.

Analytical Study on the Appropriateness of Design Formula and Possibility of Improving Bearing Capacity of Bored Pile (매입말뚝의 설계식 적정성 및 지지력 상향 가능성 분석 연구)

  • Park, Jong-Bae;Lee, Bum-Sik;Park, Yong-Boo
    • Land and Housing Review
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    • v.6 no.3
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    • pp.139-145
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    • 2015
  • To improve the pile design efficiency(design bearing capacity/the strength of materials) from 70 percent(160tonf) to 80 percent(190tonf), this paper analysed the existing pile loading test data and performed the precise dynamic loading test and Bi-directional loading test for the first time in Korea. Analysis result of the existing dynamic loading test data by Davisson method showed that bearing capacity of piles penetrated at weathered rock stratum(N=50/15) exceeded 190tonf. But the analysis result by CAPWAP method showed that piles less than the target bearing capacity were 40% due to the lack of impact energy. To get the target bearing capacity from the dynamic loading test, using the hammer over 6tonf to trigger the enough impact energy is necessary. Allowable bearing capacty of Bi-directional static loading test by Davisson method was 260.0~335tonf(ave. 285.3tonf) and exceeded overwhelmingly the target capacity. And this exceeded the bearing capacity of precise dynamic loading test(ave. 202.3tonf) performed on the same piles over 40%. The difference between the capacity of Bi-directional loading test and dynamic loading test was caused by the insufficient impact energy during dynamic loading test and increase by interlocking effect by near piles during Bi-directional static loading test.

Effects of Woman's Ability Balance High heels According to the Supporting Surface Balance Training (지지면에 따른 균형훈련이 하이힐을 신은 여성의 균형능력에 미치는 영향)

  • Hwang, Jinuk;Bae, Wonsik
    • Journal of The Korean Society of Integrative Medicine
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    • v.1 no.2
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    • pp.93-104
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    • 2013
  • Purpose : The purpose of this study is balanced exercise program according to the supporting surface any affect women's ability to balance high heels. Methods : This study subjects were normal 20 females in their twenties. They were divided into stable supporting surface(n=10), unstable supporting surface(n=10), and they exercised three times a week for 5 weeks. In order to compare the difference of balance, the subjects were measured before and after training. Balance was examined using the balance master 7.0 version systems. Results : 1. There was significant difference values between pre-exercise and post-exercise of unstable surface group on the FORM-EO and FORM EC of MCTSIB and all of Unilateral Stance variables. 2. There was significant difference values between pre-exercise and post-exercise of stable surface group on the mean EPE, mean MXE, and mean DCL of LOS. 3. There was significant difference values between pre-exercise and post-exercise of unstable surface group of the rhythmic weight shift. 4. There was significant difference value in the slow directional control of rhythmic weight shift between groups after exercise. Conclusion : Training on stable supporting surface group and unstable supporting surface group improve balance.