• Title/Summary/Keyword: Asymmetry effect

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Evaluation of Weighted Correlator for Multipath Mitigation in GPS Receiver (GPS수신기의 다중경로 오차 제거를 위한 가중 상관기의 성능평가)

  • Shin, Mi-Young;Jang, Han-Jin;Suh, Sang-Hyun;Park, Chan-Sik;Hwang, Dong-Hwan;Lee, Sang-Jeong
    • Journal of Navigation and Port Research
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    • v.31 no.5 s.121
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    • pp.409-414
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    • 2007
  • The effect of multipath is especially serious in urban area and sea surface where buildings and water reflect GPS signal. Multipath brings about the performance degradation on many GPS application because the presence of multipath causes the diminution of pseudorange measurement accuracy in turn position accuracy. In this paper, a multipath mitigation named weighted correlation method is implemented on software GPS receiver, in which the asymmetric correlation function is compensated by modifying the late correlation value. Asymmetry compensation is obtained as weighted sum of two correlators which have different early-late chip spaces. This structure is adopted to lessen the computation load lower keeping up performance similar to that. The performance of implemented multipath mitigation technique is evaluated using GPS signal and multipath signal generated by GPS signal generator and software GPS receiver. The test results show that the weighted correlation method gives hefter performance than the standard correlator and the narrow correlator.

Morphological Features of Bedforms and their Changes due to Marine Sand Mining in Southern Gyeonggi Bay (경기만 남부에 발달된 해저지형의 형태적 특징 및 해사채취에 의한 변화)

  • Kum, Byung-Cheol;Shin, Dong-Hyeok;Jung, Seom-Kyu;Jang, Seok;Jang, Nam-Do;Oh, Jae-Kyung
    • Ocean and Polar Research
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    • v.32 no.4
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    • pp.337-350
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    • 2010
  • This study conducted sedimentological and geophysical surveys for 3 years (2006-2008) in southern Gyeonggi Bay, Korea to elucidate temporal changes in subaqueous dune morphology on a sand ridge trending northeast to southwest that has been excavated by marine sand mining. The sand ridge (~20 m in height, ~2 km in width and 3~4 km in length) has a steep slope on the NW side and a gentle slope on the SE side, creating an asymmetric profile. Large (10~100 m in length) and very large (>100 m in length) dunes occurring on the SE side of the ridge show a northeastward asymmetrical shape, whereas dunes on the NW side destroyed by marine sand mining display a southwestward asymmetry. The comparison between Flemming (1988)'s correlation and the height-length correlation of this study indicates that tidal current and availability of sand sediment are major controlling factors to the development and maintenance of dunes. Depth and sedimentary characteristics (grain size) are not likely to be major controlling factors, but indirectly influence dune growth by hydrological and sedimentary processes. The length and the height of dunes decrease toward the southeastern trough away from the crest of the ridge. These features result from the decrease of tidal current and sediment availability. The length and the height of dunes on the southeast side decrease gradually over time. This is a result of the interaction between tidal current and the decrease in sediment availability due to sediment extraction by marine sand mining. Marine sand mining has destroyed the dunes directly, causing irregular shapes of shorter length and lower height. The coarse fraction of suspended sediments is transported and deposited very close to the sand pit. By contrast, relatively fine sediments are transported by the tidal current and deposited over a wide range by the settling-lag effect, resulting in a decrease of sediment grain size in the area where suspended sediments are deposited. In addition, marine sand mining, decreases the height of dunes. Therefore, morphological and sedimentological characteristics of dunes around the sand pits will be significantly changed by future sand mining activities.

Hemispheric Asymmetry in Processing Semantic Relationship Shown in Normals and Aphasic (형태소 공유 어휘의 심성 어휘집 표상 양식)

  • Jung, Jae-Bum;Lee, Hong-Jae;Moon, Young-Sun;Kim, Dong-Hyu;Pyun, Sung-Bum;Nam, Ki-Chun
    • Annual Conference on Human and Language Technology
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    • 1999.10e
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    • pp.359-367
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    • 1999
  • 형태소를 공유하고 있는 어휘가 심성 어휘집(mental lexicon)에 어떻게 저장되어 있고 어떻게 어휘 접근되는지에 관하여 여러 설명이 제기되었다 첫 번째 가설은 형태소 공유 어휘는 심성 어휘집에 모두 같은 어근 혹은 어간을 중심으로 저장되어 있다는 것이다. 두 번째 가설은 어간이나 어근으로의 분석을 통해 활용된 단어를 이해하는 것이 아니라 일단 활용된 형태의 어휘를 심성 어휘집에서 찾고, 만일 해당되는 것이 발견되면, 그 활용된 어절의 이해가 끝나게 되고, 만일에 해당되는 것이 심성 어휘집에 존재하지 않는 경우에만 부수적인 과정으로 구성 형태소로의 분석이 이루어진다는 것이다. 세 번째 가설은 어휘의 품사, 어휘의 빈도, 형태소 활용의 규칙성 등에 따라 구성 형태소로의 분석을 통해 활용된 단어를 이해하거나 아니면 활용된 어휘의 직접적인 접근을 통해 활용된 단어를 이해한다는 것이다. 본 연구에서는 이 세 종류의 가설 중에 어느 가설이 옳은 것인지를 조사하기 위해, "먹은" 흑은 "쥐어"와 같은 한국어 어절을 이용하여 형태소 표상 양식과 이해 과정을 다루었다. 본 연구의 목적을 위해 점화 어휘 판단 과제(primed-lexical decision task)를 사용하였다. 실험 1은 "먹은"처럼 동사 "먹다"로도 해석이 가능하고 명사 "먹"으로도 가능한 중의적 어절을 점화 문자열로 제시하고 이 문자열이 두 의미와 관련된 목표 단어 재인에 어떤 영향을 끼치는지를 조사하였다. 만일에 "먹"이라는 어근 혹은 어간으로의 분석을 통해 이 어절을 이해한다면 두 종류의 의미와 관련된 조건 모두에서 촉진적 점화 효과(facilitatory priming effect)가 나타날 것이고, 어절 전체로의 어휘 접근 과정이 일어난다면 사용빈도에서 높은 동사 뜻과 관련된 조건에서만 촉진적 점화 효과가 나타날 것이다. 실험 1의 결과는 두 종류의 의미가 모두 활성화되는 것을 보여 주었다. 즉, "먹은"과 간은 어절 이해는 구성 형태소로의 분석과 구성 형태소 어휘 접근을 통해 어절 이해가 이루어진다는 가설을 지지하고 있다. 실험 2에서는 실험 1과 다르게 한 뜻으로만 안일 수밖에 없는 "쥐어"와 같은 어절을 사용하여 이런 경우에도(즉, 어절의 문맥이 특정 뜻으로 한정하는 경우) 구성 형태소로의 분석 과정이 일어나는지를 조사하였다. 실험 2의 결과는 실험 1의 결과와는 다르게 어간의 한가지 의미와 관련된 조건만 촉진적 점화 효과가 나타나는 것을 보여주었다. 특히, 실험 2에서 SOA가 1000msec일 경우, 두 의미의 활성화가 나타나는 것을 보여주었는데, 이 같은 결과는 어절 문맥이 특정한 의미로 한정시킬 경우는 심성어휘집에 활용형태로 들어있다는 것이다. 또한 명칭성 실어증 환자의 경우에는 즉시적 점화과제에서는 일반인과 같은 형태소 처리과정을 보였으나, 그이후의 처리과정이 일반인과 다른 형태를 보였다. 실험 1과 실험 2의 결과는 한국어 어절 분석이 구문분석 또는 활용형태를 통해 어휘 접근되는 가설을 지지하고 있다. 또 명칭성 실어증 환자의 경우에는 지연된 점화과제에서 형태소 처리가 일반인과 다르다는 것이 밝혀졌다. 이 결과가 옳다면 한국의 심성 어휘집은 어절 문맥에 따라서 어간이나 어근 또는 활용형 그 자체로 이루어져 있을 것이다.

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Temperature Effect on the Optical Properties of YAG and Silicate Phosphor-based White Light Emitting Diodes (온도 변화에 따른 YAG 및 Silicate형광체 기반 백색 LED의 광특성 변화에 대한 연구)

  • Choi, Hyun-Woo;Ko, Jae-Hyeon
    • Korean Journal of Optics and Photonics
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    • v.24 no.3
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    • pp.135-142
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    • 2013
  • Two white light emitting diodes(LEDs) were fabricated by using two kinds of yellow phosphor, YAG:Ce and $(Sr,Ba)_2SiO4:Eu$, and their spectroscopic properties were analyzed as a function of temperature from room temperature to $80^{\circ}C$. The asymmetric double sigmoidal function was applied to both blue and yellow peaks of the emitting spectrum to obtain the center wavelength, the amplitude, the half width, and the skewness parameters. According to this analysis, the center wavelength of the blue peak shifted to longer wavelength while that of the yellow peak shifted to shorter wavelength. In addition, some of the skewness parameters were found to increase upon heating, which indicates that spectrum asymmetry becomes enhanced at higher temperatures. The changes in the color coordinates and the luminous efficacy were larger for the case of silicate-based white LED. These results suggest that the silicate-based white LED is inferior to the YAG-based white LED from the viewpoint of color stability, efficacy and color rendering index.

The Impact of Corporate's Name Change on Cost of Capital (상호변경이 내재자본비용에 미치는 영향)

  • Yu, Soon-Mi
    • Management & Information Systems Review
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    • v.33 no.4
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    • pp.21-38
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    • 2014
  • This study investigates whether and how a firm's cost of equity is influenced by the extent of a firms's name change. Even though corporate name change doesn't give any benefit to investors, it can be a signaling about firm's future valuation. And also, if that signaling has high credibility, it can be decrease information cost and the firm's cost of equity. on the contrary to this, if corporate name change is kind of break with the past and corporate image laundering, it is bad signaling to investors. So it can be increase information risk and the firm's cost of equity. Using yearly cross-sectional regressions of the cost of equity on our proxies for corporate name change, size, beta, market-to-book ratio and other innate risk factor over the 2005-2010, we find that the cost of capital is positively associated with corporate name change after controlling for all other factors. This result implies that corporate name change increase information risk of the business, and thus increase information asymmetries between managers and outside investors with respect to a firm's true future value. This increases information risk, and creates an adverse selection problem, on the part of outside investors. Rational investors therefore demand a premium for bearing this corporate name change-related information risk, which in turn leads us to observe a positive relation between the intensity of corporate name change and the cost of equity.

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$^{13}C$ NMR Analysis for the Characterization of Heme Electronic/Molecular Structure in Horse Myoglobin Cyanide (Myoglobin 시안 단백질에 포함된 Heme에 대한 전자 및 분자구조 규명을 위한 $^{13}C$ NMR분석)

  • Lee, Kang-Bong;Kweon, Jee-Hye;Lee, Ho-Jin;Kim, Young-Man;Choi, Young-Sang
    • Analytical Science and Technology
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    • v.11 no.1
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    • pp.73-78
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    • 1998
  • The reverse detection heteronuclear multiple quantum coherence, HMQC study of metcyano complex of horse myoglobin(MbCN) has provided the complete assignment of hyperfine shifted resonances of heme carbons attached with proton(s). The application of HMQC experiment to the paramagnetic low-spin MbCN gives clear $^1H$ and $^{13}C$ coherences for the paramagnetic amino acid residues as well as heme side chains, and can be extended to the low-spin paramagnetic hemoprotein derivative for the assignment of natural abundance $^{13}C$ resonances. This assignment strategy can avoid possible ambiguities that may result from the sole utilization of $^1H$ nuclear Overhauser effect for the assignment of heme $^1H$ signals resonating in the diamagnetic region. The resulting 2,4-vinyl ${\alpha}$-carbons and 7-propionate ${\beta}$-carbon follow anomalous anti-Curie behavior, and are indicative of incoplanarity with heme plane. Magnetic/electronic asymmetry of heme induced by proximal histidine(His) makes spread that the hyperfine shifted heme carbon resonances over the range of 250 ppm at $25^{\circ}C$. These heme carbon resonances would be the much more sensitive probe than those of proton resonances in analyzing the nature of heme electronic structure of myoglobin.

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Arm Swing Asymmetry and Effect of Auditory Cues on Amplitude in the Patients with Parkinson's Disease (파킨슨병 환자의 상지 스윙의 비대칭과 청각신호에 따른 보행 시 진폭에 미치는 영향)

  • Son, Ho-Hee;Kim, Eun-Jung
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.1
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    • pp.344-350
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    • 2013
  • A recent study reporting significantly reduced symmetry in arm swing amplitude in early Parkinson's disease (PD), as measured during gait by auditory cues velocity, led to this investigation of arm swing symmetry and amplitude in PD. The subjects were 14 elderly patients diagnosed with PD. Patients were measured of three conditions performed in random order: slow, general, fast. The auditory cue velocity consisted of a metronome beat ${\pm}20%$ than the subject's general gait speed. Using a motion analysis measurement system, changes in kinematic variables were compared to arm swing analysis. PD groups showed a highly significant reduction of the arm swing amplitude on the more affected body side(MAS)(p<.05). Comparison between the auditory cues velocity, there was a significant increase arm swing amplitude in fast velocity gait than slow and general velocity gait(p<.05). We conclude that motion analysis during gait by auditory cues velocity allows reliable investigation of asymmetric arm movements in early PD patients which attenuate with ongoing disease. The measurement of limb kinematics during gait by auditory cues velocity can broaden our methodological line-up for the analysis of complex motor programs in movement disorders.

The effect of creativity, absorptive capacity and strategic orientation on the distribution strategy of foreign market entry : Focused on Game Industry (해외시장 진입전략에서 창의성과 흡수역량, 전략적 지향성이 미치는 효과에 대한 연구: 게임산업을 중심으로)

  • Park, Young-Eun
    • Review of Culture and Economy
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    • v.17 no.2
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    • pp.29-62
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    • 2014
  • Game industry, one of cultural-content industry which is considered as a typical knowledge-based industry and creative industry, is not like the overseas expansion of traditional manufacture, and has different strategy and performance of export expansion through product or project-based strategy. Therefore, it should be approached by each content unit, and necessary to look at the factors that make their decision makings of foreign market entry vary. This study focuses on discovering creativity, absorptive capacity and strategic orientation(market orientation and innovation orientation) which affect the difference of distribution's decision making of entry into foreign market in game industry This paper examined 252 cases of online games in order to investigate creativity, absorptive capacity and strategic orientations for each foreign market and what entry type(among licensing, joint distribution, exclusive distribution) they chose according to the products developed in team level. This helps us analyze the factors affecting market orientation and innovation orientation in the perspectives of creativity and absorptive capacity in comprehensive way, and notice the phenomena which use different foreign distribution strategy though there are company incorporated abroad and their results. This study supplements the limit of the existing Resource-Based View, Resource-Dependent View, and traditional international business theories such as Transaction Cost Theory or OLI Paradigm(Eclectic Framework), and proves how company could reduce asymmetry of uncertainty and information in creative industry and whether they accomplish successful overseas expansion according to strategic orientations.

The Impact of Industry-level Competition on the Excess Stock Returns due to Changes in Cash Holdings (산업 내 경쟁정도가 보유현금의 변화에 따른 초과수익률에 미치는 영향)

  • Cho, Jung Eun
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.20 no.5
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    • pp.163-169
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    • 2019
  • This study examined whether industry-level competition affects excess stock returns because of changes in cash holdings. Competitive inter-company threats increase the possibility of the manager's replacement, and function to induce management to make their best efforts, resulting in the amount and quality of the information provided by the enterprise increasing. Therefore, as competition intensifies, agency problems are reduced and stock returns increase because the company's cash holdings are expected to increase. However, there is a view that firms in industries with severe competition tend to have high information asymmetry because competitors may compete in more favorable positions by using detailed information disclosed by the competing firms. Accordingly, as market competition intensifies, the excess stock returns resulting from increased cash holdings are expected to decline. These results show that excess stock returns because of increases in cash holdings increase as the degree of competition in the industry intensifies, thus supporting the positive effect of market competition. Overall, the results of this study provide an understanding that market competition plays an effective external governance mechanism and that investors positively evaluate the cash held by companies with severe industry competition.

Systemic literature review on the impact of government financial support on innovation in private firms (정부의 기술혁신 재정지원 정책효과에 대한 체계적 문헌연구)

  • Ahn, Joon Mo
    • Journal of Technology Innovation
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    • v.30 no.1
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    • pp.57-104
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    • 2022
  • The government has supported the innovation of private firms by intervening the market for various purposes, such as preventing market failure, alleviating information asymmetry, and allocating resources efficiently. Although the government's R&D budget increased rapidly in the 2000s, it is not clear whether the government intervention has made desirable impact on the market. To address this, the current study attempts to explore this issue by doing a systematic literature review on foreign and domestic papers in an integrated way. In total, 168 studies are analyzed using contents analysis approach and various lens, such as policy additionality, policy tools, firm size, unit of analysis, data and method, are adopted for analysis. Overlapping policy target, time lag between government intervention and policy effects, non-linearity of financial supports, interference between different polices, and out-dated R&D tax incentive system are reported as factors hampering the effect of the government intervention. Many policy prescriptions, such as program evaluation indices reflecting behavioral additionality, an introduction of policy mix and evidence-based policy using machine learning, are suggested to improve these hurdles.