• 제목/요약/키워드: asymmetry ratio

검색결과 198건 처리시간 0.023초

중소기업의 신규상장과 정보비대칭 (IPO of SMEs and Information Asymmetry)

  • 김주환;박진우
    • 아태비즈니스연구
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    • 제11권2호
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    • pp.173-188
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    • 2020
  • Purpose - This study examines the determinants of offer price and short-term and long-term performance of small and medium-sized enterprise(SME) IPO stocks listed on the KOSDAQ during the period from July 2007 to December 2016. Design/methodology/approach - The SME IPO samples are classified into three categories of regular listing, technology-based special listing, and listing by merger with special purpose acquisition company(SPAC), whose results are compared each other and compared to the result for the KOSDAQ listing of large firms. Findings - From the point of SME management which attempts to list its company on the KOSDAQ, the listing by merger with SPAC is the most unfavorable, and the underpricing phenomenon of the technology-based special listing is severe in the second place. By contrast, IPO stock investors can earn the largest abnormal return by purchasing the SPAC which succeeds the merger with unlisted firm, and the next abnormal returns are obtained in the order of the IPO stocks of technology-based special listing, regular listing of SMEs, and regular listing of large firms. However, it is interesting to observe that the net buying ratio of individual investors is relatively large for the IPO stocks of regular listing of SMEs and large firms, which exhibit the long-term under-performance. Research implications or Originality - This result implies that the exceptional listing system such as the technology-based special listing or the listing by merger with SPAC cost the SMEs which bypass the complicated procedure of the regular listing.

A Novel, Deep Learning-Based, Automatic Photometric Analysis Software for Breast Aesthetic Scoring

  • Joseph Kyu-hyung Park;Seungchul Baek;Chan Yeong Heo;Jae Hoon Jeong;Yujin Myung
    • Archives of Plastic Surgery
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    • 제51권1호
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    • pp.30-35
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    • 2024
  • Background Breast aesthetics evaluation often relies on subjective assessments, leading to the need for objective, automated tools. We developed the Seoul Breast Esthetic Scoring Tool (S-BEST), a photometric analysis software that utilizes a DenseNet-264 deep learning model to automatically evaluate breast landmarks and asymmetry indices. Methods S-BEST was trained on a dataset of frontal breast photographs annotated with 30 specific landmarks, divided into an 80-20 training-validation split. The software requires the distances of sternal notch to nipple or nipple-to-nipple as input and performs image preprocessing steps, including ratio correction and 8-bit normalization. Breast asymmetry indices and centimeter-based measurements are provided as the output. The accuracy of S-BEST was validated using a paired t-test and Bland-Altman plots, comparing its measurements to those obtained from physical examinations of 100 females diagnosed with breast cancer. Results S-BEST demonstrated high accuracy in automatic landmark localization, with most distances showing no statistically significant difference compared with physical measurements. However, the nipple to inframammary fold distance showed a significant bias, with a coefficient of determination ranging from 0.3787 to 0.4234 for the left and right sides, respectively. Conclusion S-BEST provides a fast, reliable, and automated approach for breast aesthetic evaluation based on 2D frontal photographs. While limited by its inability to capture volumetric attributes or multiple viewpoints, it serves as an accessible tool for both clinical and research applications.

코스닥 기업의 자본조달 결정요인 (Determinants of Financing Decisions of the KOSDAQ Firms)

  • 곽세영
    • 한국산학기술학회논문지
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    • 제12권12호
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    • pp.5663-5670
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    • 2011
  • 이 논문은 기업의 자본조달과 자본구조를 설명하는 이론으로 대표적인 정태적 절충이론과 자본조달순위이론을 2000년부터 2010년까지 11년간의 기간에 걸쳐서 한국의 중소기업이 주로 상장되어 운영되는 코스닥시장을 대상으로 분석하였다. 코스닥 시장에 거래된 금융업을 제외한 762개의 표본에 대해 전체기간, 전반기 및 하반기의 하위기간으로 구분하여 회귀분석한 결과 부채사용으로 인한 법인세 절약효과와 기업규모 증가에 따라 부채비율이 증가하는 정태적 절충이론의 주장이 일부 지지되지만, 성장기회가 많을수록 부채사용을 선호하고, 수익성이 높을수록 유보이익과 같은 내부자금을 선호함에 따라 레버리지가 감소하는 자본조달순위이론도 일부 지지하는 결과를 얻었으나 감가상각비 등을 이용한 비부채 세금절약은 자본조달 의사결정에 영향을 미치지 않는 것으로 분석되었다.

Stresses around an underground opening with sharp corners due to non-symmetrical surface load

  • Karinski, Y.S.;Yankelevsky, D.Z.;Antes, M.Y.
    • Structural Engineering and Mechanics
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    • 제31권6호
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    • pp.679-696
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    • 2009
  • The paper aims at analyzing the stress distribution around an underground opening that is subjected to non-symmetrical surface loading with emphasis on opening shapes with sharp corners and the stress concentrations developed at these locations. The analysis is performed utilizing the BIE method coupled with the Neumann's series. In order to implement this approach, the special recurrent relations for half plane were proven and the modified Shanks transform was incorporated to accelerate the series convergence. To demonstrate the capability of the developed approach, a horseshoe shape opening with sharp corners was investigated and the location and magnitude of the maximum hoop stress was calculated. The dependence of the maximum hoop stress location on the parameters of the surface loading (degree of asymmetry, size of loaded area) and of the opening (the opening height) was studied. It was found that the absolute magnitude of the maximum hoop stress (for all possible surface loading locations) is developed at the roof points when the opening height/width ratio is relatively large or when the pressure loading area is relatively narrow (compared to the roof arch radius), and contrarily, when the opening height/width ratio is relatively small or when the surface pressure is applied to a relatively wide area, the absolute magnitude of the maximum hoop stress is developed at the bottom sharp corner points.

스위칭 동작 유도 영역과 소멸비 향상 영역으로 구성된 수직 방향성 결합 스위치 설계 (Vertical Directional Coupler Switches with Switching Operation Induced and Extinction Ratio Enhanced Sections)

  • 조성찬;정병민;김부균
    • 대한전자공학회논문지SD
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    • 제38권9호
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    • pp.643-651
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    • 2001
  • 스위칭 동작 유도 영역과 소멸비 향상 영역으로 구성된 수직 방향성 결합 스위치를 제안하였다. 스위칭 동작 유도 영역에서는 두 코어의 굴절율을 변화시키어 cross state와 bar state의 스위칭 동작을 유도하였으며, 소멸비 향상 영역에서의 코어 굴절율의 비대칭을 조절하여 소자의 끝단에서 30dB 이상의 소멸비를 가지는 cross state와 bar state를 얻을 수 있었다. 또한 여러 코어 굴절율 값과 안쪽 클래딩의 두께에 따른 cross state와 bar state의 소멸비 계산 결과의 분석을 통하여 30dB 이상의 높은 소멸비를 보이며 큰 제작 공차를 얻기 위한 수직 방향성 결합 스위치의 설계 지침을 제시하였다.

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PNF 치료가 성인 편마비 환자의 기능회복에 미치는 영향 (The Effect of PNF Method in Functional Restoration of Adult Hemiplegic Patients)

  • 배성수;이근희;황보 각
    • PNF and Movement
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    • 제3권1호
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    • pp.17-26
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    • 2005
  • Objectives : The purpose of this study is to identify influence that PNF method have an effect in function restoration of the impaired patients of central nervous system. Methods : The data were collected by 15 adult stroke patients. The treatment was based on proprioceptive neuromuscular facilitation techniques. Temporal and spatial parameters of gait were analysed for using the computerized GAITRite system. Results : In the comparison of functional ambulation profile(FAP) before and after experiment, the FAP was significantly increased in the PNF method. The gait velocity, cadence and single support time asymmetry ratio was significantly increased in the PNF method. The Motor Assessment Scale was significantly increased in the PNF method. Conclusions : Based on these results, it is concluded that the forced PNF method for 6 weeks can be improve the temporal-spatial gait parameters including FAP in hemiplegic patients. Therefore, the forced PNF method is useful to improve the function restoration in hemiplegic patients. Further study should be done to analyze the effects of intervention duration of treatment, optimal time to apply the treatment in more long peried.

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Two-dimensional concrete meso-modeling research based on pixel matrix and skeleton theory

  • Jingwei Ying;Yujun Jian;Jianzhuang Xiao
    • Computers and Concrete
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    • 제33권6호
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    • pp.671-688
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    • 2024
  • The modeling efficiency of concrete meso-models close to real concrete is one of the important issues that limit the accuracy of mechanical simulation. In order to improve the modeling efficiency and the closeness of the numerical aggregate shape to the real aggregate, this paper proposes a method for generating a two-dimensional concrete meso-model based on pixel matrix and skeleton theory. First, initial concrete model (a container for placing aggregate) is generated using pixel matrix. Then, the skeleton curve of the residual space that is the model after excluding the existing aggregate is obtained using a thinning algorithm. Finally, the final model is obtained by placing the aggregate according to the curve branching points. Compared with the traditional Monte Carlo placement method, the proposed method greatly reduces the number of overlaps between aggregates by up to 95%, and the placement efficiency does not significantly decrease with increasing aggregate content. The model developed is close to the actual concrete experiments in terms of aggregate gradation, aspect ratio, asymmetry, concavity and convexity, and old-new mortar ratio, cracking form, and stress-strain curve. In addition, the cracking loss process of concrete under uniaxial compression was explained at the mesoscale.

회계정보의 차별적 요인에 관한 실증연구 (An Empirical Study on Differential factors of Accounting Information)

  • 오성근;김현기
    • 경영과정보연구
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    • 제12권
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    • pp.137-160
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    • 2003
  • The association between accounting earnings and the stock price of an entity is the subject that has been most heavily researched during the past 25 years in accounting literature. Researcher's common finding is that there are positive relationships between accounting earnings and stock prices. However, the explanatory power of accounting earnings which was measured by $R^2$ of regression functions used was rather low. To be connected with these low results, The prior studies propose that there will be additional information, errors in variables. This study investigates empirically determinants of earnings response coefficients(ERCs), which measure the correlation between earnings and stock prices, using earnings level / change, as the dependent variable in the return/earnings regression. Specifically, the thesis tests whether the factors such as earnings persistence, growth, systematic risk, image, information asymmetry and firm size. specially, the determinable variables of ERC are explained in detail. The image / information asymmetry variables are selected to be connected with additional information stand point, The debt / growth variables are selected to be connected with errors in variables. In this study, The sample of firms, listed in Korean Stock Exchange was drawn from the KIS-DATA and was required to meet the following criteria: (1) Annual accounting earnings were available over the 1986-1999 period on the KIS-FAS to allow computation of variables parameter; (2) sufficient return data for estimation of market model parameters were available on the KIS-SMAT month returns: (3) each firm had a fiscal year ending in December throughout the study period. Implementation of these criteria yielded a sample of 1,141 firm-year observation over the 10-year(1990-1999) period. A conventional regression specification would use stock returns(abnormal returns) as a dependent variable and accounting earnings(unexpected earnings) changes interacted with other factors as independent variables. In this study, I examined the relation between other factors and the RRC by using reverse regression. For an empirical test, eight hypotheses(including six lower-hypotheses) were tested. The results of the performed empirical analysis can be summarized as follows; The first, The relationship between persistence of earnings and ERC have significance of each by itself, this result accord with one of the prior studies. The second, The relationship between growth and ERC have not significance. The third, The relationship between image and ERC have significance of each by itself, but a forecast code doesn't present. This fact shows that image cost does not effect on market management share, is used to prevent market occupancy decrease. The fourth, The relationship between information asymmetry variable and ERC have significance of each by. The fifth, The relationship between systematic risk$(\beta)$ and ERC have not significance. The sixth, The relationship between debt ratio and ERC have significance of each by itself, but a forecast code doesn't present. This fact is judged that it is due to the effect of financial leverage effect and a tendency of interest.

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KOSPI 200 주가지수선물 도입과 주식시장의 비대칭적 변동성 (The Introduction of KOSPI 200 Stock Price Index Futures and the Asymmetric Volatility in the Stock Market)

  • 변종국;조정일
    • 재무관리연구
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    • 제20권1호
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    • pp.191-212
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    • 2003
  • 주가지수선물의 도입은 현물주식시장의 정보 비효율성을 완화시켜 현물주식시장에서 변동성의 비대칭성이 줄어든다는 주가지수선물의 도입 효과를 살펴보기 위하여 KOSPI 200 주가지수 선물 도입 전 후를 대비하여 현물주식시장의 변동성에 대한 비대칭성 정도를 비교분석 하였다. 변동성의 비대칭성을 반영하는 TGARCH 모형을 이용하여 비대칭 비율(asymmetry ratio)을 추정하고 모형의 적합성 검진(diagnostic test)을 통해 비대칭성을 반영하지 않는 GARCH 모형과 비교분석 하였다. 분석결과에 의하면 주가지수선물 도입 이후 현물주식시장의 변동성은 비대칭적 현상이 줄어들었고 그 결과 주가지수선물 도입 이후에는 비대칭성을 고려한 모형과 그렇지 않은 모형간에 적합성의 차이가 미미하게 나타났다. 그러나 현물주식시장의 비대칭적 변동성의 정도는 시장 상승국면에서 보다는 시장 하락국면에서 더 심하게 나타나는데 주가지수선물이 도입되어도 시장하락국면에서 비대칭성이 더 강하게 나타났다. 하만 도입 이전보다는 어느 정도 완화된 것으로 나타나 현물주식시장에서 주가지수선물 도입의 완화 효과를 부정할 수 없을 것으로 판단된다. 한편 동일한 분석기간 동안 주가지수선물시장에서도 변동성의 비대칭성이 발견되었다. 그러나 비대칭적 변동성의 정도가 현물주식시장에 비해서는 상대적으로 적게 나타나 현물주식시장보다는 정보가 가격에 신속하게 반영되고 현물주식시장 보다 공매가 용이하여 양방향의 정보에 모두 자본화할 수 있기 때문으로 사료된다.

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상호억제 기법에 의한 경직성 편마비 환자 보행의 공간적, 시간적 특성 변화 (Characteristics Change of Spatial and Temporal Parameters of Gait in Spastic Hemiplegic Patients by Reciprocal Inhibition)

  • 김종순;이현옥;안소윤;구봉오;배성수
    • The Journal of Korean Physical Therapy
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    • 제16권4호
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    • pp.59-79
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    • 2004
  • The purpose of this study was to determined the effects of reciprocal inhibition on spatial-temporal gait parameters in spastic hemiplegic patients through GaitRite system. The subjects were consisted 45 patients who had spastic hemiplegia due to stroke. All subjects randomly assigned to 3 group : manual reciprocal inhibition program group(manual group), neuromuscular electrical stimulation group(NMES group) and control group. The manual group received voluntary isometric contraction of pre-tibia muscle. The NMES group received neuromuscular electrical stimulation on tibialis anterior. The control group was not recieved any therapeutic intervention. Before and after experiments, spatial-temporal gait parameters and functional ambulatory profile was measure in all patients. The data of 30 patients who complete experimental course were statistically analysed. The results of this study were as following : 1. The percentage of change of functional ambulatory profile were markedly increased in manual group but statistically non significant(p>.01). 2. The percentage of change of gait velocity and cadence were markedly increased in manual group but statistically non significant(p>.01). 3. Asymmetry ratio of gait elements were more improved in manual group but statistically non significant(p>.01). 4. There were no statistical difference between pre-test and post-test with functional ambulatory profile, gait velocity, cadence and asymmetry ratios in NMES group(p>.01). 5. There were no statistical difference between pre-test and post-test with unctional ambulatory profile, gait velocity, cadence and asymmetry ratios in control group(p>.01). In conclusion, the present results revealed that reciprocal inhibition which produced by voluntary isometric contraction of pre-tibia muscle can be improved spatial-temporal gait parameters including functional ambulatory profile in hemiplegic patients. Therefore, reciprocal inhibition is useful to improve functional activities in hemiplegic patient. Further study should be done to analyze the effects of intervention duration of reciprocal inhibition, appropriate muscle contraction, optimal time to apply the reciprocal inhibition in more long period.

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