• Journal of Veterinary Clinics
• /
• v.39 no.6
• /
• pp.326-333
• /
• 2022

The purpose of this study was to evaluate the radiographic positioning techniques used in local animal hospitals, identify the most common positioning problem, and determine whether there were changes after teleradiology consultations. From September 2016 to April 2021, 15 local animal hospitals that requested radiographic interpretation more than 10 times and for more than six cases of thoracic radiographs were selected. Six sets of two-views of (lateral and ventrodorsal [VD] or dorsoventral [DV] views) digital thoracic radiographs from six dogs per hospital were evaluated in four categories. For the lateral view, radiographic technique scores used in ten local animal hospitals improved, one remained the same, and four became worse. For the VD/DV view, the score for eleven hospitals improved and worsened for four. The most common problem was rotation (57/90) for the lateral view, followed by an inappropriate field of view (59/90), and incorrect beam center (71/90). For the VD/DV view, an inappropriate field of view (54/90) was the most common problem, followed by asymmetry (63/90), and incorrect beam center (73/90). Every factor, except rotation in the lateral view, improved after obtaining technical consultation; however, the degrees of improvement were not remarkable. There was no significant correlation between the number of requests and the degree of improvement. According to the results, the radiographic technique used in local animal hospitals was improved by technical advice on teleradiology. These changes make it possible to provide accurate diagnoses of the requested images. There are some limitations regarding the indicators of evaluation and the number of cases; therefore, further studies that use detailed indicators in large cohort group are needed. In addition, an effective method of teaching should be developed to improve radiographic techniques in local animal hospitals.

• The Journal of The Korea Institute of Intelligent Transport Systems
• /
• v.22 no.3
• /
• pp.160-174
• /
• 2023

LiDAR plays a key role in autonomous vehicles, and to improve its visibility, it is necessary to improve its performance and the detection objects. Accordingly, this study proposes a shape for traffic safety signs that is advantageous for self-driving vehicles to recognize. Improvement plans are also proposed using a shape-recognition algorithm based on point cloud data collected through LiDAR sensors. For the experiment, a DBSCAN-based road-sign recognition and classification algorithm, which is commonly used in point cloud research, was developed, and a 32ch LiDAR was used in an actual road environment to conduct recognition performance tests for 5 types of road signs. As a result of the study, it was possible to detect a smaller number of point clouds with a regular triangle or rectangular shape that has vertical asymmetry than a square or circle. The results showed a high classification accuracy of 83% or more. In addition, when the size of the square mark was enlarged by 1.5 times, it was possible to classify it as a square despite an increase in the measurement distance. These results are expected to be used to improve dedicated roads and traffic safety facilities for sensors in the future autonomous driving era and to develop new facilities.

• Journal of the Korean Orthopaedic Association
• /
• v.56 no.5
• /
• pp.413-418
• /
• 2021

Purpose: To investigate the effect of facet tropism on the degeneration of facet joint and intervertebral disc in the cervical spine. Materials and Methods: From January 2017 to December 2018, cervical tropism of 100 patients at the C5/6 level was analyzed retrospectively. In computed tomography (CT), the orientation and tropism of the facet joint with respect to the sagittal, coronal, and horizontal planes were measured. Regression of the facet joint in magnetic resonance imaging (MRI) and CT was assessed using a grading system. Intervertebral disc degeneration was assessed and divided into five grades on MRI. For the left and right asymmetry, a difference between two facet angles of less than 7° was classified as the control group, more than 7° was classified as the tropism group. Results: The mean age of the patients was 55.44±12.3 years (31-81 years) in the tropism group and 55.66±10.7 years (32-76 years) in the control group. In the tropism group, 32 were male and 18 were female. In the control group, 24 were male and 26 were female. Facet joint degeneration was identified in 24 patients (48.0%) in the tropism group and 14 patients (28.0%) in the control group, showing a significant difference. Intervertebral disc degeneration was identified in 29 patients (58.0%) in the tropism group and 17 patients (34.0%) in the control group, showing a significant difference. Multivariate revealed, tropism to be a factor that affected the facet joint and intervertebral disc degeneration. Conclusion: Facet joint and intervertebral disc degeneration occurred significantly in the tropism group, and tropism is a factor affecting the degeneration of facet joint and intervertebral disc in the C5/6 level.

• The Korean Journal of Financial Management
• /
• v.23 no.2
• /
• pp.109-141
• /
• 2006

The central factor in the pecking order theory of financial structure is the asymmetric distribution of information between managers and less-informed outside investors. Myers and Majluf (1984) show that this asymmetry leads managers to prefer internal funds to external funds. Funds are raised through equity issues only after the capacity to issue debt has been exhausted. In contrast, according to static tradeoff theory, an optimum financial structure exists by the tradeoff between tax saving by debt and bankruptcy costs. This study examines the recent changes of Korean firms' financial structure and financing behavior and the determinants of financial structure. The sample of firms comes from the period of $1996{\sim}2004$, and the number of firms is 32,003. The major findings are as follows. First, in contrast with previous studies using US firms as sample, Korean firms have been using debt financing as their major financing instrument. Especially, the firms in the fund deficit situation relies much more on $long{\sim}term$ and $short{\sim}term$ debts rather than on equity issues. Second, as is the case with previous studies using US firms sample indicates, the financing deficit variable can not explain perfectly the net debt issue. However, compared with net equity issue variable, net debt issue variable is more closely related to the financing deficit variable. Third, when financing deficit variable is added to the current list of explanatory variables of financial structure determinants model, it has a significant and positive explanatory power. In addition, the coefficients of determinants are much improved. Thus, it is concluded that although pecking order theory is not perfect, it appears to be more useful compared to static tradeoff theory, at least in explaining the recent financing behavior of Korean manufacturing firms.

• Journal of the Institute of Electronics Engineers of Korea TC
• /
• v.45 no.4
• /
• pp.9-21
• /
• 2008

In this paper, we propose a GNSS-based RF receiver, A high precision localization architecture, and a high sensitivity localization architecture in order to solve the satellite navigation system's problem mentioned above. The GNSS-based RF receiver model should have the structure to simultaneously receive both the conventional GPS and navigation information data of future-usable Galileo. As a result, it is constructed as the multi-band which can receive at the same time Ll band (1575.42MHz) of GPS and El band (1575.42MHz), E5A band (1207.1MHz), and E4B band (1176.45MHz) of Galileo This high precision localization architecture proposes a delay lock loop with the structure of Early_early code, Early_late code, Prompt code, Late_early code, and Late_late code other than Early code, Prompt code, and Late code which a previous delay lock loop structure has. As we suggest the delay lock loop structure of 1/4chips spacing, we successfully deal with the synchronization problem with the C/A code derived from inaccuracy of the signal received from the satellite navigation system. The synchronization problem with the C/A code causes an acquisition delay time problem of the vehicle navigation system and leads to performance reduction of the receiver. In addition, as this high sensitivity localization architecture is designed as an asymmetry structure using 20 correlators, maximizes reception amplification factor, and minimizes noise, it improves a reception rate. Satellite navigation system repeatedly transmits the same C/A code 20 times. Consequently, we propose a structure which can use all of the same C/A code. Since this has an adaptive structure and can limit(offer) the number of the correlator according to the nearby environment, it can reduce unnecessary delay time of the system. With the use of this structure, we can lower the acquisition delay time and guarantee the continuity of tracking.

• The Korean Journal of Financial Management
• /
• v.21 no.2
• /
• pp.99-123
• /
• 2004

We focus in this study on incremental financing decisions and estimate a logit model for the probability a firm will choose a private placement over a public bond issue. We hypothesize that information asymmetry, financial risk, agent cost, and proprietary information may affect a firm's choice between public debt and private placements. We find that as the size of firm increases, the probability of choosing a private placement declines significantly. The age of the firm, however, is not a significant factor affecting the firm's choice between public and privately-placed bond. The coefficients on the firm's leverage and non-investment grade dummy are significantly positive, meaning firms with high financial risk and credit risk select private placements. The findings regarding agency-related variables, PER and Tobin's Q, are somewhat complex. We find significant evidence that firms with high PER prefer private placements to public bonds, suggesting that borrowers with options to engage in asset substitution or underinvestment are more likely to choose private placements. The coefficient of Tobin's Q is negative, but not significant, which weakly support the hold-up hypothesis. When we construct an interaction term on the Tobin's Q with a non-investment rating dummy, however, the Tobin's Q interaction term becomes positive and significant. Thus, high Tobin's Q firms with a speculative rating are significantly more likely to choose a private placement, regardless of the potential hold-up problems. The ratio of R&D to sales, proxy for proprietary information, is positively significant. This result can be interpreted as evidence in favor of a role for proprietary information in the debt sourcing decision process for these firms.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
• /
• v.18 no.4
• /
• pp.1-20
• /
• 2023

This study attempted to identify the relationship between the investment determinants of accelerators and investment performance through empirical analysis. Through literature review, four dimensions and 12 measurement items were extracted for investment determinants, which are independent variables, and investment performance was adjusted to the cumulative amount of subsequent investment based on previous studies. Performance data from 594 companies selected by TIPS from 2017 to 2019, which are relatively reliable and easy to secure data, were collected, and the subsequent investment cumulative attraction amount, which is a dependent variable, was hypothesized through multiple regression analysis three years after the investment. As a result of the study, 'industrial experience years' in the characteristics of founders, 'market size', 'market growth', 'competitive strength', and 'number of patents' in the characteristics of products and services had a significant positive (+) effect. The impact of independent variables on dependent variables was most influenced by the competitive strength of market characteristics, followed by the number of years of industrial experience, the number of patents, the size of the market, and market growth. This was different from the results of previous studies conducted mainly on qualitative research methods, and in most previous studies, the characteristics of founders were the most important, but the empirical analysis results were market characteristics. As a sub-factor, the intensity of competition, which was the subordinate to the importance of previous studies, had the greatest influence in empirical analysis. The academic significance of this study is that it presented a specific methodology to collect and build 594 empirical samples in the absence of empirical research on accelerator investment determinants, and created an opportunity to expand the theoretical discussion of investment determinants through causal research. In practice, the information asymmetry and uncertainty of startups that accelerators have can help them make effective investment decisions by establishing a systematic model of experience-dependent investment determinants.