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The Efficiency of Bank Underwriting of Corporate Securities in Korea (국내 자본시장 증권인수기능의 효율성에 관한 연구 : 은행계열과 비은행계열 금융기관 비교 분석)

  • Baek, Jae-Seung;Lim, Chan-Woo
    • The Korean Journal of Financial Management
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    • v.27 no.1
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    • pp.181-208
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    • 2010
  • In July 2007, Korean government has passed "The Capital Market and Financial Investment Services Act" to further develop the capital markets and the Act was to become effective in February 2009. Using a large sample of Korean firms, we have examined (i) the effect of underwriting activities on the firm value (bond spread) comparing commercial bank and investment bank, and (ii) the determinants of the firm value changes following underwriting activities of bank. To test our goal, we collected a wide range of samples of data for bond issuing activities executed by Korean firms listed on the Korea Stock Exchange (KSE) between 2000 and 2003. Our paper is distinguished from previous studies on this subject in a way that we analyzed the effect of corporate bond underwriting activities with regard to commercial banking and investment banking. Initially, we set up a hypothesis that "Certification View" and "Conflict-of-interest View" are major driving forces behind cross-firm differences in performance following bond issuance. We find that, in general, underwriting by investment bank (securities company) brings a positive effect on the firm value (spread between bench mark rate and bond issuing rate). This result indicates that firm value has been negatively affected by the bank underwriting and provides the evidence for "Conflict-of-interest View" in Korea. Our studies have also revealed that any change in firm value following bond issuance is positively related with the firm size (total asset), operating performance, liquidity (cashflow), and equity ownership by foreign investors. Overall, our results support the view that bank underwriting activities can play an important role in determining firm value and financial strategies under "The Capital Market and Financial Investment Services Act" of 2007.

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Development of a Safety and Health Expense Prediction Model in the Construction Industry (건설업 산업안전보건관리비 예측 모델 개발 - 일반건설공사(갑)의 공사비 50억미만 공사를 대상으로 -)

  • Yeom, Dong Jun;Lee, Mi Young;Oh, Se Wook;Han, Seung Woo;Kim, Young Suk
    • Korean Journal of Construction Engineering and Management
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    • v.16 no.6
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    • pp.63-72
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    • 2015
  • The importance of the appropriate use and procurement of Safety and Health Expense has been increasing along with the recent increase of construction projects in height, size and complexity. However, the current standards for deducting the Safety and Health Expense have shown limitations in applying the properties and environment of the construction project due to its Safety and Health Expense Rate's classification method. Therefore, the purpose of this study is to develop a prediction model for the Safety and Health Expense that enables the consideration of different environment and properties of construction projects. The study uses multiple regression analysis to analyze the Safety and Health Expense of Ordinary(A) of less than 0.5 billion WON. The research results have shown that the use of multiple regression analysis reduces the error rate to 4.38% which the current standard calculation method have shown 18.48%. Therefore, the use of the suggested model provides reliable Safety and Health Expense prediction values that considers the properties of the project. It is expected that the results of this study contributes to the effective safety management by providing the appropriate amount of Safety and Health Expense to the project. In this study, only projects of less than 5 billion WON have been considered in the analysis. Therefore, more data is required for future studies to suggest an overall Safety and Health Expense predict ion model that covers the whole construction industry.

Blood Pressure Cuff Bladders Tailored For Koreans (한국인 맞춤형 혈압계 커프 블래더)

  • Hwang, Lark Hoon;Park, Woo Sung;Na, Seung Kwon
    • The Journal of Korean Institute of Communications and Information Sciences
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    • v.38C no.9
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    • pp.822-829
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    • 2013
  • Hypertension is one of the most common clinical diseases, with an increasing prevalence globally. Hypertension triggers various harmful consequences and affects multiple organs. Life-long care may be required in some cases. According to the Korea Center for Disease Control and Prevention, the prevalence of hypertension is gradually increasing. A 2011 survey revealed that 28.9% of Korean adults had hypertension. The prevalence rates were slightly higher among men than women. Accurate measurement of blood pressure(BP) is crucial to classify patients, to identify BP-related risks, and to inform correct treatment. For accurate blood pressure measurement, the use of a cuff bladder size appropriate for the mid-upper arm circumference(MUAC) is essential. Incorrect sized cuff bladder is one of the main causes of equipment error affecting sphygmomanometer accuracy. When commercial sphygmomanometers were examined, the cuff bladders differed from the dimensions specified in the ISO 81060-1:2007 standards. Undercuffing is responsible for a spurious overestimation of BP in patients with large arms leading to overdiagnosis of hypertension, whereas overcuffing (that is, use of relatively large cuffs with small arms), may be responsible for an opposite problem, leading to erroneous underestimation of BP levels. The cuff bladder sizes recommended by the American Heart Association(AHA) are an arm circumference(AC) of 17-25 cm for small-sized adults, AC of 24-32 cm for adults, AC of 32-42 cm for normal-sized adults, and AC of 42-50 cm for obese adults. In contrast, the AC of Korean adults ranges from 23-31 cm, belonging to a single type of adult bladder. Three types of bladders are necessary for Korean adults with an AC of 23-31cm. Hospitals often use one or two differently-sized Western cuffs for adult patients, which can yield inaccurate BP determinations. Cuff bladders with dimensions based on anthropometric reference data obtained from Koreans will aid hospitals to measure BP more accurately.

The Learning Curve of Laparoscopy-assisted Distal Gastrectomy (LADG) for Cancer (학습곡선을 기준으로 한 복강경 보조 원위절제술에 대한 결과)

  • Kim, Kab-Choong;Yook, Jeong-Hwan;Choi, Ji-Eun;Cheong, Oh;Lim, Jeong-Taek;Oh, Sung-Tae;Kim, Byung-Sik
    • Journal of Gastric Cancer
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    • v.8 no.4
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    • pp.232-236
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    • 2008
  • Purpose: Laparoscopic surgery for gastric cancer was introduced in the past decade because it was considered less invasive than open surgery, and this results in less postoperative pain, faster recovery and an improved quality of life. Several studies have demonstrated the safety and feasibility of this procedure. We examined the outcome of performing laparoscopic surgery for gastric cancer over the last two year. Materials and Methods: From April 2004 to December 2006, 329 patients with gastric adenocarcinoma underwent a laparoscopy-assisted distal gastrectomy with lymph node dissection. The data was retrospectively reviewed in terms of the clinicopathologic findings, the perioperative outcomes and the complications. Results: The total patient group was comprised 196 men (59.6%) and 133 women (40.4%). The mean BMI was 23.6 and the mean tumor size was 2.7 cm. The mean number of harvested lymph node was 22.7, and this was 18.6 before 30 cases and 23.1 after 30 cases, and the difference was significant (P=0.02). The mean operation time was 180.9 min, and this was than 287.9 min before 30 cases and 170.2 min after 30 cases. After 30 cases, there was a significant improvement of the operation time (P<0.01). The mean incision length after 30 cases was shorter than that before 30 cases (P<0.01). Postoperative complications occurred in 24 (7.3%) of 329 patients and there was no conversion to open surgery. Conclusion: Even though the LADG was accompanied by a difficult learning curve, we successfully performed 329 LADG procedures over the past 2 years and we believe that LADG is a safe, feasible operation for treating most early gastric cancers (EGC).

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Research on the Prototype Landscape of Former Donam SeoWon Located in YeonSan (연산 돈암서원(豚巖書院) 구지(舊址)의 원형경관 탐색)

  • Rho, Jae-Hyun;Choi, Jong-Hee;Shin, Sang-Sup;Lee, Won-Ho
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.30 no.4
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    • pp.14-22
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    • 2012
  • The position, size and landscape of the former Donam SeoWon as well as the physical organization of the old site, are studied to extract data for the enhancement of the authenticity of Donam SeoWon since its registration as a world heritage site. The results are as follows. The 'Donam(豚巖)' encaved rock, the tombstone of teacher Sagye(沙溪), Kimjipsadang(金集祠堂), the head of the Gwangsan Kim family, the Sagye stream in front of them, and the Gyeryong and Daedun mountains in the distance are united in the former Donam SeoWon as landscape elements that clearly show the characteristics of the former site, which was called 'Donam-Wollim(豚巖園林).' Moreover Yangseongdangsipyoung(養性堂十詠), adds the garden elements of a medical herb field, twins pond, a bamboo forest, a school, and a peach field. On this site, one can also engage in activities that are related to the land and are closely related to Neo-Confucianism such as fish watching, conferencing, visit in seclusion(訪隱), looking for monks, and overseeing farming. The former site facing east is assumed to have Sau(祠宇) - Eungdodang(凝道堂) - Ipdeokmum(入德門) - Sanangru(山仰樓: estimated). Jeonsacheong seems to have been located to the left of the Sau area, Yangseongdang, which contained upper and lower twin lotus ponds, on the right and was surrounded by various plants. As it has been used as a lecture hall for the past 250 years, the former Donam SeoWon, located 1.8km away from the current area, must be preserved, and the landscape should be formed to establish the authenticity of Donam SeoWon.

Review of the Modern Values of East and West Moat Culture (동·서양 해자(垓字) 문화의 현대적 가치 재조명)

  • Jung, Yong-Jo
    • Journal of the Korean Institute of Traditional Landscape Architecture
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    • v.35 no.1
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    • pp.25-35
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    • 2017
  • The purpose of this study is to re-exam of the modern values of a moat to utilize it with various functions such as a military defense on the outskirts of the castle, dividing the space by its boundary, controlling the micro-climate in the worsening modern environment with temperature rise due to climate change and habitat reduction of animals, and providing the habitat of animals to modern urban space, etc. The scope of the study is focusing on the castles with the moat installed to prevent the enemy from accessing directly to the wall using a pond or water path for military defense on the outskirts of the castle or to divide it into boundaries. In the Orient, the Nakan Eupseong, Haemi Eupseong, Gyeongju Wolseong in Korea and the Forbidden City in China, and Nijo Castle and Osaka Castle in Japan were selected. In the West, Edinburgh Castle in Britain, Blois Castle in France, Chillon Castle in Switzerland, and Frederiksborg Castle in Denmark were selected for the study. As a research method, literature research and field research were conducted. For the Orient, it was conducted in parallel with the literature research and field research. For the western, it was mainly conducted with literature research. For the literature research, the origin of the moat, the concept of the moat, the function of the moat, the history and culture of the western moat are based on the data from the related institutions and previous studies. For the Orient field research, exploring was conducted in two to three times from Jan. 2016 to Dec. 2016 in each of the target areas of Nakan Eupseong, Haemi Eupseong, Gyeongju Wolseong in Korea and the Forbidden City in China, and Nijo Castle and Osaka Castle in Japan. The contents of the research were analyzed through interviews, photographs, measurements, and observations on the function, size, and characteristics of the moat of each target. The results of this study are as follows. The moat was a structure installed to set a boundary for military defense facilities on the outskirts of a castle and it played an important role as a part of the city in the ancient times of Asia and the West through the Middle Ages. The role of the moat is gradually disappearing due to the disappearance of the purpose of military defense. However, moats are excluded from modern landscape planning, despite the fact that a moat filled with water is a hydrophilic space with great historical and cultural value such as various cultural activities and providing habitats for animals. By reflecting on the moats various functions in modern cities and utilizing it, it is expected to be utilized to bring pleasant air into the city where the circulation of air is blocked and energize the city as a hydroponic element.

Least-Square Fitting of Intrinsic and Scattering Q Parameters (최소자승법(最小自乘法)에 의(衣)한 고유(固有) Q와 산란(散亂) Q의 측정(測定))

  • Kang, Ik Bum;McMechan, George A.;Min, Kyung Duck
    • Economic and Environmental Geology
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    • v.27 no.6
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    • pp.557-561
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    • 1994
  • Q estimates are made by direct measurements of energy loss per cycle from primary P and S waves, as a function of frequency. Assuming that intrinsic Q is frequency independent and scattering Q is frequency dependent over the frequencies of interest, the relative contributions of each, to a total observed Q, may be estimated. Test examples are produced by computing viscoelastic synthetic seismograms using a pseudo spectral solution with inclusion of relaxation mechanisms (for intrinsic Q) and a fractal distribution of scatterers (for scattering Q). The composite theory implies that when the total Q for S-waves is smaller than that for P-waves (the usual situation), intrinsic Q is dominating; when it is larger, scattering Q is dominating. In the inverse problem, performed by a global least squares search, intrinsic $Q_p$ and $Q_s$ estimates are reliable and unique when their absolute values are sufficiently low that their effects are measurable in the data. Large $Q_p$ and $Q_s$ have no measurable effect and hence are not resolvable. Standard deviation of velocity $({\sigma})$ and scatterer size (A) are less unique as they exhibit a tradeoff as predicted by Blair's equation. For the P-waves, intrinsic and scattering contributions are of approximately the same importance, for S-waves, the intrinsic contributions dominate.

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Effect of moisture on sealing ability of root canal filling with different types of sealer through the glucose penetration model (수종의 실러를 이용한 근관 충전 시 근관 내 수분이 치근단 폐쇄효과에 미치는 영향)

  • Jang, Jin-Ah;Kim, Hee-Lyang;Her, Mi-Ja;Lee, Kwang-Won;Yu, Mi-Kyung
    • Restorative Dentistry and Endodontics
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    • v.35 no.5
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    • pp.335-343
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    • 2010
  • Objectives: To compared the effect of different levels of moisture of root canal on the sealing ability after filling with four different types of sealer. Materials and Methods: Single-rooted teeth (n = 90) instrumented to and apical size of 0.06 / 45 were randomly assigned to 12 experimental groups (n = 7 per group), positive/negative control groups (n = 3 per group). The teeth of the experimental groups (a. DRY; b. PAPER POINT DRY; c. WET) were obturated with sealer (Group 1-3: Sealapex; Group 4-6: AH plus; Group 7-9: Tubuli-seal; Group 10-12: EndoRez) and warm vertical compaction method. After 7 days in $37^{\circ}C$, 100% humidity, the coronal-to-apical microleakage was evaluated quantitatively using a glucose leakage model. The leaked glucose concentration was measured with spectrophotometer at 1, 3, 7, 14, 21, and 30 days. Data were recorded ad mmol/L and statistically analysed with the two-way ANOVA and Duncan test (p = 0.05). Results: Throughout the experimental period Tubuli-seal/WET (Group 9) showed the highest mean cumulative glucose penetration (178.75 mmol/L), whereas AH plus/DRY (Group 4) had the least (20.78 mmol/L). Conclusions: The results of this study demonstrated that the moisture condition of root canals at the time of obturation and the type of sealer that was used had a significant effect on leakage and sealing ability. Thus drying procedure according to sealer types is a critical step and should not be missed in endodontic treatment.

Attention to the Internet: The Impact of Active Information Search on Investment Decisions (인터넷 주의효과: 능동적 정보 검색이 투자 결정에 미치는 영향에 관한 연구)

  • Chang, Young Bong;Kwon, YoungOk;Cho, Wooje
    • Journal of Intelligence and Information Systems
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    • v.21 no.3
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    • pp.117-129
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    • 2015
  • As the Internet becomes ubiquitous, a large volume of information is posted on the Internet with exponential growth every day. Accordingly, it is not unusual that investors in stock markets gather and compile firm-specific or market-wide information through online searches. Importantly, it becomes easier for investors to acquire value-relevant information for their investment decision with the help of powerful search tools on the Internet. Our study examines whether or not the Internet helps investors assess a firm's value better by using firm-level data over long periods spanning from January 2004 to December 2013. To this end, we construct weekly-based search volume for information technology (IT) services firms on the Internet. We limit our focus to IT firms since they are often equipped with intangible assets and relatively less recognized to the public which makes them hard-to measure. To obtain the information on those firms, investors are more likely to consult the Internet and use the information to appreciate the firms more accurately and eventually improve their investment decisions. Prior studies have shown that changes in search volumes can reflect the various aspects of the complex human behaviors and forecast near-term values of economic indicators, including automobile sales, unemployment claims, and etc. Moreover, search volume of firm names or stock ticker symbols has been used as a direct proxy of individual investors' attention in financial markets since, different from indirect measures such as turnover and extreme returns, they can reveal and quantify the interest of investors in an objective way. Following this line of research, this study aims to gauge whether the information retrieved from the Internet is value relevant in assessing a firm. We also use search volume for analysis but, distinguished from prior studies, explore its impact on return comovements with market returns. Given that a firm's returns tend to comove with market returns excessively when investors are less informed about the firm, we empirically test the value of information by examining the association between Internet searches and the extent to which a firm's returns comove. Our results show that Internet searches are negatively associated with return comovements as expected. When sample is split by the size of firms, the impact of Internet searches on return comovements is shown to be greater for large firms than small ones. Interestingly, we find a greater impact of Internet searches on return comovements for years from 2009 to 2013 than earlier years possibly due to more aggressive and informative exploit of Internet searches in obtaining financial information. We also complement our analyses by examining the association between return volatility and Internet search volumes. If Internet searches capture investors' attention associated with a change in firm-specific fundamentals such as new product releases, stock splits and so on, a firm's return volatility is likely to increase while search results can provide value-relevant information to investors. Our results suggest that in general, an increase in the volume of Internet searches is not positively associated with return volatility. However, we find a positive association between Internet searches and return volatility when the sample is limited to larger firms. A stronger result from larger firms implies that investors still pay less attention to the information obtained from Internet searches for small firms while the information is value relevant in assessing stock values. However, we do find any systematic differences in the magnitude of Internet searches impact on return volatility by time periods. Taken together, our results shed new light on the value of information searched from the Internet in assessing stock values. Given the informational role of the Internet in stock markets, we believe the results would guide investors to exploit Internet search tools to be better informed, as a result improving their investment decisions.

A Template-based Interactive University Timetabling Support System (템플릿 기반의 상호대화형 전공강의시간표 작성지원시스템)

  • Chang, Yong-Sik;Jeong, Ye-Won
    • Journal of Intelligence and Information Systems
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    • v.16 no.3
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    • pp.121-145
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    • 2010
  • University timetabling depending on the educational environments of universities is an NP-hard problem that the amount of computation required to find solutions increases exponentially with the problem size. For many years, there have been lots of studies on university timetabling from the necessity of automatic timetable generation for students' convenience and effective lesson, and for the effective allocation of subjects, lecturers, and classrooms. Timetables are classified into a course timetable and an examination timetable. This study focuses on the former. In general, a course timetable for liberal arts is scheduled by the office of academic affairs and a course timetable for major subjects is scheduled by each department of a university. We found several problems from the analysis of current course timetabling in departments. First, it is time-consuming and inefficient for each department to do the routine and repetitive timetabling work manually. Second, many classes are concentrated into several time slots in a timetable. This tendency decreases the effectiveness of students' classes. Third, several major subjects might overlap some required subjects in liberal arts at the same time slots in the timetable. In this case, it is required that students should choose only one from the overlapped subjects. Fourth, many subjects are lectured by same lecturers every year and most of lecturers prefer the same time slots for the subjects compared with last year. This means that it will be helpful if departments reuse the previous timetables. To solve such problems and support the effective course timetabling in each department, this study proposes a university timetabling support system based on two phases. In the first phase, each department generates a timetable template from the most similar timetable case, which is based on case-based reasoning. In the second phase, the department schedules a timetable with the help of interactive user interface under the timetabling criteria, which is based on rule-based approach. This study provides the illustrations of Hanshin University. We classified timetabling criteria into intrinsic and extrinsic criteria. In intrinsic criteria, there are three criteria related to lecturer, class, and classroom which are all hard constraints. In extrinsic criteria, there are four criteria related to 'the numbers of lesson hours' by the lecturer, 'prohibition of lecture allocation to specific day-hours' for committee members, 'the number of subjects in the same day-hour,' and 'the use of common classrooms.' In 'the numbers of lesson hours' by the lecturer, there are three kinds of criteria : 'minimum number of lesson hours per week,' 'maximum number of lesson hours per week,' 'maximum number of lesson hours per day.' Extrinsic criteria are also all hard constraints except for 'minimum number of lesson hours per week' considered as a soft constraint. In addition, we proposed two indices for measuring similarities between subjects of current semester and subjects of the previous timetables, and for evaluating distribution degrees of a scheduled timetable. Similarity is measured by comparison of two attributes-subject name and its lecturer-between current semester and a previous semester. The index of distribution degree, based on information entropy, indicates a distribution of subjects in the timetable. To show this study's viability, we implemented a prototype system and performed experiments with the real data of Hanshin University. Average similarity from the most similar cases of all departments was estimated as 41.72%. It means that a timetable template generated from the most similar case will be helpful. Through sensitivity analysis, the result shows that distribution degree will increase if we set 'the number of subjects in the same day-hour' to more than 90%.