• Clinical and Experimental Reproductive Medicine
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• v.4 no.1
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• pp.17-25
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• 1977

Anderson(1937), Power and Barnes(1941) reported a study concerning a method of tubal sterilization in association with peritoneoscopy or laparoscopy in which they cauterized the tubes. There appears to have been a hiatus of interest in sterilization (cold or hot) associated with laparoscopy until reintroduction by Palmer(1963), Frangenheim(1964) and Steptoe(1967). On the other hand, for interval female sterilization, however, minilaparotomy is relatively new. By Saunder and Munsick(1972), John Lyle(1974), Frank Stubb(1974), Vitoon(1973) and B.C. Bai(1975), their own technique for interval female sterilization requires 2.0 to 2.5cm, incision at the margin of the mons pubis. In Korea, female sterilization by means of minilaparotomy firstly reported by B.C. Bai using Bai's uterine elevator, of his own device, early in 1975. Recently inteval female sterilization by laparoscopy and minilaparotomy are widely accepted throughout the world especially in Asian countries. Minilaparotomy is carried out from 1974, laparoscopic sterilization from 1976, and in this study each of 250 cases of those were analysed and discussed for the comparison at Seoul Red Cross Hospital. (1) In the age distribution, numerous clients were in their age of $31{\sim}35$ in laparoscopy as well as minilaparotomy. Average 33.7 years in L and 33.2 years in M. (M=minilaparotomy, L=laparoscopic sterilization) (2) As regarding living children, women having 3 children represented the greatest number, 113 cases out of 250 in M group and 102 cases out of 250 in L group. Average No. of child are 2.9 in Land 3.1 in M. (3) Concidering the operation day in the menstrml cycle, the greatest number of cases, those who underwent tubal sterilization during the days of $26{\sim}$, next during the $6{\sim}10$ days of the cycle in both group. (4) Concidering the operation time, 188 cases by laparoscopy were performed in $6{\sim}10$ minutes, 33 cases within 5 minutes and 24 cases in $11{\sim}15$ minutes. Maximum 50 minutes, minimum 4 minutes and average 8.3 minutes. The majority of cases (154 cases) by minilaparotomy required $6{\sim}10$ minutes and 67 cases $11{\sim}15$ minutes, 6 cases within 5 minutes. Maximum 30 minutes, minimum 4 minutes and average 10.4, minutes. In both groups, most of the reasons for the extra length were surgical difficulties such as thick abdominal wall, pelvic adhesion, less cooperation of patients in early period of this study. (5) Hospital stay after operation in L group required $3{\sim}4$ hours in 125 cases, $2{\sim}3$ hours in 41 cases, $4{\sim}5$ hours in 32 cases out of 250. Maximum 8 hours, minimum 1 hour and average 3.8 hours. In M group hospital stay required $6{\sim}7$ hours in 100 cases, over 7 hours in 85 cases, $5{\sim}6$ hours in 46 cases and so on. Maximum 14 hours, minimum 2 hours and average 6.5 hours. (6) The time between operation and gas passing in the majority cases of both groups, were $12{\sim}36$ hours. A veragetime 20.3 hours in L and 27.2 in M. (7) Laparoscopic sterilization coincident with induced abortion were carried out in 27 cases, laparoscopy with minilaparotomy to control for mesosalpingeal hemorrhage in 1 case. Minilaparotomy coincident with induced abortion were performed in 65 cases, D and C whit polypectomy, menstrual regulatian, and remaval of IUD in 1 case respectively. (8) In L group, 1 case of mesosalpingeal hemorrhage, 1 case of abdominal wall infection were complicated during operation. In M group, 1 case of uterine perfaration, 1 case of abdominal wall infection, 1 case of hemorrhage from omentum and 1 case of bloody vaginal discharge were complicated. No intensive medical treatment was required for those minor complications in both groups. (9) No failure has been recognized and these two sterilization techniques might be the simple, safe and the most effective method for permanent contraception at present time. There is no significant clinical defference between L and M group in this study.

• Journal of Korean Society of Forest Science
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• v.99 no.4
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• pp.611-617
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• 2010

The current studies aim is to analyze the production cost of walnut tree cultivation and its object was targeted at walnut tree cultivating household region 163. The analysis is as follows. Our domestic walnut tree cultivating households averagely have cultivated about 0.7ha, and planting number per ha was averagely 204, and it showed that compared to the standard planting number (100), the plantation was done close planted. The most cultivar cultivated according to regions were Chungbuk region: sangchon 65.7%, Chungnam region: kwangduk 68.6%, Jeonbuk region: sangchon 98.0%, Gyeongbuk region: daeboo 61.2%. The production cost for cultivating walnuts can be classified into the followings; management cost(4436 thousand won/ha) such as manufacturing cost(292 thousand won/ha), intermediate material cost(3682 thousand won/ha), rent(103 thousand won/ha), employment cost(653 thousand won/ha) etc, and self-serviced expenses such as self-laboring cost(5,834 thousand won/ha), land security cost(490 thousand won/ha), fixed capital cost(834 thousand won/ha), circulating capital cost(234 thousand won/ha) etc. 11,820 thousand won were invested for the production cost of walnut and it made 11,586 thousand won/ha(rate of investment 72.3%) profit, and the net income was 4,196 thousand won/ha(net income rate 26.2%), showing high amount of income. The manufactured walnuts were marketed in Nong-hyup 39.8%, wholesalers 20.8%, dealers 19.8% and recently, as the amount of goods marketed directly to consumers themselves have increased, the income has reached up to 18.9%. At the basis of making most of idle soil, walnut tree's cultivated regions are fairly small, and due to the characteristics of sideline management, it has its limits in searching for production policy locally and promotion strategy of industries. Therefore, if the basic database can be established, subjected only to full-time cultivating households, then not only would the differences between the imported walnuts be reinforced, it would also be possible to transfer into the new and improved distribution system. Furthermore, through establishment of the database, it can be anticipated that it would contribute greatly in the increase of the household income.

• KDI Journal of Economic Policy
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• v.12 no.2
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• pp.95-120
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• 1990

The underpricing of new shares of a firm that are offered to the public for the first time (initial offerings) is well known and has puzzled financial economists for a long time since it seems at odds with the optimal behavior of the owners of issuing firms. Past attempts by financial economists to explain this phenomenon have not been successful in the sense that the explanations given by them are either inconsistent with the equilibrium theory or implausible. Approaches by such authors as Welch or Allen and Faulhaber are no exceptions. In this paper, we develop a signalling model of capital investment to explain the underpricing phenomenon and also analyze the efficiency of investment. The model focuses on the information asymmetry between the owners of issuing firms and general investors. We consider a firm that has been owned and operated by a single owner and that has a profitable project but has no capital to develop it. The profit from the project depends on the capital invested in the project as well as a profitability parameter. The model also assumes that the financial market is represented by a single investor who maximizes the expected wealth. The owner has superior information as to the value of the firm to investors in the sense that it knows the true value of the parameter while investors have only a probability distribution about the parameter. The owner offers the representative investor a fraction of the ownership of the firm in return for a certain amount of investment in the firm. This offer condition is equivalent to the usual offer condition consisting of the number of issues to sell and the unit price of a share. Thus, the model is a signalling game. Using Kreps' criterion as the solution concept, we obtained an essentially unique separating equilibrium offer condition. Analysis of this separating equilibrium shows that the owner of the firm with high profitability chooses an offer condition that raises an amount of capital that is short of the amount that maximizes the potential profit from the project. It also reveals that the fraction of the ownership of the firm that the representative investor receives from the owner of the highly profitable firm in return for its investment has a value that exceeds the investment. In other words, the initial offering in the model is underpriced when the profitability of the firm is high. The source of underpricing and underinvestment is the signalling activity by the owner of the highly profitable firm who attempts to convince investors that his firm has a highly profitable project by choosing an offer condition that cannot be imitated by the owner of a firm with low profitability. Thus, we obtained two main results. First, underpricing is a result of a signalling activity by the owner of a firm with high profitability when there exists information asymmetry between the owner of the issuing firm and investors. Second, such information asymmetry also leads to underinvestment in a highly profitable project. Those results clearly show the underpricing entails underinvestment and that information asymmetry leads to a social cost as well as a private cost. The above results are quite general in the sense that they are based upon a neoclassical profit function and full rationality of economic agents. We believe that the results of this paper can be used as a basis for further research on the capital investment process. For instance, one can view the results of this paper as a subgame equilibrium in a larger game in which a firm chooses among diverse ways to raise capital. In addition, the method used in this paper can be used in analyzing a wide range of problems arising from information asymmetry that the Korean financial market faces.

• Journal of the Korea institute for structural maintenance and inspection
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• v.22 no.6
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• pp.53-62
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• 2018

Follofwing the accelerating speed-up of trains and rising demand for large-volume transfer capacity, not only in Korea, but also around the world, track structures for trains have been improving consistently. Precast concrete slab track (PST), a concrete structure track, was developed as a system that can fulfil new safety and economic requirements for railroad traffic. The purpose of this study is to provide the information required for the development and design of the system in the future, by analyzing the behavior of each structural member of the PST system. The stress distribution result for different combinations of appropriate loads according to the KRL-2012 train load and KRC code was analyzed by conducting a three-dimensional finite element analysis, while the result for different thicknesses of the grouting layer is also presented. Among the structural members, the largest stress took place on the grouting layer. The stress changed sensitively following the thickness and the combination of loads. When compared with a case of applying only a vertical KRL-2012 load, the stress increased by 3.3 times and 14.1 times on a concrete panel and HSB, respectively, from the starting load and temperature load. When the thickness of the grouting layer increased from 20 mm to 80 mm, the stress generated on the concrete panel decreased by 4%, while the stress increased by 24% on the grouting layer. As for the cracking condition, tension cracking was caused locally on the grouting layer. Such a result indicates that more attention should be paid to the flexure and tension behavior from horizontal loads rather than from vertical loads when developing PST systems. In addition, the safety of each structural member must be ensured by maintaining the thickness of the grouting layer at 40 mm or more.

• Journal of the Korean association of regional geographers
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• v.6 no.2
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• pp.83-96
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• 2000

Erosional basins formed in middle and upper reaches of Korean great rivers have been main life space of local small and middle cities, but previous studies on erosional basins are widely apart from residents' life and are in shortage with the endeavor to elucidate the man and environment relationship. This paper analyzes the factors and the modes of land-use changes of hills in the erosional basin. In this paper four erosional basins with different geological conditions are selected to elucidate the effect of geological factor(Geochang: granite, Chogye: metamorphic rock, Angye: gravelly sedimentary rock, Maseong: limestone). And the distribution of land use on the transverse and longitudinal cross-section map of the hill is described. The landscape of erosional basin is consisted of surrounding mountains, hills, dissected valleys, and incoming river's floodplain. Dissected valleys and incoming river's floodplain were reclaimed early as paddy field and hills have been used as woodland up to recently. Residents have a new appreciation of hills as a productive hill out of a traditional holy space[mountain] by influence of capitalistic thought that 'natural environment is a sort of productive resource'. Population increase is the another pressure of hill reclamation. The modes of landscape changes due to natural conditions are as follow: (1) In Geochang basin with dense tectolineament spacing, the gentle part of hill is used as field, orchard and agricultural-industrial complex site and the steep part is as woodland. (2) Hills in Angye basin with sparse tectolineament spacing are relatively flat because of maintaining a part of original denudational surface, and are used as orchids, field, paddy fields and agricultural-industrial complex site. The dissection valleys between hills are gentle concave and are used as paddy fields. (3) Hills in Maseong basin are wide and flat, and are used as fields, orchards, and agricultural-industrial complex site. (4) Because hills in Chogye basin, a closed type, are weared by affluents and are narrow and short. Hills are used as woodland and wide dissected valleys are reclaimed as paddy fields.

• The Journal of Engineering Geology
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• v.14 no.1
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• pp.29-46
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• 2004

It is important to identify geometries of fracture that act as a conduit of fluid flow for characterization of ground water flow in fractured rock. Fracture geometries control hydraulic conductivity and stream lines in a rock mass. However, we have difficulties to acquire whole geometric data of fractures in a field scale because of discontinuous distribution of outcrops and impossibility of continuous collecting of subsurface data. Therefore, it is needed to develop a method to describe whole feature of a target fracture geometry. This study suggests a new approach to develop a method to characterize on the whole feature of a target fracture geometry based on the Fourier transform. After sampling of specimens along a target fracture from borehole cores, effective frequencies among roughness components were selected by the Fourier transform on each specimen. Then, the selected effective frequencies were averaged on each frequency. Because the averaged spectrum includes all the frequency profiles of each specimen, it shows the representative components of the fracture roughness of the target fracture. The inverse Fourier transform is conducted to reconstruct an averaged whole roughness feature after low pass filtering. The reconstructed roughness feature also shows the representative roughness of the target subsurface fracture including the geometrical characteristics of each specimen. It also means that overall roughness feature by scaling up of a fracture. In order to identify the characteristics of permeability coefficients along the target fracture, fracture models were constructed based on the reconstructed roughness feature. The computation of permeability coefficient was performed by the homogenization analysis that can calculate accurate permeability coefficients with full consideration of fracture geometry. The results show a range between $10^{-4}{\;}and{\;}10^{-3}{\;}cm/sec$, indicating reasonable values of permeability coefficient along a large fracture. This approach will be effectively applied to the analysis of permeability characteristics along a large fracture as well as identification of the whole feature of a fracture in a field scale.

• Korean Journal of Soil Science and Fertilizer
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• v.6 no.2
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• pp.75-81
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• 1973

The morphological, physical, and chemical properties of Sonjeong series derived from acidic crystalline rocks are presented. Also it deals with the genesis and classification of the Songjeong series. Morphologically these soils have brown to dark brown loam A horizons and yellowish red to red clay loam Bt horizons with moderate, medium subangular blocky structure and thin patchy clay cutans on the ped faces. C horizons are very deep, yellowish red to yellowish brown fine sandy loam or sandy loam with original rock structure. Physically distribution of particle size indicates that clay increases with depth up to argillic horizons but below the argillic horizons clay content decrease. The moisture holding capacity is fairly good in Songjeong soils. Chemically soil reaction is strongly to very strongly acid throughout the profile and content of organic matter is less than 1 per cent except A horizons. Cation exchange capacity ranges from 5 to 9 me/100g of soils and base saturation is less than 35 per cent throughout the profile. The natural fertility of Songjeong soils are usually low. It needs lime, organic matter, and heavy application of fertilizer for the crop land. These soils occur temperate and humid climate under coniferous, deciduous, and mixed forest vegetation. Songjeong soils are classified as Red-Yellow Soils. Characteristically Songjeong soils are similar to Red-Yellow Podzolic soils in the United States but lack of A2 horizons and are quite liket Red-Yellow Soils of the Japan. According to new classification system which is 7th approximation of USDA Songjeong soils can be classified as fine loamy, mesic family of Typic Hapludults and in the FAO/UNESCO project World Soil Map as Orthic Acrisols.

• Journal of Technology Innovation
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• v.17 no.2
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• pp.1-23
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• 2009

The Survey on the Industrial Research and Development(R&D) is the primary source of information on R&D performed by Korea industrial sector. The results of the survey are used to assess trends in R&D expenditures. Government agencies, corporations, and research organizations use the data to investigate productivity determinants, formulate tax policy, and compare individual company performance with industry averages. Recently, Korea Industrial Technology Association(KOITA) has collected the data by complete enumeration. Koita has, currently, considered sample survey because the number of R&D institutions in industry has been dramatically increased. This study develops survey design for the industrial research and development(R&D) statistics by introducing a sample survey. Companies are divided into 8 groups according to the amount of R&D expenditures and firm size or type. We collect the sample from 24 or 8 sampling strata and compare the results with those of complete enumeration survey. The estimates from 24 sampling strata are not significantly different to the results of complete enumeration survey. We propose the survey design as follows: Companies are divided into 11 groups including the companies of which R&D expenditures are unknown. All large companies are included in the survey and medium and small companies are sampled from 70% and 3%. Simple random sampling (SRS) is applied to the small company partition since they show uniform distribution in R&D expenditures. The independent probability proportionate to size (PPS) sampling procedure may be applied to those companies identified as 'not R&D performers'. When respondents do not provide the requested information, estimates for the missing data are made using imputation algorithms. In the future study, new key variables should be developed in survey questionnaires.

• Pediatric Infection and Vaccine
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• v.16 no.1
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• pp.31-39
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• 2009

Purpose : Neisseria meningitides is one of the most common causative pathogens of bacteremia and meningitis. Recently protein-conjugated vaccines have been developed and included in the routine vaccination schedule in a few countries. In Korea, carriage rates of N. meningitides among healthy adults have been reported. However, systematic data for childhood carriage rates are not available. This study was performed to evaluate the carriage rates of N. meningitides and the serotype distribution among healthy children attending day care centers. Methods : During the period of January through May 2005, nasopharyngeal swabs and culture were obtained from 904 children attending 13 different day care centers located in Seoul and Gyeonggi Province. The Vitek NHI card was used to identify N. meningitides and the crgA gene was detected via polymerase chain reaction (PCR). Serotype determination was performed by agglutination test using N. meningitides antisera to serotypes A, B, C, D, 29E, W135, X, Y, and Z. PCR for detection of the org2 and saiD gene confirmed serotypes A, B, C, W135, and Y. Results : The mean age among 904 children was 4.5 years; 6.5% (59/904) were children <2 years old, 53.8% (486/904) were 2-5 years old, and 39.7% (359/904) were >5 years old; 52.0% (468/904) were male. N. meningitides was isolated from only 7 children attending 5 different day care centers and the overall carriage rate of N. meningitides was 0.8%. The detected serotypes of N. meningitides were serotype A (n=2), C (n=2), and Y (n=3). Conclusion : The carriage rate of N. meningitides among healthy children attending day care centers was very low in Korea and the detected serotypes were A, C, and Y.

• The Journal of Korean Society for Radiation Therapy
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• v.30 no.1_2
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• pp.17-25
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• 2018

Purpose : To compare the radiation doses of prostate cancer patients according to changes in abdominal body shape and energy during Volumetric modulated arc therapy(VMAT). Materials and Methods : Seven patients with prostate cancer were enrolled in this study. VMAT treatment plan was established at 6, 10, and 15 MV while changing from -2.0 cm to 2 cm by 0.5 cm. Conformal index(CI), homogeneous index(HI), $D_{max}$, $D_{95%}$, $D_{50%}$ and $D_{2%}$ of PTV were examined in order to evaluate the change of dose in the target organ according to body shape change. Normal organ of the femoral head, rectum and bladder was analyzed to evaluate dose changes. Results : The dose of $D_{max}$ 6 MV in PTV increased to 107.2 % in 1.0 cm body shape reduction, and 10 MV and 15 MV dose increased to 107.1 % and 107.0 % in 1.5 cm body reduction, respectively. The dose of $D_{50%}$ 6 MV in PTV decreased to 99.64 % in 1.0 cm body shape increase, and in 10 MV and 15 MV dose decreased to 99.79 % and 99.97 % in 1.5 cm body increase, respectively. In 2.0 cm body type increase, the dose was decreased to 99.30 % and 99.52 %, respectively. Doses for rectum and bladder gradually increased with decreasing weight, and dose decreased with decreasing weight. 6 MV, and $V_{70Gy}$ at 10 MV increased from 11.50 % to 12.76 % when the external shape decreased by 2.0 cm. The bladder $V_{70Gy}$ also increased from 14.0 % to 15.2 %. It was also shown that the dose increased as the body weight decreased in the femoral head. Conclusion : In the treatment of VMAT, dose distribution can be changed according to the change of abdominal shape. SSD and CBCT were used to decrease the body shape by more than 1cm or more than 1.0 cm at 6 MV and the body shape by more than 1.5 cm or more than 1.5 cm at 10 MV or 15 MV. It is considered that a new treatment plan should be established through re-simulation.