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Geological Structure and Deformation History in the Gwangju area, Gyeonggi-do, Korea (경기도 광주시 일대의 지질구조와 변형사)

  • Lee Hee-Kwon;Kim Man-Kwang
    • The Journal of the Petrological Society of Korea
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    • v.14 no.2 s.40
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    • pp.108-115
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    • 2005
  • Gyeonggi metamorphic complex in the Gwangju area include banded biotite gneiss and quartzofeldspathic gneiss. Detailed structural analysis suggests that structural elements in the study area were formed by at least five phase of deformations. Penetrative compositional foliations(S1) formed in the banded gneiss during the first metamorphism and deformation (D1). After intrusion of plutonic rocks, the second deformation (D2) produced S2 foliations in the banded gneiss and quartzofeldspathic gneiss during the second metamorphism. D3 structures are represented by isoclinal folds (F3) whose axial surfaces are parallel to S3 foliations. The N-S oriented shortening (D4) was accommodated by closed upright F4 fold with about 100m of axial surface separation. F4 fold is refolded by regional F5 folding resulting in different orientation and fold style of F4 fold according to the position of F5 fold. The F4 fold with tight interlimb angle is subparallel to the axial surface (north-south) of F5 fold in the core of the F5 fold. In contrast the F4 fold trends northeast in the western limb and northwest in the eastern limb of F5 fold. The interlimb angle is larger in the limbs than that in the core of F5 fold. The trace of foliations is constrained by mainly F4 and F5 folds. Joint fanning around fold is developed in the limbs of F5 fold and bc joints are dominant in the hinge area of F5 fold. A strike-slip fault had developed in tile central part of the study area after F5 folding. The orientation of joint and foliation is rotated anticlockwise about $15^{\circ}$ by the landslide occurred during the Quaternary.

Applied Petrologic Study of the Daebo Biotite Granites in the mid Gyeonggi Massif (경기육괴 중부에 분포하는 대보 흑운모화강암류의 응용암석학적 연구)

  • Yun, Hyun-Soo;Hong, Sei-Sun;Park, Deok-Won;Lee, Jin-Young
    • The Journal of the Petrological Society of Korea
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    • v.21 no.2
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    • pp.263-275
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    • 2012
  • Jurassic Daebo biotite granites, known as one of the main stone resources in the country, are widely and away distributed in the Pocheon and Yangju areas of the mid Gyeonggi massif. The objects of the study are mainly to reveal the unique characteristics of grain size, rock color, mineral composition, physical property and fracture system from the above biotite granites. Biotite granites from the Pocheon area (PG) and Yangju area (YG) are represented by coarse-grained and light gray, and medium to coarse-grained and grayish to light gray, respectively. In modes, main minerals of Qz+Af+Pl (quartz+alkali feldspar+plagioclase) are more increased in the PG, and accessories of biotite are more increased in the YG, which differences can cause the PG more bright light gray than the YG. Specific gravity (SG) shows somewhat more increasing in the YG than the PG. These differences can be caused by more increasing in biotite contents of higher specific gravity compared to the major minerals in the former than the latter. Absorption ratio (AR) and porosity (PR) of the PG and YG show the same values of 0.33 % and 0.86 %, respectively. In the correlations, PR vs SG and AR vs PR show gradually negative and distinctly positive trends, respectively. Compressive strength (CS) and tensile strength (TS) show increasing in the PG (CS: 1,775 $kg/cm^2$, TS: 87 $kg/cm^2$) than the YG (CS: 1,647 $kg/cm^2$, TS: 79 $kg/cm^2$). These strength characteristics could be attributed to the inherent rock textures of them. Abrasive hardness (AH) also shows a little increasing in PG, which can be caused by increase in quartz contents having higher hardness than the other major minerals. Orientations of fracture sets from the PG and YG were compared with those of vertical rift and grain planes in Mesozoic granites of the country. From the overlapped diagram, the distribution pattern between fracture sets and above vertical planes suggests that microcrack systems developed in Mesozoic granites in Korea occur also in the Daebo biotite granite bodies of the mid Gyeonggi massif. From the relation diagram showing the characteristics of fracture patterns for the above two area, PG and YG may have more potentiality for dimension and non-dimension stone resources, respectively.

A Study on Load-carrying Capacity Design Criteria of Jack-up Rigs under Environmental Loading Conditions (환경하중을 고려한 Jack-up rig의 내하력 설계 기준에 대한 연구)

  • Park, Joo Shin;Ha, Yeon Chul;Seo, Jung Kwan
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.26 no.1
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    • pp.103-113
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    • 2020
  • Jack-up drilling rigs are widely used in the offshore oil and gas exploration industry. Although originally designed for use in shallow waters, trends in the energy industry have led to a growing demand for their use in deep sea and harsh environmental conditions. To extend the operating range of jack-up units, their design must be based on reliable analysis while eliminating excessive conservatism. In current industrial practice, jack-up drilling rigs are designed using the working(or allowable) stress design (WSD) method. Recently, classifications have been developed for specific regulations based on the load and resistance factor design (LRFD) method, which emphasises the reliability of the methods. This statistical method utilises the concept of limit state design and uses factored loads and resistance factors to account for uncertainly in the loads and computed strength of the leg components in a jack-up drilling rig. The key differences between the LRFD method and the WSD method must be identified to enable appropriate use of the LRFD method for designing jack-up rigs. Therefore, the aim of this study is to compare and quantitatively investigate the differences between actual jack-up lattice leg structures, which are designed by the WSD and LRFD methods, and subject to different environmental load-to-dead-load ratios, thereby delineating the load-to-capacity ratios of rigs designed using theses methods under these different enviromental conditions. The comparative results are significantly advantageous in the leg design of jack-up rigs, and determine that the jack-up rigs designed using the WSD and LRFD methods with UC values differ by approximately 31 % with respect to the API-RP code basis. It can be observed that the LRFD design method is more advantageous to structure optimization compared to the WSD method.

A Study on Formulation of Surfactant-free Aqueous Cleaning agents and Evaluation of Their Physical Properties and Cleaning Ability (계면활성제 무첨가 세정제의 배합 및 물성/세정성 평가 연구)

  • Lee, Jae Ryoung;Yoon, Hee Keun;Lee, Min Jae;Bae, Jae Heum;Bae, Soo Jeong;Lee, Ho Yeoul;Kim, Jong Hee
    • Clean Technology
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    • v.19 no.3
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    • pp.219-225
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    • 2013
  • Environment-friendly and surfactant-free aqueous cleaning agents have been developed in order to solve various problems generated by surfactants in the aqueous cleaning agents. Aqueous surfactant-free cleaning agents, S-1 and S-2 have been formulated with water-soluble solvents such as propylene glycol and propylene glycol ether on their main components and with some additives. These solvents were chosen because of their good solubility in water and excellent solubility of fluxes which are major contaminants of printed circuit board in the electronic industry. Physical properties of the formulated and the imported cleaning agents were measured to predict their cleaning performance, and their cleaning abilities of flux and solder contaminants were evaluated under the various ultrasonic frequencies by a gravimetric method. The measurement results show that the physical properties of cleaning agent V are generally similar with those of formulated cleaning agents S-1 and S-2. Both the cleaning agent V and the formulated cleaning agents S-1 and S-2 showed similar trends that their pH decrease in the beginning and then increases later on with the increase of their dilution in water. It is considered that the wetting indices of the cleaning agents calculated with experimental values do not not have any influence on their cleaning ability. In ultrasonic cleaning tests under three ultrasonic frequencies of 28, 45, and 100 kHz, their best performances of cleaning solder and flux were obtained at 45 kHz and 28 kHz, respectively, and the cleaning performance of the formulated cleaning agents S-1 and S-2 was better than that of the cleaning agent V. However, in the case of the recommended diluted concentration of 25 wt% cleaning solution, the cleaning performance of the cleaner V for solder and flux was better in the initial stage of cleaning compared to the formulated cleaners. And it may be concluded that the formulated cleaning agents S-1 and S-2 can be applied to cleaning of solder and flux in the industry, based on the experimental results in this study.

A Study on the Nurse's Due Care in Medical Malpractice (의료과오시(醫療過誤時) 간호사의(看護師)의 주의의무(注意義務)에 관한 연구(硏究))

  • Kang, Sun-Joo
    • Journal of Korean Academy of Nursing Administration
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    • v.5 no.1
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    • pp.113-136
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    • 1999
  • There are some new trends in judgments concerning medical malpractice. which include emphasis on medical professionals' explanation duty in order to materialize patient's rights of self-determination. Now, patient is not a mere subject of medical and nursing care any more, but a subject, participating in medical practice on equal terms with medical professionals. Legal accountability is no limited to nurses in advanced practice: it is a recognized fact of life for every practicing nurse. whether she is an RN employed as a staff nurse in a hospital, a Certified Nurse-Midwife in independent practice or a patient's home. Therefore, it is essential for nurses to be as familiar as possible with the legal guidelines that govern their patient care responsibilities. However there are only a few studies focused on nursing negligence. To define nurse's civil liability in medical malpractice, it is necessary to indentify both legal nursing behaviors and nurse's due care in those nursing behaviors. So this paper focused on nurse's due care, especially in nursing malpractice. To clarify nurses' due care. chapter II has focused on nursing behavior and the scope of nursing practice based on the medical law and health care related study results. Chapter III deals with the content and scope of nurse's due care. Generally. negligence is defined as not doing something which a resonable person. guided by those ordinary considerations which or dinarily regulate human affairs. would do. or doing something which a resonable and prudent man would not do. Next. it describes how we can set the standard of due care in nursing practice. There is objective factors and subjective factors. And we also discuss about the limitation of due care in nursing practice. Finally. chapter IV deals with the case studies related to nursing negligence in the situation of determination. Now', patient is not a mere subject of medical and nursing care any more, but a subject participating in medical practice on equal terms with medical professionals. Legal accountability is not limited to nurses in advanced practice; it is a recognized fact of life for every practicing nurse. whether she is an RN employed as a staff nurse in a hospital. a Certified Nurse-Midwife in independent practice or a patient's home. Therefore, it is essential for nurses to be as familiar as possible with the legal guidelines that govern their patient care responsibilities. However. there are only a few studies focused on nursing negligence. To define nurse's civil liability in medical malpractice, it is necessary to identify both legal nursing behaviors and nurse's due care in those nursing behaviors. So this paper focused on nurse's intravenous injection. post operation nursing care. blood transfusion. and patient nursing care. The result of this paper is as follows. First. there are several cases dealing with nurse's negligence in nursing practice. however, those cases didn't judge nurse's due care based on individual -specific standard but general-objective standard. Second, there is a tendency to put an emphasis on the principal of belief to distinguish who has the liability in the case of medical malpractice among medical care team. So nurses shoud practice nursing care more actively to protect themselves and patients because there is an effort to form professional nurse system and the scope of nursing practice will be deeper and broader. Third, standard of care is a necessary element in establishing negligence. If a nurse is able to meet the standard of care, no breach will be found.

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Optimal Spatial Scale for Land Use Change Modelling : A Case Study in a Savanna Landscape in Northern Ghana (지표피복변화 연구에서 최적의 공간스케일의 문제 : 가나 북부지역의 사바나 지역을 사례로)

  • Nick van de Giesen;Paul L. G. Vlek;Park Soo Jin
    • Journal of the Korean Geographical Society
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    • v.40 no.2 s.107
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    • pp.221-241
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    • 2005
  • Land Use and Land Cover Changes (LUCC) occur over a wide range of space and time scales, and involve complex natural, socio-economic, and institutional processes. Therefore, modelling and predicting LUCC demands an understanding of how various measured properties behave when considered at different scales. Understanding spatial and temporal variability of driving forces and constraints on LUCC is central to understanding the scaling issues. This paper aims to 1) assess the heterogeneity of land cover change processes over the landscape in northern Ghana, where intensification of agricultural activities has been the dominant land cover change process during the past 15 years, 2) characterise dominant land cover change mechanisms for various spatial scales, and 3) identify the optimal spatial scale for LUCC modelling in a savanna landscape. A multivariate statistical method was first applied to identify land cover change intensity (LCCI), using four time-sequenced NDVI images derived from LANDSAT scenes. Three proxy land use change predictors: distance from roads, distance from surface water bodies, and a terrain characterisation index, were regressed against the LCCI using a multi-scale hierarchical adaptive model to identify scale dependency and spatial heterogeneity of LUCC processes. High spatial associations between the LCCI and land use change predictors were mostly limited to moving windows smaller than 10$\times$10km. With increasing window size, LUCC processes within the window tend to be too diverse to establish clear trends, because changes in one part of the window are compensated elsewhere. This results in a reduced correlation between LCCI and land use change predictors at a coarser spatial extent. The spatial coverage of 5-l0km is incidentally equivalent to a village or community area in the study region. In order to reduce spatial variability of land use change processes for regional or national level LUCC modelling, we suggest that the village level is the optimal spatial investigation unit in this savanna landscape.

The Removal of Organics and Nitrogen with Step Feed Ratio Change into the Anoxic and Anaerobic reactor in Advanced Sewage Treatment process Using Nonsurface-modified and Surface-modified Media Biofilm (비개질/개질 생물막을 이용한 오수고도처리공정에서 혐기조와 무산소조의 원수 분배율에 따른 유기물 및 질소 제거)

  • Seon, Yong-Ho
    • KSBB Journal
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    • v.20 no.4
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    • pp.253-259
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    • 2005
  • This study was accomplished using attached $A^2/O$ process that contains nonsurface-modified and surface-modified polyethylene media inside the Anaerobic/Anoxic, Oxic tank, respectively. We could make the hydrophobic polyethylene media have hydrophilic characteristics by radiating ion beam on the surface of the media. The objectives of this study is to investigate the removal efficiencies of the organics and nitrogen when the step feed ratio of raw wastewater into anaerobic and anoxic tank is changed. In this case, we assumed that the denitrification rate can be improved because the nitrifiers in anoxic tank can perform denitrification using RBDCOD instead of artificial carbon sources (for example, methanol, etc.). The wastewater injection rate into anaerobic/anoxic tank was set up by the ratio of 10 : 0, 9 : 1, 8 : 2, 6 : 4, and the results of BOD removal efficiency showed similar trends with $93.3\%,\;92.6\%,\;92.4\%\;and\;91.6\%$, respectively. But the BOD removal efficiency (utilization of the organics) in the anoxic tank was in the order of 9 : 1 $(84.8\%)$, 10 : 0 $(77.0\%)$, 8 : 2 $(75.3\%)$, and 6 : 4 $(61.1\%)$. The T-N removal efficiency was most high when the ratio is 9 : 1 $(67.4\%)$, and other conditions, 10 : 0, 8 : 2, 6 : 4, showed $61.3(\%),\;60.7\%,\;55.5\%$, respectively; the ratio 6 : 4 was found to be lowest T-N removal efficiency, lower than the ratio 9 : 1 by $12\%$. Though the nitrification rate of the ratio 10 : 0, 9 : 1, and 8 : 2 showed similar levels, the ratio 6 : 4 showed considerable inhibition of nitrification, ammonia was the great portion of the effluent T-N. The advantages of this process is that this process is cost-saving, and non-toxic methods than injecting the artificial carbon source.

Serum Immunoglobulin levels in Coal Worker's Pneumoconiosis Patients (진폐증 환자에서의 혈청 면역 글로불린의 변화)

  • Yoo, Kwang-Ha;Ahn, Chul-Min;Kim, Hyung-Joong;Kim, Young-Ho;Lee, Yong-Kyoo;Kim, Sung-Kyu;Lee, Won-Young
    • Tuberculosis and Respiratory Diseases
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    • v.46 no.2
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    • pp.165-174
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    • 1999
  • Background: Coal-worker's pneumoconiosis(CWP) is radiologically divided into two major groups: simple pneumoconiosis (SP), in which small, rounded or irregular opacities smaller than 1cm are observed, and progressive massive fibrosis(PMF), which is characterized by opacities larger than 1cm. SP has a life expectancy equivalent to miners with no radiographic evidence of CWP, but PMF is associated with more obvious impairments of ventilatory capacity and premature death. But only minority of workers develop PMF when exposed to dust concentrations similar to those experienced by workers who develop only SP. In this study, immune status in patients with CWP were evaluated by measurement of the serum immunoglobulin levels between control, SP and PMF groups. Method: Coal workers selected for this study were emplyees of the Tae-Baek and Dong-Hae Hospital. All the patients were men of 45-76 years old and the mean duration of exposure to coal dust were 23.2 years. By X-ray examination, 51 patients were classified in SP, 59 in PMF category. The normal controls examined were 58 men of 26-70 years old. Serum Ig levels were estimated by using Nephelometer(Behring Nephelometer : Germany) and serum were collected 51 in SP, 49 in PMF and 57 cases in control group. Results: The levels of IgG were increased but the levels of IgM were decreased with increasing age in control groups. There were no statistical difference of immunoglobulin levels between smokers and nonsmokers in control groups. There were no statistical difference of immunoglobulin levels between Control, SP and PMF groups. Multiple regression analysis were undertaken to determine the statistical significance of the apparent trends and estimate the effects associated with age, smoking habit and radiological category of CWP. According to this analysis, the levels of IgG were decreased significantly in SP group and had decreasing tendancy, but not statistically significant in PMF group. Conclusion : From the observations described, CWP patients had decreased IgG concentration compared to control gorup. Therefore, there was some relation between CWP and immunoglobulin concentration.

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Comparative Study between Mathematically Gifted Elementary Students and Common Students in Self-Efficacy and Career Attitude Maturity (초등수학영재와 일반학생의 자기효능감과 진로태도성숙과의 관계 비교)

  • Lee, Jung Hwa;Ryu, Sung Rim
    • Communications of Mathematical Education
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    • v.27 no.1
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    • pp.63-80
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    • 2013
  • Reflecting the recent trends and needs of gifted education, this study set out to compare and analyze mathematically gifted elementary students and common students in self-efficacy and career attitude maturity, understand the characteristics of the former, and provide assistance for career education for both the groups. The subjects include 237 mathematically gifted elementary students and 221 common students in D Metropolitan City. The research findings were as follows: First, mathematically gifted elementary students turned out to have higher self-efficacy than common students at the significance level of .01 in the three self-efficacy subfactors, namely confidence, self-regulated efficacy, and task difficulty preference. The findings indicate that mathematically gifted elementary students have much confidence in themselves and strong faith in themselves, thus forming a habit of preferring a relatively high-level task by taking self-management and task difficulty into proper consideration. Second, mathematically gifted elementary students showed higher overall career attitude maturity than common students. There was significant difference at the significance level of .01 in decisiveness and preparedness between the two groups and significant difference at the significance level of .05 in assertiveness. However, there was no statistically significant difference in purposefulness and independence between the two groups. Finally, there were positive correlations at the significance level of .01 between all the subfactors of self-efficacy and those of career attitude maturity in all the subjects except for self-regulated efficacy and purposefulness, between which there were positive correlations at the significance level of .05. The mathematically gifted elementary students showed positive correlations between more subfactors of self-efficacy and career attitude maturity than common students. Given those findings, it is necessary to take differences in self-efficacy and career attitude maturity between mathematically gifted elementary students and common students into account when organizing and running a curriculum. The findings confirm the importance of providing students with various experiences fit for them and point to a need for helping mathematically gifted elementary students maintain a high level of self-efficacy and guiding them through career education with more appropriate career attitude maturity improvement programs.

Recent Trends in the Prevalence of Mycoplasma pneumoniae Pneumonia According to Age (연령에 따른 Mycoplasma pneumoniae 폐렴 발병의 최근 경향)

  • Lee, Hyo Sang;Choi, Kyong Min
    • Pediatric Infection and Vaccine
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    • v.15 no.2
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    • pp.162-166
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    • 2008
  • Purpose : It has been previously reported that for patients with Mycoplasma pneumoniae pneumonia was previously recognized that overt illness is unusual under the age of three and the peak incidence of illness occurs in school-aged children. However, a higher incidence of this illness in younger children has been recently noted. Thus we investigated the incidence of M. pneumoniae pneumonia. Methods : The study subjects were 414 children who were diagnosed with M. pneumoniae pneumonia from January 2004 to December 2006 at Myong Ji Hospital were enrolled. The diagnostic criteria consisted of an anti-mycoplasma antibody (AMA) titer greater than 1: 320 or a four-fold rise in the titer at follow up. Results : The age distribution was as follows: before 2 years of age: 58 patients (14%), 2-4 years of age 157 patients (37.9%) and 5-15 years of age 199 patients (48.1%). The yearly incidence for the children before 5 years of age was 52 (44%), 49 (44.6%) and 114 (61.3%), respectively. The distribution according to the antibody titer was as follows; 1: 320 in 130 patients, 1:640 in 63 patients and greater than 1:1,280 in 221 patients. The hospital stay according to the antibody titer was not significant according to either age or the AMA titers. Conclusion : M. pneumoniae pneumonia showed a peak incidence in preschool children with a higher prevalence in children under the age of three than was previously recognized. The emergence of M. pneumoniae pneumonia as a cause of community acquired pneumonia in younger children calls for an epidemiologic study to investigate the changes of the pathogens in this age group and to recommend the proper treatment.

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