• 한국지반환경공학회 논문집
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• 제3권2호
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• pp.23-33
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• 2002

산업부산물인 제지회의 연약지반 표층고화처리 등을 목적으로 하는 지반개량재로써의 활용가능성을 모색하였다. 100% 제지회와 강도증진 등을 위한 2차 첨가재로써 시멘트 및 소량의 황산염(sulfate)성분을 첨가한 각각의 제지회 혼합토에 대하여 일축압축강도, 전자주사현미경관찰, pH분석 등을 수행하였다. 모든 경우에 있어서 양생이 진행됨에 따라서, 혼합비의 증가에 따라서, 혼합토의 강도는 증가하나 혼합초기에 거의 대부분의 강도가 발현되며 강도증가 효율면에서는 흙과의 혼합비가 9% 내외에서 최대 효율을 나타낸다. 제지회만을 사용하는 경우에 비하여 제지회에 함유된 시멘트량이 10~30%까지는 약 2배의 강도가 증가하며 시멘트 함유량이 40%일 경우에는 5~8배 정도 강도가 증가한다. 포졸란 반응 및 수화물의 생성에 유리한 환경을 나타내는 조건은 시멘트 함유량이 20%이상의 제지회를 7%이상 흙과 혼합했을 경우이다. 제지회만을 사용하는 경우에는 수화반응 또는 포졸란 반응이 활발하지 못하며, 흙과의 혼합비가 10% 이상에서 활발하게 유산석회수화물이 생성된다.

• 한국응급구조학회지
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• 제13권2호
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• pp.87-98
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• 2009

Purpose : This study set out to compare the educational effects of a video self-instruction program for child CPR education on childcare teachers by applying the 2006 KACPR Guideline. By adopting the nonequivalent control group posttest quasi-experimental design, the study examined the educational effects on a group that did not receive instructions from the instructor, another group that received his instructions, and the other group that received an extra three-minute practice training session in addition to instructions. Methods : Data were gathered from August 6 to 18, 2008. As for research tools, the Knowledge Instrument of CPR by Connolly (2006) was used along with the National Practice Test Protocol for C1ass 1 Emergency Medical Technicians (2007) and Common Protocol for CPR (2006) to examine the performance of child CPR. By shooting the guide screen of $Resusci^{(R)}$ Junior CPR Manikin of Leardal with a video camera and using the Skill Guide Checklist of the Common Protocol for CPR (2006), the subjects' technical accuracy of chi1d CPR was evaluated. There were three subject groups: 29 childcare teachers randomly assigned to received the video self-instruction program training for chi1d CPR and no instructions from the instructor made up the control group; 22 childcare teachers randomly assigned to received the program training and instructions from the instructor made up experiment group I; 23 childcare teachers randomly assigned to received an extra three-minute practice training session in addition to the program training and the instructions made up experiment group II. The gathered data were analyzed with SPSS/PC+ (Version 14.0) in frequency, percentage, $X^2$-test, ANOVA, Scheffe test. Results : 1) There were no statistically significant differences (F=1.030, p=.362) among the groups in terms of knowledge scores after the child CPR education. 2) There were statistically significant differences (F=13.625, p=.000) among the groups in terms of performance abilities after the child CPR education. 3) There were no statistically significant differences (F=1.610, p=.207) among the groups in terms of technical accuracy of mouth-to-mouth resuscitation after the child CPR education 4) There were no statistically significant differences (F=1.484, p=.234) among the groups in terms of technical accuracy of chest compression after the child CPR education. Conclusion : The results indicate that childcare teachers can improve their performance abilities in child CPR when the instructors are active with their instructions and extra practice hours are secured through a VSI program. It's also needed to provide education with increasing concentration ratio about the items of lower knowledge points in order to help the teachers learn the accurate theory of child CPR. And there should be VSI programs of diverse conditions to increase the effects of child CPR training among childcare teachers.

• Tuberculosis and Respiratory Diseases
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• 제79권4호
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• pp.267-273
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• 2016

Background: Cystic fibrosis (CF) is an autosomal recessive disorder with several clinical presentations. This study was undertaken in the Azeri Turkish population in Iran, to investigate gender differences in the age at onset and diagnosis, age of death, and duration of illness of CF. Methods: The data of 331 CF patients from 2001 to 2015 was surveyed. Parameters including age, sex, ${\Delta}F508$ mutation, age at onset, age at diagnosis, age of death and clinical presentations were evaluated for both sexes, using descriptive analysis. The association of gender with these variables was studied using logistic regression, chi-square test and Mann-Whitney U test by SPSS version 18. Odds ratio with a confidence interval of 95% and $p{\leq}0.05$ was considered statistically significant. Results: The study included 191 males (57.7%) and 140 females (42.3%), all showing statistically significant difference (p<0.001). Age duration differed between genders. Male and female patients were further under 9 and 4 years, respectively. The occurrence of ${\Delta}F508$ mutation was 0.51 times more in females than in males. Age, diagnosis and sex were closely associated: males were diagnosed at a significantly later age than females (p=0.05). While this compression performed based on clinical presentations, males with respiratory disease had a later median age at diagnosis than females at lifespan (p=0.001). The risk of infertility in males was approximately two times greater than in females (p=0.02). Conclusion: These findings indicate gender differences in CF patients. Future studies are needed to establish other differences and evaluate the causes for the gender variations.

• Journal of Preventive Medicine and Public Health
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• 제33권2호
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• pp.184-192
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• 2000

Objectives : To inquire the prevalence and the risk factors for myofascial pain syndrome (MPS) on young boys in order to use these results as the fundamental data for the prevention of their MPS. Methods : For 7 days in May 1999, this research was taken on 489 male students ranging from 6th to 12th grade. We randomly selected a class for every group and from these classes we operated physical examinations, self-reported questionnaires and from a rehabilitation doctor, MPS test was taken. Thoracic kyphosis and lumbar lordosis were also taken by using the inclinometer. We defined MPS as a regional pain complaint, palpable taut band that is painful on compression. Results : The shoulder MPS prevalence of the subjects were 29.7 persons/100 persons. The statistics revealed that as grades went up, the percentage significantly increased in the MPS prevalence. As of case-control study, 145 students who were tested postive in all aspects were placed as cases, and 176 students who were perfectly normal as controls on risk factors. As a result of comparing the student groups who were stisfied with their chairs to the student groups were not satisfied, the taller showed a significantly higher odds ratio (p<0.01). By the multiple logistic regression test, we concluded that the MPS disease was prevailed far more in the students in the higher grades (Odds ratio: 1.16, 95% C.I.: 1.03-1.31), and also those who were dissatisfied with their chairs than in the ones who were satisfied (Odds ratio: 1.92, 95% C.I.: 1.17-3.17). Conclusions : Significant correlations showed between the MPS diagnosed group and the students who are dissatisfied with their chairs. As a result, more research and observation has to be made concerning this disease, and the desks and chairs should be adjusted to suit the student's physical standards.

• 대한의용생체공학회:의공학회지
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• 제31권1호
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• pp.56-66
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• 2010

The various total replacement artificial discs have developed because spinal fusion has shown a lesser mobility of an operated segment and an accelerated degeneration at adjacent discs. But almost artificial discs have not yet been reached on the substitute surgery of fusion because many problems such as those clinical success rates were not more than them of fusion have not solved. In this paper, vertically inserted assemble-screw fixture in vertebrae was proposed to improve the fixed capability of artificial disc. And also, to evaluate the design suitability of newly designed screw-type, including fixtures of commercial discs such as wedge and plate type, the 1/4 finite element model with a vertebra and various implanted fixtures were generated, and next, 3 bending motions such as flexion, bending and twisting under the moment of 10Nm and compression under the force of 1000N were considered, respectively and finally, FE analyses were performed. Results of three fixture types were compared, such as Range of Motion and maximal stress, and so on. For ROM, the screw type was average 58% less than the wedge type and was average 42% less than the plate type under all loading conditions. For average stress ratio at closer nodes between vertebra and each fixture, the wedge type was the lowest as minimum 0.02 in twisting, screw types were the highest as maximum 0.28 in compression. As the results of using cement material, it was predicted that the instability problem of the wedge type was better solved. The screw type which could be increased by implanting depth according to the number of assembling mid screws, showed that the decreased tendency of ROMs and maximal cancellous bone stresses. In further study, controlling the number of assembling screws that was suitable for a patient's bone quality, development of surgical tools and keeping on design supplementations, which will be able to develop the competitive artificial disc.

• Journal of Korean Neurosurgical Society
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• 제54권2호
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• pp.112-117
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• 2013

Objective : We performed this study to investigate whether the use of closed-suction drainage following microvascular decompression (MVD) causes cerebrospinal fluid (CSF) leakage. Methods : Between 2004 and 2011, a total of 157 patients with neurovascular compression were treated with MVD. MVD was performed for hemifacial spasm in 150 (95.5%) cases and for trigeminal neuralgia in 7 (4.5%) cases. The mean age of the patients was $49.8{\pm}9.6$ years (range, 20-69). Dural substitutes were used in 44 (28.0%) patients. Ninety-two patients (58.6%) were underwent a 4-5 cm craniotomy using drainage (drainage group), and 65 (41.4%) did a small 2-2.5 cm retromastoid craniectomy without closed-suction drainage (no-drainage group). Results : Eleven (7.0%) patients experienced CSF leakage following MVD based on the criteria of this study; all of these patients were in the drainage group. In the unadjusted analyses, the incidence of CSF leakage was significantly related with the use of closed-suction drainage following MVD (12.0% in the drainage group vs. 0% in the no-drainage group, respectively; p=0.003; Fisher's exact test). Those who received dural substitutes and the elderly (cut-off value=60 years) exhibited a tendency to develop CSF leakage (p=0.075 and p=0.090, respectively; Fisher's exact test). In the multivariate analysis, only the use of closed-suction drainage was significantly and independently associated with the development of CSF leakage following MVD (odds ratio=9.900; 95% confidence interval, 1.418 to infinity; p=0.017). Conclusion : The use of closed-suction drainage following MVD appears to be related to the development of CSF leakage.

• Journal of Acupuncture Research
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• 제24권2호
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• pp.155-167
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• 2007

Objectives : This study was performed to evaluate the general distribution and the efficacy of oriental medical treatment for low back pain. Methods: We have selected of the moxa bucket moxibustion. We make a comparative study of the thermodynamic characteristics of moxa bucket moxibustion. We examined combustion times, temperatures, temperature gradients in each period during a combustion of moxa bucket moxibustion made by oak wood. Results : The 80 cases of low back pain patients was analyzed according to the distribution of sex, age, the period of disease, contributing factor, the patient-condition on admission, the symptom on admission, the duration of admission, the reading of the X-ray and the treatment efficacy was evaluated respectively. 1. Female was more than male in the ratio of 1:1.2, and thirties and seventies 25% the most, the acutest phase 46.3% the most, reason unknown 33.8% the most, Grade III 50% the most, L.B.P. only 51.3% the most, the day of 6-10 30% the most, compression Fx 30% the most. 2. In the total treatment result, the good was 51.3%, the excellent 22.5%, the fair 17.5%, the poor 8.8% in order. About 'the effective rate'(the percentage of positive effective treatment cases) of each distribution, the fifties 100% the most, the acutest phase 97.3% the most, the slip down, weight lifting, overuse 100% the most respectively, Grade III 97.5% the most, L.B.P. only 95.1% the most, the day of 11-15 100% the most, HN.P. 93.3% the most. Conclusions : We have known the efficacy of oriental medical treatment for L.B.P. was good and early treatment was better than late treatment and main cause of L.B.P. was degenerative change.

• Steel and Composite Structures
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• 제31권6호
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• pp.601-615
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• 2019

In cold-formed steel (CFS) structures, such as trusses, wall frames and columns, the use of back-to-back built-up CFS angle sections are becoming increasingly popular. In such an arrangement, intermediate fasteners are required at discrete points along the length, preventing the angle-sections from buckling independently. Limited research is available in the literature on the axial strength of back-to-back built-up CFS angle sections. The issue is addressed herein. This paper presents the results of 16 experimental tests, conducted on back-to-back built-up CFS screw fastened angle sections under axial compression. A nonlinear finite element model is then described, which includes material non-linearity, geometric imperfections and explicit modelling of the intermediate fasteners. The finite element model was validated against the experimental test results. The validated finite element model was then used for the purpose of a parametric study comprising 66 models. The effect of fastener spacing on axial strength was investigated. Four different cross-sections and two different thicknesses were analyzed in the parametric study, varying the slenderness ratio of the built-up columns from 20 to 120. Axial strengths obtained from the experimental tests and finite element analysis were used to assess the performance of the current design guidelines as per the Direct Strength Method (DSM); obtained comparison showed that the DSM is over-conservative by 13% on average. This paper has therefore proposed improved design rules for the DSM and verified their accuracy against the finite element and test results of back-to-back built-up CFS angle sections under axial compression.

• 한국전자파학회논문지
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• 제25권1호
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• pp.53-61
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• 2014

본 논문에서는 고조파 정합 기법을 이용하여 고효율 GaN HEMT 전력 증폭기를 설계 및 제작하고, 그 특성을 측정하였다. 고효율 특성을 얻기 위해 고조파 로드풀 시뮬레이션을 활용하였다. 즉, 기본 주파수뿐만 아니라 2차, 3차 등의 고조파에서 최적의 부하 임피던스를 찾아내었다. 이러한 고조파 로드풀 시뮬레이션 결과를 바탕으로 출력 정합 회로를 설계하였다. 제작한 전력 증폭기는 중심 주파수 1.85 GHz에서 선형 전력 이득 20 dB 및 33.7 dBm의 $P_{1dB}$(1 dB gain compression point) 특성을 보였다. 그리고, 출력 전력 38.6 dBm에서 80.9 %의 최대 전력 부가 효율(Power Added Efficiency: PAE)을 나타냈으며, 이는 기존에 설계된 고효율 전력 증폭기와 비교했을 때 아주 우수한 효율 특성이다. 또한, W-CDMA 신호입력에 대한 측정 결과, 28.4 dBm의 평균 출력 전력에서 27.8 %의 PAE와 5 MHz offset 주파수에서 -38.8 dBc의 ACLR (Adjacent Channel Leakage Ratio)을 보였다. 그리고, 다항식 맞춤 방식의 디지털 전치 왜곡(Digital Predistortion: DPD) 선형화 알고리듬을 구현하여 제작된 전력 증폭기의 ACLR을 6.2 dB 정도 향상시킬 수 있었다.

• 대한한방체열의학회지
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• 제1권1호
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• pp.28-37
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• 2002

Stable Compression Fractures(SCF hereafter) are most often caused by trauma such as traffic accidents. These SCFs usually occur in the thoracic and lumbar regions of the spinal cord. Human life spans have increased as a result of medical advances, which in turn has led to an increase in the elderly population. SCFs are divided into the categories of stable and unstable. The categories are determined through X-rays and P/Ex tests. The D.I.T.I. is then used to diagnose the severity and prognosis of the fracture injuries, and it allows an objective evaluation of the symptoms. This author researched 40 patients who were treated at Wonkwang University Oriental Medical Center from October 1995 to December 1996. The patients were diagnosed by X-ray as having SCFs and treated primarily with acupuncture. Both the changes in D.I.T.I. and patients' self-diagnoses of their conditions before and after treatment yielded the meaningful results which have been presented here. 1. 75% of those who suffer from Stable Compression Fractures are 60 years of older. Of those, the ratio of male to female is 1 to 4. This is due in part to the fact that many elderly women seek Oriental medicine treatment for conditions associated with advanced age. 2. 53.3% of these injuries occurred between T11 and L2. 3. 65% of patients were hospitalized for 10 to 29 days, and then able to be treated on an outpatiens basis. 4. The D.I.T.I. results showed 50% below $0.2^{\circ}C$, 30% between 0.3 and $0.5^{\circ}C$, 10% between 0.5 and $0.7^{\circ}C$, 10% between 0.7 and $0.9^{\circ}C$, and 0% over $0.9^{\circ}C$. 5. The results of treatment using Modified Evaluation System in Thoracolumbar Vertebral Fractures Method showed that 55% of patients achieved excellent recovery and 40% achived good recovery. After comparing the D.I.T.I. results before and after treatment, we found 50% of patients showed excellent recovery $({\Delta}T{\leq}0.2)$ and 40% showed good recovery$(0.2<{\Delta}T{\leq}0.5)$.