• 구강회복응용과학지
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• 제21권2호
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• pp.95-103
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• 2005

Purpose: Recently, various metal primers have been developed, and these are known to increase the bond strength between metal and relining resin. In this study, the change in bond strength according to amount of thermocycling was evaluated. Materials and Methods: In this study, 216 specimens were fabricated. Tokuyama Rebase $II^{(R)}$(Tokuyama Corp., Japan) and $Kooliner^{(R)}$(GC America Inc., Japan) as relining material, and MR. $Bond^{(R)}$(Tokuyama Corp., Japan) and Alloy $Primer^{(R)}$(Kuraray Medical Inc., Japan) as a metal primers were used. Using Ni-Cr and various metal surface treatment methods, resin was bonded and the change in bond strength during thermocycling was measured. The data was analyzed by one-way ANOVA, t-test(p<.05 level of significance). Results: When comparing the groups with only sandblasting, rapid decrease in shear bond strength could be seen. In the groups using Tokuyama Rebase $II^{(R)}$, with the exception of the 1000 and 2000 cycle groups, each group showed statistically significant decrease in shear bond strength(p<0.05). In comparison according to relining materials, $Kooliner^{(R)}$ showed higher shear bond strength than Tokuyama Rebase $II^{(R)}$ in all groups. In groups using MR $bond^{(R)}$, $Kooliner^{(R)}$ had higher shear bond strength than Tokuyama Rebase $II^{(R)}$ but, there was no statistical significance(p<0.05). In the other groups, $Kooliner^{(R)}$ showed significantly higher shear bond strength(p<0.05). There was significant difference between groups with sandblasting and metal primer treatments(p<0.05). In comparison according to metal primer materials, Alloy $Primer^{(R)}$ showed the highest shear bond strength but there was no statistical significance(p>0.05). According to the number of thermocycling cycles, when using Tokuyama Rebase $II^{(R)}$, there were no significant differences between the 0, 1000 and 2000 cycle groups regardless of the type of metal primer. There were no differences between the 2000 and 3000 cycle groups. When using $Kooliner^{(R)}$, regardless of the type of metal primer, there were no significant differences between the 0, 1000, 2000 and 3000 cycle groups(p>0.05). Conclusion: The use of metal primers showed increase in bond strength, and the stability after to thermocycling has been authenticated. Thus, the use of metal primers in relining and rebasing of metal frameworks is essential. But when selecting the material various physical properties should be considered.

• 디지털융복합연구
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• 제12권12호
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• pp.441-447
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• 2014

본 연구는 대기업에 근무하는 산업체 근로자를 대상으로 비만도에 따른 척추안정화근력의 차이를 분석하는데 목적을 두었다. 편의표본 추출방법(Convenience Sampling Method)에 의하여 50명을 표본을 추출하여, 체질량지수(BMI) $25kg/m^2$ 이상을 비만군(25명), 이하를 정상군(25명)으로 분류하여 독립표본 t검정(Independent t-test)으로 분석하였다. 집단간 척추안정화근력의 측정결과 정상군의 평균이 비만군에 비해 모두 높았으며, Sagittal Plane에서는 $0^{\circ}$ Forward에서 유의한 차이를 보였고, Coronal plane에서는 $90^{\circ}$ Left, $90^{\circ}$ Right에서 유의한 차이를 보였으며, Diagonal Plane에서는 $45^{\circ}$ Left Tilt, $45^{\circ}$ Right Tilt에 유의한 차이를 보였다. BMI 분류에 따른 근육량과 골격근량의 분석결과에서는 비만군이 정상군에 비해 모두 높았으며 통계적으로 유의한 차이를 보였다. 비만군이 정상군에 비해 근육량은 많지만 척추안정화근력은 약하다는 것을 감안하여 Sagittal Plane, Coronal plane, Diagonal Plane에서의 비만인을 위한 척추안정화 강화 프로그램의 개발이 요구된다.

• Journal of the Korean Wood Science and Technology
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• 제43권3호
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• pp.287-294
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• 2015

본 연구는 4개 산지(유고슬라비아, 이탈리아, 영국, 불가리아)의 24년생 글루티노사오리나무를 대상으로 종압축 및 휨강도 특성을 규명하고, 또한 이들을 생장속도(평균연륜폭)와의 관계도 규명하였다. 압축강도는 $231{\sim}326kgf/cm^2$의 범위였고, 산지 간 차이를 보였다. 세 개 산지는 생장이 좋을수록 압축강도 및 압축영계수는 저하되는 것으로 나타났으나, Yugoslavia산지는 생장이 가장 좋으면서도 가장 높은 강도 값을 나타냈다. 휨강도는 $426{\sim}727kgf/cm^2$의 범위였고, 산지 간 차이가 있었다. 휨강도는 생장이 좋을수록 강도 및 영계수가 커지는 것으로 나타났다. 종자 산지가 다른 글루티노사오리나무 중 유고슬라비아산이 좋은 수고생장과, 다른 산지의 약 2배의 흉고직경을 나타내며, 압축, 휨강도에서도 가장 우수하여 생장과 재질면을 고려했을 때 현시점에서 가장 우수한 품종으로 판단된다.

• 한국자원식물학회지
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• 제16권3호
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• pp.223-229
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• 2003

본 연구는 양액재배 오이의 생장과 수량에 나쁜 영향을 주지 않는 적정 양액 농도를 구명하기 위해서 양액의 이온 농도를 달리하였다. Yamazaki의 오이 처방을 기본으로 하여 1/4, 1/2, 3/4, 1, 3/2, 2 배농도를 상이하게 처리하여 생장 특성, 수량 및 질소 함량을 비교하고자 수행하였고 그 결과를 요약하면 다음과 같다. 1. 생육 시기별 초장과 엽수의 증가속도는 저 농도 구인 1/2배 농도에서 가장 빠른 증가속도를 보였다. 2. 양액의 이온농도 차이에 따른 오이의 생육 형질은 유의적인 생장의 차이가 인정되지 않았으며, 생육 시기별 초장, 경장과 엽면적은 1/2배 농도구에서 수치상으로 가장 높은 값을 보였다. 3. 양액의 이온농도 차이에 따른 오이의 과실수량은 유의적인 차이가 인정되지 않았으며 주수에서는 고농도구인 2배 농도가 86.00, 86.75로 가장 높은 값을 보였고, 과실수는 1/4배 농도와 표준 농도에서 가장 낮은 74.25, 85.25를 보였으나 수량에서는 저 농도인 1/2배 농도와 3/4배 농도가 가장 높은 22.60, 22.07kg을 보였다. 4. 질소함량은 유의적인 차이가 인정되지 않았으며, l/2배 농도에서 대체적으로 높은 함량을 보였다. 5. 양액의 이온농도 차이에 따라 정식후 36일 조사 시기의 모든 생육형질과 수량 특성에서 수치상으로 높은 값을 보인 1/2배 농도에서의 상관관계는 초장과 경장은 고도로 유의한 정의 상관관계를, 초장과 엽면적에서는 유의한 정의 상관관계를 나타냈고, 주수와 과실수는 고도로 유의한 정의 상관관계를, 과실수와 수량은 유의한 정 의 상관을 나타냈다.

• 대한물리의학회지
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• 제8권3호
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• pp.467-477
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• 2013

PURPOSE: The purpose of this study was to identify the effects of backward pedaling ergometer training on ankle ROM, lower extremities strength, foot pressure in hemiplegia. METHODS: The subjects consisted of control group(n=10) and experimental group(n=10), subjects were trained 5 times a week for 2 weeks each group. Control group were trained forward, experimental group were trained backward pedaling with physical therapy in both groups. Each group measured ankle joint ROM with DUALER IQ and ankle and knee joint flexor and extensor muscle strength by Manual Muscle Test System and foot pressure by Gait view system. RESULTS: The result of this study between pre and post test that experimental group had statistically significantly differences in ankle joint range of motion and lower extremities strength. But foot pressure had not statistically significant differences. There was not significantly difference of variation between groups. CONCLUSION: Therefore these results mean that backward and forward pedaling ergometer training effected an improvement of lower extremities function in hemiplegia.

• Asian-Australasian Journal of Animal Sciences
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• 제29권10호
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• pp.1477-1482
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• 2016

This study was conducted to investigate the effects of diets with varying levels of calcium on egg production, shell quality and overall calcium status in aged laying hens. A total of five hundred 70-wk-old Hy-Line Brown layers were divided five groups and fed one of the five experimental diets with 3.5%, 3.8%, 4.1%, 4.4%, or 4.7% Ca, for 10 weeks. There were no significant differences in feed intake, egg production and egg weight among groups. The cracked eggs were linearly reduced as dietary Ca levels increased to 4.7% (p<0.01). A significant linear improvement for eggshell strength and thickness were determined with increasing dietary Ca levels (p<0.01). The contents of serum Ca and phosphorus were not affected by dietary Ca levels. With increase in dietary Ca levels, the tibial breaking strength slightly increased. There were no significant differences in the tibial contents of ash, Ca and phosphorus among groups. In conclusion, eggshell quality, as measured by appearance, strength and thickness of eggshell, were influenced by dietary Ca content as expected (p<0.05). These results suggested that aged laying hens require relatively higher level of Ca than required levels from current Korean feeding standards for poultry.

• 한국건축시공학회지
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• 제12권2호
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• pp.194-202
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• 2012

This paper predicts the cementing efficiency of fly-ash(FA) based on mortar test considering binder-water ratio and FA replacement ratio as experimental variables. The cementing efficiency prediction model proposed by statistical analysis enables us to estimate the value according to the binder-water ratio and FA replacement ratio of matrix. When FA replacement ratio is the same, the lower the binder-water ratio, the higher the estimated cementing efficiency. There are significant differences in the values according to binder-water ratio at FA replacement ratios of 15% or less, but there are almost no differences when FA replacement ratio is more than 15%. As the binder-water ratio increases, the variations in the values according to FA replacement ratio are great at FA replacement ratios of 15% or less. As the FA replacement ratios increase, the values increase for FA replacement ratios of 15% or less, but decrease for more than 15%. The values range from -0.71 to 1.24 at binder-water ratio of 1.67-2.86 and FA replacement ratio of 0-70%. The RMSE of the 28-day compressive strength predicted by modified water-cement ratio is 2.2 MPa. The values can be trusted, as there is good agreement between predicted strength and experimental strength.

• The Journal of Korean Physical Therapy
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• 제14권3호
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• pp.136-144
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• 2002

The Purpose of this study was to compare the lumbar strength and lumbar flexor/extensor ratio between spondylolisthesis and herniated disc patients. The patients who had a subacute low back pain have been proved to each disease through MRI and we measured the maximal isometric strength of all patients(28) through MedX lumbar extension machine(Ocala, FL). In all patients, males had higher lumbar extensor strength than that of females. Especially, the spondylolisthesis patients had lower lumbar extensor strength than that of herniated disc patients. The statistical significant(p<.05, p<.01) differences were manifested in $48^{\circ},\;60^{\circ}\;and\;72^{\circ}$ between male groups. Also the statistical significant (p<.05) differences were manifested in $60^{\circ}\;and\;72^{\circ}$between female groups. In the lumbar flexor/ extensor ratio, the males of spondylolisthesis groups represented the functional weakness in the flexed portion of the range of motion, and the females of spondylolisthesis and the all patients of herniated disc represented the functional weakness in the extended portion of the range of motion. In conclusion, we may propose the program such that the spondylolisthesis males must increase the ratio of extended portion exercise, and the spondylolisthesis females and herniated disc patients must increase the ratio of flexed portion exercise.

• The Journal of Korean Physical Therapy
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• 제34권3호
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• pp.110-115
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• 2022

Purpose: The purpose of this study was to examine the effect of sling exercise on pain, trunk strength, and balance in patients with chronic low back pain in their 40s and 50s. Methods: Twenty patients with chronic low back pain were divided into two groups, 10 patients in the exercise group using a sling and 10 patients in the waist stabilization exercise group, applying a random assignment, draw-out method, and sling exercise was applied for 50 minutes a day, 3 times a week, for a total of 5 weeks. For data analysis, a corresponding t-test was performed for within-group changes and an independent t-test was performed for inter-group changes, and the significance level was α=0.05. Results: After 5 weeks, there were significant differences in all items of within-group changes, and the inter-group changes after 5 weeks demonstrated significant differences in pain, trunk flexion strength, and balance. Conclusion: The results of this study showed that exercise using a sling had positive effects on pain, trunk flexion strength, and balance changes in chronic low back pain patients. It is suggested that sling exercise can be used as an intervention method for pain reduction and functional improvement of patients with chronic low back pain in clinical practice.

• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2000년도 가을 학술발표회 논문집
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• pp.569-576
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• 2000

This study performs a series of Triaxial Compression Test for clay-sand composite specimens changing area replacement ratio. Purpose of the test is to conform the propriety of weighted average method in estimating shear strength of the composite ground. The test results show that measured values of shear strength of composite specimens are larger by 20∼30% than those from estimation using the current weighted average method. It is thought that the differences are from pseudo-overconsolidation behavior of composite specimens.