• 한국지반공학회:학술대회논문집
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• 한국지반공학회 2008년도 춘계 학술발표회 초청강연 및 논문집
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• pp.894-904
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• 2008

In this study, soil samples from the Antarctic and Vladivostok, Siberia were tested in the laboratory, and specific gravity, compaction curve and grain size distribution were determined. The effect of temperature change on the thermal conductivity, unfrozen water content and compressive strength were investigated. Samples for the compressive strength test were prepared in a mold with a fixed volume to prevent swelling and the effect of temperature and water content change on the strength were compared. Results from the thermal conductivity test showed that thermal conductivity values for both soils were larger at temperatures below freezing than above freezing. The unfrozen water content dropped sharply within a temperature range of $0{\sim}-5^{\circ}C$ and then gradually decreased further up to $-20^{\circ}C$. Compressive strength test results showed various stress/deformation curves with a change in water content. Sandy soil had much larger strength than pure ice at an identical temperature, while clayey soil had a smaller strength than ice near the freezing point, but showed a larger strength at temperatures belows $-15^{\circ}C$.

• Computers and Concrete
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• 제8권5호
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• pp.491-510
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• 2011

Before deciding if structures exposed to high temperature are to be repaired or demolished, their final state should be carefully examined. Destructive and non-destructive testing methods are generally applied for this purpose. Compressive strength and color change in mortars are observed as a result of the effects of high temperature. In this study, ordinary and pozzolan-added mortar samples were produced using different aggregates, and exposed to 100, 200, 300, 600, 900 and $1200^{\circ}C$. The samples were divided into two groups and cooled to room temperature in water and air separately. Compression tests were carried out on these samples, and the color change was evaluated by the Munsell Color System. The relationships between the change in compressive strength and color of mortars were determined by using a multi-layered feed-forward Neural Network model trained with the back-propagation algorithm. The results showed that providing accurate estimates of compressive strength by using the color components and ultrasonic pulse velocity design parameters were possible using the approach adopted in this study.

• The Journal of Korean Physical Therapy
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• 제13권3호
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• pp.579-584
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• 2001

The purpose of this study was to determine the effects of kinesio taping on lumbar muscle strength and flexibility. The samples for this study were 61 normal subjects(35 experimental group, 26 control group), aged 19 to 29 years. The data were analyzed by paired t-test. pearson and bivariate correlations. The results of this study were as follows : 1. The lumbar muscle strength was significant change in the experimental group(p<0.05). 2. The lumbar muscle strength was no significant change in the control group(p>0.05). 3. The flexibility was significant change in the experimental group and control group(p<0.05). 4. The lumbar muscle strength and flexibility were high associated in between session reliability(p<0.05).

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2003년도 춘계학술발표회
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• pp.167-172
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• 2003

Place that have cutout inner bottom and girder and floor etc. in hull construction absence is used much, and this is strength in case must be situated, but establish in region that high stress interacts sometimes fatally in region that there is no big problem usually by purpose of weight reduction, a person and change of freight piping etc.. Because cutout's existence gnaws in this place, and, elastic buckling strength by load causes large effect in ultimate strength. Therefore, perforated plate elastic buckling strength and ultimate strength is one of important design criteria which must examine when decide structural elements size at early structure design step of ship. Therefore, and, reasonable elastic buckling strength about perforated plate need design ultimate strength. Calculated ultimate strength change several aspect ratioes and cutout's dimension. and thickness in this investigation. Used program applied ANSYS F.E.M code transformation finite element law that is mediocrity finite element analysis code.

• 한국전산구조공학회:학술대회논문집
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• 한국전산구조공학회 2004년도 가을 학술발표회 논문집
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• pp.237-244
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• 2004

Plate that have cutout inner bottom and girder and floor etc. in hull construction absence is used much, and this is strength in case must be situated, but establish in region that high stress interacts sometimes fatally in region that there is no big problem usually by purpose of weight reduction, a person and change of freight, piping etc.. Because cutout's existence gnaws in this place, and, elastic buckling strength by load causes large effect in ultimate strength. Therefore, perforated plate elastic buckling strength and ultimate strength is one of important design criteria which must examine when decide structural elements size at early structure design step of ship. Therefore, and, reasonable elastic buckling strength about perforated plate need design ultimate strength. Calculated ultimate strength change several aspect ratioes and cutout's dimension, and thickness in this investigation. Used program applied ANSYS F.E.M code based on finite element method.

• 기술표준
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• 통권12호
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• pp.67-78
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• 2003

In order to keep a characteristic corrugated fibreboard of fruits and flowers, temperature and humidity change of corrugated fibreboard are analyzed. According to relative humidity rises at fixed temperature, bursting strength of corrugated fibreboard was fallen and double wall corrugated fibreboard appeared greatly the bursting strength decline rate than double faced corrugated fibreboard and edgewise compressive strength of paper more than humidity 80% in rapidly fall. A column crush test of paper became decrease in the high temperature and ordinary temperature strength did over humidity 70% rapidly fallen and strength decrease happened by low temperature 80% slowly fallen and later rapidly. According to ISO standard temperature humidity conditioning (23$\pm$2 , 50$\pm$2%) change, pulp composition difference as to the ring crush strength of a physical strength and generally compare to KS standard increased 5∼8% for the compressive strength, and wet strength reagent was increased 4% inside and out.

• 대한치과보철학회지
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• 제41권1호
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• pp.71-80
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• 2003

Development of new ceramic and esthetic need of patient increased the use of ceramic restorations. The purpose of this study was to confirm the possibility of recycling for IPS Empress2 which has a lot of advantages in esthetics. 1st, 2nd and 3rd pressed disc-shaped($10{\times}1.5mm$) IPS Empress 2 specimens were made with IPS Empress ingot(shade 200, Ivoclar, Liechtenstein) and pressing furnace(IPS Empress EP 500, Ivoclar, Liechtenstein). Flexure strength was measured with universal testing machine(Zwick 145641, Zwick, Germany), and color change and staining resistance of specimens were evaluated with colorimeter (Model TC-6FX, Tokyo Denshoku Co., Japan). The followings were drawn from this study : 1. Flexure strength of the 1st, the 2nd, and the 3rd pressed specimens showed 236.78 MPa. 247.16MPa, and 220.72MPa, respectively. Flexure strength of the 2nd pressed specimens was higher than others, but there's no statistical difference between them. 2. The color difference between the 1st and the 2nd pressed specimens was 3.25, and that between the 1st and the 3rd pressed specimens was 3.63(P<0.05). 3. The color change after staining of the 1st, the 2nd. and the 3rd pressed specimens were 1.43, 2.64, and 1.45, respectively. In this study, reused IPS Empress 2 specimens showed insignificant change of flexure strength and stain resistance, but they showed some color change according to reuse. From this results, the limited possibility of reuse for IPS Empress 2 could be considered.

• 한국농공학회:학술대회논문집
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• 한국농공학회 1999년도 Proceedings of the 1999 Annual Conference The Korean Society of Agricutural Engineers
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• pp.283-288
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• 1999

This study is performed to evaluate slump , air content, compressive strength and length change ratio of non-shrinkage high strength ocncrete is achieved by 10% expansive additive contained. The length change ration of non-shrinkage high strength concrete which is in water curing, shows 0.055% expansion in 10% expansive additive contained concrete and 0.308 expansion in 20% expansion additive contained concrete when it is curing 28 days.

• 한국운동역학회지
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• 제16권4호
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• pp.195-203
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• 2006

The isometric rehabilitation program was applied to 47 people of the aged low back patients(man 22 people, woman 25 people) twice a week for 8weeks. The Medx was used to study an effect on a change for extended strength ratio(ESR) according to a posture change. The isometric ESR at each flexion angle ($0^{\circ}$, $12^{\circ}$, $24^{\circ}$, $36^{\circ}$, $48^{\circ}$, $60^{\circ}$, $72^{\circ})$ was measured total 3times("before excercise", "on 4th week after excercise", "8th week after excercise") and analyzed. So, we could come to a conclusion as follows. 1. The maximum extended strength measured at a range of 7 angles for an isometric excercise of 8 weeks increased than "before an excercise", including that men have an increase of 39.51% and women have 62.92% in training effect. All of men and women showed statistically significant increase in physical strength(p<.001).excercise") and analyzed. So, we could come to a conclusion as follows. 2. After an excercise of 8 weeks, man showed 62.17% at zero degree and 49.115% at 12 degree respectively in maximum extended strength. Women showed 106.6% at zero degree and 86.16% at 12 degree. In view of this, respectively man have increase rate of physical strength over 31% and women have over 46% at all angles, also have significant increase in extension angle(p<.001). 3. A change for isometric ESR have a decrease of 27.68% for men and 74.66% for women than before isometric excercise of 8 weeks statistically significantly(p<.05, p<.00l). Men showed 1.77:1 of a similar ratio in the decrease effect comparing with normal people, but women showed 225:1.

• 대한통합의학회지
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• 제11권1호
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• pp.121-130
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• 2023

Purpose : This study aimed to investigate the effect of blood flow restriction exercise on ankle muscle strength and balance ability to achieve maximum efficiency with the same exercise intensity and time. Methods : Twenty-six adults are randomly assigned to experimental group (n=13) and comparison group (n=13). The experimental group performed ankle joint strength exercises with blood flow restriction applied while the comparison group performed ankle joint strength exercises without blood flow restriction applied three times a week for four weeks. The digital muscle measurement, Y-balance test, and Cumberland ankle instability tool were used to evaluate the subject's muscle strength, dynamic balance, and ankle instability index before and after the intervention. Results : In within-group comparison muscle strength, all the two groups showed significant improvements post intervention (p<.05). In between-group comparison, there was significant difference in the change of dorsiflexion, eversion strength pre and post intervention (p<.05). but plantarflexion was no significant difference between pre and post intervention in the group comparison (p>.05). In within-group comparison dynamic balance, all the two groups showed significant improvements post intervention (p<.05). In between-group comparison, there was no significant difference in the change of Y-balance score pre and post intervention (p>.05). In within-group comparison ankle instability index, all the two groups showed significant improvements post intervention (p<.05). In between-group comparison, there was no significant difference in the change of CAIT score pre and post intervention (p>.05). Conclusion : The results of this study show that ankle joint strength exercise improved the strength and balance ability of those complaining of chronic ankle instability, and ankle joint strength exercise applied with blood flow restriction was more effective in dorsiflexion and eversion strength exercise than ankle joint strength exercise without blood flow restriction.