• Structural Engineering and Mechanics
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• v.66 no.5
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• pp.569-582
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• 2018

Effects of crack separation, bridge area, on the tensile behaviour of concrete are studied experimentally and numerically through the Brazilian tensile test. The physical data obtained from the Brazilian tests are used to calibrate the two-dimensional particle flow code based on discrete element method (DEM). Then some specially designed Brazilian disc specimens containing two parallel cracks are used to perform the physical tests in the laboratory and numerically simulated to make the suitable numerical models to be tested. The experimental and numerical results of the Brazilian disc specimens are compared to conclude the validity and applicability of these models used in this research. Validation of the simulated models can be easily checked with the results of Brazilian tests performed on non-persistent cracked physical models. The Brazilian discs used in this work have a diameter of 54 mm and contain two parallel centred cracks ($90^{\circ}$ to the horizontal) loaded indirectly under the compressive line loading. The lengths of cracks are considered as; 10 mm, 20 mm, 30 mm and 40 mm, respectively. The visually observed failure process gained through numerical Brazilian tests are found to be very similar to those obtained through the experimental tests. The fracture patterns demonstrated by DEM simulations are mostly affected by the crack separation but the tensile strength of bridge area is related to the fracture pattern and failure mechanism of the testing samples. It has also been shown that when the crack lengths are less than 30 mm, the tensile cracks may initiate from the cracks tips and propagate parallel to loading direction till coalesce with the other cracks tips while when the cracks lengths are more than 30 mm, these tensile cracks may propagate through the intact concrete itself rather than that of the bridge area.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.5 no.1
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• pp.39-51
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• 1999

Background and Purpose. Objective measurements of hamstring muscle length are needed to quantify baseline limitations and to document the effectiveness of therapeutic interventions. Several indirect clinical tests for measuring hamstring muscle length are available, but influence of their test procedure is not well documented. The purpose of this study were 1) to describe hamstring muscle length as reflected by use of six tests(active straight leg raising(ASLR), passive straight leg raising(PSLR), passive straight leg raising with the lower back flat(PSLRB), active knee extension(AKE), passive knee extension(PKE), hip joint angle(HJA). 2) to examine the correlation among the tests. Subjects, Sixty subjects(30 men. 30 women) ranging in age from 18 to 25 years(mean 20.2 years) and with no limitation hamstring flexibility and no neurological and orthopedical problems. Methods. All subjects performed six tests. A inclinometer was used to determine the end point of range of motion. HJA was measured using an inclinometer placed over the sacrum. PSLRB were tested PSLR with the low back flat and the opposite thigh slightly flexed and support on pillows. Results, A mean ASLR value of 85.9 degrees, PSLR value of 99.9 degrees, PSLRB value of 109.8 degrees, AKE value of 77.2 degrees PKE value of 83.1 degrees and HJA value of 73.0 degrees were obtained for all subjects. A dependent t-test showed significant difference between the angles of ASLR and PSLR(p<0.001). There was a significant difference between the angles of PSLR and PSLRB(p<0.001). There was a significant difference between the angles of AKE and PKE(p<0.001). The highest correlation was between PSLR and PSLRB(r=0.915, p<0.001). All SLR tests were significants related(p<0.001), as well as AKE and PKE(p<0.001). The lowest correlation was between PKE and HJA(r=0.171. p>0.05). Conclusion and Discussion. The results indicated that the hip flexion angles for ASLR, PSLR and PSLRB were a difference, and the knee extension angles for AKE and PKE were a difference.

• Proceedings of the Korea Society of Mathematical Education Conference
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• 2010.04a
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• pp.307-309
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• 2010

• Physical Therapy Korea
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• v.13 no.2
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• pp.26-34
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• 2006

The aim of this study was to assess the effectiveness of group therapeutic exercise programs on the cognitive function, Activities of Daily Living (ADL), and balance-performing ability in older adults. Fifteen community-dwelling subjects (mean age 73.7 yrs, standard deviation 2.4) participated in this study. An 8-week group therapeutic exercise program, including strengthening and balance training, breathing and gait exercise, and recreation, consisted of activities related to daily living. The Mini-Mental State Examination-Korean (MMSE-K), Modified Barthel Index (MBI), Berg Balance Scale (BBS), Functional Reaching Test (FRT), and Timed Up & Go (TUG) test were measured during pre-exercise and post-exercise points. The results of this study were as follows: 1. After eight weeks, the MMSE-K and MBI total score was more significantly increased for post-exercise tests than pre-exercise tests (respectively, p<.05, p<.01). 2. Of the MBI contents, personal hygiene, dressing, ambulation, and chair/bed transfers scores were significant increased for post-exercise tests. 3. Post exercise BBS, FRT, and TUG scores were higher than the pre-exercise scores. The difference was statistically significant (respectively, p<.05, p<.05, p<.01). These findings suggest that group therapeutic exercise can be used to improve the cognitive function, ADL, and balance-performing ability in elderly persons.

• Bulletin of the Korean Chemical Society
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• v.29 no.5
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• pp.1038-1042
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• 2008

Mono and multilayer TiO2(Fe, $PEG_{600}$) films were deposited by the dip-coating on $SiO_2$/glass substrate using sol-gel method. In an attempt to improve the antibacterial properties of doped $TiO_2$ films, the influence of the iron oxides and polyethilenglycol ($PEG_{600}$) on the morphological, optical, surface chemical composition and biological properties of nanostructured layers was studied. Complementary measurements were performed including Spectroscopic Ellipsometry (SE), Scanning Electron Microscopy (SEM) coupled with the fractal analysis, X-Ray Photoelectron Spectroscopy (XPS) and antibacterial tests. It was found that different concentrations of Fe and $PEG_{600}$ added to coating solution strongly influence the porosity and morphology at nanometric scale related to fractal behaviour and the elemental and chemical states of the surfaces as well. The thermal treatment under oxidative atmosphere leads to films densification and oxides phase stabilization. The antibacterial activity of coatings against Escherichia Coli bacteria was examined by specific antibacterial tests.

• Journal of Yeungnam Medical Science
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• v.41 no.3
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• pp.220-227
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• 2024

Background: Electrodiagnostic testing (EDX) is important in the diagnosis and follow-up of neuropathic and myopathic diseases. This study aimed to demonstrate the compatibility between clinical prediagnosis and electrophysiological findings. Methods: EDX results from 2004 to 2020 at the physical medicine and rehabilitation (PM&R) clinic were screened. Tests with missing data, reevaluation studies, and cases of peripheral facial paralysis were excluded. The clinical prediagnosis and EDX results were recorded, and their compatibility was evaluated. Results: A total of 2,153 tests were included in this study. The mean age was 49.0±13.9 years and 1,533 of them (71.2%) were female. The most frequently referred clinic was the PM&R clinic (90.0%). Numbness (73.6%) was the most common complaint, followed by pain (15.3%) and weakness (13.9%). The most common prediagnosis was entrapment neuropathy (55.3%), radiculopathy (16.1%), and polyneuropathy (15.7%). Carpal tunnel syndrome was the most frequently identified type of entrapment neuropathy (78.3%). Six hundred and seventy EDX results (31.1%) were within normal limits. While the EDX results were consistent with the prediagnosis in 1,328 patients (61.7%), a pathology different from the prediagnosis was detected in 155 patients (7.2%). In the discrepancy group, the most common pathologies were entrapment neuropathy (51.7%), polyneuropathy (17.3%), and radiculopathy (15.1%). The most common neuropathy type was carpal tunnel syndrome (79.3%). Conclusion: After adequate anamnesis and physical and neurological examinations, requesting further appropriate tests will increase the prediagnosis accuracy and prevent unnecessary expenditure of time and labor.

• The Journal of Korean Physical Therapy
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• v.17 no.4
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• pp.621-631
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• 2005

The purpose of this study was to measure magnitude of lower leg muscle activity during dynamic stability tests performed on an unstable board by subjects with sprained lateral ankles. Fifteen lateral ankle sprain subjects(8 male, 7 female) participated in this study. The muscle activity was measured at gastrocnemious, tibialis anterior, peroneus longus during dynamic stability tests performed on Biodex stability system as surface EMG. The EMG amplitude of each muscle was normalized to the amplitude in the maximal voluntary isometric contraction(MVIC) of each muscle. As results, peroneus longus evidenced significant difference at stable and unstable grade comparing injured with uninjured sides. Gastrocnemious and tibialis anterior evidenced no significant difference. Change of muscle activity with stable and unstable grade evidenced no significant difference on injured and uninjured sides. The data provided information on peroneus longus contributes to dynamic stability after lateral ankle sprains. Peroneus longus training program may have to be emphasized after an ankle sprain.

• Journal of Korean Physical Therapy Science
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• v.6 no.3
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• pp.63-82
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• 1999

Recent studies have revealed that Nitric oxide(NO) was one of the demonstration for the physiological regulator, endothelial derived relaxing factor(EDRF) and that NO was produced by ultraviolet irradiation in human. Thus, the present author have carried out a experimental study on the change of hematological, histological value of ultraviolet irradiation in sprague-dawley rats. The subjects were divided into four groups of ten rats each selected at random. There were 4 groups: 1. no irradiation control; 2. ultraviolet $75mJ/cm^2$ irradiation group; 3. ultraviolet $150mJ/cm^2$ irradiation group; 4. ultraviolet $225mJ/cm^2$ group. After a irradiation, hematological and histological tests were performed to observe erythrocyte, hemoglobin, hematocrit, MCH, MCHC, MCV, $O_2$ saturation, pH, $PO_2,\;PCO_2$ value and to observe histological changes. In hematological tests, erythrocyte, hemoglobin, hematocrit significantly increased in $75mJ/cm^2$ than control group and more $150mJ/cm^2$ ultraviolet irradiation group respectively. Also In blood gas tests, $PO_2$ significantly increased in $75mJ/cm^2$ and more $150mJ/cm^2$ group than control group. Whereas $PCO_2$ significantly decreased in $75mJ/cm^2$ and more $150mJ/cm^2$ group than control group (Duncan-Tukey test, P<0.05). In histological tests, control and $75mJ/cm^2$ group unchanged, but more $150mJ/cm^2$ group changed that it was cytolysis, cytotoxic effect, acanthosis, proliferation of keratinocyte, appearance of amorphous cell and pyknotic nucleus, production of sunburn cell. In conclusion, the present author results support the importance of the relation between NO effect and hematological, histological value by ultraviolet B irradiation.

• Journal of the Korean Society of Physical Medicine
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• v.7 no.3
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• pp.259-265
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• 2012

Purpose : Patients with Parkionson's disease have a temporal and spatial restriction for their's exercise treatment. The aim of this study is to verify the effectiveness of e-exercise program on balance, gait, and endurance ability in people with Parkinson's disease. Methods : Eighteen participants, with Parkinson's disease that ranged from stage to on the Hoehn & Yahr scale, were assigned to two group. Two group were divided into on-line group that exercised in home by computer video, and off-line group that exercised in clinical center. Exercise program that included 3 sections (warm-up, main exercise, cool down)-5 parts(stretch, strength, balance, gait, stretch) was used to train for participants. We used the functional reach test for balance ability, timed up and go test for gait ability, 6 minute walking test for endurance ability. Wilkoxon sign lank tests were used to assess the difference of balance, gait, and endurance ability in pre-and post test each groups. Mann-whitney tests were used to assess the difference of balance, gait, and endurance ability between groups. Results : Wilkoxon sign lank tests revealed that both group were improved the balance, gait and endurance agility by e-exercise program intervention. Mann-whitney tests showed that there were no differences between groups in the variation of balance, gait, endurance ability. Conclusion : We believe that exercise program with on-line(e-exercise program) is an effective intervention for people with Parkinson's disease and is no different than off-line exercise group in the variation of balance, gait, endurance ability.

• The Journal of Korean Physical Therapy
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• v.34 no.5
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• pp.193-197
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• 2022

Purpose: The purpose of this pilot study was to assess the feasibility of a proposed study "To investigate the effects of applying a vibration stimulation to the paretic and non-paretic sides on balance and gait in stroke patients" before proceeding with the main study. Methods: A total of 30 patients who had suffered a stroke and who met the selection criteria participated in this study. However, only 14 patients completed the study. The study subjects were randomly assigned to vibration stimulation on either both sides (B group) or the paralyzed side (P group). The interventions were applied for six weeks. The patients were assessed using the Berg balance scale (BBS), Timed up and go (TUG), 10-meter walk (10 MW), and 6-minute walk (6 MW) tests. Results: There was a significant difference before and after the application of vibration stimulation in the BBS, TUG, 10MW, and 6 MW tests in the B group (p<0.05). Similarly, there was also a significant difference observed in the 10 MW and 6 MW tests in the P group (p<0.05). The difference between the two groups was not significant in the BBS, TUG, 10 MW, and 6 MW tests (p>0.05). Conclusion: This pilot study suggests that it would be feasible to conduct a large-scale randomized controlled trial (RCT) to examine the effects of applying a vibration stimulation to the paretic and non-paretic sides, on the balance and gait in stroke patients.