• Composites Research
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• v.29 no.6
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• pp.342-346
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• 2016

Carbon fiber reinforced plastic (CFRP), one of lightweight materials, is the fiber structure using carbon fiber. It is the composite material that has the characteristics of carbon and plastic. As for the fiber structure, it has the great strength due to fiber direction. CFRP for woven type is used mostly as such a CFRP with lightweight. Woven type is more stable when compared with unidirectional type. On the other hand, woven type is highly priced. Therefore, this study aims to analyze the fiber structure of unidirectional CFRP. In this study, as the stacking angle [0/X/-X/0], X is the variable. This is unidirectional CFRP in which the angle phase of X has been reversed and stacked. By using such a unidirectional CFRP, the analysis model which had a crack at the center as the form of panel with the thickness of 2 mm was used. On analysis, the load is applied on the upper and lower parts being connected with a pin. The damage in the area near center crack was investigated. As for the analysis model, 3D surface model was designed by using CATIA. For CFRP stacking, the stacking direction was determined by using ACP in ANSYS program and the analysis model with two stacks was made. Afterwards, the structural analysis was carried out.

• Food Science and Preservation
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• v.13 no.2
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• pp.131-137
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• 2006

In order to reduce the damage of effective component during processing, we carried out hot-water extraction monitering in Gastrodia elata Blume by response surface methodology. The extraction con야tions for vanillyl alcohol, vanillin and coumarin were optimized at 91.07, 93.73 and $96.30^{\circ}C$, for 2.64, 2.58 and 3.84 hr, at the concentration of 15.16, 21.56 and 19.88 mL/g, respectively. The optimal condition for extraction of total phenolics was acheved at $98.14^{\circ}C$, 3.20 hr and 18.63 mL/g. This study elicited regression formula for each variable, and superimposed the total optimal conditions of extraction for effective compounds and optimal condition for antioxidant characteristics dividing processing factors. It is shown that the predicted result under the extraction condition as follows: extraction temperature for $90{\sim}100^{\circ}C$, extraction time for $3{\sim}4hr$, and solvent volume of $15{\sim}20mL/g$ of sample.

• Journal of the Korea Concrete Institute
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• v.29 no.2
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• pp.217-223
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• 2017

This research was planned to evaluate the structural performance of post tensioned(PT) concrete member subjected to fire. Prime objective was to suggest some techniques to evaluate the performance of post tensioned concrete beam and slab exposed to high temperature through experiment. To accomplish this objective, the following two scopes have been proceeded to verify the strength reducing ratio of strands and find out the difference of resisting force at the PT concrete members exposed to high temperature through the fire test. The properties of prestressing steel(tendon) in PT concrete beam and slab under variable temperatures were reviewed. The test of this study was shown that stress relaxation occurred at high temperature, and some restoration of tensional force appeared as it got cooling down. The residual tension of the post tensioned beams at 4 hours after reaching the target temperature were 70% at $400^{\circ}C$, 10% at $600^{\circ}C$ and 2% at $800^{\circ}C$. The post tensioned slabs were 94% at $400^{\circ}C$, 84.5% at $600^{\circ}C$ and 62% at $800^{\circ}C$. The reason why the residual tension loss of the post tensioned slab was relatively small was considered to be that the slab was exposed just one side to high temperature and the strength of the strand was restored larger than that of beam. Also, it was confirmed that the post tensioned member inevitably experienced the loss of strength by fire damage, and restoration design of the member should be required to compensate for the value as much as lost strength.

• Earthquakes and Structures
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• v.11 no.6
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• pp.1101-1121
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• 2016

Base isolation, one of the popular seismic protection approaches proven to be effective in practical applications, has been widely applied worldwide during the past few decades. As the techniques mature, it has been recognised that, the biggest issue faced in base isolation technique is the challenge of great base displacement demand, which leads to the potential of overturning of the structure, instability and permanent damage of the isolators. Meanwhile, drain, ventilation and regular maintenance at the base isolation level are quite difficult and rather time- and fund- consuming, especially in the highly populated areas. To address these challenges, a number of efforts have been dedicated to propose new isolation systems, including segmental building, additional storey isolation (ASI) and mid-storey isolation system, etc. However, such techniques have their own flaws, among which whipping effect is the most obvious one. Moreover, due to their inherent passive nature, all these techniques, including traditional base isolation system, show incapability to cope with the unpredictable and diverse nature of earthquakes. The solution for the aforementioned challenge is to develop an innovative vibration isolation system to realise variable structural stiffness to maximise the adaptability and controllability of the system. Recently, advances on the development of an adaptive magneto-rheological elastomer (MRE) vibration isolator has enlightened the development of adaptive base isolation systems due to its ability to alter stiffness by changing applied electrical current. In this study, an innovative semi-active storey isolation system inserting such novel MRE isolators between each floor is proposed. The stiffness of each level in the proposed isolation system can thus be changed according to characteristics of the MRE isolators. Non-dominated sorting genetic algorithm type II (NSGA-II) with dynamic crowding distance (DCD) is utilised for the optimisation of the parameters at isolation level in the system. Extensive comparative simulation studies have been conducted using 5-storey benchmark model to evaluate the performance of the proposed isolation system under different earthquake excitations. Simulation results compare the seismic responses of bare building, building with passive controlled MRE base isolation system, building with passive-controlled MRE storey isolation system and building with optimised storey isolation system.

• Asian Pacific Journal of Cancer Prevention
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• v.17 no.sup3
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• pp.81-85
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• 2016

Globally, the burden of breast cancer (BC) continues to increase. BC related lymphedema (BCRL) is currently non curable and as a life time risk it affects at least 25% of BC patients. Knowing more about BCRL and appropriate control of its modifiable risk factors can improve quality of life (QOL) of the affected patients. In this case control study to detect factors, 400 women with BCRL (as the case group) and 283 patients with BC without lymphedema (as the control group) that were referred to Shiraz University of Medical Sciences affiliated BC clinic center were assessed. The data were analyzed in SPSS. The mean age of the case group was $52.3{\pm}11.0years$ and of the control group was $50.1{\pm}10.9years$. In patients with BCRL, 203(50.7%) had left (Lt) side BC and in non- lymphedema group 151 (53.3%) had Lt side BC. Out of all BCRL patients, 204 (51%) had lymphedema in all parts of their affected upper extremities, 100 (25%) had swelling in the arm and forearm and 23 (5.7%) had edema in both the upper extremity and trunk. Edema, heaviness, concern about changing body image, pain and paresthesia were the most common signs/symptoms among patients with BCRL. In BCRL patients, the difference of circumference between the affected upper limb and non-affected limb was $4.4{\pm}2.5cm$ and the difference in volume displacement was $528.7{\pm}374.4milliliters$. Multiple variable analysis showed that moderate to severe activity (OR; odds ratio =14, 95% CI :2.6-73.3), invasiveness of BC (OR =13.7, 95% CI :7.3-25.6), modified radical mastectomy (OR=4.3, 95% CI :2.3-7.9), BMI =>25 (OR=4.2, 95% CI :2-8.7), radiotherapy (OR=3.9, 95% CI :1.8-8.2), past history of limb damage (OR=1.7, 95% CI :0.9-3.1) and the number of excised lymph nodes (OR=1.06, 95% CI :1.02-1.09) were the significant predictors of lymphedema in women with BC. Modifiable risk factors of BCRL such as non-guided moderate to severe physical activity, high BMI and trauma to the limb should be controlled as early as possible in BC patients to prevent development of BCRL and improve QOL of these patients.

• The Journal of the Korea Contents Association
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• v.13 no.2
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• pp.370-377
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• 2013

Traumatic brain injury(TBI) is a brain damage caused by an external physical force. TBI patients have disturbances of functioning including attention, memory, reasoning,, executive function, and pragmatic language. The aim of this study was to develop the cognitive-pragmatic language ability assessment protocol for traumatic brain injury(CAPTBI) and to evaluate reliability and validity. This study was also conducted to investigate domains that contributed to differentiate between the normal and TBI groups. The CAPTBI data were obtained from 226 normal adults and 62 TBI patients(mean age=$43.95{\pm}11.92$, $46.37{\pm}11.87$, M:F=110:116, 48:14). The CAPTBI had high item internal consistency, test-retest reliability, construct validity, and concurrent validity. The normal group performed significantly better than the TBI group in all domains of the CAPTBI and the separate scores for 9 domains. All 9 domains were found to be significant variables to discriminate between the two groups. The most powerful variable was executive function followed by memory, organization, pragmatic language, problem-solving, attention, orientation, reasoning, and visuoperception in order. The CAPTBI could discriminate between the two groups accurately by 95.5%. This result demonstrated that 97.3% of normal adults and 88.7% of TBI patients could be discriminated by CAPTBI. In conclusion, The CAPTBI is appropriate for evaluating and identifying cognitive-pragmatic language disorders in TBI patients.

• Journal of the Korean Association of Oral and Maxillofacial Surgeons
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• v.33 no.3
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• pp.191-198
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• 2007

The p53 which is well known as tumor suppressor gene is located at 17p13. p53 is a sequence-specific DNA binding transcription factor that responds to certain cytotoxic stresses, such as DNA damage, by enhancing the transcription of genes that regulate cell-cycle progression as well as programmed cell death. The p63 gene that is located at 3q27-29, is recognized members of the p53 family, and responsible for the transcription of 6 isoforms. Three isoforms ($TAp63{\alpha}$, $TAp63{\beta}$, $TAp63{\gamma}$) contain an N-terminal transactivation (TA) domain and can induce apoptosis. The other 3 isoforms (${\Delta}Np63{\alpha}$, ${\Delta}Np63{\beta}$, ${\Delta}Np63{\gamma}$) lack the TA domain and may function in a dominant-negative fashion by inhibiting the transactivation functions of p53 and TAp63 proteins, and thus act as oncoproteins. A number of studies have investigated the role of p63 in human squamous cell carcinomas from different organs. Only a few studies have examined ${\Delta}Np63$ isoform in oral squamous cell carcinoma including normal epithelium. This study aimed to evaluate expression of ${\Delta}Np63$ isoform in human oral squamous cell carcinoma tissue and normal mucosa. The 3 cases of well differenciated oral squamous cell carcinoma specimen including adjacent normal mucosa were examined, and immunohistochemical study with monoclonal antibody(4A4) and tumor cell apoptosis analysis with Transmission Electon Microscopy were studied. And, RT-PCR analysis was done for expression of ${\Delta}Np63$ isoform. The results were as followed. 1. Normal gingiva showed the restricted p63 expression in basal cell layer. 2. Well differentiated squamous cell carcinoma showed mainly p63 expression in overall area of malignancy, especially in basal cell layer to adjacent stromal tissue. 3. Tumor cells around keratinized area with no p63 expression disclosed less micro-organelle in decreased size cytoplasm and severe chromatin margination with nuclear destruction that means apoptosis. 4. Comparison of mRNA expression of ${\Delta}Np63$ isoform by RT-PCR showed variable expression of ${\Delta}Np63$ isoform, but ${\Delta}Np63{\alpha}$ was most highly expressed in all 3 tumor specimen. From theses results, it should be suggested that ${\Delta}Np63$ isoform expression in well differentiated squamous cell carcinoma was closely related to tumor oncogenesis, expecially overexpression of ${\Delta}Np63{\alpha}$ is a most important factor in tumor genesis of oral squamous cell carcinoma.

• Journal of Astronomy and Space Sciences
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• v.21 no.2
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• pp.141-152
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• 2004

Optics fabrication process for precision space optical parts includes bound abrasive grinding, loose abrasive lapping and polishing. The traditional bound abrasive grinding with bronze bond cupped diamond wheel leaves the machine marks of about $20{mu}m$ rms in height and the subsurface damage of about 1 ${mu}m$ rms in height to be removed by subsequent loose abrasive lapping. We explored an efficient quantitative control of precision CNC grinding. The machining parameters such as grain size, work-piece rotation speed and feed rate were altered while grinding the work-piece surfaces of 20-100 mm in diameter. The input grinding variables and the resulting surface quality data were used to build grinding prediction models using empirical and multi-variable regression analysis. The effectiveness of such grinding prediction models was then examined by running a series of precision CNC grinding operation with a set of controlled input variables and predicted output surface quality indicators. The experiment achieved the predictability down to ${pm}20$ nm in height and the surface roughness down to 36 nm in height. This study contributed to improvement of the process efficiency reaching directly the polishing and figuring process without the need for the loose abrasive lapping stage.

• Journal of Korea Water Resources Association
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• v.40 no.3
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• pp.223-236
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• 2007

Recently in urban area flood damages increase due to local concentrated heavy rainfall. Even in the cities where stormwater drainage systems are relatively well established flood damage still occurs because of the capacity limitations of the existing stormwater drainage systems. When the flood exceeds the capacity limitation of the urban storm sewer system, it yields huge property losses of public facilities involving roadway inundation to paralyze industrial and transportation system of the city. To prevent such flood damages in urban area, it is necessary to develop adequate inundation analysis model which can consider complicated geometry of urban area and artificial drainage system simultaneously. The Dual-Drainage model used in this study is the urban inundation analysis model which combines SWMM with DEM based 2-dimensional surface flood inundation model. In this study, the dual drainage model has been modified to consider the effect of complex buildings in urban area. Through the simulation of time variable inundation process, it is possible to identify inundation alert locations as well as to establish emergency action plan for the residencial area vulnerable to flood inundation.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.21 no.3
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• pp.241-253
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• 2009

This study performs the investigation of a long-term variation of annual maximum surge heights(AMSH) and main characteristics of high surge events, and the statistical evaluation of the AMSH using sea level data at Yeosu and Tongyeong tidal stations over more than 30 years. It is found that the long-term uptrends based on the linear regression in the AMSH are 34.5 cm/34 yr at Yeosu and 33.6 cm/31 yr at Tongyeong, which are relatively much higher than those at Sokcho and Mukho in the Eastern Coast. 71% and 68% of the AMSH occur during typhoon's event in Yeosu and Tongyeong tidal stations, respectively, and the highest surge records are mostly produced by the typhoon. The generalized extreme value distribution taking into account of the time variable is applied to detect time trend in annual maximum surge heights. In addition, Gumbel distribution is checked to find which one is best fitted to the data using likelihood ratio test. The return level and its 90% confidence interval are obtained for the statistical prediction of the future trend. The prevention of the growing storm surge damage by the intensified typhoon requires the steady analysis and prediction of the surge events associated with the climate change.