• Fire Science and Engineering
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• v.30 no.6
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• pp.78-83
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• 2016

The characteristics of flame spread under similar atmospheric conditions to those inside the first stage of launch vehicles were investigated to provide fundamental knowledge to prevent fires and explosions of vehicles during launching operations. To this end, the rate of flame spread on the solid fuel was measured at elevated oxygen concentrations and reduced atmospheric pressures. A 0.18 mm diameter optical fiber was used as a solid fuel. The experimental results indicated that elevated oxygen concentrations can increase the rate of flame spread while increasing the atmospheric pressures to 1 atm can lead to decreases in the rate of flame spread. The increases in the rate of flame spread with pressure is due mainly to reductions in the convective heat loss that are clarified through an analysis of the pressure dependence on the convective heat transfer coefficient.

• Steel and Composite Structures
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• v.16 no.5
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• pp.491-506
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• 2014

Buckling-restrained braces (BRBs) have excellent hysteretic behavior while buckling-restrained braced frames (BRBFs) are susceptible to residual lateral deformations. To address this drawback, a novel self-centering (SC) BRB with Basalt fiber reinforced polymer (BFRP) composite tendons is presented in this work. The configuration and mechanics of proposed BFRP-SC-BRBs are first discussed. Then an 1840-mm-long BFRP-SC-BRB specimen is fabricated and tested to verify its hysteric and self-centering performance. The tested specimen has an expected flag-shaped hysteresis character, showing a distinct self-centering tendency. During the test, the residual deformation of the specimen is only about 0.6 mm. The gap between anchorage plates and welding ends of bracing tubes performs as expected with the maximum opening value 6 mm when brace is in compression. The OpenSEES software is employed to conduct numerical analysis. Experiment results are used to validate the modeling methodology. Then the proposed numerical model is used to evaluate the influence of initial prestress, tendon diameter and core plate thickness on the performance of BFRP-SC-BRBs. Results show that both the increase of initial prestress and tendon diameters can obviously improve the self-centering effect of BFRP-SC-BRBs. With the increase of core plate thickness, the energy dissipation is improved while the residual deformation is generated when the core plate strength exceeds initial prestress force.

• Advances in environmental research
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• v.6 no.2
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• pp.127-137
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• 2017

Cotton is the major fiber crop in Pakistan that accounts for 2% of total national gross domestic product (GDP). After picking of cotton, the dry stalks are major organic waste that has no fate except burning to cook food in villages. Present research focuses use of cotton stalks as feedstock for biochar production, its characterization and effects on soil characteristics. Dry cotton stalks collected from agricultural field of Bahauddin Zakariya University, Multan, Pakistan were combusted under anaerobic conditions at $450^{\circ}C$. The physicochemical analysis of biochar and cotton stalks show higher values of % total carbon, phosphorus and potassium concentrations in biochar as compared to cotton stalks. The concentration of nitrogen was decreased in biochar. Similarly biochar had greater values of fixed carbon that suggest its role for carbon sequestration and as a soil amendment. The fourier transformation infrared spectroscopic spectra (FTIR) of cotton stalks and biochar exposed more acidic groups in biochar as compared to cotton stalks. The newly developed functional groups in biochar have vital role in increasing surface properties, cation exchange capacity, and water holding capacity, and are responsible for heavy metal remediation in contaminated soil. In a further test, results show increase in the water holding capacity and nutrient retention by a sandy soil amended with biochar. It is concluded that cotton stalks can be effectively used to prepare biochar.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.3
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• pp.343-350
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• 2015

Cocoa pod is among the by-products of cocoa (Theobroma cacao) plantations. The aim of this study was to apply a number of treatments in order to improve nutritional quality of cocoa pod for feeding of ruminants. Cocoa pod was subjected to different treatments, i.e. C (cocoa pod without any treatment or control), CAm (cocoa pod+1.5% urea), CMo (cocoa pod+3% molasses), CRu (cocoa pod+3% rumen content) and CPh (cocoa pod+3% molasses+Phanerochaete chrysosporium inoculum). Analysis of proximate and Van Soest's fiber fraction were performed on the respective treatments. The pods were then subjected to an in vitro digestibility evaluation by incubation in rumen fluid-buffer medium, employing a randomized complete block design (n = 3 replicates). Further, an in vivo evaluation of the pods (35% inclusion level in total mixed ration) was conducted by feeding to young Holstein steers (average body weight of $145{\pm}3.6kg$) with a $5{\times}5$ latin square design arrangement (n = 5 replicates). Each experimental period lasted for 30 d; the first 20 d was for feed adaptation, the next 3 d was for sampling of rumen liquid, and the last 7 d was for measurements of digestibility and N balance. Results revealed that lignin content was reduced significantly when cocoa pod was treated with urea, molasses, rumen content or P. chrysosporium (p<0.01) with the following order of effectiveness: CPh>CAm>CRu>CMo. Among all treatments, CAm and CPh treatments significantly improved the in vitro dry matter and organic matter digestibility (p<0.05) of cocoa pod. Average daily gain of steers receiving CAm or CPh treatment was significantly higher than that of control (p<0.01) with an increase of 105% and 92%, respectively. Such higher daily gain was concomitant with higher N retention and proportion of N retention to N intake in CAm and CPh treatments than those of control (p<0.05). It can be concluded from this study that treatment with either urea or P. chrysosporium is effective in improving the nutritive value of cocoa pod.

• Journal of Digital Convergence
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• v.16 no.2
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• pp.251-259
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• 2018

This study aimed to identify the risk factors for cardiovascular disease (CVD) among age groups using the Framingham risk score (FRS). The research design used was a cross sectional descriptive study using the Sixth Korean National Health and Nutrition Examination Survey from 2013-2015. Data from 5211 men, between the ages of 30-74 was analyzed. After adjusting for age, the result of logistic regression analysis showed that obesity (OR=2.51 95% CI=2.05-3.07), physical inactivity (OR=1.71, 95% CI=1.39-2.10), heavy alcohol drinking (OR=1.33, 95% CI=1.09-1.62), and dietary fiber intake (OR=0.99, 95% CI=0.98-0.99) were presented as predictors of CVD. Obesity was considered to be a particularly important predictor of CVD for young and middle-aged men. This result will be used for developing intervention relating to lifestyle modification for young and middle-aged men.

• Korean Journal of Optics and Photonics
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• v.5 no.4
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• pp.499-504
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• 1994

Ti-doped BSG (borosilicate glass) soot films on the silicone substrate have been deposited in the mixture of $SiCl_{4}$, TMB, $TiCL_{4}$ by flame hydrolysis deposition technique. The soot films are melted to form integrated fine glass films. We can fabricate thick films of serveral $10{\mu}m$ with deposition rate,more than $0.5{\mu}m$/min. Refractive index difference of BSG films are increased to more than 0.3% as function of the amount of Ti dopant. As a result of the process an optical waveguide which is simmilar with dimmension and refractive difference of optical fiber is produced. $BCl_{3}$ is widely used for B dopant, but we abtained the good results by the use of TMB in place of $BCl_{3}$. The melting point of silica soot glass is reduced to $1200^{\circ}C$ increasing B dopant. From FTIR analysis $B_2O_3$ content up to about lOmol% in BSG films. films.

• Journal of the Korean Society of Clothing and Textiles
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• v.30 no.2 s.150
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• pp.316-325
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• 2006

The colors of apparel are getting more important to give the differentiated character on fiber and fabrics. This study was to extract the favorable colors that become to facial color types. Research was carried out to classify the facial colors into several similar facial color groups. With JX-777, 2 points of face: forehead and cheek, were measured and classified into 3 facial color types. Sample size was 418 Korean adult males and other 15 of new males subjects. New chosen 3 subjects who had the classified facial color types, wore silver gown and black hat on his head to minimize the interaction of the clothe color an hair. The 40 standardized color samples were used to extract the favorable colors. 187 respondents answered the degree of becomingness of color samples on 3 facial color types. Data were analyzed by K-means cluster analysis, ANOVA and Duncan multiple range test using SPSS Win. 12. Findings were as follows: 1. 418 subjects who had YR colors were classified into 3 kinds of facial color groups. Type 1 was 4.59YR 5.89/5.12, Type 2 was 5.61 YR 5.41/4.79 and Type 3 was 4.38YR 6.49/4.89 respectively. 2. Favorable colors for Type 1 were 2 colors that belonged to ' a ' group from among colors that were divided into a, b, c group and 18 colors that belonged to ' a ' group from among colors that were divided into a, b group by Duncan post hoc test. 3. Type 2 showed that this type had many unfavorable colors. Unfavorable colors were 16 colors that belonged to ' c ' by Duncan test. 5. Favorable colors for Type 3 were 14 colors that belonged to ' a ' from among colors that were divided into a, b, c and 16 colors that belonged to ' a ' from among colors that were divided into a, b by Duncan test.

• Journal of the Korean Society of Clothing and Textiles
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• v.27 no.11
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• pp.1318-1329
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• 2003

The purpose of this study was to examine the effects of the structural characteristics of men's suit fabrics on the texture image and the preference, and to analyze the relationship between the preference and the practical sales ratio. In addition, the texture images and the preference of fabric and jackets made of the same fabrics were compared. As specimen, jackets for men's suit of 2002' S/S and their fabrics were collected. Questionnaires composed of 22 sensibility related and 21 fabric image related adjectives were developed. For the subjective evaluation of the texture image, both jackets and fabric samples were tested. Tests were performed with 100 female subjects in clothing department and apparel industry. For the objective evaluation, structural characteristics such as fiber contents, yarn twist, fabric count, thickness and weight were analyzed. Total Hand Value were calculated from mechanical properties determined by the KES-FB system. Factor analysis showed sensibilities were classified into 6 categories; "surface roughness", "weight", "density", "stiffness", "elasticity" and "wetness". Fabric images were classified into 4 categories; "classic", "original", "practical", and "stuffy". Depending on the method to show the specimen to the subjects, whether it is suit or fabric, statistically significant differences were observed with a number of adjectives for sensibilities and fabric images. The results of THV of KES did not agree with the preference of subjects, which suggests that we should be careful when using the KES system, which was developed for Japanese people. Price was considered to be another factor besides the texture image that influenced on purchase.

• Journal of the Korean Society of Clothing and Textiles
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• v.20 no.1
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• pp.228-238
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• 1996

The purpose of this study was to evaluate the effect of chacteristics of knit fabrics on the microclimate of the skin simulating system. To determine the effect of characteristics of knit fabrics, vapor state of sweat pulse was simulated in the closed system. Different contents of fibers such as cotton, wool and polyester with different yarn size and knit types were chosen for specimens. The changes of humidity and temperature of air layer in the simulated systems were measured. Buffering indices, $K_d$ and $\beta_r$, were determined by considering $\alpha_p, \DeltaP_{max}, t_{max}, and tan\beta$. Physical properties of knit fabrics such as thickness, porosity, air resistance and moisture vapor transport were measured. Results showed that vapor pressure of wool was lower than cotton or polyester This was attributed to the hydrophilicity of wool which absorbed moisture rather quickly and retained in the knit fabric. The time to decrease vapor pressure was faster for polyester than cotton or wool. As a result, $K_d$ was in the order of wool> polye, item> cotton. $\beta_r$ of wool was rower than cotton or polyester due to its lowers porosity and slower desorption rate. For the yarn size, $K_d$ was in the order of 80's> 60's> 30's; thinner and lighter yarn showed better water vapor transport property. For knit type, buffering capacity of single jersey was better than interlock knit fabric. Statistical analysis showed that the air permeability was the most influential factor far the water vapor transport properties.

• Journal of Sensor Science and Technology
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• v.6 no.2
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• pp.95-105
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• 1997

A new open-loop signal processing technique of digital phase tracking is known to have a Potential to solve the problems in the open-loop processor such as limited dynamic range, dependence on the optical intensity fluctuations, and dependence on gain fluctuations of signal path. But new problems with digital phase tracking must be solved before it can be a useful signal processing method. In this paper, barriers to the success of the digital phase tracking such as harmonics content, phase difference, amplitude variations of the phase modulation(PM) signal, bandwidth limit of the signal path, and the implementation of the mixer, are pointed out and their effects on the performance of the signal processor are analyzed to calculate the requirements of the signal processor for $1{\mu}rad$-grade FOG.