• Macromolecular Research
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• v.14 no.3
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• pp.331-337
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• 2006

In the present study we investigated the relationship between the morphology and mechanical properties of electrospun polysulfone (PSF)/polyurethane (PU) blend nonwovens, by using the electrospinning process to prepare three types of electrospun nonwovens: PSF, PU and PSF/PU blends. The viscosity, conductivity and surface tension of the polymer solutions, were measured by rheometer, electrical conductivity meter and tensiometer, respectively. The electrospun PSF/PU blend nonwovens were characterized by scanning electron microscopy (SEM) and with a universal testing machine. The SEM results revealed that the electrospun PSF nonwoven had a structure consisting of cross-bonding between fibers, whereas the electrospun PU nonwoven showed a typical, point-bonding structure. In the electrospun PSF/PU blend nonwovens, the exact nature of the point-bonding structure depended on the PU contents. The mechanical properties of the electrospun PSF/PU blend nonwoven were affected by the structure or the morphology. With increasing PU content, the mechanical behaviors, such as Young's modulus, yield stress, tensile strength and strain, of the electrospun PSF/PU blend nonwovens were by up to 80%.

• Journal of Forest and Environmental Science
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• v.29 no.1
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• pp.49-57
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• 2013

Malaysia possesses about 1.56 million ha of Peat Swamp Forest (PSF). The PSF safeguard enormous biological diversity, while providing crucial benefits for the sustainable development of human communities. Numbers of threatened plant species are associated with the PSF, including the commercially important Gonystylus bancanus timber. To prevent significant losses of biodiversity, it is important to manage the PSF for both biological conservation and sustainable use. Equally important is to restore all degraded PSF in an attempt to ensure the PSF ecosystem is suitable for the vegetation to grow and rehabilitate back to the normal condition. Prior to plan any forest restoration program, there is a need to properly map the degraded PSF in order to estimate the forest conditions and determine the vegetations status. Most of the time this need to be done at a landscape level and requires a technology that can provide accurate, timely and reliable information for the planner to make decision. This paper describes a study using geospatial technology in combination with ground survey to classify the degraded PSF in South East Pahang Peat Swamp Forest (SEPPSF), Malaysia, into different degree of vegetation classes. With map accuracy of about 83%, the technique proved to be useful in delineating the different degree of PSF degradation from which the information can be used to properly plan forest restoration program in the area. The final output which is in the form of map can be used in developing a Restoration Master Plan for the degraded PSF areas.

• Applied Chemistry for Engineering
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• v.7 no.5
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• pp.877-887
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• 1996

The ideal membranes for membrane-covered oxygen probes system should be selectively permeable for oxygen and chemically inert, and have good mechanical strength. Polysulfone(PSf) was selected to develop the membrane for membrane-covered oxygen electrodes system. PSf membranes have properties such as good reproducibility, good mechanical strength, chemical inertness, and high heat resistance. PSf membranes were cast from polymer solution on the glass plate at constant temperature, and casting solvents used were tetrahydrofuran(THF), methylene chloride, and N-methyl-2-pyrrolidone(NMP). Tricresyl phosphate(TCP) as plasicizer was added to PSf to increase the softness of membrane. The permeation characteristics were observed for pure oxygen and nitrogen through pure PSf membranes by variable volume method and membrane-covered electrode system. The permeability coefficients of oxygen and nitrogen measured by variable volume method were slightly decreased with increasing of upstream pressure. The permeation properties of PSf membrane using methylene choride as casting solvent were not affected by the PSf amount of polymer solution. The permeability coefficients of oxygen and nitrogen for PSf membrane containing TCP were very slightly lower than those for pure PSf membrane, but ideal separation factors were slightly higher. The flexibility of PSf membrane containing 2wt% TCP was better than that of pure PSf membrane. It was expected that this increase in flexibility would solve the difficulty of fixing the membrane to the cathode. The membrane-covered oxygen probes system was composed of anode, cathode and electrolyte. The type of the anode was Ag/AgCl half-cell, that of cathode was Ag, and the electrolyte was 4N KCl solution. The result of sampled current voltametry for PSf membrane showed the plateu region at -0.3V~-1.0V. The correlation coefficient of oxygen partial pressure versus current for PSf membrane was relatively high, 0.99949. It was concluded that PSf membrane was the good candidate for the membrane-covered oxygen probes system.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2010.11a
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• pp.417-418
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• 2010

• Membrane Journal
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• v.10 no.4
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• pp.192-197
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• 2000

Gas permeation and separation characteristics of ozone treated polysulfone (PSF) membranes were investigated. The PSF is one of the most widely used commercial membranes. Ozone treatment of the PSF membrane was performed for certain hours by continuously supplying 5 vol.% ozone-containing oxygen to the chamber, in which the membrane samples were charged. The permselectivity of PSF increased with ozone treatment time, and it was found that one and half hour was enough to ozone treatment. Increase in the selectivity of the membrane for He/$N_2$, HY$N_2$, O:J$N_2$, COJ$CH_4$ by ozone treatment was found to be due to decrease in the permeability of gases with larger molecular size such as $N_2$ and $CH_4$ The decrease in the permeability of gases with smaller molecular size was negligible. The increase in the selectivities of the PSF by ozone treatment would be due to decrease in the free volume of the polymer because of the oxygen complexes generated by the reaction between ozone and the polymer.

• Membrane and Water Treatment
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• v.7 no.2
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• pp.155-173
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• 2016

The present work has been focused on the development of polysulfone (PSf) ultrafiltration membrane via blending by sulfonated polyethersulfone (SPES) in order to permeability enhancement for ultrafiltration of cheese whey. In this regards, sulfonation of polyethersulfone was carried out and the degree of sulfonation was estimated. The effect of blend ratio on morphology, porosity, permeation and fouling of PSf / SPES membranes was investigated. Filtration experiments of whey were conducted for separation of macromolecules and proteins from the lactose enrichment phase. The morphology and performance of membranes were evaluated using different techniques such SEM, AFM, and contact angle measurements. The contact angle measurement showed that the hydrophilicity of membrane was increased by adding SPES. According to AFM images, PSf / SPES membranes exhibited lower roughness compared to neat PSf membrane. The water and whey flux of these membranes were higher than neat membrane. However, flux was decreased when the PSf / SPES blend ratio was 0/100. It can be attributed to pore size and morphology changes. Further, fouling parameters of PSf membrane were improved after blending. The blend membranes show a great potential to be used practically in proteins separation from cheese whey.

• Physical Therapy Rehabilitation Science
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• v.7 no.2
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• pp.83-87
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• 2018

Objective: The purpose of this study was to investigate the relationship between heart rate (HR), self-awareness of exercise intensity (rating of perceived exertion, RPE), and 5-meter walk test (5MWT) of persons affected by stroke during backward walking according to the preferred stride frequency (PSF), PSF+3 and PSF+6 conditions. Design: Cross-sectional study. Methods: A total of 11 persons with stroke (9 males, 2 females) participated voluntarily. All patients underwent backward walking under the PSF, PSF+3, and PSF+6 conditions in underwater and ground environments, and each condition was performed for 5 minutes. The HR, RPE, and walking speeds were measured during walking, and the measured values from underwater and ground environments were compared. Results: The HR and RPE in the ground environment were significantly increased (p<0.05), and although the 5MWT showed an increase in speed, it was not significant. The HR and RPE in the underwater environment were also significantly increased (p<0.05), however, although the 5MWT results was increased, it was not significant. The HR and RPE were significantly increased in the PSF+6 condition (p<0.05). Conclusions: The results of this study showed that backward gait training underwater can provide an appropriate exercise intensity for stroke survivors and suggests that exercises performed in an underwater environment is more effective compared to the ground environment.

• Journal of the Institute of Electronics and Information Engineers
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• v.49 no.11
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• pp.47-55
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• 2012

In this paper, we propose a method to reconstruct accurate 3D shape object by using multi-view images which are disturbed by motion blur. In multi-view deblurring, more precise PSF estimation can be done by using the geometric relationship between multi-view images. The proposed method first estimates initial 2D PSFs from individual input images. Then 3D PSF candidates are projected on the input images one by one to find the best one which are mostly consistent with the initial 2D PSFs. 3D PSF consists with direction and density and it represents the 3D trajectory of object motion. 야to restore 3D shape by using multi-view images computes the similarity map and estimates the position of 3D point. The estimated 3D PSF is again projected to input images and they replaces the intial 2D PSFs which are finally used in image deblurring. Experimental result shows that the quality of image deblurring and 3D reconstruction improves significantly compared with the result when the input images are independently deblurred.

• Proceedings of the Korean Society of Broadcast Engineers Conference
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• 1997.11a
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• pp.139-143
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• 1997

본 논문에서는 점확산함수(point spread function; PSF)의 추정을 기반으로 한 완전한 자동초점 시스템을 제안한다. 초점이 맞지 않은 영상의 정확한 PSF의 추정을 위해서, 입력 영상을 부영상으로 분할하고, 에지를 가진 부영상들의 계수함수 응답의 평균을 취한다. 초점이 맞지 않은 열화로 발생하는 PSF는 보통 영상이 물체와 배경간에 선형의 경계를 가지고 있다는 가정하에 에지의 방향을 따라 평균되어진 계단함수 응답의 차이를 따라 추정되어진다. 이렇게 예측된 PSF를 사용하여 영상복원 필터는 제한적 최소 제곱의 접근방법을 통해 구현되어진다.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.7
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• pp.974-981
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• 2002

Faba beans (vicia faba) (FB) and lupin seeds (Lupinus Albus) (LS) were dry roasted at three temperatures (110, 130, $150^{\circ}C$) for 15, 30 or 45 min to determine the effects of dry roasting on rumen degradation of crude protein and starch free organic matter ($^{PSF}OM$). Rumen degradation characteristics of $^{PSF}OM$ were determined by the nylon bag incubation technique in dairy cows fed 60% hay and 40% concentrate. Measured characteristics of $^{PSF}OM$ were undegradable fraction (U), degradable fraction (D), soluble fraction (S), lag time (T0), and the rate of degradation (Kd). Based on the measured characteristics, rumen availability ($RA^{PSF}OM$) and bypass $^{PSF}OM$ ($B^{PSF}OM$) were calculated. Dry roasting did not have a greater impact on rumen degradation characteristics of $^{PSF}OM$ (p>0.05). S varied from 32.1 (raw) to 30.0, 27.8, 30.8% (LS) and 15.4 (raw) to 14.4, 20.8, 20.9% (FB); D varied from 65.4 (raw) to 66.3, 66.9, 55.9% (LS) and 54.9 (raw) to 55.0, 51.0, 64.7% (FB); U varied from 2.6 (raw) to 7.3, 7.0, 7.7% (LS) and 29.7 (raw) to 30.6, 28.2, 14.4% (FB); Kd varied from 6.0 (raw) to 7.3, 7.0, 7.7% (LS) and 22.4 (raw) to 24.4, 21.1, 7.9% (FB); $B^{PSF}OM$ varied from 35.5 (raw) to 33.8, 36.6, 38.2% (LS) and 41.3 (raw) to 41.5, 39.7, 47.6% (FB) at 110, 130 and $150^{\circ}C$, respectively. Therefore dry roasting did not significantly affect $RA^{PSF}OM$, which were 353.7, 367.9, 349.6, 336.9 (g/kg DM) (LS) and 12.82, 127.0, 133.7, 117.1 (g/kg DM) (FB) at 110, 130 and $150^{\circ}C$, respectively. These results alone with our previously published reports indicate dry roasting had the differently affected pattern of rumen degradation characteristics of various components in LS and FB. It strongly increased bypass crude protein (BCP) and moderately increased starch (BST) with increasing temperature and time but least affected $^{PSF}OM$. Such desirable degradation patterns in dry roasted LS and FB might be beneficial to the high yielding cows which could use more dry roasted $^{PSF}OM$ as an energy source for microbial protein synthesized in the rumen and absorb more amino acids and glucose in the small intestine.