• KSTLE International Journal
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• v.3 no.2
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• pp.90-94
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• 2002

A press shoe is an element of a machine for squeezing water from wood pulp in the field of manufacturing paper. This is used to compress the pulp enveloped by felt sheet with a large roller. The squeezing farce is made by hydraulic pressure. The press shoe has a mechanism similar to a partial hydrostatic bearing. The pressure profile between press shoe and roller affects their squeezing ability, and partial peak pressure can tear the wet pulp. The curvature of the surface of press shoe varies to reduce the peak pressure and increase the mean pressure simultaneously, Therefore, the prediction of pressure distribution considering partially changed curvature of hydrostatic bearing is very important far designing the press shoe. In this study, the difference formulation of Reynolds equation far partial hydrostatic bearing is derived by direct numerical method and a computer program to calculate the pressure distribution is developed. We investigate the effect of partially changed curvature of bearing surface on the pressure distribution. Other design parameter far hydrostatic bearing such as depth of pocket and relative velocity are also studied.

• Journal of Korean Foot and Ankle Society
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• v.12 no.1
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• pp.41-46
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• 2008

Purpose: This study was designed to evaluate characteristics of foot pressure distribution with or without partial prosthetic foot in transmetatarsal amputee. Materials and Methods: The subjects were 9 transmetatarsal amputees. Foot pressures were measured at hallux, the $1^{st}-5^{th}$ metatarsal head (MTH), mid-foot, condyle area by F-scan system in amputated or contralateral foot during active walking. Results: In amputated foot, mean peak pressure was greatest in midfoot without prosthetic foot but it was greatest in hindfoot with prosthetic foot. In unaffected foot, although mean peak pressure was higher in hallux, and $1-5^{th}$ MTH compared to amputated foot, it was greatest in hind foot both with and without prosthetic foot. However, in unaffected foot, mean peak pressure significantly decreased in hallux and $5^{th}$ MTH after wearing the prosthetic foot. There was a significant difference in mean peak pressure in hallux and $5^{th}$ MTH between amputated and unaffected foot after wearing prosthetic foot. However, other region had no significant difference with or without prosthetic foot between feet. Conclusions: The use of partial prosthetic foot tends to shift weight bearing from the heel area to forefoot and could significantly reduce hind foot peak pressure and redistributed to peak pressure. The partial prosthetic foot can also offer the peak pressure to reduction both amputated foot and unaffected foot and help to toe off during walking.

• Journal of the Korean Institute of Electrical and Electronic Material Engineers
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• v.14 no.12
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• pp.1008-1015
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• 2001

Thin films of vanadium oxide(VO$\_$x/) have been deposited by r.f. magnetron sputtering from V$_2$O$\_$5/ target in gas mixture of argon and oxygen. The oxygen/(oxygen+argon) partial pressure ratio is changed from 0% to 8%. Crystal structure, chemical composition, bonding, optical and electrical properties of films sputter-deposited under different oxygen gas pressures are characterized through XPS, AES, RBS, FTIR, optical absorption and electrical conductivity measurements. V$_2$O$\_$5/ and lower oxides co-exist in sputter-deposited films and as the oxygen partial pressure is increased the films become more stoichiometric V$_2$O$\_$5/. The increase of O/V ratio with increasing oxygen gas pressure is attributed to the partial filling of oxygen vacancies through diffusion. It is observed that the oxygen atoms located on the V-O plane of V$_2$O$\_$5/ layer participate more readily in the oxidation process. With increasing oxygen gas pressure indirect and direct optical band gaps are increased, but thermal activation energies are decreased.

• Bulletin of the Korean Chemical Society
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• v.20 no.9
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• pp.1031-1034
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• 1999

Tin oxide films have been grown employing the chemical vapor deposition technique under reduced pressure conditions using tetramethyltin as the precursor and oxygen as the oxidant. An activation energy derived for the deposition reaction under representative deposition conditions has a value of 89±3 kJ mol-1, suggesting a typical kinetic control. Deposition rates of tin oxide films exhibit a near first order dependence on tetramethyltin partial pressure and a zeroth order dependence on oxygen partial pressure. This study provides the first quantitative information about the growth kinetics of tin oxide films from tetramethyltin by the cold-wall low-pressure chemical vapor deposition.

• Nano
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• v.13 no.10
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• pp.1850124.1-1850124.12
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• 2018

$TiO_2$ films were deposited from oxygen/titanium tetraisopropoxide (TTIP) plasmas at low temperature by Helicon-PECVD at floating potential ($V_f$) or substrate self-bias of -50 V. The influence of titanium precursor partial pressure on the morphology, nanostructure and optical properties was investigated. Low titanium partial pressure ([TTIP] < 0.013 Pa) was applied by controlling the TTIP flow rate which is introduced by its own vapor pressure, whereas higher titanium partial pressure was formed through increasing the flow rate by using a carrier gas (CG). Then the precursor partial pressures [TTIP+CG] = 0:027 Pa and 0.093 Pa were obtained. At $V_f$, all the films exhibit a columnar structure, but the degree of inhomogeneity is decreased with the precursor partial pressure. Phase transformation from anatase ([TTIP] < 0.013 Pa) to amorphous ([TTIP+CG] = 0:093 Pa) has been evidenced since the $O^+_2$ ion to neutral flux ratio in the plasma was decreased and more carbon contained in the film. However, in the case of -50 V, the related growth rate for different precursor partial pressures is slightly (~15%) decreased. The columnar morphology at [TTIP] < 0.013 Pa has been changed into a granular structure, but still homogeneous columns are observed for [TTIP+CG] = 0:027 Pa and 0.093 Pa. Rutile phase has been generated at [TTIP] < 0:013 Pa. Ellipsometry measurements were performed on the films deposited at -50 V; results show that the precursor addition from low to high levels leads to a decrease in refractive index.

• Journal of the Society of Naval Architects of Korea
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• v.44 no.6
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• pp.666-674
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• 2007

It is very important to estimate static squeezing pressure distributions for lining material of sterntube after bearing at dry dock stage since the maximum squeezing pressure value can be one of the significant characteristics representing coming navigation performances of the propulsion system. Moderate oil film pressure between lining material and propulsion shaft is also essential for safe ship service. In this paper, Hertz contact theory is explained to derive static squeezing pressure. Reynolds equation simplified from Navier-Stokes equation is centrally differentiated to numerically obtain dynamic oil film pressures. New shaft alignment technology of nonlinear elastic multi-support bearing elements is also used in order to obtain external forces acting on lining material of bearing. For 300K DWT class VLCC with synthetic bush of sterntube after bearing, static squeezing pressures are calculated using derived external forces and Hertz contact theory. Optimum partial slope of the after bush is presented by parametric shaft alignment analyses. Dynamic oil film pressures are comparatively evaluated for partially bored and unbored after bush. Finally it is proved that the partial slope can drastically reduce oil film pressure during engine running.

• Bulletin of the Korean Chemical Society
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• v.28 no.9
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• pp.1477-1484
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• 2007

Artificial neural networks (ANNs), for a first time, were successfully developed for the prediction partial molar heat capacity of aqueous solutions at infinite dilution for various polar aromatic compounds over wide range of temperatures (303.55-623.20 K) and pressures (0.1-30.2 MPa). Two three-layered feed forward ANNs with back-propagation of error were generated using three (the heat capacity in T = 303.55 K and P = 0.1 MPa, temperature and pressure) and six parameters (four theoretical descriptors, temperature and pressure) as inputs and its output is partial molar heat capacity at infinite dilution. It was found that properly selected and trained neural networks could fairly represent dependence of the heat capacity on the molecular descriptors, temperature and pressure. Mean percentage deviations (MPD) for prediction set by the models are 4.755 and 4.642, respectively.

• Journal of the Semiconductor & Display Technology
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• v.20 no.2
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• pp.82-86
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• 2021

In this study, we investigated the oxygen partial pressure effect of ITO films for electrodes of oxide-based Thin-Film Transistor (TFT). Firstly, we deposited single ITO films on the glass substrate at room temperature. ITO films were prepared at the various partial pressures of oxygen gas 0-7.4% (O₂/(Ar+O₂)). As increasing oxygen on the process of film deposition, electrical properties were improved and optical transmittance increased in the visible light range (300-800 nm). For the electrode of TFT, we fabricated a TFT device (W/L=1000/200 ㎛) with ITO films as the source and drain electrode on the silicon wafer. Except for the TFT device combined with ITO film prepared at the oxygen partial pressure ratio of 7.4%, We confirmed that TFT devices with ITO films via FTS system operated as a driving device at threshold voltage (V_th) of 4V.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.6 no.1
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• pp.31-36
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• 2000

180g of fermented soy paste and 150g of red pepper paste were packaged in glass jars of 232 mL with different conditions of active packaging and then stored at $13^{\circ}C$ for about 170 and 128 days, respectively. During the storage, package atmosphere, surface color, pH, acidity and microbial flora were monitored to see the effect of packaging conditions. Test packaging conditions include package equipped with $Ca(OH)_2\;as\;CO_2$ absorber, package with pinhole and closed control one. Closed control packages of soypaste and red pepper paste showed the increased $CO_2$ partial pressure, the decreased $O_2$ partial pressure and the constant $N_2$ partial pressure to produce high pressure buildup with storage. The paste packages with $Ca(OH)_2$ maintained relatively low $CO_2$ partial pressure and thus the package pressure close to normal atmospheric pressure for initial storage period of 70 days. The packages with air pinhole channel had the partial pressures of $O_2\;and\;N_2$ decreased with storage time, while $CO_2$ partial pressure first increased to a maximum and then slowly decreased thereafter Without any pressure increase the packages with pinhole gave the lowest quality changes possibly due to the effect of package atmosphere, but it had problem of mold contamination and growth for soy paste after 120 days. There were no difference in microbial flora between the packages after about 70 day storage.

• The Journal of Korean Academy of Prosthodontics
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• v.21 no.1
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• pp.59-66
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• 1983

Distal extension partial dentures are supported by both the relatively rigid teeth and the resilient mucosa. So impression techniques of residual alveolar ridge in case of distal extension partial denture have particular importance in order to broad distribution of the masticatory force. McLean recognized the need for recording the tissues supporting distal extension partial denture base in functional form to equalize the resilient and non-resilient support, and this was called functional impression. Many investigators proposed various techniques of the functional impression for a distal extension partial denture, but only a little studies were performed about displacement of soft tissue under distal extension partial denture base. The purpose of this study is to investigate the amount of vertical displacement of the soft tissue under distal extension partial denture base by different functional impression techniques. Impression techniques used were Z.O.P. Impression, Selective Tissue Placement Impression, Functional Relining Impression. Measurement of the vertical displacement of soft tissue were made with Depth Gauge and Measuring Platform. A Anatomic Impression was used as a control. The results were tested statistically using 3 way ANOVA and Scheffe test. The followings were the results obtained from this study. 1. The greatest amount of soft tissue displacement was observed in the center of the retromolar pad. 2. No significant differences were found between the crest of alveolar ridge and the buccal shelf area. 3. The greatest soft tissue displacement was observed in Functional Relining Impression using Iowa wax, and the least displacement was observed in Selective Tissue Placement Impression using murcaptan rubber base. 4. No significant differences were found between finger pressure and biting pressure in Z.O.P. Impression, but greater displacement was observed by biting pressure than finger pressure in Functional Reling Impression.