• Journal of Pharmaceutical Investigation
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• v.19 no.4
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• pp.173-178
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• 1989

Drug release rates from copolymer hydrogels were controlled by their hydrophilic-hydrophobic balances. As a model copolymer hydrogel, poly(acrylamide-co-styrene) was synthesized at different monomer composition. Release mechanisms of propranolol-HCI from the copolymer matrices were investisated. Swelling rates of the copolymer hydrogels retarded as their hydrophobicity increased. Swelling kinetics of the copolymer hydrogels regulated drug release rates via polymer relaxation controlled release mechanisms. Zero order drug release could thus be achieved within certain periods.

• Biomolecules & Therapeutics
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• v.12 no.2
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• pp.57-61
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• 2004

In the present study, we investigated whether lipopolysaccharide induce mucin release and erythro-mycin affect basal and adenosine triphosphate-induced (stimulated mucin release, from airway goblet cells. Confluent primary hamster tracheal surface epithelial cells were metabolically radiolabeled and chased for 30 min or 24 hr in the presence of varying concentrations of lipopolysaccharide or erythromycin to assess the effects on $^3H$-mucin release. The results were as follows : 1) Lipopolysaccharide failed to induce mucin release, 2) Erythromycin showed no effect on both basal and stimulated mucin release during 30 min of 24 hr treatment period. We conclude that lipopolysaccharide and erythromycin can not affect mucin release by direct acting on airway mucin-secreting cells.

• Magazine of the Korean Society of Agricultural Engineers
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• v.30 no.2
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• pp.95-104
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• 1988

This study refers to the development of a hydrologic model simulating daily inflow and release rates for inigation reservoirs. A daily - based model is needed for adequate operation of an irrigation reservoir sufficing the water demand for paddy fields which is closely related to meteorological conditions. And the objective of this study is to develop a reservoir release rate model and then to calibrata the parameters. The release rates model considers daily water demands , water supply for transplanting, minmum release for maintaining canal flow, and maxirnun and regular flooding depth for determining effective rainfall on paddy fields. Each of the factors in the model was regarded as a lumped pararuter representing the average condition of a whole irrigated area. The water demand was estimated form the potential evapotranspiration by Penman method, the effective rainfall, and the infiltration on paddy fields. The release model was found to be capable of adequately simulating daily reservoir releases based on meteorological data.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2003.10a
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• pp.539-542
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• 2003

In South Korea, flooding is controlled with large or small reservoirs scattered spatially over the territory. Because recent unexpected hard-rain events requires more flood control capacities, the pre-release system is considered with the most economical alternative. In this case time and volume of discharge should be determined by the simulation. But, existing pre-release simulation system has the problem of specificity. Therefore, GASS is considered to estimate the pre-release time and volume with different configurations of pre-release system. This paper shows that pre-release simulation system could be constructed with arranging GASAtmosphere, GASWatershed, Reservoir, Gate components using GASS. It is also shows that GASS could be used as a foundation for constructing pre-release simulation system that is easy to use and is flexible to reflect the changing configurations of reservoir systems.

• Proceedings of the KSPS conference
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• 2003.10a
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• pp.43-49
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• 2003

This study reveals the perceptual role of stop release burst to Koreans' recognition of POA(place of articulation) and voicing in the English word-final stops. 10 Korean subjects participated in a perception experiment wherein the stimuli are prepared on the basis of the amount of acoustic information, which includes the release burst. The result shows that i) release burst plays an important role in the recognition of POA in the order of velar, alveolar, and bilabial stops, and ii) the release burst more enhances the correct recognition of voiceless stops than that of voiced stops. This result leads us to conclude that the role of stop release burst differs with respect to the POA and voicing of the stops, and it is possibly related to the different intensity of release in voicing and in each POA.

• Archives of Pharmacal Research
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• v.17 no.4
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• pp.240-243
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• 1994

Release rates of flurbiprofen from transdermal gels made of poloxamer 407 were evaluated using a membraneless diffusion cell in order to study the effects of formulation variables on flurbiprofen release such as poloxamer 407 (17.5-25%) drug (0.1-1.0%), ethanol (10-20%), PG or PEF 300 (5-15%) concentrations and gel pH(3-7). Isopropyl myristate was employed as a receptor medium for the drug released from the gel. The diffusion coefficient of flurbiprofen decreased linearly as the amount of poloxamer 407 and the drug in the gel increased. The release rate of flurbiprofen was gel increased. The The addition of more ethanol in the gel increased the drug release, resulting from the increase of the thermodynamic activity of the drug in the aqueous phase of the gel. However, the concentration effects of PG and PEG 300 on the release rate of flurbiprofen were negligible over the concentration range used.

• The Journal of Korean Academy of Orthopedic Manual Physical Therapy
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• v.5 no.1
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• pp.53-58
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• 1999

PURPOSE; The main purpose of physical therapy is to minimize patient's pain. So this study aimed at evaluating the effect of PAS release applied to tender points in reducing pain of musculoskeletal lesion persons. METHOD; The PAS (capsicum plaster) Release applied at 48 tender points to relieve and assessment pain threshold by Harold Gottlieb's pain scale that was composed of Negligible sensation 4.00, Mild sensation 3.00, Moderate sensation 2.00, Severe sensation 1.00. RESULT; Results show that PAS release was 84.6% effect in achieving a gradual decrease of pain sensitivity at the tender points where it was applied, suggestion a cumulative analgesic effect through sessions. CONCLUSION; This study suggests that PAS release applied to tender points can be effective in relieving soft tissue pain through theses have not become asymptomatic, all referred significant pain relief(p <0.05) after study and at the end of PAS release therapy.

• Journal of Pharmaceutical Investigation
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• v.24 no.3
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• pp.139-144
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• 1994

The effect of some formulation variables on the release rate of famotidine, a $H_2$ receptor antagonist, from cellulose matrices containing hydroxypropylcellulose (HPC) in different ratios and types was investigated. The effects of tablet shape and compression pressure on dissolution rate of famotidine were studied. And the effect of the pH of dissolution media was also studied. Increase in the ratio of polymer to drug decreased the release rate of famotidine. Increase of the polymer viscosity also decreased the release rate. The release rate of famotidine was dependent on the pH of dissolution media. The release rate of drug was not much dependent on the compression pressure but dependent on the tablet shape and/or surface area. Consequently, the release rate of famotidine can be modified by changing the HPC contents, types of polymers with different viscosity grades or using appropriate fillers.

• Convergence Security Journal
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• v.8 no.4
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• pp.121-126
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• 2008

It is of great practical interest to decide when to stop testing a software system in development phase and transfer it to the user. This decision problem called an optimal release policies. In this paper discussed to specify an optimal release policies. In this paper, propose an optimal release policies of the life distribution applied Erlang distribution of special pattern of Gamma distribution. In this paper, discuss optimal software release policies which minimize a total average software cost of development and maintenance under the constraint of satisfying a software reliability requirement. From Sensitivity Analysis, make out estimating software optimal release time.

• Journal of the Korean GEO-environmental Society
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• v.14 no.10
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• pp.17-27
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• 2013

This paper explores stress release induced by unloading in dry sand. A series of model tests were carried out to measure stresses developed in testing sand during loading and those released during unloading for different boundary conditions. It was found that stress in the sand increased linearly with applied load. At the onset of unloading, almost no stress release was observed. Significant stress release took place when the shear stress in the sand induced by unloading exceeded the frictional resistance and caused movement of sand particles. The initiation and the magnitude of stress release depend on the stress condition prior to unloading, the decrease of external load, and also the frictional resistance in sand. A new conceptual stress-release model was next developed based on the model test results by considering the fundamental frictional behavior of granular materials.