• Magazine of the Korean Society of Agricultural Engineers
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• v.22 no.3
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• pp.60-74
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• 1980

Soil-cement mixtures involve problems in it's durability in grain size distribution and mineral composition of the used soils as well as in cement content, compaction energy, molding water content, and curing. As an attempt to solve the problems associated with durability of weathered granite soil with cement treated was investigated by conducting tests such as unconfined compression test, it's moisture, immers, wet-dry and freeze-thaw curing, mesurement of loss of weight with wet-dry and freeze-thaw by KS F criteria and CBR test with moisture curing on the five soil samples different in weathering and mineral composition. The experimental results are summarized as follows; The unconfined compressive strength was higher in moisture curing rather than in the immers and wet-dry, while it was lowest in freeze-thaw. Decreasing ratio of unconfined compressive strength in soil-cement mixtures were lowest in optimum moisture content or in the dry side rather than optimum moisture content with freeze-thaw. The highly significant ceofficient was obtained between the cement content and loss of weight with freeze-thaw and wet-dry. It was possible to obtain the durability of soil-cement mixtures, as the materials of base for roads, containing above 4 % of cement content, above 3Okg/cm$_2$ of unconfined compressive trength with seven days moisture curing or 12 cycle of freeze-thaw after it, above 100% of relative unconfined compressive strength, 80% of index of resistance, below 14% of loss of weight with 12 cycle of wet-dry and above 1. 80g/cm$_2$ of dry density.

• Journal of Korean Society for Atmospheric Environment
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• v.19 no.2
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• pp.217-229
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• 2003

The amounts of nitrogen and sulfur deposited in the region of the Yellow Sea in both dry and wet forms were estimated by using the measurement data published in tile literature during tile past 10 years. In the estimation of dry deposition, concentrations at ground stations including those at a station on the Chinese side and concentrations from shipboard and aircraft measurements were used as well as deposition velocities. Wet deposition flux was determined at ground stations on the Korean side either by taking the flux data themselves or by calculating them from precipitation data in the literature. The dry deposition flux over the Yellow Sea was much greater than those China was confirmed from the fact that the total amount summing wet and dry depositions exceeded the emission amount from Korea. Dry deposition was principally made in the gaseous form due to a larger deposition velocity. Nevertheless, since the deposition velocity over water was smaller than that over the ground, dry deposition of oxidized nitrogen was smaller than wet deposition. As a whole, wet depositions of nitrogen and sulfur were 2.3 and 1.9 times 1arger than corresponding dry depositions, respectively.

• Asian-Australasian Journal of Animal Sciences
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• v.14 no.10
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• pp.1450-1459
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• 2001

These experiments were conducted to investigate the effects of different feeding and processing methods of diets on performance, morphological changes in the small intestine and nutrient digestibility of growing-finishing pigs. One-hundred fifty growing pigs ($Yorkshire{\times}Landrace{\times}Duroc$; initial body weight of $23.33{\pm}0.75kg$) and one-hundred twenty finishing pigs ($Yorkshire{\times}Landrace{\times}Duroc$; initial body weight of $59.22{\pm}0.56kg$) were used in Exp. 1 and Exp. 2, respectively. Pigs were grouped on the basis of body weight and gender, and randomly allotted into 6 different treatments with 5 replications in each treatment in a $2{\times}3$ factorial arrangement. Treatments were 1) dry feeding with a mash diet (DM), 2) dry feeding with a pelleted diet (DP), 3) dry feeding with an expanded crumble diet (DEC), 4) dry/wet feeding with a mash diet (WM), 5) dry/wet feeding with a pelleted diet (WP), and 6) dry/wet feeding with an expanded crumble diet (WEC). In Exp. 1 (growing phase), there was no significant difference in average daily gain (ADG) and average daily feed intake (ADFI) among treatments during the entire experimental period, but feed conversion ratio (FCR) was significantly (p<0.05) improved in pigs fed pelleted diets regardless of feeding method. FCR was best in pigs fed a DP diet and worst in pigs fed a WM diet. Pigs fed a pelleted diet showed a 6.2% or 4.0% improvement in FCR compared with those fed a mash diet or an expanded crumble diet. Water disappearance was not significantly affected by dry/wet feeding or feed processing. Significant differences in villus height were not found among treatments, but villus height tended to be improved by dry/wet feeding. Dry/wet feeding or feed processing did not affect crypt depth. Digestibilities of calcium and phosphorus were significantly (p<0.05) improved in pigs fed an expanded crumble diet compared with pigs fed mash diets. Especially, pigs fed a WEC diet digested 8.1% more P than those fed a DM diet. Feed cost per kg weight gain (FCG) tended to be increased by dry/wet feeding rather than dry feeding. In Exp. 2 (finishing phase), ADG and ADFI were not significantly different among treatments, but a significant difference in FCR was found among feed processing forms. The best FCR was obtained in pigs fed a pelleted diet. Pigs fed a DP diet showed a 11.3% improvement compared with those fed a DEC diet. Water disappearance was significantly (p=0.0408) decreased by feeding the mash diet. However, water disappearance was not affected by dry/wet feeding during the finishing period. The villus height and crypt depth were not significantly different among treatments. However, crypt depth tended to be decreased by dry/wet feeding at the mid part of the small intestine. Fat digestibility was improved by dry feeding rather than dry/wet feeding, and was improved by 4.8% by feeding pellet diets compared with expanded crumble diets. Except for carcass grade, carcass characteristics were not significantly (p<0.05) different among treatments. Carcass grade was the best in pigs fed a WP diet. Feed cost per kg weight gain (FCG) was significantly decreased in pigs fed a pelleted diet compared with those fed an expanded crumble diet, and tended to be decreased by dry/wet feeding. In conclusion, these studies suggest that feeding the pelleted diet to growing-finishing pigs can be beneficial in terms of FCR and production cost. Dry/wet feeding can be helpful for the maintenance of villus height, but may not be reflected in improved growth performance or reduction of production costs.

• Journal of Korean Ophthalmic Optics Society
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• v.13 no.4
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• pp.59-63
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• 2008

Purpose: The purpose of this study is to understand a relation of water content measurement with two different method, water removal method and dry method. Methods: 72 hydrogel contact lens containing various water content (ranged from 47% to 58%) were measured by the gravimetric method at 20$^{\circ}C$and 21% of the humidity. We weighed the dried test specimen at room temperature for 30 min after cooling. Results: In dry blotting method, the water content was measured to 47.43${\pm}$8.48%. The water contents was measured to 48.15${\pm}$8.36% with wet blotting condition. It was found that wet blotting method showed the higher water content of about 7% than dry blotting method. In water content with two dry methods, each of results was measured by 47.89${\pm}$8.06% and 49.56${\pm}$7.06%. In case of microwave method, the water content was measured significantly higher water content of about 1.67% than vacuum oven method. However, no statistical difference was found (p>0.05). Conclusions: In water removal method (Dry blotting method and Wet blotting method) to weigh hydrated test specimen, wet blotting method showed significantly higher water content than dry blotting method. Also in case of dry methods (vacuum oven and microwave) to weigh dry test specimen, water content of microwave method showed higher water content than vacuum oven method, but it should be noted that microwave oven method must be used carefully to measure accurateness on the specimen position and wave power.

• Proceedings of the Korean Geotechical Society Conference
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• 2006.03a
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• pp.111-120
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• 2006

Opening size of 3 types of geotextile were tested using dry and wet sieving methods to evaluate characteristics of test methods and to compare the test results. Judging from test results, dry sieving method is a poor test, having many problems causing many errors but a simple-quick test. Wet sieving method is a very specific test avoiding many of the problems of dry sieving such as electrostatic charges, trapping in the geotextiles and so on. However, one of wet sieving tests, KSK ISO12956, takes long time to complete a test and is too strict to handle loss of granular material. Generally, opening size of a geotextile by wet sieving test is smaller than that of dry sieving test. Especially, opening size by KSF 2126 which is one of wet sieving test but disused at present anymore is similar or smaller than that by KSK ISO12956 method.

• Journal of Korea Technical Association of The Pulp and Paper Industry
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• v.37 no.4 s.112
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• pp.26-31
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• 2005

The purpose of this study was to confirm paper strengthening properties with recently commercialized polyvinylamine. Because of its high cationic charge density, polyvinylamine has been investigated as a size retention and surface coating aids. In this study, we tried to confirm polyvinylamine as wet-end additives to improve dry and wet strength using LBKP and BCTMP pulps. As a result, we found improvement of dry and wet tensile properties of polyvinylamine with BCTMP were much better than LBKP condition. This phenomena could be explained that ionic bonding of cationic charge of polyvinylamine with abundant anionic substances of BCTMP was a very important factor to improve dry and wet strength of paper.

• Journal of the Korean Ceramic Society
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• v.31 no.1
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• pp.55-61
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• 1994

Mn-Zn ferrite powder was obtained by wet method that was to be coprecipitated the metal ions of Fe2+, Mn2+ and Zn2+ with alkali solution. The target composition of the ferrite powder was 52 mol% Fe2O3, 24 mol% MnO, and 24 mol% ZnO, that was based on the region of high permeability. And the other ferrite powder was prepared by the dry method that was to be mixed the metal oxides as the above chemical composition. The wet method was compared with dry method for the powder properties and the electromagnetic characteristics of sintered cores. The synthesized powder by wet method was smaller particle size, narrower particle distribution, and higher purity than that of dry method. The initial permeability of sintered sample prepared by the wet method was 14000~28000, on the other side, 9000~15500 in case of the dry method.

• Journal of Surface Science and Engineering
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• v.32 no.3
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• pp.253-256
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• 1999

Wet plating has been initiated and developed as a major surface finishing technology as of the long customized and highly productive process until now. As the external compression by virtue of the environmental preservation becomes stricter, there has been new move to adapt dry plating line instead of conventional wet plating one in domestic surface finishing industry. Dry plating, so-called, plasma surface technology has been developed in semiconducting industry and becomes a key technology to be useful as an alternative to wet plating in surface finishing industry. The historical progress of domestic surface finishing industry was outlined with the background on the adaptation of three dry plating processes-plasma spraying, plasma nitriding and ion plating. The present status of domestic industrial activity was covered on major alternative to wet plating.

• Nutrition Research and Practice
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• v.6 no.4
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• pp.366-374
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• 2012

In order to create a worker-friendly environment for institutional foodservice, facilities operating with a dry kitchen system have been recommended. This study was designed to compare the work safety and work environment of foodservice between wet and dry kitchen systems. Data were obtained using questionnaires with a target group of 303 staff at 57 foodservice operations. Dry kitchen facilities were constructed after 2006, which had a higher construction cost and more finishing floors with anti-slip tiles, and in which employees more wore non-slip footwear than wet kitchen (76.7%). The kitchen temperature and muscular pain were the most frequently reported employees' discomfort factors in the two systems, and, in the wet kitchen, "noise of kitchen" was also frequently reported as a discomfort. Dietitian and employees rated the less slippery and slip related incidents in dry kitchens than those of wet kitchen. Fryer area, ware-washing area, and plate waste table were the slippery areas and the causes were different between the functional areas. The risk for current leakage was rated significantly higher in wet kitchens by dietitians. In addition, the ware-washing area was found to be where employees felt the highest risk of electrical shock. Muscular pain (72.2%), arthritis (39.1%), hard-of-hearing (46.6%) and psychological stress (47.0%) were experienced by employees more than once a month, particularly in the wet kitchen. In conclusion, the dry kitchen system was found to be more efficient for food and work safety because of its superior design and well managed practices.

• Journal of Korean Society of Coastal and Ocean Engineers
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• v.15 no.2
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• pp.97-107
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• 2003

In order to evaluate the effect of dry-wet treatment on well developed tidal flats along the complex coastal line in the western part of Korean Peninsula, we adopted a finite element tidal hydrodynamic simulation model, ADCIRC incorporating newly suggested dry-wet option and applied it to Chonbuk coastal area and Keum river estuary. Model comparison with observed current data by RMS error in the Chonbuk area shows very good agreement within 1cm/sec of tidal velocity difference and 3％ of error to maximum tidal currents. However there is not seen any significant advantages in dry-wet treatment. For the tidal volume tests in the Keum river estuary, the differences are satisfied within 5％ nevertheless of dry-wet treatment but in a near cross section it marks over 20％. However both results are almost same in tidal residual tests. Thus it can be concluded that dry-wet option is not always necessary in the simulation of long-term dispersion analysis.