• International Journal of Highway Engineering
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• v.8 no.2 s.28
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• pp.87-93
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• 2006

To evaluate the deformational characteristics of subgrade soils, four subgrade samples in Korea were tested using the RC and TS tests with various dry unit weight and water content. Both the maximum modulus and normalized modulus reduction curves of subgrade soils were affected by the dry unit weight. The normalized modulus was decreased about 20% with increasing of relative compaction of 5%. It was founded that the variations of modulus of subgrade soils in Korea were over 40% with water content variation of $\pm$2%, and those effects can be estimated by exponential model. However, the normalized modulus reduction curves were almost identical and independent of water content. It was also founded that confining pressure, loading frequency, dry unit weight, and water content have an affect on modulus of subgrade soils independently. Therefore, it can be considered that those effects are independent variables.

• Journal of the Korean Wood Science and Technology
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• v.31 no.5
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• pp.57-64
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• 2003

Small cherry specimens modified with acetic anhydride and formaldehyde vapor phase were weathered by outdoor exposure and accelerated conditioning in a climate chamber. The effects of the chemical modification were evaluated by measuring their weight percentage gains (WPG), hygroscopicity and color differences before and after weathering. The average WPGs of the 72 hour acetylated and formaldehyde-treated specimens were 8.1 and 15.7%, respectively. After outdoor exposure for more than 2 months, the acetylated specimens lost weights by only 1.5%, but the formaldehyde-treated did much more than the formers. It was revealed that acetylation reduced the hygroscopicity and discoloration of wood while formaldehyde treatment didn't. Moreover the longer is the formaldehyde treatment time the more degraded after weathering. It was concluded that the vapor-phase acetylation could be applied for improving the dimensional stability of old wooden blocks.

• Journal of the Korean Society of Tobacco Science
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• v.1 no.2
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• pp.127-137
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• 1979

Three factors affecting cigarette weight, tobacco shreds length(cut width 0.9mm), moisture content and filling grower were studied for domestic brands. The results were obtained as follows. 1. When the moisture contents war법 changed by one per cent consecutively. filling power of tobacco shreds and cigarette weight were changed by 3.9 - 7.9 per cent for the former and by 5.7 - 7.6 per cent for the later. The longer the length of tobacco, shreds, the wider are the changing radios, and vice versa. 2. At constant moisture content (12 %), filling Power and cigarette weight were varied by 3.8- 22.8 per cent and by 2.9-29.4 per cent respectively due to the fluctuation of tobacco shreds length, The range of this variation was increased by reducing moisture content , and was decreased by increasing the moisture content. 3. The higher the blending ratio of shreds longer than 2 mm, the lower are the cigarette weights. 4. The operation standard weight of domestic brands was found 1- 9 per cent higher compared with the observed optimal cigarette weight in this study.

• Applied Biological Chemistry
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• v.29 no.2
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• pp.148-158
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• 1986

The effects of sodium nitrite on weight loss, pH, color development, color and lipid oxidation for the cooking of longissimus pork muscle were studied. Higher cooking temperature and grinding of sample increased the extent of weight loss, but sodium nitrite lowered it. Cooking decreased pH and sodium nitrite lowered the level of decrease in pH. Sodium nitrite developed color and controlled discoloration with higher lightness. The content of malonaldehyde was generally accelerated by cooking, but was considerably reduced at higher cooking temperature and for longer cooking time. Sodium nitrite acted as an antioxidant but the antioxidant effect decreased with increasing cooking temperature and time. Cooking reduced the extent of each lipid on the whole. Phosphatidyl choline and phosphatidyl ethanolamine were the major phospholipids of pork, and their contents decreased during cooking. The major fatty acids in total lipids were oleic acid and palmitic acid. Those in phospholipids were linoleic acid ana palmitic acid. The high level of polyunsaturated fatty acids and essential fatty acids in phospholipids decreased during cooking. Sodium nitrite had an antioxidant effect on polyunsaturated fatty acids in both total lipids ana phospholipids.

• Korean Journal of Agricultural Science
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• v.20 no.2
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• pp.167-180
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• 1993

Most of small size diesel engines are widely used with the same size and weight flywheel in the levels of 6.0kW and 7.5kW. This study was conducted to obtain basic data which affect the engine performance of the power tiller. The flywheel weight was considered as a major factor in this research. Basically, fuel consumption ratio, motoring loss, torque, vibration and mechanical efficiency of the engine were measured and analyzed on four levels of flywheel weight, 32.2, 29.4, 26.2 and $24.2kg_f$, respectively. Results were obtained as follows: 1. The weights of flywheel were $23.7kg_f$ from design program of JSME and $24.5kg_f$ from ASME and SAE design criteria. Therefore, the flywheel weight of $32.2kg_f$ might be reduced about $8kg_f$ in 7.5kW engine. 2. The rated outputs of 6.0kW and 7.5kW engine were actually 7.43kW and 7.85kW, respectively. When flywheel weight was reduced from $32.2kg_f$ to $24.2kg_f$, outputs were increased from 7.43kW to 7.70kW in 6.0kW engine and from 7.85kW to 8.25kW in 7.5kW engine. 3. When the flywheel weight was reduced from $32.2kg_f$ to $24.2kg_f$, fuel consumption ratio was decreased from 300.8 to 296.8g/kW-hr in 6.0kW engine and also from 313.6 to 312.8g/kW-hr in 7.5 kW engine, respectively. 4. When the flywheel weight was reduced from $32.2kg_f$ to $24.2kg_f$, mechanical efficiency of engine was increased from 76.1% to 76.8% in 6.0kW engine and also from 76.7% to 77.0% in 7.5kW engine, respectively. 5. When the flywheel weight was reduced from $32.2kg_f$ to $24.2kg_f$, vibration was decreased at X-axis and Z-axis in 6.0kW engine, however, slightly increased at Y-axis in 6.0kW engine and at all axes in 7.5kW engine. 6. When the flywheel weight was reduced from $32.2kg_f$ to $24.4kg_f$ motoring loss was decreased from 2.33kW to 1.75kW in 6.0kW engine and also from 2.46kW to 1.84kW in 7.5kW engine.

• Applied Biological Chemistry
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• v.42 no.3
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• pp.223-228
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• 1999

The storage effects of satsuma mandarin(Citrus unshiu Marc. var. miyagawa) by humidity control during storage; 90% relative humidity (RH) and 85% RH at $3^{circ}C$, and room temperature were investigated. After 98 days' storage, weight losses were 3.40% for 90% RH, 6.92% for 85% RH, and 11.87% for room temperature storage. Decay ratio was increased rapidly from 3.87% on 98 days' to 48.75% on 126 days' storage for 90% RH. Soluble solids and flesh ratio were declined gradually, but the differences were not significantly. Firmness of fruits was continuously reduced during storage, especially on room temperature storage by the softening of the fruits. Acid content and vitamin C were gradually reduced during storage. Coloration was continuously progressed on room temperature, compared to cold storage. In order to keep freshness of the fruits, optimum storage period of early variety of Satuma mandarin was regarded for 100 days at $3^{circ}C$, 85% RH on the basis of sensory evaluation and chemical compositions.

• Food Science and Preservation
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• v.9 no.4
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• pp.362-368
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• 2002

Physicochemical properties of garlic bulb during storage with different cutting treatments were estimated. Garlic harvested in early June was used in this experiments. Various physicochemical factors of garlic bulb such as weight loss rate, rotten rate, sprouting rate, moisture content, reducing sugar content and total pyruvate content were investigated. Bulbs with roots, bulb without roots and bulb with stem length of l cm, 3 cm, 5 cm were stored at 2$\^{C}$ for eight months. The weight loss increased sharply after 8 months for all treatments. Weight loss occurred most severely in treated garlics with bulbs with 5 cm stem length and progressed steadily at low rates in bulbs with 1 cm stem length. Also, less decay and internal sprouting were observed in bulbs with 1 cm stem length. Cutting treatments of roots were not significant for internal sprouting. Incidence of other chemical properties of bulbs, contents of total sugar, reducing sugar and pyruvic acid were not significant statistically. Moisture contents of treated garlics was remarkably reduced in longer leaving stems. As a result, top-clipped leaving stems fur long, seemed to have a beneficial effect on physicochemical properties of garlic stored at 2$\^{C}$ for 8 months possibly due to reduced weight loss, rotten decaying and sprouting rates. Utilization of such results in the processing industry can be effective.

• Korean Journal of Food Science and Technology
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• v.29 no.1
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• pp.57-64
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• 1997

The research was investigated to determine the effect of organic acids or packaging methods (PA) either alone or in combination on the quality of Aster scaber during storages. The Aster scaber was treated with organic acids and PA, and stored at different temperature $(1\;and\;5^{\circ}C)$. Total plate counts, weight loss, color change, and sensory evaluation were evaluated. Both organic acid treatments, PA, and combined treatment had little effect on the inhibition of total plate counts compared to the control (non-treatment). Organic acid treatments showed less weight reduction compared to the control and nitrogen treated package had the least weight reduction, but the combined treatments showed less weight reduction than organic acid treatments or packaging method alone. Organic acid treatments were little different from the control on color change, but nitrogen packages had the least color change, whereas combined treatments were a little reduced, but little different compared to the control or nitrogen packages. The nitrogen packages showed better effects on the sensory evaluation compared to other treatments and the results of sensory evaluation were consistent with that of weight reduction and color change, but not in total counts. All these results showed better effects in $5^{\circ}C$ rather than $1^{\circ}C$.

• Journal of the Korean Chemical Society
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• v.29 no.5
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• pp.543-551
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• 1985

A new class of polyhydrazones has been synthesized by the solution polycondensation from equimolecular amounts of aromatic dialdehydes such as para, meta, ortho-phthal aldehyde, 5,5'-methylene-bis-salicyl aldehyde (PPTA, MPTA, OPTA, MBSA) and dihydrazides, 5,5'-methylene-bis-salicylic dihydrazide (MBSDH), terephthalic dihydrazide (TDH), sebacic dihydrazide (SDH) in DMF-$CH_3COOH$ solution. The solubility characteristics, spectral, and thermal properties of the synthesized polyhydrazones and their metal chelates were also studied. These polyhydrazones and their metal chelates except the polyhydrazone prepared from OPTA-MBSDH were generally insoluble in common organic solvents. The thermogravimetric analysis of polyhydrazones showed 10% weight losses at 250∼350$^{\circ}$C and residual weight at 500$^{\circ}$C were 32.5∼62.5%. The decomposition temperature of higher relatively, and the metal chelates decrease in the following orders; Zn(II)-IIa > Ni(II)-IIa > Co(II)-IIa > Cu(II)-IIa.

• Korean Journal of Food Science and Technology
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• v.28 no.2
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• pp.220-225
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• 1996

Quarri green peppers were stored at $3^{\circ}C$ and $25^{\circ}C$, and capsaicin, ascorbic acid, chlorophyll, free sugars and surface color of the peppers were measured for 35 days of storage. Capsaicin and dihydrocapsaicin of quarri green peppers decreased during storage. The changes were bigger at $25^{\circ}C$ storage than at $3^{\circ}C$. Weight loss and decaying rate of the peppers were affected most by the increasing storage period and temperature. Ascorbic acid diminished remarkably at the beginning of storage period. Free sugars and chlorophyll decreased gradually during storage. Browning of quarri green peppers progressed slowly during storage not in pericarps but in seeds.