• 한국산업보건학회지
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• 제4권2호
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• pp.157-167
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• 1994

This study was conducted to analyze the relationship between the types of fiber and its content and the levels of airborne fiber concentrations at eight parking lots where sprayed insulation material was found on the walls and ceilings. Also this study was designed to find the relationship between the levels of airborne fiber concentrations and such variables as air current, humidity, total exhaust volume, surface condition of insulation material and building age. The results obtained were as follows : 1. No significant correlation was found between the levels of airborne tiber concentration and the building age, air current, humidity, total exhaust volume, space and the number of traffics. 2. A significant correlation was found between the levels of airborne fiber concentration and the MMMF content of the insulation material(r=0.7594). However, no significant correlation was found between the levels of airborne fiber concentration and total fiber content of insulation material. 3. The differences of the airborne fiber concentrations among Cateogory 1, 2 and 3 classified by the degrees of surface insulation material maintenance were very significant. 4. Two bulk samples contained 30% crodicolite and 1% anthophylite. The MMMFs, in all parking lots, included mineral wool, cellulose fiber, trace cellulose fiber, trace tiber glass and vermiculite. 5. The mean value and the range of airborne fiber concentrations at 8 parking lots were $0.0239{\pm}0.0095f/cc$ and 0.0054-0.0447 f/cc, respectively. The fiber concentrations of 35 out of 38 samples(92%) were over 0.01 f/cc which is the Environment Administration's recommended asbestos level for the underground space. This study suggests that most of building insulation materials used in Korea, contain MMMF and sometimes asbestos. Currently, MMMF pollution levels may exceed the Environment Administration's recommended level for underground space. It has been found that airborne fiber concentrations increased significantly with MMMF content and with the maintenance condition of surface material. Therefore, it is recommended that a proper management technique should be developed and immediately implemented since the conditions of surface material will be gradually deteriorated due to building age and usage. Since health hazards of the MMMF, similar to those of asbestos, are being gradually acknowledged, a proper management technique which is applicable to control total airborne fiber concentrations, both asbestos and MMMF, be developed and an acceptable indoor air standard be promulgated as early as possible.

• 한국초지조사료학회지
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• 제20권3호
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• pp.169-176
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• 2000

This experiment was carried out to investigate the effects of application levels of food waste compost andmineral nitrogen in 3 cuttings per annurn on the nutritive value and nutrient yields of orchardgrass (Dactylisglomerata L.). Annual food waste compost (FWC) and mineral nitrogen were applied at levels of 0, 10, 20,40 and 60 ton ha-', and 0, 90, 180 and 270 kg ha-', respectively. The contents of crude protein (CP, %) oforchardgrass were significantly higher at the application levels of 40 ton ha-' yr-' by FWC than those atapplication levels of 0 ton ha-' yr-' (p<0.05), the contents of neutral detergent fiber (NDF, %), acid detergentfiber (ADF, %) and hemicellulose were also higher in FWC applied plots, except for the FWC levels of 10and 60 ton ha-' yr-'. The contents of total digestible nutrient (TDN, %) and relative feed value (RFV) oforchardgrass were significantly higher at FWC levels of 10 and 60 ton ha-' yr-' than at levels of 0 ton ha"yr-'. Annual yields of CP and TDN were increased with increase the FWC levels. The highest contents ofCP of orchardgrass were obtained at 1st cut, NDF and ADF at 2nd cut. As the mineral nitrogen fertilizationwas increased, the contents of CP, NDF, ADF and hemicellulose of orchardgrass were significantly increased,but TDN and RFV were decreased. .Annual yields of CP and TDN of orchardgrass were significantlyincreased with increase the mineral nitrogen fertilization.(Key words : Food waste compost, Mineral nitrogen, Crude protein, Neutral detergent fiber, Acid detergentfiber)rgent fiber, Acid detergent fiber)

• 한국축산식품학회지
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• 제32권2호
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• pp.174-183
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• 2012

The effects of dietary fiber extracted from pumpkin (pumpkin fiber) on physicochemical properties, textural properties, and sensory characteristics of chicken frankfurters were investigated. Chicken frankfurter was supplemented with pumpkin fiber at levels of 0, 1, 2, 3, and 4%. Adding different levels of pumpkin fiber affected the proximate composition of the chicken frankfurters (p<0.05), except for protein content. In addition of different levels of pumpkin fiber influenced the physicochemical and textural properties of the chicken frankfurters (p<0.05). The yellowness, viscosity, and hardness were higher in chicken frankfurters samples containing pumpkin fiber than those in the control (p<0.05). The results showed that chicken frankfurter samples with higher pumpkin fiber levels had lower lightness values (p<0.05), as well as less cooking loss, emulsion stability, and lower color scores (p<0.05) compared to those control without pumpkin fiber treatment. The chicken frankfurters with 2% and 3% pumpkin fiber had higher overall acceptability than that of the control (p<0.05). The results show that adding pumpkin fiber produced acceptable chicken frankfurters and improved their quality characteristics.

• 한국식품영양과학회지
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• 제23권6호
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• pp.887-893
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• 1994

This study was undertaken to dtermine whether dietary fibers had an effect on postprandial plasma lipoprotein and liver lipid composition in rats. Each experimental diet ocntained 10 % dietary fiber by weight. All animals were sacrificed in postprandial state. Sodium alginate-fed animals has significantly lower plasma cholesterol, VLDL-, LDL-cholesterol, TG, and protein levels than did the fiber-free control group. In addition, liver cholesterol and TG concentrations were the lowest in sodium alginate -fed animals. There was no significant change in HDL-cholesterol levels among experimental groups. Cellulose-fed animals also have lower plasma cholesterol and TG levels than fiber-free controls, but liver TG concentrations were not different from those in fiber-free controls. This study demonstrates that dietary fiber included in the diet of rats is able to alter postprandial lipoportein cholesterol and TG, and that sodium alginate, a soluble fiber, was the most effective in lowering plasma and liver cholesterol and TG.

• Journal of Nutrition and Health
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• 제30권8호
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• pp.895-903
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• 1997

This study was performed to investigate the influence of dietray food from the three CHinese medicinal herbs(Mugwort, Dried organge peel and Duchung) on lipi d metabolism in rats. Male rats of Sprague-Dawley strain were divided into four dietary groups(Cellulose (CL), Mugwort(MW), Dried organge peel9OP), Duchung(DC)) after three weeks of hyperlipidemic dieting and were fed ad libitum each of the experimental diets for six weeks. The fiber sources of the experimental diets were prepared by drying and milling mugwort, orange peel, duchung and cellulose. Each of the Fiber sources was mixed into the diet to achieve 10g% levels of total dietary fiber. Levels of apparent fat absorption exhibited a significant decrease in the MW and DC groups. The OP group also showed a decreasing trend, but to a lesser extent. The levels of serum total lipid were not significantly different among the four experimental groups. Total serum cholesterol levels were significantly lower in the OP grop that in both the CM and MW group. Serum TG and LDL-cholesterol levels were significantly higher in the DL group than other groups. Serum HDL-cholesterol levels were significantly levels were significantly lower in the CL group than in the other groups. Total lipid and total cholesterol in liver were significantly higher in the CL group than in the other groups. Total lipid and total cholesterol in feces displayed a significantly increase in the MW and DC groups when compared with the CL group. The OP group also showed an increase compared to the CL group.

• 한국식품영양학회지
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• 제12권1호
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• pp.20-25
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• 1999

The study was conducted to investigate the effect of cholesterol and fiber on liver lipid metabolism in rats. Male Sprague Dawley rats were administrated 1% cholesterol and 0.25% sodium cholate to induce hypercholesterolemia and were fed diet containing three levels(0%, 5% and 10%) of cellulose and pec-tin respectively. The rats were sacrified after 5 weeks of feeding period. Net weight gain and feed ef-ficiency ratio were increased in 10% fiber groups as compared to those of 5% fiber groups. Feed intake did not show significancy by fiber kinds and levels. Liver and kidney weights tended to be decreased in proportion to level of fiber. Heart weight was lowered in 10% fiber groups as compared to that of 5% fi-ber groups. Liver triglyceride concentration was significantly increased in pectin groups. Total-free-cholesterol and cholesteryl ester concentrations in liver were significantly decreased by fiber and were decreased in proportion to level of fiver. Phospholipid concentration was significantly decreased by fiber and were decreased in proportion to level of fiber. Phospholipid concentration was significantly decreased in 5% cellulose group. the results indicate that 10% pectin may have beneficial roles in hypercholester-olemia.

• Geomechanics and Engineering
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• 제21권4호
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• pp.327-336
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• 2020

Conventional researches on the behavior of fiber-reinforced and unreinforced soils often investigated the failure point. In this study, a concept is proposed in the comparison of the fiber-reinforced with unreinforced sand, by estimating the strength and strength ratio at different levels of strain. A comprehensive program of laboratory drained triaxial compression test was performed on compacted sand specimens, with and without date palm fiber. The fiber inclusion used in triaxial test specimens was form 0.25%-1.0% of the sand dry weight. The effect of the fiber inclusion and confining pressure at 0.5%, 1.0%, 1.5%, 3.0%, 6.0%, 9.0%, 12%, and 15% of the imposed strain levels on the specimen were considered and described. The results showed that, the trend and magnitude of the strength ratio is different for various strain levels. It also implies that, using failure strength from peak point or the strength corresponding to the axial strain of approximately 15% for evaluating the enhancement of strength or strength ratio, due to the reinforcement, may cause hazard and uncertainty in practical design. Therefore, it is necessary to consider the strength of fiber-reinforced specimen at the imposed strain level, compared to the unreinforced specimen.

• Asian-Australasian Journal of Animal Sciences
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• 제3권4호
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• pp.353-361
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• 1990

A number of correlation and regression analyses were performed on data from apparent and true digestibility of amino acids at ileal and fecal level with finishing pigs, in order to investigate whether these amino acid digestibilities could be predicted with certainly degree on their fiber fractions content (chemical analysis). The data comprised 16 diets varying in 4 levels of crude fiber and from 4 fiber sources. The relationships between fiber fractions including crude fiber (CF), NDF, ADF lignin and cellulose contents on apparent and true digestibility of almost all amino acids in both ileal and fecal level were negative, except glutamine at fecal level. In apparent digestibility at ileal level, the correlations of fiber fractions were moderate (r of NDF = 0.53 to 0.63; ADF, 0.50 to 0.77; cellulose, 0.50 to 0.75), with an exception of CF content was relatively high (r of 0.58 to 0.81). The correlations to true digestibility of amino acids were weaker. In case of at fecal level, the higher correlation (negative) was found with NDF than CF content. Estimations of amino acids digestibility were performed using regression equation. The data showed that apparent digestibility of amino acids could be estimated for almost amino acids except arginine, threonine, valine and tyrosine at fecal level and phenylalaine, valine and glycine at ileal level. The best prediction at ileal and fecal level ($r^2=0.55-0.77$ and 0.52-0.76), respectively was obtained with NDF content. Prediction for true digestibility of amino acids, none of fiber fractions could be estimated for arginine, leucine and valine at all collection levels. At ileal level, CF could be used for most of amino acids except phenylalanine, glycine and praline; cellulose, only for lysine and methionine and NDF, only for proline. At fecal level, glutamine digestibility could be estimated only from CF and ADF content. The best predictor at ileal level was ADF content whereas at fecal level was NDF content. These results indicate that lignin content could not be used as predictor for all amino acids at both levels neither in apparent nor true digestibility.

• Journal of Nutrition and Health
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• 제28권2호
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• pp.107-114
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• 1995

These works were designed to examine the effects of dietary fiber sources and levels on lipid metabolism in rats fed high lard diet. Rats were divided into three($\alpha$-cellulose, polydextrose, carrageenan) groups and were fed with containing 6% fiber diet. Serum, liver and fecal lipid contents were examined after four weeks of dieting. Also, in order to investigate whether hypocholesterolemic effect of dietary fiber at 4 weeks is continued at 8 weeks, rats were fed with diets containing same sources with different levels of each dietary fiber and were sacrificed after eight weeks of dieting. Serum cholesterol in rats fed carrageenan diet and polydextrose diet were reduced compared with $\alpha$-cellulose-fed group at both four and eight weeks dieting. Liver cholesterol in both polydextrose-fed and carrageenan-fed group were lower than $\alpha$-cellulose-fed group. Fecal total group were increased compared with $\alpha$-cellulose-fed group. On the other hand, there was no significant difference between polydextrose-fed and carrageenan-fed group. On the basis of the results, it was suggested that the hypocholesterolemic effect of soluble fiber used in this study (polydextrose, carageenan) on rats was due to the inhibition of cholesterol absorption on the intestinal lumen and acceleration of cholesterol catabolism in the liver and enhancement of bile acids excretion. On the other hand, insoluble fiber($\alpha$-cellulose) showed no hypo-cholesterolemic effect.

• Structural Engineering and Mechanics
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• 제65권2호
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• pp.163-171
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• 2018

Plain concrete is a brittle material with a very low tensile strength compared to compressive strength and critical tensile strain. This study analyzed the dynamic characteristics of high-performance fiber-reinforced cementitious composites based on slurry-infiltrated fiber concrete (SIFCON-based HPFRCC), which maximizes the steel-fiber volume fraction and uses high-strength mortar to increase resistance to loads, such as explosion and impact, with a very short acting time. For major experimental variables, three levels of fiber aspect ratio and five levels of fiber volume fraction between 6.0% and 8.0% were considered, and the flexural strength and toughness characteristics were analyzed according to these variables. Furthermore, three levels of the aspect ratio of used steel fibers were considered. The highest flexural strength of 65.0 MPa was shown at the fiber aspect ratio of 80 and the fiber volume fraction of 7.0%, and the flexural strength and toughness increased proportionally to the fiber volume fraction. The test results according to fiber aspect ratio and fiber volume fraction revealed that after the initial crack, the load of the SIFCON-based HPFRCC continuously increased because of the high fiber volume fraction. In addition, sufficient residual strength was achieved after the maximum strength; this achievement will bring about positive effects on the brittle fracture of structures when an unexpected load, such as explosion or impact, is applied.