• Computers and Concrete
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• v.33 no.5
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• pp.573-594
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• 2024

This article presents a research study, with both laboratory and field tests, of a deep foundation in a markedly anisotropic medium. Particularly it has focused on the evaluation of the behavior of a pile, one meter in diameter, embedded in a rocky environment with difficult conditions, in the Flysch of the Spanish city of San Sebastián. To carry out the research, the site of a bridge over the Urumea River was chosen, which was supported by pre-excavated reinforced concrete piles. 4 borings were carried out, by the rotation and washing method, with continuous sampling and combined with flexible dilatometer tests. In the field, an Osterberg load test (O-cell) was performed, while in the laboratory, determinations of natural moisture, natural unit weight, uniaxial compressive strength (UCS), point load strength (PLS), compressive wave propagation velocity (V_c) and also triaxial and direct shear tests were carried out. The research results indicate the following: a) the empirical functions that correlate the UCS with the PLS are not always linear; b) for the studied Flysch it is possible to obtain empirical functions that correlate the UCS with the PLS and with the V_c; c) the bearing capacity of the studied Flysch is much greater than if it is evaluated by different load capacity theories; d) it is possible to propose an empirical function that allows evaluating the mobilized shear strength (τ_m), as a function of the UCS and the displacement relative of the pile (δ_r).

• Journal of Marine Bioscience and Biotechnology
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• v.16 no.1
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• pp.19-25
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• 2024

To verify the color change in dried laver postproduction during the heating process, chromaticity elements were compared via a spectrophotometer across various heating conditions within the visible light spectrum. In general, the moisture reduction rate increased with rising temperature and time. Surface image comparisons revealed an expanded area of light reflection on the heat-treated dried laver sample due to surface roughening from shrinkage. No statistically significant differences in chromaticity values were observed in the measurements of brightness (L^*), redness (a^*), and yellowness (b^*). Reflectance spectrum measurements in the visible light region confirmed high reflectance under red wavelength conditions. In particular, a significant increase in reflectance at 700 nm compared with untreated samples was noted. The correlation between the increase in 700 nm reflectance of dried laver samples and heating conditions ranged from 0.7471 to 0.7793, suggesting its potential use as an indicator for comparing color changes in dried laver based on heating conditions.

• Journal of Korean Society of Forest Science
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• v.33 no.1
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• pp.1-32
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• 1977

This study has been made to find out more effective way of vegetation establishment on severely denuded forest land from the viewpoint of soil moisture regimes. Various environmental factors were measured to estimate soil moisture conditions of different sites. Soil moisture influence on growth of over vegetations, water requirement and drought resistance were analyzed. The efficiency of water use was also reckoned at different fertility levels and different soil moisture conditions. This research is composed of field experiment and green house experiment. Field experiment includes height growth, survival and coverage analysis of cover vegetations (Robinia pseudoacacia L., Lespedeza bicolor Turcz, Arundinella hirta Tanaka var. ciliare Koidzumi.) with 4 fertility level treatments on 3 slopes (Steep: $37^{\circ}$, Moderate: $25^{\circ}$, Gentle; $17^{\circ}$) during dry season (1 April-30 June) and wet season (1 July-10 September). At the same time temperature, relative humidity and precipitation were measured to understand the environmental changes. Soil moisture conditions were measured with soil moisture meter with 24 soil cells. Green house experiment comprised height, fresh weight and dry weight measurements of cover vegetations with 4 fertility levels and 3 moisture conditions for 70 days. The results extracted from experiments are as follews. 1. Cover vegtations have 3 patterns of water requirement at the early stage of growth. a) Robinia type has high water requirement and weaker drought resistance. b) Lespedeza type has low water requirement and stronger drought resistance. c) Arundinella type has moderate water requirement and weaker drought resistance. 2. The vegetations have different optimum fertility levels in different soil moisture supply condition. a) Robinia needs a low fertility level in dry condition and a high level in wet condition. b) Lespedeza needs only low fertility level in all conditions. c) Arundinella needs a low fertility level in dry condition and a high level in wet condition. 3. The efficiency of water use (Water/1g dry weight) by fertility levels is different from one another. Robinia and Arundinella have a good efficiency at low fertility level in dry condition and at high fertility level in wet condition. Lespedeza has a good efficiency at low fertility level in all conditions. 4. $P_2O_5$ requirement of Robinia and Lespedeza is high, but that of Arundinella is low. Soil moisture condition has a great influence on $P_2O_5$ absorption in dendued forest land. Once Vegetations are established on suitable sites with optimum fertitity level according to different moisture condition, even the small amount of soil water in denuded land can he used with high efficiency and the effect of fertility treatment can be maximized.

• Korean Journal of Food Science and Technology
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• v.31 no.1
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• pp.45-53
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• 1999

Physicochemical and sensory characteristics of cooked rice during warm-keeping with different temperature $(70,\;75,\;80^{\circ}C)$ and period (0, 6, 12, 24, 48 hr) were investigated. As the storage temperature increased, sweet flavor, glossiness, moistness, taste and moisture content decreased but off-flavor, color and sensory and texturometric hardness increased. This trend was significant with storage period. As the storage time and temperature increased, yellowness(b) measured by Hunter color difference meter increased while lightness(L) and whiteness decreased. Degree of retrogradation of cooked rice during storage increased, particularly did in cooked rice stored at $80^{\circ}C$. Cooked rice stored at 70 and $75^{\circ}C$, 6 hr had the least changes in flavor and appearance but more changes in them longer storage time. Cooked rice stored at $80^{\circ}C$ had rapid changes in flavor, appearance and texture at initial state of storage. These results showed that the changes in moisture content of cooked rice stored at various conditions had the most important effect upon sensory characteristics of cooked rice.

• Journal of the Korean Wood Science and Technology
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• v.16 no.4
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• pp.48-53
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• 1988

This study was carried out to investigate the effects of pressing time and spreading amount, moisture content, gap-distance with butt to butt joint and adhesives on bonding strength in manufacturing the laminated wood with Pitch pine (Pinus rigida). The results obtained were as follows: 1) The pressing time of 12 hours, 10 kilogram per square centimeter of pressure and 200 gram per square meter of spreading amount were required to reach over 50 kilogram per square centimeter (block shear strength) in manufacturing the laminated wood by aqueous vinyl urethane adhesive. 2) The bonding strength decreased with the increase of moisture content of wood. The block shear strength, however, showed over 100 kilogram per square centimeter when the strength test was carried out after air-drying the laminated wood in high moisture content (30-70%). 3) Regardless of direction of load, every flexural property decreased with the increase of gap-distance with butt to butt joint. However, little of every flexural property was changed at 0.5 millimeter of joint-gap distance. The flexural property of vertically laminated wood (perpendicular to glue line to load direction: 1) showed more than that of horizontally laminated wood (parallel to glue line to load direction: //). 4) Among five adhesives used at this experiment, the bonding strength of aqueous vinyl urethane adhesive was the highest in dry bond and wet tests.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.7 no.4
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• pp.98-109
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• 2004

This study was conducted to develop revegetation methods for the restoration of the steep slopes by recycling of bark compost and mushroom media. In general, bark compost and mushroom media can be used as soil media for the restoration works, because they can increase infiltration of rainfall and give enough porous to breathe and elongate for the root growth as well as environmental value. This experiment was carried out to know the effect of soil media composed by different ratio of mushroom media for the restoration of steep rock-exposed slopes, and to certificate how soil media(PEC) will be effective to germinate and grow for native plants. The main results of the study are summarized as follows; 1. In percent coverage, the soil media PEC1 is more valuable than PEC2. The seed mixtures recommended by Government of Transportation and Construction can be used at PEC1 and PEC2, but it will be more useful if the total amount of seed are reduced and seed mixtures are altered in a direction of native plants. 2. The soil media is under 20 mm tested by Yamanaka Hardiness Tester which is available for the seed germination and growth. 3. The surface cracks are not occurred in PEC1 and PEC2, but more than 30 cracks per 1 square meter are occurred at soil media which is constructed by normal soil-seed-fertilizer hydro-seeding methods. 4. The soil moisture contents are over 20 percent level during 15 day. Such moisture content in soil media will be effective for the plant growth. By using Terra-Control, PEC can maintain enough soil moisture. 5. The eroded soils from $60^{\circ}$ slopes by artificial rainfall with the intensity of 20 mm/hr in one day after seeding are estimated under 1%. By the results of erosion test, it comes to the conclusion that soil media of PEC can be adapted at steep rock exposed slopes.

• Journal of the Korean Society of Food Culture
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• v.7 no.3
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• pp.213-222
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• 1992

This investigation was undertaken for the purpose of studying the quality and acceptability during storage at room or refrigerator temperature of Yackwa containing waxy rice flour substituted for 0,10,30,50,70% of the wheat flour. The storage periods were 0,15,30 and 45 days. Chemical composition, composition of fatty acids, and value, and peroxide values of Yackwa were measured. Sensory evaluation was done by a panel of 5 judges majoring in food and nutrition. The evaluation was repeated 4 times. Objective evaluation was done by rheometer and color difference meter. Chemical composition of Yackwa were $5.9{\sim}6.8%$ for moisture, $3.43{\sim}4.09%$ for crude protein, $22.35{\sim}27.65%$ for crude fat, $0.27{\sim}0.31%$ for ash, $15.6{\sim}18.4%$ for fructose, $10.6{\sim}13.7%$ for glucose, $0.34{\sim}1.0%$ for sucrose, and $0.79{\sim}2.37%$ for maltose, respectively. Fatty acid contents of Yackwa were $10.54{\sim}10.73%$ for palmitic acid, $4.12{\sim}4.18%$ for stearic acid, $25.8{\sim}26.9%$ for oleic acid, $51.6{\sim}52.1%$ for linoleic acid, and $0.27{\sim}0.34%$ for linolenic acid, respectively. Acid value and peroxide value of Yackwa during storage showed little change. As a result of sensory evaluation for Yackwa made various levels of waxy rice flour, there were no significant differences in most of characteristics between the samples supplemented with waxy rice flour to 30% of wheat flour at 0.01% level. By the color difference meter, the value of L (lightness) and b (yellowness) were increased by increasing the amounts of waxy rice flour, however, there were no significant differences at 0.1% level between the samples supplemented with waxy rice flour to 30% of wheat flour, on the other hand, the value of a (redness) was decreased by increasing the amount of waxy rice flour. In the textural characteristics, brittleness, and chewiness were increased by increasing the amounts of waxy rice flour, and by lengthening the storage period, on the other hand, resilience and cohesiveness showed vice versa. In the correlation coefficient between sensory characteristics and mechanical characteristics, overall acceptability in sensory evaluation correlated significantly with cohesiveness, chewiness, and the values of L, a, and b in mechanical test in most of samples(p<0.001).

• Journal of the Korean Wood Science and Technology
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• v.36 no.6
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• pp.1-12
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• 2008

A series of the studies on the applied physical properties of domestic species have been conducted last three years. Liriodendron tulipifera, Betula costata, Paulownia coreana were examined on sorption property, thermal property, electric property, acoustic property. Because the same apparatus and experimental procedures were used for all species, their results can be easily comparable. The experiments for sorption property were conducted with 80 mesh wood powder and resulted in their EMC's and sorption isotherms. The thermal conductivity and diffusivity, and electric resistance and volumetric electric resistivity were measured with a thermal-wire device and a high electric resistance meter. The differences of the thermal and electric properties between quarter-and flat-sawn specimens were observed, which was partially attributed to their anatomical differences. An acoustic measurement system was used to evaluate dynamic MOE and internal friction. This paper provides the useful fundamental data for designing a wood structure, correcting a portable resistance-type moisture meter, and acoustic properties of wood.

• Journal of the Korean Wood Science and Technology
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• v.36 no.4
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• pp.1-10
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• 2008

A series of the studies on the applied physical properties of domestic species have been conducted last three years. Pinus koraiensis and Larix kaempferi were two of the three species examined for the first year. Because the same apparatus and experimental procedures were used for all species, their results can be easily comparable. The experiments for sorption property were conducted with 20- and 80-mesh wood powder and resulted in their EMCs and sorption isotherms at various RH conditions. The thermal conductivity and diffusivity, and electric resistance and volumetric electric resistivity were measured with a thermal-wire device and a high electric resistance meter. The differences in the thermal and electric properties between quarter- and flat-sawn specimens were observed, which were partially attributed to their anatomical differences. An acoustic measurement system was used to evaluate dynamic MOE and internal friction. This paper provides the useful fundamental data for designing a wood structure, correcting a portable resistance-type moisture meter, and acoustic properties of wood.

• Journal of the Korean Wood Science and Technology
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• v.36 no.3
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• pp.70-84
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• 2008

A series of the studies on the applied physical properties of domestic species have been conducted last three years. Pinus densiflora was one of the three species examined for the first year. Because the same apparatus and experimental procedures were used for all species, their results can be easily comparable. The experiments for sorption property were conducted with 20- and 80-mesh wood powder and resulted in their EMC's and sorption isotherms at various heating conditions. The thermal conductivity and diffusivity, and electric resistance and volumetric electric resistivity were measured with a thermal-wire device and a high electric resistance meter. The differences of the thermal and electric properties between quarter- and flat-sawn specimens were observed, which was partially attributed to their anatomical differences. An acoustic measurement system was used to evaluate dynamic MOE and internal friction. This paper provides the useful fundamental data for designing a wood structure, correcting a portable resistance-type moisture meter, and nondestructive testing wood.