• Asian-Australasian Journal of Animal Sciences
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• v.18 no.2
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• pp.214-220
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• 2005

The study was conducted to compare the dry matter intake and digestibility of Atriplex halimus (AH) and Atriplex nummularia (AN) and determine the proper proportion of saltbushes for partial replacement of alfalfa hay in the diets of Awassi sheep. The foliage of AH and AN were hand-plucked, air-dried in shade and then chopped mechanically similar to alfalfa hay. Two trials were conducted separately to determine voluntary feed intake and digestibility of saltbush browse. In the first trial, fifteen 8 month old Awassi lambs were distributed into 3 equal groups, and each animal was housed in individual pen. Each group received one of three dietary treatments: chopped alfalfa hay (H), dried foliage of Atriplex nummularia or foliage of Atriplex halimus. In the second trial, twentyseven 12 months old Awassi male lambs were randomly selected, distributed into nine equal groups, and housed into metabolic crates. Each group of animals received one of nine dietary treatments: alfalfa hay, AN, AH and different proportions (25, 50 and 75%) of AN or AH mixed with alfalfa hay. Forage type had a significant (p<0.001) effect on dry matter intake (DMI) and growth rate of lambs of the voluntary feed intake trial. Lambs receiving the alfalfa hay diet showed high DMI and high growth rate compared to those fed the diets containing saltbush. In the digestibility trial, dietary treatments had significant (p<0.05) effect on DMI, dry matter digestibility (DMD) (p<0.01) and organic matter digestibility (OMD) (p<0.01). The inclusion of AN in the diet up to 50% had no significant effect on DMI and DMD, whereas the inclusion of AH above 25% reduced DMI, DMD and OMD. The treatments had significant (p<0.05) effect on water intake and on live weight changes of lambs. Except for the diet containing 25% of AN browse, all lambs fed diets containing the saltbushes exhibited loss in body weight. The nutritive value of Atriplex nummularia foliage is better than that of A. halimus and it is possible to replace up to 50% of alfalfa hay by A. nummularia without negative effects on intake and digestibility of dry matter.

• The Journal of the Korea institute of electronic communication sciences
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• v.13 no.3
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• pp.539-546
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• 2018

Recently, as the solar power generation market is rapidly increasing, interest is focused on research for minimizing the output of the solar cell module. The role of the power optimizer is important when inconsistencies occur in photovoltaic power generation. In the conventional system, centralized inverter method and microinverter method are mainly used. In this paper, we analyze the problem of power generation efficiency loss due to the incompatibility of existing system configuration methods. We also proposed a module - type power compensation method that can improve the mismatch caused by shading. The proposed module - based power optimizer is implemented and compared with the existing operation method. From the simulation result, it was confirmed that the efficiency of the proposed operation method is improved compared to the existing method.

• The Journal of Advanced Prosthodontics
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• v.9 no.5
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• pp.394-401
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• 2017

PURPOSE. The purpose of this study was to compare the optical properties of pre-colored dental monolithic zirconia ceramics of various thicknesses sintered in a microwave and those in a conventional furnace. MATERIALS AND METHODS. A2-shade of pre-colored monolithic zirconia ceramic specimens ($22.0mm{\times}22.0mm$) in 3 thickness groups of 0.5, 1.0, and 1.5 mm were divided into 2 subgroups according to the sintering methods (n=9): microwave and conventional sintering. A spectrophotometer was used to obtain CIELab color coordinates, and translucency parameters and CIEDE2000 color differences (${\Delta}E_{00}$) were measured. The relative amount of monoclinic phase ($X_m$) was estimated with x-ray diffraction. The surface topography was analyzed by atomic force microscope and scanning electron microscope. Statistical analyses were conducted with two-way ANOVA (${\alpha}=.05$). RESULTS. There were small interaction effects on CIE $L^*$, $a^*$, and TP between sintering method and thickness (P<.001): $L^*$ (partial eta squared ${{\eta}_p}^2=0.115$), $a^*$ (${{\eta}_p}^2=0.136$), and TP (${{\eta}_p}^2=0.206$), although higher $b^*$ values were noted for microwave sintering regardless of thickness. Color differences between two sintering methods ranged from 0.52 to 0.96 ${\Delta}E_{00}$ units. The $X_m$ values ranged from 7.03% to 9.89% for conventional sintering, and from 7.31% to 9.17% for microwave sintering. The microwave-sintered specimen demonstrated a smoother surface and a more uniform grain structure compared to the conventionally-sintered specimen. CONCLUSION. With reduced processing time, microwave-sintered pre-colored dental monolithic zirconia ceramics can exhibit similar color perception and translucency to those by conventional sintering.

• Korean Journal of Soil Science and Fertilizer
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• v.38 no.4
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• pp.218-221
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• 2005

The present study was investigated in the Chittagong hill forest of Bangladesh to assess the feasibility of ginger cultivation under multipurpose forest and fruit tree species. There were three treatments such as i) ginger grown under open field condition, ie. full sunlight (T1), ii) ginger grown under Gamar tree (spacing of $90{\times}90cm$ (T2) and iii) ginger grown under guava tree (spacing $180{\times}180cm$) tree (T3). The experiment was laid out in randomized block design (RBD) and each treatment was replicated three times. From data it was observed that some morphological parameters of ginger such as plant height, number of leaves per plant, leaf length and leaf breadth were higher in the treatments T2 and T3 as compared to the treatment T1. A positive and linear relationship was observed between the weight of rhizome and yield of ginger which caused the highest yield of ginger ($23.63Mg\;ha^{-1}$) under guava tree species at partial shaded condition in the T3 treatment ($180{\times}180cm$), whereas the lowest yield ($15.64Mg\;ha^{-1}$) was recorded in the T2 treatment when ginger was cultivated under Gamar tree species at closer spacing ($90{\times}90cm$). Therefore, it was revealed that partial shaded condition favoured the optimum growth and yield of ginger, whereas the dense shade from intensively planted tree species badly affected the dry matter production and yield of ginger.

• Journal of Bio-Environment Control
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• v.28 no.4
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• pp.311-321
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• 2019

Greenhouse farmers often use thermal screens to reduce greenhouse heating expenses during the winter, and for shade during hot, sunny days in the summer, as it is an inexpensive solution to temperature control relative to other available options. However, accurate measurements of their emitted and absorbed radiations are important for the selection of suitable screens that offer maximum performance. Material's ability to save energy is highly dependent on these properties. Limited studies have investigated the measurement of these properties under natural conditions, but they are only applicable to materials having partial porosities. In this work, we describe a new radiation balance method for determining emissive power and absorptive capacity, as well as reflectivity, transmissivity and emissivity of materials having complete and partial transparency by using pyrgeometer and net radiometer. In this study, four materials with zero porosity, were tested. The emissivity value of PE, LD-13, LD-15 and PH-20 was $0.439{\pm}0.020$, $0.460{\pm}0.010$, $0.454{\pm}0.004$, and $0.499{\pm}0.006$, respectively. All tested samples showed high emitted radiation as compared to absorbed radiation.

• Journal of Korean Society of Forest Science
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• v.97 no.6
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• pp.597-604
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• 2008

Recognizing the necessity of the development of ecologically sound silvicultural system for the mature Korean pine (Pinus koraiensis), this study was carried out to examine the invasion and growth of understory vegetation after partial cutting. In 1997, the age class VII Korean pine forest in the Experimental Forest of Kangwon National University was opened up about 50% by modified shelterwood cutting with site preparation to induce succeeding regenerations. After 10 years, plenty of hardwood have come to the stand, forming understory vegetation. The abundance and composition of understory vegetation was periodically investigated in the ten $10m{\times}10m$ permanent sample plots, estimating importance values, species diversity index and the distribution of diameter and height of the understory vegetation. Encouraged by canopy opening, the coverage of understory reached perfect closure, composed of 22 tree species and 20 shrub species in 2007. Morus bombycis occupied 29.6% of the total importance value and Cornus controversa was 17.0%, followed by Styrax obassia, Quercus aliena, Quercus mongolica, Acer mono, and Pinus koraiensis. In the year of 2000 the species diversity was highest as 2.547 with 26 tree species and deceasing thereafter, showing 2.220 with 22 tree species in 2007. As understory layer was thickly covered and got grow bigger, some shade intolerant species were disappeared, lowering species diversity. In 2007 the biggest tree was a Quercus aliena with 11.3 cm of DBH and the tallest tree was a Cornus controversa with 9.8m of height. The frequency distribution of number of trees by diameter and height classes formed the inverted-J-shaped curve, supposed to be typical uneven-aged stand.

• Food Science and Preservation
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• v.24 no.5
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• pp.658-665
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• 2017

The current study was performed to investigate the changes of bio-activities of Salicornia europaea (SE) depending on the different dry methods. The ethanol extracts were prepared from the freeze-drying SE (FD), hot-air drying SE (HD), and shade drying SE (SD). Their anti-oxidant and anti-thrombosis activities were compared. The yields of ethanol extraction in FD, HD, and SD were 14.4, 13.2 and 11.9%, respectively. The highest contents of total polyphenol (4.6 mg/g) and total sugar (23.4 mg/g) were shown in FD, whereas, the highest content of reducing sugar (14.6 mg/g) was observed in HD. In anti-oxidation activity assay, the FD and HD showed similar radical scavenging activities and reducing power. However, in SD, nitrite scavenging activity and reducing power were severely decreased. In anti-coagulation activity assay, the thrombin time (TT), prothrombin time (PT) and activated partial thromboplastin time (aPTT) of FD, HD and SD did not show significant changes at 5 mg/mL concentration. But the HD at 7 mg/mL had strong inhibitions against thrombin and blood coagulation factors. The platelet aggregation and hemolysis activities were not affected by dry methods. Our results suggest that both FD and HD are effective to maintain the functional ingredient of SE, and HD is economic and efficient dry process for production of functional food.

• Journal of Korean Society of Forest Science
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• v.108 no.4
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• pp.513-521
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• 2019

With rapid climate change and increasing global warming, the distribution of evergreen broad-leaved trees (EBLTs) is gradually expanding to the inland regions of Korea. The aim of the present study was to analyze the survival rate of 148 EBLT plantations measuring 180 ha and to determine the optimal plantation size that would help in coping with climate change in the warm, temperate climate zone of the Korean peninsula. For enhancing the reliability of our estimated survival model, we selected a set of 11 control variables that may have also influenced the survival rates of the EBLTs in the 148 plantations. The results of partial correlation analysis showed that the survival rate of 67.0±26.9 of the EBLTs in the initial plantation year was primarily correlated with plantation type by the crown closure of the upper story of the forest, wind exposure, and precipitation. For predicting the probability of survival by quantification theory, 148 plots were surveyed and analyzed with 11 environmental site factors. Survival rate was in the order of plantation type by the crown closure of upper story of the forest, wind exposure, total cumulative precipitation for two weeks prior to planting, and slope stiffness in the descending order of score range in the estimated survival model for the EBLTs with the fact that survival rate increased with shade rate of upper story to some extent.

• Current Research on Agriculture and Life Sciences
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• v.14
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• pp.85-100
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• 1996

The Studies were conducted to provide the state of mulberry cultivation and it's development in Banguet province (high land) of Philippines. Philippines initiated the sericulture industry with the technical asistance of Japan in 1974 and established mulberry field and sericultural facilities with technical asistance of Korea in 1990 and 1995. The required average of 100 to 150mm per month is not available during the dry season from December to March. Therefore mulching with grass which is available abundantly in the Philippines should be established to conserve moisture, to control soil erosion, surface ran-off and also to increase the humus content in the soil. In chemical properties of mulberry field, the pH value of soil is 4.7, organic matter 1.6%, and available phosphorus 6ppm. Therefore, all fields should do liming and be applied compost. To improve leaf yield for mulberry planted under partial shade area of pine trees, more pruning of pine tree should be done for good sunshining of mulberry, more liming and compost should be applied to improve acidic soil. To control the leaf roller, DDVP and KAFIL are able to be used. When spraying insecticides to control mulberry insect pests, care should be taken to consider the residual effects of chemicals on the leaf. Leaf should be fed to silkworms only after the leaves are free of any residual effects.