• Korean Journal of Food Science and Technology
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• v.9 no.2
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• pp.138-143
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• 1977

Physicochemical properties of buckwheat starch were investigated. Starch granules were in the range of $4.3{\sim}11.4$ microns in size, the average being 7.8 microns. The starch had a water-binding capacity value of 103.7%, blue value of 0.35 and amylose content of 25%. The initial and final gelatinization temperatures were $61^{\circ}$ and $65^{\circ}C$, respectively. Amylograph data showed that the starch had an initial pasting temperature of $64.5^{\circ}C$. The kinetic study of crystallization of buckwheat starch during aging at $21^{\circ}C$ suggested that the mechanism of starch crystallization is instantaneous nucleation followed by rod-like growth of crystals.

• The Transactions of The Korean Institute of Electrical Engineers
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• v.66 no.9
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• pp.1317-1324
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• 2017

These days, a penetration of distributed generation(DG) has increased in power system. Due to increased penetration of DG, a whole system is forced to install the maximum hosting capacity of DG. Therefore analysis between the maximum hosting capacity of DG at the target bus and the whole system is important. If we know the maximum hosting capacity, it will be able to satisfy the demand of system planner and customer. In this paper, we use a genetic algorithm to calculate the hosting capacity with optimization program using Design Analysis Kit for Optimization and Terascale Applications(DAKOTA). To consider a real system, we establish constraints and use IEEE 34 node test system. In addition, through the correlation coefficient between the target bus and the other buses, when capacity of DG at the target bus increases, we analyze which capacity of DG at the other buses will be decreased.

• Resources Recycling
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• v.10 no.1
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• pp.49-55
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• 2001

The strategy of recovering metals from scrap is in general much different from primary sources. One of the main differences between the treatment of scrap and that of primary sources lies with the fact that metals are frequently associated with other met-als to form alloys in scrap, while metals occur in primary sources as oxides or sulfides. In this paper, factors affecting the dis-solution behavior of metals from various alloy systems have been reviewed and discussed. Specific examples have been drawn from Au/Ag, Au/cu and Ag/cu systems. Results of the dissolution behavior of various metals from these alloys have been reviewed and compared to the dissolution behavior of single metal systems in various lixiviants such as acids, cyanide and ammonia. It has been observed that the presence of other metals in alloys would significantly affect the dissolution rate of the metal in question. The leaching behavior of metals from homogeneous alloys relies on the chemical interaction between atoms in the lattice of the alloys, while that from heterogeneous alloys is affected by galvanic interaction established in the solution The manner in which the dissolution of a certain metal is influenced by surrounding metals has been discussed in terms of pas-sive and noble nature of the metal in relation to the neighboring metals. The role of the standard electrochemical Potential of these metals on the selective dissolution for a given lixiviant has also been discussed.

• Journal of the Mineralogical Society of Korea
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• v.9 no.1
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• pp.7-16
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• 1996

Partially sericitized tourmaline from a pegmatite, Black Hills, South Dakota, U.S.A., was investigated using high-resolution transmission electron microscopy (HRTEM). Muscovite occurs as the only alteration product of tourmaline, and it is developed extensively as narrow veinlets along the {110} and {100} cleavage directions of tourmaline, indicating that a cleavage-controlled alteration mechanism was dominant. Muscovite was characterized mainly as two-layer polytypes with minor stacking disorder, but tourmaline is almost free of structural defects. HRTEM images of tourmaline-muscovite interfaces revealed that the interfaces between two minerals are composed of well-defined {110} and {100} boundaries of tourmaline. The (001) of muscovite is in general parallel to the c-axis of tourmaline, but tourmaline and replacing muscovite do not show specific crystallographic orientation relationship; muscovite consists of numerous 100-1000$\AA$ thick subparallel packets, and the angles between the (001) of muscovite and (110) of tourmaline is highly variable. Al/Si ratios of both minerals suggest that tourmaline to muscovite alteration by late magnetic fluids has been facilitated by their similar Al/Si ratio in the incipient alteration stage, in that the hydration reaction with preservation of Al and Si would require only addition of K+ and H2O. Aluminous minerals other than muscovite were not characterized as the alteration products of tourmaline, indicating that tourmaline reacted directly to muscovite; the tourmaline alteration apparently occurred by the presence of residual fluids in which K+ is available and silica was not undersaturated.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.3-8
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• 2001

The mineral industry of the United States is going through a challenging time. The US as an industrial nation faces with increasing demand in raw materials to fuel various industrial sectors but, at the same time, meeting environmental constraints associated with excavating and extracting these raw materials. In addition, gradual depletion of material resources. and the necessity of handling more complex forms of resources of primary origin have led to a decline in her resource productivity, once a strategic advantage of the U.S. As a result. the United States currently relies heavily upon foreign importation of various materials such as precious and strategic metals. However, since the US is the major consumer of most of these materials, the recovery of these values from scrap would help renew her position as a resource-producing nation, and ultimately help spur its domestic economy. Furthermore. recycling would also help maintain a clean environment and reduce energy consumption. In this paper. the author attempts to discuss opportunities and challenges lied ahead of the US mineral in relation to recovering their much-needed resources from secondary sources. The need and demand in various metals in the US will be reviewed and discussed. The implication of resource recovery from secondary sources will also be discussed. Extraction methods treating secondary sources are inherently different from those for primary sources. There is a need for new technologies which are metallurgically efficient and environmentally benign in treating secondary sources. Ways to meet such a need will be examined and key factors to be considered in approaching these challenges will be discussed.

• Archives of Pharmacal Research
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• v.26 no.11
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• pp.912-916
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• 2003

Four known lanostane triterpenoids, schiprolactone A (1), schisanlactone B (2), nigranoic acid (3) and schisandronic acid (4) Were isolated from the stems of Schisandra henryi for the first time. Their structures were characterized by IR, MS and NMR techniques. Compounds 1, 2 and 4 showed moderate cytotoxic activity against Leukemia cells in vitro. Cytotoxic activity of compounds 1-4 showed $IC_{50}$ of 0.0097, 0.01, 0.097 and 0.0099 $\mu$ mol/mL respectively toward Leukemia cells and $IC_{50}$ of 0.097, 0.1, 0.097 and 0.099 $\mu$mol/mL toward Hela cells respectively. It is the first report that these compounds possess cytotoxic activity on Leukemia and Hela cells.

• Journal of Sensor Science and Technology
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• v.20 no.6
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• pp.375-381
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• 2011

Ionic polymer-metal composite(IPMC) consists of an ion conductive membrane plated by metallic electrodes on both surfaces. When it bends, a voltage is generated between two electrodes. Since IPMC is flexible and thin, it can be easily mounted on the various surfaces of a body. The present study investigates a sensor system using IPMC to effectively detect the bending angles applied on IPMC sensor. The paper evaluates several R and C circuit models that describe the physical composition of IPMC and selects the best model for the detection of angles. The circuit models implemented with a charge model describe the relationship between input bending angles and output voltages. The identification of R and C values was performed by minimizing the error between the real output voltages and the simulated output voltages from the circuit models of IPMC sensor. Then the output signal of a sensor was fed into the inverse model of the identified model to reproduce the bending angles. In order to support the validation of the model, the output voltages from an arbitrary bending motion were also applied to the selected inverse model, which successfully reproduced the arbitrary bending motion.

• Child Health Nursing Research
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• v.12 no.2
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• pp.189-195
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• 2006

Purpose: The purpose of this study was to examine the effect of a maternal self-efficacy promotion program for Korean primiparas on maternal confidence and mother-infant interaction. Method: This study was non-equivalent quasi-experimental research with a control group selected by purposive sampling. Based on Bandura’s (1986) self-efficacy theory, the research team developed the maternal self-efficacy promotion program. The program included achievement experiences, verbal persuasion, and vicarious experiences. The program was provided through face-to-face teaching at the time of discharge, counseling sessions over the telephone, and a home visit. Subjects also learned about parenting skills using a videotape developed by the research team. Sixteen primiparas were recruited to the experimental group at one hospital in Kyongi province, and fifteen primiparas who were matched according to socioeconomic status were recruited to the control group at a postpartum care center in the same province. Results: Subjects in the experimental group demonstrated significantly higher maternal confidence and mother-infant interaction than those in the control group. Conclusion: The maternal self-efficacy promotion program appears to be an effective nursing intervention for parenting of first-time mothers in Korea.

• Asian-Australasian Journal of Animal Sciences
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• v.11 no.6
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• pp.755-768
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• 1998

Nitrogen and phosphorus are major nutrients in animal feeds which partially remain in the environment as pollution. In addition, nitrogen and phosphorus along with energy are the main nutrients which determine the feed cost. Any decreases in the levels of these three nutrients can contribute to reducing the pollution problem as well as the cost of feed. The nutrient requirements for chickens in the work here reported should allow for the addition of mixed enzymes (phytases, proteases, glucanases, xylanases and others). Such minimal levels of crude protein in the research results which are here reported are 16% for 0-6 weeks of age, 13.5% for 7-12 weeks of age, 11.5% for 13-18 weeks of age for layer type chicks, 13% for layer, 18% for 0-3 weeks of age broiler and 16.5% for 4-7 weeks of age broiler. These research projects have been done without adding enzyme supplements to their experimental diets. The minimal values of phosphorus, shown as available phosphorus, are 0.25% for pullets, 0.09% for layers and 0.25% for broilers with the addition of phytase. The minimum energy requirement (metabolizable energy) for reducing the feed cost could be summarized as 2,750 kcal per kg feed for pullets, 2,800 kcal for layers and 2,700 kcal for broilers.

• Korean Journal of Organic Agriculture
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• v.12 no.2
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• pp.135-151
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• 2004

U.S. organic farming has grown rapidly-20 percent or more annually-throughout the 1990s, which kept pace with consumer demand for organically produced food. Thus certified organic acreage is the total to 235 million acres in 48 state in 2001, and SO the U.S. ranked fourth in land area managed under organic farming systems. And according to several surveys, consumer's reasons for purchasing organic food are health and nutrition, taste and environmental concerns. California and North Dakota were the top two states in 2001 for certified organic cropland; the former with mostly fruits and vegetables, and the latter with wheat, soybeans, and other crops. And the top two states for certified organic pasture were Colorado and Texas. And then several states such as Iowa and Minnesota have begun subsidizing conversion to organic farming systems as a way to capture the environmental benefits of these systems. The price of organic produce fluctuates rather broadly because of being traded by market economy principle and of demand-supply disequilibrium. Nevertheless, average price premiums for organic produce are higher than the prices for the produce under conventional farming. Future prospects for U.S. organic farming are as follows; Demand for organically grown foods is expected to continue growing at a rapid pace, as more growers convert to organic production and more processors and distributors expand organic selections in their product lines. And new processed products and new types of healthy foods are likely to appear on the market, and some new organic products will be aimed at mainstream markets.