• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.10a
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• pp.55-57
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• 2005

• Journal of the Korean Electrochemical Society
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• v.6 no.4
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• pp.236-241
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• 2003

Magnetic CoW thin film alloys were electrodeposited from citrate baths to investigate the resulting microstructure and magnetic properties. Deposit tungsten (W) content in the films electrodeposited at $70^{\circ}C$ were independent of current density, while coercivity decreased from hard $(H_{c,//}\~150\;Oe\;and\;H_{c.{\bot}}\;\~240\;Oe)$ to soft magnetic properties $(H_{c,//}\~20\;Oe\;and\;H_{c.{\bot}}\;\~30\;Oe)$ with increasing current densities from $10\;to\;100mA{\cdot}cm^2$, with deposit W content $(\~40\%)$ relatively unaffected by the applied current density. X-ray diffraction analysis indicated that hcp $Co_3W$ phases [(200), (201) and (220) planes] in the CoW films electrodeposited at $70^{\circ}C\;and\;10mA{\cdot}cm^{-2}$ were dominant, whereas amorphous CoW phases with small amount of hcp $Co_3W$ [(002) planes] were dominant with deposition at $70^{\circ}C\;and\;100mA{\cdot}cm^{-2}$. At intermediate current densities $(25\;and\;50mA{\cdot}cm^{-2}),\;hop\;Co_3W$ phases [(200), (002), (201) and (220)] were observed. The average grain size was measured to be 30 nm from Sheller formula. It is suggested that the change of the deposit coercivities in the CoW thin films electrodeposited at $70^{\circ}C$ is attributed to the change of microstructures with varying the current density. Nanostructured $Co_3W/amorphous-CoW$ multilayers were fabricated by alternating current density between 10 and $100 mA{\cdot}cm^{-2}$, varying the individual layer thickness. The magnetic properties of $Co_3W/amorphous-CoW$ multilayers were strongly dependent on the thickness of the alternating hard and soft magnetic thin films. The nanostructured $Co_3W/amorphous-CoW$ multilayers exhibited a shift from low to high coercivities suggesting a strong coupling effect.

• Journal of the Korean Chemical Society
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• v.37 no.7
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• pp.655-661
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• 1993

The neutral monomeric compounds $[Mo(NO)_2Cl_2(phen)]$ and $[W(NO)_2Cl_2(phen)]$ (phen= 1,10-phenanthroline) have been prepared by reactions of polymeric compounds $[{Mo(NO)_2Cl_2}n],\;[{W(NO)_2Cl_2}n]$ with chelate ligands. Additions of one equivalent of silver(I) perchlorate to these cis-dinitrosyl compounds in acetone solution produce $[Mo(NO)_2(phen)(S)Cl][ClO_4]\;and\;[W(NO)_2(phen)(S)Cl][ClO_4]$ (S = acetone). The homo- and hetero-dinuclear complexes, $[Cl(phen)(NO)_2M(pyz)M'(NO)_2(phen)Cl][ClO_4]_2$ (M = Mo, W) and $[Cl(phen)(NO)_2M(pyz)M'(NO)_2(phen)Cl][C1O_4]_2$ (M = Mo, M' = W) have been prepared by these monocationic complexes with pyrazine ligand respectively. These complexes characterized by elemental analysis, $1^H-\;and\;^{13}C-NMR$, infrared, and UV-visible spectroscopy are reported. The spectral data indicate that homo- and hetero-dinuclear complexes were symmetrical structures of $C_{2v}$.

• Honam Mathematical Journal
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• v.33 no.1
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• pp.19-25
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• 2011

Let G be the general linear group GL(n,$\mathbb{C}$), $W_0$ the Weyl group of G and W the extended a neWeyl group of G. Then it is well-known that W is a union of the double cosets $W_{0x}W_0$ as x moves over the set of dominant weights of W. It is also known that each double coset $W_{0x}W_0$ contains a unique element $m_x$ of the shortest length. These shortest length elements belong to what are called the canonical left cells. However, it is still an open problem to find the canonical left cell containing a given $m_x$. One of the mai purposes of this paper is to introduce a new approach to attack this question. In particular, we will present a conjecture which explicitly describes the canonical left cells containing an element $m_x$. We will show that our conjecture is true for some specific types of $m_x$.

• Journal of Broadcast Engineering
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• v.15 no.1
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• pp.89-98
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• 2010

In this paper, the technical analyzing methodology has been suggested to preserve the same transmission quality of a M/W system used for FM broadcasting link after the frequency reallocation. The simulation was also performed for the actual M/W system operating in each frequency band, and its results were evaluated in terms of an availability based upon a fade margin. It was confirmed that only if the relative fade margin of more than 2.6 dB at 1700 MHz is provided, the equivalent service quality may be obtained regardless of the frequency reallocation. The suggested method will be expected to be widely used for accessing service quality of the M/W system concerned with the frequency reallocation.

• Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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• 2003.05a
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• pp.410-413
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• 2003

We have developed the measurement system for the high power laser The absorber is made of gold-plated copper cavity. The calibration heater is using a manganin(CuMn12Ni ; Isabellenhutte) coil, and output power is measured by using of resistance bridge with composed manganin and copper coil. Developed system can measure for 5∼1000w laser output power range. Calibration factors are 489.13 J/mV at 100W range and 489.13 J/mV at 500W range. Correction factors are 0.99 at 100W range and 1.006 at 500W range.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.3
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• pp.211-218
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• 1982

The specific heat capacity and density of soybean oil and soy protein composing of the soybean curd were measured between $30^{\circ}C\;and\;-40^{\circ}C$. The thermal conductivity of soybean oil was measured to be 0.160 and 0.140, $W/m{\cdot}K$ at unfrozen and frozen states, respectively. The effective thermal conductivity of the soybean curd depended not only on its water content but also on its fat and protein contents.

• Economic and Environmental Geology
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• v.42 no.6
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• pp.591-598
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• 2009

We made 2511 thermal property measurements on igneous, metamorphic, and sedimentary rock samples from Korea. The average thermal conductivities of igneous, metamorphic, and sedimentary rocks are 3.10 W/m-K, 3.76 W/m-K, and 3.54 W/m-K, respectively. Igneous rock can be classified into pluton, hypabyssal rock, and volconic rock; the average thermal conductivities of those rock types are 3.16 W/m-K, 3.26 W/m-K, and 2.77 W/m-K, respectively. Nonclastic sedimentary rock has higher thermal conductivity than clastic sedimentary rock. Thermal conductivity of Palezoic era rock is higher than Mesozoic era rock, because dominant mineral contents play an important role in the determination of thermal conductivity. Thermal conductivity of rocks is influenced by porosity. Therefore thermal conductivity of sedimentary rocks generally decreases with increasing porosity. Thermal conductivity and thermal diffusivity show linear correlation, its correlation coefficient of igneous, metamorphic, and sedimentary rocks are 0.775, 0.855, and 0.876, respectively.

• Journal of the Korean Society of Hazard Mitigation
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• v.10 no.5
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• pp.75-82
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• 2010

To study the combustion characteristics of forest fuel by fire intensity, the experiment of combustion characteristics on Pinus Densiflora living leaves, which is the weakest species to the forest fire, was delivered, using variables of heat flux(25 kW/$m^2$, 50 kW/$m^2$, 75 kW/$m^2$). With the equipment of Cone calorimeter, the characteristics of ignition, heat, smoke release, CO and $CO_2$ release, and mass loss were analyzed. Pinus Densiflora living leaves containing moisture of 60.66% were not ignited at the heat flux of variables 25 kW/$m^2$, 50 kW/$m^2$, 75 kW/$m^2$. In proportion to the heat flux value, heat release amount and heat release rate reached maximum value rapidly: higher variables came to the maximum by the half rapidity and the maximum value were twice higher than the former lower variables respectively. As for the smoke release, the less heat flux the variable had, the more smoke release it had, due to incomplete combustion. The release amount of CO and $CO_2$ had more maximum value as the heat flux increased and more radiant heat meaned more carbon oxide. When the forest fire breaks out, therefore, a great amount of CO and $CO_2$ will be released by Pinus Densiflora.

• Korean Journal of Food Science and Technology
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• v.27 no.6
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• pp.834-838
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• 1995

The relative retrogradation of Jeungpyun investigated with different milling methods of rice flour. The relative retrogradation of Jeungpyun was reduced in order that of W-C, W-P, D-M, D-J in DSC(Differential Scanning Calorimetry) method while W-C, D-M, D-J, W-P in Diastase method. In wet milling method, the relative retrogradation of Jeungpyun by pin mill (W-P) was lower than Jeungpyun by colloid mill (W-C). In dry milling method, the relative retrogration of Jeungpyun by jet mill (D-J) was lower than Jeungpyun by micro mill(D-M). The relative retrogradation of Jeungpyun by DSC method was similar to the diastase method. The relative retrogradation of Jeungpyun was decreased with decreasing particle size and setback value for amylogram and increasing damaged starch.