• Journal of the Korean Mathematical Society
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• v.55 no.3
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• pp.671-694
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• 2018

In this paper, we investigate the weighted vector-valued bounds for a class of multilinear singular integral operators, and its commutators, from $L^{p_1}(l^{q_1};\;{\mathbb{R}}^n,\;w_1){\times}{\cdots}{\times}L^{p_m}(l^{q_m};\;{\mathbb{R}}^n,\;w_m)$ to $L^p(l^q;\;{\mathbb{R}}^n,\;{\nu}_{\vec{w}})$, with $p_1,{\cdots},p_m$, $q_1,{\cdots},q_m{\in}(1,\;{\infty})$, $1/p=1/p_1+{\cdots}+1/p_m$, $1/q=1/q_1+{\cdots}+1/q_m$ and ${\vec{w}}=(w_1,{\cdots},w_m)$ a multiple $A_{\vec{P}}$ weights. Our argument also leads to the weighted weak type endpoint estimates for the commutators. As applications, we obtain some new weighted estimates for the $Calder{\acute{o}}n$ commutator.

• Journal of the Korean Mathematical Society
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• v.47 no.4
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• pp.789-804
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• 2010

We here investigate an existence and uniqueness of the nontrivial, nonnegative solution of a nonlinear ordinary differential equation: $$[\mid(w^m)]'\mid^{p-2}(w^m)']'\;+\;{\beta}rw'\;+\;{\alpha}w\;+\;(w^q)'\;=\;0$$ satisfying a specific decay rate: $lim_{r\rightarrow\infty}\;r^{\alpha/\beta}w(r)$ = 0 with $\alpha$ := (p - 1)/[pd-(m+1)(p-1)] and $\beta$:= [q-m(p-1)]/[pd-(m+1)(p-1)]. Here m(p-1) > 1 and m(p - 1) < q < (m+1)(p-1). Such a solution arises naturally when we study a very singular solution for a doubly degenerate equation with nonlinear convection: $$u_t\;=\;[\mid(u^m)_x\mid^{p-2}(u^m)_x]_x\;+\;(u^q)x$$ defined on the half line.

• Bulletin of the Korean Mathematical Society
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• v.56 no.5
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• pp.1187-1198
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• 2019

Let R be a domain with its field Q of quotients. An R-module M is said to be weak w-projective if $Ext^1_R(M,N)=0$ for all $N{\in}{\mathcal{P}}^{\dagger}_w$, where ${\mathcal{P}}^{\dagger}_w$ denotes the class of GV-torsionfree R-modules N with the property that $Ext^k_R(M,N)=0$ for all w-projective R-modules M and for all integers $k{\geq}1$. In this paper, we define a domain R to be w-Matlis if the weak w-projective dimension of the R-module Q is ${\leq}1$. To characterize w-Matlis domains, we introduce the concept of w-Matlis cotorsion modules and study some basic properties of w-Matlis modules. Using these concepts, we show that R is a w-Matlis domain if and only if $Ext^k_R(Q,D)=0$ for any ${\mathcal{P}}^{\dagger}_w$-divisible R-module D and any integer $k{\geq}1$, if and only if every ${\mathcal{P}}^{\dagger}_w$-divisible module is w-Matlis cotorsion, if and only if w.w-pdRQ/$R{\leq}1$.

• Journal of Technologic Dentistry
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• v.18 no.1
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• pp.67-72
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• 1996

This test is verifying for influence of W/P ratio of investment upon dental prosthesis Firstly we made 40 MOD die and divide 4 groups, each group take 0.2 different w/p ratio grade such as 0.35, 0.37, 0.39 and 0.41. The method of data analysis applied were by ANOVA, Tukey test and Mann-Whiney and Kruskal Wallis test. The finding of this study were as follows : 1. The 0.37 w/p ratio group showed most accurte margin due to $15.8{\mu}m$ gap between margin and die which keep up with manufacture's instruction and 0.35 w/p ratio group was followed as second accuracy group o 새 $48.3{\mu}m$ gap between margin and die, 0.39 w/p ratio group showed $101{\mu}m$ gap and 0.41 w/p ratio group showed $129.8{\mu}m$ gap. 2. As to the relationship of the margin accuracy between 4 different grade of w/p ratio groups, each group was statistically significant(P<0.01). Also the all groups were statistically significant except between 0.35 and 0.37 groups between 0.39 and 0.41 groups, and between 0.35 and 0.39 groups. 3. A consequence of Mann-Whitney & Kruskal-Wallis test for marginal accuracy between 4 different grade of w/p ratio was statistically significant as same as above ANOVA test result. Also Tukey test for verifying similarity from each group showed same as above.

• Bulletin of the Korean Chemical Society
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• v.15 no.5
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• pp.379-386
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• 1994

Reactions of 1',2-bis(diphenylphosphino)-l-(N,N-dimethylaminomethyl)ferrocene (FcNPP) with $M(CO)_6$ (M=Cr, Mo, W) in the presence of TMNO (Trimethylamine oxide) in a stoichiometric ratio of 1 : 1.5 : 3.5 produced a series of Gp 6 metal carbonyl derivatives with a variety of coordination modes: M(CO)$_4({\eta}^2$-FcNPP-P,P) (M=Cr, Mo, W), $M(CO)_5({\eta}^1-FcNPP-P) (M=Mo, W)\;,\; M_2(CO)_9({\eta}^1\;,\;{\eta}^2-FcNPP-P,P,N) (M=Cr, Mo)\;,\;M_2(CO)_{10}({\eta}^1\;,\;{\eta}^1-FcNPP-P,P) (M=Cr, Mo, W)\;, and\;W(CO)_4({\eta}^2-FcNPP(O)-P,N)$. All these complexes were characterized by microanalytical and spectroscopic techniques. In one case, the structure of W(CO)$_4({\eta}^2$-FcNPP(O)-P,N) was determined by X-ray crystallography. Crystals are monocinic, space group P$2_{1/C}$, with a=10.147(2), b=19.902(3), c=19.821(4) ${\AA},\;{\beta}=96.88(2)^{\circ},\;V=3974(l){\AA}^3$, Z=4, and $D_{calc}=1.64 g cm^{-3}$. The geometry around the central tungsten metal is a distorted octahedron, with the nitrogen and phosphorus atoms being cis to each other. Some of these complexes exhibited catalytic activities in the allylic oxidation and epoxidation of cholesterly acetate. Other oxidation products were also formed with the different chemical yields and product distribution depending upon the ligand and the central metal.

• Journal of the Korean Electrochemical Society
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• v.9 no.4
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• pp.141-150
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• 2006

Nanocrystalline CoW thin/thick film alloys were electodeposited from citrate baths to investigate the influences of metal ion concentration, current density and solution pH on chemical composition, current efficiency, residual stress, surface morphology, and microstructure of the film. Deposit W (tungsten) content in CoW thin/thick film increased with increasing W ion concentration, current density, and solution pH in the plating bath. It was observed that residual stress in CoW thin/thick film decreased with increasing W ion concentration and solution pH. CoW thin film exhibited mixed phases of hop Co [(100) and (002)] and hcp $Co_3W$ [(002) and (201)] at W ion concentration with 0.02 to 0.08 M. The microstructure of CoW thin film at W ion concentration of 0.1 to 0.2 M was close to amorphous phase. The dominant phases were found to be hop Co (002) and hop $Co_3W$ [(200), (002) and (201)] at the current densities of 5, 10, 25, and $100mA{\cdot}cm^{-2}$ CoW thin film at the current densities of 50 and $75mA{\cdot}cm^{-2}$ was close to amorphous phase. At solution pH 8.7, CoW thin film exhibited hcp Co (002) and hop $Co_3W$ [(200), (002) and (201)]. Below solution pH 8.7, CoW thin film exhibited amorphous microstructure. The optimum electrodeposition conditions for CoW thin/thick film were found to be W ion concentration of 0.08 M, current density of $10mA{\cdot}cm^{-2}$, and solution pH 8.7.

• 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.

• Journal of the Korean Chemical Society
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• v.17 no.6
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• pp.428-433
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• 1973

The quantitative separations of a mixture containing equal amount of each anion such as Si(IV), As(V), P(V), S(VI), W(VI) and Cr(VI) are carried out by the elution through 20${\times}3.14cm^2$ column of anion exchange resin, Dowex 1${\times}$8. The eluents are a mixture of 0.07 M hydrochloric acid and 0.03 M sodium chloride (pH = 1.30) for Si(IV), As(V) and P(V) species, a mixture of 0.6 M sodium chloride and 0.3 M sodium hydroxide for S(VI), W(VI) and Cr(VI) species, and 0.1 N sodium sulfite (pH = 3.48) for P(V) and As(V) species. The subsidiary anions in a standard mixture such as Si(IV), As(V), S(VI), P(V) and W(VI) are separated together from large amount of Fe(III) by the elution through 30cm${\times}3.14cm^2$ column of the resin, Dowex${\times}$50w${\times}$12, using a mixture of 0.1 M sodium nitrate and 2 percent dimethylsulfoxide aqueous solution as an eluent. Si(IV), As(V), S(VI), P(V) and W(VI) eluted together are separated quantitatively under the same conditions as in the separations of the anion mixture. By the conditions obtained in the separations of the standard mixture, Fe(III) and all of the subsidiary anions in steel are quantitatively separated.

• 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.

• Journal of Nutrition and Health
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• v.24 no.5
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• pp.399-407
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• 1991

The purpose of this study was to estimate the intake of individual fatty acid and eventually to contribute to the establishment of dietary guidelines and recommendations of fatty acids for the Koreans. The subjects consisted of female college students aged 20 to 29 years old. Their dietary intake was assessed twice. in summer and in winter, by means of a 24-hour dietary recall method. Food models and other measuring tools were also used. Concentrations of serm total triglyceride, total cholesterol and HDL-& LDL-cholesterol were measured. The subjects consumed 12.3g of polyunsaturated fatty acids, 14.3g of monounsaturated fatty acids and 14.99g of saturated fatty acids per day The ratios of polyunsaturated/saturated fatty acids( P/S) and polyunsaturatedimonounsaturatedi saturated fatty acids (P/M/S) taken by the subjects were 0.8/1.0 and 0.8/l.0/l.0, respectively. The ratio of w61w3 fatty acids was found to be 8.3/l.0. All of these values seem to fall in the desirable range. The percentages of total calorie from carbohydrate. fat and protein were 59.4%, 23.4% and 17.2%, respectively. The concentrations of serum total triglyceride, total cholesterol. HDL-cholesterol and LDL-cholesterol were 59.3ms/dl, 192.7mg/dl, and 59.0mg/dl, and 121.9mg/dl., respectively.