• Journal of Radiation Protection and Research
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• v.13 no.2
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• pp.1-8
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• 1988

The energy losses of ${\alpha}$-particle with 3 to 5.4 MeV energy were measured as a function of gas absorber thickness and ${\alpha}$-particle energy in three light gaseous media; He, Ar, and $N_2$. The stopping powers and stopping cross-sections were determined by analyzing these data. For Ar gas, the experimental values are very well consistent with the corresponding values of Srivastava's stopping-power theory with the condition of the completely and partially stripped ion. For $N_2$ and He gases, these experimental values express the inconsistencies of about $13{\sim}36%$ and $27{\sim}28%$, respectively.

• Korean Journal of Soil Science and Fertilizer
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• v.20 no.1
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• pp.55-61
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• 1987

A series of laboratory experiments were carried out to find the effects of soil organic matter contents, soil temperature, pH values, kinds and amount of nitrogen fertilizers on the denitrification-$N_2O$ gas evolution-. The results obtained were summarized as follows: 1. Denitrification rate, amount of $N_2O$ gas evolution, was influenced the order of organic matter contents>soil temperature>pH values>kinds of N-fertilizer>levels of N-fertilizer. 2. The highest dentrification rate was observed in organic matter content of 3.0%, pH values at 6.0 with application of $KNO_3$ at levels of 20 mgN/100g soil. 3. For the evolution of I mole $N_2O$ gas, averaged carbon consumption was obtained as 0.5 mole in all these experiment condition. However, the highest carbon consumption rate was obtained in organic matter contents for 1.0% with application of $(NH_4)_2SO_4$ at levels of 10 mgN/100g soil (1.06 mole) while lowest carbon consumption rate was obtained in organic matter contents for 3.0% with application of $KNO_3$ at levels of 20 mgN/100g soil (0.13 mole). 4. According to Michaelis-Menten's equation, the V/2 values for evolution of $N_2O$ gas was estimated by progress curve. The results obtained was as 550 ug for $(NH_2)_2CO$ and 1100 ug $N_2O/100g$ soil by application of $KNO_3$ in organic matter contents of 1.0% soil. On the other hand, when the application $(NH_4)_2SO_4$ the V/2 values of $N_2O$ gas was obtained as the amount of 490 ug/100g soil while V/2 values of $N_2O$ gas by application of $KNO_3$ was on the linear line in soil organic matter contents of 3.0%.

• Bulletin of the Korean Chemical Society
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• v.34 no.9
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• pp.2697-2701
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• 2013

The solvolysis rate constants of piperonyloyl chloride (1) in 27 different solvents are well correlated with the extended Grunwald-Winstein equation, using the $N_T$ solvent nucleophilicity scale, $Y_{Cl}$ solvent ionizing scale, and I aromatic ring parameter with sensitivity values of $0.30{\pm}0.05$, $0.71{\pm}0.02$, and $0.60{\pm}0.04$ for l, m, and h, respectively. The solvent kinetic isotope effect values (SKIE, $k_{MeOH}/k_{MeOD}$ and $k_{50%MeOD-50%D2O}$) of 1.16 and 1.12 were also in accord with the values for the $S_N1$ mechanism and/or the dissociative $S_N2$ mechanism. The product selectivity values (S) for solvolysis of 1 in alcohol/water mixtures were in the range of 0.5 to 1.9, which is also consistent with the proposed unimolecular ionization mechanism.

• Journal of the Korean Data and Information Science Society
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• v.21 no.4
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• pp.803-811
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• 2010

This study analyzes the characteristics of preference ratings by dividing estimated values into four groups according to rank correlation coefficient after obtaining preference estimated value to user's ratings by using collaborative filtering algorithm. It is known that the value of standard error of skewness and standard error of kurtosis lower in the group of higher rank correlation coefficient This explains that the preference of higher rank correlation coefficient has lower extreme values and the differences of preference rating values. In addition, top n recommendation lists are made after obtaining rank fitting by using the result ranks of prediction value and the ranks of real rated values, and this top n is applied to the four groups. The value of top n recommendation is calculated higher in the group of higher rank correlation coefficient, and the recommendation accuracy in the group of higher rank correlation coefficient is higher than that in the group of lower rank correlation coefficient Thus, when using standard error of skewness and standard error of kurtosis in recommender system, rank correlation coefficient can be higher, and so the accuracy of recommendation prediction can be increased.

• Asian-Australasian Journal of Animal Sciences
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• v.12 no.2
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• pp.189-191
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• 1999

Mineral profile of serum and cerebrospinal fluid (CSF) of 15 Himalayan Yak (adult female, n=8; adult male n=4 and young male,n=3) was studied in their natural habitat at an altitude of 3300 meters above mean sea level at Sangla in north western Himalayas. The macro and micro minerals estimated in serum and CSF were; Sodium, Potassium, Calcium and Magnesium and Zinc, Copper and Iron respectively. The values recorded among different Yak groups did not significantly differ from each other except serum iron and haemoglobin which were significantly higher (p<0.05 ) in young male Yaks compared to the adult male and female Yaks. An observation of great significance was considerably higher potassium and lower sodium level in Yaks compared to other bovine species of plains. The serum potassium values in some adult female Yaks were recorded as high as 10.4 mEq/l and the values varied between 6.6 to 9.8 mEq/l in young male Yaks. The serum Sodium values and Na:K ratios in Yak serum ranged between 117.5 to 122.6 mEq/l and 13.7 to 15.3 respectively. The possible relationship of high serum Potassium value with hypoxic conditions and hostile mountain environment has been discussed.

• Proceedings of the KSR Conference
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• 2001.05a
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• pp.451-458
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• 2001

The purpose of this study was to evaluate shear parameters on cutting slope of weathered granite soils by using small dynamic cone penetration test on the very moment of its cutting. The results were : On the relations among N$\_$c/, Li, and CEC, the condition of Li＞6%, CEC＞14(meq/100g) corresponds to that of N$\_$c/ values of 2∼30, and 3＜CEC＜14(meq/100g) to N$\_$c/=30∼50. Comparing the smallest penetration depth from two small dynamic cone penetration tests done at 5m below from the top of the slope on April 15th, October 31t. there was a l0cm difference. So we could find out the degree of weathering on the slope. And dividing the difference by 190 days (the whole testing time), we could know it's being weathered 0.052mm each day. The more N. value increases, the more shear parameters(internal friction angle ; $\phi$, cohesion : c) increase at a standard pressure($\sigma$＞32㎪). So the condition of N$\_$c/=2∼50 corresponds to that of $\phi$=27∼50, c=12∼49㎪. From the above testing results, the N$\_$c/ values more correspond to $\phi$ values than c values. In conclusion, this study suggests that on small dynamic cone penetration test a penetration boundary line of 5 centimeters is decided at around Li=4%, CEC=3(meq/100g) which is classified as a strong weathering soil. It also shows that as Li increases CEC increases as well, while N$\_$c/ decreases.

• Korean Journal of Soil Science and Fertilizer
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• v.42 no.1
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• pp.14-20
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• 2009

Classification of land uses and analysis of nitrogen isotope fractionation in groundwater nitrate were carried out to examine its contamination sources in Jeju province. ${\delta}^{15}N$ values of urea (hydrolyzed with urease), ammonium sulfate, compost, water from septic tank were -1.7, -5.8, +14.1, and +24.0‰, respectively. Urea, when it was directly distillated, showed -16.5‰. Based on these ${\delta}^{15}N$ values, sources of nitrate could be classified as originated from chemical fertilizers with ${\delta}^{15}N$ values below +5‰ and as from animal manure or municipal waste with ${\delta}^{15}N$ values over +10‰. Results of ${\delta}^{15}N$ analysis of 33 wells showed that most wells had the chemical fertilizers as their dominant contamination source. However, some wells were contaminated by other sources: animal wastes or municipal wastes. Some wells were also contaminated by the combined sources of nitrate. It was also demonstrated that ${\delta}^{15}N$ analysis could be a useful tool even in the case where no apparent contamination source is found.

• Bulletin of the Korean Chemical Society
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• v.18 no.5
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• pp.488-495
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• 1997

The stability of bridgehead olefins containing 8 and 10 membered rings has been investigated by the MMX molecular mechanics calculation together with the GMMX conformational searching program. A number of 'hyperstable' bridgehead olefins, which have negative olefin strain values, have been found from the calculated values of strain energy and olefin strain for the series of in- and out-bicyclo[n.3.3]alk-1-ene and in- and out-bicyclo[n.4.4]alk-1-ene (n=1 to 8). For the bridgehead olefins with 'out' topology, hyperstable olefins were found in the systems having cyclononene or larger rings. For the bridgehead olefins with 'in' topology, hyperstable olefins were found in the systems having cyclodecene or larger rings.

• Proceedings of the Korean Society of Agricultural Engineers Conference
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• 2000.10a
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• pp.513-518
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• 2000

It has been acknowledged that fertilizer, natural soil nitrogen and animal waste, municipal waste have different mass ratio of nitrogen which is presented as a symbol of $\delta^{15}$N. and that the values of $\delta^{15}$N for fertilizer and natural soil nitrogen and animal waste are placed less than +5$\textperthousand$ and higher than +10$\textperthousand$, respectively. thus, Nitrogen pollution sources and contribution can be interpreted in watershed through $\delta^{15}$N analysis and then, analysis is performed with Kjeldhl-Dumas method. In this study, The values of $\delta^{15}$N are between +1.46$\textperthousand$ and +8.97$\textperthousand$, and the nitrate concentration is placed less than 3.31mg/L and higher than 0.19mg/L, respectively. Thus, this watershed is noncontamination area at the present time. But as a result of $\delta^{15}$N, contribution of natural soil nitrogen be discovered in this watershed, presently.

• Journal of applied mathematics & informatics
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• v.23 no.1_2
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• pp.471-477
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• 2007

In this paper we establish some recurrence relations satisfied by the quotient moments of the upper record values from the Weibull distribution. Suppose $X{\in}WEI({\lambda})\;then\;E(\frac {X^\tau_U(m)} {X^{s+1}_{U(n)}})=\frac{1}{(s-\lambda+1)}E(\frac {X^\tau_U(m)}{X^{s-\lambda+1}_{U(n-1)}})-\frac{1}{(s-\lambda+1)}+E(\frac{X^\tau_U(m)}{X^{s-\lambda+1}_{U(n)}})\;and\;E(\frac {X^{\tau+1}_{U(m)}}{X^s_{U(n)}})=\frac{1}{(r+\lambda+1)}E(\frac{X^{\tau+\lambda+1}_{U(m)}}{X^s_{U(n-1)}})-\frac{1}{(\tau+\lambda+1)}E(\frac{X^{\tau+\lambda+1}_{U(m-1)}}{X^s_{U(n-1)}})$.