• The Korean Journal of Mycology
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• v.3 no.1
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• pp.1-19
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• 1975

Since the importance of casing in fruit body formation of Agaricus bisporus has been emphasized, physico-chemical characteristics of casing materials were discussed by many workers and a mixture of peat and mineral soil as proper casing material has been adopted in many of mushroom growing countries. Because of limited resources of peat in Korea, it is necessary to find practical performance and substitutional materials for casing. The effect of casing on mycelial growth and mushroom yield of A. bisporus varied with materials, its combination and practices etc. The experiments to be discussed in this paper are concerned with pH and Ca of casing material which influence A bisporus, and changes of physico-chemical characteristics with mixing ratio of casing materials and its effect on A. bisporus. The optimum range of moisture content of each material, management of watering and application of physico-chemical characteristics casing materials was also investigated and re-use of weathered spent compost for casing material was described. 1. The effect of calcium on mycelial growth of A. bisporus at various pH in Halbschalentest showed different results with calcium sources. Best results were obtained around neutrality and fresh weight of fruit bodies grown in the range of pH 7 to 8 was highest among the tested levels. 2. Available moisture, pore space, organic matter, cation exchangeable capacity and exchangeable cation was increased by an increase of mixing ratio of peat in casing materials, while an adverse effect was obtained by addition of sand. 3. Mycelial growth on clay loam was more rapid at a lower bulk density of 0.75g/cc and at 20% moisture content on a dry weight basis at the same bulk density. 4. Mixing ratio of casing materials, 60 to 80 per cent by volume of peat mixed with 20 to 40 per cent of clay loam produced the highest yield of fresh fruit bodies and sand the lowest. However, per cent of open cap was highest in peat and lowest in sand. 5. Days required for fruit body initiation was shortened in mixtures of peat and clay loam by one to three days compared with other materials and the formation of flushes was clear. 6. The effect of some physico-chemical characteristics of casing materials on the fresh weight of fruit bodies were estimated by a multiple regression equation; Y=-923.86+$8.18X_1+8.04X_2+7.90X_3+0.12X_4+2.03X_5-0.82X_6-0.54X_7$ where $X_1,X_2,X_3,X_4,X_5,X_6,X_7$ are sand, silt, clay, available moistuer, porosity, organic matter and exchangeable cation respectively. The productivity of certain casing material could be predicted from this equation. 7. Fresh weight of fruit bodies was positively correlated with porosity exchangeable cation, organic matter, available moisture, silt and clay of materials; while sand was negatively correlated. On the contrary, sand was the unique factor reducing per cent of open cap. 8. Distribution of three phases of high productive casing material was concentrated in the range of 10 to 30 per cent solids, 15 to 30 per cent liquids, and 50 to 60 per cent in air volume. 9. Fresh weight of fruit bodies from peat was not affected with heavy watering but in clay loam and sandy loam severe crop losses occurred. Fresh weight of individual fruit was increased and open caps were decreased with heavy watering but light watering resulted in adverse effects: its effect was especially great in peat. 10. Optimum range of moisture content by weight on a dry basis was different with each casing material. To maintain optimum moisture content concerned with yield of fruit bodies and open cap, sandy loam and peat mixtures required daily watering of 0.6, 0.6 to 1. 2 and 1.2 to 2.4 liters per $3.3m^2$ of bed area, respectively. 11. Maximum yield of fruit body was recorded in the range of pF 2. 0 to 2. 5 of casing materials if organic matter content was below 4.2 per cent and in pF 1. 3 to 1.8 if above 7.1%. 12. pF curve of a certain casing material could be draws from moisture content at various pF values by multiple regression equations provided texture, organic matter and calcium of the casing material are given. Optimum moisture range of the casing materials also could be estimated by the equation. 13. It was possible to improve the phyico-chemical characteristics of clay loam and sandy loam by addition of weathered spent compost although the effect was less than in the case of peat. Fresh weight of fruit bodies wsa increased by addition of weathered spent compost but its effect was not as remarkable as peat. Accordingly, further studies will be required.

• Journal of Yeungnam Medical Science
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• v.10 no.2
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• pp.369-379
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• 1993

The bone mineral density(BMD) of the lumbar spine (L2-L4) was measured by using dual energy x-ray absorptiometry(Norland XR26 DEXA) in 80 children aged between 2months and 15years (group 1 : 2month-1years, group 2 : 1year-5years, group 3 : 6years-10years, group 4 : 11years-15years). The correlation coefficient of BMD with age, body weight, height and Tanner stage were 0.696, 0.693, 0.717 and 0.636 respectively. There were significant difference in BMD($g/cm^2$) between group 1(BMD : $0.335{\pm}0.175$) and group 2(BMD : $0.627{\pm}0.200$). and group 3(BMD : $0.714{\pm}0.189$) and group 4(BMD : $0.873{\pm}0.163$)(P<0.05). There was no significant difference of BMD between boys and girls(P<0.05). BMD also increased significantly with development of Tanner stages(Tanner stage 1 : $0.547{\pm}0.234$, Tanner stage 2 : $0.783{\pm}0.136$, Tanner stage 3 : $0.998{\pm}0.080$ )(P<0.05). These data indicate that the BMD was correlated with age, body weight, height and Tanner stage significantly and BMD increased significantly during growth spurt occured in 1 to 4years of age and puberty.

• Journal of applied mathematics & informatics
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• v.35 no.3_4
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• pp.267-276
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• 2017

The purpose of this paper is to investigate the local asymptotic stability of equilibria, the periodic nature of solutions, the existence of unbounded solutions and the global behavior of solutions of the fractional difference equation $$x_{n+1}=\frac{^{{\alpha}x}n-1(k+1)}{{\beta}+{\gamma}x^p_{n-k}x^q_{n-(k+2)}}$$, $$n=0,1,{\dots}$$ where the parameters ${\alpha}$, ${\beta}$, ${\gamma}$, p, q are non-negative numbers and the initial values $x_{-(k+2)}$,$x_{-(k+1)}$, ${\dots}$, $x_{-1}$, $x_0{\in}\mathb{R}^+$.

• Journal of the Chungcheong Mathematical Society
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• v.21 no.4
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• pp.437-445
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• 2008

We show the existence of at least four nontrivial critical points of the $C^{1,1}$ functional f on the Hilbert space $H=X_0{\oplus}X_1{\oplus}X_2{\oplus}X_3{\oplus}X_4$, $X_i$, i = 0, 1, 2, 3 are finite dimensional, with f(0) = 0 when two sublevel subsets, torus with three holes and sphere, of f link, the functional f satisfies sup-inf variatinal linking inequality on the linking subspaces, the functional f satisfies $(P.S.)_c$ condition, and $f{\mid}_{X_0{\oplus}X_4}$ has no critical point with level c. We use the deformation lemma, the relative category theory and the critical point theory for the proof of main result.

• Bulletin of the Korean Chemical Society
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• v.28 no.11
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• pp.2003-2008
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• 2007

The aminolysis of diphenyl thiophosphinic chloride (2) with substituted anilines in acetonitrile at 55.0 oC is investigated kinetically. Kinetic results yield large Hammett ρX (ρnuc = ?3.97) and Bronsted βX (βnuc = 1.40) values. A concerted mechanism involving a partial frontside nucleophilic attack through a hydrogen-bonded, four-center type transition state is proposed on the basis of the primary normal kinetic isotope effects (kH/kD = 1.0-1.1) with deuterated aniline (XC6H4ND2) nucleophiles. The natural bond order charges on P and the degrees of distortion of 42 compounds: chlorophosphates [(R1O)(R2O)P(=O)Cl], chlorothiophosphates [(R1O)(R2O)P(=S)Cl], phosphonochloridates [(R1O)R2P(=O)Cl], phosphonochlorothioates [(R1O)R2P(=S)Cl], chlorophosphinates [R1R2P(=O)Cl], and chlorothiophosphinates [R1R2P(=S)Cl] are calculated at the B3LYP/ 6-311+G(d,p) level in the gas phase.

• The Korean Journal of Emergency Medical Services
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• v.7 no.1
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• pp.81-94
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• 2003

This study tries to examine the level of safety consciousness and first aid knowledge of 124 college students who attend non-public health departments in Gwangju from April 1 to 30, 2003 and apply the results of the study to curriculum. The results of this study are as follows; 1. On experiences of need of first-aid, 87.5% of respondents said 'yes' and there was a significant difference in the number of their siblings($x^2$ = 7.482, p = .048). 2. Sources of education of first aid were mostly at school(46.8%), no education(23.4%), through mass communication(22.6%) and by themselves(7.3%). There were significant differences by characteristics in sex($x^2$ = 30.230, p = .000), year($x^2$ = 10.821, p = .013) and mother's education($x^2$ = 18.932, p = .025). 3. Sources of information of first aid were mostly through TV(46.8%), followed by others (42.7%), newspapers(7.3%) and magazines(3.2%). 4. On the opinions of the most suitable period for educating first aid, elementary school was highest(41.9%), followed by kindergarten(29.0%), middle school(21.0%) and high school (8.1%) and there were significant difference by characteristics of subjects in sex($x^2$=9.689, p= .021) and year($x^2$=19.661, p= .000). 5. Score of knowledge level of safety consciousness was mean $71.58{\pm}12.05$ based on Likert 5-point scale with a full mark of 100 points and there was a significance only in current residence of subjects' general characteristics(F or t=3.894, p=.023). 6. Score of knowledge level of first aid was mean $62.73{\pm}13.29$ based on Likert 3-point scale with a full mark of 90 points and there was a significance only in residential type of subjects' general characteristics(F or t=3.058, p= .031). Although college students felt needs of first aid more than middle and high school students, it was found that their actual safety consciousness and knowledge level of first aid were low. Therefore, knowledge and ability should be developed to save human life from all kinds of emergencies and safety accident and first aid subjects should be separated in college curriculum and opportunity for actual education should be given.

• The Pure and Applied Mathematics
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• v.16 no.2
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• pp.167-178
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• 2009

In this paper, we obtain the generalized Hyers-Ulam stability of a Cauchy-Jensen functional equation f(x+y, z)-f(x, z)-f(y, z)=0, $$2f\;x,\;{\frac{y+z}{2}}-f(x,\;y)-f(x,\;z)=0$$ in the spirit of P. $G{\breve{a}}vruta$.

• Korean Journal of Mathematics
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• v.30 no.2
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• pp.403-412
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• 2022

In this paper, we introduce the following cubic-quartic functional equation of the form $$f(x+4y)+f(x-4y)=16[f(x+y)+f(x-y)]{\pm}30f(-x)+\frac{5}{2}[f(4y)-64f(y)]$$. Further, we investigate the general solution and the Ulam stability for the above functional equation in non-Archimedean spaces by using the direct method.

• The Korean Journal of Zoology
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• v.33 no.3
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• pp.337-345
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• 1990

The properties of three esterases (E2, E6 and E11) which were previously purified from Pieris rapae L. were determined and physiological role of E6 was inferred using immunological methods. Based on inhibitor study, all of the purified esterases were found to be carboxylesterases (EC 3.1.1.1). The Km values for E2, E6 and E11 were determined to be 6.89 X 10-$^4$M. 3.19 $\times$ l0-$^4$M and 3.69 X 10-$^4$M, respectively. The molecular weights of E2, E6 and E11 were estimated to be 42 KD, 81 KD and 174 KD, respectively. The isoelectric points of E2, E6 and E11 were estimated to be pH 5.54, pH 5.89 and pH 6.50, respectively. The concentration of E6 during development was highest at the late 5th instar larval stage and that according to organs at the same stage was highest in midgut. These results suggest that E6 might be a hydrolase involved in the digestion of dietary lipids.

• Journal of The Korean Society of Grassland and Forage Science
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• v.7 no.3
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• pp.162-167
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• 1987

This experiment was conducted to determine the effect of the feeding value for the wild legumes silage-making with additives. The chopped Kudzu (Puerarie thunbergii Bentham) of wild legumes was ensiled by the conventional method in the small experimental silo of 2 liters. The additives used in the present experiments were water (8%),water (8%) plus corn starch (3%) and water (8%) plus glucose (3%). These additives as well as that of control without additive were set up and these silage were compared with the conventional corn silage. The fermentative qualities and the characteristic of fiber (neutral detergent fiber, NDF; acid detergent fiber, ADF; acid detergent lignin, ADL) of silage produced was determined by chemical analysis, and dry matter digestibility (DMD) was evaluated by pepsin-cellulase technique. The results obtained are summarized as follows: 1 The weight of Kudzu silage was lost under the 10% for all the treatments. 2 In degree of pH for the Kudzu silages with glucose, starch, control and water treatments were high 3.80,4.04,4.57 and 5.34, respectively.