• International Journal of Reliability and Applications
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• v.8 no.2
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• pp.137-151
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• 2007

Posbist reliability of typical systems is preliminarily discussed in Cai (1991). In this paper, we focus on the posbist reliability analysis of some typical systems in depth. First, the lifetime of the system is dealt as a fuzzy variable defined on the possibility space (U, ${\phi}$, $P_{oss}$) and the universe of discourse is expanded from (0, $+{\infty}$) to ($-{\infty},\;+{\infty}$). Then, a concrete possibility distribution function of the fuzzy variable is given, i.e., a Gaussian fuzzy variable. Finally, posbist reliability of typical systems (series, parallel, series-parallel, parallel-series, cold redundant system) is deduced. The expansion makes the proofs of some theorems straightforward and allows us to easily obtain the posbist reliability of typical systems. To illustrate the method a numerical example is given.

• Bulletin of the Korean Mathematical Society
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• v.60 no.6
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• pp.1673-1685
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• 2023

Inspired by Hongjie Dong and Qi S. Zhang's article [3], we find that the analyticity in time for a smooth solution of the heat equation with exponential quadratic growth in the space variable can be extended to any complete noncompact Riemannian manifolds with Bakry-Émery Ricci curvature bounded below and the potential function being of at most quadratic growth. Therefore, our result holds on all gradient Ricci solitons. As a corollary, we give a necessary and sufficient condition on the solvability of the backward heat equation in a class of functions with the similar growth condition. In addition, we also consider the solution in certain L^p spaces with p ∈ [2, +∞) and prove its analyticity with respect to time.

• Journal of Animal Science and Technology
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• v.51 no.4
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• pp.329-336
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• 2009

The objective of this study was to investigate the relationship between measurements of color and water-holding capacity (WHC) in pork loin. A total of 419 pork loins were sampled from crossbred (Landrace$\times$Jeju native black pig) F2 pigs at a commercial slaughter house. Meat color measurements (CIE $L^*$, $a^*$, $b^*$), chroma ($C^*$) and hue angle (h) were measured with the Minolta Chromameter and WHC was measured by filter paper fluid, drip loss and cooking loss. Also pH, moisture content and crude fat content were measured at 24 hr postmortem. CIE $L^*$, $b^*$ and h values had positive correlation with drip loss (r=0.52, 0.42), but CIE $a^*$ and $C^*$ values were not related to drip loss. Results showed that CIE $L^*$, $b^*$, and h color system was better than CIE $L^*$, $a^*$, $b^*$ color system to predict WHC, especially drip loss. pH was negatively correlated to drip loss (-0.42) and CIE $L^*$ (-0.67). Although CIE $L^*$ and pH were correlated to drip loss, the accuracy of their estimates for drip loss was 27% and 17%, respectively. Consequently, it was confirmed that meat color and WHC were not perfectly related and suggested that CIE $L^*$, $b^*$, and h color space should not be used independently to predict WHC of pork loin.

• Journal of Microbiology and Biotechnology
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• v.5 no.1
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• pp.26-30
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• 1995

The cytoplasmic endo-$\beta$-l, 4-glucanase (endoglucanase) was purified from cell extracts of Escherichia coli (pBS1) transformant carrying the Bacillus subtilis endo-$\beta$-l, 4-glucanase gene after full growth, and its molecular weight was found to be 52 kilodaltons (kDa). The endo-$\beta$-l, 4-glucanase isolated from the periplasmic space was smaller than 52-kDa cytoplasmic enzyme. The 52-kDa endoglucanase was found to be cleaved in the periplasm and finally converted to 34.5-kDa protein. Small amounts of both 52-kDa and 34.5-kDa proteins were secreted into the culture broth. The cleavage took place in the C-terminal portion of the enzyme. The N-terminal amino acid residues of both 52-kDa and 34.5-kDa enzymes were determined to be the same, Ala, the 30th residue of the primary translation product. Cleavage of the C-terminal portion showed to have no significant effect on the basic enzyme properties.

• The Korean Journal of Pain
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• v.10 no.2
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• pp.231-234
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• 1997

Background: The aim of this study was to examine the precise spreading pattern of contrast media in small increments in rabbits. Following pentobarbital anesthesia, the epidural puncture was done surgically with a blunt hook. Methods: The tip of epidural catheter was located at the mid-portion of T7 and T12, in the T7 group (n=7) and T12 group (n=8), respectively. Injection of the contrast media was started at 0.1 mL/kg and increased by 0.1 mL/kg up to a maximum of 0.6, mL/kg, under fluoroscopy. Results: In both groups, the extent of spread increased continuously as a Starling resistor with increasing injected volume(T7 group: $y=4.0+41.8x-28.1x^2$, T12 group: $y=0.2+57.7x-43.5x^2$) the total spread of contrast media was similar. The contrast media spread equally, both rostral and caudal, from catheter tip in T7 group; media spread approximately twice as far rostral as compared to caudal in T12 group (P<0.05). Conclusions: In rabbits, the position of epidural catheter tip should be positioned 2~3 segments below the aimed segment in lower thoracic or lumbar region, whereas in mid-thoracic region it should be positioned close to the level of aimed segment. Rabbits have relatively small epidural space therefore, the volume of injectant should be carefully determined with the suggested equations of this study.

• Asian-Australasian Journal of Animal Sciences
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• v.29 no.5
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• pp.739-746
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• 2016

A total of 152 pig farms were randomly selected from the five provinces in South Korea. During the experiment, the average temperature and relative humidity was $24.7^{\circ}C$ and 74% in summer and $2.4^{\circ}C$ and 53% in winter, respectively. The correlation between floor space allowance (FSA) and productivity index was analyzed, including non-productive sow days (NPD), number of weaners (NOW), survival rate (SR), appearance rate of A-grade pork (ARA), and days at a slaughter weight of 110 kg (d-SW) at different growth stages. The objectives of the present study were i) to determine the effect of FSA on the pig productivity index and ii) to suggest the minimum FSA for pigs based on scientific baseline data. For the pregnant sow, NPD could be decreased if pregnant sows were raised with a medium level (M) of FSA (3.10 to $3.67m^2/head$) while also keeping the pig house clean which improves hygiene, and operating the ventilation system properly. For the farrowing sows, the NOW tended to decrease as the FSA increased. Similarly, a high level of FSA (H) is significantly negative with weaner SR of farrowing sows (p-value = 0.017), indicating this FSA tends to depress SR. Therefore, a FSA of 2.30 to $6.40m^2/head$ (very low) could be appropriate for weaners because a limited space can provide a sense of security and protection from external interruptions. The opposite trend was observed that an increase in floor space (> $1.12m^2/head$ leads to increase the SR of growing pigs. For the fattening pigs, H level of FSA was negatively correlated with SR, but M level of FSA was positively correlated with SR, indicating that SR tended to increase with the FSA of 1.10 to $1.27m^2/head$. In contrast, ARA of male fattening pigs showed opposite results. H level of FSA (1.27 to $1.47m^2/head$) was suggested to increase productivity because ARA was most affected by H level of space allowance with positive correlation ($R^2=0.523$). The relationship between the FSA and d-SW of fattening pigs was hard to identify because of the low $R^2$ value. However, the farms that provided a relatively large floor space (1.27 to $1.54m^2/head$) during the winter period showed d-SW was significantly and negatively affected by FSA.

• Journal of Korean Society of Water and Wastewater
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• v.20 no.1
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• pp.86-93
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• 2006

In the drinking water treatment, the aesthetic and color problem are caused by the manganese which is occurring and present in the surface, lake and ground water. The most common treatment processes for removing manganese are known for oxidation followed by filtration. In this study, the manganese sand process was used for removing manganese with river bank filtrate as a source. In the manganese sand process, the residual chlorine and pH are important factors on the continuous manganese oxidation. In addition, space velocity (SV) and alum dosage are play a role of manganese removal. Even though manganese removal increased with increasing chlorine concentration, the control of residual chlorine is actually difficult in this process As the results of tests, the residual chlorine concentration as well as manganese removal were effectively achieved at pH 7.5. The optimum attached manganese concentration on manganese sand was confirmed to 0.3mg/L by the experimental result of a typical sand converting to manganese sand.

• Korean Journal of Poultry Science
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• v.38 no.1
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• pp.1-4
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• 2011

A 35-day trial was conducted to examine the influence of floor density on the behaviour of broiler chickens. Day-old male broilers (n=756) were randomly assigned to one of four stocking densities (6 replicates of n=13, 25, 38 and 50) in 24 identical 2.6 $m^2$ pens. These stocking densities were coded very low (VL), low (L), medium (M) and high (H) and contained a floor space allowance per bird of 2,000 $cm^2$, 1,000 $cm^2$, 667 $cm^2$ and 500 $cm^2$, respectively. Scan sampling of all groups was carried out at 15-min intervals during two 1-h periods (10.00 h~11.00 h and 14.00 h~15.00 h) for five days each week. The numbers of birds engaged in different behavioural activities were recorded. It was found that the most common behaviour in all densities was lying. There was no clear effect of density during wks 1~4 of the trial, but in wk 5 birds in the L, M and H groups showed lower levels (P=0.07) of lying behaviour when compared to birds in the VL group suggesting that an increase in animal density results in decreased opportunities for undisturbed rest. This observation is supported by standing and walking behaviour, which was lower (P<0.05) in the VL group in wk 5. Foraging behaviour measured in the study by the numbers of birds pecking the ground declined as the trial progressed, but scratching increased in 2 wk then decreased. Birds in the VL group showed higher (P<0.05) level of pecking the ground behaviour compared to birds in the L, M and H groups, but scratching behaviour higher (P<0.05) and lower (P<0.05) in VL of 1 wk and 2 wk respectively. However, a peak in aggressive behaviour was observed in wk 2 and birds in the VL group showed less (P<0.05) agonistic behaviour than birds in the H and M groups. Other behaviours (dustbathing, preening, eating or drinking) were not influenced (P>0.05) by stocking density.

• Korean Journal of Crystallography
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• v.10 no.1
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• pp.33-38
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• 1999

The complex [Ni(L2)(H2O)]Cl·H2O (1) (L2=3,14-dimethyl-2,6,13,17-tetraazartricyclo [14,4,01.18,07.12]docosane-N-acetic acid) has been synthesized and characterized by X-ray crystallography. 1 crystallizes in the triclinic system, space group P, with a=11.274(1), b=13.851(1), c=17.159(6) , α=90.24(2), β=101.10(2), γ=92.11(1)o V=2682.5(11) 3, Z=4, R1=0.042 and wR2=0.111 for 9432 observed reflections with [I>2σ(I)]. The central nicke(II) ion is six-coordinated octahedral geometry with bonds to the four amine nitrogen atoms the carboxylic oxygen atom of the macrocyclic ligand and to the water molecule occupying a position trans to the pendant arm.

• 한국생물공학회:학술대회논문집
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• 2003.04a
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• pp.445-449
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• 2003

As for the purpose, we first introduce an random mutation into wild-type gene to expand a mutation space, and then further recombine the mutant genes by staggered extension process PCR. As a result, we obtained the best clones 6-52 that showed a high activity and stability, from a round of error prone and staggered extension process PCR. The purified enzyme showed a similar pH stability to the wild-type enzyme and reveal a slightly high optimum pH at 12. In the optimum temperature, an identical dependency was also showed and a quite high stability in the thermal stability was obtained. Along with this, the enzyme was also stable at a reaction that supplement with a 15 % of ethanol as an additive. The addition of other solvents and surfactants did not improve the reaction and thus resulted in a similar profile to those of wild-type enzyme. The specific activity on the target compound rac-ketoprofen ethyl ester was calculated to be about 85, 000 unit, and the kinetic constants Km and Vmax were determined to be 0.2 mM and 90 mM/mg-protein/min respectively. The deduced amino acid alignment with the wild type enzyme revealed five mutations at L120P, I208V, T249A, D287H and T357A. Based on these observations, the site directed mutagenesis to delineate the mutagenic effect is under progress.