• Journal of Environmental Science International
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• v.16 no.12
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• pp.1431-1437
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• 2007

Cobalt titanates($CoTiO_x$), such as $CoTiO_3$ and $Co_2TiO_4$, have been synthesized via a solid-state reaction and characterized using X-ray diffraction(XRD) and X-ray photoelectron spectroscopic(XPS) measurement techniques, prior to being used for continuous wet trichloroethylene(TCE) oxidation at $36^{\circ}C$, to support our earlier chemical structure model for Co species in 5 wt% $CoO_x/TiO_2$(fresh) and(spent) catalysts. Each XRD pattern for the synthesized $CoTiO_3$ and $Co_2TiO_4$ was very close to those obtained from the respective standard XRD data files. The two $CoTiO_x$ samples gave Co 2p XPS spectra consisting of very strong main peaks for Co $2p_{3/2}$ and $2p_{1/2}$ with corresponding satellite structures at higher binding energies. The Co $2p_{3/2}$ main structure appeared at 781.3 eV for the $CoTiO_3$, and it was indicated at 781.1 eV with the $Co_2TiO_4$. Not only could these binding energy values be very similar to that exhibited for the 5 wt% $CoO_x/TiO_2$(fresh), but the spin-orbit splitting(${\Delta}E$) had also no noticeable difference between the cobalt titanates and a sample of the fresh catalyst. Neither of all the $CoTiO_x$ samples were active for the wet TCE oxidation, as expected, but a sample of pure $Co_3O_4$ had a good activity for this reaction. The earlier proposed model for the surface $CoO_x$ species existing with the fresh and spent catalysts is very consistent with the XPS characterization and activity measurements for the cobalt titanates.

• Journal of Communications and Networks
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• v.7 no.3
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• pp.325-336
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• 2005

Mobile ad hoc networks (MANET) are composed of moving wireless hosts which, within range of each other, form wireless networks. For communication to occur between hosts that are not within each other's range, routes involving intermediate nodes must be established; however, since the hosts may be in motion, a host that was part of a route may move away from its upstream and downstream partners, thus breaking the route. In this paper, we propose anticipated route maintenance (ARM) protocol with two extensions to route discovery based routing scheme: Extend the route when nodes on a link move apart from each other and they have common neighbor that can be 'inserted' in the path, and shrink route when a node discovers that one of its neighbor which is not the next hop is also on the same route several hops later on. By utilizing only local geographic information (now a part of some route finding algorithms), a host can anticipate its neighbor's departure and, if other hosts are available, choose a host to bridge the gap, keeping the path connected. We present a distributed algorithm that anticipates route failure and performs preventative route maintenance using location information to increase a route lifespan. The benefits are that this reduces the need to find new routes (which is very expensive) and prevents interruptions in service. As the density of nodes increases, the chance to successfully utilize our route maintenance approach increases, and so does the savings. We have compared the performance of two protocols, pure dynamic source routing (DSR) protocol and DSR with ARM. The simulation results show how ARM improves the functionality of DSR by preventing the links in the route from breaking. Packets delivery ratio could be increased using ARM and achieved approximately $\100%$ improvement. The simulations clarify also how ARM shows a noticeable improvement in dropped packets and links stability over DSR, even though there is more traffic and channel overhead in ARM.

• Journal of Communications and Networks
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• v.14 no.4
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• pp.451-460
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• 2012

Natural disasters often lead to regional failures that can cause network nodes and links co-located in a large geographical area to fail. Novel approaches are required to assess the network vulnerability under such regional failures. In this paper, we investigate the vulnerability of networks by considering the geometric properties of regional failures and network nodes. To evaluate the criticality of node locations and determine the critical areas in a network, we propose the concept of ${\alpha}$-critical-distance with a given failure impact ratio ${\alpha}$, and we formulate two optimization problems based on the concept. By analyzing the geometric properties of the problems, we show that although finding critical nodes or links in a pure graph is a NP-complete problem, the problem of finding critical areas has polynomial time complexity. We propose two algorithms to deal with these problems and analyze their time complexities. Using real city-level Internet topology data, we conducted experiments to compute the ${\alpha}$-critical-distances for different networks. The computational results demonstrate the differences in vulnerability of different networks. The results also indicate that the critical area of a network can be estimated by limiting failure centers on the locations of network nodes. Additionally, we find that with the same impact ratio ${\alpha}$, the topologies examined have larger ${\alpha}$-critical-distances when the network performance is measured using the giant component size instead of the other two metrics. Similar results are obtained when the network performance is measured using the average two terminal reliability and the network efficiency, although computation of the former entails less time complexity than that of the latter.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.15 no.4
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• pp.303-311
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• 1982

Sensory evaluations of synthetic extracts prepared on the analytical data in the previous papers (Yang and Lee, 1979, 1930-a, 1980-b, 1982) were undertaken to determine the origin of the taste of wild common carp, Cyprinus carpio, and Korean snakehead: Channa argus. Taste panel assessments of synthetic extracts prepared with each extractive component omitted were carried out by a triangle difference test, and changes in taste profile were assessed. The synthetic extracts, prepared with about 40 pure chemicals based on the analytical data from the species satisfactorily revealed the natural taste of the original extracts except slight difference in meaty taste and mildness. From the results of omission test the major components which contribute to produce the taste of the species were assessed as follows: glycine, glutamic acid, arginine, lysine, threonine, alanine, IMP, inosine, hypoxanthine, glucose, succinic acid, $Na^{+},\;Cl^{-}\;and\;PO_{4}^{3-}$ in common carp: glycine, alanine, glutamic acid, IMP, Na+ and $PO_{4}^{3-}$ in Korean snakehead.

• Fisheries and Aquatic Sciences
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• v.18 no.1
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• pp.57-63
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• 2015

Effects of rearing density on growth and survival of the polychaete rockworm Marphysa sanguinea have been investigated in order to develop rearing techniques for this species. This study was examined over a nine-month period in the Fisheries Science and Technology Center of Pukyong National University. Three rockworm densities, 500, 1,000 and $2,000worms{\cdot}m^{-2}$ with weight ranges of < 0.5 g, 0.6-1.5 g, and 1.6-2.5 g, and the no feed control treatment, were stocked in triplicate $0.10m^2$ boxes with sand bottoms. Growth rates were checked with 15 randomly sampled rockworms from each box at months 3, 6 and 9. Results showed that SGRs in all treatments were higher during the first period (0-3 months) than the second (3-6 months) and third periods (6-9 months) for all treatment densities, while SGRs decreased with increasing density. However, survival and growth of worms at high density was not better than low density, but daily biomass production in medium and high density groups was $6.28gm^{-2}day^{-1}$ for the rockworms of 0.6-1.5 g with $2,000inds{\cdot}m^{-2}$, and $12.6gm^{-2}day^{-1}$ for group between 1.6-2.5 g with $2,000inds{\cdot}m^{-2}$, and $14.7gm^{-2}day^{-1}$ for the group of individuals <0.5 g with $1,000inds{\cdot}m^{-2}$. Results showed that M. sanguinea can be one of the most suitable species to commercially exploit in a farming system. In particular, specified densities permit elevated pure production.

• Asian-Australasian Journal of Animal Sciences
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• v.17 no.2
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• pp.278-282
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• 2004

Compost is used mainly as an organic fertilizer, but it is also used as bedding material for cattle. Dairy cattle have been identified as a main reservoir of pathogenic Escherichia coli O157:H7. Further, E. coli is regarded as an environmental pathogen that causes bovine clinical mastitis. Hence, its growth in compost spread or compost bedding should be avoided. Physical and chemical conditions, available nutrients and microflora in compost change greatly during the composting process. Since pathogen growth in compost seems to be related to these changes, we assessed the possibility of E. coli growth in compost samples collected at 0, 7, 13, 22, 41, 190 and 360 d. Cattle waste composts with and without added tofu residue were collected from static piles and immediately air-dried. Compost samples were inoculated with a pure culture of E. coli, the moisture content was adjusted to 50%, and the samples were incubated for 5 d at $30^{\circ}C$. The numbers of E. coli in compost before and after incubation were determined by direct plating on Chromocult coliform agar. Almost all compost samples supported E. coli growth. Samples collected during or immediately after the thermophilic phase (day 7) showed the highest growth. Growth in samples more than 13 d old were not significantly different from those of aged compost samples. The addition of tofu residue gave a higher growth than its absence in younger samples collected prior to 13 d. To minimize the risk of environmental mastitis, the use of compost in the initial stage of the process is better avoided.

• Asian-Australasian Journal of Animal Sciences
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• v.13 no.3
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• pp.381-389
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• 2000

The Jindo is a Korean native dog, well-known for its hunting and guarding abilities. When he gives his devotion to one individual, he gives it whole-heartedly. He is not tempted easily and impetuous. The breed was not developed. but the dog retained their original qualities -loyal, alert, fearless, obedient, watchful, intelligent, energetic- to survive in the harsh environment of the Jindo island. The dog had been spread over the entire Korean peninsula from the time unknown, and the ones in the Jindo island, isolated until lately, survived and maintained their original characteristics. They are now spread over the entire Jindo County consisted of many islands, whence the breed name came. The Jindo comes in a variety of colors and color combinations, with the fawn and white colorings predominant. The dog is one of the Korean natural monuments, protected by law since early 1960s. The Jindo gained official approval by the Federation Cynologique Internationale as a hunting dog. Apart from the basic housetraining, the dog rarely gets training. Many people have attempted to preserve its pure bloodlines and original qualities. Today, there are a total of 10,356 Jindoes being raised over the entire Jindo County, and many more are kept elsewhere. A research into genetic characteristics of the Jindo is now going on, using the technique of isozyme electrophoresis. The Jindo Dog Breeding Management Center has been reinforced lately, and in addition to their routines, the Center is to work on the breeding of the Jindo. Efforts should be made in the future to produce stable, trustworthy Jindoes according to their proposed use and to modify their temperament in order to make it more widely acceptable as a pet and companion dog in the strangers home.

• Journal of the Korean Chemical Society
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• v.21 no.5
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• pp.372-378
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• 1977

The following new techniques have been developed: (A); To a 500ml of sample water, it was adjusted pH 10 with ammonia-anmonium citrate, added 10ml of 1${\%}$ sodium diethyldithiocarbamate and extracted three times with 10ml of CHCl3. The extract was shaken with 10ml of 0.05N $HCl-4{\times}10^{-4}M\;HgCl_2$. The aqueous solution was added 2ml of 2N KCl and washed two times with 10ml of pure $CHCl_3$, and then recorded square wave polarograms. (B); To a 500ml of sample water adjusted pH 10 with ammonia-ammonium citrate, it was added 2ml of 1${\%}$ 8-hydroxyquinoline and extracted three times with 10ml $CHCl_3$. The separated $CHCl_3$ phase was shaken with 10ml of 0.2 N HCl. The aqueous solution was recorded polarograms directly. These methods can be used for determination of the ppb order of metal in water with an error of ${\pm}10{\%}$. The method (B) can not be used for the determination of zinc on account of the free 8-hydroxyquinoline.

• Asian-Australasian Journal of Animal Sciences
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• v.16 no.9
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• pp.1332-1338
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• 2003

This study was undertaken to examine the influence of soluble non-starch polysaccharides on growth performance, mucin secretion, and endogenous amino acid flows in weaner pigs. Different levels (0, 4 and 7.5%) of purified corn arabinoxylan (AX) or barley $\beta$-glucan extract (BG) were substituted for cellulose in a purified diet based on starch, sucrose and enzymatically hydrolyzed casein. All diets contained titanium oxide as an indigestible marker. Each experimental diet was fed to five, 6-wk old weaner pigs for 21 days. Average daily gain (p<0.05) and feed conversion ratio (p<0.01) were improved with dietary inclusion of 7.5% AX and BG, indicating high degradation rates of AX and BG in pigs. Crude mucin contents and endogenous nitrogen flow were increased (p<0.05) with increased levels of AX, but not with BG. Numerical increases in endogenous amino acid flow (EAAF) were observed with increased levels of AX but no definite trend with BG. Endogenous amino acid flow in pigs fed mixed NSP diets (4% BG and 3.5% cellulose) was significantly higher (p<0.05) than those fed 7.5% BG diets. Among diets containing pure sources of soluble non-starch polysaccharides, endogenous amino acid flows were highest in 7.5% AX (p<0.05), intermediate in BG, and lowest in control diet. Increased flows (p<0.01) of threonine, proline and serine in pigs fed 7.5% AX diets are consistent with the increased flow of crude mucin determined in this treatment. In conclusion, mucin and endogenous amino acid flows were increased with dietary inclusion of AX, which could be related to its physicochemical property, particularly its high water-holding capacity. In contrast, $\beta$-glucan, due to its high degradation rate in pig, may be considered as unimportant factor in inducing mucin and endogenous amino acid secretions, at least at levels such as those used in this study.

• Asian-Australasian Journal of Animal Sciences
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• v.19 no.7
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• pp.931-937
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• 2006

The full-length cDNA of the porcine SMPX gene was obtained by the rapid amplification of cDNA ends (RACE). The nucleotide sequences and the predicted protein sequences share high sequence identity with both human and mouse. The promoter of SMPX was sequenced and then analyzed to find the promoter binding sites. The reverse transcriptase-polymerase chain reaction (RT-PCR) revealed that SMPX has a high level of expression in heart and skeletal muscle, a very low expression in lung and spleen and no expression in liver, kidney, fat and brain. Moreover, SMPX has a differential expression level in skeletal muscle, the expression in 65-day embryos being higher than other stages. The porcine SMPX was mapped to SSCXp24 by using a somatic cell hybrid panel (SCHP) and was found closely linked to SW1903 using the radiation hybrid panel IMpRH. An A/G single nucleotide polymorphism (PCR-RFLP) in the 3'-untranslated region (3'-UTR) was detected in eight breeds. The analysis of allele frequency distribution showed that introduced pig breeds (Duroc and Large White) have a higher frequency of allele A while in the Chinese indigenous pig breeds (Qingping pig, Lantang pig, YushanBlack pig, Large Black-White pig, Small Meishan) have a higher frequencies of allele G. The association analysis using an experimental population (188 pigs), which included two cross-bred groups and three pure-blood groups, suggested that the SNP genotype was associated with intramuscular fat content.