• Analytical Science and Technology
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• v.16 no.3
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• pp.249-260
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• 2003

The disinfection of drinking water to control microbial contaminants results in the formation of secondary chemical contaminants, DBPs (disinfection by-products). It was studied the formation pattern of DBPs in drinking raw water after hypochlorite, chlorine disinfectant, was added in this study. It was determined TOC (total organic carbon), residual chlorine, turbidity and DBPs in raw water from Han-river during 1~14 days. Total DBPs was $101.3ng/m{\ell}$ (789.6 nM) after 7days and THMs (trihalomethanes) are the dominant portion of 69%. HAAs (haloacetic acids) and chloral hydrate were determined 19% and 10% respectively, and HANs (haloacetonitriles), HKs (haloketones) and chloropicrin were analyzed in trace level. Chloroform occupied about 89% in total THMs in concentration of $61.5ng/m{\ell}$, 95% of HANs was DCAN (dichloroacetonitrile) in $0.72ng/m{\ell}$, 50% of HAAs was TCAA (trichloroacetic acid). On the study of relationship in formation among the DBPs, HANs forms with THMs competitively to the point of the concentration of $40ng/m{\ell}$ of THMs. For HAAs, it did not show the prominent tendency. But it was observed that the compounds of large oxidation state are formed at first, and becomes to the compounds of low oxidation states.

• Analytical Science and Technology
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• v.17 no.1
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• pp.69-81
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• 2004

The formation pattern of DBPs (disinfection by-products) in raw water treated with hypochlorite, chlorine disinfectant was studied. TOC (total organic carbon), residual chlorine, turbidity and 14 DBPs in raw water from Han-river and Nakdong river during 1 ~ 14 days were determined. Total DBPs in Han river was 101.3 ng/mL (789.6 nM) after 7days and THMs (trihalomethanes) are the dominant portion of 68%. HAAs (haloacetic acids) and chloral hydrate were determined 19% and 10% respectively. In Nakdong river total DBPs was 98.4 ng/mL (678.6 nM) and dominant class was HAAs. (55.8 ng/mL, 57%) THMs(34%) and N-compounds like HANs (haloacetonitriles, 5%) and chloropicrin were increased. It may be explained that high concentration of NH4-N in Nakdong river react with chlorine produced chloramine and this formed different pattern of DBPs. As a result, total DBPs formation pattern depends on raw water and disinfectant and in generally the initial concentration of acidic HAAs was high and THMs was increased gradually.

• KIPS Transactions on Software and Data Engineering
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• v.6 no.8
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• pp.379-384
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• 2017

In real software business environment, there are required to validate software quality in diverse usage range of software for many small & medium companies. Software quality means both qualities of production and process. In our situation, we focus on better process quality of a test organization than a whole organization. But even the original test maturity model (TMM) does not enough to apply with our domestic venture/small & medium companies. To solve this problem, we suggest the simplified test maturity model for our companies. We redefine this simplified model with the original TMM and a test process improvement next (TPI next) model. The previous models just have provided each definition of maturity level, goal and activity per each level, which not exists an assessment guideline and a formal assessing procedure. Due to this reasons, an assessor is difficult to assess the test organization without them. this paper suggest an assessment guideline of the simplified TMM and also define the procedure which is included with activities and byproducts. With these assessment guideline, an assessor can work possible to formally assess test organizations of small & medium companies, and with self assessment guideline they can be correctly provision before assessment of their organizations.

• Korean Journal of Heritage: History & Science
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• v.53 no.2
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• pp.24-35
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• 2020

This study aims to identify the relationship between termite-damaged cultural heritage sites and the 'Forest Tending Project' based on a comprehensive survey of the status of damage caused by termites and of the Forest Tending Project. It was observed that the Forest Tending Project started in 2004 as a five-year policy project covering over 59% of the nation's forests, which showed the maximum value in 2009 and then gradually decreased. Since then, increased damage to national cultural heritage sites by termites has been confirmed and counter measures have been expanded since 2012. Also, as a result of the National Research Institute of Cultural Heritage surveying the status of termite damage in national cultural heritage sites over these six years, it was identified that about 98% of investigated cultural heritage sites were damaged by termites, about 78% of them were adjacent to forests, and that all 46 national cultural heritage sites which had been included in the 2008 Forest Fire Prevention Cultural Heritage Afforestation Project were damaged by termites. Therefore, it is claimed that the number of termite-damaged cultural heritage sites has increased after an extensive Forest Tending Project was applied on a national scale, and it seems that all cultural heritage areas close to forests are particularly subject to termite-damage due to the number of tree stumps and lumber byproducts which can serve as habitats for the pests.

• Journal of Food Hygiene and Safety
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• v.29 no.4
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• pp.363-369
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• 2014

This study was conducted to investigate the quality characteristics of tofu prepared with addition of cowpea meal (CPM). Any significant difference of L-value between control CPM-O and treatment CPM-I, CPM-II and CPM-III could not be seen as addition ratio of CPM increases (p < 0.05). The b-value of CPM-III (75%) has shown the least value of 14.26, and it has decreased as addition ratio of CPM increases. The result of texture profile did not show any significant difference between control CPM-O and CPM-Iexcept in the case of cohesiveness. The pH range of treatments was 6.36~6.52, which showed no significant difference from controls. The values of turbidity were 1.46~1.81, which had increasing trend as addition ratio of CPM increases. The total bacterial count of CPM-III was $4.40{\times}10^2CFU/g$, which showed significant difference from the control. No Esterichia coli was detected in the control and the treatments. The result of sensory analysis of the treatment CPM-I did not show any significant difference from the control, which implied the treatment CPM-Iwas found to be suitable at the tofu making using byproducts of cowpea-jelly making. Isoflavone glycoside (IG) was contained more on the order of genistin, daidzin, and glycitin, and the content decreased significantly as addition ratio of CPM increases. The content of isoflavone-aglycone (IA) was less than IG, but showed similar behavior of addition ratio of CPM.

• Journal of the Korean Society of Food Science and Nutrition
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• v.35 no.7
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• pp.897-902
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• 2006

This study was carried out to investigate the possibility for utilization of waste materials and the characteristics of pork by feeding citrus byproducts. The groups consisted of the pork without citrus byproduct (TB-0) and the pork fed with 6% and 10% citrus byproduct during growing and fattening period (TB-1). The contents of moisture, crude protein, crude fat, crude ash, vitamin $B_1$ and $B_2$, total amino acids, and caloric were not significantly different between TB-0 and TB-1 (p>0.05). The contents of cholesterol and the magnesium of TB-1 were lower than those of TB-0. Palmitic acid was the most abundant among saturated fatty acids while oleic acid was the most abundant among unsaturated fatty acids in both groups. In case of sensory score, the color and aroma of raw meat and taste, texture, juiciness and palatability of boiled meat were not influenced by feeding of citrus byproduct. But the flavor preference of boiled meat of TB-1 was higher than that of TB-0.

• Journal of Science and Technology Studies
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• v.17 no.2
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• pp.113-171
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• 2017

Science and engineering college students, so-called engineering students, account for nearly half of Korean university students. Existing research on younger generations poses a question of young generation after the financial crisis as a 'genuine' survivalist who carries out 'passionate labor' to pursue 'ordinary life' and 'banal stability'. They are diagnosed as failing to "locate the course of their lives in relation to a larger being that transcends self". But is there a value that can replace the survival value in front of us today, which is possible to be practiced and narrated by the young generation of Korea, especially the engineering students? What value (if any) is not captured by survival value, and what mechanisms and processes can and can easily be used by engineering students? Our research uses interviews conducted at one research-centered science and engineering university in a local metropolitan city, Korea. In conclusion, we emphasize that a transformed version of developmental nationalism, in which individual scientists/engineers pursue their 'authentic' passion and unintentionally contribute to the development of the nation through byproducts of their research, exerts strong influence upon the formation of young engineering students' narratives linking their selfhood and the good.

• Journal of Radiation Industry
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• v.2 no.1
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• pp.21-26
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• 2008

Although seafood cooking drips were the byproducts from the fishery industry it was known that the cooking drips had many nutrients and could be used as functional materials. Previously, the physiological properties of cooking drips were shown to be increased by a gamma irradiation. But, there was no report on the safe for the genotoxicity on the irradiation. In this study, the genotoxicity of the cooking drips from Hizikia fusiformis, Enteroctopus dofleni and Thunnus thynnus was evaluated by the Ames test (Salmonella typhimurium reversion assay) and the SOS chromotest. The results from all samples were negative in the bacterial reversion assay with S. typhimurium TA98, TA100. No mutagenicity was detected in the assay, both with and without metabolic activation. The SOS chromotest also indicated that the gamma-irradiated seafood cooking drips did not show any mutagenicity. Therefore, this study indicated that gamma irradiation could be used for the hygiene, functional properties and processibility of seafood cooking drips.

• Korean Chemical Engineering Research
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• v.57 no.6
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• pp.758-762
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• 2019

Sodium borohydride,$NaBH_4$, has many advantages as hydrogen source for portable proton exchange membrane fuel cells (PEMFC). When PEMFC is used for marine use, $NaBH_4$ hydrolysis using seawater is economical. Therefore, in this study, hydrogen was generated by using seawater instead of distilled water in the process of hydrolysis of $NaBH_4$. Properties of $NaBH_4$ hydrolysis reaction using activated carbon supported Co-B/C catalyst were studied. The yield of hydrogen decreased as $NaBH_4$ concentration and NaOH concentration were increased during $NaBH_4$ hydrolysis using sea water. At higher concentrations of $NaBH_4$ and NaOH, byproducts adhered to the surface of the catalyst after hydrolysis reaction using sea water, reduced hydrogen yield compared to distilled water. The activation energy of $NaBH_4$ hydrolysis is 59.3, 74.4 kJ/mol for distilled water and sea water, respectively. In order to increase the hydrogen generation rate in seawater as high as distilled water, the reaction temperature has to be increased by $80^{\circ}C$ or more.

• Resources Recycling
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• v.30 no.6
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• pp.19-27
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• 2021

Electrically conductive mortar used in industrial carbon material byproducts was manufactured and analyzed in this study. The contents of the carbon material and mixed water were controlled, and the distance between electrodes was set to 0.42 m and 0.88 m. The carbon material was graphite with a layered structure. The carbon material was used as fine powder and aggregate substitutes according to particle size. The average particle sizes of each materials were 18.4㎛ and 546.1 ㎛ and the electrical conductivities were 62.3 S/m and 32.5 S/m, respectively. To maintain similar mortar flow in each sample, the water content was increased with increasing carbon material, and accordingly, the porosity showed an increasing trend. When electrode distance of the mortar (week 6) was 0.42 m, the voltage-current values were 342 V-1.48 A (S20) and 349 V-1.44 A (S30). For electrode distance of 0.88 m, these values were 513 V-0.98 A (S20) and 500 V-1.01 A (S30). The exothermic properties improved with increasing carbon material content and decreasing electrode distance.