• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.2
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• pp.52-57
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• 2001

ln this study, the questionnaire survey was performed to obtain the basic data on current situations and challengeable aspects of vermicomposting industries. The questionnaire contained the four main categories such as vermicomposting facilities, feeling marerials, earthworm breeding and cast handling. The results was summarized as followings: 1. Vermicomposting facilities area was becoming larger, and earthworm feed was also expending to various organic sludges. These trends showed that Vermicomposting is being enlightened to treat and recycle the organic wastes in Korea. 2. Present Vermicomposting technology needs the broad land. Because of the high cost of land in Korea, the land saving technology such as multistage must be needed. And present operation practices are mostly based on human power, mechanization and automation is needed. Also, present control practices are based on individual experience need the scientific base control system. 3. Considering situations of organic wastes management in Korea, the technical development and the practical improvement of Vermicomposting as the waste recycling will be needed.

• Korean Journal of Agricultural Science
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• v.46 no.4
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• pp.991-997
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• 2019

This study was conducted to investigate the laying period performance of two crossbred Korean native chicken (KNC) grand parent stock (GPS) layer during 20 to 40 weeks. A total of 351 20-week-old KNC GPS were allocated in a completely randomized design to give 4 birds per each cage. The chickens were fed commercial diets [i.e., week 20 - 32, crude protein (CP) 18.0% and metabolizable energy (ME) 2,850 kcal/kg; week 32 - 40, CP 17.0% and ME 2,800 kcal/kg)] and fresh water during the whole experiment period ad libitum basis. Body weight, age of sexual maturity, egg weight, hen-day egg production (HDP) and feed conversion ratio (FCR) were measured during the experiment period (week 20 - 40). The results show no significant difference in the Body weight, age of sexual maturity, egg weight, and hen-day egg production (HDP) except for egg weight. 1B had a higher egg weight on week 36 only. We expect that the reason why most factors showed no significant difference is the lack of nutrients caused by limited feeding which follows the standard feeding system for the grand-parent stock. These results provide basic information for laying data in 2-way crossbred Korean native chickens.

• Journal of Acupuncture Research
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• v.37 no.2
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• pp.110-117
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• 2020

Background: The aim of this pilot study was to assess the safety and dosing of scolopendrid pharmacopuncture (SPP). Methods: A total of 40 healthy Sprague-Dawley rats (males and 20 females 20) were selected following a 7-day inspection and acclimation period. SPP was administered via intramuscular injection, over a 2-week period using 3 doses including a high-dose [0.84 mg of scolopendrid per kg of body weight (BW)], a med-dose (0.42 mg/kg BW), and a low-dose (0.21 mg/kg BW). The control group was injected with sterile water into the muscles. Unusual changes caused by administration of the test substance were observed. Weight, feed intake, organ weight, and hematological examinations were compared among the groups. Using the SPSS statistical program, Levene's test was performed to evaluate the homogeneity of variances, and a one-way ANOVA test was subsequently performed to assess the significance between each test group. Results: During the experiment no animals died. Weight change, food consumption, organ weight, hematological test, and blood biochemical tests showed no significant differences in the treatment groups compared to controls. Conclusion: No toxicological changes related to the administration of test substances were observed. Therefore, the LD₅₀ (lethal-dose that kills 50%) of scolopendrid pharmacoupuncture in rats was greater than 0.84 mg/kg.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.31 no.1 s.256
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• pp.26-35
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• 2007

The vehicle of urban transit is a complex system that consists of various electric, electronic, and mechanical equipments, and the maintenance cost of this complex and large-scale system generally occupies sixty percent of the LCC (Life Cycle Cost). For reasonable establishing of maintenance strategies, safety security and cost limitation must be considered at the same time. The concept of system reliability has been introduced and optimized as the key of reasonable maintenance strategies. For optimization, three preceding studies were accomplished; standardizing a maintenance classification, constructing RBD (Reliability Block Diagram) of VVVF (Variable Voltage Variable Frequency) urban transit, and developing a web based reliability evaluation system. Historical maintenance data in terms of reliability index can be derived from the web based reliability evaluation system. In this paper, we propose applying inverse problem analysis method and hybrid neuro-genetic algorithm to system reliability optimization for using historical maintenance data in database of web based system. Feed-forward multi-layer neural networks trained by back propagation are used to find out the relationship between several component reliability (input) and system reliability (output) of structural system. The inverse problem can be formulated by using neural network. One of the neural network training algorithms, the back propagation algorithm, can attain stable and quick convergence during training process. Genetic algorithm is used to find the minimum square error.

• KSBB Journal
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• v.17 no.2
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• pp.176-181
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• 2002

Astaxanthin (3,3＇-dihydroxy-${\beta}$, ${\beta}$-carotene-4-4＇-dione), a natural pigment of pink to red color, is widely distributed in nature particularly in the skin layer of salmonoids and the crust of shrimp, lobster, etc. Recently, it was produced from the yeast culture of Phaffia rhodozyma. Because of its high thermal stability and antioxidant functionality, its applications can be extended into food, cosmetics, and pharmaceutical ingredient beyond the traditional feed additive. Because of its very high lipophilicity, astaxanthin has been extracted traditionally by strong organic solvents such as chloroform, petroleum ether, acetone, etc. In this study, we developed a surfactant-based solubillization system for astaxanthin, and used it to extract astaxanthin from disrupted yeast cells. Among Tween 20, Triton X-100 and SDS, Tween 20 was identified as the most suitable surfactant in terms of extraction capacity and safety. The ethylene oxide group of Tween 20 was identified as the most significant factor to increase the HLB value that determined the extraction capacity. The effects of micelle formation condition, such as the molar ratio of astaxanthin and Tween 20, pH, and ionic strength were also investigated. pH and ionic strength showed no significant effects. The optimal molar ratio between astaxanthin and Tween 20 was 1 : 12. Antioxidant activity of astaxanthin was higher than ${\beta}$-carotene and ${\alpha}$-tocopherol. Astaxanthin in the crude extract from the yeast cell was more resistant to air and/or light degradation than pure astaxanthin, probably because of the presence of other carotenoids and lipids.

• Applied Chemistry for Engineering
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• v.10 no.3
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• pp.467-476
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• 1999

This paper analyzed the behavior of fixed-bed catalytic reactor (FBCR) which synthesizing maleic anhydride(MA) from the selective oxidation of n-butane. The behavior of FBCR describing convection-diffusion-reaction mechanism is examined by using two-dimensional pseudohomogeneous plug-flow transient model, with the kinetics of Langmuir-Hinshelwood type. Prediction model is composed by optimum parameter estimation from temperature profile, yield and conversion of single FBCR on operating condition variations of Sharma's pilot-plant experiment. A double FBCR with same yield and conversion for single FBCR generated a $8.96^{\circ}C$ lower hot spot temperature than a single FBCR. We could predict parametric sensitivity according to the variation of possible operating condition (temperature, concentration, volumetric flow of feed reactant and coolant flow rate) of single and double FBCR. Double FBCR showed the behavior of more operating range than single FBCR. Double FBCR with nonuniform activities could assure safety operation condition for the possible variation of operating condition. Also, double FBCR had slightly higher than the single FBCR in conversion and yield.

• Journal of Korea Society of Industrial Information Systems
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• v.19 no.6
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• pp.15-24
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• 2014

The implementation of HACCP(Hazard Analysis and Critical Control Point) which is a systematic preventive approach to food safety is increasing in school feed or food manufacture. Thus, there are several automatic systems to assist HACCP management, however the most of existing systems are one of computer programs or correcting sensor data programs as ancillary means. Therefore, to be applied to efficiently automate HACCP system, the HACCP supporting computer system should be easy usability of the personnel involved in the HACCP operations and must be able to manage in real time the various HACCP data. In this paper, we develop a web-based HACCP automatic system operating freely available from any Internet computing environments. This system can be used as the management system of all the processes of HACCP and make possible to manage a broad range of operating information through the web server. So, the results from operation of the proposed automatic HACCP system can be consistently systematic.

• Journal of the Korean Dietetic Association
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• v.12 no.4
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• pp.404-410
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• 2006

This study was done to analyze the contents of food and nutrition information sites on the internet. In analysis, 276 web sites were used. Web sites from 3 internet search engines(Yahoo, Empas, Naver) were selected on the date of July 15th, 2004. The trained panels evaluated web sites' contents by the assessment tools using 3-point scale(2:strongly agree, 1:agree, 0:disagree). The contents classified by topics were functional foods(46.4%), cuisine and cooking(38.4%), food sanitation and safety(30.4%) and so on. Operators of web sites were individual(35.9%), company(30.4%) and public institution(33.7%). About 89.5% of web sites were operated for unspecified people. Contents of the web sites were well established especially in consistency in title and contents(1.6), scientific basis of explanations(1.2) and benefit of information(1.2) and so on while not well established in providing relevant sites(0.7), providing contact address and feed back mechanism(0.7) and so on. Web sites operated by public institutions are rated significantly higher than web sites operated by individual or company. In conclusion, in order to qualitatively improve food and nutrition information on the internet, continuing monitoring and evaluation are highly required and web sites operated by public institutions shall be developed further.

• Nuclear Engineering and Technology
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• v.47 no.1
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• pp.47-58
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• 2015

Four recycling scenarios involving pyroprocessing of spent fuel (SF) have been investigated for a 600-MWe transmutation sodium-cooled fast reactor (SFR), KALIMER. Performance evaluation was done with code system REBUS connected with TRANSX and TWODANT. Scenario Number 1 is the pyroprocessing of Canada deuterium uranium (CANDU) SF. Because the recycling of CANDU SF does not have any safety problems, the CANDU-Pyro-SFR system will be possible if the pyroprocessing capacity is large enough. Scenario Number 2 is a feasibility test of feed SF from a pressurized water reactor PWR. Thefsensitivity of cooling time before prior to pyro-processing was studied. As the cooling time sensitivity of cooling time before prior to pyro-processing was studied. As the cooling time increases, excess reactivity at the beginning of the equilibrium cycle (BOEC) decreases, thereby creating advantageous reactivity control and improving the transmutation performance of minor actinides. Scenario Number 3 is a case study for various levels of recovery factors of transuranic isotopes (TRUs). If long-lived fission products can be separated during pyroprocessing, the waste that is not recovered is classified as low- and intermediate-level waste, and it is sufficient to be disposed of in an underground site due to very low-heat-generation rate when the waste cooling time becomes >300 years at a TRU recovery factor of 99.9%. Scenario Number 4 is a case study for the recovery factor of rare earth (RE) isotopes. The RE isotope recovery factor should be lowered to ${\leq}20%$ in order to make sodium void reactivity less than <7$, which is the design limit of a metal fuel.

• International Journal of Industrial Entomology and Biomaterials
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• v.20 no.2
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• pp.75-77
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• 2010

Until now, the main treatment for impotence has been the vasodilator injection, penile implants and etc. Among many methods, most effective way is known to be the medical therapy. The oral drug for an impotence remedy has to be above all, effective to the erection, and second, safety when taking in long-term. However, so far the drug in such condition and sufficiency has not been discovered. Consequently, it is crucial to develop the new medicine, made of natural materials only, without any uncertainty of side effect. The silkworm is very difference in physiological chemical change according to growth stage. Therefore the functional effect shows a very big difference according to preparation method with a growth stage. This research carry out the experiment with the pupa powder immediately before the eclosion, eclosion adult, the pupa extract immediately before the eclosion, and the silkworm powder of 5 instar 3rd day. The result showed not a big chance in weight, feed and water intake quantity. But testosterone hormone secretion effects of the freeze drying powder of the pupa immediately before the eclosion was very high 7.31 ng/ml, compared to 2.37 ng/ml of non treatment and 2.67 ng/ml of alcohol extraction method. As this result, the freeze drying pupa powder of the pupa immediately before the eclosion was confirmed to promote the secretion of the testosterone hormone more than alcohol extraction method of existing.