• Applied Chemistry for Engineering
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• v.19 no.5
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• pp.568-573
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• 2008

Kinetic tests on pyrolysis of waste fishing net [WFN; nylon-6], waste ship lubricating oil [WSLO] and their mixture were carried out by thermogravimetric analysis (TGA) with heating rate of 0.5, 1.0, and $2.0^{\circ}C/min$. Pyrolysis of waste fishing net started at $300^{\circ}C$, and the main region of decomposition temperature was between 360 and $440^{\circ}C$ at each heating rate. Decomposition temperature of the mixture of WFN and WSLO was lower than that of WFN and WSLO, and the shape of thermogravimetic graph of mixture was different as well. The corresponding kinetic parameters including activation energy and pre-exponential factor were determined by differential method over the degree of conversions. The values of activation energies for the mixture of WFN and WSLO were between 98 and 427 kJ/mol as the conversion increased from 5% to 95%. Tubing reactor was used to analysis of pyrolyzed oil at $440^{\circ}C$ for 80 min. The selectivity of specific hydrocarbons was not detected and the carbon number distribution of the pyrolyzed oil was below $C_{22}$.

• Archives of Reconstructive Microsurgery
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• v.8 no.2
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• pp.154-162
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• 1999

The laryngopharyngectomy for tumor ablation is the most common indication for pharyngoesophageal reconstruction in our country. Most of these cases are advanced laryngeal cancer that has spread beyond the larynx, pharynx and cervical esophagus. Such patients are obviously unable to breathe, swallow, or speak in the normal manner. The ideal reconstruction would restore normal anatomy, permitting patients to breathe and swallow without aspiration, and would not require a permanent tracheostomy. Reconstruction of the pharyngoesophageal defect traditionally been carried out with tubed local random flap, deltopectoral or musculocutaneous flap. Another approach is the pedicled enteric flap. But microsurgical reconstruction of the pharyngoesophagus, using either the free jejunal or the tubed radial forearm flap, have now become the preferred technique. Among them, we used jejunal free flap in 39 cases, tubed radial forearm free flap in 5 cases, patched radial forearm free flap in 2 cases and pectoralis major myocutaneous island flap in 2 cases from December 1990 to Febrary 1999. In this paper we illustrated that both forearm and jejunal free flap is a usful alternative in reconstruction of hypopharynx and cervical esophagus.

• Korean Journal of Food Science and Technology
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• v.35 no.5
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• pp.797-802
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• 2003

Structured lipids (SL) were synthesized by esterification of corn oil and conjugated linoleic acid (CLA) in a continuous packed-bed column reactor. The effects of flow rate, reaction temperature, and substrate molar ratios were studied. The reaction was catalyzed by TL IM (immobilized lipase from Thermomyces lanuginosa). Results of triacylglycerol (TAG) analysis by GC showed that the incorporated CLA isomers were mainly cis9, trans11- and trans 10, cis12-CLA. Slower flow rates yielded higher incorporation, and maximum incorporation of CLA was obtained with a molar ratio of 1:3 (corn oil: CLA) at a temperature of $55^{\circ}C$. The obtained SLs had iodine values ranging from 120 to 128. The SLs were composed of TAG $(98{\sim}99%)$, 1,2- and 1,3-diacylglycerol ($0.7{\sim}1.3%$), and a small amount of monoacylglycerol.

• Fire Science and Engineering
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• v.30 no.5
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• pp.67-73
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• 2016

This paper examined the structure, fire resistance of brass fittings type CSST employed in gas appliances and the reliability verification. Brass fittings of type CSST consisted of cladding, tubing, nut, clamp ring, socket, and ball valve. The applicable JIA standard regulates the maximum working pressure to be 4.2 kPa, which is the highest pressure of the relevant standards and the KS D 3625 stipulates the maximum pressure to be 3.24 kPa. With a normal product, the average resistance within the confidence interval was found to be $7.36m{\Omega}$. The average resistance within the confidence interval was $6.67m{\Omega}$ after the fire resistance tests. The analysis indicated that the AD was 1.584 and the standard deviation was 0.3972 with respect of a normal product. Compared to the normal product, however, the damaged product after the fire resistance test showed better features, such as an AD of 1.145 and a standard deviation of 0.2467. Moreover, the average resistance of the normal product was $7.359m{\Omega}$ and the standard deviation in histogram analysis was 0.3972. The average resistance of the damaged product after the fire resistance test in the histogram was $6.67m{\Omega}$ and the standard deviation was 0.2467.

• The Journal of Korean Medicine
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• v.31 no.3
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• pp.17-27
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• 2010

Objectives: Cocaine has been well known as a representative drug of abuse for its strong reinforcing effect linked to the mesolimbic reward system including dopamine, and such reinforcement leads to the addiction. Acupuncture has been used widely in eastern Asia for the treatment of various diseases including mental disorders and psychiatric problems, and is gathering more interest as one of the complementary and alternative medicines in western countries. In a previous study, we demonstrated that acupuncture at HT7 could affect dopamine release in the mesolimbic system of rats sensitized to alcohol and morphine. This study was designed to investigate whether acupuncture at HT7 could attenuate cocaine intake or not. Material & Methods: Male Sprague-Dawley rats weighing 270-300 g at the start of experiment were trained to self-administer food pellets under a fixed ratio 1 schedule. After the success of acquisition of 100 pellets within 3 h for 3 consecutive days, animals were subjected to surgery whereby Silastic tubing was implanted into right jugular vein and secured with mesh under the anesthetization using pentobarbital injection (50 mg/kg, i.p.). Following recovery, rats were trained to self-administer cocaine (0.25 mg/kg) in daily 2 h sessions under fixed ratio 1 schedule over 10 days. Each treatment was performed on the next day of each establishment of baseline. Results: Results show that acupuncture at HT7, but not at control points, reduced cocaine intake significantly. Acupuncture at HT7 decreased selectively active lever response from $63.15{\pm}3.35$ to $51.46{\pm}3.99$ corresponding $82.12{\pm}5.31%$ compared to basal level. Also, it was demonstrated that the effect of acupuncture was mainly occurred at the half period. Nevertheless, acupuncture at HT7 did not influence the food taking behavior. Conclusions: From the results of this study, it may be suggested that acupuncture at HT7, at least in part, could contribute to the treatment of cocaine abuse.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.17 no.5
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• pp.368-372
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• 1984

This paper deals with a rapid method for determination of ATP and its related compounds in fish and shellfish products using high performance liquid chromatography(HPLC). The HPLC used is a HPLC/ALC-224 equiped with UV-spectrophotometer (254 nm) as detector and integrator (Yanagimoto system-1000). The column used is a stainless steel tubing ($30.0\;cm{\times}3.9\;mm\;i.d.$) packed with ${\mu}-Bon-dapak\;C_{18}$. A mixture of $1\%$ triethylamine-phosphoric acid(pH6.5) was used as an eluent and the flow rate of the eluent was controlled at 2 ml/min. For the separation of ATP and its related compounds, a standard mixture of ATP, ADP, AMP, IMP, inosine and hypoxanthine was subjected to HPLC under the above mentioned conditions. Six peaks were obtained with retention times within 20 min, and elution order were hypoxanthine, IMP, inosine, AMP, ADP and ATP. But 5'-IMP and 5'-GMP fractions were not separated by this method. In generally, IMP content in boiled-dried fish and shellfish products purchased from the market was comparatively higher than that of other nucleotides. Especially, boiled-dried big eye herring marked higher value in IMP content than other boiled-dried ones. Hypoxanthine and inosine were major components of ATP-related compounds in dried products and seasoned-dried ones. And IMP content in seasoned-dried products was higher than that of dried ones. This fact is suggested that a part of IMP in seasoned-dried ones was derived from flavoring matter (MSG, 5'-IMP and 5'-GMP) which is added during the seasoning treatment.

• 월간산업보건
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• s.5
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• pp.4-15
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• 1988

In order to proffer the fundamental data for the better working environment and the effective establishment of hearing conservation program on workers exposed to industrial noise, author assessed noise levels on the 42 noisy processes among 84 manufactures of 9 industries and measured noise gearing loss by the type of industries on 3,104 workers at these noisy processes from March, 1986 to Februry, 1987. The results were summarized as follows: 1. The averge of A-weight sound level of 23 processes(54.8%) and the avergae of sound level at each octave band of 14 processes(33.3%) exceeded the permissible exposure limits in 8 hours per day. 2. The noise level was the highest in process of cocking of ship building(109.1dBA), and followed by plating of steel rolling(104.3dBA), rivet of manufacture of motor vehicles(102.5dBA), shot of ship building(98.5dBA), aciding(95.7BA) and steel tubing(95.0dBA) of steel rolling, weaving of textiles(95.0dBA). 3. The permissible exposure time for the average of sound level at each octave band was only 30 minutes in the process of cocking of ship building, plating of steel rolling and rivet of manufacture of motor vehicles. 4. As a result of audiometric examination in 3,104 workers, the rate of hearing loss over 50dB at 4,000Hz was 7.3%(227 workers) and the rate of hearing loss over 41dB at 60average method was 2.9%(89 workers). 5. The prevalence of occupational hearing loss in ship building and manufacture of motor vehicle was 5.2% and it was the highest among prevalence of these 9 industries. 6. As a result of this suvery, the noise control and gearing conservation program were required especially in the industry of ship building and manufacture of motor vehicle.

• Journal of Wetlands Research
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• v.8 no.3
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• pp.79-89
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• 2006

The survival rate and tube number of Monocorophium uenoi, one of the dominant species in Lake Sihwa, was investigated under laboratory condition with salinity gradients (1, 5, 10, 15, 20, 25, 30, 35, 40‰). Another laboratory experiments were conducted to investigate the survival rate of Monocorophium uenoi in sulphide-rich sediment with oxic overlying water, and the effect of amphipod bioturbation on sulphide and oxygen profiles. The survival rate and tube-forming number of the amphipod were high in salinity range of 20 to 30‰. The amphipod survival rate was also high in sulphidic sediment when the water column was oxic. The amphipod bioturbation affected the oxygen and sulphide content in the sediment; oxygen conditions in the upper sediment layers were improved, and simultaneously the concentrations of sulphide were reduced. And their depth was clearly dependent on amphipod density. In Lake Sihwa, previously anoxic bottoms with sulphidic sediment during summer turn oxic with pycnocline disappearance during autumn. Amphipods seem to have the capability to quickly invade such areas, and their tubing of the sediment may play an important role in preparing the sediment for further recolonisation of other macrobenthos.

• Journal of the Korean Society for Nondestructive Testing
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• v.28 no.4
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• pp.339-345
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• 2008

The heat exchanger tube in nuclear power plants is mainly fabricated from nonferromagnetic material such as a copper, titanium, and inconel alloy, but the moisture separator & reheater tube in the turbine system is fabricated from ferromagnetic material such as a carbon steel or ferrite stainless steel which has a good mechanical properties in harsh environments of high pressure and temperature. Especially, the moisture separator & reheater tubes, which use steam as a heat transfer media, typically employ a tubing with integral fins to furnish higher heat transfer rates. The ferromagnetic tube typically shows superior properties in high pressure and temperature environments than a nonferromagnetic material, but can make a trouble during the normal operation of power plants because the ferrous tube has service-induced damage forms including a steam cutting, erosion, mechanical wear, stress corrosion cracking, etc. Therefore, nondestructive examination is periodically performed to evaluate the tube integrity. Now, the remote field testing(RFT) technique is one of the solution for examination of ferromagnetic tube because the conventional eddy current technique typically can not be applied to ferromagnetic tube such as a ferrite stainless steel due to the high electrical permeability of ferrous tube. In this study, we have designed RFT probes, calibration standards, artificial flaw specimen, and probe pusher-puller necessary for field application, and have successfully carry out RFT examination of the moisture separator & reheater tube of nuclear power plants.

• Journal of Aerospace System Engineering
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• v.11 no.4
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• pp.48-53
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• 2017

Liquid rocket engines (LREs) are very complex systems that include combustion chambers, turbopumps, gas generators, ducts and tubes, valves and etc. Most components of the LREs require higher than or equal to level 6 IT (ISO Tolerance). The components along with pipe line and/or tubing must dispose not to interfere each other. In addition, effectiveness of maintenance and service after assembling should be considered when the allocation of the components are determined. Especially at the stage of the development, tolerance accumulations or unpredictable errors may result in misalignment and/or mismatches at interfaces of the parts. Namely, it is the engine assembling process that many inherent risks are realized and crises or incidents occur. Therefore, a rapid reaction system should be prepared. In this research, 7 tonf class liquid rocket assembling process was studied and actual building steps were introduced.