• Transactions of the Korean Society of Mechanical Engineers A
• /
• v.23 no.11 s.170
• /
• pp.1896-1903
• /
• 1999

The basic requirements to improve the joints quality of tube-to-tubesheet for heat exchangers are to obtain high residual contact pressures between the tubes and the tubesheet as well as low residual stresses in the transition zone of the tubes. The residual contact pressures and residual stresses which govern the joint quality are influenced by parameters such as material properties, geometric dimension of tube and tubesheet and expansion pressures. There are two types of tube layout patterns, triangular and square, which are frequently used for heat exchangers. The purpose of the present work is to examine the superior tube layout patterns considering the joints quality by comparing numerical results from sensitivity analyses which were performed for both of tube layout patterns.

• Proceedings of the KSME Conference
• /
• 2003.11a
• /
• pp.1921-1926
• /
• 2003

Nano-imprint technology has been vigorously studied by many researchers for it is one of the most promising technologies for manufacturing the pattern with its critical dimension below 100nm. In the nano-imprint technology, nano patterns are transferred on a polymer film and the transferred patterns are used as an etch mask to define the designed patterns on a substrate or a metal layer. To this end, it is important to keep the residual thickness of the imprinted polymer film uniform. In this study, a novel measurement technique to measure the residual thickness of films is proposed based on nanoindentation theory. This technique has advantages of saving time and measuring the residual thickness of highly-localized portions in comparison with other techniques, but has limitation of requiring calibration process.

• Korean Journal of Environmental Agriculture
• /
• v.34 no.3
• /
• pp.223-229
• /
• 2015

BACKGROUND: It is important to understand residual patterns of pesticides applied on crops for ensuring their safety in agricultural products. However, there are few studies on the residual patterns of pesticides in minor crops, which are small in cultivation area. In this study, residual amounts of bifenthrin and chlorfenapyr sprayed on perilla leaf as a minor crop were investigated to know their residual patterns. METHODS AND RESULTS: Bifenthrin and chlorfenapyr were sprayed 2 or 3 times on perilla leaves at a week interval prior to harvest, and the perilla leaves were collected at 0, 1, 3, 5 and 7 days after the final application of pesticides. Recoveries for residual analysis of pesticides spiked on perilla leaves with concentrations of 0.1 and 0.5 mg/kg were 81.9-104.8%. The residual amounts of pesticides interpreted using first order kinetics model show that dissipation constants of bifenthrin and chlorfenapyr in perilla leaves were 0.0724-0.0535 and $0.0948-0.0821day^{-1}$, respectively. In addition, the dissipation half-lives in perilla leaves were 9.6-12.9 days for bifenthrin and 7.3-8.4 days for chlorfenapyr. When pre-harvest residue limits (PHRL) of bifenthrin and chlorfenapyr at 10 days before harvest calculated on the basis of the dissipation constants and maximum residue limits of the pesticides were calculated as 17.1 for bifenthrin and 15.9 mg/kg for chlorfenapyr. CONCLUSION: Therefore, the PHRL calculated using the time-dependant residual patterns of pesticides in perilla leaves and their regression analysis may be used as experimental evidences in order to ensure the safety of pesticides in perilla leaves before harvest.

• Korean Journal of Veterinary Research
• /
• v.36 no.3
• /
• pp.531-539
• /
• 1996

The lectin-binding patterns in the testis of the sexually matured Jindo dog were investigated to study the distribution of glycoconjugates in the seminiferous tubule under light and transmission electron microscopy. Positive reactions to Wheat germ agglutinin(WGA) and Dolichos biflorus agglutinin (DBA) were observed in the Sertoli cell and in the residual body of spermatid with a stronger reaction in the Sertoli cell to the lectins than in the residual body. Strong reactions to Soybean agglutinin(SBA) and Peanut agglutinin(PNA) were observed in the acrosome vesicles of the Golgi- and cap-phase spermatid, while a moderate reaction was observed in the acrosome-phase, maturation-phase spermatid and the residual body. The acrosome area of the spermatid reacted intensively to Griffonia simplicifolia agglutinin( GS-I) when the cell was in the acrosome-phase and maturation-phase, and the same reaction to the GS-I was observed in the residual body. However, the seminiferous tubule did not react to Ulex europeus agglutinin I(UEA-I). The gold-labelling of the Sertoli cells with DBA resulted in positive reactions of the Sertoli cell column and processes when observed under the electron microscopy, while the Golgi-, cap- and acrosome-phase spermatids reacted positively to SBA in the peripheral low-dense area of the acrosome vesicle of spermatid. Based on these results, we concluded that differences in the lectin-binding pattern of the seminiferous tubules were recognized in the Jindo dog compared to other animals.

• Proceedings of the Korean Society of Coastal and Ocean Engineers Conference
• /
• 1997.10a
• /
• pp.73-76
• /
• 1997

The purpose of this study is to find sedimentation patterns variation in Saemangeum coastal sea region. Water circulations are calculated diagnostically from the observed water temperature and salinity data and wind data and tidal residual current. Three dimensional movements of injected particles due In currents, turbulence and sinking velocity are tracked by the Euler-lagrange method. Calculated sedimentation patterns of riverine material are highly similar to the observed ones.

• International Journal of Air-Conditioning and Refrigeration
• /
• v.10 no.4
• /
• pp.177-183
• /
• 2002

A pulsed tracer gas technique is applied to measure the distributions of local mean age and local mean residual-life-time of air in a half-scale experimental chamber, The airflow patterns in the chamber are visualized by a Helium bubble generator for three different exhaust locations. A supply slot is located at the top of a right wall, and an exhaust slot is at either bottom-left (Case 1), bottom-right (Case 2), or top-left (Case 3) location. Results show that the distributions of local mean age and local mean residual-life-time are different from each other, but both of them are closely related to the airflow pattern in the space. Included are discussions on explaining the variations of overall room ventilation effectiveness depending upon airflow rates for three different supply-exhaust configurations.

• Journal of Advanced Navigation Technology
• /
• v.16 no.5
• /
• pp.801-809
• /
• 2012

Dispersion management (DM) is the typical technique compensating for the distorted signals due to interaction of group velocity dispersion (GVD) and optical nonlinear effects for transmitting wavelength division multiplexed (WDM) channel with the excellent performance. Optimal net residual dispersion (NRD) and effective launching power range of optical transmission links with random distribution and artificial distribution of single mode fiber (SMF) length and residual dispersion per span (RDPS) required to flexibly design of optical links in DM. It is confirmed that optimal net residual dispersion (NRD) are +10 ps/nm and -10 ps/nm controlled by precompensation and postcompensation, respectively, in both of the considered distribution patterns of SMF length and RDPS. And, in optimal NRD, system performance in optical links with the descending distribution of SMF length and the ascending distribution of RDPS among the artificial distribution patterns are more improved, consequently, effective launching power range is expanded by almost 2 dB than those in optical links with the uniform distribution.

• Journal of the Korean institute of surface engineering
• /
• v.42 no.5
• /
• pp.191-196
• /
• 2009

Nanocrystalline Cu thin films were electrodeposited from sulfate baths and investigated systematically the influences of $Cu^{2+}$ concentration and additives on current efficiency, residual stress, surface morphology, and XRD patterns of electrodeposited Cu film. Current efficiency was nearly 100% at from 0.2M to 1.0 M $Cu^{2+}$ concentration. but it was linearly increased with $Cu^{2+}$ concentration at less than 0.2M. The residual stress was observed in range of 7.9 to 18.4 MPa and tensile stress mode. Dendritic and powdered form was obtained at below 0.1 M. As increased with $Cu^{2+}$ concentration in solution, the main peak in the XRD pattern shifted (111) and (220) from (200). In the other hand, all about 100% current efficiency observed in all additive concentration systems, and residual stress observed in range of 20.4 to 26.3 MPa tensile stress. The condition 5(Ultra make-up - 10 ml/l, Ulta A - 0.5ml/l, Ultr B - 0.5 ml/l) was good surface morphology, and fcc(111) peak in XRD patterns increased with increasing additive concentration.

• Journal of Fashion Business
• /
• v.17 no.2
• /
• pp.179-196
• /
• 2013

This research is about the mechanical properties of knit pullover of Shaping and WholeGarment according to structured patterns and form of the armhole. For the study 12 samples are prepared under different conditions and through comparative analysis of each sample's armhole around armpit in basic properties, tensile strength & elongation and residual elongation after repeated extensions, the conclusion is as follows. As a result of comparing basic properties of structured pattern of Shaping and WholeGarment samples, in all structured patterns Shaping samples weighed more. According to the comparative analysis of tensile strength & elongation of Shaping and WholeGarment samples, Machi on both sides of WholeGarment samples showed the highest strength. By comparing outcome of residual elongation by structured pattern of Shaping and WholeGarment samples, both types were observed to have the residual elongation increase in the order of Plain

• Journal of the Korean Society for Marine Environment & Energy
• /
• v.4 no.1
• /
• pp.14-23
• /
• 2001

The characteristics of tidal circulation with Hyungsan River discharges in Youngil Bay by the numerical experiments is elucidated. For the simulation of tidal residual currents related to inflow by the river discharges in Youngil Bay located in the southeastern part of Korean Peninsula, the two-dimensional numerical experiment is peformed. The tidal elevation boundary conditions of the 4 main tidal harmonic constituents (M₂, S₂, K₁ and O₁) on the open boundary and river discharges at the river boundary are considered. The computed results obtained from numerical experiment showed good agreements with the field observation ones. The residual currents generally flow toward the inner bay through the western (Dalman-Gap) and central areas of the bay, and then the currents go toward the outer bay along the eastern shore (Changgi-Gap) of the bay with anti-clockwise circulation. Especially, in the numerical experiment without Hyungsan River discharges, these flow patterns are disappeared. Based on the results, it showed that the Hyungsan River discharges play the dominant role in the patterns of tidal residual currents. This flow pattern of tidal residual currents are important mechanism of water quality, material transport in Youngil Bay.