• International Journal of Fluid Machinery and Systems
• /
• 제9권4호
• /
• pp.370-381
• /
• 2016

As a single-channel pump is used for wastewater treatment, this particular pump type can prevent performance reduction or damage caused by foreign substances. However, the design methods for single-channel pumps are different and more difficult than those for general pumps. In this study, a design optimization method to improve the hydrodynamic performance of a single-channel pump impeller is implemented. Numerical analysis was carried out by solving three-dimensional steady-state incompressible Reynolds-averaged Navier-Stokes equations using the shear stress transport turbulence model. As a state-of-the-art impeller design method, two design variables related to controlling the internal cross-sectional flow area of a single-channel pump impeller were selected for optimization. Efficiency was used as the objective function and was numerically assessed at twelve design points selected by Latin hypercube sampling in the design space. An optimization process based on a radial basis neural network model was conducted systematically, and the performance of the optimum model was finally evaluated through an experimental test. Consequently, the optimum model showed improved performance compared with the base model, and the unstable flow components previously observed in the base model were suppressed remarkably well.

• 대한소아치과학회지
• /
• 제38권4호
• /
• pp.427-434
• /
• 2011

중심교합위의 상태에서 편측 혹은 양측으로 상악 구치부의 치아가 하악 구치부의 협측으로 위치한 경우를 scissors bite라고 한다. 이는 상악의 폭경이 크거나 하악의 폭경이 좁은 경우 발생한다. Scissors bite의 경우 방치하게 되면 하악의 성장이 방해받게 되고 그 결과, 악궁 폭경의 부조화가 심해져 저작 장애를 일으킬 수 있으므로 조기 차단 교정이 반드시 필요하다. 실제 임상에서는 여러 치아의 scissors bite보다 최후방 구치 혹은 그 외 하나의 구치만의 single tooth scissors bite(STSB)을 보이는 경우가 많다. 이러한 STSB의 경우도 방치하게 되면 저작력으로 인하여 구치의 각도가 더욱 악화되므로 즉각적인 치료가 필요하다. 본 증례에서는 STSB를 보이는 7세, 14세, 12세, 16세의 환자에게 각각 criss-cross elastic, 고정성 장치, 가철성 장치, miniscrew를 사용하여 치료한 증례를 보고하였다. 각 환자의 증례에 적합한 장치를 잘 선택하여 사용한다면 치아를 정출시키는 등의 부작용을 야기하지 않고 양호한 결과를 얻을 수 있을 것이다.

• 한국근적외분광분석학회:학술대회논문집
• /
• 한국근적외분광분석학회 2001년도 NIR-2001
• /
• pp.1521-1521
• /
• 2001

The objective of the research being presented was to construct and calibrate a spectrometer for the analysis of single kernels of corn. In light of the difficulties associated with capturing the spatial variability in composition of corn kernels by single-beam spectrometry, a hyperspectral imaging spectrometer was constructed with the intention that it would be used to analyze single kernels of corn for the prediction of moisture and oil content. The spectrometer operated in the range of 750- 1090 nanometers. After evaluating four methods of standardizing the output from the spectrometer, calibrations were made to predict whole-kernel moisture and oil content from the hyperspectral image data. A genetic algorithm was employed to reduce the number of wavelengths imaged and to optimize the calibrations. The final standard errors of prediction during cross-validation (SEPCV) were 1.22% and 1.25% for moisture and oil content, respectively. It was determined, by analysis of variance, that the accuracy and precision of single-kernel corn analysis by hyperspectral imaging is superior to the single kernel reference chemistry method (as tested).

• The Journal of Korean Physical Therapy
• /
• 제32권3호
• /
• pp.163-167
• /
• 2020

Purpose: Unilateral strength training effects on contralateral sides have been demonstrated in previous studies for lower extremity exercise, upper extremity exercise, and unilateral surface electrical stimulation. This study was performed to investigate the effects of unilateral ankle training on muscle strength and the balance of contralateral lower extremity in healthy adults. Methods: Thirty healthy subjects were randomized equally to a training or a control group. Those in the training group received unilateral ankle isokinetic strengthening training of the dominant leg (right side) for 4 weeks. Contralateral single-limb balance, including Anterio-Posterior Stability Index (APSI), Medio-Lateral Stability Index (MLSI) and Overall Stability Index (OSI), was assessed before and after intervention. Results: Comparison of pre- and post-test data revealed significant improvements in ipsi- and contralateral ankle strengths, and significant improvement in contralateral single limb balance. Conclusion: These results have practical implications because they demonstrate that unilateral ankle isokinetic exercise improves ankle muscle strength and balance ability of contralateral lower extremity.

• Asian-Australasian Journal of Animal Sciences
• /
• 제2권2호
• /
• pp.103-114
• /
• 1989

Reciprocal crosses were conducted between three strains of Taiwan Country chickens, developed in the National Chung-Hsing University, and two strains of Single Comb White Leghorns, developed in the Taiwan Livestock Research Institute. Traits studied were growing performances, laying performances, egg quality traits and traits concerning disease resistance, including resistance to Marek's disease virus and immune responses to Newcastle disease virus vaccine and to sheep red blood cell. Results indicated that laying performances of Taiwan country chickens were much inferior to White Leghorns, but they matured earlier, their eggs had better shell strength and larger proportion of yolk, and their general disease resistance was much better than White Leghorns. Heterosis were found in laying performances and egg quality traits. The heterosis in laying traits was so large that the hybrid laid as many eggs and as large eggs as did pure strains of White Leghorns. Strategies on the improvement of native chickens and the utilization of genetic merits of native chickens were also discussed.

• 한국전자파학회논문지
• /
• 제7권2호
• /
• pp.167-177
• /
• 1996

임의의 이중 ridge 구형도파관의 단면에서 모우드 해석을 적용하여 차단주파수들을 계산 하였다. 그리고 주파수 6~8GHz에서 $TE_{10}$ 모우드에 대한 특성 임피던스를 구하였다. 선형으로 taper된 구형도파관 양단이 단일 및 이중 ridge구형 단면으로 구성되어 있을 경우 $TE_{10}$ 모우드에 대한 등가 비균일 전송선을 수치계산으로 풀었다. 단일 ridge도파관이 있는 종단명에서 들여다 본 입력 임피던스는 광대역에서도 거의 일정한 값을 가짐을 보였다.

• 한국복합재료학회:학술대회논문집
• /
• 한국복합재료학회 2005년도 추계학술발표대회 논문집
• /
• pp.198-201
• /
• 2005

This study investigates the difference between single-cell and multi-cell cross-sections of thin-walled beams. The variationally and asymptotically consistent theory is used in order to model the two-cell thin- walled beam. The theory is based on an asymptotical analysis of two-dimensional shell energy. In addition, the method allows for the development of closed-form expressions for the displacement, stress field and beam stiffness coefficients. The numerical results show the difference between the cross-sectional stiffness of single-cell and that of multi-cell.

• International Journal of Industrial Entomology and Biomaterials
• /
• 제7권2호
• /
• pp.191-195
• /
• 2003

The impact of antibiotic (Norfloxacin) administration ,at different concentration (50 ppm and 100 ppm) on commercial characters of bivoltine $({CSR_2}{\times}{CR_4})$ and the cross breed race $({BL_67}{\times}{CSR_101})$ was studied. The result indicated that antibiotic administration with different concentrations significantly improved the rearing and cocoon parameters like larval duration, larval weight, growth index, single cocoon weight, single shell weight and shell ratio. The post cocoon parameters like average filament length, non-breakable filament length, raw silk percentage, raw silk recovery percentage, denier, reelability and neatness were recorded significantly higher in antibiotic treated batches. The better performances of these parameters were recorded with the increase of antibiotic concentration.

• 대한기계학회:학술대회논문집
• /
• 대한기계학회 2003년도 추계학술대회
• /
• pp.61-66
• /
• 2003

Fouling is very serious problem in heat exchanger because it rapidly deteriorates the performance of heat exchanger. Cross-flow heat exchanger with vortex generators is developed, which enhance heat transfer and reduce fouling. In the present heat exchanger, shell and baffle are removed from the conventional shell-and-tube heat exchanger. The naphthalene sublimation technique is employed to measure the local heat transfer coefficients. The experiments are performed for single circular tube, staggered array tube bank and in-line array tube bank with and without vortex generators. Local and average Nusselt numbers of single tube and tube bank with vortex generator are investigated and compared to those of without vortex generator.

• 한국지구물리탐사학회:학술대회논문집
• /
• 한국지구물리탐사학회 2007년도 공동학술대회 논문집
• /
• pp.87-92
• /
• 2007

This work describes the installation and preliminary measurements of an electrical resistivity tomography (ERT) system to monitor the injection of recycled water into a confined aquifer in the area of Sindos (Thessaloniki N. Greece). The aim is to provide, through time-lapse ERT measurements and processing, geoelectrical images of rather increased volumetric sampling around and between the holes and to obtain improved understanding of the flow and transport of the injected water. The details about the general setting, the construction and installation of the ERT cables into the boreholes are explained in full. Preliminary measurements involving single and cross-hole ERT measurements were obtained and processed with a 2D inversion algorithm to produce images of the subsurface. Results depict a very good correlation between ERT images and the lithology and resistivity logs; an indication of the reliability of the approach.