• The Journal of the Acoustical Society of Korea
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• v.23 no.4
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• pp.316-323
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• 2004

Recent trend of installation of highly efficient and high Power engine in vehicles has increased complaints about exterior noise being made while travelling. To examine the sources of outer noise of vehicles controlled by regulations. using lead wrapping method. Pass-by noise tests have been conducted as opening each defined source one by one. The sources of outer noise have been found and the rate of noise contribution has been produced. The results of the tests have been applied to put noise-reducing objects in the order, and counter plans effective to reduce noise have been devised.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 1999.08a
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• pp.320-326
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• 1999

In the present investigation, recrystallization occurring during hot rolling of thick steel plate was predicted. The thermo-mechanical history of a material point was traced by the finite element method and the recrystallization was predicted by the Sellars equations. The investigation was performed for 4 different cases; two different pass schedules in conventional rolling and two different pass schedules in controller rolling. Variations of temperature, strain, strain rate and grain size were compared with each other. It was found out that the difference of grain size through thickness was more distinctive in the cases of controller rolling.

• Proceedings of the Korean Society for Technology of Plasticity Conference
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• 2004.05a
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• pp.27-30
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• 2004

Clad wire , which has the advantages of the high strength of a steel core and the electro-conductivity, corrosion resistance of a copper layer, is widely being used the telecommunications, electric-electronic and military technology industries, among others. It is important to obtain uniform coated rate when producing clad wires. Clad wire drawing process can be influenced on damage and coated rate of core and sleeve by process variables as semi-die angle and reduction in area. Therefore, in this study, the finite-element results established in previous study is used to analyze the effect of the various forming parameters, which included the semi-die angle, reduction in area etc. The coated rate will be predicted with observation copper coated rate variation according to total reduction in area and the optimal pass schedule will be set up through proper reduction in area and semi-die angle variation.

• The Journal of the Acoustical Society of Korea
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• v.19 no.1
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• pp.89-96
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• 2000

ABR service is defined by ATM Forum and ITU for the efficient use of link bandwidth, and 2-pass service policing is proposed for this service. 2-pass service policing is effective by the real-time measurement of the used bandwidth, and this scheme obtains multiplexing gam and control efficiently ABR traffic as dynamically allocating rate by residual bandwidth information. In this study, we propose the real-time bandwidth prediction scheme for ABR traffic control, as using dynamic rate allocation by available bandwidth information. This study can obtain the simple hardware structure by means of as predicting available bandwidth by the total link bandwidth and the sum of transmission rate on the backlogged state connections.

• Proceedings of the SAREK Conference
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• 2006.06a
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• pp.737-742
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• 2006

This paper numerically investigates to evaluate the performance according to the number of passes and the inlet/outlet diameter in a multi-pass multi-branch heat exchanger. A JF factor is used as an evaluation characteristic value to consider the heat transfer rate and the pressure drop simultaneously. It estimates the performance according to the number of passes and the inlet diameter of the reference heat exchanger. When the ratio of the inlet diameter to the header height is about 0.5, the optimum number of passes is selected along with the inlet diameter.

• Journal of Mechanical Science and Technology
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• v.18 no.1
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• pp.114-121
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• 2004

In order to investigate the corrosion fatigue characteristics in the weld of multi-pass welded A 106 Gr B steel pipe, corrosion fatigue tests were performed under the various stress ratios and 3.5 wt% NaCl solution at room temperature. The corrosion fatigue characteristic curves were represented using crack closure concept. The obtained results are as follows : when the load frequency is 1.0 Hz, the crack opening point is transited in the region of $K_{max}$=20∼32 MPaㆍ $m^{1}$2/. In the low stress intensity factor range, the crack opening point is higher than that in air. However, in the high stress intensity factor range, it is lower than that in air. In the cases of 0.1 Hz and 0.01 Hz, the crack opening point gradually decreases to $K_{min}$ with $K_{max}$ increase.rease.

• YAKHAK HOEJI
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• v.39 no.4
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• pp.411-416
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• 1995

The single-pass perfusion experiments were performed in anesthetized rats to investigate the effects of perfusates and their osmolality on the water transport and to determine the correlation between the extent of water transport and the volume change of perfusate. Phenol red was used as a nonabsorbable marker. In normal rats, when perfused at a flow rate of 0.5 ml/min, 2-(N-rnorpholino) ethanesulfonic acid (MES) and S$\phi$rensen's phosphate buffers showed minimal net water transport as 0.125 and 0.173 %/cm of intestinal length, respectively. Hypotonic perfusate of 200 mOsm/kg of water and hypertonic perfusate of 400 mOsm/kg of water generated significant water transport compared with isotonic perfusate of 300 mOsm/kg of water. There was a linear correlation between the extent of water transport and the volume change of perfusate, suggesting that the volume change can be used as a measure of water transport.

• ETRI Journal
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• v.46 no.1
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• pp.106-117
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• 2024

Large language models (LLMs) have revolutionized various applications in natural language processing and exhibited proficiency in generating programming code. We propose a framework for evaluating the code generation ability of LLMs and introduce a new metric, pass-ratio@n, which captures the granularity of accuracy according to the pass rate of test cases. The framework is intended to be fully automatic to handle the repetitive work involved in generating prompts, conducting inferences, and executing the generated codes. A preliminary evaluation focusing on the prompt detail, problem publication date, and difficulty level demonstrates the successful integration of our framework with the LeetCode coding platform and highlights the applicability of the pass-ratio@n metric.

• Membrane and Water Treatment
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• v.2 no.2
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• pp.75-89
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• 2011

The predicting equations for mass transfer rate in cross-flow rectangular dialyzers with double flow and recycle, have been derived by mass balances. The recycling operation has two conflicting effects. One is the desirable effect of the increase in fluid velocity, resulting in an increased mass transfer coefficient. The other is the undesirable effect of the reduction in concentration difference due to remixing, resulting in decreased mass-transfer driving force. In contrast a single-pass device without recycling, considerable improvement in mass transfer is achieved if the cross-flow rectangular dialyzer of same size is operated with double pass and external recycling. It is concluded that recycle can enhance mass transfer, especially for larger reflux ratio.

• Current Optics and Photonics
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• v.5 no.2
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• pp.180-185
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• 2021

A femtosecond-laser inscribed Yb:YAG surface channel waveguide (WG) laser with single-walled carbon nanotubes deposited on the top surface of the WG was passively Q-switched by evanescent field interaction. Q-switched operation of the 14-mm-long compact Yb:YAG WG laser was achieved near 1031 nm with two different pumping schemes (single- and double-pass pumping) with an output coupling transmission of 91%. The Q-switched pulse characteristics depending on the absorbed pump power were investigated for both pumping geometries and analyzed in detail based on theoretical modeling. The best performances (energy/pulse duration) for each configuration were 204.4 nJ/75 ns at a repetition rate of 1.87 MHz, and 201.1 nJ/81 ns at 1.75 MHz for single- and double-pass pumping, respectively.