• Membrane Journal
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• v.12 no.2
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• pp.67-74
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• 2002

Submerged membrane bioreactor(SMBR) and reverse osmosis(R/O) systems treated dye wastewater for reusing of industrial water. The permeate fluxes of SMBR at 20-25 cmHg of lab. test and field test were 10 LMH($1/m^2$.hr) all test. Removal efficiencies of CODcr, $COD_{Mn}$ and T-N were 93%, 90% and 60% in the SMBR, respectively The advanced treatment of combined process(SMBR+R/0) was accomplished for increasing the removal efficiency of non-biodegradable materials and T-N. Therefore, the removal efficiency of T-N obtained in 80% above, then nitrogen concentration was under 15 mg/L. The combined process(SMBR+R/0) was suitable to reuse of the dye wastewater.

• Smart Structures and Systems
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• v.24 no.4
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• pp.491-506
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• 2019

Literature regarding concrete walls reinforced by super elastic shape memory alloy (SMA) bars is rather limited. The seismic behavior of a system concurrently including a distinct steel reinforced concrete (RC) wall, as well as another wall reinforced by super elastic SMA at the first story, and steel rebar at upper stories, would be an interesting matter. In this paper, the seismic response of such a COMBINED system is compared to a conventional system with steel RC concrete walls (STEEL-Rein.) and also to a wall system with SMA rebar at the first story and steel rebar at other stories ( SMA-Rein.). Nonlinear time history analysis at maximum considered earthquake (MCE) and design bases earthquake (DBE) levels is conducted and the main responses like maximum inter-story drift ratio and residual inter-story drift ratio are investigated. Furthermore, incremental dynamic analysis is used to accomplish probabilistic seismic studies by creating fragility curves. Results demonstrated that the SMA-Rein. system, subjected to DBE and MCE ground motions, has almost zero and 0.27% residual maximum inter-story drifts, while the values for the COMBINED system are 0.25% and 0.51%. Furthermore, fragility curves show that using SMA rebar at the base of all walls causes a larger probability of exceedance 3% inter-story drift limit state compared to the COMBINED system. Static push over analysis demonstrated that the strength of the COMBINED model is almost 0.35% larger than that of the two other models, and its general post-yielding stiffness is also approximately twice the corresponding stiffness of the two other models.

• Elastomers and Composites
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• v.49 no.2
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• pp.160-166
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• 2014

The formulation of six basecoats was designed using aluminium pastes for the per-painted system in the automotive. The aluminium pastes contain pancake type metallic pigment, #501, #801, #601 and cornflake type metallic pigment, #750, #770, #790. The relative cure density of the basecoat increased in order of #501, #801, #601, #750, #770, #790. T-bending, impact resistance, and taping adhesion showed increment with increasing cure density. In the appearance( combined factor) test on cornflake type pigment, The basecoat including the smallest particle size pigment, #790 resulted in the best combined factor compared to other two systems(#750, #770).

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.17 no.6
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• pp.560-568
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• 2005

The cost accounting of electricity and heat produced from an energy system is important in evaluating the economical efficiency and deciding the reasonable sale price. The OECOPC method, suggested by the author, was applied to a 650 MW combined cycle cogeneration system having 4 operating modes, and each unit cost of electricity and heat products was calculated. In case that a fuel cost is ${\\}400/kg$ and there are no direct and indirect cost, they were calculated as follows; electricity cost of ${\\}23,700/GJ$ at gas-turbine mode, electricity cost of ${\\}15,890/GJ$ at combined cycle mode, electricity cost of ${\\}14,146/GJ$ and heat cost of ${\\}6,466/GJ$ at cogeneration mode, and electricity cost of ${\\}14,387/GJ$ and heat cost of ${\\}4,421/GJ$ at combined cycle cogeneration mode. Further, these unit costs are applied to account benefit on this system. Since the suggested OECOPC method can be applied to any energy system, it is expected to contribute to cost accounting of various energy systems.

• Journal of the Earthquake Engineering Society of Korea
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• v.27 no.2
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• pp.91-99
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• 2023

Structural vibration induced by earthquake hazards is one of the most significant concerns in structure performance-based design. Structural hazards evoked from seismic events must be properly identified to make buildings resilient enough to withstand extreme earthquake loadings. To investigate the effects of combined earthquake-resistant systems, shear walls and five types of dampers are incorporated in nineteen structural models by altering their arrangements. All the building models were developed as per ACI 318-14 and ASCE 7-16. Seismic fragility curves were developed from the incremental dynamic analyses (IDA) performed by using seven sets of ground motions, and eventually, by following FEMA P695 provisions, the collapse margin ratio (CMR) was computed from the collapse curves. It is evident from the results that the seismic performance of the proposed combined shear wall-damper system is significantly better than the models equipped with shear walls only. The scrutinized dual seismic resisting system is expected to be applied practically to ensure a multi-level shield for tall structures in high seismic risk zones.

• Journal of the Korean Data and Information Science Society
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• v.23 no.4
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• pp.787-796
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• 2012

The aim of this study is to closely examine the changes in their metabolic syndrome index and autonomic nerve systems after the 16-weeks's combined exercise program is carried out on low-level physical strength group (PAPS 4-5 level students). They were divided into two groups; exercise training group (15) and control group (15). This program consisted of five-times-a-week's warm-ups, main activities and warm-downs and it takes 50 minutes per trial. Through SPSS 19.0, all averages and standard deviations of dependent variables were calculated. We first performed Shapiro-Wilk's normality test of the variables. Before verifying the effect of combined exercise program, we tested the equality of means of the variables between combined-exercise-programmed-group and control group through a two-sample t-test and carried out a paired t-test to check if the changes in the variables of two groups before and after 16 weeks are statistically significant. Every statistical test is performed at a significance level of ${\alpha}$=.05. The results are as follows. When it came to metabolic syndrome index, there were statistically meaningful changes in waist measurement, triglyceride, glucose with empty stomach and HDL-C. Also, when it came to autonomic nerve system, there were meaningful changes in all variables. Consequently, it seems that the 16-weeks combined exercise program has positive effects on low level physical strength students.

• Journal of Biosystems Engineering
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• v.22 no.4
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• pp.439-450
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• 1997

Most of Korean feed mill has a pregrind system which was suitable for the processing of less number of ingredients and finished products, and good for the mash type feed product. But industries has been changed in production volume and cost, and also from mash to further processed products such as pelleted and extruded. Therefore, Korea feed industries now should change the process, especially the grinding system from the current pregrind to other grind system, but this change will cost a lot of investment and also loosing current grinding system, and should have production shut down during the construction period. To solve these problems, combined grinding system based on a new model mill has been developed. The combined grind system is combination of pregrind and postgrind system, which has the advantages of those two grind systems, and also which can allow to utilize existing pregrind system continuously without any production interruption due to new postgrind system construction. This newly developed model has been applied to the feed mill expansion project of `B`feed company in 1994, and it was very successful application and showed excellent results as we intended. The new model mill, combined grind system applied can save fixed asset investment because old pregrind system can be used as is, and also can reduce production cost and improve product quality. And the possibility of critical production shut down can be much lowered. Within this new grinding model development, multi-screen combination system has been developed for the better grinding texture quality and safer operation. This new model mill with combined grind system will be applied by most feed manufacturing plant and may enhance their production competitiveness, and the further study and development should be continued.

• Proceedings of the Korean Institute of Intelligent Systems Conference
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• 2003.09a
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• pp.205-208
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• 2003

While multilayer perceptrons (MLPs) have great possibility on the application to speaker verification, they suffer from inferior learning speed. to appeal to users, the speaker verification systems based on MLPs must achieve a reasonable enrolling speed and it is thoroughly dependent on the fast learning of MLPs. To attain real-time enrollment on the systems, the previous two studies have been devoted to the problem and each satisfied the objective. In this paper the two studies are combined md applied to the systems, on the assumption that each method operates on different optimization principle. By conducting experiments using an MLP-based speaker verification system to which the combination is applied on real speech database, the feasibility of the combination is verified from the results of the experiments.

• Journal of the Korean Society of Manufacturing Technology Engineers
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• v.22 no.3
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• pp.421-428
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• 2013

The current vibration reduction methods for positioning systems lead to either complicated motion or the need for additional hardware when the positioning systems carry out frequent short-distance movements. This paper proposes a simple yet efficient vibration reduction method for positioning systems subjected to frequent short-distance movements. The essence of the proposed method is the trapezoidal or triangular velocity profiles, whose acceleration/deceleration rates are designed to be related to the natural frequency of concern. The combined use of the proposed method and the input shaping method is also proposed for the possible application to multi-mode systems. Experiments are performed to validate the proposed method. The simulation and experiments prove that the proposed method is of great use for residual vibration reduction in positioning systems subjected to frequent short-distance movement.

• Journal of Korean Institute of Industrial Engineers
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• v.42 no.6
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• pp.404-411
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• 2016

In footwear manufacturing systems, the upper parts of the shoes are manually sewed on a sub-line while bottom parts are produced by machines such as injection and molding machines on a sub-line before these two parts are combined into complete shoes on a final assembly line. The manual operations for the upper parts lead to a large variability in processing times, resulting in higher work-in-process inventory. In most footwear industries, production lines have been controlled by MRP-based push systems. Some industries attempt to introduce Kanban-based pull systems. This paper identifies the characteristics of the footwear manufacturing processes, and discusses the problems of the current control systems. As an operational alternative, a CONWIP-based control strategy is presented. Simulation experiments are performed to examine the performance of the control strategies.