• Structural Engineering and Mechanics
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• v.66 no.4
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• pp.505-513
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• 2018

Steam flooding is widely used in heavy oil reservoir with coupling effects among the formation temperature change, fluid flow and solid deformation. The effective stress, porosity and permeability in this process can be affected by the multi-physical coupling of thermal, hydraulic and mechanical processes (THM), resulting in a complex interaction of geomechanical effects and multiphase flow in the porous media. Quantification of the state of deformation and stress in the reservoir is therefore essential for the correct prediction of reservoir efficiency and productivity. This paper presents a coupled fluid flow, thermal and geomechanical model employing a program (MATLAB interface code), which was developed to couple conventional reservoir (ECLIPSE) and geomechanical (ABAQUS) simulators for coupled THM processes in multiphase reservoir modeling. In each simulation cycle, time dependent reservoir pressure and temperature fields obtained from three dimensional compositional reservoir models were transferred into finite element reservoir geomechanical models in ABAQUS as multi-phase flow in deforming reservoirs cannot be performed within ABAQUS and new porosity and permeability are obtained using volumetric strains for the next analysis step. Finally, the proposed approach is illustrated on a complex coupled problem related to steam flooding in an oil reservoir. The reservoir coupled study showed that permeability and porosity increase during the injection scenario and increasing rate around injection wells exceed those of other similar comparable cases. Also, during injection, the uplift occurred very fast just above the injection wells resulting in plastic deformation.

• Korean Chemical Engineering Research
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• v.52 no.2
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• pp.154-165
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• 2014

Development of unconventional natural resources such as shale gas, shale oil and coal bed methane, has been activated and improved the productivity due to the recent technology advance in horizontal drilling and hydraulic fracturing. However, the flowback water mixed with chemical additives, and the brine water containing oil, gas, high levels of salts and radioactive metals is produced during the gas production. Potential negative environmental impact due to large volumes of the produced wastewater is increasingly seen as the major obstacles to the unconventional natural resource development. In this study an integrated framework for the flowback and brine water treatment is proposed, and we reviewed the upcoming state of the art technology in water treatment. Basic separation processes which include not only membrane, evaporation, crystallization and desalination processes, but the potential water reuse and recycling techniques can be applied for the unconventional natural resource industry.

• Journal of the Korean Society of Groundwater Environment
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• v.6 no.3
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• pp.152-157
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• 1999

Oil leaked from underwound storage tanks and leachate from sanitary landfills have been known as contaminant sources of the high-quality groundwater resources. The mobility of contaminants in the aquifer largely depends on the groundwater flow and the determination of associated hydraulic parameters is essential for a proper remediation of contaminated grnundwater. This study aimed at determining an optimum set of hydraulic parameters for an unconfined sandy aquifer of a laboratory scale through comparison of various methods. Results showed that the specific yield obtained from gravity drainage experiment was an average of 0.20 with minor variations in aquifer depths. and the permeabilities obtained from Dupuit approximation and slug test gave similar values of 5.33 cm/min and 5.85 cm/min but the constant head method gave 0.17 cm/min, which is much ion than the other methods. This experimental evidence reveals that the permeability of the unconfined sandy aquifer could be accurately determined by Dupuit assumption or slug tut rather than by constant head method conducted for a disturbed separate soil column.

• Journal of Drive and Control
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• v.17 no.2
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• pp.55-62
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• 2020

There are two types of IMV for MCV, the spool type and the poppet type. The spool type is used in the existing excavator MCV and easily meets large-capacity flow conditions, but has a flow force problem which affects the spool control. The poppet type stably blocks the flow and has excellent rapid response. However, the larger the capacity, the larger the diameter of the poppet needed, requiring a strong spring to withstand the oil pressure. In this study, a bi-directional three-stage IMV for MCV that can be used in medium and large hydraulic excavators was proposed. This is a poppet type, enabling bi-directional flow control and resolves the problem of proportional solenoid suction force limitation. To investigate the validity of the proposed valve, the system was mathematically modeled and the static and dynamic characteristics were investigated through the simulation using commercial software. It has been concluded that the reverse flow is possible in a regeneration circuit and that the proposed IMV can be used to perform various excavation modes.

• The KSFM Journal of Fluid Machinery
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• v.19 no.6
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• pp.68-74
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• 2016

Hydraulic fracturing of wells during oil and gas (O&G) exploration consumes large volumes of fresh water and generates larger volumes of contaminated wastewater with high salinity. It is critical to treat and reuse the O&G wastewater in a cost-effective and environmentally sound manner for sustainable industrial development and for meeting stringent regulations. Recently, forward osmosis (FO) has been examined if it is a promising solution for treatment and desalination of complex industrial streams and especially fracturing flowback and produced waters. In the present study, the performances of a plate-and-frame FO membrane element and a module (6 elements combined in series) were investigated for concentrating high TDS wastewater. An FO module has achieved up to 64 % water recovery (i.e., concentration factor of 2.76) from 10,000 ppm wastewaters and can concentrate feed streams salinities to greater than 30,500 ppm.

• The Journal of the Korea institute of electronic communication sciences
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• v.15 no.5
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• pp.949-958
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• 2020

The functions of shock absorbers are to dampen body, suspend motions, dissipate impact energy, and control tire force variation. During the operation, hydraulic oil is passed between the chambers via a flow restrictions. Therefore the damping force characteristics of shock absorber is determined by the characteristics of orifices and flow restrictions. The uncertainty in design variable affects the performance of suspension system strongly. But, the researches about the influence of uncertainty in design variable such as a fluid restriction's property of shock absorber, on the suspension system performance was hardly ever proposed. In this paper, we used statistical method of Latin Hypercube sampling, and the effects of design variables uncertainty on the performance of suspension system was presented.

• Journal of Applied Reliability
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• v.12 no.3
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• pp.201-213
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• 2012

A gear type lubrication pump is an essential component of the powertrain and has a major role for supplying oil to the gears and bearings in automatic transmission with a hydraulic clutch. Therefore, the durability test code design of lubrication pump is very important to ensure the reliability of the entire transmission and the vehicle. In this study, the design process for the life testing of lubrication pump has been generalized by four steps. The four design steps of the life testing of lubrication pump consist of the configuration of load spectrum, rain flow counting and analysis of load level, the equivalent damage assessment and test code generation. In fact, the load spectrum should be obtained from the field operating condition but that kind of data is the top secret of manufacturers. This is not open to the public in general. So we could use the artificially simulated load spectrum instead of field obtained one and focused on the development of the general process for designing the life test of a gear type lubrication pump. Reliability goals for lubrication pump, pressure, torque, temperature and load spectrum, if present, as appropriate for the given test conditions, accelerated life testing for the lubrication pump can be designed by the developed design steps.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.520-523
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• 2000

Phenol and other phenolic compounds are common constituents of aqueous effluents from processes such as polymeric resin production, oil refining and cokeing plants. Phenol is a both toxic and lethal of fish at relatively low concentrations e.g. 5-25 mg/L and imparts objectionable tastes to drinking water at far lower concentration. Therefore, the treatment of phenol effluent is important. Among the various techniques of phenol wastewater treatment, microbial teratment is a popular process. The breakdown of phenols by microorganisms has recived considerable attention, because of its biochemical interest and its industrial importance in effluent treatment. This research was performed to investigate the dynamics of microbial community, biofilm growth and the comparison of phenol removal efficiency by RBC (Rotating Biological Contactor) using Rhodococcus sp. EL-GT The experiment was carried out at rotating speed of 10ppm and hydraulic retention time of 7 hours. As time passed, phenol removal efficiency was gained highly. The RBC using Rhodococcus sp. EL-GT completely degraded 15 mM.

• Transactions of The Korea Fluid Power Systems Society
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• v.4 no.4
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• pp.1-7
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• 2007

Flow rate is one of the important variables for precise motion control and detection of the faults and fluid loss in many hydraulic components and systems. But in many cases, it is not easy to measure it directly. The orifice area of a servo valve by which the fluid flows is one of key factors to monitor the flow rate. In this paper, we have constructed an estimation algorithm for the effective orifice area by using the model of a servo valve cylinder control system and Kalman filter algorithm. Without geometry information about the servo valve, it is shown that the effective orifice area can be estimated by using only displacement and pressure data corrupted with noise. And the effect of the biased sensor data and system parameter errors on the estimation results are discussed. The paper reveals that sensor calibration is important in accurate estimation and plausible parameter data such as oil bulk modulus and actuator volume are acceptable for the estimation without any error. The estimation algorithm can be used as an useful tool for detecting leakage, monitoring malfunction and/or degradation of the system performance.

• Proceedings of the Korean Geotechical Society Conference
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• 2004.03b
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• pp.11-19
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• 2004

When pile foundation constructed by driving method, it is desirable to perform monitoring and estimation of pile drivability and bearing capacity using some suitable tools. Dynamic Pile Monitoring yields information regarding the hammer, driving system, and pile and soil behaviour that can be used to confirm the assumptions of wave equation analysis. Dynamic Pile Monitoring is performed with the Pile Driving Analyser. The Pile Driving Analyser (PDA) uses wave propagation theory to compute numerous variables that fully describe the condition of the hammer-pile-soil system in real time, following each hammer impact. This approach allows immediate field verification of hammer performance, driving efficiency, and an estimate of pile capacity. The PDA has been used widely as a most effective control method of pile installations. A set of PDA test was performed at the site of Donghea-1 Gas Platform Jacket which is located east of Ulsan. The drilling core sediments of location of jacket subsoil are composed of mud and sand, silt. In this case study, the results of PDA test which was applied to measurement and estimation of large diameter open ended steel pipe pile driven by underwater hydraulic hammer, MHU-800S, at the marine sediments were summarized.