• Journal of Biosystems Engineering
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• v.35 no.6
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• pp.401-407
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• 2010

In this study, computer simulations were conducted to assess the use of a circulating concurrent-flow dryer for rapeseed drying and to determined the effect of this drying method on the germination ratio of rapeseed after the drying process was complete. The simultaneous heat and mass transfer between air and rapeseed in a concurrent-flow dryer was examined by simulation. The drying simulation was based on several parameters with sequent time series. Equations concerning air psychrometrics, physical properties, thermal properties, equilibrium moisture content, thin layer drying of rapeseed, etc. were all combined to solve the simulation models. Based on energy and mass transfer in the concurrent-flow drying model, a simulation program for the circulating concurrent-flow rapeseed dryer was built along with a detailed description of the mathematical solution to the model. A pilot scale circulating concurrent-flow dryer(200 kg/batch) was used to verify the fitness of the simulation program. A comparison between the experimental data and the model predicted results was presented and discussed. The drying parameters and germination ratio were analyzed and the accuracy of the simulation program was evaluated. The simulation program proved to be reliable and was shown to be a convenient tool for predicting rapeseed drying and germination ratio of rapeseed in a concurrent-flow dryer.

• Journal of Biosystems Engineering
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• v.34 no.5
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• pp.358-362
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• 2009

This study was conducted to evaluate the performance of a 12 tons capacity circulating concurrent flow rice dryer. An actual scale dryer with the capacity of 12 tons was developed to obtain a faster drying rate of 0.8~1.2%(w.b.)/h, while maintaining a lower drying energy consumption of 5,000 kJ/kg-water and achieving a drying quality that was comparable to a conventional cross-flow rice dryer. The Test-1 was conducted at $110^{\circ}C\;-\;20\;cmm/m^2$ and the Test-2 was conducted at $120-110-100-90^{\circ}C\;-\;20\;cmm/m^2$ under the same conditions as Test-1. In Test-1, the drying rate, drying energy consumption and crack ratio were 0.98 %(w.b.)/h, 4,573 kJ/kg-water and 3.2%, respectively. In Test-2, the drying rate, drying energy consumption and crack ratio were 0.74 %(w.b.)/h, 4,790 kJ/kg-water and 4.0%, respectively. The results of these tests demonstrated that this concurrent-flow dryer reached the desired drying rate, drying energy consumption and crack ratio.

• Korean Journal of Computational Design and Engineering
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• v.3 no.4
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• pp.283-292
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• 1998

The engineering process including design, analysis/evaluation and manufacturing activities is becoming one of the key issues to embody a concurrent engineering concept. This paper proposes a framework to integrated the complicated engineering design and manufacturing processes under the concurrent engineering environment. The framework offers the following facilities: (1) to represent the complicated engineering process (2) to coordinate design activities and execute the process in a distributed environment (3) to support a communication among the related engineers. The engineering processes is depicted using process flow graphs that consist in tasks and the corresponding input and output data. The engineering activities in the defined processes can be executed in a distributed environment through process controller of the framework. Engineers can communicate to suggest their opinions and to exchange product information in the framework. We have conformed the CORBA standard to integrate various distributed engineering the and communicate among them, and used a Java to support the platform independent environment on the Internet. Since the proposed framework an be a formal approach to integrate the engineering processes by providing formalism, parallelism, reusability, and flexibility, it can be effectively applied to embody the concurrent engineering concept in a distributed environment.

• Journal of Korean Society for Quality Management
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• v.32 no.3
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• pp.141-152
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• 2004

This study describes process and method to establish concurrent and/or sequential schedule planning for the system design process of the EIA632 standard. For this purpose, the study suggest Process and method that are context analysis of standard process, interface definition from activity decomposition, integration of related activities, and definition of concurrent and/or sequential work flow. The proposed process and method will contribute to minimize time loss that is emerged from activities iteration.

• Proceedings of the IEEK Conference
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• 1998.06a
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• pp.883-886
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• 1998

We introduce a high level synthesis methodlogoy for automatic synthesis of asynchronous circuits form a language based on CSP. The input language is a high level concurrent algorithmic specification that can model complex concurrent control flow, logical and arithmetic computation and communications between them. This specification is translated into petri net which has actions. These actions are refined to synthesize the controllers and to allocate the data resources. We use the automatic synthesis through signal transition graphs (STGs) that allows to take advantage of logic synthsis methods to optimize the circuit.

• Journal of KIISE:Software and Applications
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• v.26 no.1
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• pp.106-106
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• 1999

When we design real-time software target system is analyzed and then we structure sequential executive modules into concurrent tasks. As a result of the analysis, control flow and dataflow diagram based on the RTSA notation is produced. This diagram is structured into concurrenttasks under the condition that performance problem is not serious. The criteria structuring concurrenttasks are introduced as Concurrent Design Approach for Real-Time System(CODARTS) by Gomaa.But structuring concurrent tasks using the criteria of CODARTS is somewhat difficult because thecriteria are dependent on designer's experience. CODARTS is an wide-range and abstractmethodology. As a result, the design can be inconsistent and peoples can understand it differently Inthis paper, we restructure the CODARTS methodology, propose a revised CODARTS structure andrepresent the task structuring steps for this new framework to overcome the understanding andinconsistency problems. The revised CODARTS framework and task structuring steps can be used toautomate the design of real time concurrent software systems. Finally, we show an example of taskstructuring in revised CODARTS framework.

• Journal of Industrial Technology
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• v.43 no.1
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• pp.49-55
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• 2023

Cluster tools are extensively employed in various wafer fabrication processes within the semiconductor manufacturing industry, including photo lithography, etching, and chemical vapor deposition. Contemporary fabrication facilities encounter customer orders with technical specifications that are similar yet slightly varied. Consequently, modern fabrications concurrently manufacture two or three different wafer types using a cluster tool to maximize chamber utilization and streamline the flow of wafer lots between different process stages. In this review, we introduce two methods of concurrent processing of multiple wafer types: 1) concurrent processing of multiple wafer types with different job flows, 2) concurrent processing of multiple wafer types with identical job flows. We describe relevant research trends and achievements and discuss future research directions.

• The Korean Journal of Physiology
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• v.9 no.2
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• pp.33-39
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• 1975

Changes of urinary aldosterone excretion, concurrent sodium and potassium excretion following furosemide administration were studied in normotensive young Korean with high sodium intake, moderate sodium restriction and marked sodium depletion. After intravenous injection of furosemd 40mg, plasma and urine samples were collected at every thirty minutes for two hours. Plasma-and urinary aldosterone, electrolyte concentration and urine flow rate were measured by means of radioimmunoassay or flamephotometry. Relations of urinary aldosterone to concurrent sodium or potassium/sodium ratio, and of urinary aldosterone to concurrent plasma aldosterone activity were studied. Following were the results: 1. Furosemide administration resulted in a increased urinary aldosterone concentration and unchanged or somewhat decreased sodium concentration in course of time after the injection. 2. Urinary potassium concentration showed initial decrease and subsequent increase in course of time after furosemide administration and it resulted in a gradual increase in urinary potassium/sodium ratio. 3. Studying the relations between urinary aldosterone excretion and potassium/sodium excretion ratio, or sodium excretion were meaningless because of the urinary flow rate after the injection was decreased with time course. 4. Furosemide administration showed a good relationship of urinary aldosterone concentration to concurrent potassium/sodium ratio rather than concurrent sodium concentration in subjects with sodium restriction, but no meaningful relationship was detected in subjects with high sodium intake because increasing rate of the ratio was not so wide. 5. Furosemide also resulted a reasonable relation of plasma aldosterone concentration to concurrent urinary aldosterone concentration especially during low sodium intake. 6. Above results suggested that relation of urinary aldosterone concentration to K/Na ratio following furosemide administration during sodium restriction is significant and has a benefit to reduce the variation induced by kalemic change showing in the diragram for daily aldosterone to sodium excretion.

• 한국전산유체공학회:학술대회논문집
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• 2010.05a
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• pp.517-523
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• 2010

Recently, the rapid evolution of computational fluid dynamics (CFD) has enabled its key role in industries and predictive sciences. From diverse research disciplines, however, are there strong needs for integrated analytical tools for multi-phenomena beyond simple flow simulation. Based on the concurrent simulation of multi-dynamics, multi-phenomena beyond simple flow simulation. Based on the concurrent simulation of multi-dynamics, multi-physics and multi-scale phenomena, the multi-phenomena CFD technology enables us to perform the flow simulation for integrated and complex systems. From the multi-phenomena CFD analysis, the high-precision analytical and predictive capacity can enhance the fast development of industrial technologies. It is also expected to further enhance the applicability of the simulation technique to medical and bio technology, new and renewable energy, nanotechnology, and scientific computing, among others.

• Journal of Biosystems Engineering
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• v.32 no.5
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• pp.309-315
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• 2007

This study was performed to develop a simulation model of circulating concurrent-flow rice dryer. The simulation model consists of drying model, tempering model and crack prediction model. The drying and tempering models were developed based on mathematical analysis, and the crack prediction model was developed by thin layer drying tests. Rice drying tests were done with three replications by use of a pilot scale dryer of holding capacity of 700 kg. Experimental values for moisture content, rice temperature, rice crack, and drying energy were compared with predicted values by simulation model. The RMSEs of predicted moisture contents were ranged from 0.5807% (d.b.) to 1.1951% (d.b.). and the coefficients of determination were 0.9688 to 0.9812. The RMSEs of predicted rice temperatures at the exit of the drying chamber were 1.83 to $3.81^{\circ}C$ and the coefficients of determination were 0.8834 to 0.9482. The results for moisture contents and rice temperatures showed very good relationships between predicted values and experimental values. The RMSEs of predicted value of crack ratio were 0.4082 to 0.7967% and the coefficients of determination were 0.8742 to 0.9547.