• Economic and Environmental Geology
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• v.47 no.3
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• pp.247-254
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• 2014

The compressibility of fracture in naturally fractured reservoir is larger than the compressibility of matrix in rock, although the compressibility of a typical rock is very small. The effective compressibility including the fracture compressibility should be considered to predict oil recovery correctly. It is hard to quantify changes of fracture aperture and pore volume in reservoir without the effective compressibility. In this study, oil recovery is analyzed by commercial simulator concerning the fracture compressibility based on fracture properties. We found that the effective compressibility affects oil recovery with change of polymer flooding factors such as polymer molar weight, concentration and injection rate. The estimated cumulative oil production is smaller with the effective compressibility than without it. Also, bottomhole pressure decreases rapidly without considering effective fracture compressibility.

• Journal of Korean Society for Atmospheric Environment
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• v.27 no.4
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• pp.454-459
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• 2011

In this study, the recovery rate of Tedlar bag (T) sampler was investigated in comparison to polyester aluminum bag (P) sampler. To derive the comparative data sets for the relative performance between different samplers, a series of calibration experiments were performed by using 1 ppb standard of four offensive reduced sulfur compounds (RSC) odorants ($H_2S$, $CH_3SH$, DMS, and DMDS) along with $SO_2$ and $CS_2$. All the analysis was made by gas chromatography/pulsed flame photometric detector (GC/PFPD) combined with air server/thermal desorber (AS/TD). The measurement data were obtained by loading gaseous standards (1 ppb) at 3 injection volumes (250, 500 and 1,000 mL) at three intervals (0, 24 and 72 hrs). The recovery rates (RR) of P sampler were computed against the slope values of T sampler. According to our analysis, P sampler exhibits slightly enhanced loss relative to T, especially with light RSCs ($H_2S$ and $CH_3SH$). At day 0, RR for the two were 88 and 85%, respectively. Such reduction proceeded rather rapidly in the case of $H_2S$ through time. However, P sampler was more stable to store $SO_2$ unlike others. Despite slightly reduced recovery, P sampler appears as a good replacement of T sampler.

• Proceedings of the IEEK Conference
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• 2001.10a
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• pp.43-47
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• 2001

The waste home appliances including television sets, refrigerators, washing machines and air conditioners have increasingly received environmental concerns in Taiwan. In light of the enforcement of Waste Disposal Act (WDA), the Taiwan Environmental Protection Administration (EPA) has certified 60 recycling/storage facilities and given permission for qualified companies to build six treatment plants around the island. Now the recycling and well treatment home appliances are estimated to be 3,342,369 units until May 31, 2001. This paper describes the present status of waste home appliance recycle and its treatment in Taiwan. The principle guidelines and policies regarding recycling, resource recovery and environmental concerns are presented.

• The Transactions of the Korea Information Processing Society
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• v.6 no.10
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• pp.2618-2629
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• 1999

In this paper, we describe the design and implementation of the FDRA(Fault Detection Recovery based on Agent) running on distributed multimedia environment. DOORAE is a good example for distributed multimedia and multimedia distance education system among students and teachers during lecture. It has primitive service agents. Service functions are implemented with objected oriented concept. FDRA is a multi-agent system. It has been environment, intelligent agents interact with each other, either collaboratively or non-collaboratively, to achieve their goals. The main idea is to detect an error by using polling method. This system detects an error by polling periodically the process with relation to session. And, it is to classify the type of error s automatically by using learning rules. The merit of this system is to use the same method to recovery it as it creates a session. FDRA is a system that is able to detect an error, to classify an error type, and to recover automatically a software error based on distributed multimedia environment.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.29 no.7B
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• pp.650-659
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• 2004

Domestic wireless network environment is changing rapidly while adapting to meet service requirements of users and growth of market. As a result, reliable data transmission using TCP is also expected to increase. Since TCP assumes that it is used in wired networt TCP suffers significant performance degradation over wireless network where packet losses are not always result of network congestion. Especially RTO imposes a great performance degradation of TCP. In this paper, we propose DAC$^{＋}$ and EFR in order to prevent performance degradation by quickly detecting and recovering loss without RTO during fast recovery. Compared with TCP NewReno, proposed scheme shows improvements in steady-state in terms of higher fast recovery Probability and reduced response time.

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2000.04a
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• pp.106-108
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• 2000

• Proceedings of the Korean Society of Environment and Ecology Conference
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• 2000.04a
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• pp.165-167
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• 2000

• Environmental Engineering Research
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• v.22 no.3
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• pp.288-293
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• 2017

In this study, we report the industrial application of an efficient technology for the recovery of gallic acid from Chinese nutgall processing wastewater. The recovery of gallic acid by industrial scale extraction and stripping devices was performed, with tributyl phosphate as the extractant and kerosene as the diluent. The results showed that the theoretical extraction stage was four, while the theoretical stripping stage was two. A closed-cycle system was studied for the continuous countercurrent extraction and stripping, with a five-stage extraction device and a three-stage reflux stripping device. The results showed that the multistage extraction-stripping system could steadily run for a long period, the average gallic acid level in the raffinate was $0.85g{\cdot}L^{-1}$, and the gallic acid content recovered in the strip liquor was higher than $120g{\cdot}L^{-1}$. The average extraction yield of gallic acid was 94.14%. When the strip liquor was used as raw material for production, the average production yield increased by 8.64%. In addition, after extraction, the $COD_{Cr}$ in the wastewater decreased by 38.19%, and the biodegradability of wastewater improved by 1.6 times. This study provided a new impetus for the sustainable development of the Chinese nutgall processing industry.

• Journal of Korean Society for Atmospheric Environment
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• v.18 no.E4
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• pp.181-190
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• 2002

A novel portable device for the direct measurement of alveolar breath carbon monoxide (CO) was developed. The major components of the device include a mouthpiece, non-rebreathing two-way valve, Teflon tube, and CO dosimeter. An alveolar CO measurement can be completed within 1.5 min when using the proposed device and measurement protocol. Measurements could be read to the nearest 0.1 ppm. Humidity did not influence the CO measurements taken by the CO dosimeter, plus there were no problems associated with the recovery and carryover of CO through the device. The criterion for significance in statistical analyses was p< 0.05. The average recovery was 103 and 99% for recovery and carryover experiments, respectively. Test results using the proposed alveolar CO measurement system reflected a good reproducibility. This reproducibility was also supported by the finding that the relative standard deviations (RSDs) of the data sets were less than 7％ for the loss experiment and less than 8% for the carryover experiment. Consequently, it would appear that the proposed device can be effectively applied to measure CO levels found in breath, thereby overcoming several disadvantages associated with the conventional bag and adsorbent tube sampling methods.

• Journal of Digital Contents Society
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• v.6 no.1
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• pp.85-88
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• 2005

The requirement of distributed multimedia applications is the need for sophisticated QoS(quality of service) management. In terms of distributed multimedia systems, the most important catagories for quality of service are a timeless, volume, and reliability. In this paper, we discuss a method for increasing reliability through fault tolerance. We describe the desist and implementation of the ERA running on distributed multimedia environment ERA is a system is able to recover automatically a software error based on distributed multimedia. This paper explains a performance analysis of an error recovery system running on distributed multimedia environment using the rule-based DEVS modeling and simulation techniques. In DEVS, a system has a time base, inputs, states, outputs, and functions.