• Journal of the Korean Society for Precision Engineering
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• v.11 no.4
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• pp.126-137
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• 1994

Performance management of computer networks is intended to improve a given network performance in order for more efficient information exchange between subsystems of an integrated large-scale system. Importance of perfomance management is growing as many functions of the large- scale system depend on the quality of communication services provided by the network. The role of performance management is to manipulate the adjustable protocol parameters on line so that the network can adapt itself to a dynamic environment. This can be divided into two subtasks : performance evaluation to find how changes in protocol parameters affect the network performance and decision making to determine the magnitude and direction of parameter adjustment. This paper is the first part of the two papers focusing on conceptual design, development, and evaluation of performance management for token bus networks. This paper specifically deals with the task of performance evaluation which utilizes the principle of perturbation analysis of discrete event dynamic systems. The developed algorithm can estimate the network performance under a perturbed protocol parameter setting from observations of the network operations under a nominal parameter setting.

• Journal of the East Asian Society of Dietary Life
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• v.21 no.5
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• pp.746-755
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• 2011

A survey on the status of sanitary education and recognition and perceived performance of cooking operations related to sanitation for cooks at nine deluxe hotels in the Seoul area was conducted. The frequency of a food sanitary training program inside the hotel was 94.0%, and the frequency of training was 'once a month' at 68.5%. The program was taught by a hygienist in the hotel (62.7%), and 64.2% of cooks always attended. Cooks' recognition of HACCP was 3.52, and the importance of education on HACCP was higher at 3.77. Cook's' level of sanitary management was satisfactory with an average of 3.83 out of 5 in a Likert scale. The results showed a high average (4.08) for importance of personal hygiene during cooking, but satisfaction of personal hygiene was rather low at 3.92. Cooks' recognition of food sanitation in work field was very high at 4.15. The average scale of recognition on personal hygiene was 4.36, and out of 10 items related to personal hygiene, 'maintaining hand hygiene' showed the highest recognition (4.43). In a performance scale, the average was 4.24, and 'performing annual health examination' was the highest at 4.38. Perceived recognition of 18 items related to food sanitation had an average of 4.41, whereas the average for performance was lower at 4.31. Perceived recognition of 12 items related to cooking equipments had an average of 4.39, and average scale of performance was 4.28. Therefore, cooks' high recognition of food sanitation but rather low recognition of satisfaction of personal hygiene and perceived performance indicated that systematic sanitation management monitoring tools are necessary for higher performance.

• Journal of Korean Academy of Nursing
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• v.34 no.6
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• pp.964-973
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• 2004

Purpose: This study was aimed to identify the major factors affecting performance in health promoting behaviors in women workers at small-scale industries. Method: This study was based on the Pender's Health Promotion Model. The subjects for this study were 251 women workers at 23 small-scale industries in Busan city. The data for this study was collected from July 15th to August 15th 2003 by structured questionaries, and were analyzed with ANOVA, t-test, Pearson' correlation coefficient, and multiple Regression in the SPSS/WIN 10.0. Result: The mean performance of the health promoting behavior was 2.56. The factors related to the performance of the health promoting behaviors were social support, marital status, status of owning a house, perceived barriers to action, working time, and self-efficacy, and they explained 58.4% of the variance of the health promoting behaviors. Conclusion: The mean performance of the health promoting behavior seemed to be low, and the most important variable related to health promoting behaviorsof women working at a small-scale industry was social support. Therefore, intervention programs to increase the social support for women worker need to be developed.

• Transactions of the Korean Society for Noise and Vibration Engineering
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• v.18 no.2
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• pp.255-262
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• 2008

In this study, seismic response control performance of decentralized response-dependent MR damper which generates the control force using only the response of damper-installed floor, was experimentally investigated through the tests of a full-scale structure installed with large MR dampers. The performance of the decentralized control algorithm was compared to those of the centralized ones such as Lyapunov, modulated homogeneous friction, and clipped-optimal control. Hybrid mass damper were controlled to induce seismic response of the full-scale structure under El Centro earthquake. Experimental results indicated that the proposed decentralized MR damper provided superior or equivalent performance to centralized one in spite of using damper-installed floor response for calculating input voltage to MR damper.

• Journal of Biosystems Engineering
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• v.37 no.6
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• pp.365-372
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• 2012

Purpose: Performance of slurry composting and biofiltration with methane production (SCB-M) using swine manure and sawdust was evaluated. The suitable specific liquid input (SLI) was determined at lab-scale SCB. Method: In lab-scale SCB, the SLI test was performed at liquid input rate of 0.04, 0.09, $0.17cc/cm^3$ with constant sawdust volume. In pilot-scale SCB-M, the swine manure was fed to methane digester at organic loading rate (OLR) of 0.25-0.5 g VS/L/d. The effluent from methane digester was filtered using SCB. Results: The SLI at $0.04cc/cm^3$ showed good performance in terms of retention time. In pilot-scale SCB, the removal of $NH_3$-N and total nitrogen (T-N) was found to be around 59% and 28%, respectively. Similarly, volatile fatty acid (VFA) and total chemical oxygen demand (TCOD) removal was found be 56% and 43%, respectively. Conclusions: For SCB-M process, the SLI of $0.04cc/cm^3$ is recommended. The performance of swine manure treatment was improved more by using SCB-M system than using methane digester only.

• KEPCO Journal on Electric Power and Energy
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• v.5 no.3
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• pp.229-233
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• 2019

Large-scale High Temperature Superconducting (HTS) wind power generators suffer from high electromagnetic force and high torque due to their high current density and low rotational speed. Therefore, the torque and Lorentz force of HTS wind power generators should be carefully investigated. In this paper, we proposed a Performance Evaluation System (PES) to physically test the structural stability of HTS coils with high torque before fabricating the generator. The PES is composed of the part of a pole-pair of the HTS generator for estimating the characteristic of the HTS coil. The 10 MW HTS generator and PES were analyzed using a 3D finite element method software. The performance of the HTS coil was evaluated by comparing the magnetic field distributions, the output power, and torque values of the 10 MW HTS generator and the PES. The magnetic flux densities, output power, and torque values of the HTS coils in the PES were the same as a pole-pair of the 10 MW HTS generator. Therefore, the PES-based evaluation method proposed in this paper can be used to estimate the critical characteristics of the HTS generator under high magnetic field and high torque before manufacturing the HTS wind turbines. These results will be used effectively to research and manufacture large-scale HTS wind turbine generators.

• 한국신재생에너지학회:학술대회논문집
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• 2008.05a
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• pp.138-141
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• 2008

The effects of design parameters for small scale hydro power(SSHP) plants due to rainfall condition have been studied. The model to predict hydrologic performance for SSHP plants is used in this study. The results from analysis for rainfall conditions based on Weibull distribution show that the capacity and load factor of SSHP site had large difference between the variation of shape and scale parameter. Especially, the hydrologic performance of SSHP site due to variation of shape parameter varied more sensitive than the case of variation of scale parameter. And also, the methodology represented in this study can be used to decide the primary design specifications of SSHP sites.

• Proceedings of the KSME Conference
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• 2000.04b
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• pp.13-18
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• 2000

The objective of the Present study is to investigate the performance of electronic scale mitigation unit(ESMU), which reduces the amount of scale in a heat exchanger. A plate heat exchanger with 20 thermal plates is used for the tests. In order to accelerate the rate of fouling in a laboratory test artificial hard water of 2000 ppm(as $CaCO_3$) is recirculated at a flow rate 5L/min throughout the tests. The overall heat trans(or coefficients and fouling factors are examined. Results show that the ESMU technology can significantly reduce the scale deposits.

• Journal of the Korean Solar Energy Society
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• v.28 no.1
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• pp.43-49
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• 2008

The effects of design parameters for small scale hydro power(SSHP) plants due to rainfall condition have been studied. The model to predict hydrologic performance for SSHP plants is used in this study. The results from analysis for rainfall conditions based on Weibull distribution show that the capacity and load factor of SSHP site had large difference between the variation of shape and scale parameter. Especially, the hydrologic performance of SSHP site due to variation of shape parameter varied more sensitive than the case of variation of scale parameter. And also, the methodology represented in this study can be used to decide the primary design specifications of SSHP sites.

• The Journal of the Institute of Internet, Broadcasting and Communication
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• v.11 no.2
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• pp.113-118
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• 2011

This paper has analyzed recognizing performance depending on the size of iris codes extracting by iris recognition algorithm using scale-space filtering. The iris images were created through pre-processing, the features were extracted by scale-space filtering, and the codes of 16 sizes were generated. The generated code's performance was compared for each code to calculate FAR and FRR by matching method utilizing Hamming distance. Every code had little overlapping portion between same person and other persons group so that the proposed algorithm's superiority was proved, and the performance of iris codes was analyzed for each size focused on convenience to use when implementing in realization. In addition, the iris codes suitable to iris recognition system that is high-reliable and is able to reduce user's inconvenience due to mis-rejection has been presented considering for commercialization.