• ETRI Journal
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• v.33 no.3
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• pp.407-414
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• 2011

In an effort to reduce energy consumption, research into adaptive power management in real-time systems has become widespread. In this paper, a novel dynamic voltage scaling scheme is proposed for multiprocessor systems. Based on the concept of the Nash bargaining solution, a processor's clock speed and supply voltage are dynamically adjusted to satisfy these conflicting performance metrics. In addition, the proposed algorithm is implemented to react adaptively to the current system conditions by using an adaptive online approach. Simulation results clearly indicate that the superior performance of the proposed scheme can strike the appropriate performance balance between contradictory requirements.

• Proceedings of the Korean Operations and Management Science Society Conference
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• 1997.10a
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• pp.63-66
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• 1997

This paper is concerned with the current status and the prospectus of environmental investments in the manufacturing sector. A questionnaire survey was made to identify the concentrated fields of the investments. The collected data were analyzed by a multidimensional scaling method in order to provide a reasonable interpretation on the major factors which characterize the current situation and the prospectus of the investments as well as the relative position of each respondent company in a spatial map. The result tells us most respondents tend to concentrate their attention on end-of-pipe solutions due to technological tangibility and economic efficiency, etc.

• Journal of Energy Engineering
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• v.27 no.1
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• pp.21-32
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• 2018

In this paper, we reported the current technologies of water scaling removal and also water recovery from the flue gases, which are funded by Department of Energy (DOE), USA. Globally, water resources are limited due to the climate change. The potential impacts of climate change is food and water shortages. In the $21^{st}$ century, water shortages and pollution are expected to become more acute as populations grow and concentrate in cities. At present, the water stress increases over 62.0 ~ 75.8% of total water basin area and decreases over 19.7 ~ 29.0%. Many renewable energy sources demand secure water resources. Water is critical for successful climate change mitigation, as many efforts to reduce greenhouse gas emissions depend on reliable access to water resources. Water hardness is one of the major challenge to coal power plants. Department of energy (DOE) funded and encouraged for the development of advanced technologies for the removal of hardness of water (scaling) and also water recovery from the flue gases from coal power plants.

• Advances in Computational Design
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• v.8 no.2
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• pp.133-145
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• 2023

Scaling and similitude large scale structural member to small scale model is considered the most important matter for the experimental tests because of the difficulty in controlling, lack of capacities and expenses, furthermore that most of MSc and PhD students suffering from choosing the suitable specimen before starting their experimental study. The current study adopts to take large scale slab with opening as a case study of structural member where the slab is squared with central squared opening, the boundary condition is fixed from all sides, the load represents by four concentrated force in four corners of opening, as well as, the study adopts Buckingham theorem which has been used for scaling, all the parameters of the problem have been formed in dimensionless groups, the main groups have been connected by a relations, those relations are represented by force, maximum stress and maximum displacement. Finite element method by ANSYS R18.1 has been used for analyzing and forming relations for the large scale member. Prediction analysis has been computed for three small scale models by depending on the formed relations of the large scale member. It is found that Buckingham theorem is considered suitable way for creating relations among the parameters for any structural problem then making similitude and scaling the large scale members to small scale members. Finally, verification between the prediction and theoretical results has been done, it is observed that the maximum deviation between them is not more than 2.4%.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.331-331
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• 2012

With the NAND Flash scaling down, it becomes more and more difficult to follow Moore's law to continue the scaling due to physical limitations. Recently, three-dimensional (3D) flash memories have introduced as an ideal solution for ultra-high-density data storage. In 3D flash memory, as the process reason, we need to use poly-Si TFTs instead of conventional transistors. So, after combining charge trap flash (CTF) structure and poly-Si TFTs, the emerging device SONOS-TFTs has also suffered from some reliability problem such as hot carrier degradation, charge-trapping-induced parasitic capacitance and resistance which both create interface traps. Charge pumping method is a useful tool to investigate the degradation phenomenon related to interface trap creation. However, the curves for charge pumping current in SONOS TFTs were far from ideal, which previously due to the fabrication process or some unknown traps. It needs an optimization and the important geometrical effect should be eliminated. In spite of its importance, it is still not deeply studied. In our work, base-level sweep model was applied in SONOS TFTs, and the nonideal charge pumping current was optimized by adjusting the gate pulse transition time. As a result, after the optimizing, an improved charge pumping current curve is obtained.

• Journal of electromagnetic engineering and science
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• v.11 no.2
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• pp.105-112
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• 2011

In phase-locked frequency synthesizers, a fast-lock technique is frequently employed to overcome the trade-off between a lock-time and a spurious response. The function of fast-lock in a conventional PLL (Phased Lock Loop) IC (Integrated Circuit) is limited by a factor of 16, which is usually implemented by a scaling of charge pumper, and consequently a lock time improvement of a factor of 4 is possible using the conventional PLL IC. In this paper, we propose a novel external active fast-lock loop filter. The proposed loop filter provides, conceptually, an unlimited scaling of charge pumper current, and can overcome conventional trade-off between lock-time and spur suppression. To demonstrate the validity of our proposed loop-filter, we fabricated an X-band frequency synthesizer using the proposed loop filter. The loop filter in the synthesizer is designed to have a loop bandwidth of 100 kHz in the fast-lock mode and a loop bandwidth of 5 kHz in the normal mode, which corresponds to a charge pumper current change ratio of 400. The X-band synthesizer shows successful performance of a lock-time of below 10 ${\mu}sec$ and reference spur suppression below -64 dBc.

• Nuclear Engineering and Technology
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• v.21 no.1
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• pp.32-39
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• 1989

A method for determining the optimum ideal MHD $\beta$limit and the operation conditions is presented for an axisymmetric tokamak reactor with a circular cross section. The $\beta$limit is calculated under the constraints of ideal MHD instability criteria with varying the operation conditions which depend on the toroidal current density distributions. Semiempirical laws deduced from experimental observations are used for the toroidal current density distributions. Analytic derivations of various equations required to determine the $\beta$limit are carried out from the empirical equations. Various distributions of the $\beta$limit are obtained by the numerical calculations for different distributions of the toroidal current density. The resulting values of the maximum $\beta$limited by ideal MHD instabilities are expressed by a scaling law in terms of the tokamak geometry and the safety factor.

• Journal of dental hygiene science
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• v.12 no.4
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• pp.437-442
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• 2012

The current research examines the aching part and the muscle activity that happens during scaling practice subject to 20 dental hygienic students and therefore propose a basic data according to the working attitude of the Dental Hygienist. During the scaling we used the free EMG (BTS Inc., Milan, Italy) to measure the muscle activity, and in order to check the musculoskeletal pain area we used the Nordic-style questionnaire, and the measured research results are as following: At the moment of scaling according to posture the occurrence of the pain showed no difference among the groups elbow, back, leg, knee, ankle/foot but in the neck, shoulder, wrist/hand, waist showed a high difference in the degree of pain according to posture. Results from measuring the muscular activity according to posture, in the group that had a good posture, the trapezius and brachial muscles showed a change according to time, and in the group that had a bad posture a high muscle activity was shown in larynx, trapezius and brachial muscles. In the muscle activity, the changing aspect between the two parts, the group that fulfilled a scaling in a good posture showed a low muscle activity, but in the group that fulfilled the scaling in a bad posture the muscle activity increased excessively. Therefore we examined that when fulfilling a scaling maintaining a bad posture can help in using more effectively the activity of the muscle, in the future I think there is a need to raise the office efficiency by subjecting to dental hyginiest that are in the clinics and performing experiments.

• Journal of dental hygiene science
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• v.17 no.4
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• pp.333-340
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• 2017

The prevalence of periodontal disease was steadily increased. The best prevention methods for periodontal disease are teeth brushing and scaling. The purpose of this study was to investigate the status of scaling experience and related factors among some workers. Total 455 workers in 5 manufacturing companies in Gwangju were selected using convenience sampling method. General characteristics, work-related characteristics, oral health-related characteristics and scaling experience were collected by self-reported questionnaires. Chi-square tests, t-tests and multiple logistic regression analysis were performed to investigate the factors influencing the scaling experience using SPSS software. Statistical significance was defined as a p-value<0.05. The proportion of scaling experience during the past year was 47.0%. In simple analysis, age, current working position, number of oral disease, interest in oral health, use of secondary oral products, oral health screening use, oral health education experience and awareness of scaling inclusion in the National Health Insurance (NHI) coverage were associated with scaling experience. Finally, the odds ratios (ORs) for scaling experience were significantly higher in younger subjects (adjusted OR [aOR], 3.09; 95% confidence internal [CI], 1.60~5.96), assistant manager (aOR, 2.68; 95% CI, 1.55~4.63), subjects with high interest in oral health (aOR, 2.15; 95% CI, 1.02~4.52), subjects with oral health screening use (aOR, 2.76; 95% CI, 1.50~5.11) and awareness of scaling inclusion in the NHI coverage (aOR; 2.91, 95% CI, 1.80~4.72) in multiple logistic regression analysis. Scaling experience was relatively low (47.0%). The related factors with scaling experience were age, working position, use of screening and awareness of scaling inclusion in the NHI coverage. Considering these factors will increase the utilization rate of scaling.

• 한국전기화학회:학술대회논문집
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• 2002.04a
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• pp.39-39
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• 2002