• Journal of Electrical Engineering and Technology
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• v.13 no.3
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• pp.1079-1088
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• 2018

A line overload emergency control strategy based on the source-load synergy coefficient is proposed in this paper. First, the definition of the source-load synergy coefficient is introduced. When line overload is detected, the source-load branch synergy coefficient and source-load distribution synergy coefficient are calculated according to the real-time operation mode of the system. Second, the generator tripping and load shedding control node set is determined according to the source-load branch synergy coefficient. And then, according to the line overload condition, the control quantity of each control node is determined using the Double Fitness Particle Swarm Optimization (DFPSO), with minimum system economic loss as the objective function. Thus load shedding for the overloaded line could be realized. On this basis, in order to guarantee continuous and reliable power supply, on the condition that no new line overload is caused, some of the untripped generators are selected according to the source-load distribution synergy coefficient to increase power output. Thus power supply could be restored to some of the shedded loads, and the economic loss caused by emergency control could be minimized. Simulation tests on the IEEE 10-machine 39-bus system verify the effectiveness and feasibility of the proposed strategy.

• IMMUNE NETWORK
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• v.12 no.6
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• pp.240-246
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• 2012

Natural killer (NK) cells play a pivotal role in early surveillance against virus infection and cellular transformation, and are also implicated in the control of inflammatory response through their effector functions of direct lysis of target cells and cytokine secretion. NK cell activation toward target cell is determined by the net balance of signals transmitted from diverse activating and inhibitory receptors. A distinct feature of NK cell activation is that stimulation of resting NK cells with single activating receptor on its own cannot mount natural cytotoxicity. Instead, specific pairs of co-activation receptors are required to unleash NK cell activation via synergy- dependent mechanism. Because each co-activation receptor uses distinct signaling modules, NK cell synergy relies on the integration of such disparate signals. This explains why the study of the mechanism underlying NK cell synergy is important and necessary. Recent studies revealed that NK cell synergy depends on the integration of complementary signals converged at a critical checkpoint element but not on simple amplification of the individual signaling to overcome intrinsic activation threshold. This review focuses on the signaling events during NK cells activation and recent advances in the study of NK cell synergy.

• Proceeding of KASS Symposium
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• 2005.05a
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• pp.69-76
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• 2005

This paper deals with a problem about synergy effect in design and engineering. So far a design processing is paralleled to both in Korea, A cooperation between concept design and working plan must be kept up all the way. From three Personally designed footbridges 1 will make clear a total problem for throughout design processing. If we must solve a gaps between technology and art for structural design, we can get an unexpected result. It will be synergy effect between art and technology, design and engineering.

• Journal of Information Technology Applications and Management
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• v.16 no.4
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• pp.185-203
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• 2009

The literature reveals that service quality is critical determinants affecting customer satisfaction in the retail industry. Recent online B2C studies also show that service quality significantly influences online customer satisfaction. However, research on analyzing antecedents to determine the service quality level of online shopping has not been sufficiently reported. Moreover, the offline synergy effect on the Internet shopping mall has been presented mostly at a conceptual level. The purpose of this study is to investigate key managerial variables exploiting offline synergy, including pure online attributes, that impact on service quality of the click and mortar Internet shopping mall. A survey was conducted for empirical validation of the hypotheses. The results indicate that core offline synergy factors significantly enhance the perceived service quality level of the Internet shopping mall. Implications, limitations, and future research directions are also discussed.

• The Journal of Korean Academy of Prosthodontics
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• v.40 no.1
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• pp.79-87
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• 2002

The purpose of this study was to investigate the color stability of composite resins used widely as esthetic restorative material. Surefil(Dentsply, U.S.A.), Esthet X(Dentsply, U.S.A.), Filtek P60(3M, U.S.A.) , Filtek Z250(3M, U.S.A.), Synergy Compact(Coltene, Switzerland), and Synergy Duo(Coltene, Switzerland) were chosen for this study. Thirty six specimens($7mm{\times}2mm$) of each composite resin were fabricated and polished after polymerization. Treatment conditions designed for this study were thermocycling, methylene blue staining, and filtered coffee staining. The color changes before and after treatment were measured by colorimeter(colorimeter, Model Tc-6Fx, Tokyo Denshoku Co.) and analyzed. The followings were drawn from this study: 1. The color changes of Filtek Z250, Surefil, Filtek P60 and Esthet X after thermocycling for 3 weeks were greater than those of the others. 2. The color changes of Surefil and Esthet X after methylene blue stainig and those of Surefil, Filtek Z250 and Filtek P60 after coffee staining were great. 3. The color changes or Synergy Duo and Synergy Compact after thermocycling and coffee staining were relatively lesser than those of other composite resins.

• Korean Journal of Applied Biomechanics
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• v.26 no.2
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• pp.175-181
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• 2016

Objective: The aim of this study was to investigate age-related changes of multi-finger synergy during a constant force production task with and without an additional mechanical constraint. Method: Fourteen elderly subjects (age: $78.50{\pm}4.63yrs$, height: $157.29{\pm}8.97cm$, weight: $65.13{\pm}6.93kg$) and 14 young subjects (age: $21.13{\pm}1.35yrs$, height: $171.57{\pm}8.43cm$, weight: $70.29{\pm}16.77kg$) participated in this study. The subjects were asked to place their index and middle fingers on two force transducers fixed on a small non-moving teeterboard and produce 10 N by pressing the sensors while watching force feedback on a computer screen under the no additional constraint condition (NAC). The subjects also performed the same task with an additional mechanical constraint (AC) where the subjects were asked to balance a teeterboard that could be rotated by finger forces. An uncontrolled manifold approach was used to calculate within-trial and between-trial multi-finger synergy indices, variance in uncontrolled subspace ($V_{UCM}$), and variance in subspace orthogonal to UCM subspace ($V_{ORT}$). Two-way repeated measured ANOVA was performed with the within-factor of task condition (with and without an additional constraint) and the between factor of groups (elderly and young). Results: The elderly group showed significantly increased within-trial $V_{ORT}$ in AC compared with NAC (p < .05) while the young group showed no significant difference between AC and NAC. There was no significant group difference for within-trial $V_{UCM}$. Between-trial $V_{ORT}$ remained unchanged between groups and conditions. However, between-trial $V_{UCM}$ for the elderly group significantly decreased in AC as compared to NAC, along with no significant difference for the young group. For multi-finger synergy, there was no significant group difference of within-trial synergy. However, between-trial synergy for the elderly group significantly decreased in AC as compared to NAC (p < .05). Conclusion: Our results indicate that aging decreased consistency (i.e., ability to perform the task on a moment-to-moment basis) with an additional mechanical constraint. In addition, aging was associated with decreased multi-finger synergy on a trial-to-trial basis.

• Culinary science and hospitality research
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• v.19 no.1
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• pp.12-25
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• 2013

This study conducted an empirical analysis on the hypothesis of structural relationship that the resources of diversification foodservice corporations develop into resource sharing about creating synergy on the basis of resource based view. Based on the questionnaire answered by 237 foodservice employees over three years, this study examined its validity and reliability by using SPSS 16.0 and AMOS 5.0 for hypothesis. The result of study modelling were GFI=0.910, NFI=0.915, CFI=0.952, RMSEA=0.070 at the level of $x^2$=179.797(df=83, p<0.001). First, intangible resources 0.180(t=2.371, p<0.05), tangible resources 0.127(t=2.028, p<0.05) and human resources 0.263(t=2.542, p<0.05) of diversification foodservice corporations had positive effects on resource sharing. And resource sharing 0.264(t=3.158, p<0.001) had a positive effect on synergy. Also, between resource sharing and synergy identified moderating effects by synergy implementation cost.

• Proceedings of the Korean Society of Precision Engineering Conference
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• 2013.05a
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• pp.1651-1652
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• 2013

• Molecules and Cells
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• v.26 no.5
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• pp.462-467
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• 2008

TPA is known to cooperate with an activated Ras oncogene in the transformation of rodent fibroblasts, but the biochemical mechanisms responsible for this effect have not been established. In the present study we used c-fos promoter-luciferase constructs as reporters, in transient transfection assays, in NIH3T3 cells to assess the mechanism of this cooperation. We found a marked synergistic interaction between TPA and a transfected v-Ha-ras oncogene in the activation of c-fos promoter and SRE. SRE has binding sites for TCF and SRF. A dominant-negative Ras (ras-N17) inhibited the TPA-Ras synergy by blocking the PKC-MAPK-TCF pathway. Dominant-negative RhoA and Rac1 (but not Cdc42Hs) inhibited the TPA-Ras synergy by blocking the Ras-Rho-SRF signaling pathway. Constitutively active $PKC{\alpha}$ and $PKC{\varepsilon}$ showed synergy with v-Ras. These results suggest that the activation of two distinct pathways such as Ras-Raf-ERK-TCF pathway and Rho-SRF pathway are responsible for the induction of c-fos by TPA and Ras in mitogenic signaling pathways.

• The Transactions of the Korean Institute of Electrical Engineers P
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• v.59 no.2
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• pp.197-201
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• 2010

$SF_6$ gas would be used in power transformer, GIS (Gas insulated switchgear) and so on because of its electrically superior insulation and chemically stable structure. Recently, the reduction of $SF_6$ is required to avoid global warming and the researches on the dilution of $SF_6$ with other gases have been carried out. $SF_6$ mixture gases with $N_2$ and $C_xF_y$ have drawn attention to the synergy effect. However, in order to understand the mechanism of the synergy effect, it is important to analyze and evaluate properties of mixture gases quantitatively. In this paper, we investigated the mechanism of synergy effect from electron collision processes and electron energy distribution by solving Boltzmann equation with propagator method. Three kinds of gases for dilution of $SF_6$ ($SF_6/N_2$, $SF_6/CF$4 and $SF_6/C_4F_8$) are considered in this simulation. On the properties of $SF_6/N_2$ mixture gas, the variation of reduced electric field was shown highly within 0%~40% mixtures of $SF_6$. And the more low-level electron energy has been distributed, the higher insulation capability has appeared.