• Journal of Power Electronics
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• v.13 no.4
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• pp.569-583
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• 2013

In this study, the simultaneous use of a multi-level converter (MLC) as a DC-motor drive and as an active battery cell balancer is investigated. MLCs allow each battery cell in a battery pack to be independently switched on and off, thereby enabling the potential non-uniform use of battery cells. By exploiting this property and the brake regeneration phases in the drive cycle, MLCs can balance both the state of charge (SoC) and temperature differences between cells, which are two known causes of battery wear, even without reciprocating the coolant flow inside the pack. The optimal control policy (OP) that considers both battery pack temperature and SoC dynamics is studied in detail based on the assumption that information on the state of each cell, the schedule of reciprocating air flow and the future driving profile are perfectly known. Results show that OP provides significant reductions in temperature and in SoC deviations compared with the uniform use of all cells even with uni-directional coolant flow. Thus, reciprocating coolant flow is a redundant function for a MLC-based cell balancer. A specific contribution of this paper is the derivation of a state-space electro-thermal model of a battery submodule for both uni-directional and reciprocating coolant flows under the switching action of MLC, resulting in OP being derived by the solution of a convex optimization problem.

• Journal of Power Electronics
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• v.15 no.3
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• pp.775-785
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• 2015

Many equalization circuits have been proposed to improve pack performance and reduce imbalance. Although bidirectional equalization topologies are promising in these methods, pre-equalization global equalization strategy is lacking. This study proposes a novel state-of-charge (SoC) equalization algorithm for bidirectional equalizer based on particle swarm optimization (PSO), which is employed to find optimal equalization time and steps. The working principle of bidirectional equalization topologies is analyzed, and the reason behind the application of SoC as a balancing criterion is explained. To verify the performance of the proposed algorithm, a pack with 12 LiFePO4 batteries is applied in the experiment. Results show that the maximum SoC gap is within 2% after equalization, and the available pack capacity is enhanced by 13.2%. Furthermore, a comparison between previously used methods and the proposed PSO equalization algorithm is presented. Experimental tests are performed, and results show that the proposed PSO equalization algorithm requires fewer steps and is superior to traditional methods in terms of equalization time, energy loss, and balancing performance.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.11C
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• pp.1040-1045
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• 2002

This paper focuses on a hash-based, distributed Wet caching network that eliminates inter-cache communication. An agent program on cache servers, a mapping program on the DNS server, and other components comprised in a distributed Web caching network were modified and developed to implement a so-called "consistent" hashing. Also, a dynamic load balancing algorithm is proposed to address the load-balancing problem that is a key performance issue on distributed architectures. This algorithm effectively balances the load among cache servers by distributing the calculated amount of mapping items that have higher popularity than others. Therefore, this developed network can resolve the imbalanced load that is caused by a variable page popularity, a non-uniform distribution of a hash-based mapping, and a variation of cache servers.

• Journal of TMJ Balancing Medicine
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• v.9 no.1
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• pp.4-11
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• 2019

Objectives: Although intraoral balancing appliance therapy has been used effective to several diseases, verification studies through cerebral diseases are poorly reported so far. Thus we investigated the effect of tooth-cut induced dental malocclusion against mouse model of ischemic stroke. Methods: Tooth-cut and 90 min middle cerebral artery occlusion (MCAO) were loaded to C57BL/6 male mice, and total infarct area, neurological deficit scores (NDS), histological change of hippocampal region were observed. Production levels of reactive oxygen species (ROS) and inducible nitric oxide synthase (iNOS) in cerebral tissue were also measured. Results: The longer the tooth-cut period, the greater the area of cerebral infarction caused by MCAO, and NDS began to increase as the tooth was cut, and the results were more negative when MCAO was loaded. Histological change of hippocampal cells was significant when tooth-cut was maintained for 7 days. Those damages were thought to depend on the generation of ROS and iNOS in brain tissue. Conclusions: Since tooth-cut increased total area of cerebral infarction due to MCAO in mice, it is able to be confirmed that anomaly of the temporomandibular occlusion can affect neurological diseases.

• The Journal of Korean Institute of Communications and Information Sciences
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• v.27 no.5C
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• pp.422-434
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• 2002

We propose 3-layered hierarchical fiber-optic backbone transmission network composed of B-DCS, Backbone ring, Edge ring for efficient transmission of high capacity traffic and consider design method to ensure network survivability of each layer at affordable cost. Mathematical ring-construction cost minimization using MIP(Mixed Integer Programming) models results in NP-complete problem. So, it is hard to solve it within reasonable computing time. on a large-scale network. Therefore we develop heuristic algorithms solving WSCAP(Working and Spared Channel Assignment Problem) for B-DCS, MRLB(Multi-Ring Load Balancing) problem for Backbone ring, and ORLB(Overlayed Ring Load Balancing) problem for Edge ring and show their usefulness through case study.

• The KIPS Transactions:PartC
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• v.13C no.2 s.105
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• pp.219-226
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• 2006

The shortest path is only maintained during short time because network topology changes very frequently and each mobile nodes communicate each other by depending on battery in MANET(Mobile Ad-hoc Network). So many researches that are to overcome a limitation or consider a power have executed actively by many researcher. But these protocols are considered only one side of link stability or power consumption so we can make high of stability but power consumption isn't efficient. And also we can reduce power consumption of network but the protocol can't make power consumption of balancing. For that reason we suggest RBSSPR(Residual Battery Capacity and Signal Strength Based Power-aware Routing Protocol in MANET). The RBSSPR considers residual capacity of battery and signal strength so it keeps not only a load balancing but also minimizing of power consumption. The RBSSPR is based on AODV(Ad-hoc On-demand Distance Vector Routing). We use ns-2 for simulation. This simulation result shows that RBSSPR can extense lifetime of network through distribution of traffic that is centralized into special node and reducing of power consumption.

• Korean Journal of Applied Biomechanics
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• v.22 no.2
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• pp.173-181
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• 2012

The purpose of this study was to research on the movement of Fouette A La Second which was a type of turning movements on cheerleading. This research was conducted for helping cheerleaders to improve their overall skills. The three cheerleading national team members were participated in this research and the movements of Fouette A La Second were recorded with 6 digital motion master 60 video cameras, operating at a sampling frequency of 60 fields/sec. Six out of ten turning motion data were collected and analyzed with Kwon3D XP. The results were as follow: 1) The subject A's Releve motion was not executed precisely because of the COG's unstability. So she was required to improve the balancing ability. 2) The subject B could not execute the precise A La Second motion because of subject B's large hip angle. By tracing the projection of B's right toe on x-y plane, the subject made an elliptical orbit. Because B did not have a proper turning skills she needed to improve the muscle power and flexibility. She also needed to move quickly from Releve to Plie movement. 3) The subject C could not execute the Plie movement precisely, so she could not turn her body correctly around a certain spot. The subject C needed to decrease the knee angle at the Plie motion.

• Journal of Microbiology and Biotechnology
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• v.19 no.1
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• pp.23-36
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• 2009

In the present work, the metabolic network of primary metabolism of the slow-growing myxobacterium Sorangium cellulosum was reconstructed from the annotated genome sequence of the type strain So ce56. During growth on glucose as the carbon source and asparagine as the nitrogen source, So ce56 showed a very low growth rate of $0.23\;d^{-1}$, equivalent to a doubling time of 3 days. Based on a complete stoichiometric and isotopomer model of the central metabolism, $^{13}C$ metabolic flux analysis was carried out for growth with glucose as carbon and asparagine as nitrogen sources. Normalized to the uptake flux for glucose (100%), cells recruited glycolysis (51%) and the pentose phosphate pathway (48%) as major catabolic pathways. The Entner-Doudoroff pathway and glyoxylate shunt were not active. A high flux through the TCA cycle (118%) enabled a strong formation of ATP, but cells revealed a rather low yield for biomass. Inspection of fluxes linked to energy metabolism revealed that S. cellulosum utilized only 10% of the ATP formed for growth, whereas 90% is required for maintenance. This explains the apparent discrepancy between the relatively low biomass yield and the high flux through the energy-delivering TCA cycle. The total flux of NADPH supply (216%) was higher than the demand for anabolism (156%), indicating additional reactions for balancing of NADPH. The cells further exhibited a highly active metabolic cycle, interconverting $C_3$ and $C_4$ metabolites of glycolysis and the TCA cycle. The present work provides the first insight into fluxes of the primary metabolism of myxobacteria, especially for future investigation on the supply of cofactors, building blocks, and energy in myxobacteria, producing natural compounds of biotechnological interest.

• The Journal of Korean Academy of Prosthodontics
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• v.26 no.1
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• pp.153-169
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• 1988

There is a little scientific documentation reporting the stress, distribution to the edentulous mandible by different concepts of occlusal scheme. So, this study was to investigate the hypothesis that the magnitude and distribution of the occlusal stresses, transmitted through a mandibular complete denture base to the edentulous mandible, would be influenced by the lingualized occlusion. This investigation was performed to analyze the stresses induced in a three-dimensional photoelastic edentulous mandible, when a load is applied to the denture arranged into lingualized occlusion in centric relation, lateral and protrusive functional position. The mounted denture on a Dentatus Type ARO articulator was loaded in a pure vertical direction with 15kgs on the center of articulator in each case and the stresses were frozen into epoxy edentulous model at $127^{\circ}C$ in the stress freezing furnace. The stress-frozen epoxy models were sliced with diamond disc saw into 4mm thick. The slices were examined with a circular polariscope. The results were as follows: 1. In centric relation, the stresses were low at anteriors, and gradually increase to the premolar, molar area and highest at the first molar and gradually decrease from the second molar and lowest at the retromolar pad region. The lingual side showed higher stresses than labiobuccal side. 2. In lateral functional position, the working side showed higher stresses than the balancing side. In working side, the lingual side showed higher stresses than the buccal side and in balancing side, the buccal side showed higher stresses than the lingual side. 3. In protrusive position, stress distribution was symmetrical on the posteriors and the stresses were concentrated at the labial side of the anteriors.

• The KIPS Transactions:PartC
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• v.12C no.4 s.100
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• pp.543-550
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• 2005

Many routing algorithms, proposed for ad-hoc wireless networks, we based on source routing scheme and shortest path route has short lifetime especially in highly dense ad-hoc wireless networks. So some routing protocols such as SSA and ABR are considering the link stability and try finding more stable route. In this paper we propose a new routing algorithm considering utilization metric based on SSA routing algerian in Ad-Hoc networks. To reduce the bottleneck by specific metric of SSA, proposed scheme makes load balancing in networks by distributing the connections to several routes. For the evaluation of the performance we compare our scheme with existent routing protocol AODV and SSA. And the results, obtained using the ns-2 network simulation platform, show good performance that reduced the number of reconstructions remarkably by distributing the whole traffic to several routes when there are several stable routes.