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In this paper, the State of Charge (SOC) estimation algorithm is proposed using the Direct Current Internal Resistance (DCIR) repetitive calculation, which reflects the renewed Open Circuit Voltage (OCV) in real-time by using the measured DCIR through the constant current injection method. Therefore, it is possible to improve the estimation error because there is no integration error and reset interval. Finally, the performance of the proposed method is evaluated by comparing with the estimated SOC result using the Coulomb-Counting method under the various C-rates experimental conditions. Also, a State of Health (SOH) estimation method using measured DCIR and Extended Kalman filter (EKF) is proposed. The accuracy of estimation method is evaluated by MATLAB simulation results.

This paper carries out a series of the analysis of the power system using gallium nitride (GaN) FET which has a wide band gap (WBG) characteristics comparing to the conventional silicon (Si) MOSFET-used power system. At first, for the comparison of each semiconductor device, the switching-transient parameter is quantitatively extracted from the released information of GaN FET. And GaN FET model which reflect this dynamic property is configured. By using this model, the performance of GaN FET is analyzed comparing to Si MOSFET. As a result, GaN FET power system, designed by the optimal point suggested in this paper, can reduce the loss by 25.5% and the volume by 78.6% of major components comparing conventional Si MOSFET power system.

This paper presents a Coulomb counting algorithm using the estimating OCV through a short rest time, such as the traffic signal time. Proposed algorithm could enhance the SOC estimating accuracy through the frequent SOC reset using a greatly short rest time, even though SOC reset error occurs. Also algorithm is implemented for a highly accurate SOC estimation by a SOC error prediction, an improvement of required rest time for SOC reset and a compensation of SOC reset error. The proposed algorithm is verified by experiment using the UDDS profile and it is verified that it could improve the SOC estimation accuracy up to 2.07%.

Response Surface Methodology (RSM) was used to investigate optimal refolding conditions of Pseudomonas fluorescens lipase which was expressed as inclusion body in E. coli. Three interacting factors, protein concentration, pH and guanidine hydrochloride (GdnHCl) concentration were selected as the variables of RSM. The protein concentration did not affect the refolding yield within the selected range (50-340 micrograms ml-1) at low temperatures of 4 and -15 degrees C, but it was a critical factor at 25 degrees C and refolding yield significantly decreased with increasing protein concentration. The pH and GdnHCl were significant factors in all experimental conditions. But there was no trends of optimal pH depending on temperature and additives, just showing the optimum at neutral pH. Glycerol shifted optimal GdnHCl concentration to higher side, while arginine to lower side. Therefore, it was concluded that glycerol and arginine deprives and supplements GdnHCl, respectively. In this study, RSM made it possible to investigate successfully the optimal conditions of in vitro refolding and to elucidate interactions between refolding factors with a minimum number of experiments. Under the optimal condition determined by RSM, approximately 90% refolding yield was obtained and it was a 30% increase over the conventional method.

In this paper, a single-switch ZVZCS quasi-resonant CLL isolated dc-dc converter for the low-power 32" LDC TV less than 100 W is proposed. The proposed converter achieves soft switching of the switch at turn on and turn off without additional active switches and components as well as eliminates the switching losses of the rectifying diode. The advantage of the proposed converter is that the variation of the switching frequency is less than about 10 kHz when loads change from 30% to 100%. EMI performance can be improved by soft switching.

This paper carries out feasibility study of DC home appliance in appropriate of DC power supply system. For this purpose, the difference of structure and safety between AC and DC home appliance is comparatively analyzed, and the countermeasures against predicted problems are suggested in advance. The power simulator of general specifications is designed for comprehensive evaluation. Under this experimental test-bed, the possibility of DC home appliance with these countermeasures is verified.

This paper performs analysis and verification of active inrush current limiter (AICL) using the MOSFET for high-voltage DC power supply. To active this, the performance characteristic of AICL is analyzed comparatively with inrush current limiters using inductor, NTC thermistor, and relay, which have been used to protect the devices. And utilized of AICL when is applied to high-voltage DC power supply is considered. In addition, a study on the relationship between the strength of a limited current, settling time and parameter of devices, which are organized AICL is performed. To verify effectiveness of AICL experiment is carried out using actual parameters. Through this study, utilization and reliability of AICL for high-voltage DC power supply is analyzed and evaluated theoretically and experimentally.

Zinc sulfide [ZnS] thin films were deposited on glass substrates using radio frequency magnetron sputtering. The substrate temperature was varied in the range of 100°C to 400°C. The structural and optical properties of ZnS thin films were characterized with X-ray diffraction [XRD], field emission scanning electron microscopy [FESEM], energy dispersive analysis of X-rays and UV-visible transmission spectra. The XRD analyses indicate that ZnS films have zinc blende structures with (111) preferential orientation, whereas the diffraction patterns sharpen with the increase in substrate temperatures. The FESEM data also reveal that the films have nano-size grains with a grain size of approximately 69 nm. The films grown at 350°C exhibit a relatively high transmittance of 80% in the visible region, with an energy band gap of 3.79 eV. These results show that ZnS films are suitable for use as the buffer layer of the Cu(In, Ga)Se2 solar cells.

This paper analyzes AC and DC supplied home appliances comparatively for check of existing safety standards as DC power supply system serviced at home. Firstly, DC appliance model that is devised to suit dc distribution system by this paper is compared with AC appliance for analysis of the difference. Secondly, international safety standards of AC appliances are analyzed. In conclusion, for DC safety standards setup, this paper guides intelligence of what kinds of safety standards should be complemented for eliminating risk caused by distribution system change in many standards.

Pseudomonas fluorescens is an opportunistic indoor pathogen that can cause severe airway proinflammatory responses. Pulmonary epithelium, like other mucosal epithelial linings of the body, constitutes the first line of defense against airway microbial pathogens. Mucosal epithelial cells can be a sentinel of pathogenic bacteria via stimulation of specific cell surface receptors, including the epidermal growth factor receptor (EGFR) and Toll-like receptor (TLR). This study addressed the involvement of EGFR in airway epithelial pathogenesis by P. fluorescens . Human A549 pneumocytes showed prolonged production of proinflammatory interleukin-8 (IL-8) in response to infection with P. fluorescens , which was via the nuclear factor-kappa B (NF-κB) signaling pathway. Production of proinflammatory cytokine IL-8 was not mediated by P. fluorescens lipopolysaccharide, a representative TLR4 agonist, but was mediated through EGFR-linked signals activated by the opportunistic bacteria. Moreover, EGFR signals were involved in NF-κB signal-mediated production of proinflammatory cytokines. Along with persistent NF-κB activation, P. fluorescens enhanced the EGFR phosphorylation and subsequent activation of downstream mediators, including protein kinase B or extracellular-signal-regulated kinases 1/2. Blocking of EGFR-linked signals increased epithelial susceptibility to pathogen-induced epithelial cell death, suggesting protective roles of EGFR signals. Thus, airway epithelial exposure to P. fluorescens can trigger antiapoptotic responses via EGFR and proinflammatory responses via TLR4-independent NF-κB signaling pathway in human pneumocytes.

Background ATP binding cassette (ABC) transporter secretes the protein through inner and outer membranes simultaneously in gram negative bacteria. Thermostable lipase (TliA) of Pseudomonas fluorescens SIK W1 is secreted through the ABC transporter. TliA has four glycine-rich repeats (GGXGXD) in its C-terminus, which appear in many ABC transporter-secreted proteins. From a homology model of TliA derived from the structure of P. aeruginosa alkaline protease (AprA), lipase ABC transporter domains (LARDs) were designed for the secretion of fusion proteins. Results The LARDs included four glycine-rich repeats comprising a β-roll structure, and were added to the C-terminus of test proteins. Either Pro-Gly linker or Factor Xa site was added between fusion proteins and LARDs. We attached different length of LARDs such as LARD0, LARD1 or whole TliA (the longest LARD) to three types of proteins; green fluorescent protein (GFP), epidermal growth factor (EGF) and cytoplasmic transduction peptide (CTP). These fusion proteins were expressed in Escherichia coli together with ABC transporter of either P. fluorescens or Erwinia chrysanthemi. Export of fusion proteins with the whole TliA through the ABC transporter was evident on the basis of lipase enzymatic activity. Upon supplementation of E. coli with ABC transporter, GFP-LARDs and EGF-LARDs were excreted into the culture supernatant. Conclusion The LARDs or whole TliA were attached to C-termini of model proteins and enabled the export of the model proteins such as GFP and EGF in E. coli supplemented with ABC transporter. These results open the possibility for the extracellular production of recombinant proteins in Pseudomonas using LARDs or TliA as a C-terminal signal sequence.

The ABC transporter (TliDEF) from Pseudomonas fluorescens SIK W1, which mediated the secretion of a thermostable lipase (TliA) into the extracellular space in Escherichia coli , was engineered using directed evolution (error-prone PCR) to improve its secretion efficiency. TliD mutants with increased secretion efficiency were identified by coexpressing the mutated tliD library with the wild-type tliA lipase in E. coli and by screening the library with a tributyrin-emulsified indicator plate assay and a microtiter plate-based assay. Four selected mutants from one round of error-prone PCR mutagenesis, T6, T8, T24, and T35, showed 3.2-, 2.6-, 2.9-, and 3.0-fold increases in the level of secretion of TliA lipase, respectively, but had almost the same level of expression of TliD in the membrane as the strain with the wild-type TliDEF transporter. These results indicated that the improved secretion of TliA lipase was mediated by the transporter mutations. Each mutant had a single amino acid change in the predicted cytoplasmic regions in the membrane domain of TliD, implying that the corresponding region of TliD was important for the improved and successful secretion of the target protein. We therefore concluded that the efficiency of secretion of a heterologous protein in E. coli can be enhanced by in vitro engineering of the ABC transporter.

Although chronic exposure to alcohol or its contaminants is the main carcinogenic risk factor in the high prevalence of hepatic cancers, information on the mutagenicity of Soju alcoholic spirits is limited. Presently, the mutagenicity of Soju was tested using the Ames test. Evaporation residues of 11 common brands of Soju were examined and four of the 11 brands displayed a mutagenic response in the TA98-based Ames test without S9 liver extract. Moreover, among these positive samples, two had mutagenic activity in both TA98- and TA100-based Ames tests with S9 liver extract. Some samples of Ames test-positivity also contained N-nitrosodimethylamine or N-acetoxy-2-acetylaminofluorene, implicating potential etiologic factors for the Ames test.

There are three major secretion pathways in gram-negative bacteria (57). The majority of the exoproteins are secreted via a two-step mechanism including a stopover in the periplasm (23). These proteins are translocated across the inner membrane in a signal sequence-dependent general export pathway (45). The subsequent translocation across the outer membrane requires 12 to 14 helper proteins (4, 23, 46). The second pathway used by several bacterial pathogens involves a transporter consisting of more than 20 secretion proteins (41). The protein is secreted through the inner and outer membranes simultaneously, bypassing the periplasm, and the secretion signals are located within 50 to 100 N-terminal residues (43). The last is an ATP-binding cassette (ABC) pathway, which also bypasses the periplasm (19). The protein is synthesized without an N-terminal signal sequence, and its secretion across two membranes involves three specific envelope proteins, ABC protein, membrane fusion protein and outer membrane protein. The secreted protein contains a C-terminal targeting signal containing several repeats of the consensus sequence GGXGXD (17, 22, 56) and an amphipathic α-helix (35, 50, 56). Lipases of the Pseudomonas species are secreted by at least two different pathways (31). The two-step pathway, which requires at least 12 xcp gene products, is used by the signal sequence-containing lipases of P. aeruginosa (55) and P. glumae (25). These lipases also need molecular chaperones, which are located immediately downstream of the lipase structural genes of P. cepacia (33), P. glumae (24), and P. aeruginosa (13, 29, 30, 59). The lipase of P. fluorescens B52 was reported to be secreted by the ABC pathway mediated by the ABC transporter of P. aeruginosa alkaline protease (18), although the structural gene of the ABC transporter in P. fluorescens was not identified. P. fluorescens SIK W1, a psychrotrophic bacterium, was found to secrete a thermostable lipase (7). We cloned this thermostable lipase (14) and expressed it in Escherichia coli, but it accumulated as inactive inclusion bodies in the cell (15). Sequence analysis showed that the lipase contained a C-terminal targeting signal sequence instead of an N-terminal signal sequence. Accordingly, the ABC transporter was assumed to be present in P. fluorescens SIK W1 because there is a specific ABC transporter for each protein secreted by the ABC pathway. Therefore, we searched for the ABC transporter gene in P. fluorescens SIK W1 and identified three components of the ABC transporter upstream of the lipase gene. In addition, the protease and protease inhibitor were located upstream of the three components. The ABC transporter of P. fluorescens was found to show temperature dependency in its secretory function when expressed in E. coli, and this suggested why P. fluorescens produces the lipase optimally at low temperature. There has been no report on the ABC transporter specific to lipase except in the Serratia marcescens Lip system (3), which is located separately from the lipase gene on the chromosome and secretes protease, lipase, and S-layer protein (34). In this paper, we report a new ABC transporter which is not only functionally specific for lipase but also structurally organized with the lipase gene as an operon on the chromosome.

Background TliA is a thermostable lipase secreted by the type 1 secretion system (T1SS) of Pseudomonas fluorescens. The secretion is promoted by its secretion/chaperone domain located near the C-terminus, which is composed mainly of four Repeat-in-Toxin (RTX) repeats. In order to identify the minimal region of TliA responsible for its secretion, five different copies of the secretion/chaperone domain, each involving truncated N-terminal residues and a common C-terminus, were acquired and named as lipase ABC transporter recognition domains (LARDs). Each LARD was fused to epidermal growth factor (EGF) or green fluorescent protein (GFP), and the secretion of EGF-LARD or GFP-LARD fusion proteins was assessed in Escherichia coli with ABC transporter. Results Among the fusion proteins, GFP or EGF with 105-residue LARD3 was most efficiently secreted. In addition, GFP-LARD3 emitted wild type GFP fluorescence. Structurally, LARD3 had the 4 RTX repeats exposed at the N-terminus, while other LARDs had additional residues prior to them or missed some of the RTX repeats. LARD3 was both necessary and sufficient for efficient secretion and maintenance of GFP fluorescence in E. coli, which was also confirmed in P. fluorescens and P. fluorescens ▵tliA, a knock-out mutant of tliA. Conclusion LARD3 was a potent secretion signal in T1SS for its fusion flanking RTX motif, which enhanced secretion and preserved the fluorescence of GFP. LARD3-mediated secretion in E. coli or P. fluorescens will enable the development of enhanced protein manufacturing factory and recombinant microbe secreting protein of interest in situ.