• 제목/요약/키워드: Life Time value

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Analysis of Real-Time Estimation Method Based on Hidden Markov Models for Battery System States of Health

  • Piao, Changhao;Li, Zuncheng;Lu, Sheng;Jin, Zhekui;Cho, Chongdu
    • Journal of Power Electronics
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    • v.16 no.1
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    • pp.217-226
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    • 2016
  • A new method is proposed based on a hidden Markov model (HMM) to estimate and analyze battery states of health. Battery system health states are defined according to the relationship between internal resistance and lifetime of cells. The source data (terminal voltages and currents) can be obtained from vehicular battery models. A characteristic value extraction method is proposed for HMM. A recognition framework and testing datasets are built to test the estimation rates of different states. Test results show that the estimation rates achieved based on this method are above 90% under single conditions. The method achieves the same results under hybrid conditions. We can also use the HMMs that correspond to hybrid conditions to estimate the states under a single condition. Therefore, this method can achieve the purpose of the study in estimating battery life states. Only voltage and current are used in this method, thereby establishing its simplicity compared with other methods. The batteries can also be tested online, and the method can be used for online prediction.

A Heuristic Approach Solving for the Complex Design Process in the Quality Function Deployment

  • Park, Tae-Hyung;Cho, Moon-Soo
    • Journal of Korean Society for Quality Management
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    • v.30 no.4
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    • pp.137-153
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    • 2002
  • Viewed as a more systematic approach of creating high quality products and bringing them into market at a lower cost and in significantly less time, it attracts the attention of quality designers to quality function deployment (QFD) approach. In attempt to reduce the design cycle, the industry has responded with concurrent design effort. In a sense, concurrent engineering refers to the integration of various activities within the broad scope of the product life cycle [17]. Over the last ten years, much has been written about QFD but little has been available in terms of the underlying guide methodology. The methodology of QFD is quite simple and many will say that they have done it in the past but just have not formalized it into the form that this discipline requires. QFD ties the product, user, value, and manufacturing viewpoints together in a continuous process of defining the product design and manufacturing requirements. The value viewpoint recognizes the cost to obtain certain functionality, and the manufacturing viewpoint addresses conformance to requirements, but in a broader sense, the variability in production. In this paper, the QFD system acquisitions are described, and two heuristic approaches solving for the complex design process, especially the size reduction of design process and precedence-constrained relationship in QFD are proposed, and the empirical example is illustrated.

Toxin Produced by Colletotrichum falcatum Causing Red Rot of Sugarcane

  • Saikia, R.;Azad, P.;Arora, D.K.
    • Mycobiology
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    • v.32 no.4
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    • pp.149-154
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    • 2004
  • Toxin produced by Colletotrichum falcatum Went, the incitant of red rot of sugarcane was isolated, purified and assayed to determine host specificity and identify its chemical nature. The toxin was found to be not host specific as it inhibited germination of various seeds(gram, greengram, blackgram, pea, cowpea, rice and sugarcane) as well as different seedlings viz. tomato, coriander, pea and rice. The toxin consists of two distinct fraction-one fraction having $R_f$, value at 0.36 producing identical red rot lesion when inoculated at leaf midrib of sugarcane, and the other having $R_f$, value at 0.72 not showing any red rot lesion. Chromatogram of high performance liquid chromatography(HPLC) of the red rot lesion causing fraction showed a sharp peak at 1.62 min of retention time(RT), and spectral analysis indicated the presence of following chemical $CH_3$ - groups-C-H, C=O, C-N, $-CH_3,\;-CH_2$ -CH and molecular mass of the compound was 203. - ($M^+,\;C_{11}H_{11}N_2O_2$).

Neutronic analysis of control rod effect on safety parameters in Tehran Research Reactor

  • Torabi, Mina;Lashkari, A.;Masoudi, Seyed Farhad;Bagheri, Somayeh
    • Nuclear Engineering and Technology
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    • v.50 no.7
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    • pp.1017-1023
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    • 2018
  • The measurement and calculation of neutronic parameters in nuclear research reactors has an important influence on control and safety of the nuclear reactor. The power peaking factors, reactivity coefficients and kinetic parameters are the most important neutronic parameter for determining the state of the reactor. The position of the control shim safety rods in the core configuration affects these parameters. The main purpose of this work is to use the MTR_PC package to evaluate the effect of the partially insertion of the control rod on the neutronic parameters at the operating core of the Tehran Research Reactor. The simulation results show that by increasing the insertion of control rods (bank) in the core, the absolute values of power peaking factor, reactivity coefficients and effective delayed neutron fraction increased and only prompt neutron life time decreased. In addition, the results show that the changes of moderator temperature coefficients value versus the control rods positions are very significant. The average value of moderator temperature coefficients increase about 98% in the range of 0-70% insertion of control rods.

Research on Protection Method for Ground Electrode of DC Systems from Corrosion (직류 접지극의 전식보호 방법 연구)

  • Jeong, Woo-Yong;Kim, Hyosung
    • The Transactions of the Korean Institute of Power Electronics
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    • v.26 no.2
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    • pp.90-95
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    • 2021
  • In contrast to AC grounding systems, the ground electrode in DC systems continuously maintains positive or negative polarity. Ground electrodes with (+) polarity proceeds by oxidation reaction. Thus, the DC current should flow opposite to the polarity of the leakage current flowing through the (+) ground electrode by using a compensation electrode, and the current flowing through the (+) ground electrode can be 0A. However, according to protecting the (+) ground electrode, the compensation electrode corrodes and gets damaged. Thus, the (+) ground electrode must be protected from corrosion, and the service life of the compensation electrode must be extended. As an alternative, the average value of the current flowing through the compensation electrode should be equal with the value of the leakage current flowing through the (+) ground electrode by using the square waveform. Throughout the experiment, the degree of corrosion on the compensation electrode is analyzed by the frequency of the compensation electrode for a certain time. In the experiment, the frequencies of the square waveform are considered for 0.1, 1, 10, 20, 50, 100 Hz, and 1 kHz. Through experiments and analysis, the optimal frequency for reducing the electrolytic damage of the (+) electrode and compensation electrode in an LVDC grounding environment is determined.

Optimization of Pan Bread Prepared with Ramie Powder and Preservation of Optimized Pan Bread Treated by Gamma Irradiation during Storage

  • Lee, Hee-Jeong;Joo, Na-Mi
    • Preventive Nutrition and Food Science
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    • v.17 no.1
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    • pp.53-63
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    • 2012
  • This study was conducted to develop an optimal composite recipe for pan bread with ramie powder that has high sensory approval with all age groups and to estimate the DPPH radical scavenging activity and the pan bread shelf life after gamma irradiation. The sensory evaluation results showed significant differences in flavor (p<0.05), appearance (p<0.01), color (p<0.01), moistness (p<0.01), and overall quality (p<0.05) based on the amount of ramie powder added. As a result, the optimum formulations by numerical and graphical methods were calculated to be as follows: ramie powder 2.76 g (0.92%) and water 184.7 mL. Optimized pan bread with ramie powder and white pan bread were irradiated with gamma-rays at doses of 0, 10, 15, and 20 kGy. The total bacterial growth increased with the longer storage time and the least amount of ramie powder added. Consequently, these results suggest that the addition of ramie powder to pan bread provides added value to the bread in terms of increased shelf life.

Kinetic Study on the Enzymatic Production of D-Alanine from D-Aspartic Acid

  • Lee, Jae-Heung;Sung, Moon-Hee;Jeon, Yeong-Joong
    • Journal of Microbiology
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    • v.40 no.1
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    • pp.33-37
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    • 2002
  • An enzymatic reaction for the production of D-alanine from D-aspartic acid and pyruvate as substrates by a thermostable D-amino acid aminotransferase (D-AAT) was investigated at various conditions In the temperature range of 40-70$\^{C}$ and pH range of 6.0-9.5. The D-AAT was produced with recombinant E. coli BL21, which hosted the chimeric plasmid pTLK2 harboring the D-AAT from the novel thermophilic Bacillus sp. LK-2. The enzyme reaction was shown to follow the Ping Pong Bi Bi mechanism. The K$\_$m/ values for D-aspartic acid and pyruvate were 4.38 mar and 0.72 mM, respectively. It was observed that competitive inhibition by D-alanine, the product of this reaction, was evident with the inhibition constant K$\_$i/ value of 0.1 mM. A unique feature of this reaction scheme is that the decorboxylation of oxaloacetic acid, one of the products, spontaneously produces pyruvate. Therefore, only a catalytic amount of pyruvate is necessary for the enzyme conversion reaction to proceed. A typical time-course kinetic study skewed that D-alanine up to 88 mM could be produced from 100 mM of D-aspartic acid with a molar yield of 1.0.

Physicochemical and Sensory Characteristics of Kakdugi Prepared with Red Paprika Powder (홍파프리카로 담근 깍두기의 이화학적.관능적 특성)

  • 이지숙;이영주;김미리
    • Journal of the East Asian Society of Dietary Life
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    • v.13 no.1
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    • pp.64-71
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    • 2003
  • Physicochemical and sensory characteristics of Kakdugi substituted red pepper powder with red paprika powder during fermentation at 1$0^{\circ}C$ were compared with those of the control. The fermentation patterns of two Kimchies were similar. While the pH and the acidity of the control were 3.88 and 0.691%(as lactic acid), respectively, those of paprika, 3.85 and 0.690%(as lactic acid), respectively on the 10th day of fermentation, which is the optimal ripe time. Reducing sugar content and Lactobacilli number of paprika Kakdugi were higher than those of the control. The hardness and fracturability of Kakdugi radish were not significantly different from those of the control during fermentation. The Hunter color L, a and b values of both Kakdugies increased gradually until l0th day and then decreased. The a and ASTA value of paprika Kakdugi was higher than that of control, which is consistent with the results of sensory evaluation. Capsaicin and dihydrocapsaicin analyzed by HPLC were not detected in paprika Kakdugi. Sensory evaluation (unstructured scale, 10 points) showed the score of hot taste f3r paprika Kakdugi was lower than that of the control(p<0.05), whereas the score of over-all acceptabillity for paprika Kakdugi(8.0) was higher than those of control(6.1).

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Fatigue Life Prediction of Non-Load-Carrying Cruciform Welded Joint using Master S-N Curve based on Structural Stress Approach (구조응력기반 마스터 피로 선도를 이용한 하중 비전달형 십자 필렛 용접조인트의 피로예측)

  • Kwak, Si-Young
    • Journal of Welding and Joining
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    • v.33 no.6
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    • pp.49-54
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    • 2015
  • Welding process is of importance to assemble products or structures, but also the process is structural weakness due to stress concentration in welding joint. The fatigue design of welded joint requires time & labor consuming fatigue test because the fatigue life is various according to the depth of joint, joint type and load type etc. In fatigue design codes, they guide to classify welding joints with their shape( BS7608, IIW Documents) and provide fatigue assessment information. In terms of numerical method for fatigue analysis, it is also difficult to decide the stress peak in joint because of mesh sensitivity which means that stress value is varies with element type or size on stress concentration zone. Hot-spot method is used generally, but Battelle of United States proposed Master S-N Curve based on structural stresses converted by mechanical equilibrium theory. In this research, we extracted master S-N curve from Battelle's fatigue test DB including test data of various welding joints to apply on Non-Load-Carrying cruciform Joint. Comparing fatigue results between the case of using normal stress and case of structural stress cor the cruciform Joint, The suggested Battelle method showed successive results.

Ageing Behavior of Beeswax Coated Hanji(I) - Thermal Ageing Test of Beeswax Coated Hanji - (밀랍지의 열화 거동 (제1보) - 열에 의한 밀랍지의 열화 -)

  • Kim, Kang-Jae;Eom, Tae-Jin
    • Journal of Korea Technical Association of The Pulp and Paper Industry
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    • v.42 no.2
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    • pp.46-52
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    • 2010
  • The annals of Joseon Dynasty has been known as one of the UNESCO's Memory of the World Heritage. The annals of Joseon Dynasty composed with two kind of books, wax coated book and non coated book. Especially the waxed book have been severely damaged by various reason. For the safety preservation of the annals of Joseon Dynasty waxed book, the thermal ageing mechanism of beeswax coated Hanji paper has been evaluated. The weight loss of waxed Hanji were rapidly increased until 30 days in three temperatures(105, 120 & $150^{\circ}C$) and stabilized after 30 days. The acid value and relative intensity of carbonyl groups in beeswax were increased with strong conditions. This means that the deterioration of beeswax should be progressed with oxidizing reaction. The physical strength and the crystallinity of dewaxed Hanji were decreased with ageing time.