A Novel Method for Lithium-ion Battery Remaining Useful Life Prediction Using Time Window and Gradient Boosting Decision Trees

Zhiyong Zheng,Jun Peng,Kunyuan Deng,Kai Gao,Heng Li,Bin Chen,Yingze Yang,Zhiwu Huang 전력전자학회 2019 ICPE(ISPE)논문집 Vol.2019 No.5

Lithium-ion battery remaining useful life (RUL) is a key parameter on battery management system. Many machine learning methods are applied to RUL predictions, but they generally suffer from two limitations: (i) the extracted features fail to reflect the information hidden in the historical degradation status, and (ii) the accuracy cannot be guaranteed in the evaluation of battery degradation due to the non-linearity. In this paper, a new prediction method is proposed combining the time window (TW) and Gradient Boosting Decision Trees (GBDT). First, the energy (VCE) and the fluctuation index (VFI) of voltage signal are verified and selected as features. Then, a TW based feature extraction method is designed to extract features from the historical discharge process. After that, GBDT is adopted to model the relation of features and RUL. The proposed method is implemented on a recognized battery degradation dataset, and the advantages in accuracy are proven.

Purification and characterization of a novel immunomodulatory hexapeptide from alcalase hydrolysate of ultramicro-pretreated silkworm (Bombyx mori) pupa protein

Zhiyong Li,Shan Zhao,Xiang-Dong XIN,Bei Zhang,Attaribo Thomas,Asakiya Charles,Kwang Sik Lee,진병래,Zhong-Zheng Gui 한국응용곤충학회 2019 Journal of Asia-Pacific Entomology Vol.22 No.3

Silkworm (Bombyx mori) pupa protein is one potential source of insect protein for use in food. Immunomodulatory peptides are specific protein fragments that can positively influence human health. Here, we purified a novel immunomodulatory hexapeptide from the alcalase hydrolysate of ultramicro-pretreated silkworm pupa proteinusing Sephadex gel filtration chromatography and reverse-phase high-performance liquid chromatography (RP-HPLC). The peptide sequence was determined by liquid chromatography–electrospray ionization– tandem mass spectrometry (LC-ESI-MS/MS). The results showed that the molecular mass of the purified peptide was 656.17 Da, and the amino acid sequence was Pro-Asn-Pro-Asn-Thr-Asn (PNPNTN). Splenocyte proliferation was 87.35% in the presence of 100 μg/ml of purified peptide. The splenocyte proliferation could be promoted upto 248.4% at 100 μg/ml of PNPNTN after induction by Concanavalin A (Con A). PNPNTN was stable in the presence of the gastrointestinal proteases pepsin and trypsin and at temperatures up to120°C. Taken together, these results show that this novel immunomodulatory hexapeptide from silkworm pupae has potential therapeutic value as an immunomodulatory component of functional food.

Effects of manufacturing process and surface treatments on mechanical properties of PLA/SCF composites using extrusion printing

Zhiyong Ma,Zheng Qian,Jiabin Cai 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.5

Short carbon fiber (SCF) reinforced polylactic acid (PLA) composites were fabricated by extrusion printing, and the effects of process parameters and surface treatments on the mechanical properties of composites were studied. Based on the rheological properties of composites and the extrusion process simulation, pure PLA specimens and PLA/SCF specimens were manufactured under different printing parameters. Three kinds of surface treatment were adopted to improve the mechanical properties. The experimental results show that SCF can effectively improve the tensile strength and bending strength, but the compressive strength decreased. The specimen had the best mechanical properties when the layer height was 0.1 mm and the nozzle diameter was 0.6 mm. The mechanical properties can be further improved by coupling agent coating method, and the compressive strength was even higher than that of pure PLA specimen. The research in this paper can provide a reference for the fabrication of thermoplastic composites with excellent mechanical properties by extrusion printing.

Quantile inference for moderate deviations from a unit root model with infinite variance

Zhiyong Zhou,Zheng-Yan Lin 한국통계학회 2015 Journal of the Korean Statistical Society Vol.44 No.2

The limit distribution of the quantile estimate for the moderate deviations from a unit root model with possibly infinite variance errors is derived. Both the mildly integrated case and the mildly explosive case are investigated. Quicker convergence rates than the ordinary least squares estimation are gained. Numerical simulations are conducted to illustrate the performance of our estimation procedure.

Influence of Sodium Chloride on Thermal Denaturation of a High-Salt-Tolerant Neutral Protease from Aspergillus oryzae

Dong Wang,Zhiyong Zheng,Jie Feng,Xiao-Bei Zhan,Li-Min Zhang,Jian-Rong Wu,Chi-Chung Lin,Li Zhu 한국식품과학회 2013 Food Science and Biotechnology Vol.22 No.5

The temperature and pH stability of proteases have been extensively investigated. A neutral protease produced by Aspergillus oryzae was thermodynamically characterized at high-salt environment. When the protease was tested at 24% NaCl and 60oC, its half-life was increased to 30.0 min, 111% longer than that of control. Its Gibbs free energy and activation energy for denaturation in high NaCl concentration solutions were higher than in low salt solutions and increased by 2.1 and 4.75 kJ/mol,respectively. The protease exhibited higher thermal stability in higher salt conditions. This feature is beneficial to soybean sauce fermentation by enhancing the protease performance and taste of the product. Analysis by farultraviolet circular dichroism (far-UV CD) spectroscopy revealed that α-helix conformation in the protease increased from 3.2 to 31.7%, respectively, when the NaCl concentration increased from 0 to 18%, in agreement with the results deduced by thermodynamic calculations.

Effect of Co Doping on the Elastocaloric Effect of Ni-Mn-Ga-Co Alloy

Haixu Qin,Youping Zheng,Liu Yang,Sibo Sun,Zhiyong Gao 한국자기학회 2023 Journal of Magnetics Vol.28 No.3

Large latent heat is produced in the stress-induced martensitic phase transition process of Ni-Mn-Ca-based materials, i.e., elastocaloric effect. That makes such materials show tremendous potential for solid-state refrigeration which is identified as one of the most promising non-vapor-compression cooling devices. However, the still low refrigeration ability of these materials restricts further commercially promoting of solid-state refrigeration. In this work, we adjusted the Co content to regulate the elastocaloric effect for the Ni51.5Mn25Ga23Co0.5. According to the results, the transformation strain and ratio of loading stress/transformation temperature (dσ/ dT) were increased by replacing the Ni atoms with a little more Co, leading to an improvement of the stressinduced transformation entropy-change ΔSσ. As a result, a huge ΔSσ of 45.0 JKg-1K-1 is achieved in Ni50Mn25- Ga23Co1 alloy.

Enhanced Curdlan Production in Agrobacterium sp. ATCC 31749 by Addition of Low-polyphosphates

Lijun Yu,Jianrong Wu,Jia Liu,Xiaobei Zhan,Zhiyong Zheng,Chi Chung Lin 한국생물공학회 2011 Biotechnology and Bioprocess Engineering Vol.16 No.1

A large amount of adenosine triphosphate with high energy phosphate bonds is required for uridine triphosphate regeneration during curdlan biosynthesis by Agrobacterium sp. ATCC 31749. To supply high energy for curdlan synthesis, three low-polyphosphates (Na_4P_2O_7,Na_5P_3O_10, and (NaPO_3)_6) with higher energy phosphate bonds were employed to substitute for KH_2PO_4-K_2HPO_4in fermentation medium. Two genes encoding the polyphosphate metabolizing enzymes, polyphosphate kinase and exopolyphosphatase, were amplified and showed 95%homology to those in Agrobacterium sp. C58 by sequence analysis. The curdlan yields were enhanced by 23 and 134% when phosphate concentrations 0.024 mol/L of Na_5P_3O_10 and 0.048 mol/L of (NaPO_3)_6 respectively, were added in the medium. The maximum curdlan yield of 30 ±1.02 g/L was obtained with the addition of 0.048 mol/L of (NaPO_3)_6 with 5 g/L CaCO_3 in the medium. When CaCO_3 was removed from the culture and the three lowpolyphosphates were added, the pH and biomass yield dropped remarkably and little or no curdlan was produced. The culture containing 0.048 mol/L of (NaPO_3)_6 was mixed with KH_2PO_4-K_2HPO_4 and CaCO_3 in the medium,but showed no effect on curdlan production. However,curdlan yield was improved by 49 ~ 60% when CaCO_3was removed from the medium and KH_2PO_4-K_2HPO_4acted as a buffer. It appears that the positive effect of (NaPO_3)_6 on curdlan production required the buffering capacity of CaCO_3 and the absence of KH_2PO_4-K_2HPO_4competing as a phosphate supplier.

Purification and Characterization of a New Endo-β-1,3-glucanase Exhibiting a High Specificity for Curdlan for Production of β-1,3-Glucan Oligosaccharides

Jing Li,Li Zhu,Xiao-Bei Zhan,Min Xu,Chi Chung Lin,Zhiyong Zheng,Wei-Jiang Li 한국식품과학회 2014 Food Science and Biotechnology Vol.23 No.3

Endo-β-1,3-glucanase (Endo23) was purifiedfrom a Trichoderma reesei GIMCC 3.498 fermentationbroth using anion exchange and 2-stage size exclusionchromatography. Purification of 44.5× and a 12% recoveryyield of enzyme activity were achieved. The Mw andisoelectric point were estimated to be 24 kDa and 3.85using SDS-PAGE and IEF, respectively. The highestsubstrate specificity was observed for water-insoluble curdlan. The optimal conditions for hydrolyzing curdlan were pH5.0 and 50oC. The main hydrolytic products were glucobioseand glucotriose. Minor amounts of glucose and glucotetraosewere detected. Hg2+, Fe2+, Fe3+, and Sn2+ inhibited thehydrolysis activity of Endo23 at 5 and 50 mM. K+ slightlypromoted Endo23 activity. Endo23 belongs to the categoryEC3.2.1.39. The peptide sequences of Endo23 showedidentity with conserved sequences that typically exist in β-1,3-glucanases of the glycoside hydrolase family. TheEndo23 sequence was partially similar to a hypotheticallignocellulase from Penicillium oxalicum 114-2.

Improvement of ATP regeneration efficiency and operation stability in porcine interferon-α production by Pichia pastoris under lower induction temperature

Minjie Gao,Zhongping Shi,Shijuan Dong,Ruisong Yu,Jianrong Wu,Zhiyong Zheng,Xiaobei Zhan 한국화학공학회 2011 Korean Journal of Chemical Engineering Vol.28 No.6

The performance of traditional heterologous protein production by Pichia pastoris with methanol induction at 30 ℃ is poor, characterized by low ATP regeneration rate and weak operation stability. A low temperature induction strategy at 20 ℃ was thus adopted for efficient porcine interferon-α production in a 10 L fermentor. With the strategy,maximal methanol tolerance level could reach about 40 g/L to effectively deal with methanol concentration variations,so that the complicated on-line methanol measurement system could be eliminated. Moreover, metabolic analysis based on multiple state-variables measurements indicated that pIFN-α antiviral activity enhancement profited from the formation of an efficient ATP regeneration system at 20℃ induction. Compared to the induction strategy at 30 ℃, the proposed strategy increased the ATP regeneration rate by 49-66%, the maximal p_IFN-α antiviral activity was enhanced about 20-fold and reached a higher level of 1.5×10^6 IU/mL.

Security Analysis of the PHOTON Lightweight Cryptosystem in the Wireless Body Area Network

( Wei Li ),( Linfeng Liao ),( Dawu Gu ),( Chenyu Ge ),( Zhiyong Gao ),( Zhihong Zhou ),( Zheng Guo ),( Ya Liu ),( Zhiqiang Liu ) 한국인터넷정보학회 2018 KSII Transactions on Internet and Information Syst Vol.12 No.1

With the advancement and deployment of wireless communication techniques, wireless body area network (WBAN) has emerged as a promising approach for e-healthcare that collects the data of vital body parameters and movements for sensing and communicating wearable or implantable healthful related information. In order to avoid any possible rancorous attacks and resource abuse, employing lightweight ciphers is most effective to implement encryption, decryption, message authentication and digital signature for security of WBAN. As a typical lightweight cryptosystem with an extended sponge function framework, the PHOTON family is flexible to provide security for the RFID and other highly-constrained devices. In this paper, we propose a differential fault analysis to break three flavors of the PHOTON family successfully. The mathematical analysis and simulating experimental results show that 33, 69 and 86 random faults in average are required to recover each message input for PHOTON-80 /20/16, PHOTON-160/36/36 and PHOTON-224/32/32, respectively. It is the first result of breaking PHOTON with the differential fault analysis. It provides a new reference for the security analysis of the same structure of the lightweight hash functions in the WBAN.