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The self-organizing worm algorithm

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Journal of Systems Engineering and Electronics 2007年第3期18卷 650-654页

作者： Zheng Gaofei wang xiufeng Zhang Yanli Dept. of Mechanics Tianjin Polytechnic Univ. Tianjin 300160 P. R. China Information Technology Science Coll. Nankai Univ. Tianjin 300071 P. R. China Information & Communitiaon of Engineering School Tianjin Polytechnic Univ. Tianjin 300160 P. R. China

A new multi-modal optimization algorithm called the self-organizing worm algorithm （SOWA） is presented for optimization of multi-modal functions. The main idea of this algorithm can be described as follows： disperse some worms equably in the domain; the worms exchange the information each other and creep toward the nearest high point; at last they will stop on the nearest high point. All peaks of multi-modal function can be found rapidly through studying and chasing among the worms. In contrast with the classical multi-modal optimization algorithms, SOWA is provided with a simple calculation, strong convergence, high precision, and does not need any prior knowledge. Several simulation experiments for SOWA are performed, and the complexity of SOWA is analyzed amply. The results show that SOWA is very effective in optimization of multi-modal functions.

关键词： control theory, multi-modal optimization algorithm, self-organizing worm algorithm unit

Grinding Burn Detection Based on Cross Wavelet and Wavelet Coherence Analysis by Acoustic Emission Signal

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Chinese Journal of Mechanical Engineering 2019年第4期32卷 94-103页

作者： Zheyu Gao Jing Lin xiufeng wang Yuhe Liao Shaanxi Key Laboratory of Mechanical Product Quality Assurance and Diagnostics Xi'an Jiaotong University Xi'an 710049China School of Reliability and Systems Engineering Beihang University Beijing 100191 China

Grinding burn monitoring is of great importance to guarantee the surface integrity of the workpiece. Existing methods monitor overall signal variation. However, the signals produced by metal burn are always weak. Therefore, the detection rate of grinding burn still needs to be improved. The paper presents a novel grinding burn detection method basing on acoustic emission(AE) signals. It is achieved by establishing the coherence relationship of pure metal burn and grinding burn signals. Firstly, laser and grinding experiments were carried out to produce pure metal burn signals and grinding burn signals. No-burn and burn surfaces were generated and AE signals were captured separately. Then, the cross wavelet transform(XWT) and wavelet coherence(WTC) were applied to reveal the coherence relationship of the pure metal burn signal and grinding burn signal. The methods can reduce unwanted AE sources and background noise. Novel parameters based on XWT and WTC are proposed to quantify the degree of coherence and monitor the grinding burn. The grinding burn signals were recognized successfully by the proposed indexes under same grinding condition.

关键词： Grinding burn Cross wavelet transform Wavelet coherence Acoustic emission

Flexible Time Domain Averaging Technique

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Chinese Journal of Mechanical Engineering 2013年第5期26卷 1022-1030页

作者： ZHAO Ming LIN Jing LEI Yaguo wang xiufeng School of Mechanical Engineering Xi’an Jiaotong University State Key Laboratory for Manufacturing Systems Engineering Xi’an Jiaotong University Shaanxi Key Laboratory of Product Quality Assurance & Diagnosis

Time domain averaging(TDA) is essentially a comb filter,it cannot extract the specified harmonics which may be caused by some faults,such as gear ***,TDA always suffers from period cutting error(PCE) to different *** improved TDA methods have been proposed,however they cannot completely eliminate the waveform reconstruction error caused by *** order to overcome the shortcomings of conventional methods,a flexible time domain averaging(FTDA) technique is established,which adapts to the analyzed signal through adjusting each harmonic of the comb *** this technique,the explicit form of FTDA is first constructed by frequency domain ***,chirp Z-transform(CZT) is employed in the algorithm of FTDA,which can improve the calculating efficiency *** the signal is reconstructed in the continuous time domain,there is no PCE in the *** validate the effectiveness of FTDA in the signal de-noising,interpolation and harmonic reconstruction,a simulated multi-components periodic signal that corrupted by noise is processed by *** simulation results show that the FTDA is capable of recovering the periodic components from the background noise ***,it can improve the signal-to-noise ratio by 7.9 dB compared with conventional *** are also carried out on gearbox test rigs with chipped tooth and eccentricity gear,*** is shown that the FTDA can identify the direction and severity of the eccentricity gear,and further enhances the amplitudes of impulses by 35%.The proposed technique not only solves the problem of PCE,but also provides a useful tool for the fault symptom extraction of rotating machinery.

关键词： time domain averaging chirp Z-transform period cutting error de-noising interpolation

Skin-interfaced colorimetric microfluidic devices for ondemand sweat analysis

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npj Flexible Electronics 2023年第1期7卷 100-108页

作者： Weiyi Liu Huanyu Cheng xiufeng wang School of Materials Science and Engineering Xiangtan UniversityXiangtanHunan 411105China Department of Engineering Science and Mechanics The Pennsylvania State UniversityUniversity ParkPA 16802USA

As sweat biomarker levels are continuously changing over metabolism and daily activities,pathological and physiological processes can be dynamically analyzed by wearable *** colorimetric skin-interfaced microfluidic devices that do not have external circuit modules exhibit enhanced deformability with a small ***,it is difficult to achieve sampling over time and self-feedback for closed-loop *** review summarizes recent advances in microfluidic valves for biofluid management and chrono-sampling,as well as active triggers in microfluidics *** enumerating the current limitations in temporal resolution and reliability,we further point out a few potential feasible strategies for future developments.

关键词： interface Skin fluid

H_(2)O_(2) actuated molybdenum oxide nanodots:Multi-enzyme-like activities,leverage of Fenton reaction,and dual-mode sensitive detection of alendronate sodium

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Nano Research 2023年第10期16卷 12106-12115页

作者： Siqi wang Yao Jin Wenhui Ai xiufeng wang Zhiqing Zhang Ting Zhou Guodong Zhang Fang wang Department of Chemistry College of Chemistry and Chemical EngineeringChina University of Petroleum(East China)Qingdao 266580China

Unexpected benefits to the catalytic performance of materials often originate from the presence of surface ***,novel Dpenicillamine modified molybdenum oxide nanodots,with abundant oxygen vacancy defects,were fabrication by a mild,simple,and cost-effective ***–visible(UV–Vis)absorption spectra analysis showed that the nanodots had peroxidaselike and catalase-like *** reactive oxygen species were probed by electronic paramagnetic resonance technique and spectroscopic methods,demonstrating that the nanodots also had oxidase-like ***,the peroxidase-like activity of nanodots was synergistically enhanced in the presence of ferrous ions or ferric ***,less than nanomolar levels of ferrous ions were required to display this phenomenon,meaning Fenton reagent acted as *** on this,a sensitive colorimetric and fluorescent dual-mode sensor for alendronate sodium was *** linear ranges for colorimetric and fluorescence analysis were 0.2–2.5 and 0.2–2.0μM,with detection limits of 31.21 and 71.84 nM,*** method has a simple large-scale material preparation process with higher sensitivity and shorter reaction time,which can inspire and enlighten the design of nanozyme sensors.

关键词： nanozyme molybdenum oxide Fenton reaction alendronate sodium multi-enzyme-like activities

Effective modification of MgO with surface transition metal oxides for NF_3 decomposition

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Journal of Natural Gas Chemistry 2011年第5期20卷 457-459页

作者： Yanan wang xiufeng Xu PeiSheng Hongguang Li Tingting wang Youfen Huang Fangshu Liu School of Chemistry and Chemical Engineering Yantai University Yantai 264005 Shandong China

NF3 decomposition over transition metal oxides coated MgO reagents in the absence of water is investigated. The results show that NF3 can be decomposed completely over pure MgO but the time of NF3 steady full conversion kept as short as 80 min, while the reactivities of coated MgO reagents were remarkably enhanced by transition metal oxides, for example the time of NF3 complete conversion over 12%Fe/MgO extended to 380 min. It is suggested that not only an increase in surface area but also a significant enhancement in the fluorination of MgO substrate caused by the surface transition metal oxides result in an improved reactivity of coated MgO reagents for NF3 decomposition.

关键词： NF3 decomposition defluorinated reagents transition metal oxides coated MgO reactivity

Preparation of SiO_2 microspheres with sodium ions and self-assembly of photonic crystals

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Chinese Science Bulletin 2010年第8期55卷 766-770页

作者： LIU LiYing wang xiufeng ZHANG ChunXiang CHENG Bing School of Materials Science and Engineering Shaanxi University of Science and Technology Xi' an 710021 China

SiO2 microspheres were prepared via a novel co-precipitation *** Na + ions were introduced by adding sodium chloride and metal sodium in solution systems for improving surface charge of the SiO2 *** then SiO2 photonic crystals were fabricated by the vertical deposition *** electrical properties,micromorphology and optical properties were characterized by zeta potential instrument,scanning electron microscope (SEM) with energy dispersive X-ray spectroscopy and Uv-Vis-Nir *** potential of the SiO2 microspheres modified by sodium chloride and metal sodium were averagely heightened 11.39 mV and 13.52 mV respectively in ethanol *** spectra showed that there was Na element in the SiO2 *** images showed that the average size of the SiO2 microspheres modified by sodium chloride and metal sodium were 380 nm and 354 nm respectively,larger than that of the unmodified ones,and their distribution standard deviation was less than 5%,and the sample of SiO2 photonic crystals was face-centered cubic structure with their (111) planes parallel to the *** addition,absorption spectra showed that photonic band gap of the SiO2 photonic crystals was modified by sodium chloride and metal sodium located in 856 nm and 798 nm ***,their absorption peaks became narrower and higher and exhibited a red-shift phenomenon.

关键词：二氧化硅微球光子晶体钠离子自我组装制备扫描电子显微镜红外分光光度计 X射线光谱

Two-stage seedling cultivation method for sweet peppers combining closed plant factory and solar greenhouse

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International Journal of Agricultural and Biological Engineering 2023年第6期16卷 56-66页

作者： Hongbo Cui Fang Ji Yanni Liu Zhengyang Luo xiufeng wang Jianfeng wang Key Laboratory of Facility Vegetable of Jilin Province Jilin Academy of Vegetable and Flower SciencesChangchun 130119China Key Laboratory of Agricultural Engineering in Structure and Environment of MARA College of Water Resources&Civil EngineeringChina Agricultural UniversityBeijing 100083China College of Horticulture Jilin Agricultural UniversityChangchun 130033China

This study introduced a two-stage cultivation method for sweet pepper seedlings, integrating the strengths of a closed plant factory and solar greenhouse, to mitigate the environmental constraints in Northeast China during the early spring season. In the first stage, seedlings were cultivated in a closed plant factory, followed by a second stage in a solar greenhouse. Four treatments- T1 (9 and 36 d), T2 (12 and 33 d), T3 (15 and 30 d), and T4 (18 and 27 d) - were designed for the first and second stages, respectively, with solar greenhouse-only approach serving as the control (CK). The findings reveal that the two-stage methodology significantly outperformed the control across multiple metrics, including seedling health index, chlorophyll content, photosynthetic capacity, yield, etc. Specifically, T3 emerged as optimal, boosting the health index by 38.59%, elevating chlorophyll content by 39.61%, increasing net photosynthesis by 34.61%, and augmenting yield per plant by 40.67%. Additionally, T3 expedited the time to harvest by 25 d compared to the control. Although the seedling cost for T3 was 0.12 RMB yuan higher, the benefits offset the additional investment. In conclusion, the two-stage cultivation method effectively leverages the advantages of both closed-plant factories and solar greenhouses, resulting in superior seedling quality compared to using only solar greenhouses. It offers a practical and economically viable solution for enhancing the quality and yield of sweet pepper seedlings, thus contributing to the progress in the field of facility seedling cultivation research.

关键词： two-stage seedling cultivation sweet peppers closed plant factory solar greenhouse

Analyzing CO_(2) concentration changes and their influencing factors in Indonesia by OCO-2 and other multi-sensor remote-sensing data

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International Journal of Digital Earth 2018年第8期11卷 825-844页

作者： Shuai Yin xiufeng wang Heri Santoso Hiroshi Tani Guosheng Zhong Zhongyi Sun Graduate School of Agriculture Hokkaido UniversitySapporoJapan Research Faculty of Agriculture Hokkaido UniversitySapporoJapan c Indonesian Oil Palm Research Institute MedanNorth SumatraIndonesia

We used OCO-2 products and considered three factors that potentially affect CO_(2) concentration in Indonesia:sea surface temperature(SST),forest fires and *** 2014 to 2016,CO_(2) concentration in Indonesia showed a trend of increase,which is consistent with the global increase reported by the Greenhouse Gases Observing Satellite(GOSAT)*** an archipelago country,the results indicate that SST has a direct effect on the CO_(2) concentration in *** changing exhibits similar fluctuations;meanwhile,CO_(2) concentration and SST also presented positive *** 2015,the number of fire hotspots suddenly increased to 140,699,because of occurrence of the worst forest *** to special geographic conditions,forest fires did not induce CO_(2) concentration changes in Indonesia,but CO_(2) concentration in the corresponding islands showed a trend of ***_(2) concentration increased in Kalimantan during the occurrence of forest fire in September–October 2014,and CO_(2) concentration increased in Kalimantan and Sumatra during the occurrence of forest fire in September–October *** indices were stable and presented no correlation with CO_(2) *** study demonstrated that OCO-2 is capable of monitoring CO_(2) concentration at a regional scale;additionally,an effective method for using OCO-2 Level 2 products is proposed.

关键词： GOSAT Kalimantan SST Sumatra X_(CO_(2))