The Nuclear Techniques and the Selection of Model Parameters in Big Data

Wang Chunhong 보안공학연구지원센터 2014 International Journal of Database Theory and Appli Vol.7 No.6

Now a large scale of data every day, the large-scale data is usually in the form of database storage. The law of the people wants to find useful or knowledge, thus was born the Data Mining technology. SVM (Support Vector Machine, SVM) is a very useful method in data mining, this paper mainly discusses the Support Vector Machine (SVM) play a key role in nuclear techniques and the selection of model parameters is analyzed and evaluated. This article some methods about how to construct the kernel function is introduced for the model to find suitable kernel function is to provide some reference strategies and proposed kernel function method for the simulation analysis.

Integral Sliding Mode Control Based on Command Filtering Backstepping for Dual-motor Servo Systems with Torque Disturbance

Chunhong Jin,Baofang Wang,Mingjie Cai 제어·로봇·시스템학회 2023 International Journal of Control, Automation, and Vol.21 No.6

In order to mitigate the influence of the torque disturbance and improve the tracking performance of the dual-motor servo system, this paper designs a controller by combining adaptive command filtering backstepping (CFB) and integral sliding mode control (ISMC). First of all, CFB is utilized to overcome the “explosion of complexity” problem from the traditional backstepping method. And the error compensation mechanism is designed for reducing the filtering errors. Meanwhile, the integral items are designed in the sliding mode surfaces which are novel functions of compensated tracking errors for suppressing the steady-state error, improving the tracking precision. The signum functions are replaced by the saturation functions in switching control laws, which reduces the chattering phenomenon. In addition, synchronization feedback signals are designed in the virtual control laws to ensure the synchronization performance between two motors. The total actual control law is derived, and the system stability as well as state convergence is proved by employing Lyapunov theory. In the end, the simulation research is carried out and the results show the advantage of the proposed control strategy. In order to mitigate the influence of the torque disturbance and improve the tracking performance of the dual-motor servo system, this paper designs a controller by combining adaptive command filtering backstepping (CFB) and integral sliding mode control (ISMC). First of all, CFB is utilized to overcome the “explosion of complexity” problem from the traditional backstepping method. And the error compensation mechanism is designedfor reducing the filtering errors. Meanwhile, the integral items are designed in the sliding mode surfaces which are novel functions of compensated tracking errors for suppressing the steady-state error, improving the trackingprecision. The signum functions are replaced by the saturation functions in switching control laws, which reduces the chattering phenomenon. In addition, synchronization feedback signals are designed in the virtual control lawsto ensure the synchronization performance between two motors. The total actual control law is derived, and the system stability as well as state convergence is proved by employing Lyapunov theory. In the end, the simulationresearch is carried out and the results show the advantage of the proposed control strategy.

The effect of aeration mode on the operational effectiveness and membrane bioreactors for greywater treatment and membrane fouling

Chunhong Shi,Bo Yan,Xiangmeng Zuo,Cheng Wang,Zifu Li,Lixin Zhu 대한환경공학회 2023 Environmental Engineering Research Vol.28 No.2

This study aims to investigated the effect of aeration mode on membrane bioreactors (MBRs) using a self-designed integrated hollow fiber MBR and flat sheet organic MBR for rural greywater treatment. The pollutant removal efficiency, characteristics of activated sludge and mixed liquor, and mechanisms of membrane fouling were systematically analyzed under intermittent aeration and continuous modes. The results indicate that the permeability of MBRs in intermittent aeration mode is higher than that in the continuous aeration mode when operating at the same aeration rate. Due to the higher extracellular polymeric substance (EPS) and soluble microbial product (SMP) concentrations. The removal rates of TN and TP by both MBRs at the intermittent aeration mode were higher than those in the continuous aeration mode due to the difference in the aeration environment. Compared to the flat-sheet organic membrane, the hollow-fiber membrane surface was more likely to form biofilms, which cause biological fouling.The relative abundance of Thermomonas showed a positive correlation with the EPS concentration, indicating that Thermomonas participates in EPS synthesis. This study provides a theoretical basis for evaluating the influence of aeration modes on MBRs,and would be a useful guide for the better control of membrane fouling and treatment of rural greywater.

Design of Novel Reactive Dyes Containing Cationic Groups: Mechanism and Application for Environmentally Friendly Cotton Dyeing

Meihui Wang,Chong Guo,Chunhong Li,Tao Zhao 한국섬유공학회 2020 Fibers and polymers Vol.21 No.12

In this work, four novel, high fixation reactive dyes containing cationic groups were synthesized using maminophenyltrimethylammoniumsalt or 4-(ethylsulfurate sulfonyl) aniline as the diazo component, 3-(N,N-diethylamino)acetanilide or 3’-aminoacetanilide as the coupling component and m-aminophenyltrimethylammonium salt or N-(2-aminoethyl)pyridinium chloride as the cationic group. The synthesized dyes containing multiple cationic groups were characterized by FTIRand 1H-NMR spectroscopy. The spectral properties were measured by UV-Vis absorption spectroscopy. Compared withconventional reactive dyes containing cationic groups, the synthesized dyes exhibited good water solubility uponintroduction of a quaternary ammonium into the chromophore. The structural design of synthetic azo dyes allows enhancedthe water solubility due to the introduction of a cationic group. The dyeing properties of the synthesized dyes to cotton fabricwere explored at various temperatures and salt and alkaline concentrations. The results showed that the synthesized dyespossessed good dyeing properties with nearly 80% fixation and good color fastness on cotton (3-5) in the absence of salt. Thesuccess of the salt-free dyeing of cotton fabric with these dyes is an excellent example of environmentally friendly cottondyeing. This study provides an important platform for the design of novel reactive dyes for cotton dyeing to reduce effluentpollution.

An improved unified description of charge-carrier mobilities in disordered organic semiconductors

Liguo Wang,Huaiwu Zhang,Xiaoli Tang,Chunhong Mu,Jun Li 한국물리학회 2010 Current Applied Physics Vol.10 No.4

An improved unified description of the dependence of the charge-carrier mobility on temperature, carrier density, and electric field in disordered organic semiconductors is proposed based on the Arrhenius temperature dependence ln(μ) ∝ / 1=T and non-Arrhenius temperature dependence ln(μ) ∝ / 1=T2. The improved description of the mobility can quite well fit the numerical solution of the master equation at both the low densities and high densities, the latter of which cannot be accurately described using the model introduced by Pasveer et al. [6]. Experimental current–voltage characteristics in devices based on organic semiconductors are also excellently reproduced with this improved description. Finally, we calculate and analyze the distribution of the charge-carrier density and electric field with position in polymer layer for two organic semiconductors in detail by using the improved description.

Synergistic effect of novel ionic liquid/graphene complex on the flame retardancy of epoxy nanocomposites

Zhang Chunhong,Xu Zice,Sui Wenbo,Zang Junbo,Ao Yuhui,Wang Lu,Shang Lei 한국탄소학회 2023 Carbon Letters Vol.33 No.2

Epoxy resin (EP) is a thermosetting resin with excellent properties, but its application is limited due to its high brittleness and poor flame retardancy. Therefore, to solve this problem, a dispersion system of imidazole-containing ionic liquid ([Dmim]Es) and graphene in epoxy resin is designed based on the π–π stacking effect between imidazole and graphite layers. The study on the thermal and flame-retardant properties of the composites show that the modified [Dmim]Es–graphene nanosheets improved the flame retardancy, smoke suppression and thermal stability of epoxy resin. With the addition of 5wt% [Dmim]Es and 1% Gra, the exothermic rate (HRR) and total exothermic (THR) of the composites decrease by 35% and 30.2% compared with the untreated epoxy cross-linking, respectively. The limiting oxygen index reaches 33.4%, the UL-94 test rating reaches V-0. The characterization of mechanical properties shows that the tensile properties and impact properties increased by 13% and 30%, respectively. Through SEM observation, the addition of [Dmim]Es improves the dispersion of graphene in the EP collective and changes the mechanical fracture behavior. The results show that ionic liquid [Dmim]Es-modified graphene nanosheets are well dispersed in the matrix, which not only improves the mechanical properties of epoxy resin (EP), but also has a synergistic effect on flame retardancy. This work provides novel flame-retardant and graphene dispersion methods that broaden the range of applications of epoxy resins.

Influence of Hemp Fiber Softening Treatment & Blend Ratio on Quality Characteristics of Hemp-Based Ternary Blended YARNS

Chuanhe Li,Ruiqi Shao,Chunhong Wang,Guangwei Fu,Bingjie Yang 한국섬유공학회 2023 Fibers and polymers Vol.24 No.10

Quality characteristics of blended yarns, which play an important role in textile quality, are continually assessed by softness, breaking strength, breaking elongation, hairiness, irregularity, etc. In this study, hemp was softened and blended with other cellulose fibers with better softness to produce yarns. The softness of hemp is obviously lower than that of the other two fibers. With the increase of hemp fiber percentage content, the yarn properties deteriorated. Therefore, the softening treatment of hemp fiber is very necessary. Moreover, the blending hemp, cotton, and viscose in the yarn structure provided synergies, improving the weak properties of ternary fibers. Results show that softening treatment and lower percentage content of the hemp fiber will result in better yarn quality, which is consistent with the derivation result of the bending theoretical model. When the percentage content of treated hemp is 40 wt%, the overall performance of blended yarn is the best. Compared with the untreated hemp-based ternary blended yarns, the hairiness of blended yarn is significantly less (3.65 ends/m, compared to 12.23 ends/m), and the irregularity of yarn is lower (27.33% and 27.70%, respectively), yarn quality improved considerably. In addition, the resulting hemp yarn showed antibacterial activity against Escherichia coli and Staphylococcus aureus.

Lactobacillus rhamnosus Granules Dose-Dependently Balance Intestinal Microbiome Disorders and Ameliorate Chronic Alcohol-Induced Liver Injury

Zelin Gu,Yanfeng Wu,Yu Wang,Haiyue Sun,Ying You,Chunhong Piao,Junmei Liu,Yuhua Wang 한국식품영양과학회 2020 Journal of medicinal food Vol.23 No.2

As the functions of Lactobacilli become better understood, there are increasing numbers of applications for Lactobacillus products. Previously, we have demonstrated that Lactobacillus rhamnosus GG (LGG) can prevent alcoholic liver injury. LGG granules were produced by fluid bed granulation with a media composed of starch, skimmed milk powder, whey powder, microcrystalline cellulose and maltose, and LGG fermented liquid that comprised 30–50% of the total weight. We found LGG granules dose-dependently protected against chronic alcoholic liver disease. When alcohol was consumed for 8 weeks with LGG treatment during the last 2 weeks, we demonstrated that the dose dependence of LGG granules can improve alcohol-induced liver injury through decreasing the levels of lipopolysaccharide and tumor necrosis factor-α in serum and prevent liver steatosis by suppressing triglyceride, free fatty acid, and malondialdehyde production in liver. Alcohol feeding caused a decline in the number of both Lactobacillus and Bifidobacterium, with a proportional increase in the number of Clostridium perfringens in ileum, and expansion of the Gram-negative bacteria Proteobacteria, Campylobacterales, and Helicobacter in cecum. However, LGG granule treatment restored the content of these microorganisms. In conclusion, LGG granule supplementation can improve the intestinal microbiota, reduce the number of gram-negative bacteria, and ameliorate alcoholic liver injury.

Photocatalytic Degradation Mechanism of Tetracycline by Ag@ZnO/C Core–Shell Plasmonic Photocatalyst Under Visible Light

Longbao Yu,Zhefei Ye,Jinze Li,Chunhong Ma,CHANGCHANG MA,XINLIN LIU,Huiqin Wang,Lili Tang,Pengwei Huo,Yongsheng Yan 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.6

A series of hamburger-like Ag@ZnO/C core–shell plasmonic photocatalysts have been synthesized via a simple solvothermal method for degradation of tetracycline (TC) under visible light irradiation, possessing high photocatalytic activity and good stability. The presence of localized surface plasmon resonance (LSPR) in the Ag core has increased the photocatalytic activity over an extended wavelength range. The plasmon-induced resonant energy transfer (PIRET) and direct electron transfer (DET) have facilitated the excitation and separation of photogenerated e-/h+pairs, which has been further confirmed by electrochemical investigations. The presences of hydroxyl radicals ( ·OH), superoxide radicals ( · O-2) and singlet oxygen (1O2) in the photocatalytic reaction system of Ag@ZnO/C photocatalyst have been demonstrated by electron spin resonance (ESR) measurements. All of the experiment results indicate that the ternary structure of Ag@ZnO/C can effectively enhance the photocatalytic activity. Furthermore, the effects of introduced Ag contents and carbon source dosage were researched by comparative photocatalytic experiments, and the potential structures of photodegradation products were studied by HPLC-MS.

Effect on Viability of Microencapsulated Lactobacillus rhamnosus with the Whey Proteinpullulan Gels in Simulated Gastrointestinal Conditions and Properties of Gels

Minghao Zhang,Dan Cai,Qiumei Song,Yu Wang,Haiyue Sun,Chunhong Piao,Hansong Yu,Junmei Liu,Jingsheng Liu,Yuhua Wang 한국축산식품학회 2019 한국축산식품학회지 Vol.39 No.3

Lactobacillus rhamnosus GG (LGG) has low resistance to low pH and bile salt in the gastrointestinal juice. In this study, the gel made from whey protein concentrate (WPC) and pullulan (PUL) was used as the wall material to prepare the microencapsulation for LGG protection. The gelation process was optimized and the properties of gel were also determined. The results showed the optimal gel was made from 10% WPC and 8.0% PUL at pH 7.5, which could get the best protective effect; the viable counts of LGG were 6.61 Log CFU/g after exposure to simulated gastric juice (SGJ) and 9.40 Log CFU/g to simulated intestinal juice (SIJ) for 4 h. Sodium dodecyl sulphite polyacrylamide gel electrophoresis (SDS-PAGE) confirmed that the WPC-PUL gel had low solubility in SGJ, but dissolved well in SIJ, which suggested that the gel can protect LGG under SGJ condition and release probiotics in the SIJ. Moreover, when the gel has highest hardness and water-holding capacity, the viable counts of LGG were not the best, suggesting the relationship between the protection and the properties of the gel was non-linear.