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Recent progress in thermodynamics of radiation——exergy of radiation, effective temperature of photon and entropy constant of photon

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Science China(Technological Sciences) 2008年第8期51卷 1096-1109页

作者： CHEN ZeShao MO SongPing hu peng Department of Thermal Science&Energy Engineering University of Science and Technology of ChinaHefei 230027China

The recent progress on thermodynamic properties of spectral radiant energy in the field of thermodynamics of radiation is reviewed. The effective temperature of photon Tλ representing the energy quality of photon is introduced. The relation between Tλ and the wavelength λ is given as λTλ =c3=5.33016×10?3 m·K. The en- tropy constant of photon is given as sλ=3.72680×10?23 J/K. The exergy, entropy and enthalpy of the spectral blackbody radiation, the equilibrium cavity radiation, the radiation flux in open system are discussed by using Tλ and sλ, as well as the en- tropy change in the process of the state transformation of photon gas. By analyzing the exergy of spectral radiation, the exergy efficiency of spectral radiant energy available for photosynthesis is proved to be higher than that of light energy. The method for the irreversible loss of exergy calculation in radiant energy converters is also discussed.

关键词： thermodynamics of radiation photon gas exergy photon entropy non-equilibrium thermodynamics

Void defect detection in ball grid array X-ray images using a new blob filter

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Journal of Zhejiang University-Science C(Computers and Electronics) 2012年第11期13卷 840-849页

作者： Shao-hu peng Hyun Do NAM Department of Electronics and Electrical Engineering Dankook University

Ball grid arrays (BGAs) have been used in the production of electronic devices/assemblies because of their advantages of small size, high I/O port density, etc. However, BGA voids can degrade the performance of the board and cause failure. In this paper, a novel blob filter is proposed to automatically detect BGA voids presented in X-ray images. The proposed blob filter uses the local image gradient magnitude and thus is not influenced by image brightness, void position, or component interference. Different sized average box filters are employed to analyze the image in multi-scale, and as a result, the proposed blob filter is robust to void size. Experimental results show that the proposed method obtains void detection accuracy of up to 93.47% while maintaining a low false ratio. It outperforms another recent algorithm based on edge detection by 40.69% with respect to the average detection accuracy, and by 16.91% with respect to the average false ratio.

关键词： Ball grid array (BGA) X-ray Defect detection Blob detection Void detection

Fabrication of Optical Tunable Helical Thin Films

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Journal of Materials Science & Technology 2012年第2期28卷 97-102页

作者： Linxin hu peng Wang Xingyang Wan Shaoji Jiang State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen University Guangzhou 510275 China

Circular polarization selection of light is an important property of helical *** helical thin films fabricated by glancing angle deposition can provide both circular polarization selection and wavelength tuning in this *** selective transmissions were depicted in calculations and *** wavelength tuning mechanism was revealed as the relationship between peak wavelength and deposition ***,tunable circular polarization components can be designed according to the mechanism mentioned above and fabricated by glancing angle deposition *** applications include tunable optical filters,optical pulse-shapers,biosensors etc.

关键词： Glancing angle deposition Helical thin films Circular polarization selectivetransmission Wavelength tuning

Constacyclic Codes of Length Ps over Finite Rings FPm+uFPm+vFPm+uvFPm

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Wuhan University Journal of Natural Sciences 2020年第4期25卷 311-322页

作者： hu peng LIU Xiusheng School of Mathematics and Physics Hubei Polytechnic UniversityHuangshi 435003HubeiChina

Let R-Fpm+uFpm+vFpm+uvFpm,where u2=v2=0,uv=*** R is a local ring,but it is not a chain ring.R contains precisely(pm-1)p3 m units,namely,α+uβ+vγ+uvδ,where α,β,γ,δ∈Fpm,α≠*** this paper,we investigate all constacyclic codes of length ps over ***,we classify allα-constacyclic and(α+uvβ)-constacyclic codes of length ps over R,respectively,and obtain their structure in each of thoseα-constacyclic and(α+uvβ)-constacyclic ***,we address the(α+uβ)-constacyclic codes of length ps over R,and get their classification and ***,using similar discussion of(α+uβ)-constacyclic codes,we obtain the classification and the structure of α+vβ,α+uβ+uvγ,α+vβ+uvγ,α+uβ+vγ,α+uβ+vβ+uvδ-constacyclic codes of length ps over R.

关键词： constacyclic codes local rings ideals

Upgrade Combination Response Is Limited by Prolonged Nucelos(t)ide Analogue Therapy in HBeAg-positive Chronic Hepatitis B:A Real-life Study

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Journal of Clinical and Translational Hepatology 2018年第1期6卷 11-17页

作者： Qiaohe Wang hu Li Daohai Ding Mingli peng Hong Ren peng hu Department of Infectious Diseases Institute for Viral HepatitisThe Key Laboratory of Molecular Biology for Infectious DiseaseChinese Ministry of EducationThe Second Affiliated Hospital of Chongqing Medical UniversityChongqingChina Department of Infectious Diseases Institute for Viral HepatitisThe Key Laboratory of Molecular Biology for Infectious DiseaseChinese Ministry of EducationThe Second Affiliated Hospital of Chongqing Medical UniversityChongqing 400010China

Background and Aims:Few previous studies have reported on a combination response(hepatitis B virus(HBV)DNA undetected,alanine aminotransferase normalization and hepatitis B e antigen(HBeAg)seroconversion)following nucleos(t)ide analogue(NAs)long-term therapy in patients with chronic hepatitis B(CHB).This study aimed to investigate the combination response on long-term NAs therapy in patients with HBeAg-positive CHB and to determine whether prolonged therapy is beneficial for combination response,particularly in optimal patients(baseline alanine aminotransferase level≥5 upper limit of normal and HBV DNA level<10^(9) copies/mL).Methods:In total,280 HBeAg-positive CHB patients were enrolled in this *** them,190 were treated with entecavir and 90 were treated with ***:The cumulative rates of combination response in the total number of patients were 8.6%at 1 year,13.2%at 2 years,19.1%at 3 years,24.2%at 4 years and 26.0%at 5 *** optimal patients,the cumulative rate of combination response was significantly higher than that in the non-optimal patients at 3 years(p=0.043);the trend of the cumulative rate was not strong at the later ***,in optimal patients,combination response mainly occurred in the first 3 *** analysis identified HBeAg/anti-HBe seroconversion at 1 year as the only factor for combination response in optimal patients(hazard ratio:16.321;p=0.000).During the 3 years,the proportion with aspartate aminotransaminase to platelet ratio index≤0.5 increased from 15.6%at baseline to 71.3%at year ***:Upgrading the rate of combination response is limited by prolonging the treatment duration of NAs from 3 years to 5 years in HBeAg-positive CHB patients;a new switch treatment strategy modification should be considered,particularly in optimal patients.

关键词： Chronic hepatitis B Combination response Nucleos(t)ide analogue Long-term therapy

International normalized ratio and Model for End-stage Liver Disease score predict short-term outcome in cirrhotic patients after the resolution of hepatic encephalopathy

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World Journal of Gastroenterology 2019年第26期25卷 3426-3437页

作者： Xiao-peng hu Jian Gao Second Clinical College Chongqing Medical UniversityChongqing 400010China Department of Gastroenterology Second Affiliated HospitalChongqing Medical UniversityChongqing 400010China

BACKGROUND In patients with cirrhosis,hepatic encephalopathy(HE)indicates a poor prognosis despite the use of artificial liver and liver transplantation,presenting as frequent hospitalizations and increased mortality *** To determine predictors of early readmission and mid-term mortality in cirrhotic patients discharged after the resolution of *** From January to February 2018,213 patients were enrolled in this observational study assessing all the successive patients with cirrhosis discharged from Department of Gastroenterology and Department of Infectious and Liver Diseases,Second Affiliated Hospital of Chongqing Medical University after the resolution of *** patients were followed for 6 *** each subject,demographic,clinical,and laboratory variables were assessed at the time of diagnosis of HE,during hospital stay,at discharge,and during *** primary endpoints were incidence of early readmission and mid-term *** During follow-up,65(31%)patients experienced an early *** normalized ratio(INR)[odds ratio(OR)=2.40;P=0.003)at discharge independently predicted early *** incidence of early readmission was significantly higher in patients with an INR>1.62 at discharge than in those with an INR≤1.62(44%vs 19%;P<0.001).Model for End-stage Liver Disease(MELD)score(OR=1.11;P=0.048)at discharge proved to be an independent predictor of early readmission caused by ***(OR=0.97;P=0.005)at discharge proved to be an independent predictor of non-early *** 6 months of follow-up,34(16%)patients *** liver use(hazard ratio=6.67;P=0.021)during the first hospitalization independently predicted mid-term *** INR could be applied to identify fragile cirrhotic patients,MELD score could be used to predict early relapse of HE,and anemia is a potential target for preventing early readmission.

关键词： Cirrhosis Hepatic encephalopathy Patient readmission Mortality Observational study Risk factor

Magnet stage optimization of 5 kW multi-cusped field thruster

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Plasma Science and Technology 2020年第9期22卷 128-138页

作者： peng hu Daren YU Yan SHEN Beijing Institute of Control Engineering Beijing 100094People's Republic of China Lab of Advanced Space Propulsion Beijing 100094People’s Republic of China Beijing Engineering Research Center of Efficient and Green Aerospace Propulsion Technology Beijing 100094People’s Republic of China Plasma Propulsion Laboratory of Harbin Institute of Technology Harbin 150001People's Republic of China School of Aeronautics and Astronautics Sun Yat-sen UniversityGuangzhou 510006People's Republic of China

The multi-cusped field thruster is a unique electric thruster device,which has many advantages such as long lifetime,large-range thrust throttling ability,high thrust density,and low *** thruster employs several alternating polarity permanent magnets to create a periodic magnetic field with several *** studies have indicated that the basic ionization and acceleration processes are directly related to the electron motion behavior,which mainly depends on the magnetic field *** magnet number and magnet stage length are two key magnetic field parameters that have important effects on the thruster *** this paper,both the magnet number and magnet stage length parameters are studied for the optimization of a 5 k W multi-cusped field *** results indicate that the three-stage thruster has a better electron confinement than the two-stage *** has lower ion energy loss at the wall,and shows a higher ionization ***,the three-stage magnetic field is a superior magnetic field ***,the three-stage magnetic field simulation results indicate that an optimal accelerating electric field distribution and ionization region distribution could be obtained when the magnet length ratio is 78:25:20.

关键词： multi-cusped field magnet number magnet length performance optimization

Numerical investigation of thermocapillary migration of the drop for large Marangoni numbers

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Science China(Technological Sciences) 2007年第5期50卷 694-696页

作者： GAO peng YIN Zhaohua hu WenRui National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China National Microgravity Laboratory Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

An axisymmetric model is adopted to simulate the problem of unsteady drop thermocapillary motion for large Marangoni numbers. Front tracking methods are used in the investigation. It is found that the non-dimensional drop migration ve- locity will decrease with increasing Marangoni number. This agrees well with the experimental results obtained from the 4th Shen-Zhou space ship. In the meanwhile, this is also the first time for numerical simulations to verify the experimental phe- nomenon under large Marangoni numbers.

关键词： thermocapillary migration of drops, microgravity, front tracking methods

On the gauge dependence of scalar induced secondary gravitational waves during radiation and matter domination eras

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Science China(Physics,Mechanics & Astronomy) 2023年第9期66卷 23-41页

作者： Arshad Ali Ya-peng hu Mudassar Sabir Taotao Sui College of Physics Nanjing University of Aeronautics and AstronauticsNanjing 211106China Key Laboratory of Aerospace Information Materials and Physics(NUAA) MIITNanjing 211106China Center for Gravitation and Cosmology College of Physical Science and TechnologyYangzhou UniversityYangzhou 225009China School of Geophysics and Geomatics China University of GeosciencesWuhan 430074China

We revisit the vital issue of gauge dependence in the scalar-induced secondary gravitational waves(SIGWs), focusing on the radiation domination(RD) and matter domination(MD) eras. The energy density spectrum is the main physical observable in such induced gravitational waves. For various gauge choices, there has been a divergence in the energy density, ?GW, of *** calculate SIGWs in diferent gauges to quantify this divergence to address the gauge-dependent problem. In our previous studies, we had found that the energy density diverges in the polynomial power of conformal time(e.g., η^(6) in uniform density gauge). We try to fix this discrepancy by adding a counter-term that removes the fictitious terms in secondary tensor perturbations. We graphically compare the calculations in various gauges and also comment on the physical origin of the observed gauge dependence.

关键词： scalar induced gravitational waves gauge transformation cosmology

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