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Universal Grammar and Second Language Acquisition

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海外英语 2018年第17期 23-24页

作者：陈珊 Changde Vocational Technical College Changde 415000 China

Universal Grammar,whose main focus is on first language acquisition,is a major linguistic theory exerting profound influence on second language acquisition.This paper is a tentative explanation to whether the set of rules of UG can still be accountable for SLA.Moreover,some suggestions are given to the future development toward the relationship of UG and SLA.

关键词：英语学习学习方法阅读知识阅读材料

Research and Analysis of the Error of an Unequal Arm Buoyancy Balance

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International Journal of Plant Engineering and Management 2009年第2期14卷 122-128页

作者： REN Feng-lan ZHU Xi-min Changde Vocational Technical College Changde 415000 China

The basic structure and working principle of an unequal-arm buoyancy balance are introduced in this article. Different kinds of error produeed in the unequal-arm buoyancy balance has been researched and analyzed. First the temperature influence of the crossbeam is analyzed, then the measurement error is calculated; second, the error produced by the pivot and the counterweight system is analyzed, then the corresponding error reduction method is proposed. It is shown that the error reduction method can promote the precision of the buoyancy, which is critical to balance.

关键词： unequal-ann buoyancy balance precision water pump error analysis

Campus Construction Featuring Plant Landscapes: A Case Study of Guang'an vocational & technical college

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Journal of Landscape Research 2019年第2期11卷 4-7页

作者： YAO Dequan Guang'an vocational & technical college

SStarting from the analysis of the significance of characteristic plant landscapes in the campus, this paper took Guang'an vocational & technical college for example, combined with the greening practice of the college, designed the planning layout of "one axis, two phases, three rings, and five areas" of the college, and put forward suggestions for campus construction featuring plant landscapes.

关键词： Plant landscapes Characteristics Campus

Synaptic development of layer V pyramidal neurons in the prenatal human prefrontal neocortex: a Neurolucida-aided Golgi study

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Neural Regeneration Research 2020年第8期15卷 1490-1495页

作者： Li-Xin He Lily Wan Wei Xiang Jian-Ming Li An-Hua Pan Da-Hua Lu Xiangtan Medicine and Health vocational college XiangtanHunan ProvinceChina Department of Neurology Xiangya HospitalCentral South UniversityChangshaHunan ProvinceChina Changde Vocational Technical College ChangdeHunan ProvinceChina Department of Anatomy Changsha Medical UniversityChangshaHunan ProvinceChina Department of Anatomy and Neurobiology Xiangya School of MedicineCentral South UniversityChangshaHunan ProvinceChina

The prefrontal neocortex is involved in many high cognitive functions in humans.Deficits in neuronal and neurocircuitry development in this part of the cerebrum have been associated with various neuropsychiatric disorders in adolescents and adults.There are currently little available data regarding prenatal dendrite and spine formation on projecting neurons in the human prefrontal neocortex.Previous studies have demonstrated that Golgi silver staining can identify neurons in the frontal lobe and visual cortex in human embryos.In the present study,five fetal brains,at 19,20,26,35,and 38 gestational weeks,were obtained via the body donation program at Xiangya School of Medicine,Central South University,China.Golgi-stained pyramidal neurons in layer V of Brodmann area 46 in fetuses were quantitatively analyzed using the Neurolucida morphometry system.Results revealed that somal size,total dendritic length,and branching points of these neurons increased from 26 to 38 gestational weeks.There was also a large increase in dendritic spines from 35 to 38 gestational weeks.These findings indicate that,in the human prefrontal neocortex,dendritic growth in layer V pyramidal neurons occurs rapidly during the third trimester of gestation.The use of human fetal brain tissue was approved by the Animal Ethics Committee of Xiangya School of Medicine,Central South University,China(approval No.2011-045)on April 5,2011.

关键词： Golgi staining human brain banking neurodevelopment Neurolucida neuropsychiatric disorders prefrontal cortex synaptogenesis three-dimensional reconstruction

Environmental Cultural Landscape Characteristics of Agricultural vocational colleges: A Case Study of Bioengineering Branch of Yangling Vocation and technical college and Doucun Farm

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Journal of Landscape Research 2015年第4期7卷 25-28页

作者： CHEN Qi WANG Zhousuo ZHU Zhanbin Yangling vocational & technical college

Based on the overall planning of environmental cultural construction of Yangling vocational & technical college and the college–enterprise co-construction of Doucun Farm, this paper combined environmental cultural reformation inside and outside the college and reform of off-campus teaching experiment farm in view of outstanding agricultural characteristics of the bioengineering branch, with environmental health preservation as the fundamental goal and "health-preserving agriculture" as the link. In addition, four major characteristic landscape frameworks of "point, line, surface, and body" were established, and the effective construction approaches of health-preserving environmental cultural landscapes in vocational colleges were explored.

关键词： Bioengineering Branch Health-preserving agriculture Environmental cultural construction

Propagation characteristics of the silica and silicon subwavelength-diameter hollow wire waveguides

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Chinese Optics Letters 2008年第10期6卷 732-735页

作者：吴熳黄维清王玲玲 School of Physics and Microelectronic Science Hunan UniversityChangsha 410082 Changde Vocational Technical CollegeChangde 415000 School of Physics and Microelectronic Science Hunan UniversityChangsha 410082

The basic propagation properties of the silica and silicon subwavelength-diameter hollow wire waveguides have been investigated by comparison. It shows that the silica and silicon subwavelength-diameter hollow wire waveguides have some interesting properties, such as enhanced evanescent field in the cladding, enhanced intensity in the hollow core, and large waveguide dispersion. For the different confinement ability, the enhanced field in the hollow core and cladding of the silica subwavelength-diameter hollow wire is much stronger than that of the silicon one for the same size.

关键词： Oxides? ?Silica? ?Silicon? ?Waveguides? ?Wire

Tricolor emitting and energy transfer in the phosphor Ba_2ZnSi_2O_7:Ce^(3+),Eu^(3+),Eu^(2+) for white-LED based near-UV chips

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Journal of Rare Earths 2015年第5期33卷 463-468页

作者：邓升智邱忠贤张茂美周文理张吉林李承志荣春英余丽萍廉世勋 Key Laboratory of Chemical Biology & Traditional Chinese Medicine Research (Ministry of Education) Key Laboratory of Sustainable Resources Pro-cessing and Advanced Materials of Hunan Province college college of Chemistry and Chemical Engineering Hunan Normal University Changde Vocational Technical College

The red, green and blue （R/G/B） tricolor emitting phosphors Ba2ZnSi2O7 co-doped with Ce3＋and Eu3＋were synthesized in air atmosphere by a conventional high temperature solid-state reaction technique. All of the excitation spectrum of the phosphor Ba2ZnSi2O7：Ce,Eu showed a strong broad band absorption in the n-UV region whenever monitored by red （630 nm）-emitting or by green （500 nm）-and blue （402 nm）-emitting. Under the excitation of 330 nm, the emission spectrum containing a blue-violet emis-sion band, a green emission and four sharp lines originated from the characteristic transitions of Ce3＋, Eu2＋and Eu3＋ions, of which the relative intensities of the three emission bands could be controlled by the doping concentration of Ce3＋. The ca. CIE chromaticity co-ordinates （x=0.317, y=0.309） of the phosphor Ba1.94ZnSi2O7：0.03Eu,0.01Ce was very close to the standard white （x=0.33, y=0.33）, which suggested that it was a novel single-phased white-light emitting phosphor for LED-based near-UV chip. The mechanisms of energy transfer from Eu2＋to Eu3＋via Ce3＋was also discussed.

关键词： rare earths Ba2ZnSi2O7：Eu,Ce R/G/B tricolor emitting phosphor white-LEDs

Health Status Assessment for New Urban Rail Vehicle Traction Systems Based on Cross Entropy and SVM

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Chinese Journal of Electrical Engineering 2022年第2期8卷 108-120页

作者： Zhenglong Zhou Yang Cheng Shenggang Lv Kai Chen Weijing Du School of Power Technology Liuzhou Railway Vocational Technical CollegeLiuzhou 545616China

A health status assessment method based on cross entropy and support vector machine(SVM)is proposed for the new urban rail vehicle traction systems.First,an index system for health assessment of the traction system is established,and combined weights of the index layer are obtained via cross entropy.Then,an SVM assessment model considering actual operating data and each status level of the traction system is established.Finally,the model is simulated in Matlab to obtain assessment results.The results indicate that the proposed method can provide the health status information of the traction system intuitively and complete the health status assessment of the traction system of the new urban rail vehicle effectively,by exploiting the traction system’s layered analysis model.The health status can be assessed accurately and reliably by adopting the cross entropy theory and SVM theory.

关键词： New urban rail vehicle traction system cross entropy SVM health status assessment

Spin current and its heat effect in a multichannel quantum wire with Rashba spin-orbit coupling

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Chinese Physics B 2011年第7期20卷 387-392页

作者：宋占锋王亚东邵慧彬孙志刚 Zhangjiakou vocational and technical college

Using the perturbation method, we theoretically study the spin current and its heat effect in a multichannel quantum wire with Rashba spin-orbit coupling. The heat generated by the spin current is calculated. With the increase of the width of the quantum wire, the spin current and the heat generated both exhibit period oscillations with equal amplitudes. When the quantum-channel number is doubled, the oscillation periods of the spin current and of the heat generated both decrease by a factor of 2. For the spin current js,xy, the amplitude increases with the decrease of the quantum channel; while the amplitude of the spin current js,yx remains the same. Therefore we conclude that the effect of the quantum-channel number on the spin current js,xy is greater than that on the spin current js,yx. The strength of the Rashba spin-orbit coupling is tunable by the gate voltage, and the gate voltage can be varied experimentally, which implies a new method of detecting the. spin current. In addition, we can control the amplitude and the oscillation period of the spin current by controlling the number of the quantum channels. All these characteristics of the spin current will be very important for detecting and controlling the spin current, and especially for designing new spintronic devices in the future.

关键词： multichannel quantum wire Rashba spin-orbit coupling spin current heat produced by spin current