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相对编码与绝对编码组合的数据采集编码方案 被引量:11
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作者 柏捷 《测绘通报》 CSCD 北大核心 2007年第9期32-34,共3页
提出在数字化测图的数据采集中,宏观采用相对编码微观采用相对编码与绝对编码相配合的方式,实现在全要素编码测图中,仅需输入两三位字符的编码方式,即可实现连线地物的编码连线。本方法不仅编码短,而且编码简单,可极大降低编码输入人员... 提出在数字化测图的数据采集中,宏观采用相对编码微观采用相对编码与绝对编码相配合的方式,实现在全要素编码测图中,仅需输入两三位字符的编码方式,即可实现连线地物的编码连线。本方法不仅编码短,而且编码简单,可极大降低编码输入人员的劳动强度和提高编码的质量。 展开更多
关键词 数据采集 相对编 绝对编 地物属性 连接符 连接
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用AT89C2051设计的PC/AT键盘
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作者 杨日杰 张宗玉 郑立新 《单片机与嵌入式系统应用》 2002年第4期20-21,共2页
在介绍PC/AT键码特征的基础上,介绍利用AT89C2051来实现PC/AT键盘的硬件和软件设计方法。它具有结构简单、选择性强、便于实现等优点,特别适用于36个以下PC/AT键盘的应用。
关键词 AT89C2051 设计 PC/AT键盘 镜码 微控制器
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A Method to Improve Photographing Function of Common Digital Camera to Small Flowers and Fruits 被引量:1
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作者 洪亚平 张亚冰 《Agricultural Science & Technology》 CAS 2009年第6期105-107,共3页
[ Objective] The aim of this study was to solve the problem of photographing small flowers and fruits with a common digital camera in field. [Method] Firstly, the photographic mode of a common digital camera was set ... [ Objective] The aim of this study was to solve the problem of photographing small flowers and fruits with a common digital camera in field. [Method] Firstly, the photographic mode of a common digital camera was set as "macro" (or "soft snap" ) and "flash off". Secondly, the small flower or fruit was magnified with a magnifying glass, and then the magnified flower or fruit was automatically focused with the digital camera lens. After automatic focusing, the shutter button was pressed and the photograph finished. [Result] With this method, the clear inflo- rescence or floral photographs of Eragrostis pilosa ( Gramineae ) , Bidens biternata (Compositae) and Tribulus terrester (Zygophllaceae) were obtained in field. [ Conclusion] The optical system of a digital camera has been changed by the magnifying glass, which improves the photographic function of a common digital camera to small flowers and fruits, and also easily gets their clear photographs. 展开更多
关键词 Digital camera Magnifying glass Photographing FLOWER FRUIT
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A practical application of photogrammetry to performing rib characterization measurements in an underground coal mine using a DSLR camera 被引量:1
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作者 Brent A.Slaker Khaled M.Mohamed 《International Journal of Mining Science and Technology》 SCIE EI CSCD 2017年第1期83-90,共8页
Understanding coal mine rib behavior is important for inferring pillar loading conditions as well as ensuring the safety of miners who are regularly exposed to ribs. Due to the variability in the geometry of undergrou... Understanding coal mine rib behavior is important for inferring pillar loading conditions as well as ensuring the safety of miners who are regularly exposed to ribs. Due to the variability in the geometry of underground openings and ground behavior, point measurements often fail to capture the true movement of mine workings. Photogrammetry is a potentially fast, cheap, and precise supplemental measurement tool in comparison to extensometers, tape measures, or laser range meters, but its application in underground coal has been limited. The practical use of photogrammetry was tested at the Safety Research Coal Mine, National Institute for Occupational Safety and Health(NIOSH). A commercially available, digital single-lens reflex(DSLR) camera was used to perform the photogrammetric surveys for the experiment. Several experiments were performed using different lighting conditions, distances to subject,camera settings, and photograph overlaps, with results summarized as follows: the lighting method was found to be insignificant if the scene was appropriately illuminated. It was found that the distance to the subject has a minimal impact on result accuracy, and that camera settings have a significant impact on the photogrammetric quality of images. An increasing photograph resolution was preferable when measuring plane orientations; otherwise a high point cloud density would likely be excessive. Focal ratio(F-stop) changes affect the depth of field and image quality in situations where multiple angles are necessary to survey cleat orientations. Photograph overlap is very important to proper three-dimensional reconstruction, and at least 60% overlap between photograph pairs is ideal to avoid unnecessary post-processing. The suggestions and guidelines proposed are designed to increase the quality of photogrammetry inputs and outputs as well as minimize processing time, and serve as a starting point for an underground coal photogrammetry study. 展开更多
关键词 PHOTOGRAMMETRY Coal mining UNDERGROUND Rib characterization
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New Mode in Parasites Experimental Teaching --Application and Experience of Interactive Teaching with Digital Microscope System
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作者 Zheng Fengying 《International English Education Research》 2014年第9期73-75,共3页
In order to improve the parasites experimental teaching quality, Digital Microscope System is used to replace the ordinary optical microscope in the teaching of eggs, imagoes, and tissue slices. The new model of exper... In order to improve the parasites experimental teaching quality, Digital Microscope System is used to replace the ordinary optical microscope in the teaching of eggs, imagoes, and tissue slices. The new model of experimental teaching, integrating modem information technology into the parasite experimental teaching, gives full play to the students' learning enthusiasm, initiative and creativity and improves the quality of experimental teaching. And at the same time, it provides a basis for the microbiological and pathological experimental teaching reform. 展开更多
关键词 Digital Microscope interaction experimental teaching EXPERIENCE
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A Monte Carlo Simulation of Radiation Damage of SiC and Nb Using JA-IPU Code 被引量:1
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作者 Nagendra Singh Raghaw Vinod Kumar +2 位作者 Ambika Tundwal Yury Korovin Jindrich Adam 《Journal of Energy and Power Engineering》 2015年第11期967-975,共9页
MC (Monte Carlo) simulation code, JA-IPU is used to study radiation damage of SiC irradiated to spallation neutron and AmBe neutron spectra. The code is based on the major physical processes of radiation damage on i... MC (Monte Carlo) simulation code, JA-IPU is used to study radiation damage of SiC irradiated to spallation neutron and AmBe neutron spectra. The code is based on the major physical processes of radiation damage on incorporation of atomic collision cascade and limited to 10 MeV neutron energy. A phenomenological relation for radiation swelling is also derived. Based on the calculation of swelling, DPA (displacement per atom), defect production efficiency and effective threshold energy, Efff from the data of MC simulation, SiC is inferred to be a highly radiation resistant material when compared with Nb and Ni metals which are used in composition of several reactor steels. Experimental results of hill-hock density measured using AFM (atomic force microscopy), also confirm radiation resistant behavior of SiC. 展开更多
关键词 Monte-Carlo simulation radiation resistant material DPA effective damage threshold energy.
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A mirror-image protein-based information barcoding and storage technology 被引量:1
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作者 Ji-Shen Zheng Jun Liang +4 位作者 Wei-Wei Shi Ying Li Hong-Gang Hu Chang-Lin Tian Lei Liu 《Science Bulletin》 SCIE EI CSCD 2021年第15期1542-1549,M0004,共9页
A mirror-image protein-based information barcoding and storage technology wherein D-amino acids are used to encode information into mirror-image proteins that are chemically synthesized is described.These mirror-image... A mirror-image protein-based information barcoding and storage technology wherein D-amino acids are used to encode information into mirror-image proteins that are chemically synthesized is described.These mirror-image proteins were then fused into various materials from which information-encoded objects were produced.Subsequently,the mirror-image proteins were extracted from the objects using biotin-streptavidin resin-mediated specific enrichment and cleaved using an Ni(Ⅱ)-mediated selective peptide cleavage.Protein sequencing was accomplished using liquid chromatography/tandem mass spectrometry(LC-MS/MS)and then transcoded into the recorded information.We demonstrated the use of this technology to encode Chinese words into mirror-image proteins,which were then fused onto a poly(ethylene terephthalate)(PET)film and retrieved and decoded by LC-MS/MS sequencing.Compared to information barcoding and storage technologies using natural biopolymers,the mirrorimage biopolymers used in our technology may be more stable and durable. 展开更多
关键词 Mirror-image proteins Information barcoding and storage Chemical protein synthesis Protein-of-things Protein sequencing
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The staphylococcal nuclease prevents biofilm formation in Staphylococcus aureus and other biofilm-forming bacteria 被引量:3
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作者 TANG JunNi KANG MingSong +4 位作者 CHEN HuanChun SHI XianMing ZHOU Rui CHEN Juan DU YiWu 《Science China(Life Sciences)》 SCIE CAS 2011年第9期863-869,共7页
The staphylococcal nuclease, encoded by the nucl gene, is an important virulence factor of Staphylococcus aureus. However, the physiological role of the nuclease has not been fully characterized. The current study obs... The staphylococcal nuclease, encoded by the nucl gene, is an important virulence factor of Staphylococcus aureus. However, the physiological role of the nuclease has not been fully characterized. The current study observed that biofilm development could be prevented in staphylococcal nuclease-producing strains of S. aureus; however, when the nucl gene was knocked out, the ability to form a biofilm significantly increased. Scanning electron and confocal scanning laser microscopy were used to evaluate the role of the nucl gene in biofilm formation. Moreover, the nucl gene product, staphylococcal nuclease, and re- combinant NUC1 protein were found to have a visible effect on other biofilm-forming bacteria, such as Pseudomonas aeru- ginosa, Actinobacillus pleuropneurnoniae, and Haernophilus parasuis. The current study showed a direct relationship between staphylococcal nuclease production and the prevention of biofilm development. The findings from this study underscore the important role of staphylococcal nuclease activity to prevent biofilm formation in S. aureus. They also provided evidence for the biological role of staphylococcal nucleases in other organisms. 展开更多
关键词 biofilm formation nucl gene staphylococcal nuclease Staphylococcus aureus
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Effect of direct quenching on microstructure and mechanical properties of medium-carbon Nb-bearing steel 被引量:7
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作者 Ying-li ZHAO Jie SHI +2 位作者 Wen-quan CAO Mao-qiu WANG Gang XIE 《Journal of Zhejiang University-Science A(Applied Physics & Engineering)》 SCIE EI CAS CSCD 2010年第10期776-781,共6页
The influence of direct quenching (DQ) on microstructure and mechanical properties of 0.19C-1.7Si-1.0 Mn-0.05Nb steel was studied. The microstructure and mechanical properties of reheat quenched and tempered (RQ&T... The influence of direct quenching (DQ) on microstructure and mechanical properties of 0.19C-1.7Si-1.0 Mn-0.05Nb steel was studied. The microstructure and mechanical properties of reheat quenched and tempered (RQ&T) steel plate were compared with those of direct quenched and tempered (DQ&T) steel plates which were hot rolled at different finish rolling tem-peratures (1173 K and 1123 K), i.e., recrystallization-controlled-rolled direct-quenched (RCR&DQ) and controlled-rolled direct-quenched (CR&DQ), respectively. The strengths generally increased in the following order: RQ&T<RCR&DQ&T< CR&DQ&T. Strength differences between the CR&DQ&T and RQ&T conditions as high as 14% were observed at the tempered temperature of 573 K. The optical microscopy of the CR&DQ&T steel showed deformed grains elongated along the rolling direction, while complete equiaxed grains were visible in RQ&T and RCR&DQ&T steels. Transmission electron microscopy (TEM) and electron backscattering diffraction (EBSD) of the DQ steels showed smaller block width and higher density of dislocations. Inheritance of austenite deformation substructure by the martensite and differences in martensite block width were ruled out as major causes for the strength differences between DQ and RQ steels. 展开更多
关键词 Direct quenching (DQ) BLOCK Mechanical properties Electron backscattering diffraction (EBSD) Nb steel
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Design and performance test of a two-axis fast steering mirror driven by piezoelectric actuators 被引量:4
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作者 方楚 郭劲 +3 位作者 杨国庆 姜振华 徐新行 王挺峰 《Optoelectronics Letters》 EI 2016年第5期333-336,共4页
A novel design of a two-axis fast steering mirror(FSM) with piezoelectric actuators is proposed for incoherent laser beam combination. The mechanical performance of the FSM is tested. The results show that the tilting... A novel design of a two-axis fast steering mirror(FSM) with piezoelectric actuators is proposed for incoherent laser beam combination. The mechanical performance of the FSM is tested. The results show that the tilting range of the mirror is about 4 mrad, and the 1st-order resonance frequency is about 250 Hz. A self-designed grating encoder is taken as the sensor, which ensures the optimal precision of 10 μrad. The novel mechanical design can meet the requirement of engineering in incoherent laser beam combination. 展开更多
关键词 mirror piezoelectric grating steering encoder requirement scanner absolute elliptical inertia
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Implementation of Positive Operator-Valued Measure in Passive Faraday Mirror Attack
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作者 王卫龙 高明 马智 《Communications in Theoretical Physics》 SCIE CAS CSCD 2015年第3期296-302,共7页
Passive Faraday-mirror(PFM) attack is based on imperfect Faraday mirrors in practical quantum cryptography systems and a set of three-dimensional Positive Operator-Valued Measure(POVM) operators plays an important rol... Passive Faraday-mirror(PFM) attack is based on imperfect Faraday mirrors in practical quantum cryptography systems and a set of three-dimensional Positive Operator-Valued Measure(POVM) operators plays an important role in this attack.In this paper,we propose a simple scheme to implement the POVM in PFM attack on an FaradayMichelson quantum cryptography system.Since the POVM can not be implemented directly with previous methods,in this scheme it needs to expand the states sent by Alice and the POVM operators in the attack into four-dimensional Hilbert space first,without changing the attacking effect by calculation.Based on the methods proposed by Ahnert and Payne,the linear-optical setup for implementing the POVM operators is derived.At last,the complete setup for realizing the PFM attack is presented with all parameters.Furthermore,our scheme can also be applied to realize PFM attack on a plug-and-play system by changing the parameters in the setup. 展开更多
关键词 Faraday mirrors passive Faraday mirror attack POVM linear optics
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