34 results on '"Guo, Junjie"'
Search Results
2. Diversity analysis of leaf endophytic fungi and rhizosphere soil fungi of Korean Epimedium at different growth stages
- Author
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Chen Jiawen, Wu Yuan, Zhuang Xin, Guo Junjie, Hu Xing, and Xiao Jinglei
- Subjects
Genetics ,Applied Microbiology and Biotechnology ,Microbiology - Abstract
Background Rhizosphere fungi and endophytic fungi play key roles in plant growth and development; however, their role in the growth of Epimedium koreanum Nakai at different stages remains unclear. Here, we used the Illumina MiSeq system, a high-throughput sequencing technology, to study the endophytic fungi and rhizosphere microbiome of Korean Epimedium. Results Epimedium koreanum Nakai rhizosphere soil and leaves had highly diverse fungal communities during the growth process. The relative abundance of soil fungi in the rhizosphere stage was higher than that of leaf endophytic fungi in the early growth stage, but the overall abundance was basically equal. Sebacina is a significantly divergent fungal genera, and Sebacina sp. are present among leaf fungi species in the rhizosphere soil of Epimedium koreanum Nakai. Sebacina sp. can move to each other in rhizosphere soil fungi and leaf endophytes. VIF (variance inflation factor) analysis showed that soluble salt, whole nitrogen, alkaline lysis nitrogen, whole phosphorus, total potassium, and fast-acting potassium are useful environmental factors for rhizosphere soil and leaf endophytic fungi: potassium, total nitrogen, whole phosphorus, and three environmental factors were significantly and positively associated with the relative abundance of Sebacina sp. Conclusions (1) This study is the first to clarify the species diversity of fungi in Epimedium koreanum Nakai leaf and rhizosphere soil. (2) Different fungal communities of rhizosphere soil fungi and leaf endophytic fungi at different growth stages of Epimedium koreanum Nakai were examined. (3) Sebacina sp. can move to each other between rhizosphere soil fungi and leaf endophytic fungi. (4) Nitrogen, phosphorus and potassium elements in the environment have a significant positive effect on the relative abundance of Sebacina sp.
- Published
- 2022
3. A Conflict Resolution Scheme in Intent-Driven Network
- Author
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Jiaming Zhang, Cao Lihui, Li Ruixing, Xiaoming Zhu, Jiao Libin, Guo Junjie, Chungang Yang, and Xinru Mi
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Scheme (programming language) ,Computer science ,Network security ,business.industry ,Reliability (computer networking) ,Knowledge engineering ,Computer security ,computer.software_genre ,Security policy management ,Network management ,Scalability ,Conflict resolution ,business ,computer ,computer.programming_language - Abstract
Intent-Driven Network (IDN) is a promising networking paradigm that makes network management autonomous, flexible, and scalable. IDN reduces the difficulty of network management by translating the declarative user intent to machine-executable policies. Although IDN brings considerable advantages to network management, there exist novel security policy management problems, such as security intent-aware policy conflict. Although there are already some conflict resolution schemes, they are less automated and more energy-consuming. We present a Quadruple-based Intent Conflict Resolution (QICR) engine to address the intent conflict in IDN in this paper. The QICR implements an intent conflict resolution scheme to convert potentially conflicting intents to conflict-free intents. We implement the QICR engine in a simulation platform and demonstrate the proposed conflict resolution scheme's effectiveness.
- Published
- 2021
4. Foliar morphology and spatial distribution in five-year-old plantations of Betula alnoides
- Author
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Jie Zeng, Sebastian Hein, Wang Huan, Chunsheng Wang, Zhao Zhigang, and Guo Junjie
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0106 biological sciences ,Betula alnoides ,Specific leaf area ,Crown (botany) ,Sowing ,Forestry ,Management, Monitoring, Policy and Law ,Biology ,Spatial distribution ,010603 evolutionary biology ,01 natural sciences ,Horticulture ,Dry weight ,Leaf size ,Leaf area index ,010606 plant biology & botany ,Nature and Landscape Conservation - Abstract
Foliage spatial distribution and morphological variation within crowns reflect the adjustment of a tree to acclimatise to different microenvironments within crowns and stands. They play important roles in the light use efficiency, carbon assimilation and photosynthesis capacity of the whole tree. In this study, leaf quantity and size at the tree and crown layer levels, and leaf morphology across crown layers, sectors and zones, from 18 trees were investigated in five-year-old Betula alnoides plantations with six planting densities. The results showed that the vertical distributions of leaf number, leaf area index, cumulative branch cross sectional area and leaf area and their ratios were skewed towards the upper crown layers, especially for high planting densities. There was a tendency for leaf size (leaf length, width, perimeter and area) and leaf dry mass to increase from lower to upper crown layer and also from the inner to outer crown zones. The leaf shape factor was larger, and the ratio of leaf length to width and specific leaf area were much smaller, for leaves in the outer and upper crown positions. Leaves in the southern and eastern sectors were smaller than those in the northern and western sectors, but leaf length to width ratio, leaf shape factor and specific leaf area did not differ significantly among four crown sectors. In addition, planting density had no significant effect on leaf related traits at the individual tree and crown layer levels, and leaf morphology also did not vary regularly with planting density, but the specific leaf area was significantly negatively correlated with planting density. However, the interactions between planting density and crown layer, crown sector and crown zone, and among planting density, crown layer and crown zone, were significant. The findings confirmed the acclimation of leaf distribution and morphology to different microenvironments, and provided baseline information for plantation management of B. alnoides and other valuable hardwood species in southern China and other regions with similar climate conditions.
- Published
- 2019
5. Optically detected magnetic resonance of nitrogen-vacancy centers in vertical diamond Schottky diodes
- Author
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Muhammad Hafiz bin Abu Bakar, Aboulaye Traore, Guo Junjie, Toshiharu Makino, Masahiko Ogura, Satoshi Yamasaki, and Takeaki Sakurai
- Subjects
General Engineering ,General Physics and Astronomy - Abstract
Diamond solid-state devices are very attractive to electrically control the charge state of nitrogen-vacancy (NV) centers. In this work, p-type vertical diamond Schottky diodes (VDSDs) are introduced as a platform to electrically control the interconversion between the neutral charge NV (NV0) and negatively charged NV (NV−) centers. The photoluminescence of NV centers generated by ion implantation in VDSDs shows an increase in NV−zero phonon line (ZPL) and phonon sideband intensities with reverse voltage, whereas the NV0ZPL intensity decreases. Thus, NV centers embedded in VDSDs are converted into NV−under reverse bias voltage. Moreover, the optically detected magnetic resonance (ODMR) of NV−exhibits an increase in the ODMR contrast with reverse bias voltage and splitting of the resonance dips. Since no magnetic field is applied, the dip splitting in the ODMR spectrum is ascribed to the Stark effect induced by the interaction of NV−with the electric field existing within the depletion region of VDSDs.
- Published
- 2022
6. Autonomy-oriented proximity mobile social network modeling in smart city for emergency rescue
- Author
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Zhao Chunxiao and Guo Junjie
- Subjects
Computer Networks and Communications ,Electronic computers. Computer science ,General Engineering ,QA75.5-76.95 - Abstract
Nearest neighbor mobile social network means that movers approaching in position communicate through their social sensors, which is called Proximity Mobile Social Network. Proximity Mobile Social Network can provide more social and business opportunities for users. To carry out disaster relief work in post-disaster environment, we need to collect incident information during the search process and report to the sink in time. Proximity Mobile Social Network provides flexible systems for emergency handling and disaster relief. Therefore, how to find a better data forwarding and routing strategy is the key problem of post-disaster rescue, and the research of user mobility model is the basis of the above problems. This article presents an Autonomy-Oriented Proximity Mobile Social Network modeling for emergency rescue in smart city, which simulates the network operating environment. First, we verify the performance of Autonomy-Oriented Proximity Mobile Social Network model in terms of self-organization, scale-free, aggregation, and community structure. Then, the rescue efficiency is discussed through the coverage of mobile sensors. Finally, performance of the routing strategy based on Autonomy-Oriented Proximity Mobile Social Network model is analyzed, and the effectiveness of the method is proved.
- Published
- 2021
7. Morphometric study confirms the presence of only Vatica mangachapoi on Hainan Island, China
- Author
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Shuai-Bin Shang, Guo Junjie, and Jie Zeng
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0106 biological sciences ,education.field_of_study ,Dipterocarpaceae ,Vatica mangachapoi ,Range (biology) ,Population ,Forestry ,02 engineering and technology ,Subspecies ,Biology ,021001 nanoscience & nanotechnology ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,Herbarium ,Genus ,Botany ,Vatica ,0210 nano-technology ,education - Abstract
To date only one species of the genus Vatica Linn. (Dipterocarpaceae) has been identified, and a subspecies and three varieties have been reported on Hainan Island, China. However, it remained controversial whether the species was Vatica mangachapoi or a new species Vatica hainanensis, and whether the subspecies or varieties are taxonomically valid. We evaluated here morphometric variations of 133 trees collected from nine populations and herbarium specimens of Vatica spp. using 16 traits of leaf and fruit. Among these, leaf traits varied more within and among populations than did fruit traits. Four traits of ratios were more stable than directly-measured traits within and among populations. The ranges of lamina length, lamina width and height of maximum lamina width point were the greatest among the 16 traits, while number of lateral veins varied least among the 12 directly-measured traits. Measurements from all 9 populations overlapped for each morphological trait, and variation of each trait was continuous among both individuals and populations. The range of variation did not distinguish any specimen from V. mangachapoi as described in the flora of Southeast Asia. By cluster analysis, individuals of each population as well as specimens of each variety formed no distinct clusters. The published varieties thus were characterized by no distinguishing variations in comparison with the nine sampled populations. In conclusion, the new species V. hainanensis as well as the subspecies and varieties were not supported by our comparisons, and only V. mangachapoi without any subspecies or varieties occurs on Hainan Island, China.
- Published
- 2017
8. Growth and nutrient dynamics of Betula alnoides seedlings under exponential fertilization
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Lin Chen, Bernard Dell, D. Xu, Zhao Zhigang, Jie Zeng, Chunsheng Wang, and Guo Junjie
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040101 forestry ,Betula alnoides ,biology ,Phosphorus ,chemistry.chemical_element ,Forestry ,04 agricultural and veterinary sciences ,engineering.material ,biology.organism_classification ,Human fertilization ,Nutrient ,Agronomy ,chemistry ,Dry weight ,Seedling ,040103 agronomy & agriculture ,engineering ,0401 agriculture, forestry, and fisheries ,Dry matter ,Fertilizer - Abstract
Betula alnoides is a fast-growing hardwood species grown in large plantations in Southeast Asia and South China. Nitrogen requirements for producing robust seedlings, growth and nutrient dynamics were investigated using exponential fertilization treatments. Root collar diameter, height, dry mass and nutrient contents of seedlings increased exponentially in all fertilization treatments as time progressed. Moreover, with water soluble fertilizer (Plant Products plus microelements N–P2O5–K2O: 20–20–20), 300 mg N seedling−1 was adequate. Vector analysis revealed that P was the most responsive nutrient element, followed by N and K. Dilutions of N and K were evident in the plants without N addition, which induced initial P sufficiency and then luxury consumption probably due to the antagonistic interaction between N and P. However, deficiencies of N, P and K were mostly observed in all exponential regimes during the experiment because seedling growth rate exceeded nutrient uptake rate, inferring that further study on improving the nutrient uptake efficiency is needed. Analysis of relationships among nutrient supply, dry mass, N content and N concentration demonstrated that 100–400 mg N seedling−1 induced sufficiency to luxury consumption of nitrogen without significant change in dry mass, and 400 mg N seedling−1 is recommended to apply for nutrient loading of seedlings before outplanting. The findings will help improve seedling quality and enhance the production of robust seedlings for plantation forestry of this species.
- Published
- 2017
9. Crown and branch attributes of mid-aged Betula alnoides plantations in response to planting density
- Author
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Jie Zeng, Zhao Zhigang, Sebastian Hein, Guo Junjie, Chunsheng Wang, and Ji Zeng
- Subjects
0106 biological sciences ,Betula alnoides ,Botany ,Crown (botany) ,Sowing ,Forestry ,Biology ,010603 evolutionary biology ,01 natural sciences ,010606 plant biology & botany - Abstract
Both crown and branch characteristics greatly affect tree growth and timber quality, and their development is closely related to planting density (PD). Here crown and branch attributes of Betula al...
- Published
- 2016
10. Effect of temperature on the development and reproduction of Cryptophlebia ombrodelta (Lower) (Lepidoptera: Tortricidae)
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郭俊杰 Guo Junjie, 王胜坤 Wang Shengkun, 赵志刚 Zhao Zhigang, 王春胜 Wang Chunsheng, 王欢 Wang Huan, and 王晨彬 Wang Chenbin
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Lepidoptera genitalia ,Tortricidae ,Ecology ,media_common.quotation_subject ,Cryptophlebia ombrodelta ,Zoology ,Biology ,Reproduction ,biology.organism_classification ,Ecology, Evolution, Behavior and Systematics ,media_common - Published
- 2019
11. Spatial patterns and seasonal dynamics of foliar nutrients in 5-year-old Betula alnoides plantations
- Author
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Zhao Zhigang, Chunsheng Wang, Guo Junjie, Jie Zeng, and Wang Huan
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0106 biological sciences ,Betula alnoides ,Phosphorus ,Crown (botany) ,chemistry.chemical_element ,Sowing ,Forestry ,Management, Monitoring, Policy and Law ,Biology ,010603 evolutionary biology ,01 natural sciences ,Resorption ,Nutrient ,chemistry ,Agronomy ,Soil fertility ,Pruning ,010606 plant biology & botany ,Nature and Landscape Conservation - Abstract
Spatial distribution and season-induced variations in foliar nutrients of tree crowns play key roles in growth, and nutrient retranslocation and resorption from leaves are important mechanisms for trees to cope with sites of diversified fertility. Seasonal dynamics and spatial patterns of foliar macronutrients (Nitrogen (N), Phosphorus (P) and Potassium (K)) as well as nutrient retranslocation and resorption in a series of crown layers were examined in 5-year-old Betula alnoides plantations using a spacing trial (2500 (2 m × 2 m, spacing), 1667 (2 m × 3 m), 1250 (2 m × 4 m), 1111 (3 m × 3 m), 833 (3 m × 4 m) and 625 (4 m × 4 m) stems·ha−1) in south China. Significant effects of planting density on foliar nutrient concentrations and nutrient retranslocation and resorption were absent during a whole seasonal cycle or in each season. Both foliar total P and K concentrations increased significantly with increasing crown depth, whereas an obvious trend was not observed for foliar total N concentration. The season with the lowest foliar nutrient concentration varied with the elements, i.e. summer (Jul) for N, winter (Jan) for P and spring (Apr) for K, whereas the highest was observed in autumn (Oct) for all these macronutrient elements. Among crown layers, differences in nutrient concentrations were much lower in the high growth seasons from October to April than those in other seasons. There were significant differences among crown layers in N and P retranslocation efficiency rather than in nutrient resorption efficiency. Significant differences were absent in both retranslocation and resorption efficiencies of K. The highest nutrient retranslocation efficiency was found in the crown layer 2–3 m above ground level for N and 3–4 m for P. The absence of considerable differences among spacing treatments and crown layers mentioned above might be due to the weak early intra-specific competition induced by planting density, soil fertility or fertilization and nutrient demands of this species. These findings could provide suggestions for implementing proper pruning treatments, improving fertilization regimes and other related forest managements for B. alnoides and even other valuable timber species in the tropical and warm sub-tropical regions.
- Published
- 2021
12. Branch occlusion and discoloration of Betula alnoides under artificial and natural pruning
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Jie Zeng, Zhao Zhigang, Chunsheng Wang, Guo Junjie, and Sebastian Hein
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Betula alnoides ,010504 meteorology & atmospheric sciences ,Insertion angle ,fungi ,Forestry ,04 agricultural and veterinary sciences ,Management, Monitoring, Policy and Law ,01 natural sciences ,Horticulture ,Knot (unit) ,stomatognathic system ,nervous system ,Occlusion ,040103 agronomy & agriculture ,0401 agriculture, forestry, and fisheries ,Pruning ,Tree species ,Silviculture ,0105 earth and related environmental sciences ,Nature and Landscape Conservation ,Mathematics - Abstract
Knot-related defects are important criteria for timber grading of valuable tree species. Clear-wood production through pruning has been an important issue in silviculture and forest management. In this study, knot attributes, branch occlusion and discoloration under natural and artificial pruning were investigated in a 10-year-old Betula alnoides plantation to determine the effectiveness of artificial pruning in mitigating knot-related defects. The dataset contained 270 occluded branches sampled from 30 artificially-pruned trees and 284 from 30 trees under natural pruning. Linear and generalized linear mixed-effect models were constructed to reveal the differences in factors influencing branch occlusion, knot size, and discoloration between natural and artificial pruning treatments. The mixed-effect models indicated that the most important factor in predicting branch occlusion time, dead knot radius, total knot radius and discoloration length was branch diameter for artificial pruning and dead branch stub length for natural pruning. The dead branch stub length was also closely and positively correlated with branch diameter under natural pruning. Branch occlusion time was negatively correlated with stem diameter growth rate during the period of branch occlusion while discoloration length was positively correlated with branch occlusion time for both treatments. In addition, acute branch insertion angle increased the size of dead knot and discoloration. It was concluded that artificial pruning promotes faster branch occlusion, reduces knot sizes and does not lead to stem discolorations, and should hence be applied in the plantation management of this species.
- Published
- 2016
13. Effect of Cylindrical Mirror Rotation on the Far-Field Spot of a Shaping Beam
- Author
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郭建增 Guo Jianzeng, 任晓明 Ren Xiaoming, 李卿 Li Qing, 郭俊杰 Guo Junjie, and 刘现魁 Liu Xiankui
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Physics ,Optics ,business.industry ,Near and far field ,Electrical and Electronic Engineering ,business ,Rotation ,Atomic and Molecular Physics, and Optics ,Beam (structure) ,Electronic, Optical and Magnetic Materials - Published
- 2020
14. Simulating the heartwood formation process of Erythrophleum fordii in South China
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Zhao Zhigang, Chunsheng Wang, Jie Zeng, and Guo Junjie
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Erythrophleum fordii ,Radial growth ,South china ,Botany ,Natural forest ,Endangered species ,Xylem ,Forestry ,Biology ,biology.organism_classification ,Rosewood - Abstract
We studied the formation of heartwood in Erythrophleum fordii Oliv., an endangered rosewood species, by cross-section analysis on 52 stumps aged 28–57 years and arbitrarily sampled from natural forests in South China. Width and area of heartwood were positively correlated with age and xylem width (XW), and were independent of annual radial growth. The proportions of heartwood and sapwood areas were equal at about 40 years. The heartwood formation process was simulated by linear regression of age and XW.
- Published
- 2015
15. Effects of Protein in Wheat Flour on Retrogradation of Wheat Starch
- Author
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Guo Junjie, Wang Danli, Zhu Jiaran, Lian Xijun, and Li Lin
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Magnetic Resonance Spectroscopy ,food.ingredient ,Glutens ,Globulin ,Retrogradation (starch) ,Starch ,Flour ,Wheat flour ,Gliadin ,Hydrolysis ,chemistry.chemical_compound ,food ,Albumins ,Food science ,Resistant starch ,Triticum ,Calorimetry, Differential Scanning ,biology ,Temperature ,food and beverages ,Globulins ,Biochemistry ,chemistry ,biology.protein ,alpha-Amylases ,Alpha-amylase ,Food Science - Abstract
Albumins, globulins, gliadins, and glutenins were isolated from wheat flour and the effects of those proteins on retrogradation of wheat starch were investigated. The results showed that only glutenins retarded retrogradation of wheat starch and other 3 proteins promoted it. The results of IR spectra proved that no S-S linkage formed during retrogradation of wheat starch blended with wheat proteins. Combination of wheat starch and globulins or gliadins through glucosidic bonds hindered the hydrolysis of wheat starch by α-amylase. The melting peak temperatures of retrograded wheat starch attached to different proteins were 128.46, 126.14, 132.03, 121.65, and 134.84 °C for the control with no protein, albumins, glutenins, globulins, gliadins groups, respectively, and there was no second melting temperature for albumins group. Interaction of wheat proteins and starch in retrograded wheat starch greatly decreased the endothermic enthalpy (△H) of retrograded wheat starch. Retrograded wheat starch bound to gliadins might be a new kind of resistant starch based on glycosidic bond between starch and protein.
- Published
- 2014
16. Influence of Velocity on Ultrasonic Probing of Orchard Tree Profile
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Zhai Changyuan, Ma Wei, Wang Xiu, Guo Junjie, and Xu Sha
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Tree (data structure) ,Acoustics ,Electronic engineering ,Environmental science ,Ultrasonic sensor ,Electrical and Electronic Engineering ,Orchard ,Atomic and Molecular Physics, and Optics - Published
- 2013
17. Spatiotemporal dynamics of seed rain in natural forest of Betula alnoides in Jingxi County, Guangxi, China
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Lin Kai-Qin, OU Jing-Li, Zeng Jie, Zhao Zhigang, and Xu Da-Ping, Guo Junjie, and Sha Er
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Betula alnoides ,Ecology ,Agroforestry ,Natural forest ,Plant Science ,Biology ,China ,Ecology, Evolution, Behavior and Systematics - Published
- 2013
18. Assembly error inspection of ICF micro-capsule
- Author
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Guo Junjie, Xu Xiaojie, and Fei Zhigen
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Optics ,Materials science ,Mathematical model ,business.industry ,Plasma confinement ,Capsule ,Semiconductor device ,Electrical and Electronic Engineering ,business ,Inertial confinement fusion ,Atomic and Molecular Physics, and Optics - Published
- 2013
19. Application of compound measuring method with laser and CCD to sphericity error detection of ICF target
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Ma Xiaojun, Guo Junjie, Fei Zhigen, and Gao Dangzhong
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Physics ,Optics ,business.industry ,law ,Electrical and Electronic Engineering ,Error detection and correction ,business ,Laser ,Atomic and Molecular Physics, and Optics ,Sphericity ,law.invention - Published
- 2011
20. Branch Development of Five-Year-Old Betula alnoides Plantations in Response to Planting Density
- Author
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Chunsheng Wang, Sebastian Hein, Jie Zeng, Cheng Tang, Guo Junjie, and Zhao Zhigang
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0106 biological sciences ,South china ,010504 meteorology & atmospheric sciences ,branch quantity ,planting density ,wood quality ,01 natural sciences ,mixed-effects models ,Betula alnoides ,Hectare ,young plantation ,0105 earth and related environmental sciences ,Mathematics ,Wood production ,fungi ,Crown (botany) ,branch morphology ,food and beverages ,Sowing ,Forestry ,lcsh:QK900-989 ,Horticulture ,lcsh:Plant ecology ,Mixed effects ,Pruning ,010606 plant biology & botany - Abstract
Branch development in the lower part of stem is critical to both early stem growth and wood quality of the most valuable section of tree, and its regulation through planting density has always been greatly concerned. Here the effect of planting density on branch development was examined in a five-year-old plantation of Betula alnoides with six planting densities (625, 833, 1111, 1250, 1667, and 2500 stems per hectare (sph)) in Guangdong Province, South China. Branch quantity (number, proportion, and density), morphology (diameter, length, and angle), position (height and orientation), and branch status (dead or alive) were investigated for 54 dominant or co-dominant trees under six treatments of planting density after the growth of each tree was measured. Factors influencing branch development were also explored by mixed modelling. The results showed that the mean tree heights of 1250 and 1667 sph treatments were higher than those of other planting density treatments. The quantity of live branches decreased with increasing planting density. However, planting density had no significant effect on the number of all branches, and there existed no remarkable difference in branch number and proportion among four orientations. As for branch morphology, only the largest branch diameter had a significantly negative correlation with planting density. In addition, high planting density significantly increased the height of the largest branch within the crown. Mixed effects models indicated that branch diameter, length, and angle were closely correlated with each other, and they were all in positively significant correlation to the branch height at the stem section below six meters. It was concluded that properly increasing planting density will promote natural pruning, improve early branch control, and be beneficial for wood production from the most valuable section of the stem.
- Published
- 2018
21. Progress in Measurement with Picometer Resolution and Subdivision Technique
- Author
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郭俊杰 Guo Junjie, 王昭 Wang Zhao, 蒋志雄 Jiang Zhi-xiong, and 汤善治 Tang Shan-zhi
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Physics ,Interferometry ,Optics ,business.industry ,Resolution (electron density) ,Picometre ,High resolution ,business ,Atomic and Molecular Physics, and Optics ,Subdivision - Abstract
The domestic and foreign progress of picometer resolution measurements were reviewed.Typtical methods for measurement with high resolution(picometer resolution) were introduced,and the progress of picometer measurements was presented.The principles and corresponding subdivision techiniques were studied.Then,two novel measurements were proposed and analyzed.The multiple reflection interferometer was analyzed.It has the advantages of higher resoultion and more simplicity deivce than X-ray interferometer,which provide a good future in the fields of spectroscopy and high-precision measurement.
- Published
- 2010
22. Gigahertz Dielectric Polarization of Single-atom Niobium Substituted in Graphitic layers
- Author
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Zhang, Xuefeng, Guo, Junjie, Guan, Pengfei, Qin, Gaowu, and Pennycook, Stephen J.
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Condensed Matter - Materials Science ,Materials Science (cond-mat.mtrl-sci) ,FOS: Physical sciences - Abstract
We have synthesized two Nb@C composites with an order of magnitude difference in the density of single-atom niobium substituted into graphitic layers. The concentration and sites of single-atom Nb are identified using aberration-corrected scanning transmission electron microscopy and density functional theory. Comparing the complex permittivity spectra show that the representative dielectric resonance at ~16 GHz originates from the intrinsic polarization of single-atom Nb sites, confirmed by theoretical simulations. The single-atom dielectric resonance represents the physical limit of the electromagnetic response of condensed matter, and thus might open up a new avenue for designing electromagnetic wave absorption materials. Single-atom resonance also has important implications in understanding the correlation between the macroscopic dielectric behaviors and the atomic-scale structural origin.
- Published
- 2015
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23. Structure Design of Multi-function Ball Screw Measuring Device and Research on Testing Scheme
- Author
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Guo Junjie, Haitao Li, Wang Xing, and Du Hongfeng
- Subjects
Scheme (programming language) ,Engineering ,Bearing (mechanical) ,business.industry ,Function (mathematics) ,Structural engineering ,Ball screw ,law.invention ,Test (assessment) ,Acceleration ,law ,business ,computer ,Friction torque ,computer.programming_language ,Block (data storage) - Abstract
A multi-function ball screw measuring device is developed, which can achieve most of the parameter testing of ball screw like geometric accuracy, positional accuracy, reverse clearance, speed and acceleration, friction torque, preload, fatigue properties, temperature rise and so on. According to the supporting features of parameters testing, we can divide the test bed into two categories: double dead center test bed and double bearing seat test bed. The former is used to do low speed and high precision test experiments, and the latter is used to do high speed and heavy load test experiment. By the means of reasonable structure design and simply assembly, we can conduct these two kinds of test on the ball screw measuring device. In this way, not only the cost is cut down, but also the comprehensive and reliable evaluation for ball screw will be obtained. In this paper, detail introduction of test platform building and test program for different test parameters is given. The content of paper is divided into two parts, the first part describes the overall structure design, double dead center test platform building and geometric accuracy test program, the second part describes double bearing block test platform building and relevant test programs.
- Published
- 2015
24. Study on the Test Scheme of Ball Screw Dynamic Characteristic Parameters
- Author
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Jindong Wang, Du Hongfeng, Guo Junjie, and Haitao Li
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Scheme (programming language) ,Computer science ,Control theory ,Ball screw ,computer ,computer.programming_language ,Test (assessment) - Published
- 2015
25. Novel hydroxybutyl chitosan nanoparticles for siRNA delivery targeting tissue factor inhibits proliferation and induces apoptosis in human vascular smooth muscle cells
- Author
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Pan Wang, Dan Li, Yi An, Xuexun Li, Wan Kang, Yongfang Guo, Junhua Ge, Guo Junjie, Leng Min, Jian Li, and Yunlong Wang
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Cancer Research ,Vascular smooth muscle ,Cell ,Myocytes, Smooth Muscle ,Apoptosis ,Gene delivery ,Biology ,Biochemistry ,Thromboplastin ,Tissue factor ,Annexin ,cardiovascular disease ,Genetics ,medicine ,Humans ,RNA, Small Interfering ,gene delivery ,Molecular Biology ,Chitosan ,cell apoptosis ,Cell growth ,hydroxybutyl chitosan ,Transfection ,Articles ,tissue factor ,Cell biology ,medicine.anatomical_structure ,cell proliferation ,Oncology ,siRNA ,Immunology ,Molecular Medicine ,Nanoparticles ,RNA Interference ,vascular smooth muscle cell - Abstract
Chitosan, a polysaccharide isolated from shrimp and other crustacean shells, has been widely investigated for DNA and siRNA delivery. Despite substantial effort having been made to improve chitosan as a non-viral gene delivery vector, the application is severely limited by its poor solubility under physiological conditions. Hydroxybutyl chitosan (HBC), a modified chitosan, is soluble under neutral conditions. Tissue factor (TF) is involved in the pathogenesis of cardiovascular diseases by promoting thrombus formation and inducing the migration and proliferation of vascular smooth muscle cells. Targeting TF is an attractive therapeutic strategy for cardiovascular diseases. In the present study, the use of HBC for the transfer of TF-siRNAs into human umbilical vein smooth muscle cells (HUVSMCs) was investigated, and the effects of TF knockdown on cell proliferation and apoptosis were examined. HBC/siRNA nanoparticles were produced by mixing HBC and siRNA solutions with the assistance of tripolyphosphate buffer. The transfection efficiency with these nanoparticles was 74±2.5%, which was determined using a fluorescence-labeled siRNA under fluorescence microscopy. The delivery of HBC/TF-siRNA resulted in reductions in the production of cellular and soluble TF protein in HUVMSCs, which were measured using western blotting and enzyme-linked immunosorbent assay, respectively. TF knockdown led to inhibited cell proliferation, as assessed using a Cell Counting Kit-8 assay, and increased cell apoptosis, determined using Annexin V-fluorescein isothiocyanate staining. These findings suggested that HBC may be a promising vector for siRNA delivery, and that in vivo HBC/siRNA nanoparticle delivery targeting TF may be a potential option for the treatment of cardiovascular diseases, which warrants further investigation.
- Published
- 2014
26. Twenty Microsatellite Markers for the EndangeredVatica mangachapoi(Dipterocarpaceae)
- Author
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Jie Zeng, Shuai-Bin Shang, Guo Junjie, Chunsheng Wang, and Zhao Zhigang
- Subjects
0106 biological sciences ,0301 basic medicine ,Conservation genetics ,Genetics ,Genetic diversity ,Dipterocarpaceae ,biology ,Vatica mangachapoi ,Endangered species ,Zoology ,Plant Science ,biology.organism_classification ,010603 evolutionary biology ,01 natural sciences ,Gene flow ,03 medical and health sciences ,030104 developmental biology ,Genetic marker ,Microsatellite ,Ecology, Evolution, Behavior and Systematics - Abstract
Premise of the study: Microsatellite markers were developed for Vatica mangachapoi (Dipterocarpaceae), an endangered species indigenous to Southeast Asia and southern China. Methods and Results: Twenty microsatellite markers, including 12 polymorphic markers, were identified from V. mangachapoi using high-throughput sequencing. Polymorphism at each marker was evaluated using 87 individuals from three natural populations. The number of alleles per polymorphic locus ranged from six to 15, and the observed and expected heterozygosity varied from 0.000 to 0.926 and from 0.177 to 0.864, respectively. These markers were transferred successfully to the endangered species V. guangxiensis. Conclusions: These markers may be used to investigate the genetic diversity and gene flow of V. mangachapoi and V. guangxiensis.
- Published
- 2017
27. A digital management system of part processing parameter based on UG
- Author
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Guo Junjie, Yue Jing, Shao Wei, Wu Ying, and Liu Chong
- Subjects
Computer science ,Management system ,Systems engineering - Published
- 2014
28. Identification of geometric deviations inherent to multi-axis machine tools based on the pose measurement principle
- Author
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Li Haitao, Guo Junjie, He Xinrong, Deng Yufen, and Wang Jindong
- Subjects
0209 industrial biotechnology ,business.product_category ,Applied Mathematics ,02 engineering and technology ,Fixed point ,01 natural sciences ,Machine tool ,010309 optics ,Identification (information) ,020901 industrial engineering & automation ,Laser tracker ,Position (vector) ,Control theory ,Measuring principle ,0103 physical sciences ,Calibration ,Numerical control ,business ,Instrumentation ,Engineering (miscellaneous) ,Algorithm ,Mathematics - Abstract
The laser tracker is an effective instrument for measuring 3D relative displacement in a work volume because its attitude can be freely changed. This paper presents a novel principle to realize the precise calibration of a numerical control (NC) machine tool accurately and quickly; this is the 'pose measurement principle', for measuring errors. We also introduce an algorithm for identifying geometric deviations. A NC precise table mounted on a motion axis and a laser tracker are used for the coordinate determination of three fixed points to obtain the pose information of each motion axis, then calculate the pose deviations, and finally identify all the errors. For the error identification, first, according to the definition of geometric errors, we extend the concept of pose deviations, and represent the six geometric errors using a position deviation vector and attitude deviation vector. Next, we geometrically identify the three angular errors and linear errors in order; the error mathematical model for the linear axis and rotary axis are developed, respectively. Moreover, the validity of the calibration algorithm for the base station, measuring points and identification of errors are confirmed by simulations. In the end, the proposed method is applied to a three-axis NC milling machine tool and a rotary table, and then the geometric deviations are identified successfully in 3 h and 2.5 h, respectively. Comparative experiments by means of other instruments also agree well with the proposed method. Thus, the proposed method can be applied to the measurement of the multi-axis machine tool.
- Published
- 2016
29. A SUMO-Based Ontology of Expressway Network for Domain Knowledge Management
- Author
-
Guo Junjie and Tang Liantao
- Subjects
World Wide Web ,Decision support system ,Engineering ,business.industry ,Ontology-based data integration ,Information sharing ,Process ontology ,Suggested Upper Merged Ontology ,Upper ontology ,Domain knowledge ,business ,Intelligent transportation system - Abstract
This paper focuses on the domain knowledge management of expressway networks in Intelligent Transport Systems and develops ontology for them by reusing SUMO (Suggested Upper Merge Ontology) as the upper ontology. The approached ontology names SENO (SUMO-based Expressway Network Ontology) and consists of two parts, among which SENO Basic is the set of shared concepts and relations, whereas SENO Core divides key concepts and relations into several categories according to the pattern of semantic organization of information in expressway network. As illustrated in a case study, SENO can be instantiated to form a comprehensive semantic view of the domain knowledge to eliminate ambiguities among heterogeneous systems, and to better promote knowledge management and information sharing for expressway network.
- Published
- 2010
30. The Dimensionality Reduction of Feature Vectors by Generalized Cross Product
- Author
-
Chen Yanling, Guo Junjie, and Wei Jinwen
- Subjects
Artificial neural network ,Discriminant ,business.industry ,Robustness (computer science) ,Scatter matrix ,Dimensionality reduction ,Feature vector ,Pattern recognition ,Artificial intelligence ,Vector algebra relations ,Cross product ,business ,Mathematics - Abstract
Fisher?s discriminant requires the inverse operation of high-order within-class scatter matrix [Sw] in the dimensionality reduction of feature vectors. The results may be inaccurate if [Sw] is close to singular. This paper presents another classification-oriented mapping method for the dimensionality reduction of high-dimensional feature vectors, based on the generalized cross product of multi-vectors. The mapped feature vector is transformed into a cross matrix to generate a product vector, whose robustness depends on both the orthogonality and the norm-homogeneousness of the cross matrix, for pattern classification. To insure the within-class congregation and between-class separability of the mapping of feature vectors, it is proved that the optimum cross matrix is merely the orthonormalized basis of 2 reference vectors of sorted sample sets according to the robustness theorem of generalized cross product proposed in this paper. Numerical experiments showed that the proposed method has a better separability and better robustness of separability than Fisher?s method in the dimensionality reduction of high-dimension feature vectors.
- Published
- 2008
31. An Algorithm for Fast Circular Object Detection Based on Discrete Evolute Distribution
- Author
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Shi Enxiu, Zhang Tao, and Guo Junjie
- Subjects
Digital image ,Evolute ,Curve fitting ,Probability distribution ,Edge (geometry) ,Curvature ,Algorithm ,Object detection ,Edge detection ,Mathematics - Abstract
Based on the features of circle-like edge in digital image, an algorithm is presented in which the evolute of edge is calculated and from its distribution, the circles are located. The edge of target is first extracted and traced. Then the centers of curvature are calculated by least square fitting in fraction of edge and thus the evolute of edge is worked out. From the evolute distribution and the fitting degree, the circles can be recognized and their radii and centers are calculated. Experiments show that by the proposed method, circle-like target in image can be detected efficiently and accurately. And it is effective even for the distorted and deformed circles.
- Published
- 2008
32. Tribological property of onion-like fullerenes as lubricant additive
- Author
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Yao, Yanli, Wang, Xiaomin, Guo, Junjie, Yang, Xiaowei, and Xu, Bingshe
- Subjects
Diffraction ,Materials science ,Fullerene ,Mechanical Engineering ,Nanotechnology ,Tribology ,Condensed Matter Physics ,law.invention ,Electric arc ,Mechanics of Materials ,Transmission electron microscopy ,law ,General Materials Science ,Electron microscope ,Lubricant ,Composite material ,Tribometer - Abstract
Onion-like fullerenes (OLFs) were generated by arc discharge in water between pure graphite electrodes. The size and crystalline morphology of the generated OLFs were characterized by means of the high-resolution transmission electron microscopy and X-ray diffraction. Furthermore, OLFs were added to base lubricant and the tribological property of OLFs was investigated by using a four-ball type tribometer. The results indicated that the OLFs with diameter about 25 nm were of high degree graphitization. Good friction-reduction property at different additive concentration and applied load as lubricant additive was obtained. The scratches on the worn surfaces become slighter and more uniform with addition of OLFs to the base lubricant. In addition, the tribological mechanism of the sliding-bearing system was proposed.
- Published
- 2008
- Full Text
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33. Design and Analysis of the Polarization-Preserving Films for Rectangular Prism
- Author
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齐静雅 Qi Jingya, 王昭 Wang Zhao, 黄军辉 Huang Junhui, 郭俊杰 Guo Junjie, 李朝辉 Li Zhaohui, and 余宝 Yu Bao
- Subjects
Cuboid ,Optics ,Materials science ,business.industry ,Electrical and Electronic Engineering ,Polarization (waves) ,business ,Atomic and Molecular Physics, and Optics ,Electronic, Optical and Magnetic Materials - Published
- 2015
34. Expanded identification and characterization of mammalian circular RNAs
- Author
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Junjie U. Guo, Vikram Agarwal, Huili Guo, David P. Bartel, Massachusetts Institute of Technology. Computational and Systems Biology Program, Massachusetts Institute of Technology. Department of Biology, Whitehead Institute for Biomedical Research, Guo, Junjie U., Agarwal, Vikram, Guo, Huili, Bartel, David, and Lee Kong Chian School of Medicine (LKCMedicine)
- Subjects
Gene isoform ,Sequence analysis ,Molecular Sequence Data ,Trans-splicing ,Gene Expression ,Computational biology ,Biology ,Trans-Splicing ,Conserved sequence ,Evolution, Molecular ,Mice ,Circular RNA ,Cell Line, Tumor ,microRNA ,Animals ,Humans ,Ribosome profiling ,Gene ,Conserved Sequence ,Phylogeny ,Genetics ,Base Sequence ,Sequence Analysis, RNA ,Research ,Computational Biology ,RNA, Circular ,Porifera ,MicroRNAs ,Medicine ,RNA - Abstract
Background: The recent reports of two circular RNAs (circRNAs) with strong potential to act as microRNA (miRNA) sponges suggest that circRNAs might play important roles in regulating gene expression. However, the global properties of circRNAs are not well understood. Results: We developed a computational pipeline to identify circRNAs and quantify their relative abundance from RNA-seq data. Applying this pipeline to a large set of non-poly(A)-selected RNA-seq data from the ENCODE project, we annotated 7,112 human circRNAs that were estimated to comprise at least 10% of the transcripts accumulating from their loci. Most circRNAs are expressed in only a few cell types and at low abundance, but they are no more cell-type-specific than are mRNAs with similar overall expression levels. Although most circRNAs overlap protein-coding sequences, ribosome profiling provides no evidence for their translation. We also annotated 635 mouse circRNAs, and although 20% of them are orthologous to human circRNAs, the sequence conservation of these circRNA orthologs is no higher than that of their neighboring linear exons. The previously proposed miR-7 sponge, CDR1as, is one of only two circRNAs with more miRNA sites than expected by chance, with the next best miRNA-sponge candidate deriving from a gene encoding a primate-specific zinc-finger protein, ZNF91. Conclusions: Our results provide a new framework for future investigation of this intriguing topological isoform while raising doubts regarding a biological function of most circRNAs., National Institutes of Health (U.S.) (Grant GM067031), National Science Foundation (U.S.). Graduate Research Fellowship, Damon Runyon Cancer Research Foundation (DRG-2152-13)
- Published
- 2014
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