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Pollution source identification methods and remediation technologies of groundwater: A review
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作者 Ya-ci Liu Yu-hong Fei +2 位作者 Ya-song Li Xi-lin Bao Peng-wei Zhang 《China Geology》 CAS CSCD 2024年第1期125-137,共13页
Groundwater is an important source of drinking water.Groundwater pollution severely endangers drinking water safety and sustainable social development.In the case of groundwater pollution,the top priority is to identi... Groundwater is an important source of drinking water.Groundwater pollution severely endangers drinking water safety and sustainable social development.In the case of groundwater pollution,the top priority is to identify pollution sources,and accurate information on pollution sources is the premise of efficient remediation.Then,an appropriate pollution remediation scheme should be developed according to information on pollution sources,site conditions,and economic costs.The methods for identifying pollution sources mainly include geophysical exploration,geochemistry,isotopic tracing,and numerical modeling.Among these identification methods,only the numerical modeling can recognize various information on pollution sources,while other methods can only identify a certain aspect of pollution sources.The remediation technologies of groundwater can be divided into in-situ and ex-situ remediation technologies according to the remediation location.The in-situ remediation technologies enjoy low costs and a wide remediation range,but their remediation performance is prone to be affected by environmental conditions and cause secondary pollution.The ex-situ remediation technologies boast high remediation efficiency,high processing capacity,and high treatment concentration but suffer high costs.Different methods for pollution source identification and remediation technologies are applicable to different conditions.To achieve the expected identification and remediation results,it is feasible to combine several methods and technologies according to the actual hydrogeological conditions of contaminated sites and the nature of pollutants.Additionally,detailed knowledge about the hydrogeological conditions and stratigraphic structure of the contaminated site is the basis of all work regardless of the adopted identification methods or remediation technologies. 展开更多
关键词 Groundwater pollution identification of pollution sources Geophysical exploration identification Geochemistry identification Isotopic tracing Numerical modeling Remediation technology Hydrogeological conditions Hydrogeological survey engineering
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Application of Next Generation Sequencing for Rapid Identification of Lactic Acid Bacteria
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作者 Xiaxia HOU Yunxia WANG +2 位作者 Shuhuan ZHAO Hongbing JIA Cuizhi LI 《Asian Agricultural Research》 2024年第4期27-32,共6页
The rapid identification of lactic acid bacteria,which are essential microorganisms in the food industry,is of great significance for industrial applications.The identification of lactic acid bacteria traditionally re... The rapid identification of lactic acid bacteria,which are essential microorganisms in the food industry,is of great significance for industrial applications.The identification of lactic acid bacteria traditionally relies on the isolation and identification of pure colonies.While this method is well-established and widely used,it is not without limitations.The subjective judgment inherent in the isolation and purification process introduces potential for error,and the incomplete nature of the isolation process can result in the loss of valuable information.The advent of next generation sequencing has provided a novel approach to the rapid identification of lactic acid bacteria.This technology offers several advantages,including rapidity,accuracy,high throughput,and low cost.Next generation sequencing represents a significant advancement in the field of DNA sequencing.Its ability to rapidly and accurately identify lactic acid bacteria strains in samples with insufficient information or in the presence of multiple lactic acid bacteria sets it apart as a valuable tool.The application of this technology not only circumvents the potential errors inherent in the traditional method but also provides a robust foundation for the expeditious identification of lactic acid bacteria strains and the authentication of bacterial powder in industrial applications.This paper commences with an overview of traditional and molecular biology methods for the identification of lactic acid bacteria.While each method has its own advantages,they are not without limitations in practical application.Subsequently,the paper provides an introduction of the principle,process,advantages,and disadvantages of next generation sequencing,and also details its application in strain identification and rapid identification of lactic acid bacteria.The objective of this study is to provide a comprehensive and reliable basis for the rapid identification of industrial lactic acid bacteria strains and the authenticity identification of bacterial powder. 展开更多
关键词 LACTIC ACID BACTERIA RAPID identification NEXT generation SEQUENCING
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Simultaneous Waveform Inverse Modelling for Litho-Fluid Prediction in an Old Marginal, “Agbbo”Field, Onshore Niger Delta, Nigeria
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作者 Charles Chibueze Ugbor Peter Ogobi Odong Chukwuemeka Austine Okonkwo 《Journal of Geoscience and Environment Protection》 2024年第5期40-59,共20页
Simultaneous waveform inversion was used to predict lithofacies and fluid type across the field. Very often, characterizing reservoirs in terms of lithology and fluid type using conventional methods is replete with un... Simultaneous waveform inversion was used to predict lithofacies and fluid type across the field. Very often, characterizing reservoirs in terms of lithology and fluid type using conventional methods is replete with uncertainties, especially in marginal fields. An approach is employed in this study that integrated rock physics and waveform inverse modelling for lithology and fluid-type characterization to appropriately identify potential hydrocarbon saturated zones and their corresponding lithology. Seismic and well-log data were analyzed using Hampson Russel software. The method adopted includes lithofacies and fluid content analysis using rock physics parameters and seismic simultaneous inverse modelling. Rock physics analysis identified 2 broad reservoirs namely: HDZ1 and HDZ2 reservoirs. Results from the inverse modelling showed that low values of acoustic impedance from 19,743 to 20,487 (ft/s)(g/cc) reflect hydrocarbon-bearing reservoirs while medium to high values shows brine and shale respectively, with brine zone ranging from 20,487 to 22,531 (ft/s)(g/cc) and shale above 22,531 (ft/s)(g/cc). Two lithofacies were identified from inversion analysis of Vp/Vs and Mu-Rho, namely: sand and shale with VpVs 1.95 values respectively. Mu-Rho > 12.29 (GPa)(g/cc) and <12.29 (GPa) (g/cc) represent sand and shale respectively. From 3D volume, it was observed that a high accumulation of hydrocarbon was observed to be saturated at the north to the eastern part of the field forming a meandering channel. Sands were mainly distributed around the northeastern to the southwestern part of the field, that tends to be away from Well 029. This was also validated by the volume of rigidity modulus (Mu-Rho) showing high values indicating sands fall within the northeastern part of the field. 展开更多
关键词 Simultaneous waveform Inversion Lithofacies Fluid Type Rock Physics HYDROCARBON Acoustic Impedance Mu-Rho Reservoir
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Identification and evaluation of shale oil micromigration and its petroleum geological significance
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作者 HU Tao JIANG Fujie +10 位作者 PANG Xiongqi LIU Yuan WU Guanyun ZHOU Kuo XIAO Huiyi JIANG Zhenxue LI Maowen JIANG Shu HUANG Liliang CHEN Dongxia MENG Qingyang 《Petroleum Exploration and Development》 SCIE 2024年第1期127-140,共14页
Taking the Lower Permian Fengcheng Formation shale in Mahu Sag of Junggar Basin,NW China,as an example,core observation,test analysis,geological analysis and numerical simulation were applied to identify the shale oil... Taking the Lower Permian Fengcheng Formation shale in Mahu Sag of Junggar Basin,NW China,as an example,core observation,test analysis,geological analysis and numerical simulation were applied to identify the shale oil micro-migration phenomenon.The hydrocarbon micro-migration in shale oil was quantitatively evaluated and verified by a self-created hydrocarbon expulsion potential method,and the petroleum geological significance of shale oil micro-migration evaluation was determined.Results show that significant micro-migration can be recognized between the organic-rich lamina and organic-poor lamina.The organic-rich lamina has strong hydrocarbon generation ability.The heavy components of hydrocarbon preferentially retained by kerogen swelling or adsorption,while the light components of hydrocarbon were migrated and accumulated to the interbedded felsic or carbonate organic-poor laminae as free oil.About 69% of the Fengcheng Formation shale samples in Well MY1 exhibit hydrocarbon charging phenomenon,while 31% of those exhibit hydrocarbon expulsion phenomenon.The reliability of the micro-migration evaluation results was verified by combining the group components based on the geochromatography effect,two-dimension nuclear magnetic resonance analysis,and the geochemical behavior of inorganic manganese elements in the process of hydrocarbon migration.Micro-migration is a bridge connecting the hydrocarbon accumulation elements in shale formations,which reflects the whole process of shale oil generation,expulsion and accumulation,and controls the content and composition of shale oil.The identification and evaluation of shale oil micro-migration will provide new perspectives for dynamically differential enrichment mechanism of shale oil and establishing a“multi-peak model in oil generation”of shale. 展开更多
关键词 shale oil micro-migration identification micro-migration evaluation Junggar Basin Mahu Sag Lower Permian Fengcheng Formation hydrocarbon expulsion potential method
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Link Budget Design with Performance Evaluation of Tunable Impulse-Based Ultra Wideband to Support the Integration of Wireless Sensing and Identifications Infrastructures
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作者 Mohammed Seed Jawad Widad Ismail +2 位作者 Ayman Hajjawi Othman Abdul Rani Azahari Saleh 《Journal of Sensor Technology》 2014年第3期127-138,共12页
Recently, many studies propose the use of ultra-wideband technology for passive and active radio frequency identification systems as well as for wireless sensor networks due to its numerous advantages. By harvesting t... Recently, many studies propose the use of ultra-wideband technology for passive and active radio frequency identification systems as well as for wireless sensor networks due to its numerous advantages. By harvesting these advantages of IR-UWB technology at the physical-layer design, this paper proposes that a cross layer architecture platform can be considered as a good integrator for different wireless short-ranges indoor protocols into a universal smart wireless-tagged architecture with new promising applications in cognitive radio for future applications. Adaptive transmission algorithms have been studied to show the trade-off between different specific QoS requirements, transmission rates and distances at the physical layer level and this type of dynamic optimization and reconfiguration leads to the cross-layer design proposal in the paper. Studies from both theoretical simulation and statistical indoor environments experiments are considered as a proof of concept for the proposed architecture. 展开更多
关键词 RADIO Frequency identification (RFID) ULTRA-WIDEBAND (UWB) Impulse-Based ULTRA-WIDEBAND (IR-UWB) Cognitive RADIO (CR) Time Hopping Pulse Position Modulation (TH-PPM) Quality of Service (QoS)
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Identification and Control of Typical Industrial Process 被引量:1
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作者 PENG Hui WU Shao-cheng 《Journal of Central South University》 SCIE EI CAS 2000年第3期165-169,共5页
Many industrial processes such as heating furnaces have over damping dynamic characteristics. Based on an innovative impulse response model, a method of identification and control for the over damping plant is introdu... Many industrial processes such as heating furnaces have over damping dynamic characteristics. Based on an innovative impulse response model, a method of identification and control for the over damping plant is introduced in the paper. The number of parameters of the model is much less than conventional impulse response model. The model based on tuning procedure of numerical optimum PID controller parameters is presented. For an actual instance, a large scale airflow circulatory resistance furnace control system with cascades of time delays is developed. In the system, the optimum PID control is used in the inner loop. A nonlinear PI compensation control is applied in the outer loop. The coordinating control among each output is realized by a fuzzy control strategy. A process surveillance organization monitors running situation of system and tunes controller parameters. 展开更多
关键词 over DAMPING dynamics time delay CASCADE plant IMPULSE response sequence identification optimal PID parameters numerical PID CONTROLLER coordinating control
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Establishment of a molecular tool for blood meal identification in Malaysia 被引量:1
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作者 Ernieenor Faraliana Che Lah Mariana Ahamad +1 位作者 Mohd Subail Haron Ho Tze Ming 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第3期223-227,共5页
Objective:To establish a polymerase chain reaction(PCR) technique based on cytochrome b {cytb) gene of mitochondria DNA(mtDNA) for blood meal identification.Methods:The PCR technique was established based on published... Objective:To establish a polymerase chain reaction(PCR) technique based on cytochrome b {cytb) gene of mitochondria DNA(mtDNA) for blood meal identification.Methods:The PCR technique was established based on published information and validated using blood sample of laboratory animals of which their whole gene sequences are available in CenBank.PCR was next performed to compile gene sequences of different species of wild rodents.The primers used were complementary to the conserved region of the cytb gene of vertebrate's mtDNA.A total of 100 blood samples,both from laboratory animals and wild rodents were collected und analyzed.The obtained unknown sequences were compared with those in the GenBank database using BLAST program to identify the vertebrate animal species.Results:Gene sequences of 11 species of wild animals caught in 9 localities of Peninsular Malaysia were compiled using the established PCR. The animals involved were Rattus(rattus) tanezumi,Rattus tiomanicus,Leopoldamys sabanus, Tupaia glis,Tupaia minor,Niviventor cremoriventor,Rhinosciurus laticaudatus,Calloseiurus caniseps,Sundamys muelleri,Rattus rajah,and Maxomys whitelwadi.The BLAST results confirmed the host with exact or nearly exact matches(>89%identity).Ten new gene sequences have been deposited in CenBank database since September 2010.Conclusions:This study indicates that the PCR direct sequencing system using universal primer sets for vertebrate cytb gene is a promising technique for blood meal identification. 展开更多
关键词 MOLECULAR TOOL BLOOD MEAL identification Polymerase chain reaction Cytochrome b BLOOD MEAL Mitochondria DNA Gene sequence VERTEBRATE Primer GenBank database
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泰山赤鳞鱼同工酶性别和组织表型差异的研究(英文) 被引量:6
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作者 庞秋香 庞书香 +5 位作者 赵博生 宿烽 孙欢欢 颜越 吕志林 刘龙 《Agricultural Science & Technology》 CAS 2010年第5期101-105,共5页
应用聚丙烯酰胺凝胶电泳结合生化染色方法分别对雌雄泰山赤鳞鱼11种组织中苹果酸脱氢酶(Malate dehydrogenase,MDH,E.C.1.1.1.37)同工酶酶谱进行了分析。首次发现苹果酸脱氢酶、酸性磷酸酶和超氧化物岐化酶表型在赤鳞鱼雌性和雄性之间... 应用聚丙烯酰胺凝胶电泳结合生化染色方法分别对雌雄泰山赤鳞鱼11种组织中苹果酸脱氢酶(Malate dehydrogenase,MDH,E.C.1.1.1.37)同工酶酶谱进行了分析。首次发现苹果酸脱氢酶、酸性磷酸酶和超氧化物岐化酶表型在赤鳞鱼雌性和雄性之间存在差异,而在同一性别不同个体之间无差异。因此,苹果酸脱氢酶、酸性磷酸酶和超氧化物岐化酶的电泳酶谱可以作为一项指标用于泰山赤鳞鱼性别和组织的鉴定。这将为赤磷鱼种群的发育遗传学、品种改良和定向育种提供基础资料,从而有利于这一名贵育鱼种的开发和保护。 展开更多
关键词 ISOZYME Differences MALATE dehydrogenase superoxide DISMUTASE development and protection developmental genetics difference gel electrophoresis different identification of staining method
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CRUST AND UPPER STRUCTURE OF QINGHAI-TIBET PLATEAU AND ITS ADJACENT REGIONS FROM SURFACE WAVEFORM INVERSION
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作者 Cao Xiaolin,Cao Jamin,Zhu Jieshou 《地学前缘》 EI CAS CSCD 2000年第S1期316-316,共1页
In this paper,218 long period Rayleigh wave records from 7 seismic station of CDSN are selected.We applied a partitioned waveform inversion to these data in order to construct a 3\|D model of shear velocity down to 40... In this paper,218 long period Rayleigh wave records from 7 seismic station of CDSN are selected.We applied a partitioned waveform inversion to these data in order to construct a 3\|D model of shear velocity down to 400km depth in the crust and upper mantle of Qinghai\|Tibet plateau and Its Adjacent Regions (22°~44°N,70°~110°E).The first step of the waveform inversion used involved the matching of the waveforms of fundamental and highermost Ravleigh waves with waveforms synthesized from stratified models;in the second stage,the 3\|D model was constructed by solve linear constrains equation. The major structural features inferred from the surface waveform inversions can be summarized as follows:(1) There is a great contrast between surface waveform through Qinghai—Thibet plateau and the others.Main frequency of the former is lower than the latter, which indicate the crust depth of Qinghai—Tibet plateau is deeper than the others. In addition,the amplitude of about 30s period and 50s period is lower than both sides,which implied these exist lower velocity layer at about 25km depth and about 50km depth in Qinghai—Tibet plateau Crust.The former is common,the latter was argued because resolution of most method can not prove it. 展开更多
关键词 QinghaiTibet plateau long period Rayleigh wave partitioned waveform inversion 3\|D model of shear VELOCITY lower VELOCITY layer LITHOSPHERE STRUCTURE
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Automatic Identification for Laparoscopic Surgical Procedure for Ligation and Online Distinction of Abnormal Manipulation for Thread Knotting
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作者 Chiharu Ishii Takanori Sato +1 位作者 Kaito Murano Hideki Kawamura 《International Journal of Clinical Medicine》 2015年第12期887-898,共12页
Laparoscopic surgery is a difficult surgical procedure compared with laparotomy. In particular, considerable skills and care are required for thread knotting in laparoscopic surgery. In this paper, a method for automa... Laparoscopic surgery is a difficult surgical procedure compared with laparotomy. In particular, considerable skills and care are required for thread knotting in laparoscopic surgery. In this paper, a method for automatic identification of a laparoscopic surgical procedure for ligation and online distinction of an abnormality, defined as any unusual manipulation, in the identified surgical procedure is proposed. Ligation is divided into several individual surgical procedures, and on the basis of the threshold criteria, each surgical procedure is identified. Next, the identified surgical procedure, thread knotting, is classified as either normal or abnormal using a self-organizing map. Finally, to reduce surgical error, an abnormality warning system which warns detection of an unusual manipulation in the surgical procedure to the operator is constructed. 展开更多
关键词 Automatic identification of SURGICAL PROCEDURE DISTINCTION of ABNORMAL MANIPULATION in SURGICAL PROCEDURE Abnormality Warning System Surface Electromyogram (SEMG) Self-Organizing Map (SOM)
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致麻鸭产蛋下降的副粘病毒的分离和鉴定 被引量:36
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作者 何永强 洪健 +2 位作者 吴旧生 杜青云 倪征 《中国兽医学报》 CAS CSCD 北大核心 2005年第3期238-241,共4页
从浙江省某麻鸭养殖基地产蛋锐减的病鸭生殖器官分离到1株致产蛋下降、不致鸭死亡的病毒株(YH99V)。该病毒易感蛋鸭,经SPF鸡胚传至第9代时致病性突然增强,第11代出现对鸡红细胞的血凝特性,通常在42~80h致死SPF鸡胚,EF15EID50为10-4.8... 从浙江省某麻鸭养殖基地产蛋锐减的病鸭生殖器官分离到1株致产蛋下降、不致鸭死亡的病毒株(YH99V)。该病毒易感蛋鸭,经SPF鸡胚传至第9代时致病性突然增强,第11代出现对鸡红细胞的血凝特性,通常在42~80h致死SPF鸡胚,EF15EID50为10-4.8。经磷钨酸负染电镜观察,YH99V粒子呈现圆形、杆状形、葫芦状形等多形态,直径70~400nm不等,病毒外表有囊膜,囊膜外层有排列整齐的纤突。病毒粒子和包涵体位于细胞浆内。病毒抵抗力由弱到强依次为0.2%甲醛、24h→56℃、45min→紫外线、1h→乙醚≈氯仿≈37℃、16h→pH9→pH5→1%Try。对人眼结膜易感,鸭眼结膜不易感。接种传代细胞BHK-21、IBRS-2均能引起细胞病变。YH99V株与同样引起鸭产蛋下降的AIV、鸭源EDSV无抗原相关性,而能被禽副粘病毒型阳性血清中和。根据试验结果,初步将YH99V判定为鸭副粘病毒。 展开更多
关键词 SPF EDSV 线 AIV
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Recovery of saturated signal waveform acquired from high-energy particles with artificial neural networks 被引量:4
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作者 Yu Liu Jing-Jun Zhu +5 位作者 Neil Roberts Ke-Ming Chen Yu-Lu Yan Shuang-Rong Mo Peng Gu Hao-Yang Xing 《Nuclear Science and Techniques》 SCIE CAS CSCD 2019年第10期30-39,共10页
Artificial neural networks(ANNs)are a core component of artificial intelligence and are frequently used in machine learning.In this report,we investigate the use of ANNs to recover the saturated signals acquired in hi... Artificial neural networks(ANNs)are a core component of artificial intelligence and are frequently used in machine learning.In this report,we investigate the use of ANNs to recover the saturated signals acquired in highenergy particle and nuclear physics experiments.The inherent properties of the detector and hardware imply that particles with relatively high energies probably often generate saturated signals.Usually,these saturated signals are discarded during data processing,and therefore,some useful information is lost.Thus,it is worth restoring the saturated signals to their normal form.The mapping from a saturated signal waveform to a normal signal waveform constitutes a regression problem.Given that the scintillator and collection usually do not form a linear system,typical regression methods such as multi-parameter fitting are not immediately applicable.One important advantage of ANNs is their capability to process nonlinear regression problems.To recover the saturated signal,three typical ANNs were tested including backpropagation(BP),simple recurrent(Elman),and generalized radial basis function(GRBF)neural networks(NNs).They represent a basic network structure,a network structure with feedback,and a network structure with a kernel function,respectively.The saturated waveforms were produced mainly by the environmental gamma in a liquid scintillation detector for the China Dark Matter Detection Experiment(CDEX).The training and test data sets consisted of 6000 and 3000 recordings of background radiation,respectively,in which saturation was simulated by truncating each waveform at 40%of the maximum signal.The results show that the GBRF-NN performed best as measured using a Chi-squared test to compare the original and reconstructed signals in the region in which saturation was simulated.A comparison of the original and reconstructed signals in this region shows that the GBRF neural network produced the best performance.This ANN demonstrates a powerful efficacy in terms of solving the saturation recovery problem.The proposed method outlines new ideas and possibilities for the recovery of saturated signals in high-energy particle and nuclear physics experiments.This study also illustrates an innovative application of machine learning in the analysis of experimental data in particle physics. 展开更多
关键词 Saturated signals Artificial NEURAL networks(ANNs) RECOVERY of signal waveform Generalized radial basis function Backpropagation NEURAL NETWORK ELMAN NEURAL NETWORK
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Isolation, Identification and Pathogenicity Analysis of Streptococcus suis Type 2 被引量:4
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作者 Zicheng MA Yan LI +6 位作者 Jinyuan GU Tao PENG Zhaohu LIU Hongyu WANG Fanliang MENG Fangkun WANG Sidang LIU 《Agricultural Biotechnology》 CAS 2019年第4期64-68,共5页
[Objectives]This study aimed to investigate the pathogenicity,growth characteristics and drug resistance of Streptococcus suis type 2.[Methods]Bacterial isolation and identification,biochemical experiments,determinati... [Objectives]This study aimed to investigate the pathogenicity,growth characteristics and drug resistance of Streptococcus suis type 2.[Methods]Bacterial isolation and identification,biochemical experiments,determination of growth curve and correlation curve between OD 600 values and viable counts,drug susceptibility tests,pathogenicity analysis,and histopathological observations were carried out.[Results]The Streptococcus strain isolated from infected pigs was identified as Streptococcus suis type 2,which was named TA01 strain.TA01 strain reached the growth peak at 6-8 h post-incubation,and viable counts gradually declined after 8 h of incubation.The correlation equation between OD 600 values and viable counts is y=24.659 x-1.076 1,R^2=0.996 7.TA01 strain was sensitive to penicillin,erythromycin,florfenicol and oxacillin,and resistant to ciprofloxacin,polymyxin B and clindamycin.According to the results of pathogenicity analysis,all the mice in 3.6×10^9 cfu/mouse group died within 48,and these dead mice exhibited acute pyaemia septica.Based on the Reed-Muench formula,it was calculated that LD 50 of TA01 strain was 1.137×10^8 cfu/mouse.Pathological examination showed obvious blue-stained bacteria clusters,accompanied by neutrophil infiltration.[Conclusions]TA01 strain was a virulent strain of Streptococcus suis type 2.Compared with Streptococcus strains which were isolated and reported in China,TA01 strain exhibited strong virulence and rapid proliferation. 展开更多
关键词 STREPTOCOCCUS SUIS TYPE 2 ISOLATION and identification Growth curve Drug sensitivity test PATHOGENICITY LD 50 determination
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Joint Design of ISAC Waveform Under PAPR Constraints
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作者 Chen Yating Wen Cai +4 位作者 Huang Yan Liang Le Li Jie Zhang Hui HongWei 《China Communications》 SCIE CSCD 2024年第7期186-211,共26页
In this paper,we formulate the precoding problem of integrated sensing and communication(ISAC)waveform as a non-convex quadratically constrained quadratic programming(QCQP),in which the weighted sum of communication m... In this paper,we formulate the precoding problem of integrated sensing and communication(ISAC)waveform as a non-convex quadratically constrained quadratic programming(QCQP),in which the weighted sum of communication multi-user interference(MUI)and the gap between dual-use waveform and ideal radar waveform is minimized with peak-toaverage power ratio(PAPR)constraints.We propose an efficient algorithm based on alternating direction method of multipliers(ADMM),which is able to decouple multiple variables and provide a closed-form solution for each subproblem.In addition,to improve the sensing performance in both spatial and temporal domains,we propose a new criteria to design the ideal radar waveform,in which the beam pattern is made similar to the ideal one and the integrated sidelobe level of the ambiguity function in each target direction is minimized in the region of interest.The limited memory Broyden-Fletcher-Goldfarb-Shanno(LBFGS)algorithm is applied to the design of the ideal radar waveform which works as a reference in the design of the dual-function waveform.Numerical results indicate that the designed dual-function waveform is capable of offering good communication quality of service(QoS)and sensing performance. 展开更多
关键词 ambiguity function integrated sensing and communication MIMO OFDM PAPR waveform design
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温州地区鸭疫里默氏杆菌的分离、鉴定及药敏试验 被引量:9
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作者 王连胜 李龙 +2 位作者 林日春 项延润 于涟 《浙江农业学报》 CSCD 2005年第2期98-100,共3页
从浙江省温州地区2004年鸭场送检病死鸭的脑、心包液、脾及肝中分离到WZ1和WZ2两株细菌,将这两株细菌进行菌落形态观察、染色镜检、生化、血清鉴定及动物回归试验,证实该两株菌为鸭疫里默氏杆菌。两株细菌均对新霉素、头孢孟多、氟嗪酸... 从浙江省温州地区2004年鸭场送检病死鸭的脑、心包液、脾及肝中分离到WZ1和WZ2两株细菌,将这两株细菌进行菌落形态观察、染色镜检、生化、血清鉴定及动物回归试验,证实该两株菌为鸭疫里默氏杆菌。两株细菌均对新霉素、头孢孟多、氟嗪酸及壮观霉素等抗生素敏感,对氟哌酸、氨卡青霉素、链霉素、庆大霉素、环丙沙星、氯霉素等不敏感。血清学试验表明,WZ1和WZ2两待检菌株血清型一致,但均不属于1型和2型。 展开更多
关键词 2004
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Hyperspectral remote sensing identification of marine oil emulsions based on the fusion of spatial and spectral features
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作者 Xinyue Huang Yi Ma +1 位作者 Zongchen Jiang Junfang Yang 《Acta Oceanologica Sinica》 SCIE CAS CSCD 2024年第3期139-154,共16页
Marine oil spill emulsions are difficult to recover,and the damage to the environment is not easy to eliminate.The use of remote sensing to accurately identify oil spill emulsions is highly important for the protectio... Marine oil spill emulsions are difficult to recover,and the damage to the environment is not easy to eliminate.The use of remote sensing to accurately identify oil spill emulsions is highly important for the protection of marine environments.However,the spectrum of oil emulsions changes due to different water content.Hyperspectral remote sensing and deep learning can use spectral and spatial information to identify different types of oil emulsions.Nonetheless,hyperspectral data can also cause information redundancy,reducing classification accuracy and efficiency,and even overfitting in machine learning models.To address these problems,an oil emulsion deep-learning identification model with spatial-spectral feature fusion is established,and feature bands that can distinguish between crude oil,seawater,water-in-oil emulsion(WO),and oil-in-water emulsion(OW)are filtered based on a standard deviation threshold–mutual information method.Using oil spill airborne hyperspectral data,we conducted identification experiments on oil emulsions in different background waters and under different spatial and temporal conditions,analyzed the transferability of the model,and explored the effects of feature band selection and spectral resolution on the identification of oil emulsions.The results show the following.(1)The standard deviation–mutual information feature selection method is able to effectively extract feature bands that can distinguish between WO,OW,oil slick,and seawater.The number of bands was reduced from 224 to 134 after feature selection on the Airborne Visible Infrared Imaging Spectrometer(AVIRIS)data and from 126 to 100 on the S185 data.(2)With feature selection,the overall accuracy and Kappa of the identification results for the training area are 91.80%and 0.86,respectively,improved by 2.62%and 0.04,and the overall accuracy and Kappa of the identification results for the migration area are 86.53%and 0.80,respectively,improved by 3.45%and 0.05.(3)The oil emulsion identification model has a certain degree of transferability and can effectively identify oil spill emulsions for AVIRIS data at different times and locations,with an overall accuracy of more than 80%,Kappa coefficient of more than 0.7,and F1 score of 0.75 or more for each category.(4)As the spectral resolution decreasing,the model yields different degrees of misclassification for areas with a mixed distribution of oil slick and seawater or mixed distribution of WO and OW.Based on the above experimental results,we demonstrate that the oil emulsion identification model with spatial–spectral feature fusion achieves a high accuracy rate in identifying oil emulsion using airborne hyperspectral data,and can be applied to images under different spatial and temporal conditions.Furthermore,we also elucidate the impact of factors such as spectral resolution and background water bodies on the identification process.These findings provide new reference for future endeavors in automated marine oil spill detection. 展开更多
关键词 oil emulsions identification hyperspectral remote sensing feature selection convolutional neural network(CNN) spatial-temporal transferability
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流变荷载试验曲线的模型识别及其应用 被引量:19
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作者 李云鹏 王芝银 丁秀丽 《石油大学学报(自然科学版)》 EI CSCD 北大核心 2005年第2期73-77,共5页
基于粘弹性理论,建立了流变荷载试验的Maxwell、广义Kelvin和Burgers3种流变模型的位移反演模式,并给出了根据现场试验流变曲线进行流变模型识别的简便方法。分析了岩体流变荷载试验曲线,给出了能反映试验区域内岩体变形规律的最佳流变... 基于粘弹性理论,建立了流变荷载试验的Maxwell、广义Kelvin和Burgers3种流变模型的位移反演模式,并给出了根据现场试验流变曲线进行流变模型识别的简便方法。分析了岩体流变荷载试验曲线,给出了能反映试验区域内岩体变形规律的最佳流变模型,反演获得了试验区域内岩体的瞬时弹性模量、长期弹性模量、粘弹性模量和粘弹性系数。结果表明,描述试验点岩体在不同荷载级别情况下的最佳流变模型均为广义Kelvin模型,但其弹性模量有所差异,其量值范围为4194~5235MPa,平均弹性模量为4900.316MPa;平均长期弹性模量为3081.65MPa。计算表明所建立的反演公式是正确的,模型及参数识别过程简便、实用。 展开更多
关键词 线 KELVIN Maxwell 便 线 4900 广
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一种新的预测冰蓄冷空调负荷的ARMAX模型辨识方法
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作者 徐今强 冯自平 Jin-qiang Zi-ping 《计量学报》 CSCD 北大核心 2009年第6期-,共4页
基于系统辨识理论,提出一种新的预测冰蓄冷中央空调平均负荷的外源自回归滑动平均(ARMAX)模型辨识方法.首先根据空调负荷历史数据构建次日平均负荷的ARMAX模型;然后基于不同的室外最高温度建立自适应ARMAX温度区间模型,该模型由几组参... 基于系统辨识理论,提出一种新的预测冰蓄冷中央空调平均负荷的外源自回归滑动平均(ARMAX)模型辨识方法.首先根据空调负荷历史数据构建次日平均负荷的ARMAX模型;然后基于不同的室外最高温度建立自适应ARMAX温度区间模型,该模型由几组参数时变的子模型组成,子模型参数由在线回归算法辨识.测试数据表明,所提出的ARMAX温度区间模型与传统的ARMAX模型相比具有较高的预测精度,而且室外最高温度差异越大,效果越明显,可用于冰蓄冷中央空调的优化控制. Abstract: A novel ARMAX model identification method for average load forecasting of ice-storage central air conditioning is introduced based on system identification theory. Firstly an ARMAX model for the next day average load is obtained according to the historical data,then an adaptive ARMAX model is proposed based on different outdoor maximum temperature, the temperature interval based ARMAX model is composed of several time-varyiag sub-models whose parameters are identified using an on-line regression algorithm. As a result, the proposed model has good quality in terms of prediction precision in comparison with traditional ARMAX model, besides, the more outdoor maximum temperature difference, the better prediction precision, it can be applied to the optimal control of ice-storage central air conditioning. 展开更多
关键词 ARMAX AIR CONDITIONING LOAD Forecasting identification Method ARMAX Model ARMAX model AIR CONDITIONING temperature difference system identification identification method LOAD forecasting optimal control based
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Two-Staged Method for Ice Channel Identification Based on Image Segmentation and Corner Point Regression 被引量:1
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作者 DONG Wen-bo ZHOU Li +2 位作者 DING Shi-feng WANG Ai-ming CAI Jin-yan 《China Ocean Engineering》 SCIE EI CSCD 2024年第2期313-325,共13页
Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of navigation.In the Arctic,merchant ships with low ... Identification of the ice channel is the basic technology for developing intelligent ships in ice-covered waters,which is important to ensure the safety and economy of navigation.In the Arctic,merchant ships with low ice class often navigate in channels opened up by icebreakers.Navigation in the ice channel often depends on good maneuverability skills and abundant experience from the captain to a large extent.The ship may get stuck if steered into ice fields off the channel.Under this circumstance,it is very important to study how to identify the boundary lines of ice channels with a reliable method.In this paper,a two-staged ice channel identification method is developed based on image segmentation and corner point regression.The first stage employs the image segmentation method to extract channel regions.In the second stage,an intelligent corner regression network is proposed to extract the channel boundary lines from the channel region.A non-intelligent angle-based filtering and clustering method is proposed and compared with corner point regression network.The training and evaluation of the segmentation method and corner regression network are carried out on the synthetic and real ice channel dataset.The evaluation results show that the accuracy of the method using the corner point regression network in the second stage is achieved as high as 73.33%on the synthetic ice channel dataset and 70.66%on the real ice channel dataset,and the processing speed can reach up to 14.58frames per second. 展开更多
关键词 ice channel ship navigation identification image segmentation corner point regression
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Genetic Diversity and Species Identification of Cultivar Species in Subtribe Cucumerinae (Cucurbitaceae) Using RAPD and SCAR Markers 被引量:4
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作者 Juthaporn Saengprajak Piyaporn Saensouk 《American Journal of Plant Sciences》 2012年第8期1092-1097,共6页
DNA polymorphism in the cultivar species;Cucumis sativus L., C. melo L. and Benincasa hispida Cogn. of subtribe Cucumerinae (Cucurbitaceae) in the four northeastern provinces of Thailand was examined by using RAPD tec... DNA polymorphism in the cultivar species;Cucumis sativus L., C. melo L. and Benincasa hispida Cogn. of subtribe Cucumerinae (Cucurbitaceae) in the four northeastern provinces of Thailand was examined by using RAPD technique. Twenty 10-mer primers were produced 212 RAPD fragments, ranging from approximately 120 to 2531 bp. The genetic similarities were estimated from banding profiles using a NTSYS* version 2.1 as a basis for dendrogram construction via the UPGMA method. Cluster analysis divided the taxa under study into 2 clades. Moreover, a RAPD marker: Cm (OPJ11700) was specified to C. melo, and this marker was converted into sequence characterized amplified region (SCAR) marker: Cm (SCJ11516). A pair of sequence-specific primer of clones Cm (OPJ11700) amplified a distinct single band of the same size as the RAPD clones. The SCAR marker was developed successfully to identify C. melo genotype. 展开更多
关键词 Cucumerinae CUCURBITACEAE Genetic Diversity Random Amplified POLYMORPHIC DNA (RAPD) Sequence Characterized Amplified Region (SCAR) SPECIES identification
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