Real-time tracking of fast-moving object in occlusion scene

Tracking the fast-moving object in occlusion situations is an important research topic in computer vision. Despite numerous notable contributions have been made in this field,few of them simultaneously incorporate both object's extrinsic features and intrinsic motion patterns into their methodologies,thereby restricting the potential for tracking accuracy improvement. In this paper, on the basis of efficient convolution operators(ECO) model, a speed-accuracy-balanced model is put forward. This model uses the simple correlation filter to track the object in real-time, and adopts the sophisticated deep-learning neural network to extract high-level features to train a more complex filter correcting the tracking mistakes, when the tracking state is judged to be poor. Furthermore, in the context of scenarios involving regular fast-moving, a motion model based on Kalman filter is designed which greatly promotes the tracking stability, because this motion model could predict the object's future location from its previous movement pattern. Additionally,instead of periodically updating our tracking model and training samples, a constrained condition for updating is proposed,which effectively mitigates contamination to the tracker from the background and undesirable samples avoiding model degradation when occlusion happens. From comprehensive experiments, our tracking model obtains better performance than ECO on object tracking benchmark 2015(OTB100), and improves the area under curve(AUC) by about 8% and 32% compared with ECO, in the scenarios of fast-moving and occlusion on our own collected dataset.

Separate-layer balanced waterflooding development technology for thick and complex carbonate reservoirs in the Middle East

Based on the waterflooding development in carbonate reservoirs in the Middle East,in order to solve the problem of the poor development effects caused by commingled injection and production,taking the thick bioclastic limestone reservoirs of Cretaceous in Iran-Iraq as an example,this paper proposes a balanced waterflooding development technology for thick and complex carbonate reservoirs.This technology includes the fine division of development units by concealed baffles and barriers,the combination of multi well type and multi well pattern,and the construction of balanced water injection and recovery system.Thick carbonate reservoirs in Iran-Iraq are characterized by extremely vertical heterogeneity,development of multi-genesis ultra-high permeability zones,and highly concealed baffles and barriers.Based on the technologies of identification,characterization,and sealing evaluation for concealed baffles and barriers,the balanced waterflooding development technology is proposed,and three types of balanced waterflooding development modes/techniques are formed,namely,conventional stratigraphic framework,fine stratigraphic framework,and deepened stratigraphic framework.Numerical simulations show that this technology is able to realize a fine and efficient waterflooding development to recover,in a balanced manner,the reserves of thick and complex carbonate reservoirs in Iran and Iraq.The proposed technology provides a reference for the development optimization of similar reservoirs.

Fast and Balanced Charge Transport Enabled by Solution-Processed Metal Oxide Layers for Efficient and Stable Inverted Perovskite Solar Cells

Metal oxide charge transport materials are preferable for realizing long-term stable and potentially low-cost perovskite solar cells(PSCs).However,due to some technical difficulties(e.g.,intricate fabrication protocols,high-temperature heating process,incompatible solvents,etc.),it is still challenging to achieve efficient and reliable all-metal-oxide-based devices.Here,we developed efficient inverted PSCs(IPSCs)based on solution-processed nickel oxide(NiO_(x))and tin oxide(SnO_(2))nanoparticles,working as hole and electron transport materials respectively,enabling a fast and balanced charge transfer for photogenerated charge carriers.Through further understanding and optimizing the perovskite/metal oxide interfaces,we have realized an outstanding power conversion efficiency(PCE)of 23.5%(the bandgap of the perovskite is 1.62 eV),which is the highest efficiency among IPSCs based on all-metal-oxide charge transport materials.Thanks to these stable metal oxides and improved interface properties,ambient stability(retaining 95%of initial PCE after 1 month),thermal stability(retaining 80%of initial PCE after 2 weeks)and light stability(retaining 90%of initial PCE after 1000 hours aging)of resultant devices are enhanced significantly.In addition,owing to the low-temperature fabrication procedures of the entire device,we have obtained a PCE of over 21%for flexible IPSCs with enhanced operational stability.

Research on the Balanced Development of Urban and Rural Compulsory Education Through Education Resource Allocation

With the rapid development of our country’s economy,education has gradually become the focus of social attention.The problem of unbalanced distribution of urban and rural educational resources has become increasingly prominent,urban educational resources are relatively rich,while rural educational resources are relatively scarce,and the balanced development of urban and rural compulsory education has become an urgent task.This paper mainly investigates and studies the distribution of urban and rural educational resources,discusses the unbalanced distribution of urban and rural educational resources and analyzes the reasons,and puts forward a series of corresponding solutions to promote the balanced development of urban and rural compulsory education.

A Structural Interpretation Model and Restoration of the Mesozoic Proto-basin for the Kuqa Depression,Tarim Basin

A thrust-fold belt consisting of a series of thrusts and buckling folds developed in the Mesozoic and Cenozoic strata within the Kuqa Depression,Tarim Basin.In this study,a structural interpretation model of the Kuqa Depression is established and the Mesozoic proto-basin is reconstructed on the basis of outcrop geology along the basin margin,seismic,well-log and CEMP data.The model is called‘delaminate contractional deformation',which emphasizes the decoupling between the Cenozoic,Mesozoic,pre-Mesozoic and the basin-basement within the Kuqa Depression,but there is no unified detachment.The model has a shortening amount ranging from 12 km to 16 km and the depth involved in contractional deformation ranges from 21 km to 28 km.A prototype of the Mesozoic basin reconstructed by interpretation model is a subbasin superposed on the transitional zone between the uplift at the northern edge of the Tarim Craton and the southern Tianshan orogenic wedge formed in the Hercynian orogeny.Lithospheric thermal and crustal isostatic activity after the Hercynian orogeny maybe the controlling dynamic factors of basin subsidence during the Mesozoic and early Cenozoic,the difference in rock mechanical properties between different levels,craton and orogenic wedge being the major cause of the‘delaminate contractional deformation'during the Himalayan orogeny.

Learning-Based Dynamic Connectivity Maintenance for UAV-Assisted D2D Multicast Communication

Unmanned aerial vehicles(UAVs) enable flexible networking functions in emergency scenarios.However,due to the movement characteristic of ground users(GUs),it is challenging to capture the interactions among GUs.Thus,we propose a learningbased dynamic connectivity maintenance architecture to reduce the delay for the UAV-assisted device-todevice(D2D) multicast communication.In this paper,each UAV transmits information to a selected GU,and then other GUs receive the information in a multi-hop manner.To minimize the total delay while ensuring that all GUs receive the information,we decouple it into three subproblems according to the time division on the topology:For the cluster-head selection,we adopt the Whale Optimization Algorithm(WOA) to imitate the hunting behavior of whales by abstracting the UAVs and cluster-heads into whales and preys,respectively;For the D2D multi-hop link establishment,we make the best of social relationships between GUs,and propose a node mapping algorithm based on the balanced spanning tree(BST) with reconfiguration to minimize the number of hops;For the dynamic connectivity maintenance,Restricted Q-learning(RQL) is utilized to learn the optimal multicast timeslot.Finally,the simulation results show that our proposed algorithms perfor better than other benchmark algorithms in the dynamic scenario.

A novel energetic framework with the combination of 5,6-fused triazolo-triazine and nitropyrazole-tetrazole for energy-stability balanced explosive

In recent years,the introduction of fused rings own high density and low sensitivity has promoted the development of energetic materials.However,the development of energetic compounds containing fused and bridged rings by introducing multiple nitrogen heterocycles at different sites of fused rings is still difficult to progress,which seriously limits the emergence of advanced energetic compounds.In this study,a series of energetic materials choosing different nitrogen rich heterocycles at the vacancies of the fused ring,i.e.,neutral compound 5,6 and their ionic derivatives(compounds 7-12)were designed and synthesized.Compounds 5 and 6 were further confirmed by single crystal X-ray diffraction,while the crystal analysis and theoretical calculations were carried out to explore the relationship between crystal structure and physicochemical properties.All of the newly synthesized compounds(5-12)are insensitive to mechanical stimulation(IS>40 J;FS≥342 N)and they own the high detonation velocity(D:8322-9075 m/s).Notably,hydrazine salt 11 own the higher detonation velocity(9075 m/s)and powder density(1.83 g/cm^(3)),but exhibits lower sensitivity(IS>40 J)than the classical energetic compound RDX(8795 m/s,1.80 g/cm^(3),7.5 J).It is obvious that the combination of 5,6-fused triazolo-triazine and nitropyrazole-tetrazole may be a new energetic skeleton for synthesising the heterocyclic compounds with balanced energy-stability.

Improved Load-Balanced Clustering for Energy-Aware Routing(ILBC-EAR)in WSNs

Sensors are considered as important elements of electronic devices.In many applications and service,Wireless Sensor Networks(WSNs)are involved in significant data sharing that are delivered to the sink node in energy efficient man-ner using multi-hop communications.But,the major challenge in WSN is the nodes are having limited battery resources,it is important to monitor the consumption rate of energy is very much needed.However,reducing energy con-sumption can increase the network lifetime in effective manner.For that,clustering methods are widely used for optimizing the rate of energy consumption among the sensor nodes.In that concern,this paper involves in deriving a novel model called Improved Load-Balanced Clustering for Energy-Aware Routing(ILBC-EAR),which mainly concentrates on optimal energy utilization with load-balanced process among cluster heads and member nodes.For providing equal rate of energy consumption among nodes,the dimensions of framed clusters are measured.Moreover,the model develops a Finest Routing Scheme based on Load-Balanced Clustering to transmit the sensed information to the sink or base station.The evaluation results depict that the derived energy aware model attains higher rate of life time than other works and also achieves balanced energy rate among head node.Additionally,the model also provides higher throughput and minimal delay in delivering data packets.

Glycemic Index of a Diabetes-Specific Nutritional Powder: An Open-Label Study in Healthy Indian Adults

Background: A balanced diet with a low glycemic index (GI) plays an important role in controlling and managing type 2 diabetes mellitus (T2DM). Here, we compared the GI of 2 flavors (vanilla and chocolate) of diabetes-specific nutritional (DSN) supplements to its comparator in healthy Indian adults under fasting conditions. Methods: This study was a 39-day open-label, non-comparative, single-center trial involving healthy adults aged between 18 to 45 years. The subjects received equal doses of 2 DSN powder (Treatments A and B), the comparator product (Treatment C), and dextrose monohydrate as a reference (Treatment R). Doses were administered as per the dosing schedule, after an overnight fast for 10 hours, with 2 intervening non-dosing days. Blood samples were collected on the dosing days to assess changes in capillary blood glucose levels. The primary endpoint of the study was the mean GI of Treatments A, B, and C (Defined as low: GI ≤ 55;medium: 55 GI ≤ 70;High: GI > 70), generated using the incremental area under the curve (AUCi) methodology. Safety was assessed throughout the study. Values of all study parameters were represented in ±SD or standard deviation. Results: Fourteen adult male subjects with a mean age of 29.42 ± 4.46 years, and a body mass index of 22.0 ± 1.95 Kg/m2, were enrolled in the study. The mean AUCi for treatments A, B, and C were 104 ± 10, 111 ± 12, and 87 ± 12 mmol min/L, respectively and for Treatment R it was 276 ± 16, 319 ± 28 and 338 ± 25 mmol min/L for Days 1, 6 and 8, respectively. The mean GI of Treatment A was 33 ± 3, Treatment B was 35 ± 3 and Treatment C was 29 ± 5;all GI means were ≤55. Mild adverse events were reported in 2 (14.3%) subjects. No serious adverse events or deaths were reported in the study. All treatments were well tolerated by the subjects. Conclusion: The glycemic index of both test products and comparator was low (i.e., GI 55) as per ISO 26642:2010 standard.

Genetic-Chicken Swarm Algorithm for Minimizing Energy in Wireless Sensor Network

Wireless Sensor Network(WSN)technology is the real-time applica-tion that is growing rapidly as the result of smart environments.Battery power is one of the most significant resources in WSN.For enhancing a power factor,the clustering techniques are used.During the forward of data in WSN,more power is consumed.In the existing system,it works with Load Balanced Cluster-ing Method(LBCM)and provides the lifespan of the network with scalability and reliability.In the existing system,it does not deal with end-to-end delay and deliv-ery of packets.For overcoming these issues in WSN,the proposed Genetic Algo-rithm based on Chicken Swarm Optimization(GA-CSO)with Load Balanced Clustering Method(LBCM)is used.Genetic Algorithm generates chromosomes in an arbitrary method then the chromosomes values are calculated using Fitness Function.Chicken Swarm Optimization(CSO)helps to solve the complex opti-mization problems.Also,it consists of chickens,hens,and rooster.It divides the chicken into clusters.Load Balanced Clustering Method(LBCM)maintains the energy during communication among the sensor nodes and also it balances the load in the gateways.The proposed GA-CSO with LBCM improves the life-span of the network.Moreover,it minimizes the energy consumption and also bal-ances the load over the network.The proposed method outperforms by using the following metrics such as energy efficiency,ratio of packet delivery,throughput of the network,lifetime of the sensor nodes.Therefore,the evaluation result shows the energy efficiency that has achieved 83.56%and the delivery ratio of the packet has reached 99.12%.Also,it has attained linear standard deviation and reduced the end-to-end delay as 97.32 ms.

On Answering the Question Related to the Legal Regulation of Working Hours in the New Era:Western Experience and Chinese Approach

The popularity of flexible working hours around the world has slowed down the historical trend of reducing working hours.It even shows signs of regression.Whether and how to guide the cur-rent society with flexible working hours to return to the historical track of reducing working hours,improve the quality of working hours,and promote a smooth transition from the era of traditional standard work-ing hours to the era of flexible working hours has become a question related to the legal regulation of working hours in the new era.In this regard,although Western countries have proposed new regulatory concepts and carried out legislative practices with distinctive charac-teristics,the limitations of legal regulation capabilities have prevented them from proposing a package of institutional solutions.The advan-tage of China in the ability of legal regulation of working hours has been gradually formed in the legislation on working hours unnder the leadership of the CPC in the past century.It enables China to break through the limitations of the West and propose a Chinese approach to answer the question of the legal regulation of working hours in the new era from three aspects:limiting the extension of working hours,improving the quality of flexible working hours,and optimizing the funnctions of the multi-funnctional regulatory system for working hours.

Effects of N,P and K Fertilizers on Photosynthetic Characteristics of Mulberry

[Objective] The aim was to research the effects of N, P and K fertilizers on photosynthetic characteristics of mulberry. [Method] In the test, Chuan 826, a va- riety of mulberry, was taken as an example to explore the relationships of chloro- phyll content, leaf area index, net photosynthetic rate, stomatal conductance of leaf, CO2 concentration of cells in leaves and transpiration rate with N, P and K fertilizers at different quantities. [Result] N, P and K fertilizers at different quantities have ef- fects on photosynthetic indices. In detail, N, P and K fertilizer at appropriate quanti- ties enhanced LAI, Chla＋b, Pn, Cond and Tr, Ci of mulberry leaves in control group without fertilizers was significantly higher than that in treatment groups. N, P and K at proper quantities （N at 600 kg/hm2, P at 210 kg/hm2 and K at 300 kg/hm2） would keep functional leaves well and higher photosynthetic period for a long term. [Conclusion] The research explored adjustment of photosynthetic characteristics and differ- ent treatments on photosynthesis of mulberry, providing reference for construction of excellent and highly-qualified mulberry garden.

A4~12GHz Wideband Balanced MIC Power Amplifier

A 4-12GHz wideband power amplifier,using a balanced configuration with a strip line Lange coupler, is designed and fabricated. This power amplifier shows a maximum continuous wave output power of 29.5dBm at 8GHz center frequency with an associated gain of 8.5dB and a gain flatness of ＋ /- 0.6dB in the 4-12GHz frequency range.

Effects of Balanced Fertilization on Mulberry Leaf Quality and Its Active Substance Content

This paper study the effect of nitrogen （N, X1）, phosphorus （P, X2） and potassium （K, X3） in different amounts on crude protein, soluble sugar, total flavonoid and 1-deoxynojirimycin contents in mulberry leaves, with mulberry trees in spring and autumn as the material and as per ＂3414＂ experimental design. The results showed that the qualities and active substance content of mulberry leaves changed from increasing to decreasing with its development; crude protein and solu-ble sugar achieved the peak on August 20; total flavonoid and 1-deoxynojirimycin was the highest on May 15. Fertilizations with N, P and K fertilizers at different amounts had significant effects on quality of mulberry leaf and content of active substances. Specifically, as fertilizer amount increased, the content of active sub- stances grew dramatically and achieved the highest at level 2 （X^2X=X~_）. Based on fertilizer effect functions of objective yield, the recommended amounts of N, P and K fertilizers based on crude protein, soluble sugar, flavonoid content and DNJ in test sites were 718.46, 220.11 and 305.23 kg/hm2, when the highest of crude protein in mulberry leaf was 1 813.83 kg/hm2. When N, P and K fertilizers were recommended at 666.54, 204.41 and 243.18 kg/hm2, soluble sugar in mulberry leaf achieved the peak at 1 042.65 kg/hm2. When N, P and K fertilizers were at 675.96, 326.49 and 462.90 kg/hm2, flavonoid content achieved the maximum at 147.90 kg/hm2. When N, P and K fertilizers were at 720.9, 225.11 and 323.63 kg/hm2, DNJ content was the highest at 13.55 kg/hm2.

Effects of Slow-release Fertilizer and Balanced Fertilization on Nitrogen, Phosphorus and Potassium Uptake in Peppers

Field plot experiment was conducted to study the effects of two slow-re- lease fertilizers and balanced fertilization on dry matter accumulation, yield, fertilizer use efficiency, nitrogen, phosphorus and potassium uptake of peppers at Jiangna Town, Yanshan County, Yunnan Province in 2011. The results showed that the dry matter accumulation in dried pepper plant, pepper yield, nitrogen, phosphorus, potassium uptake in peppers were significantly increased in all the fertilizer treat- ments, compared with those in control （no fertilizer）. Compared with conventional fertilization, balanced fertilization, slow-release compound fertilizer and slow-release urea fertilizer significantly increased dried pepper economic output by 20.94%, 17.5% and 14.54%, nitrogen uptake in dried peppers by 21.53%,18.46% and 13.19%, phosphorus uptake in dried peppers by 14.08%, 15.76% and 10.44%, potassium uptake in dried peppers by 22.66%, 15.73% and 16.28%; they also in- creased nitrogen and potassium use efficiency, but reduced potassium use efficiency due to the increased potassium addition. In treatments with balanced fertilization, slow-release compound fertilizer and slow-release urea fertilizer, the nitrogen utiliza- tion was 5.84%, 7.14% and 8.33% higher and the phosphorus utilization was 3.32%, 3.27% and 2.47% higher than those in treatment with conventional fertiliza- tion. In addition, the nitrogen application could be reduced by 20%-50% by bal- anced fertilization and the two slow-release fertilizers, thereby reducing environmen- tal pollution. Slow-release fertilizers could also reduce the frequency of fertilization and labor costs.

Effect of Nitrogen, Phosphorus and Potassium on the Content and Yield of DNJ of Mulberry Leaves in Spring

[Objective] This study aimed to scientifically improve the 1-deoxynojimycin （DNJ） yield of mulberry leaves in spring. [Method] ＂3414＂ experimental design was adopted to investigate the effects of different fertilizer application rates of nitrogen, phosphorus and potassium on the DNJ content in mulberry leaves. The regression relationship was further simulated with DNJ yield as the objective function and fertil- izer application rates of nitrogen, phosphorus and potassium as the regulatory factors. [Result] The results showed that nitrogen, phosphorus and potassium all have great effects on the DNJ content in mulberry leaves at different parts of mulberry tree （Morus alba）; the DNJ content in mulberry leaves increases with the increasing single-factor fertilizer application rate and reaches the maximum under N2P2K2 level; different fertilizer application rates and combinations of nitrogen, phosphorus and potassium can significantly affect the DNJ content in mulberry leaves; according to the simulated fertilizer effect function, the optimal economic yield of total DNJ in mul- berry leaves was 23.23 kg/hm^2, the recommended fertilization indicators were 286.11 kg/hm^2 N, 95.22 kg/hm^2 P2O5 and 159.62 kg/hm^2 K20. [Conclusion] After confirmation in productive practice, this optimal fertilization program can provide reference for the construction of mulberry plantation with high yield and high quality of DNJ.

On the construction of cryptographically strong Boolean functions with desirable trade-off

This paper proposes a practical algorithm for systematically generating strong Boolean functions (f:GF(2) n →GF(2)) with cryptographic meaning. This algorithm takes bent function as input and directly outputs the resulted Boolean function in terms of truth table sequence. This algorithm was used to develop two classes of balanced Boolean functions, one of which has very good cryptographic properties:nl(f)=2 2k?1?2k+2k?2 (n=2k), with the sum-of-squares avalanche characteristic off satisfying σf=24k+23k+2+23k-2 and the absolute avalanche characteristic off satisfying σf=24k+23k+2+23k-2. This is the best result up to now compared to existing ones. Instead of bent sequences, starting from random Boolean functions was also tested in the algorithm. Experimental results showed that starting from bent sequences is highly superior to starting from random Boolean functions. Key words Boolean functions - Bent sequences - Nonlinearity - GAC - PC - Balancedness Document code A CLC number TP301.6

Establishment of a Mathematical Model for Mulberry Balanced Fertilization in Hilly Areas of Sichuan Province

In order to increase mulberry leaf yield and production efficiency in hilly areas of Sichuan Province through scientific fertilization,＂3414＂,a quadratic regression design for modern fertilization,was employed to simulate the regression relationship between mulberry leaf yield and major fertilizer elements including nitrogen（N）,phosphor（P） and potassium（K） among which mulberry leaf yield was the objective function and N,P and K were the regulatory factors to fertilization level.As a result,7 types of ternary,binary and monadic quadratic fertilizer effect functions of N,P and K fertilizer elements were established.The weight of fertilizer factors in the optimal mulberry leaf yield obtained by various types of functions was in decreasing order of KPKPNPKNKNNP,and the weight of fertilizer factors in the ratio of leaf yield to input was in decreasing order of K〉PK〉NPK〉P〉NK〉NP〉N.To be specific,the ternary quadratic fertilizer effect function（Y=20 313＋0.25X1＋43.48 X2＋34.47X3-0.01X1^2-0.14X2^2-0.06X3^2＋0.05X1X2＋0.02X1X3-0.07X2X3,in which X1,X2 and X3 indicate the fertilizer factors N,P and K,respectively） was a model containing all factors,thereby being a recommended fertilization program for mulberry field.Single factor effect analysis indicated that K fertilizer had the highest influence on mulberry leaf yield and ratio of leaf yield to input.Therefore,among all the simulation functions,the monadic quadratic fertilizer effect function of K fertilizer factor（Y=25 002.27＋44.728X3-0.084X32） leads to the optimal leaf yield and maximum ratio of leaf yield to input.By using the optimal fertilization program with 600 kg/hm2 N,210 kg/hm2 P2O5 and 254.33 kg/hm2 K2O,the optimal economic leaf yield obtained is 30 945.00 kg/hm2,the cost of fertilizer input is 4 403.65 yuan/hm2,and the ratio of leaf yield to input is as high as 17.57.After verification by production practices,the recommended fertilization indicators in the optimal mulberry fertilization program can provide reference for the construction of high-yield mulberry field in hilly areas of Sichuan Province.

Cold Chain Logistics Equipment Management and Control Based on Internet of Things

The status and supporting policies of cold chain logistics equipment man- agement and control in China were described. The connotation of Internet of Things and its impact on cold chain logistics equipment management and control were ana- lyzed from external form to internal nature. Through introducing the value chain and relevant equipments of cold chain logistics, the correlation between the main technologies in Internet of Things and the common indices for cold chain logistics equipment management and control was analyzed in detail. The application values of Internet of Things technologies in cold chain logistics equipment management and control were illustrated, including the sample analysis on the application of radio-frequency identification （RFID）. After the establishment of BSC performance evaluation index system of cold chain logistics equipment management and control, the optimization measures and suggestions on cold chain logistics equipment management and control under Internet of Things were put forward.

3D B-FFE序列在脑积水MRI检查中的应用

目的:探讨3D平衡全稳态快速场梯度回波(3DBalancedFastFieldEcho以下简称3DB-FFE)序列在脑积水成像中的临床应用价值。材料与方法:采用飞利浦Achieva1.5T双梯度超导型磁共振设备对50例脑室系统有积水的患者进行3DB-FFE序列脑室系统成像扫描。比较该方法与常规T1WI、T2WI显示中脑导水管和室间孔形态的效果。结果:50例患者3DB-FFE序列图像均清晰显示脑室系统,对中脑导水管和室间孔的扩张、狭窄、梗阻的程度和形态与常规SE序列T1WI、T2WI显示效果相比较,3DB-FFE序列有明显优越性。结论:3DB-FFE序列脑室成像扫描能清晰显示脑室积水情况,为临床确诊和治疗提供可靠的依据,可作为一种MR脑室积水成像的新方法。