An Indexing Method of Continuous Spatiotemporal Queries for Stream Data Processing Rules of Detected Target Objects

Real-time performance is important in rule-based continuous spatiotemporal query processing for risk analysis and decision making of target objects collected by sensors of combat vessels. The existing Rete algorithm, which creates a compiled node link structure for executing rules, is known to be the best. However, when a large number of rules are to be processed and the stream data to be performed are large, the Rete technique has an overhead of searching for rules to be bound. This paper proposes a hashing indexing technique for Rete nodes to the overhead of searching for spatiotemporal condition rules that must be bound when rules are expressed in a node link structure. A performance comparison evaluation experiment was conducted with Drool, which implemented the Rete method, and the method that implemented the hash index method presented in this paper. For performance measurement, processing time was measured for the change in the number of rules, the change in the number of objects, and the distribution of objects. The hash index method presented in this paper improved performance by at least 18% compared to Drool.

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The Urgent Need for River Health Biomonitoring Tools for Large Tropical Rivers in Developing Countries: Preliminary Development of a River Health Monitoring Tool for Myanmar Rivers

Water ◽

10.3390/w12051408 ◽

2020 ◽

Vol 12 (5) ◽

pp. 1408 ◽

Cited By ~ 4

Author(s):

Nyein Thandar Ko ◽

Phil Suter ◽

John Conallin ◽

Martine Rutten ◽

Thom Bogaard

Keyword(s):

Developing Countries ◽

Asian Countries ◽

Anthropogenic Pressures ◽

River Health ◽

Index Method ◽

Indexing Methods ◽

Indexing Method ◽

Additional Testing ◽

Best Fit ◽

Country Specific

Anthropogenic pressures such as river infrastructure, agriculture and power generation are rapidly increasing in Southeast Asia, aimed at providing food security within the region. However, this will lead to unintended river health consequences, and, currently, most Southeast Asian countries have no country-specific tools for monitoring river health. In Myanmar, one of Southeast Asia’s poorest and most rapidly developing countries, no country-specific tools exist, and there is an urgent need to provide tools that can inform better management and trade-off decision making. This research evaluated three rapid macroinvertebrate bioassessment methods under Myanmar conditions. The objective of the research was to assess the applicability of existing internationally accepted indexing methods for use in Myanmar. Through taxa identification in the laboratory and statistical analysis, it was concluded that the method with the best fit for Myanmar taxa is The Asia Foundation index method, although differences were small. This Asia Foundation method is comparable to the Australian Waterwatch method but includes a family present in our samples that is not included in the Waterwatch method. We then modified this method to include Myanmar taxa not recorded in The Asia Foundation method. The modified index method could be further developed into a Myanmar specific tool for widespread use potentially in combination with the also tested miniSASS, a much easier order-based method better suitable for non-professionals. We recommend additional testing using sites on other rivers across the country to establish a professional indexing method for Myanmar.

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Performance Comparison of PD Data Acquisition Techniques for Condition Monitoring of Medium Voltage Cables

Energies ◽

10.3390/en13164272 ◽

2020 ◽

Vol 13 (16) ◽

pp. 4272 ◽

Cited By ~ 1

Author(s):

Muhammad Shafiq ◽

Ivar Kiitam ◽

Kimmo Kauhaniemi ◽

Paul Taklaja ◽

Lauri Kütt ◽

...

Keyword(s):

Data Acquisition ◽

Condition Monitoring ◽

Partial Discharge ◽

Performance Comparison ◽

Practical Implementation ◽

Monitoring Methods ◽

Medium Voltage ◽

Cable Networks ◽

Improved Performance ◽

Diagnostic Capabilities

Already installed cables are aging and the cable network is growing rapidly. Improved condition monitoring methods are required for greater visibility of insulation defects in the cable networks. One of the critical challenges for continuous monitoring is the large amount of partial discharge (PD) data that poses constraints on the diagnostic capabilities. This paper presents the performance comparison of two data acquisition techniques based on phase resolved partial discharge (PRPD) and pulse acquisition (PA). The major contribution of this work is to provide an in-depth understanding of these techniques considering the perspective of randomness of the PD mechanism and improvements in the reliability of diagnostics. Experimental study is performed on the medium voltage (MV) cables in the laboratory environment. It has been observed that PRPD based acquisition not only requires a significantly larger amount of data but is also susceptible to losing the important information especially when multiple PD sources are being investigated. On the other hand, the PA technique presents improved performance for PD diagnosis. Furthermore, the use of the PA technique enables the efficient practical implementation of the continuous PD monitoring by reducing the amount of data that is acquired by extracting useful signals and discarding the silent data intervals.

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HD-Tree: An Efficient High-Dimensional Virtual Index Structure Using a Half Decomposition Strategy

Algorithms ◽

10.3390/a13120338 ◽

2020 ◽

Vol 13 (12) ◽

pp. 338

Author(s):

Ting Huang ◽

Zhengping Weng ◽

Gang Liu ◽

Zhenwen He

Keyword(s):

Hash Table ◽

Index Structure ◽

High Dimensional ◽

Sequential Search ◽

Storage Space ◽

Hash Tables ◽

Time Performance ◽

Indexing Method ◽

Point Data ◽

Better Than

To manage multidimensional point data more efficiently, this paper presents an improvement, called HD-tree, of a previous indexing method, called D-tree. Both structures combine quadtree-like partitioning (using integer shift operations without storing internal nodes, but only leaves) and hash tables (for searching for the nodes stored). However, the HD-tree follows a brand-new decomposition strategy, which is called half decomposition strategy. This improvement avoids the generation of nodes containing only a small amount of data and the sequential search of the hash table, so that it can save storage space while having faster I/O and better time performance when building the tree and querying data. The results demonstrate convincingly that the time and space performance of HD-tree is better than that of D-tree regardless of uniform or uneven data, which are less affected by data distribution.

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Functional programming with the FC++ library

Journal of Functional Programming ◽

10.1017/s0956796803004969 ◽

2004 ◽

Vol 14 (4) ◽

pp. 429-472 ◽

Cited By ~ 6

Author(s):

BRIAN MCNAMARA ◽

YANNIS SMARAGDAKIS

Keyword(s):

Data Structures ◽

Functional Programming ◽

Higher Order ◽

Performance Comparison ◽

Type Inference ◽

High Complexity ◽

Time Performance ◽

Order Of Magnitude ◽

Supporting Functional ◽

Higher Order Functions

We describe the FC++ library, a rich library supporting functional programming in C++. Prior approaches to encoding higher order functions in C++ have suffered with respect to polymorphic functions from either lack of expressiveness or high complexity. In contrast, FC++ offers full and concise support for higher-order polymorphic functions through a novel use of C++ type inference. The FC++ library has a number of useful features, including a generalized mechanism to implement currying in C++, a “lazy list” class which enables the creation of “infinite data structures”, a subtype polymorphism facility, and an extensive library of useful functions, including a large part of the Haskell Standard Prelude. The FC++ library has an efficient implementation. We show the results of a number of experiments which demonstrate the value of optimizations we have implemented. These optimizations have improved the run-time performance by about an order of magnitude for some benchmark programs that make heavy use of FC++ lazy lists. We also make an informal performance comparison with similar programs written in Haskell.

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Rotor Design and Optimization in Internal Lobe Pumps

Applied Mechanics Reviews ◽

10.1115/1.3101825 ◽

1997 ◽

Vol 50 (11S) ◽

pp. S133-S141 ◽

Cited By ~ 11

Author(s):

Giovanni Mimmi ◽

Paolo Pennacchi

Keyword(s):

Flow Rate ◽

Performance Comparison ◽

Definite Function ◽

Pump Design ◽

Design And Optimization ◽

Performance Indexes ◽

New Type ◽

Improved Performance ◽

Lobe Pump ◽

Rotor Curvature

The topic of this paper is the design of internal lobe pumps and their optimization which is based on specific performance indexes. Internal lobe pumps can be classified as different types depending on the shape of the lobe of the outer rotor. First, the design of internal lobe pumps with elliptical, sinusoidal, and polycircular lobe profiles is considered. The latter is a new type of lobe profile with special shape whose curvature follows a definite function. Then we introduce the performance indexes used for the comparison. Some of these indexes, such as the flow rate irregularity, are commonly used for performance comparison, while others, such as the specific slipping and the rotor curvature, are particularly suitable in this case. The comparisons are made with the circular type that had been analyzed by the authors in previous papers (see eg, Mimmi, Pannacchi, and Savi (1996), Internal Lobe Pump Design, Mechanics in design - Proc CSME Forum ’96, SA Meguid (ed), Toronto, Ontario, Canada). It is not easy to univocally state the superiority of one type with respect to the others, however, it is possible to notice that elliptical and polycircular types are comparable to the circular ones in terms of flow rate irregularity, but have improved performance in terms of specific slipping and rotor curvature.

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An Experimental Performance Comparison for Indexing Mobile Objects on the Plane

Intelligent and Knowledge-Based Computing for Business and Organizational Advancements ◽

10.4018/978-1-4666-1577-9.ch019 ◽

2012 ◽

pp. 340-358

Author(s):

S.Sioutas ◽

G. Papaloukopoulos ◽

K. Tsichlas ◽

Y. Manolopoulos

Keyword(s):

Experimental Evaluation ◽

Performance Comparison ◽

Value Distribution ◽

Lower Threshold ◽

Range Queries ◽

Access Method ◽

Experimental Performance ◽

Efficient Approach ◽

Mobile Objects ◽

Improved Performance

In this paper, the authors present a time-efficient approach to index objects moving on the plane in order to answer range queries about their future positions. Each object is moving with non small velocity u, meaning that the velocity value distribution is skewed (Zipf) towards in some range , where is a positive lower threshold. This algorithm enhances a previously described solution (Sioutas, Tsakalidis, Tsichlas, Makris, & Manolopoulos, 2007) by accommodating the ISB-tree access method as presented in Kaporis et al. (2005). Experimental evaluation shows the improved performance, scalability, and efficiency of the new algorithm.

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Real Time Performance Comparison of Buck Converter Circuit Controlled By Discrete Time PID, LQR and SMC Controllers in Continuous-Current Mode

Sakarya University Journal of Science ◽

10.16984/saufenbilder.467592 ◽

2019 ◽

pp. 1198-1206

Author(s):

Ömer ÖZDEMİR ◽

İrfan YAZICI

Keyword(s):

Real Time ◽

Discrete Time ◽

Current Mode ◽

Performance Comparison ◽

Buck Converter ◽

Time Performance ◽

Continuous Current ◽

Continuous Current Mode

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Su1041 A TIME PERFORMANCE COMPARISON BETWEEN MODERATE AND DEEP SEDATION FOR SCREENING COLONOSCOPIES IN OBESE PATIENTS WITH OBSTRUCTIVE SLEEP APNEA

Gastrointestinal Endoscopy ◽

10.1016/j.gie.2020.03.1887 ◽

2020 ◽

Vol 91 (6) ◽

pp. AB278

Author(s):

ivan M. columbus morales ◽

Randeep Kaur ◽

Taha Ashraf ◽

Faisal M. Nimri ◽

Simran Bhatti ◽

...

Keyword(s):

Obstructive Sleep Apnea ◽

Sleep Apnea ◽

Deep Sedation ◽

Performance Comparison ◽

Obese Patients ◽

Time Performance ◽

Obstructive Sleep

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NUMERICAL AND EXPERIMENTAL STUDY OF A TWO-STAGE SAVONIUS WIND TURBINE

Revista de Engenharia Térmica ◽

10.5380/reterm.v18i2.70794 ◽

2019 ◽

Vol 18 (2) ◽

pp. 52

Author(s):

L. B. Kothe ◽

A. P. Petry

Keyword(s):

Experimental Study ◽

Numerical Simulations ◽

Wind Turbine ◽

Vertical Axis ◽

Relative Difference ◽

Performance Comparison ◽

Speed Ratio ◽

Vertical Axis Wind Turbine ◽

Two Stage ◽

Index Method

This article presents a numerical and experimental study of vertical axis wind turbine performance comparison involving a two-stage Savonius rotor with similar parameters. The experimental study is conducted in the aerodynamic tunnel at the Fluid Mechanics Laboratory of the Federal University of Rio Grande do Sul. The aerodynamics rotors are manufactured by 3D prototyping technique. Numerical simulations are performed using the Finite Volumes Method performed by the solution of the Reynolds Averaged Navier-Stokes (RANS) and continuity equations using the SST k-ω turbulence model. The numerical domain is modeled in order to maintain the same characteristics of the experimental model. The mesh quality is evaluated through the GCI (Grid Convergence Index) method. The static and dynamic torque coefficients and the power coefficients are compared. The tests are made without blockage corrections due to the small blockage ratio from 7.5%. Results show that the turbine has a positive static torque coefficient for any rotor angles. The dynamic torque reaches the maximum value for a tip speed ratio (λ) of 0.2 for the experimental and numerical cases. The relative difference between the numerical simulations and the experimental results are between 3.8% and 13.4%.

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