232 research outputs found
A new record for Iran of Dolichogenidea appellator (Hym.: Braconidae: Microgastrinae), a larval endoparasitoid of diamondback moth, Plutella xylostella (Lep.: Plutellidae)
Observational notes and photographs taken in the course of rearing Euceros albitarsus Curtis
and E. pruinosus (Gravenhorst) in captivity from the egg stage are given. The bizarre biology of these
obligate hyperparasitoids involves a planidial larval stage that attaches to caterpillars or sawfly larvae,
followed by a short phase of internal parasitism of a primary parasitoid if already or subsequently present,
followed in turn by the principle growth period of external parasitism on the primary parasitoid, as shown
by Tripp (1961). Observations on aspects of this that were not illustrated by Tripp are given and, although
these transitions are not fully elucidated here, it is speculated that the number of larval instars had hitherto
been overestimated. Investigations on the behaviour and fate of the planidial phase suggest that it is best
able to transfer to primary parasitoids that are associated with the prepupal state of the lepidopteran host.
Planidia on caterpillars that are not themselves parasitised end up in the host pupa, usually occupying the
subalar cavity of the exuvial space (that is, just below the pupal cuticle at the wing cases), but do not
develop further in the absence of a primary parasitoid. A summary of some aspects of the biology of
Euceros that are not yet understood is given: the main uncertainties are the number and feeding positions
of larval instars, the timing and nature of the planidium’s transfer to the primary parasitoid, and the func-
tion of the unusual male antenn
Automated parametrical antenna modelling for ambient assisted living applications
In this paper a parametric modeling technique for a fast polynomial
extraction of the physically relevant parameters of inductively coupled
RFID/NFC (radio frequency identification/near field communication)
antennas is presented. The polynomial model equations are obtained by means
of a three-step procedure: first, full Partial Element Equivalent Circuit
(PEEC) antenna models are determined by means of a number of parametric
simulations within the input parameter range of a certain antenna class.
Based on these models, the RLC antenna parameters are extracted in a
subsequent model reduction step. Employing these parameters, polynomial
equations describing the antenna parameter with respect to (w.r.t.) the
overall antenna input parameter range are extracted by means of polynomial
interpolation and approximation of the change of the polynomials'
coefficients. The described approach is compared to the results of a
reference PEEC solver with regard to accuracy and computation effort
Effects of acupressure at the hugo point (LI4) on labor pain and duration of delivery in nulliparous women
Introduction: Most women have experienced child birth and its pain, which is inevitable. If this pain is not controlled it leads to prolonged labor and injury to the mother and fetus. This study was conducted to identify the effect of acupressure on sanyinjiao and hugo points on delivery pain in nulliparous women. Methods:This was a randomized controlled clinical trial on 84 nulliparous women in hospitals of Ardebil, Iran. The participants were divided by randomized blocks of 4 and 6 into two groups. The intervention was in the form of applying pressure at sanyinjiao and hugo points based on different dilatations. The intensity of the pain before and after the intervention was recorded by visual scale of pain assessment. To determine the effect of pressure on the intensity of labor pain, analytical descriptive test was conducted in SPSS (version 13). Results:There was a significant decrease in mean intensity of pain after each intervention in the experimental group with different dilatations (4, 6, 8, and 10 cm). Moreover, the Student’s independent t-test results indicated that the mean intensity of pain in the experimental group after the intervention in all four dilatations was significantly lower than the control group. Repeated measures ANOVA test indicated that in both experimental and control groups in four time periods, there was a statistically significant difference. Conclusion:Acupressure on sanyinjiao and hugo points decreases the labor pain. Therefore, this method can be used effectively in the labor process
An Energetic AGN Outburst Powered by a Rapidly Spinning Supermassive Black Hole or an Accreting Ultramassive Black Hole
Powering the 10^62 erg nuclear outburst in the MS0735.6+7421 cluster central
galaxy by accretion implies that its supermassive black hole (SMBH) grew by
~6x10^8 solar masses over the past 100 Myr. We place upper limits on the amount
of cold gas and star formation near the nucleus of <10^9 solar masses and <2
solar masses per year, respectively. These limits imply that an implausibly
large fraction of the preexisting cold gas in the bulge must have been consumed
by its SMBH at the rate of ~3-5 solar masses per year while leaving no trace of
star formation. Such a high accretion rate would be difficult to maintain by
stellar accretion or the Bondi mechanism, unless the black hole mass approaches
10^11 solar masses. Its feeble nuclear luminosities in the UV, I, and X-ray
bands compared to its enormous mechanical power are inconsistent with rapid
accretion onto a ~5x10^9 solar mass black hole. We suggest instead that the AGN
outburst is powered by a rapidly-spinning black hole. A maximally-spinning,
10^9 solar mass black hole contains enough rotational energy, ~10^62 erg, to
quench a cooling flow over its lifetime and to contribute significantly to the
excess entropy found in the hot atmospheres of groups and clusters. Two modes
of AGN feedback may be quenching star formation in elliptical galaxies centered
in cooling halos at late times. An accretion mode that operates in gas-rich
systems, and a spin mode operating at modest accretion rates. The spin
conjecture may be avoided in MS0735 by appealing to Bondi accretion onto a
central black hole whose mass greatly exceeds 10^10 solar mass. The host
galaxy's unusually large, 3.8 kpc stellar core radius (light deficit) may
witness the presence of an ultramassive black hole.Comment: Accepted for publication in ApJ. Modifications: adopted slightly
higher black hole mass using Lauer's M_SMBH vs L_bulge relation and adjusted
related quantities; considered more seriously the consequences of a
ultramassive black hole, motivated by new Kormendy & Bender paper published
after our submission; other modifications per referee comments by Ruszkowsk
Intelligent Tuned Harmony Search for Solving Economic Dispatch Problem with Valve-point Effects and Prohibited Operating Zones
Economic dispatch with valve point effect and Prohibited Operating Zones (POZs) is a non-convex and discontinuous optimization problem. Harmony Search (HS) is one of the recently presented meta-heuristic algorithms for solving optimization problems, which has different variants. The performances of these variants are severely affected by selection of different parameters of the algorithm. Intelligent Tuned Harmony Search (ITHS) is a recently developed variant, which mitigates the drawbacks of parameter initializing by maintaining a proper balance between diversification and intensification throughout the search process. The proposed method is applied to five different cases of power systems and the effectiveness, feasibility, and robustness of method is explored through the comparison with reported results in recent literature. First three case studies are systems with 3, 13, and 40-units, considering valve- point effect. The fourth and fifth cases are six and 15-generation unit taking into account generator constraints including POZs, ramp rate limit and transmission line losses which is a challenging Economic Dispatch (ED) problem due to restriction in search space. Computation results imply the efficiency of the proposed method toward other optimization methods reported in recent literature, judged in terms of the objective function value and solution robustness
Unit commitment by a fast and new analytical non-iterative method using IPPD table and “λ-logic” algorithm
Many different methods have been presented to solve unit commitment (UC) problem in literature with different advantages and disadvantages. The need for multiple runs, huge computational burden and time, and poor convergence are some of the disadvantages, where are especially considerable in large scale systems. In this paper, a new analytical and non-iterative method is presented to solve UC problem. In the proposed method, improved pre-prepared power demand (IPPD) table is used to solve UC problem, and then analytical “λ-logic” algorithm is used to solve economic dispatch (ED) sub-problem. The analytical and non-iterative nature of the mentioned methods results in simplification of the UC problem solution. Obtaining minimum cost in very small time with only one run is the major advantage of the proposed method. The proposed method has been tested on 10 unit and 40-100 unit systems with consideration of different constraints, such as: power generation limit of units, reserve constraints, minimum up and down times of generating units. Comparing the simulation results of the proposed method with other methods in literature shows that in large scale systems, the proposed method achieves minimum operational cost within minimum computational time
Advanced parametrical modelling of 24 GHz radar sensor IC packaging components
This paper deals with the development of an advanced
parametrical modelling concept for packaging components of a 24 GHz radar
sensor IC used in automotive driver assistance systems. For fast and
efficient design of packages for system-in-package modules (SiP), a
simplified model for the description of parasitic electromagnetic effects
within the package is desirable, as 3-D field computation becomes inefficient
due to the high density of conductive elements of the various signal paths
in the package. By using lumped element models for the characterization of
the conductive components, a fast indication of the design's signal-quality
can be gained, but so far does not offer enough flexibility to cover the
whole range of geometric arrangements of signal paths in a contemporary
package. This work pursues to meet the challenge of developing a flexible
and fast package modelling concept by defining <i>parametric</i> lumped-element models for
all basic signal path components, e.g. bond wires, vias, strip lines, bumps
and balls
A new record for Iran of Dolichogenidea appellator (Hym.: Braconidae: Microgastrinae), a larval endoparasitoid of diamondback moth, Plutella xylostella (Lep.: Plutellidae)
طی مطالعاتی که در سال 1390 روی بید کلم، Plutella xylostella (L.)، در استان اصفهان انجام شد، یک گونه زنبور پارازیتوئید به نام Dolichogenidea appellator (Telenga) از پرورش لاروهای بید کلم جمعآوریشده از مزارع کلمپیچ، واقع در مرکز تحقیقات کشاورزی و منابع طبیعی استان اصفهان بهدست آمد که برای فون ایران جدید است. این زنبور، علاوهبر بید کلم، بالپولکداران دیگری از خانواده Gelechiidae، نظیر Scrobipalpa salinella (Zeller) و Phthorimaea operculella (Zeller)، را نیز پارازیته میکند
STATCOM Optimal Allocation in Transmission Grids Considering Contingency Analysis in OPF Using BF-PSO Algorithm
In this paper, a combinational optimization algorithm is introduced to obtain the best size and location of Static Compensator (STATCOM) in power systems. Its main contribution is considering contingency analysis where lines outages may lead to infeasible solutions especially at peak loads and it commonly can be vanished by load-shedding. The objective of the proposed algorithm is firstly to prevent infeasible power flow solutions without undesired load-shedding, which is critical in contingency analysis; and secondly to mitigate overall power losses and costs. Moreover, active and reactive powers generation costs are considered in the proposed objective function. Since there are various constraints such as lines outages number, cost and their duration that must be taken to account, Bacterial Foraging oriented by Particle Swarm Optimization (BF-PSO) algorithm combined with Optimal Power Flow (OPF) is used to solve and overcome the complexity of this combinational nonlinear problem. In order to validate the accuracy of the proposed method, two test systems, including IEEE 30 bus standard system and Azarbaijan regional power system of Iran, are applied in simulation studies. All obtained optimization results show the effectiveness of the suggested combinational method in loss and cost reduction and preventing load-shedding
Improving the Effect of Electric Vehicle Charging on Imbalance Index in the Unbalanced Distribution Network Using Demand Response Considering Data Mining Techniques
With the development of electrical network infrastructure and the emergence of concepts such as demand response and using electric vehicles for purposes other than transportation, knowing the behavioral patterns of network technical specifications to manage electrical systems has become very important optimally. One of the critical parameters in the electrical system management is the distribution network imbalance. There are several ways to improve and control network imbalances. One of these ways is to detect the behavior of bus imbalance profiles in the network using data analysis. In the past, data analysis was performed for large environments such as states and countries. However, after the emergence of smart grids, behavioral study and recognition of these patterns in small-scale environments has found a fundamental and essential role in the deep management of these networks. One of the appropriate methods in identifying behavioral patterns is data mining. This paper uses the concepts of hierarchical and k-means clustering methods to identify the behavioral pattern of the imbalance index in an unbalanced distribution network. For this purpose, first, in an unbalanced network without the electric vehicle parking, the imbalance profile for all busses is estimated. Then, by applying the penetration coefficient of 25 and 75 for electric vehicles in the network, charging/discharging effects on the imbalance profile is determined. Then, by determining the target cluster and using demand response, the imbalance index is improved. This method reduces the number of busses competing in demand response programs. Next, using the concept of classification, a decision tree is constructed to minimize metering time
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