scholarly journals Граничное значение поля, разделяющее области подкритических и глубоко подкритических видов СВЧ-разряда, зажигаемого на диэлектрической поверхности

2019 ◽  
Vol 89 (1) ◽  
pp. 64
Author(s):  
П.В. Булат ◽  
Л.П. Грачев ◽  
И.И. Есаков ◽  
А.А. Раваев
Keyword(s):  
Microwave Field ◽  
Microwave Discharge ◽  
Threshold Level ◽  
Propagation Direction ◽  
Plasma Region ◽  
Dielectric Tube ◽  
Microwave Beam ◽  
Inner Surface ◽  
And Control ◽  
Microwave Discharges

AbstractMicrowave discharges initiated by an electromagnetic (EM) vibrator and ignited on the inner surface of a dielectric tube in a quasi-optical EM beam are experimentally studied. A threshold level of the microwave field that separates domains of subcritical and deeply subcritical microwave discharges is determined in experiments. Experiments show that streamer channels of the subcritical discharge propagate from the initiator along the propagation direction of the EM wave and in the opposite direction under certain conditions. Variations in the power of the microwave beam can be used to change length of the plasma region of the subcritical discharge along the wave vector of the microwave beam and control the level of the EM energy absorbed in the plasma regions of the deeply subcritical microwave discharge.

scholarly journals Динамика горения пропан-воздушной газовой смеси при ее поджиге стримерным сверхвысокочастотным разрядом

2019 ◽  
Vol 89 (10) ◽  
pp. 1529
Author(s):  
П.В. Булат ◽  
Л.П. Грачев ◽  
И.И. Есаков ◽  
А.А. Раваев ◽  
Л.Г. Северинов
Keyword(s):  
Atmospheric Pressure ◽  
Discharge Plasma ◽  
Microwave Discharge ◽  
Combustion Process ◽  
Experimental Studies ◽  
Gaseous Mixture ◽  
Process Dynamics ◽  
Microwave Beam ◽  
Linearly Polarized ◽  
Transparent Tube

AbstractThe results of experimental studies of combustion of propane–air gaseous mixture when it was ignited by a microwave discharge have been described. The mixture with different propane content fills a sealed radio-transparent tube placed along the axis of a focused linearly polarized quasi-optical microwave beam at atmospheric pressure. Multi-point ignition of the mixture is carried out near one end of the tube by a pulsed microwave discharge with a surface-developed streamer structure. The growth of gas pressure in the tube as propane burned was recorded in the experiments. The microwave pulse energy being invested in high-temperature discharge plasma has been estimated in them. The minimum percentage of propane in the mixture at which the microwave discharge ignites it has been determined in experiments. The time dependence of the pressure increase in the tube as the propane burns determines the combustion process dynamics.

scholarly journals Anaemia in solitary acyanotic ventricular septal defect in comorbid with pneumonia or pulmonary hypertension: A retrospective study of 75 paediatric cases

F1000Research ◽  
2019 ◽  
Vol 8 ◽  
pp. 101
Author(s):  
Geoffrey Joseph Changwe ◽  
Haizhou Zhang ◽  
Hongxin Li ◽  
Zeeshan Farhaj ◽  
Marlvin Anemey Tewara ◽  
...  
Keyword(s):  
Pulmonary Hypertension ◽  
Retrospective Study ◽  
Young Children ◽  
Heart Defects ◽  
Threshold Level ◽  
Older Children ◽  
Surgical Closure ◽  
History Of ◽  
A Prospective Study ◽  
And Control

Background: Ventricular septal defects (VSD) are the second commonest congenital heart defects after bicuspid aortic valve. When left unrepaired, they can undergo spontaneous closure or elicit a spectrum of complications including pneumonia (PNA) or pulmonary hypertension (PH) with subsequent anaemia. In this retrospective study, we aim to establish and compare the prevalence of anaemia in patients with solitary acyanotic VSD in comorbid with PNA or PH. Methods: A total of 75 case files of patients with solitary acyanotic VSD, who underwent surgical closure or device occlusion had haemoglobin level analysed prior to the procedure. The cohort included patients with (history of) PNA and PH, and asymptomatic. The cohort included 27 females and 48 males with mean age and weight of 8.3±5.72 (3-24) months and 5.9±3.9 (2.7-17.8) kilograms, respectively. Depending on  associated complication and age, the cohort was divided: PNA (A), PH (B) and Control (C); and (I) young children (≥3-6≤) and (II) older children (>6-≤24) months. We used 95 and 105 grams per litre as haemoglobin lower threshold level for (I) and (II), respectively. Results: According to data analysis 27 patients (36%) in total had anaemia. Of the anaemia cohort 16 (59.3%) had PNA, 9 (33.3%) PH and 2 (7.4%) were asymptomatic. Of the cohort, 42 were young children, with anaemia prevalence of 19/42 (45.2%), while 24.2% of the older children had anaemia. Intergroup ANOVA independent sample t-test was significant (p<0.05). In addition, intergroup Tukey HSD test for haemoglobin: A/B (p>0.05), A/C (p<0.01), B/C (p<0.01).  Conclusion: Paediatric patients with acyanotic VSD in comorbid with PNA or PH are 8 and 4 times more susceptible to develop anaemia compared to asymptomatic counterparts. Susceptibility is even higher among young children (3-6months). However, a prospective study is needed to validate our findings.

scholarly journals Determination of economic threshold level for the timely management of cotton jassid Amrasca bigutulla (Ishida) on okra vegetable crop

2017 ◽  
Vol 9 (3) ◽  
pp. 1429-1433
Author(s):  
Sandeep Kaur ◽  
Amandeep Kaur ◽  
Gurpreet Kaur ◽  
A.K. Dhawan
Keyword(s):  
Pest Management ◽  
Management Practices ◽  
Threshold Level ◽  
Leaf Margin ◽  
Economic Threshold ◽  
Vegetable Crop ◽  
Pooled Data ◽  
Injury Grade ◽  
And Control

A field study was carried out at Vegetable Research Farm PAU, Ludhiana to determine the economic threshold level for the timely management of cotton jassid Amrasca bigutulla (Ishida) on okra vegetable crop. It was observed that significantly lowest jassid nymphal count per leaf in the pooled data (0.96 nymphs/leaf) were registered in the treatment where spray against jassid were given at 2 nymphs/leaf stage and first injury grade that is curling and yellowing of leaf margin as compared to others spray stages (1.54-1.72 nymphs/leaf) and unsprayed control (1.75 nymphs/leaf) significantly lowest jassid injury grade was also observed when spray stared at 2 nymphs/ leaf (0.58) and second spray stage curling and yellowing of leaf margin (0.65 nymphs/leaf) as against other spray stages (1.13 – 1.60 nymphs/leaf) and unsprayed control (1.63 nymphs/leaf). Maximum plant (110.33-110.44 cm) was also recorded as against other treatment (90.80 – 108.46 cm) and control (90.13cm). Total highest fruit yield (120.40-120.75) quintal /ha was also registered in these two treatments. Economic threshold level estimated for the management of cotton jassid on okra crop will help to develop an ecologically safe pest management practices against this pest.

Simulation of Street Light Pole Controller Routing with OMNeT++

2013 ◽  
Vol 401-403 ◽  
pp. 1976-1980
Author(s):  
Chun Guo Jing ◽  
Jun Wei Wang
Keyword(s):  
Routing Protocol ◽  
Propagation Direction ◽  
Lighting System ◽  
Monitoring And Control ◽  
Street Lighting ◽  
Routing Strategy ◽  
Path Discovery ◽  
Light Pole ◽  
And Control ◽  
Discovery Algorithms

In street lighting system, the light pole controllers were used to monitoring and control each street light. The controller nodes were installed at each lighting pole and make up a network with RTUs. In this paper, a randomly forwarding routing strategy was proposed based on the controller network features. The controller nodes were divided many clusters according to the substation power scope. In one cluster, the controller nodes topology is mainly star structure. When a controller node received a packet, it randomly delays a period of time and decides forwarding packet instead of immediately forwarding. The decision is based on the packet propagation direction and other nodes whether sending or not. The randomly forwarding routing protocol were simulated in OMNeT++ environment and compared with the flooding protocol. The results show that the delay of proposed protocol is lower than that of flooding. The proposed protocol also has some special features such as simple, not need to maintain net topology and complex path discovery algorithms.

Development of Robotic Spraying System in Narrow Space

2013 ◽  
Vol 442 ◽  
pp. 221-224
Author(s):  
Yan Chen ◽  
Wen Zhuo Chen ◽  
Ken Chen ◽  
Jun Yi Shao ◽  
Wei Ming Zhang
Keyword(s):  
High Pressure ◽  
Pressure Fluctuation ◽  
Feed System ◽  
Fluid System ◽  
Work Requirements ◽  
High Solid ◽  
Inner Surface ◽  
Narrow Space ◽  
And Control ◽  
Spray Gun

The coating of the intermediate coating on the inner surface in narrow space is characterized by high solid, high density, sedimentation. LVMP process is qualified and adopted to spray this high solid coating. The designed pressure feed system is composed of a fluid system and a pneumatic system. The former is used to feed coatings into the spray gun, circulate coating and agitate coating, while the latter is used to actuate and control the fluid system and provide high pressure air as cylinder air, atomization air and pattern air. The experiments show that the robotic spraying system could satisfy the work requirements including good stabilization, no settling, ignorable pressure fluctuation and fine atomization in narrow space.

A Theoretical Study of the Internal Forces in a Hydraulic Vane Pump with Hypertrochoid Curve in the Inner Surface of its Stator

2012 ◽  
Vol 463-464 ◽  
pp. 301-304 ◽  
Author(s):  
M. Ebrahimi ◽  
S.A. Jazayeri
Keyword(s):  
Inertia Force ◽  
Fluid Viscosity ◽  
Vane Pump ◽  
Pump Design ◽  
Inner Surface ◽  
Dynamics And Control ◽  
Internal Forces ◽  
Line Pressure ◽  
And Control ◽  
Selection Of

In the latest our works, Performance of a fixed displacement- hydraulic balance vane pump, theoretically and practically was studied by application of the basic hypertrochoid curve in the inner surface of its stator. Also the effect of the inertia force of the vanes on the performance of the pump with this curve was studied. This study presents a theoretical analysis of the internal pressure distribution in the pump, and of the resulting forces and torques applied to its components. This analysis is essential to the study of the pump dynamics and control, the pump design, and selection of the pump bearings. These forces are shown to be a function of the line pressure, the shaft rotational speed, the fluid bulk modulus, the fluid viscosity, and the design geometry. These forces are composed of two components: a continuous component due to the exposure of chambers to the line port, and an intermittent component due to a hydraulic lock phenomenon.

Esophageal sensation in spinal cord-injured patients: balloon distension and cerebral evoked potential recording

1996 ◽  
Vol 271 (6) ◽  
pp. G937-G941 ◽  
Author(s):  
K. R. DeVault ◽  
S. Beacham ◽  
D. O. Castell ◽  
L. J. Streletz ◽  
J. F. Ditunno
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Evoked Potential ◽  
Threshold Level ◽  
Sensory Function ◽  
Sensory Threshold ◽  
Balloon Distension ◽  
Cord Injury ◽  
Injured Patients ◽  
And Control

We sought to determine the esophageal sensory function in patients with a C6 or C7 spinal cord injury. A balloon was repetitively distended 10 cm above the lower esophageal sphincter in five patients and nine normal control subjects. Sensation was reported on a scale from 0 to 2 with progressive distension to pain threshold (level 2). Cortical responses were recorded from midline scalp electrodes. Blinded determinations of quality and reproducibility of the potentials were performed. All subjects experienced sensation with esophageal balloon distension. Volumes to sensation showed a trend toward a higher sensory threshold in patients but were significant only for first sensation, not pain. In all subjects, a triphasic evoked potential response consisting of a negative-positive-negative complex was noted with distension but not with sham distension. Characteristics (amplitude, latency, reproducibility, and quality) of the evoked potentials were not different in patient and control groups. These data suggest sensory pathways from the distal esophagus are intact in patients with a C6 or C7 spinal cord injury.

scholarly journals Molecular analysis of the cumulus matrix: insights from mice with O-glycan-deficient oocytes

Reproduction ◽  
2015 ◽  
Vol 149 (5) ◽  
pp. 533-543 ◽  
Author(s):  
Panayiota Ploutarchou ◽  
Pedro Melo ◽  
Anthony J Day ◽  
Caroline M Milner ◽  
Suzannah A Williams
Keyword(s):  
Cumulus Cells ◽  
Threshold Level ◽  
Oocyte Quality ◽  
Minimum Threshold ◽  
Cumulus Expansion ◽  
Heavy Chains ◽  
Essential Components ◽  
And Control ◽  
Specific Deletion

During follicle development, oocytes secrete factors that influence the development of granulosa and cumulus cells (CCs). In response to oocyte and somatic cell signals, CCs produce extracellular matrix (ECM) molecules resulting in cumulus expansion, which is essential for ovulation, fertilisation, and is predictive of oocyte quality. The cumulus ECM is largely made up of hyaluronan (HA), TNF-stimulated gene-6 (TSG-6, also known as TNFAIP6), pentraxin-3 (PTX3), and the heavy chains (HCs) of serum-derived inter-α-inhibitor proteins. In contrast to other in vivo models where modified expansion impairs fertility, the cumulus mass of C1galt1 Mutants, which have oocyte-specific deletion of core 1-derived O-glycans, is modified without impairing fertility. In this report, we used C1galt1 Mutant (C1galt1FF:ZP3Cre) and Control (C1galt1FF) mice to investigate how cumulus expansion is affected by oocyte-specific deletion of core 1-derived O-glycans without adversely affecting oocyte quality. Mutant cumulus–oocyte complexes (COCs) are smaller than Controls, with fewer CCs. Interestingly, the CCs in Mutant mice are functionally normal as each cell produced normal levels of the ECM molecules HA, TSG-6, and PTX3. However, HC levels were elevated in Mutant COCs. These data reveal that oocyte glycoproteins carrying core 1-derived O-glycans have a regulatory role in COC development. In addition, our study of Controls indicates that a functional COC can form provided all essential components are present above a minimum threshold level, and thus some variation in ECM composition does not adversely affect oocyte development, ovulation or fertilisation. These data have important implications for IVF and the use of cumulus expansion as a criterion for oocyte assessment.

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