Search results for "loop"
showing 10 items of 608 documents
Electroweak measurements in electron-positron collisions at W-boson-pair energies at LEP
2013
The ALEPH, DELPHI, L3, OPAL collaborations and LEP Electroweak Working Group.-- arXiv:1302.3415
A self-synchronizing instrument for harmonic sources detection in power systems
2004
The deregulation of energy markets holds out new prospects for contract between customers and utilities, in which the price of energy can depend on voltage quality and load characteristics, as well as on the responsibility for disturbances caused to supply voltage in power systems. In this context, harmonic sources detection is one of the main problems, because of equipment sensibility and the proliferation of loads which absorb non-sinusoidal currents. In this paper the authors present a new instrument based on a time domain method for the detection of harmonic active powers in three-phase systems, which can be usefully applied even in the presence of unbalance or asymmetry. The amplitude …
A time domain strategy for the measurement of IEEE Standard 1459-2000 power quantities in nonsinusoidal three-phase and single-phase systems
2008
This paper describes a time domain technique for the detection of fundamental and harmonic components of voltages and currents, which is able to evaluate all the quantities required by IEEE standard 1459-2000. The technique does not require any spectral analysis to separate the fundamental positive-sequence components from harmonic, negative-sequence and zero-sequence ones. In the paper the development of the proposed technique is presented for three-phase systems, both three-wires and four-wires, as well as for single-phase systems. The implementation of the proposed technique on a PC-based instrument is also described and experimental results are presented. Finally, accuracy specification…
Transcriptional regulation of the stem cell leukemia gene by PU.1 and Elf-1.
1998
Abstract The SCL gene, also known astal-1, encodes a basic helix-loop-helix transcription factor that is pivotal for the normal development of all hematopoietic lineages. SCL is expressed in committed erythroid, mast, and megakaryocytic cells as well as in hematopoietic stem cells. Nothing is known about the regulation of SCL transcription in mast cells, and in other lineages GATA-1 is the only tissue-specific transcription factor recognized to regulate the SCL gene. We have therefore analyzed the molecular mechanisms underlyingSCL expression in mast cells. In this paper, we demonstrate that SCL promoter 1a was regulated by GATA-1 together with Sp1 and Sp3 in a manner similar to the situati…
Transcriptional Mechanisms of Proneural Factors and REST in Regulating Neuronal Reprogramming of Astrocytes
2015
Summary Direct lineage reprogramming induces dramatic shifts in cellular identity, employing poorly understood mechanisms. Recently, we demonstrated that expression of Neurog2 or Ascl1 in postnatal mouse astrocytes generates glutamatergic or GABAergic neurons. Here, we take advantage of this model to study dynamics of neuronal cell fate acquisition at the transcriptional level. We found that Neurog2 and Ascl1 rapidly elicited distinct neurogenic programs with only a small subset of shared target genes. Within this subset, only NeuroD4 could by itself induce neuronal reprogramming in both mouse and human astrocytes, while co-expression with Insm1 was required for glutamatergic maturation. Cu…
Recruitment of HIF-1α and HIF-2α to common target genes is differentially regulated in neuroblastoma: HIF-2α promotes an aggressive phenotype
2006
In neuroblastoma specimens, HIF-2alpha but not HIF-1alpha is strongly expressed in well-vascularized areas. In vitro, HIF-2alpha protein was stabilized at 5% O2 (resembling end capillary oxygen conditions) and, in contrast to the low HIF-1alpha activity at this oxygen level, actively transcribed genes like VEGF. Under hypoxia (1% O2), HIF-1alpha was transiently stabilized and primarily mediated acute responses, whereas HIF-2alpha protein gradually accumulated and governed prolonged hypoxic gene activation. Knockdown of HIF-2alpha reduced growth of neuroblastoma tumors in athymic mice. Furthermore, high HIF-2alpha protein levels were correlated with advanced clinical stage and high VEGF expr…
A Cost-Effective Approach to Hardware-in-the-Loop Simulation
2012
This paper presents an approach for developing cost effective hardware-in-the-loop (HIL) simulation platforms for the use in controller software test and development. The approach is aimed at the many smaller manufacturers of e.g. mobile hydraulic machinery, which often do not have very advanced testing facilities at their disposal. A case study is presented where a HIL simulation platform is developed for the controller of a truck mounted loader crane. The total expenses in hardware and software is less than 10.000$.
Radiometric Partial Discharge Detection: A Review
2023
One of the most common failures or breakdowns that can occur in high-voltage (HV) equipment is due to partial discharges (PDs). This occurs as a result of inadequate insulation, aging, harsh environmental effects, or manufacturing flaws. PD detection and recognition methods have gained growing attention and have seen great progress in the past decades. Radiometric methods are one of the most investigated detection approaches due to their immunity to electromagnetic interference (EMI) and their capabilities to detect and locate PD activities in different applications such as transformers, cables, etc. Several review articles have been published to classify and categorize these works. Nonethe…
Development, modeling and simulation of test equipment for subsea choke valves
2014
Masteroppgave i mekatronikk MAS 500 Universitetet i Agder 2014 As a step toward being more e_ective and to improve test procedures, GE Oil & Gas wants to develop a workshoptool to automate the testing of Choke Valves. The Choke Valve Workshop Tool (CVWT) main functionis to operate the Hydraulic Stepping Actuator automatically by providing controlled pressure pulses. Electricaland hydraulic equipment will have an interface allowing the test equipment to be connected and used on awide range of Choke Valves. Test results will be transferred and stored automatically based on current need. Adetailed description of the planned CVWT including a complete control system and a Human Machine Interface…
Atgriezto preču apstrādes procedūras pilnveidošana uzņēmumā X
2016
Uzņēmums X Latvijā ir ieviesis līdz šim nebijušu E-komercijas veidu- jaunu un mazlietotu preču noma interneta vidē. Pakalpojums pats par sevi šķiet līdzīgs līzingam vai kredītam, taču pakalpojuma galvenā atšķirība ir tā, ka ir iespēja jebkurā brīdī atgriezt preci, kad tā nav vairs vajadzīga, līdz ar to ir iespējams lauzt līgumu un pārtraukt līgumsaistības. Diplomdarba mērķis ir izpētīt uzņēmuma pašreizējo atgriezto preču apstrādes procesu, identificēt tā darbībā iesaistīto procedūru trūkumus un uzlabošanas iespējas. Veikt atgriezto preču apstrādes procesa pilnveidošanu, izmantojot uzdevumu pārvaldības sistēmu, uzlabot, kā arī izstrādāt jaunas procedūras, kas uzlabotu un atvieglotu uzņēmuma …