Showing papers by "Mobil published in 2010"

Planning Problems in Public Transit

Abstract: Every day, millions of people are transported by buses, trains, and airplanes in Germany. Public transit (PT) is of major importance for the quality of life of individuals as well as the productivity of entire regions. Quality and efficiency of PT systems depend on the political framework (state-run, market oriented) and the suitability of the infrastructure (railway tracks, airport locations), the existing level of service (timetable, flight schedule), the use of adequate technologies (information, control, and booking systems), and the best possible deployment of equipment and resources (energy, vehicles, crews). The decision, planning, and optimization problems arising in this context are often gigantic and “scream” for mathematical support because of their complexity.

Structural and stratigraphic relationships of the Palaeocene mounds of the Utsira High

Abstract: The Balder and Ringhorne Tertiary oilfields of the Utsira High are a cluster of prominent Palaeocene mounds, whose presence has confounded geologists since they were first observed on 2D seismic data back in the 1960s and 1970s. Until recently, the Balder Field geologic model consisted of distal, deep-water Heimdal, Hermod and Balder Formation sandy-debrite and turbidite sands, compensationally stacked along the flanks of the Utsira palaeo-high, with intervening layers of hemipelagic shale. Remobilization of the sands by large- scale fluidization accentuated the high relief mounds and sand injections linked reservoirs that were originally isolated. Reprocessed seismic data show strong primary reflectors that cannot be reconciled with this model; continuous sand bodies are observed to cross-cut normal, biostratigraphically constrained sequence-stratigraphic reflectors.The implication is that many, if not most, of the Hermod and Balder sands are not depositional, but were emplaced by injection. Furthermore, most of the Palaeocene mounds are associated with major \\\\\\\'tears\\\\\\\' in the normally smooth Top Cretaceous chalk seismic reflector, and overlying chalk \\\\\\\'rafts\\\\\\\'. The chalk rafts were formerly thought to be detached glide-blocks, shed from distant scarps to the east, but the improved data show that they are always positioned above matching depressions in the main Chalk, implying a local origin. Some of the rafts are immense, exceeding half a kilometre in width and millions of tonnes in mass. We believe the association of the chalk features with the mounds is more than a coincidence and suggest that they are genetically related. A number of driving mechanisms have been proposed for the formation of the Palaeocene mounds of the Utsira High, including normal post-depositional compaction, fluidization by earthquakes, overpressuring due to gas migration and gravity-sliding back into the Viking Graben. Our observations are, however, more consistent with the mounds resulting from episodic supra-lithostatic pressure escape from beneath the Chalk.

Ethylene polymerization reactions with multicenter Ziegler‐Natta catalysts—Manipulation of active center distribution

Abstract: This article describes ethylene/1-hexene copolymer- ization reactions with a supported titanium-based, multicenter Ziegler-Natta catalyst. The catalyst was modified by pretreating its solid precursor with AlEt2Cl and with similar organoaluminum chlorides, Al2Et3Cl3, AlEtCl2 ,a nd AlMe 2Cl. Testing of the un- treated and the pretreated catalysts in copolymerization reactions under standard reaction conditions demonstrated that the modi- fying agents produce two changes in the catalyst. First, the pre- treatment significantly reduces the reactivity of active centers that produce high molecular weight, highly crystalline copolymer components with a low 1-hexene content. Second, the pretreat- ment noticeably increases the reactivity of active centers that produce low molecular weight copolymer components with a high 1-hexene content. The first effect is caused by Lewis acid- base interactions of the modifiers with the active centers, whereas the second (activating) effect is due to the removal of catalyst poisons (organosilicon compounds generated in the pro- cess of the catalyst synthesis) by AlEt2Cl. V C 2010 Wiley Periodi- cals, Inc. J Polym Sci Part A: Polym Chem 48: 4219-4229, 2010

IP–Multimedia Subsystem (IMS) performance evaluation and benchmarking

Abstract: Evaluating the IP Multimedia Subsystem (IMS) Performance is very important due to the critical role it plays in the Next Generation Network (NGN) of the Fixed and Mobile Networks. This paper proposes three robust and scalable methods that can be used to evaluate the performance, the Compliance of the IMS controllers and benchmark their different vendors. These methods are, Performance Test, FUZZING Test and the test using Spectra 2|SE tool. These issues are studied experimentally, using Open SIP Express Router (OpenSER), a high performance open source SIP server and SIPp, the de-facto standard for SIP performance benchmarking. It also provides the test results for Open SIP Express Router (OpenSER).

A simplified training pattern for MIMO-OFDM channel estimation technology

Abstract: The tracking of fading wireless channel is needed in MIMO-OFDM system. Training sequences can be used for synchronization and channel estimation. However, if too much training blocks are used, the efficiency of system will be decreased. A simplified training pattern which can reduce the waste of resources is proposed in this paper. Computer simulations prove that performance of the system with simplified pattern is almost equivalent to the system doesn't use the simplified training pattern under low SNR, with SNR rising, the performance of the system with simplified training block pattern will become better and better, and the simplified pattern can save four OFDM periods for transmitting training blocks.

Lowdin Transform on FCC Optimized UWB Pulses

Abstract: In this contribution we present a novel method for constructing orthogonal pulses for UWB impulse radio transmission under the FCC spectral mask constraint. In contrast to previous work we combine a convex formulation of the spectral design with Lowdin's orthogonalization method [1], which delivers a shift--orthogonal basis optimally close (in energy) to the initial pulse, which generates (in a stable way) the shift--invariant space. The convex formulation of the spectral design is achieved by approximating the FCC mask with a finite--order filter matched to Gaussian monocycles as input. The output pulse then has high energy concentration in the passband (NESP value). Using Lowdin's orthogonalization we compute the corresponding shift--orthogonal pulse. We show that our approach is able to generate for finitely many shifts, orthogonal equal energy pulses with nearly the same NESP value. Furthermore, we show that the orthogonalization procedure can be well approximated using the Zak transform allowing for an efficient implementation with the discrete Fourier transform. Surprisingly, we could observe, that for certain parameters, this approximation yields almost the same performance as the exact Lowdin method.

One-error-proof path or angular sensor unit for electrohydraulic steering system for road vehicle, has processing units including control unit for target size determination for controlling actuator and/or for triggering fail-safe-reaction

Abstract: The sensor unit (200) has sensors for path and angle detection, processing units, and power outputs (40) controlling an electrohydraulic actuator (500). The processing units include a control unit for target size determination based on determined sensor measurement values for controlling the actuator and/or for triggering a fail-safe-reaction. The processing units are connected with each other for mutual data exchange over an internal connection. A sensing unit generates an output signal for controlling the power outputs, which is proportional to angular speed in velocity and direction. An independent claim is also included for a steering system comprising am axle unit.

Method for changing a dynamic steering program

Abstract: The method involves providing a continuous transition between steering programs for driving and steering a vehicle during a steering program change. The steering program change is performed by dynamic and continuous movement of steering poles (7) of steered wheels (5). The steering program change is covered from longitudinal drive to transverse drive or from the transverse drive to the longitudinal drive including movement processes that take place by rotation of the steering poles. Dynamic steering program change is executed between longitudinal and transverse programs.

Drive over bulkweigher transload system

Abstract: A system and method for weighing and loading particulate material while the particulate material is passing through the system is provided. The system can include a roadway, an opening positioned in the roadway and at least one bulkweigher provided below the opening. A rail car or a trailer can be positioned above the opening in the roadway and particulate material discharged from the rail car or trailer through the opening into the at least one bulkweigher. The bulkweigher can weigh the particulate material as it is being discharged and, after the particulate material has been weighed by the at least one bulkweigher, the bulkweigher can discharge the particulate material onto a conveyor to be loaded into another rail car or trailer.