Unleashing the full power of LHCb to probe Stealth New Physics

In this paper, we describe the potential of the LHCb experiment to detect Stealth physics. This refers to dynamics beyond the Standard Model that would elude searches that focus on energetic objects or precision measurements of known processes. Stealth signatures include long-lived particles and light resonances that are produced very rarely or together with overwhelming backgrounds. We will discuss why LHCb is equipped to discover this kind of physics at the Large Hadron Collider and provide examples of well-motivated theoretical models that can be probed with great detail at the experiment.

Forensic Linguistics : Problems in Conducting Linguistic Examinations

In the modern world, the issues of countering extremism are becoming more Vital and urgent, the most dangerous form of which is flourishing terrorism, which has become a global threat as can be judged from the data of public opinion polls, if ten years ago the fight against terrorism was not considered an important component to an ordinary citizen. Skillful politicians, orators are well aware of the full power of the influence of the word. This power is often used for selfish purposes. To identify signs of speech offenses, to effectively combat them, cohesive and organized actions of law enforcement agencies and courts are needed. Besides, the most important stage in this struggle is the actual detection of the “extremist infection”, which strikes such a delicate sphere of social relations in itself”. So, just, for example, let us note that national and racial hostility is acquiring increasing importance in society. The idea of religious exclusivity, implying the predominance of one group over another due to the imperfection of the latter, encourages aggressive people to various appeals, appeals, teachings, and threats. All these actions are aimed at disseminating negative information, are aimed at involving more and more new supporters in the ranks of the aggressors, therefore, they must be strictly suppressed . One of the features of the propaganda described above is that it is carried out with the help of the media. And quite often the very fact of a speech violation, visible, as it seems, with the naked eye, upon closer and detailed examination, causes a lot of bewilderment and controversy. Meanwhile, to detect an offense and crime, to pass a sentence, the court must be not only sure of the existence of a crime but also be aware of the extent of its danger to society. That is why practically all-important cases on the problems of extremism, racial, national hostility are considered with the obligatory involvement of linguistic experts.

Some results of voltage increase in marine electrical propulsion installations

The main voltage parameters of marine electrical propulsion installations, at various load capacities, with further stress assessment are discussed in the article. By considering voltage options, it was revealed that an increase in inductive resistance makes it possible to manufacture a machine with high power, but the quality of electrical energy in transient modes is deteriorated. During starts, reversals, resets and load surges of powerful consumers, large voltage dips will occur on the generator. To solve the problem, including determination of optimal parameters of the generator, based on the multifactorial nature of the task of creating an electric machine for a specific purpose, an analysis of all the necessary parameters was carried out. The main dimensions of the machine depend on its full power, angular speed and electromagnetic loads. The article presents technical solutions considered using the example of a modern multipurpose icebreaker-supply “Vitus Bering”. Also, as an example, an icebreaker of the Taimyr type with a limited draft is considered, for the first time in modern practice, an alternating-changing current EDMS is used. From the experience of operating the icebreakers “Taimyr” and “Vaigach”, the transition to high voltage did not lead to a complication and increase in the complexity of the maintenance of the MPM, although it required strict compliance with safety regulations during the work. During the operation of icebreakers with MPM 6.3 kV, not a single case of single-phase short circuit or electrical injury has been recorded.

Double Heterogeneity Neutronic Simulation of HTR-10 for First Criticality and Full Power Initial Core with TORT-TD code

In order to support the verification and validation of computational methods and codes for the safety assessment of pebble bed High-Temperature Gas-cooled Reactors (HTGRs), the calculation of first criticality and full power initial core of the high-temperature pebble bed reactor 10 MWt (HTR-10) has been defined as one of the problems specified for both code-to-code and code-to-experiment benchmarking with a focus on neutronics. HTR-10 Experimental facility serves as the source of information for the currently designed high-temperature gas-cooled nuclear reactor. It is also desired to verify the existing codes against the data obtained in the facility. In HTR-10, the core is filled with thousands of graphite and fuel pebbles. Fuel pebbles in the reactor consist of TRISO particles, which are embedded in the graphite matrix stochastically. The reactor core is also stochastically filled with pebbles. These two stochastic geometries comprise the so-called double heterogeneity of this type of reactor. In this paper, the first criticality and the power distribution in full power initial core calculations of HTR-10 are used to demonstrate treatment of this double heterogeneity using TORT-TD and Serpent for cross-section generation. HTR-10 has unique characteristics in terms of the randomness in geometry, as in all pebble bed reactors. In this technique, the core structure is modeled by TORT-TD, and Serpent is used to provide the cross-section in a double heterogeneity approach. Results obtained by TORT-TD calculations are compared with available data. It is observed that TORT-TD calculation yield sufficiently accurate results in terms of initial criticality and power distribution in full power initial core of the HTR-10 reactor.

Electromechanical Transient Modeling and LVRT Parameter Identification of Large Capacity Full Power Converter Wind Turbines Based on PSASP Program

Full power converter wind turbine is the main type of wind power, so the simulation calculation needs to establish accurate model parameters. This paper analyzes the model structure of PSASP program according to its low voltage ride through control and physical characteristics, and puts forward the parameter identification method of LVRT characteristics of full power converter wind turbine, and to use the LVRT data of 5. 5MW unit for parameter identification and simulation verification. This paper proposes that the electromechanical transient simulation can ignore the part of the generator model of the full power converter wind turbine, and simulates the grid side converter with the controlled current source. The main characteristics of LVRT are determined by the control system of the converter. In order to do the parameter identification, it is necessary to calculate and analyze the control characteristics of multiple measured data. First, determine the control mode, then determine the control parameters to complete the parameter identification. In this paper, the modeling conditions and model structure of the full power converter wind turbine are confirmed. The correlation between the parameters during the LVRT fault and the parameters during the LVRT recovery period and the LVRT characteristics is analyzed. In this paper, a parameter identification method is proposed to analyze the active current and reactive current during the LVRT fault, which has strong physical significance and operability. Based on the actual LVRT characteristics of 5. 5MW wind turbine, the parameter identification and simulation are carried out to verify the correctness of the method.

Multicell Power Supplies for Improved Energy Efficiency in the Information and Communications Technology Infrastructures

The rapid growth of the Information and Communications Technology (ICT) sector requires additional infrastructure, such as more micro-datacenters and telecom stations, to support the higher internet speeds and low latency requirements of 5G networks. The increased power requirements of the new ICT technologies necessitate the proposal of new power supplies, in an attempt to support the increase in energy demand and running costs. This work provides an in-depth theoretical analysis on the losses of the individual stages of commercially available PSU and proposes a new multicell PSU, the buck PFC converter, which offers a higher overall efficiency at varying load levels. The theoretical results are verified using simulation results, via a PSIM Thermal Module, and using experimental data. The results indicate that multicell structures can improve the overall PSU efficiency by 1.2% at 50% rated power and more than 2.1% at full power. Finally, taking into consideration the economic implications of this study, it is shown that the proposed multicell structure may increase the PSU costs by 10.78%, but the payback period is in the order of just 3.3 years.

Die-Level Vacuum Packaging of Mems Devices with Non-Evaporating Getters

In this article original method of vacuum packaging in ceramic package 5142.48-A with non-evaporating getter inside is described. Some MEMS devices such as gyroscopes, accelerometers and resonators often require high and stable vacuum for operational capability. It is known two main approaches to the vacuum packaging of MEMS devices: hermetization on the wafer level and on the die level. Die-level vacuum packaging can be implemented by sealing the die in ceramic package providing excellent hermeticity with sufficiently low leak rate. However, because of outgassing from materials of the package it is difficult to achieve stable vacuum over all MEMS device lifetime. To prevent vacuum degradation it is necessary to use special materials that can remove active gases from the package by chemical sorption named getters. In this work tablet-shaped non-evaporating getter with thickness of 0.7 mm made of titan-vanadium alloy with activation temperature near 525 °C was used. For the vacuum packaging workflow new special vacuum chamber is designed. It may contain four MEMS devices simultaneously. During the process of getter activation heating was provided by halogen lamps G12 35 Wplaced over the caps of the ceramic packages with a little gap. It is defined that in deep vacuum full power of one lamp can heat the cap of the package to the temperature more than 600 °C. Probable overheating is excluded by means of the newly-designed programmable device — power switch, which can maintain required temperature in automatic mode for the necessary time. Temperature control is realized by no-contact pyrometrical method. During the experiment all necessary parameters providing specified temperature profile of the process were determined. Efficiency of the developed vacuum packaging workflow is successfully confirmed by the high and stable Q-factor of fabricated MEMS gyroscopes.

Modeling Hybrid Hydro-Electro-Mechanical Power-Split Propulsion Systems

Hydrostatic and hydro-mechanical transmissions (HSTs and HMTs, respectively) are commonly used in off-highway vehicles. While both transmission technologies can provide continuously variable torque or speed ratios, they suffer from poor efficiencies and limited operating ranges. Electric variable transmissions (EVTs), in contrast, offer complementary strengths via higher efficiencies at low forward and reverse speeds, full torque from zero to full power, and increased control capabilities. While HST, HMT, and EVT powertrain architectures are not novel, the authors are not aware of work integrating these technologies into hydro-electro-mechanical (HEMT) transmission architectures. Thus, this research aimed to develop a physical modeling methodology to explore different power-split transmission technologies using hydraulic, electrical, and mechanical pathways to understand how the complementary nature of the technologies could be used for overall power transmission performance. Steady-state modeling was performed using the Modelica® (Modelica Association) modeling language in the Dymola (Dassault Systems®) integrated development environment. Overall efficiency vs. output speed was presented for HMT, EMT, and HEMT input-coupled architectures, including circulating power considerations. This research extends the state-of-the-art of off-road powertrain technologies by providing the literature an exemplar modeling of HEMT coupling techniques, system integration, and power flow architectures in Modelica® modeling language.