Identification of Track Stability Model Parameters Based on Numerical Experiments

In the article, an identification method of railway track stability model parameters based on energy equilibrium is presented by the authors. A study of two parameters directly influencing the continuous welded track (CWR) stability is described by the authors, i.e., the rail-sleeper structure stiffness Bz is considered one beam, and the ballast lateral resistance r0. These parameters were estimated with the use of a numerical model for various railway track types. The adopted concept is based on the assumption that it is possible to determine substitute values for both parameters. Therefore, using one value of both of these parameters, we label them substitute parameters. The assumed numerical model forced lateral displacements of a track section, and, based on the obtained track section displacement results, energy equilibrium was determined. The equilibrium takes into account the work of external load and the bending work of rail-sleeper structure with the substitute stiffness Bz and the ballast deformation work, also with the substitute value of lateral resistance r0 with lateral displacement. The aim is to identify these substitute values to be used for analysing track stability with the semi-analytical model. These analyses are part of the studies related to the development of a method of assessing various methods of increasing track stability.

PROBLEMATIKA PERIKANAN PADA ZONA EKONOMI EKSKLUSIF INGGRIS DAN UNI EROPA

This research explains Brexit which leads to fisheries problems between United Kingdom (UK) and European Union (EU), regarding mechanism of methodology in distributing allocation of fishing quotas. This normative research uses statute, case, and comparative approach. The results shows that the problem between United Kingdom and European Union lies in the methodology of determining the amount of fishing quota through legal instruments established by the parties European Union wants to use relative stability model, whereas United Kingdom wants to use zonal attachment model Furthermore, the proposed form of solution that can be used in an effort to solve the fisheries problem between the United Kingdom and the European Union are thorugh one or more variation of zonal attachment, historical attachment, relative stability, or other mechanism (Hannesson Model).

Genetic Stability of TGMS Hybrids in Dry Direct Seeded Rice

Rice is a water-loving crop and traditionally sown in the nursery and then transplanted to the puddled and waterlogged main field. Owing to climate change, water scarcity and labour shortage problems, rice is now cultivated in the dry direct seeded method. Owing to potential of hybrid rice in increasing both rice production and productivity, many countries are focusing on exploiting the benefits of this technology. To break the yield plateau in rice cultivation, Thermosensitive Genetic Male Sterile (TGMS) hybrids were found to be very effective. In the present study, 41 TGMS hybrids and 9 checks were evaluated for their stability and adaptability by dry direct seeded method in four locations viz., E1 - Allahabad, E2 - Lucknow, E3 - Dhamtari and E4 - Raipur. The TGMS hybrid G44 was predicted as an ideal hybrid by the GGE stability model that possessed high grain yield and stable performance over environments. It was followed by hybrids viz., G10, G14, G34, G11, G20 and G47 that had a stable performance with high yield. Hence, these TGMS hybrids were identified as high and stable yielders across environments and suitable for dry direct seeded rice ecosystems. Among the environments, E1 (Allahabad) and E4 (Raipur) were considered favourable environments as they possessed the highest discriminating power. The hybrids identified in the study can be utilized for breaking the yield barriers in rice and can be recommended for dry direct seeding in marginal and rainfed areas.

Determinants of Political Stability to Support Foreign Investment in Indonesia

What investors often consider before deciding to invest in various countries is the political situation. The risks faced by investors in the event of political instability are regulatory changes, legal disputes, forced takeovers of companies, disruption to regional stability, policies against acts of terrorism, and changes in state ideology. The purpose of this study is to find a determinant of political stability in Indonesia that will be useful for investors and multinational companies, and the government in maintaining political stability. Systematic secondary data sampling from January 2015 to December 2019 was used for explanatory study purposes and to build a model. This study concludes that the rule of law, control of corruption, and oil prices have a significant effect on political stability in Indonesia, while the inflation rate does not have a significant effect on political stability in Indonesia. The novelty of this research is the formation of a political stability model for Indonesia and why an increase in control of corruption actually has a negative effect on political stability in Indonesia.

An Optical Acoustic Detection System Based on Fabry Pérot Etalon Stability Structure

The optical acoustic detection system based on the Fabry Pérot Etalon (FPE) with high quality–factor (High Q) and stability structure is described and tested. The FPE contains two high–reflectivity Plano–Concave lenses, achieving high fineness and stability. The protective structure of the confocal stabilized FPE is composed of an invar tube, copper sheath, Bakelite sheath and aluminum housing to protect the sensor from the effects of ambient temperature and vibration. The audio signal is injected into the cavity through the sound hole located in the center of the cavity. Acoustic waves induce the vibration of the medium in the cavity, which leads to a simultaneous change in the FPE optical path and a shift of the interference spectrum. The acoustic detection system is built, and the frequency of the laser is locked on the resonant frequency points of the FPE by using phase modulation technology, so as to detect acoustic signals of different frequencies and amplitudes. In addition, the sensitivity of the proposed sensor exceeds 34.49 mV/Pa in the range of 20 Hz–20 kHz. A Signal-to-Noise Ratio (SNR) of 37 dB can be achieved at 20 Hz. Acoustic signal detection technology based on the FPE stability model is used to test the theoretical feasibility of the future high sensitivity Fabry Pérot Interferometric (FPI) acoustic sensors.

AERODYNAMIC LIFT FORCES ON MULTIHULLED MARINE VEHICLES

The need for high-speed high-payload craft has led to considerable efforts within the marine transport industry towards a vehicle capable of bridging the gap between conventional ships and aircraft. One such concept uses the forward motion of the craft to create aerodynamic lift forces on a wing-like superstructure and hence, reduce the displacement and skin friction. This paper addresses the specific aerodynamic design of multihull for optimal lift production and shows that significant efficiency can be achieved through careful shaping of a ducted hull, with lift-to-drag ratios of nearly 50 for a complete aerodynamic hull configuration. Further analysis is carried out using a hybrid vehicle stability model to determine the effect of such aerodynamic alleviation on a theoretical planing hull. It is found that the resistance can be halved for a fifty metre, three hundred tonne vehicle with aerodynamic alleviation travelling at 70 knots. Results are presented for a candidate vessel.

Global Sensitivity Analysis of Groundwater Related Dike Stability under Extreme Loading Conditions

With up to 15% of the world’s population being protected by dikes from flooding, climate-change-induced river levels may dramatically increase the flood risk of these societies. Reliable assessments of dike stability will become increasingly important, but groundwater flow through dikes is often oversimplified due to limited understanding of the important process parameters. To improve the understanding of these parameters, we performed a global sensitivity analysis on a comprehensive hydro-stability model. The sensitivity analysis encompassed fifteen parameters related to geometry, drainage conditions and material properties. The following three sensitivity settings were selected to characterize model behavior: parameter prioritization, trend identification and interaction qualification. The first two showed that dike stability is mostly dependent on the dike slope, followed by the type of subsurface material. Interaction quantification indicated a very prominent interaction between the dike and subsurface material, as it influences both groundwater conditions and dike stability directly. Despite our relatively simple model setup, a database containing the results of the extensive Monte Carlo analysis succeeded in finding most of the unsafe sections identified by the official inspection results. This supports the applicability of our results and demonstrates that both geometry and subsurface parameters affect the groundwater conditions and dike stability.

Thermo-barometric constraints on the Mt. Etna 2015 eruptive event

The petrological study of volcanic products emitted during the paroxysmal events of December 2015 from the summit craters of Mount Etna allow us to constrain T-P-XH2O phase stability, crystallization conditions, and mixing processes along the main open-conduit feeding system. In this study, we discuss new geochemical, thermo-barometric data and related Rhyolite-MELTS modelling of the eruptive activity that involved the concomitant activation of all summit craters. The results, in comparison with the previous paroxysmal events of the 2011–2012, reinforce the model of a vertically extended feeding system and highlight that the activity at the New South-East Crater was fed by magma residing at a significantly shallower depth with respect to the Central Craters (CC) and North-East Crater (NEC), even if all conduits were fed by a common deep (P = 530–440 MPa) basic magmatic input. Plagioclase dissolution, resorption textures, and the Rhyolite-MELTS stability model corroborate its dependence on H2O content; thus, suggesting that further studies on the effect that flushing from fluids with different H2O/CO2 ratio are needed to understand the eruption-triggering mechanisms for high energetic strombolian paroxysmal episodes.