Seismic Imaging of the Upper Mantle under the Erebus Hotspot in Antarctica

P-wave velocity images are determined under the Mount Erebus hotspot,Antarctica by using teleseismic tomography.Our results show a prominent low-velocity(low-v)anomaly of nearly circular symmetry(about 250-300 km in diameter)to about 200 km depth under the Mount Erebus volcanic region,which further extends down to～400 km as a narrow tilted column.The observed low-v anomaly beneath the Mount Erebus volcano can be an expression of a thermal anomaly of deep origin.

PAPR Reduction of NOMA Using Vandermonde Matrix-Particle Transmission Sequence

Non-Orthogonal Multiple Access(NOMA)is an ideal choice for 5G waveforms due to their characteristics such as high data rate,massive device connectivity,high spectral access,and effective frequency selective fading.Thus,it permits gigantic connectivity.The spectrum overlaps with NOMA,which consents several operators to segment the spectrum at the same frequency.These features make NOMA more suitable for use beyond 5G.Peak to Average Power(PAPR)is a major problem in Multi-Carrier Techniques(MCT)like NOMA and it also degrades the performance of the amplifier.The Partial Transmission Sequence(PTS)is a superior algorithm for moderating the PAPR.However,it also increases the complexity of the structure.The PAPR is reduced in NOMA by multiplying the NOMA signal with optimised phase vectors(P).The phase vectors are generated by using the Vandermonde Matrix(VM).In this work,we proposed a VM-PTS algorithm for the NOMA system,and the number of computations to search the optimal phase vectors for NOMA high PAPR signal is less as compared with existing PTS.The outcomes demonstrate that the performance of the recommended PTS in terms of PAPR,Bit Error Rate(BER),and complexity is better than the conventional PTS(C-PTS).

Crustal Tomography Under the Median Tectonic Line in Southwest Japan Using P and PmP data

The Median Tectonic Line(MTL)is the largest active fault system on the Japan Islands and underlies many densely populated areas.To understand the seismotectonics and to reduce seismic hazard in the MTL region,we determined a detailed 3-D crustal structure under the region using a large number of arrival times of the first P-waves and Moho-reflected waves(PmP).Results of detailed resolution tests show that the addition of PmP data can significantly improve the resolution of the lower crustal structure and the entire crustal structure can be imaged better than that by using P-wave data alone.The

Formation and Evolution of Dharwar Craton in South India-Synthesis from Broadband Seismological Experiment

Understanding the structure,composition and survival of Archaean cratons over geological times is critical to model the process of crustal evolution.The South India Broadband Seismic Imaging Experiment was organized to answer fundamental questions of craton formation,with the principal objective of characterizing physico-chemical nature of the crust and mantle of Dharwar craton and adjoining terrains.

Development of Diagnostics for High-Temperature High-Pressure Liquid Pb-16Li Applications

Liquid lead-lithium (Pb-16Li) is of primary interest as one of the candidate materials for tritium breeder, neutron multiplier and coolant fluid in liquid metal blanket concepts relevant to fusion power plants. For an effective and reliable operation of such high temperature liquid metal systems, monitoring and control of critical process parameters is essential. However, limited operational experience coupled with high temperature operating conditions and corrosive nature of Pb-16Li severely limited application of commercially available diagnostic tools. This paper illustrates indigenous calibration test facility designs and experimental methods used to develop non-contact configuration level diagnostics using pulse radar level sensor, wetted configuration pressure diagnostics using diaphragm seal type pressure sensor and bulk temperature diagnostics with temperature profiling for high temperature, high pressure liquid Pb and Pb-16Li applications. Calibration check of these sensors was performed using analytical methods, at temperature between 380°C - 400°C and pressure upto 1 MPa (g). Reliability and performance validation were achieved through long duration testing of sensors in liquid Pb and liquid Pb-16Li environment for over 1000 hour. Estimated deviation for radar level sensor lies within [−3.36 mm, +13.64 mm] and the estimated error for pressure sensor lies within 1.1% of calibrated span over the entire test duration. Results obtained and critical observations from these tests are presented in this paper.

Impact of binary blends of biodiesels on fuel quality,engine performance and emission characteristics

The incessant pressure of energy requirements by the growing global populace has led to the exploration of unconventional methods to produce renewable and sustainable fuels.Among these,biodiesel is most suited to the present needs of eco-friendly standards to keep the atmosphere free from residual emissions.Various fuel-modification methods were developed over a couple of decades to make biodiesel suitable for diesel engines.In the present research,Jatropha curcas biodiesel and waste-cooking-oil(WCO)biodiesel were used to craft a unique binary blend to obtain desirable fuel properties and operational suitability for the diesel engine.The blend with 80% WCO biodiesel and 20% J.curcas biodiesel,which had the most suitable fuel properties,was tested on a four-stroke single-cylinder vertical diesel engine.The emissions and operational parameters were analysed and compared with diesel.The results of the study indicated that engine emissions for binary blend,carbon monoxide and unburnt hydrocarbon emissions were highly reduced,and carbon dioxide and nitrogen oxide(NO_(x))emissions increased relative to diesel.At full load,NO_(x) emission was found to be 51.32% higher than that from diesel and 3.8% lower than that from WCO biodiesel.Engine performance showed that for the binary blend,at full load,the brake-specific fuel consumption was 396.82 g/kWh,which was 15.26% higher,and the brake thermal efficiency was 22.7%,which was 2.74% lower than regular diesel fuel.The present study suggests that the binary blend of J.curcas biodiesel and WCO biodiesel can be a promising approach towards advancements in the fuel properties of biodiesels.

The role of trochanteric flip osteotomy in fixation of certain acetabular fractures

Purpose： Complete visualization of certain acetabular fractures of posterior wall or column with cranial extension involving superior dome from standard surgical exposures is a challenge. Osteotomy of the greater trochanter has been used to enhance fracture visualization, especially the dome, in posterior and lateral exposures of the acetabulum, it also decreases the need for excessive muscle retraction. The purpose of the study was to investigate the outcome associated with trochanteric flip osteotomy in the management of certain acetahulum fractures. Methods： From January 2011 to December 2013, 25 displaced acetabular fractures were treated by open reduction and internal fixation. The fractures were managed using a Kocher-Langenbeck approach along with trochanteric flip osteotomy. At 3rd, 6th and 24th month follow-up, all patients had radiographic examination and underwent a final clinical evaluation based on the modified Merle d＇Auhigne and Postei score. The strength of the abductors was assessed according to the Medical Research Council （MRC） grading system. Results： Congruent reduction was achieved in all patients and all osteotomies healed within an average period of 3.8 months. All our patients were allowed full weight bearing at the end of 3 months and with no abductor lurch at the end of 6 months follow-up. There were no cases of avascular necrosis of femoral head. None of the patients had any neurovascular complication or infection by the end of the follow-up period. Conclusion： Truchanteric flip osteotomy is a very effective technique to fix certain acetabular fractures especially those with dome involvement. It is more accurate and associated with no significant com- plications compared with conventional way.

Use of tricortical iliac crest strut autograft in comminuted posterior wall acetabular fractures： A case series

Purpose： The results for fixation of comminuted posterior wall acetabular fractures are not very promising with reported complications in terms of osteoarthritis, nonunion and malunion which subsequently require conversion to total hip arthroplasty. The conversion to total hip arthroplasty is possible in patients over 50 years of age but not in younger patients. So this requires new methods for salvage of the native hip in young patients. Methods： There were six patients in our series with highly comminuted posterior wall acetabular frac- tures where the fragments were excised and the gap filled with tricortical anterior iliac-crest strut autograff, fixed with screws and plate. Results： Good results were achieved in four out of six patients analyzed clinically using the Merle d＇Aubinge score modified by Matta and radiologically by Matta scoring. These patients have returned to original work and are walking independently. The good result in one patient deteriorated from good to poor between one and two years. One patient developed infection and excision arthroplasty was done, The graft incorporated well in five out of six patients. Conclusion： The use of iliac crest autograff is a better, advanced and promising technique as it provides a new wall to the weight bearing dome of the acetabulum for articulation with the femoral head. The rates of nonunion, malunion, post traumatic osteoarthritis are less as compared to the fixation of the comminuted fragments. The need for conversion to total hio arthroolastv is also less.