Intelligent Multi-Vehicle DC/DC Charging Station Powered by a Trolley Bus Catenary Grid

This article deals with the major challenge of electric vehicle charging infrastructure in urban areas—installing as many fast charging stations as necessary and using them as efficiently as possible, while considering grid level power limitations. A smart fast charging station with four vehicle access points and an intelligent load management algorithm based on the combined charging system interface is presented. The shortcomings of present implementations of the combined charging system communication protocol are identified and discussed. Practical experiments and simulations of different charging scenarios validate the concept and show that the concept can increase the utilization time and the supplied energy by a factor of 2.4 compared to typical charging station installations.

Performance efficiency of virtual laboratory based on Unity 3D and Blender during the Covid-19 pandemic

Testing the performance efficiency aspect was carried out to test the performance efficiency of the Unity 3D and Blender-based virtual laboratory media during the COVID-19 pandemic at the Electrical Engineering Vocational Laboratory. This test is carried out to test the performance of the media that has been created. The aspects tested are access speed, process speed, and simulation speed when run. Tests were conducted to measure processor and memory consumption through real time monitoring using MSI Afterburner. Divided into 2 stages of testing, namely time behavior and resource utilization. Time-behavior is focused on how long it takes the media or software to provide a response time to perform an action from a certain function. Resource-utilization is the degree to which software uses some resources when doing something under certain conditions.

The META tool optimizes metagenomic analyses across sequencing platforms and classifiers.

A major challenge in the field of metagenomics is the selection of the correct combination of sequencing platform and downstream metagenomic analysis algorithm, or classifier. Here, we present the Metagenomic Evaluation Tool Analyzer (META), which produces simulated data and facilitates platform and algorithm selection for any given metagenomic use case. META-generated in silico read data are modular, scalable, and reflect user-defined community profiles, while the downstream analysis is done using a variety of metagenomic classifiers. Reported results include information on resource utilization, time-to-answer, and performance. Real-world data can also be analyzed using selected classifiers and results benchmarked against simulations. To test the utility of the META software, simulated data was compared to real-world viral and bacterial metagenomic samples run on four different sequencers and analyzed using 12 metagenomic classifiers. Lastly, we introduce META Score: a unified, quantitative value which rates an analytic classifiers' ability to both identify and count taxa in a representative sample.

Extended performance accounting using Valgrind tool

Modern workloads, parallel or sequential, usually suffer from insufficient memory and computing performance. Common trends to improve workload performance include the utilizations of complex functional units or coprocessors, which are able not only to provide accelerated computations but also independently fetch data from memory generating complex address patterns, with or without support of control flow operations. Such coprocessors usually are not adopted by optimizing compilers and should be utilized by special application interfaces by hand. On the other hand, memory bottlenecks may be avoided with proper use of processor prefetch capabilities which load necessary data ahead of actual utilization time, and the prefetch is also adopted only for simple cases making programmers to do it usually by hand. As workloads are fast migrating to embedded applications a problem raises how to utilize all hardware capabilities for speeding up workload at moderate efforts. This requires precise analysis of memory access patterns at program run time and marking hot spots where the vast amount of memory accesses is issued. Precise memory access model can be analyzed via simulators, for example Valgrind, which is capable to run really big workload, for example neural network inference in reasonable time. But simulators and hardware performance analyzers fail to separate the full amount of memory references and cache misses per particular modules as it requires the analysis of program call graph. We are extending Valgrind tool cache simulator, which allows to account memory accesses per software modules and render realistic distribution of hot spot in a program. Additionally the analysis of address sequences in the simulator allows to recover array access patterns and propose effective prefetching schemes. Motivating samples are provided to illustrate the use of Valgrind tool.

Successful Hydraulic Isolation Assessment Saves Rig Utilization Time and Unnecessary Cement Remedial Squeeze Operation - Case Study, Kuwait

While drilling an 8 1/2-incli section of a north Kuwait producer well, severe mud losses were encountered. Hence, it was decided to design a light weight cement for the 7-inch liner section to avoid further losses while pumping the slurry. The main objective was to achieve a hydraulic isolation to avoid any heavy remedial intervention and potential dump flood behind the liner from the high-pressure Lower Burgan (LB) to Shuaiba. Full suite of well integrity logs were ran to properly assess whether enough hydraulic isolation was in place. To evaluate the bonding quality of the cement, two independent measurements were carried out across the 7-inch liner with the ultrasonic and sonic bond logs. A subsequent temperature survey was recorded to determine any geothermal anomaly, which could be indicative of fluid movement behind the casing. Finally, oxygen activation stations were conducted based on the cement log and temperature surveys to assure no water movement behind the casing. The ultrasonic and sonic bond log measurements showed an acceptable bond quality generally. However, the top part of Shuaiba formation up to LB exhibited relatively lower bond quality. The subsequent temperature and oxygen activation logs indicated that the zonal hydraulic isolation was achieved by showing no water movement behind the 7-inch liner. The two complementary surveys helped to take the proper forward decision for this well to go ahead with the planned perforation without cement remedial squeeze, since enough hydraulic isolation was proved to be in place behind the 7-inch liner. Additionally, this saved the rig utilization time and cost by avoiding unnecessary remedial operation. This is usually a heavy-duty operation, which takes time and induces holes in the casing that should be avoided, knowing this type of operation only provides a very marginal gain in terms of isolation. Furthermore, the well is currently producing at 0% water cut after completion. The proper cement design using light weight cement and optimized casing-landing plan were crucial to achieve good cement placement against formation. The use of the right well integrity approach helped to confirm that effective hydraulic isolation was achieved. Hence all these efforts resulted in the saved rig utilization time and cost by avoiding unnecessary squeeze intervention.

Pengembangan rencana induk ruang terbuka hijau berbasis masyarakat Desa Lambang Sari I, II, III Kecamatan Lirik Kabupaten Indragiri Hulu Riau

The utilization of green open space (RTH) in Desa Lambang Sari I, II, III, Kecamatan Lirik Kabupaten Indragiri Hulu used for ordinary services, such as gardening, exercising, and interacting, aims to determine its utilization based on activity types, the actor, vegetation types, utilization time, and its contributions on socio-cultural, economic, and environmental aspects, as well as to build collaboration between the community and the government to create an integrated RTH. The methods applied to achieve these goals included (a) Identifying the existing conditions of public RTH to determine its form, type, and function, (b) identifying the RTH utilization patterns including its types, implementation time, actors and forms of management, frequency of utilization, benefits of activity implementation and, (c) identifying the role of the community in the public RTH utilization, and (d) formulating the development of RTH needed by Desa Lambang Sari I, II, III. In the end, a development master plan was created based on the needs of the community, which became the reference for the development of this green open space.

GPU-accelerated molecular dynamics: State-of-art software performance and porting from Nvidia CUDA to AMD HIP

Classical molecular dynamics (MD) calculations represent a significant part of the utilization time of high-performance computing systems. As usual, the efficiency of such calculations is based on an interplay of software and hardware that are nowadays moving to hybrid GPU-based technologies. Several well-developed open-source MD codes focused on GPUs differ both in their data management capabilities and in performance. In this work, we analyze the performance of LAMMPS, GROMACS and OpenMM MD packages with different GPU backends on Nvidia Volta and AMD Vega20 GPUs. We consider the efficiency of solving two identical MD models (generic for material science and biomolecular studies) using different software and hardware combinations. We describe our experience in porting the CUDA backend of LAMMPS to ROCm HIP that shows considerable benefits for AMD GPUs comparatively to the OpenCL backend.

Well Leg Compartment Syndrome after Contralateral Femoral Neck ORIF

The authors present a case of WLCS after femoral neck fracture fixation. While this is a rare complication, a high index of suspicion should exist. Surgeons should use well leg holders with caution and limit utilization time. Alternative methods of positioning to allow for fluoroscopic imaging exist. WLCS remains a clinical diagnosis; intracompartmental measurements can be used but should be cautiously interpreted. When the diagnosis of WLCS is made, emergent fasciotomies of the affected compartments should be performed. Surgeons should be aware of this complication when using a well leg holder and the potential catastrophic consequences if left ignored.