Repository UNSAP (Universitas Sebelas April)
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Real-Time Generation of Annotated Video for Surveillance
No full textWe present a system that generates annotated video in realtime. Moving objects are first automatically extracted by means of video analysis and then coded using MPEG 4. Moreover, an MPEG 7 description of object features is generated. This description is used for automated event detection as well as for rendering. Rendering enhances important objects in the scene on the receiver side, thus facilitating the task of a surveillance operator. The performance of the system is demonstrated using four surveillance videos. Experiments show that objects enhancement can be achieved at low additional cost and illustrate how automated event detection is obtained by taking advantage of the physical scene description based on MPEG 7.LTSGR-E
Optimized Memory Access For Dynamically Scheduled High Level Synthesis
No full textDynamically-scheduled elastic circuits generated by High-Level Synthesis (HLS) tools are inherently out-of-order, following the flow of data rather than the evolution of an instruction pointer. Components of the circuit which access memory need to be connected to a Load-Store Queue (LSQ) that dynamically checks for memory dependencies, performs store ordering and forwarding, and allows unordered access to Random-Access Memory (RAM) whenever possible. While connecting every memory access (load/store) component to an LSQ ensures correctness of program execution, the hardware and power cost makes this solution unattractive. Statically ruling out dependencies allows circuits to access memory via lightweight components that use an arbitrator to handle RAM port sharing. Reducing the number of components using the LSQ allows the compiler to generate smaller queues which results in superlinear savings in hardware and power for the memory subsystem. This work describes additions to the Elastic Compiler (EC) that allow it to analyze algorithms expressed in LLVM-IR, an intermediate code representation, to rule out memory dependencies between load/store instructions and their underlying insights. These analyses leverage pointer analysis as well as array access patterns to narrow down the list of possibly dependent instructions. We also enhance the compiler to leverage our analyses and automatically generate relevant memory-access components for the circuit and to connect them to the relevant arbitrator or LSQ.LA
The synthetic boundary technique of analytical ultracentrifugation: A valuable tool to study structure formation processes online
No full textLMR
Comment on 'The effect of evaporation on the wicking of liquids into a metallic weave' by N. Fries, K. Odic, M. Conrath and M. Dreyer
No full textA recent paper reported capillary rise and evaporation experiments in metallic wicks, as well as a mathematical model. The authors found a consistent discrepancy between the model predictions and data: The model over-predicted the capillary height rise by about 20%. The model used assumes that the porous medium is either fully wet or dry, an assumption that is particularly unsuited to evaporation from the wick surface. An alternative variable-saturation model is proposed that provides a possible explanation for the 20% discrepancy reported by the authors.ECO
A review of thermal management of batteries with a focus on immersion cooling
No full textThe performance, cycle life and safety of batteries are strongly influenced by temperature. However, fast charging and discharging can significantly increase heat generation, causing the battery temperature to rise rapidly. Therefore, it is essential to employ suitable battery thermal management systems to maintain the battery temperature within an ideal range. Temperature uniformity plays a critical role in determining battery cycle life and operational performance. To evaluate the limitations of temperature uniformity across different battery thermal management systems, this review provides a comprehensive comparison of various cooling techniques. Among these, immersion cooling demonstrates the best temperature uniformity due to its high thermal efficiency and low thermal resistance. The two-phase immersion cooling system could maintain temperature and its uniformity within an ideal range even during ultra-high charging and discharging rates of up to 20C. Additionally, this review compares and evaluates different dielectric fluids used in immersion cooling to discuss the most adaptable coolants for battery systems and summarizes the latest developments in immersion cooling. Besides, the advantages and disadvantages of immersion cooling are summarized for battery thermal management regarding temperature fluctuation, temperature maldistribution under extreme conditions, and thermal runaway. Furthermore, the economic and environmental benefits of various battery thermal management systems are thoroughly analyzed. Immersion cooling demonstrates the lowest carbon footprint and superior environmental performance. Finally, the review highlights the critical challenges and future directions for immersion cooling, including advancements in dielectric fluids, system stability and integration, and battery safety. This study provides a comprehensive and up-to-date review of battery immersion cooling, offering valuable insights to advance battery thermal management systems and support the transition toward a sustainable economy and zero emissions.POWERLA
A Novel Nickel Pincer Complex in the Active Site of Lactate Racemase
No full textA recent study revealed the structure of the Ni-containing active site of lactate racemase. The Ni is coordinated by a SCS pincer ligand derived from a nicotinic acid mononucleotide.LSC
Pore fluid in experimental calcite-bearing faults: Abrupt weakening and geochemical signature of co-seismic processes
No full textWhile it is widely recognized that fluids influence fault strength and earthquake nucleation, propagation and arrest, their effects on co-seismic sliding friction are only conjectured. To shed light on these effects, 55 high velocity (>1ms-1) friction experiments were conducted at room temperature on Carrara marble samples in the presence of pore fluid (up to 15MPa pore pressure), room-humidity and "vacuum" (10-4mbar) conditions. In all the experiments, the friction coefficient evolved from a peak value of 0.6-0.8 to a steady-state value of 0.1 in about 1-1.5m of slip. However, experiments performed in the presence of pore fluid had a large and more abrupt decrease in friction at the initiation of sliding (65% after 20mm of slip), whereas experiments performed under vacuum and room humidity conditions showed initial velocity-strengthening behavior followed by a more gradual reduction in friction. This indicates that calcite-bearing rocks are more prone to slip in the presence of water. Under room-humidity conditions, CO2 was detected during the entire duration of the experiment. In the presence of pore fluid, HCO3 - and Ca2+ were detected for slips >0.1m. The lack of decarbonation products (HCO3 - and Ca2+) in pore fluid experiments for slip <0.1m implies that the abrupt weakening is not related to decarbonation (or that the abundance of the reaction products is below the resolution of the analytical methods). Given the modest thermal expansion of water, the estimated thermal pressurization during the abrupt weakening appears to be negligible. Instead, we suggest that abrupt weakening is due to subcritical crack-growth, hydrolytic weakening and brittle failure of the asperities on the sliding surfaces. Modeling shows that the occurrence in nature of co-seismic (water-present) decarbonation reactions similar to those triggered in the laboratory could yield sufficient reaction product to be detected in aquifers located in the proximity of active faults. © 2012 Elsevier B.V.LEM
Apparatus for producing gas mixture from hexamethyldisiloxane and carrier gas, e.g. oxygen, as process gas comprises filling packing arranged in a vertical column which can be cooled
No full textThe invention relates to a device for producing a gas mixture consisting of HMDSO and oxygen, whereby process gas is produced. In order to be able to continuously produce a large volume of process gas using such a device and to be able to withdraw the same at practical processable temperatures, the invention provides that a number of filling packages (2) are stacked in an elongated essentially vertical column (1) that can be cooled. In addition, an inlet tube (3), which is inserted into the column (1) from the exterior, and a gas outlet connection (6), which leads to the exterior, are secured in the upper area of said column (1). Devices (26) are also provided for measuring the temperature, the pressure and the amount of the exiting gas mixture. In addition, a distribution cup (29) which spans the cross-section of the column (1) and which is provided with gas flow-through openings (38) is placed underneath the inner discharge end (4) of the inlet tube (3).LOAAlternative title(s) :
(de) Vorrichtung zum herstellen eines gasgemisches
(fr) Dispositif permettant de produire un melange gazeux
(en) Device for producing a gas mixtur
TAHU SUMEDANG: Digital Public Service Implementation (A Study at Regional Government of Sumedang Regency)
Get PDFDigital transformation in public service delivery has become a key strategy in promoting government efficiency, effectiveness, and transparency. This study aims to analyze the effectiveness of implementing the TAHU SUMEDANG digital public service portal in the Sumedang Regency and identify the challenges encountered in its application. The research adopts a qualitative approach using a case study method, involving in-depth interviews with 10 key informants, participatory observations, and document analysis of regional public service policies and reports from 2023. The findings reveal that the TAHU SUMEDANG portal has increased service speed by up to 40% compared to the pre-digitalization period and expanded public access to administrative services, with a 65% increase in active users over the past year. Furthermore, service transparency has improved through an online service tracking system accessed by more than 12,000 users. These findings align with previous studies by Nugroho (2021) and Pratama and Wahyudi (2022), demonstrating that adopting digital technologies in local public services can accelerate bureaucratic responsiveness and enhance citizen satisfaction. However, the implementation still faces significant challenges, including limited digital infrastructure in 23% of peripheral villages, low digital literacy, especially among older people, and resistance from 30% of government staff who are not yet accustomed to the digital system. Compared to similar programs such as "SIPANDA" in Banyuwangi Regency and "Jakarta Smart City," Sumedang still has room for improvement regarding data integration and service simplification. In conclusion, digitalization through the TAHU SUMEDANG portal has positively impacted the quality of public services, yet it requires further strengthening in infrastructure, digital literacy, and staff capacity. The results of this study are expected to serve as strategic input for local governments in formulating inclusive, adaptive, and sustainable digital public service policies