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Enriching online flipped classrooms with feedback strategies
No full textFlipped classroom is a type of learning method where students are introduced to content at home while practicing, reflecting, or discussing it in class. In this study, we explore how different feedback strategies impact learning performance, motivation, and satisfaction in online flipped classrooms within a higher education context. Using a quasi-experimental design, 123 undergraduate students were randomly assigned to one of four conditions: teacher feedback, group peer feedback, dialogic peer feedback, and one-way peer feedback. Data were collected using a validated learning performance test, motivation, and satisfaction questionnaire with established reliability. Results indicated that group peer feedback significantly improved students’ learning performance, motivation, and satisfaction compared to other strategies. Additionally, those receiving teacher feedback excelled in the educational dimension of learning and reported greater satisfaction with domain-specific learning. These findings highlight the impact of different feedback strategies on student learning in online flipped classroom environments.</p
Memory Wall is not gone:A Critical Outlook on Memory Architecture in Digital Neuromorphic Computing
No full textThe rapid advancement of neuromorphic technology aims to address the memory wall challenge inherent in conventional von Neumann architectures. This paper critically examines current digital neuromorphic processors and their strategies to mitigate this bottleneck. While designed to bring computation closer to memory through distributed architectures, our findings indicate that on-chip memory systems, including SRAM and emerging technologies like STT-MRAM, have become significant consumers of area and energy, leading to a new memory wall. Through an analysis of energy and area efficiency in various memory technologies, we argue that without a re-evaluation of memory organization, digital neuromorphic processors may struggle to compete effectively in edge and embedded applications. We conclude with potential pathways for future research to overcome the limitations of on-chip memory in neuromorphic systems.</p
Measuring The Impact of Post-Quantum Cryptography on Complex Applications: A Case Study on Federated Identity Management
No full textThe arrival of quantum computers will significantly impact our current Internet infrastructures as quantum com- puters will be able to break current public key cryptography. This means that we need to replace cryptographic algorithms by quantum-safe alternatives, also known as Post Quantum Cryptography (PQC). Many protocols and architectures need to make this transition. While the Internet community is making steady progress on transitioning TLS to PQC, there are still many protocols for which action needs to be taken, especially in more complex scenarios where protocols span multiple layers of the stack. In this paper, we study such a complex scenario: Federated Identity architectures. The objective of these architec- tures is to allow access to multiple services using a single set of login credentials, improving convenience and security across different organizations or domains. In particular we examine the Hub’n’Spoke model, where multiple parties exchange data through a central hub. This hub manages most of the infrastruc- ture workload and deals with many heterogeneous devices and protocols, making it a perfect test case for the PQC transition. Using real-world data from an operator of a large academic identity federation, we benchmark five PQC algorithms finalized by NIST. We also quantify the toll this transition imposes on computational efficiency and hardware capacity. We show that while there is an ever increasing interest towards PQC adoption, many technical challenges remain unaddressed, showing that the Post Quantum transition process is fragmented, with many components of the ecosystem that are still insufficiently taken into consideratio
Hardness-dependent surface roughness threshold governing rolling contact fatigue crack initiation
Get PDFSurface roughness and material hardness strongly influence rolling contact fatigue (RCF) of rolling elements, yet a clear understanding of their combined effect on crack initiation remains limited. This study introduces a systematic approach to quantify the critical surface roughness threshold for fatigue crack initiation across hardness levels from 526 to 762 HV. Experimental characterization capturing hardness-dependent plasticity and surface integrity, including asperity-level hardness, residual stresses, and 3D topography of real surfaces, provides the key inputs to the numerical framework. To achieve computational efficiency and improve accuracy, the approach integrates boundary and finite element methods to simulate rolling contact conditions and predict the risk of surface crack initiation. Results show that material hardness plays a dual role in fatigue performance. Higher hardness limits surface plasticity but increases stress amplitudes near asperities. Depending on surface roughness, increased hardness can either improve or degrade fatigue behavior, shifting low-roughness surfaces toward high-cycle fatigue and high-roughness surfaces toward low-cycle fatigue. A threshold RMS roughness of 0.1–0.3 μm is identified, below which surface-initiated fatigue becomes improbable, and this threshold saturates at 0.3 μm for hardness levels above 700 HV. The findings suggest that crack initiation can contribute minimally or dominantly to total fatigue life depending on surface roughness and material hardness, and fatigue performance is not necessarily improved by increasing hardness, making it essential to optimize hardness according to service conditions and tribological requirements
Unlocking systemic change:a socio-technical perspective on sustainable innovation in the asphalt paving sector
No full textThe asphalt paving sector plays a vital role in transportation systems, enabling mobility and fostering economic growth, particularly in rapidly urbanizing societies. Driven by societal demands and international agreements, the sector faces growing pressure to transition toward sustainability. Yet, despite national and international efforts, the widespread implementation of sustainable innovations remains limited due to systemic barriers embedded in governance structures, institutional arrangements, and established industry practices.This PhD dissertation investigates the underlying dynamics behind the slow implementation of sustainable innovations in the asphalt paving sector. It examines the complex interactions among actors, rules, and practices that shape innovation processes. Drawing on systems thinking, the dissertation identifies persistent barriers that prevent promising innovations from gaining traction and reveals how these are interconnected and reinforced by broader structural conditions. By shedding light on the systemic nature of these obstacles and proposing actionable strategies, this research contributes to advancing the transition toward more sustainable road infrastructure
An open event-inventory database of rainfall-induced landslides and their environmental characteristics in the eastern Black Sea region of Türkiye
No full textDeveloping robust predictive methods for rainfall-triggered landslides is crucial for effective risk mitigation. Landslide event inventories provide essential data to understand the relationship between environmental factors and the spatiotemporal distribution of landslides. However, many mountainous regions prone to landslides still lack such comprehensive datasets. Türkiye is among these regions, experiencing frequent and often fatal landslides, yet only a few recorded landslide event inventories exist. In this study, we compiled eight inventories of rainfall-induced landslide events for the eastern Black Sea region of Türkiye. These inventories were generated using high-resolution imagery obtained from multiple sources, including satellite images, unmanned aerial vehicles (UAVs), and aircraft-based imagery. Using both univariate and multivariate statistical analyses, we analyzed the topographic, meteorological, lithologic, and anthropogenic factors influencing landslide occurrence. In evaluating the meteorological factors, we found that all eight landslide events were triggered by intense rainfall. However, our comparison revealed that spaceborne precipitation products consistently failed to capture the intense rainfall events that triggered landslides in the region. Our statistical analyses also showed that landslide occurrence rates are significantly higher in areas affected by anthropogenic land use and land cover (LU/LC) changes, particularly in zones where forested areas have been converted into agricultural plantations, such as those for tea and hazelnut
Microfluidic Thermal Flow Sensor with Extended Linear Range and Reduced Heat Dissipation Using a Shunt
No full textThis paper reports an inline microfluidic thermal flow sensor with extended linear range via a thermal shunt between the up- and downstream branch. The shunt is realised by refilling a 3 wide trench, such that the up-and downstream branch are thermally short-circuited. Additionally, the fabrication technology allows for the integration of highly-doped silicon heaters in the sidewalls of the freely-suspended microchannel. The sensor is characterised using nitrogen, isopropanol, and water. The shunt extends the linear range 30 times to 0.3 g/h. The heaters dissipate 3.5 mW of power resulting in a maximum temperature of 303 K, suitable for lab-on-a-chip applications. Furthermore, the fabrication technology is compatible with other inline sensors enabling further on-chip integration
Super-Vth Standard Cells With Improved EDP:Design and Silicon Validation in 65nm LP CMOS
No full textThe ever-increasing computational load and shrinking power budget have accentuated the need for energy-efficient operation of edge devices. In this article, a combination of static CMOS logic and Hybrid Pass transistor logic with Static CMOS output (HPSC), which has no floating or weak nodes and is thus as robust to noise as static CMOS logic, is used for designing toolchain-compatible super-Vth standard cells. Optimized HPSC variants of a 2/3-input XOR cell, a 2/3-input XNR cell, a half adder cell, a full adder cell, and two variants of a 1-bit multiply-accumulate combinational cell are presented in a commercial 65nm Low-Power CMOS technology. Measurements of test structures based on ring oscillators and dummy path techniques show an average frequency and average energy-delay product improvement of up to 30.3% and 32.5% respectively at typical conditions. The proposed cells’ superior performance compared to the commercially available standard cells is also highlighted in terms of propagation delay, leakage, and dynamic power consumption. This shows a promising approach for foundries or other commercial entities to improve digital design performance to about half a technology node at no additional cost
