4,969 research outputs found
The Lived Jiu-Jitsu Training Experiences of Law Enforcement Officers in Rural Central Texas: A Transcendental Phenomenological Study
The purpose of this transcendental phenomenological study is to describe the Jiu-Jitsu training experiences of law enforcement officers in rural central Texas. Grappling and ground fighting martial arts are generally known as, and synonymous with, Jiu-Jitsu. This dissertation employs Brizin and Kernspechtâs general theory of combat, which is principally concerned with utilizing various means to direct ends. Brizin and Kernspecht used Carl von Clausewitzâs combat logic theory as their foundation. A qualitative approach was appropriate for this study and included collecting data from qualitative questionnaires, semi-structured interviews, and naturalistic observations. The qualitative questionnaires, semi-structured interviews, and naturalistic observations indicated that research participants found utility in Jiu-Jitsu training. The scenario-based exercises, peer and instructor discussions and feedback, and reflection opportunities enriched participantsâ learning experience and transferability to their day-to-day work. The data also supported the theoretical framework used in this study, which should give administrators confidence that officers should be allowed to learn principles and concepts, understand attacks and defense, develop skills and abilities, apply sequential techniques, and know which techniques to use. The participants attested to Jiu-Jitsuâs value in promoting self-development and improving safety for officers and the community. Having the space to learn, making personal investments, demonstrating learned concepts, and giving feedback were all consistent data points when answering the central and sub-research questions and describing the lived experiences of the officers who participated in this study. Applying the general theory of combat may help enhance force options and arrest and control tactics training, which might improve police-community relations through the safety of officers and the communities they serve
Resource-aware scheduling for 2D/3D multi-/many-core processor-memory systems
This dissertation addresses the complexities of 2D/3D multi-/many-core processor-memory systems, focusing on two key areas: enhancing timing predictability in real-time multi-core processors and optimizing performance within thermal constraints. The integration of an increasing number of transistors into compact chip designs, while boosting computational capacity, presents challenges in resource contention and thermal management. The first part of the thesis improves timing predictability. We enhance shared cache interference analysis for set-associative caches, advancing the calculation of Worst-Case Execution Time (WCET). This development enables accurate assessment of cache interference and the effectiveness of partitioned schedulers in real-world scenarios. We introduce TCPS, a novel task and cache-aware partitioned scheduler that optimizes cache partitioning based on task-specific WCET sensitivity, leading to improved schedulability and predictability. Our research explores various cache and scheduling configurations, providing insights into their performance trade-offs. The second part focuses on thermal management in 2D/3D many-core systems. Recognizing the limitations of Dynamic Voltage and Frequency Scaling (DVFS) in S-NUCA many-core processors, we propose synchronous thread migrations as a thermal management strategy. This approach culminates in the HotPotato scheduler, which balances performance and thermal safety. We also introduce 3D-TTP, a transient temperature-aware power budgeting strategy for 3D-stacked systems, reducing the need for Dynamic Thermal Management (DTM) activation. Finally, we present 3QUTM, a novel method for 3D-stacked systems that combines core DVFS and memory bank Low Power Modes with a learning algorithm, optimizing response times within thermal limits. This research contributes significantly to enhancing performance and thermal management in advanced processor-memory systems
La traduzione specializzata allâopera per una piccola impresa in espansione: la mia esperienza di internazionalizzazione in cinese di Bioretics© S.r.l.
Global markets are currently immersed in two all-encompassing and unstoppable processes: internationalization and globalization. While the former pushes companies to look beyond the borders of their country of origin to forge relationships with foreign trading partners, the latter fosters the standardization in all countries, by reducing spatiotemporal distances and breaking down geographical, political, economic and socio-cultural barriers. In recent decades, another domain has appeared to propel these unifying drives: Artificial Intelligence, together with its high technologies aiming to implement human cognitive abilities in machinery. The âLanguage Toolkit â Le lingue straniere al servizio dellâinternazionalizzazione dellâimpresaâ project, promoted by the Department of Interpreting and Translation (ForlĂŹ Campus) in collaboration with the Romagna Chamber of Commerce (ForlĂŹ-Cesena and Rimini), seeks to help Italian SMEs make their way into the global market. It is precisely within this project that this dissertation has been conceived. Indeed, its purpose is to present the translation and localization project from English into Chinese of a series of texts produced by Bioretics© S.r.l.: an investor deck, the company website and part of the installation and use manual of the Aliquis© framework software, its flagship product. This dissertation is structured as follows: Chapter 1 presents the project and the company in detail; Chapter 2 outlines the internationalization and globalization processes and the Artificial Intelligence market both in Italy and in China; Chapter 3 provides the theoretical foundations for every aspect related to Specialized Translation, including website localization; Chapter 4 describes the resources and tools used to perform the translations; Chapter 5 proposes an analysis of the source texts; Chapter 6 is a commentary on translation strategies and choices
Discussion on drivers and proposition of approaches to support the transition of traditional electricity consumers to prosumers
In recent years, traditional power systems have undergone a significant transition, mainly
related to the massive penetration of Renewable Energy Sources (RES). More specifically, the
transformation of residential consumers into prosumers has been challenging to the traditional
operation of electricity markets. This transition brings new challenges and opportunities to
the power system, leading to new Business Model (BM). One widely discussed change is
related to a consumer-centric or prosumer-driven approach, promoting increased participation
of small consumers in power systems. The present thesis aims at discussing the recent BMs as
enablers of the increasing prosumersâ role in the energy market and power system worldwide,
deepening the discussion with a holistic view of the Brazilian context. To do so, it defines
the main features of prosumers and their general related regulation as well as possible market
designs within power systems. Moreover, the work intends to contribute to the knowledge,
identification and understanding of the main regulatory barriers and enablers for the development
of those BMs in the Brazilian energy market. In addition, it discusses enabling technologies to
properly create the conditions that sustain new prosumer-driven markets. Then, it presents a
comprehensive review of existing and innovative BMs and a discussion on their future roles in
modern power systems and, in the Brazilian regulatory framework seeking to guide the decisions
for the country to develop its political and regulatory environment in the future. Moreover, a
set of recommendations for promoting these BMs in the power system worldwide is provided
along with policy recommendations to promote prosumers aggregation in the Brazilian energy
sector. An important conclusion is that, even though economically possible, not all innovative
BMs can spread around the world due to regulatory issues. Seeking to further explore one of
the prosumer-driven approaches presented and the challenges imposed by this innovative BM,
a study of energy and reserve markets based on the Peer-to-Peer (P2P) structure is carried out.
This structure is very promising for the prosumersâ promotion but presents some challenges for
the network operation. A critical challenge is to ensure that network constraints are not violated
due to energy trades between peers and neither due to the use of reserve capacity. Therefore,
two methodologies are proposed. First, is proposed a three-step approach (P2PTDF), using
Topological Distribution Factors (TDF) to penalize peers responsible for violations that may
occur in the network constraints, ensuring a feasible solution. Second, it is proposed a new
integrated prosumers-DSO approach applied in P2P energy and reserve tradings that also ensures
the feasibility of both energy and reserve transactions under network constraints. The proposed
approach includes the estimation of reserve requirements based on the RES uncertain behavior
from historical generation data, which allows identifying RES patterns. The proposed models
are assessed through a case study that uses a 14-bus system, under the technical and economic
criteria. The results show that the approaches can ensure a feasible network operation.Nos Ășltimos anos, os sistemas tradicionais de energia passaram por uma transição significativa, principalmente relacionada Ă penetração massiva de fontes de energia renovĂĄveis (do
inglĂȘs, Renewable energy sources-RES). Mais especificamente, a transformação de consumidores
residenciais em prosumidores tem desafiado a atual operação do mercado de energia elétrica.
Essa transição traz novos desafios e oportunidades para o sistema elétrico, levando a novos
modelos de negĂłcios (do inglĂȘs, Business Models-BM). Uma mudança amplamente discutida
estĂĄ relacionada a uma abordagem centrada no consumidor ou direcionada ao prossumidor,
promovendo maior participação de pequenos consumidores nos sistemas de energia. A presente
tese tem como objetivo discutir os recentes BMs como facilitadores do crescente papel dos
prosumidores no mercado de energia e no sistema elétrico mundial, aprofundando a discussão
com uma visĂŁo holĂstica do contexto brasileiro. Para tanto, define as principais caracterĂsticas
dos prosumidores e sua regulamentação geral relacionada, bem como possĂveis designs de
mercado dentro dos sistemas de energia. Além disso, o trabalho pretende contribuir para o
conhecimento, identificação e compreensão das principais barreiras regulatórias e facilitadoras
para o desenvolvimento desses BMs no mercado brasileiro de energia. Assim como, discutir as
tecnologias importantes para criar adequadamente as condiçÔes que sustentam novos mercados
orientados ao consumidor final. Em seguida, apresenta uma revisão abrangente dos BMs existentes e inovadores e uma discussão sobre seus papéis futuros nos sistemas de energia modernos
e, no quadro regulatĂłrio brasileiro, buscando orientar as decisĂ”es para que o paĂs desenvolva
seu ambiente polĂtico e regulatĂłrio no futuro. AlĂ©m disso, um conjunto de recomendaçÔes
para promover esses BMs no sistema de energia em todo o mundo Ă© fornecido juntamente com
recomendaçÔes de polĂticas para promover a agregação de prosumidores no setor de energia
brasileiro. Uma conclusĂŁo importante Ă© que, mesmo sendo economicamente possĂvel, nem todos
os BMs inovadores podem se espalhar pelo mundo devido a obstĂĄculos regulatĂłrias. Buscando
explorar ainda mais uma das abordagens orientadas ao prosumidor apresentadas e os desafios
impostos por este BM inovador, Ă© realizado um estudo dos mercados de energia e de reserva com
base na estrutura ponto a ponto (do inglĂȘs, peer-to-peer-P2P). Esta estrutura Ă© muito promissora
para a promoção dos prosumidores mas apresenta alguns desafios para o funcionamento da rede.
Um desafio crĂtico Ă© garantir que as restriçÔes da rede nĂŁo sejam violadas devido a negociaçÔes
de energia entre pares e nem devido ao uso da capacidade de reserva. Portanto, duas metodologias sĂŁo propostas. Primeiramente, Ă© proposta uma abordagem em trĂȘs passos (P2PTDF),
utilizando Fatores de Distribuição TopolĂłgica (do inglĂȘs, Topological Distribution Factors-TDF
) para penalizar os peers responsåveis por violaçÔes que possam ocorrer nas restriçÔes da rede,
garantindo uma solução viåvel. Em segundo lugar, é proposta uma nova abordagem integrada
de prosumidores-DSO aplicada em transaçÔes P2P de energia e reserva que também garante a
viabilidade de transaçÔes de energia e reserva sob restriçÔes de rede. A abordagem proposta
inclui a estimativa dos requisitos de reserva com base no comportamento incerto da RES a partir
de dados históricos de geração, o que permite identificar padrÔes de RES. Os modelos propostos
são avaliados através de um estudo de caso que utiliza um sistema de 14 barras, sob os critérios
técnico e econÎmico. Os resultados mostram que as abordagens podem garantir uma operação
de rede viĂĄvel abrangendo energia e mercados de reserva
Programming parallel dense matrix factorizations and inversion for new-generation NUMA architectures
We propose a methodology to address the programmability issues derived from the emergence of new-generation shared-memory NUMA architectures. For this purpose, we employ dense matrix factorizations and matrix inversion (DMFI) as a use case, and we target two modern architectures (AMD Rome and Huawei Kunpeng 920) that exhibit configurable NUMA topologies. Our methodology pursues performance portability across different NUMA configurations by proposing multi-domain implementations for DMFI plus a hybrid task- and loop-level parallelization that configures multi-threaded executions to fix core-to-data binding, exploiting locality at the expense of minor code modifications. In addition, we introduce a generalization of the multi-domain implementations for DMFI that offers support for virtually any NUMA topology in present and future architectures. Our experimentation on the two target architectures for three representative dense linear algebra operations validates the proposal, reveals insights on the necessity of adapting both the codes and their execution to improve data access locality, and reports performance across architectures and inter- and intra-socket NUMA configurations competitive with state-of-the-art message-passing implementations, maintaining the ease of development usually associated with shared-memory programming.This research was sponsored by project PID2019-107255GB of Ministerio de Ciencia, InnovaciĂłn y Universidades; project S2018/TCS-4423 of Comunidad de Madrid; project 2017-SGR-1414 of the Generalitat de Catalunya and the Madrid Government under the Multiannual Agreement with UCM in the line Program to Stimulate Research for Young Doctors in the context of the V PRICIT, project PR65/19-22445. This project has also received funding from the European High-Performance Computing Joint Undertaking (JU) under grant agreement No 955558. The JU receives support from the European Unionâs Horizon 2020 research and innovation programme, and Spain, Germany, France, Italy, Poland, Switzerland, Norway. The work is also supported by grants PID2020-113656RB-C22 and PID2021-126576NB-I00 of MCIN/AEI/10.13039/501100011033 and by ERDF A way of making Europe.Peer ReviewedPostprint (published version
A study of unskilled migrant construction workers in developing countries
Over the past twenty years, migrants have become essential to the construction industryâs
workforce in developing countries. This thesis is a labour migration study and
investigates the involvement of migrant workers and their issues in the wider labour
market with a particular focus on the construction sector. Although there is research on
the living and working conditions of migrant workers and growing acknowledgement of
the construction industry being hazardous for low skilled workers in particular, there has
been little research on employment conditions given the new requirements that have put
considerable pressure on the industry.
This study takes a qualitative approach, with in-depth interviews with both employers and
employees in the construction industry. In-depth telephone interviews were conducted
with 12 managers from the UAE (n=5), and the KSA (n=7). In addition, data was
collected from the fieldwork in Thailand, which includes face-to face in-depth interviews
with managers (n=10) and with migrant workers (n=22). The experiences of the 44
participants in this study provide the basis for understanding the situation of migrant
construction workers. The aim is to find ways for improving the conditions of migrant
construction workers in developing countries.
Based on the experiences of the participants, this study positions migrant workers within
the construction industry by examining the factors that have the greatest impact on the
lived reality of work. It considers how they could enjoy positive migration and work
experiences in the sector that would allow them to both contribute to and benefit from the
new developments within the construction industry. The conceptual models were
designed based on the fundamentals of system thinking for a system of several elements
under the key catalysers migration and employment. It is vital that knowledge be gathered
about factors acting as force to changes within the construction industry to ensure that
policies and practices relating to migration, employment, Occupational Health and
Safety, and wellbeing are well evidenced. This thesis contributes to existing knowledge
by shaping the linkages that reveal the opinions, requirements, and experiences of migrant
construction workers. The study outlines recommendations for improving conditions for
migrant workers in construction sector
Design and Real-World Evaluation of Dependable Wireless Cyber-Physical Systems
The ongoing effort for an efficient, sustainable, and automated interaction between humans, machines, and our environment will make cyber-physical systems (CPS) an integral part of the industry and our daily lives. At their core, CPS integrate computing elements, communication networks, and physical processes that are monitored and controlled through sensors and actuators. New and innovative applications become possible by extending or replacing static and expensive cable-based communication infrastructures with wireless technology. The flexibility of wireless CPS is a key enabler for many envisioned scenarios, such as intelligent factories, smart farming, personalized healthcare systems, autonomous search and rescue, and smart cities.
High dependability, efficiency, and adaptivity requirements complement the demand for wireless and low-cost solutions in such applications. For instance, industrial and medical systems should work reliably and predictably with performance guarantees, even if parts of the system fail. Because emerging CPS will feature mobile and battery-driven devices that can execute various tasks, the systems must also quickly adapt to frequently changing conditions. Moreover, as applications become ever more sophisticated, featuring compact embedded devices that are deployed densely and at scale, efficient designs are indispensable to achieve desired operational lifetimes and satisfy high bandwidth demands.
Meeting these partly conflicting requirements, however, is challenging due to imperfections of wireless communication and resource constraints along several dimensions, for example, computing, memory, and power constraints of the devices. More precisely, frequent and correlated message losses paired with very limited bandwidth and varying delays for the message exchange significantly complicate the control design. In addition, since communication ranges are limited, messages must be relayed over multiple hops to cover larger distances, such as an entire factory. Although the resulting mesh networks are more robust against interference, efficient communication is a major challenge as wireless imperfections get amplified, and significant coordination effort is needed, especially if the networks are dynamic.
CPS combine various research disciplines, which are often investigated in isolation, ignoring their complex interaction. However, to address this interaction and build trust in the proposed solutions, evaluating CPS using real physical systems and wireless networks paired with formal guarantees of a systemâs end-to-end behavior is necessary. Existing works that take this step can only satisfy a few of the abovementioned requirements. Most notably, multi-hop communication has only been used to control slow physical processes while providing no guarantees. One of the reasons is that the current communication protocols are not suited for dynamic multi-hop networks.
This thesis closes the gap between existing works and the diverse needs of emerging wireless CPS. The contributions address different research directions and are split into two parts. In the first part, we specifically address the shortcomings of existing communication protocols and make the following contributions to provide a solid networking foundation:
âą We present Mixer, a communication primitive for the reliable many-to-all message exchange in dynamic wireless multi-hop networks. Mixer runs on resource-constrained low-power embedded devices and combines synchronous transmissions and network coding for a highly scalable and topology-agnostic message exchange. As a result, it supports mobile nodes and can serve any possible traffic patterns, for example, to efficiently realize distributed control, as required by emerging CPS applications.
âą We present Butler, a lightweight and distributed synchronization mechanism with formally guaranteed correctness properties to improve the dependability of synchronous transmissions-based protocols. These protocols require precise time synchronization provided by a specific node. Upon failure of this node, the entire network cannot communicate. Butler removes this single point of failure by quickly synchronizing all nodes in the network without affecting the protocolsâ performance.
In the second part, we focus on the challenges of integrating communication and various control concepts using classical time-triggered and modern event-based approaches. Based on the design, implementation, and evaluation of the proposed solutions using real systems and networks, we make the following contributions, which in many ways push the boundaries of previous approaches:
âą We are the first to demonstrate and evaluate fast feedback control over low-power wireless multi-hop networks. Essential for this achievement is a novel co-design and integration of communication and control. Our wireless embedded platform tames the imperfections impairing control, for example, message loss and varying delays, and considers the resulting key properties in the control design. Furthermore, the careful orchestration of control and communication tasks enables real-time operation and makes our system amenable to an end-to-end analysis. Due to this, we can provably guarantee closed-loop stability for physical processes with linear time-invariant dynamics.
âą We propose control-guided communication, a novel co-design for distributed self-triggered control over wireless multi-hop networks. Self-triggered control can save energy by transmitting data only when needed. However, there are no solutions that bring those savings to multi-hop networks and that can reallocate freed-up resources, for example, to other agents. Our control system informs the communication system of its transmission demands ahead of time so that communication resources can be allocated accordingly. Thus, we can transfer the energy savings from the control to the communication side and achieve an end-to-end benefit.
âą We present a novel co-design of distributed control and wireless communication that resolves overload situations in which the communication demand exceeds the available bandwidth. As systems scale up, featuring more agents and higher bandwidth demands, the available bandwidth will be quickly exceeded, resulting in overload. While event-triggered control and self-triggered control approaches reduce the communication demand on average, they cannot prevent that potentially all agents want to communicate simultaneously. We address this limitation by dynamically allocating the available bandwidth to the agents with the highest need. Thus, we can formally prove that our co-design guarantees closed-loop stability for physical systems with stochastic linear time-invariant dynamics.:Abstract
Acknowledgements
List of Abbreviations
List of Figures
List of Tables
1 Introduction
1.1 Motivation
1.2 Application Requirements
1.3 Challenges
1.4 State of the Art
1.5 Contributions and Road Map
2 Mixer: Efficient Many-to-All Broadcast in Dynamic Wireless Mesh Networks
2.1 Introduction
2.2 Overview
2.3 Design
2.4 Implementation
2.5 Evaluation
2.6 Discussion
2.7 Related Work
3 Butler: Increasing the Availability of Low-Power Wireless Communication Protocols
3.1 Introduction
3.2 Motivation and Background
3.3 Design
3.4 Analysis
3.5 Implementation
3.6 Evaluation
3.7 Related Work
4 Feedback Control Goes Wireless: Guaranteed Stability over Low-Power Multi-Hop Networks
4.1 Introduction
4.2 Related Work
4.3 Problem Setting and Approach
4.4 Wireless Embedded System Design
4.5 Control Design and Analysis
4.6 Experimental Evaluation
4.A Control Details
5 Control-Guided Communication: Efficient Resource Arbitration and Allocation in Multi-Hop Wireless Control Systems
5.1 Introduction
5.2 Problem Setting
5.3 Co-Design Approach
5.4 Wireless Communication System Design
5.5 Self-Triggered Control Design
5.6 Experimental Evaluation
6 Scaling Beyond Bandwidth Limitations: Wireless Control With Stability Guarantees Under Overload
6.1 Introduction
6.2 Problem and Related Work
6.3 Overview of Co-Design Approach
6.4 Predictive Triggering and Control System
6.5 Adaptive Communication System
6.6 Integration and Stability Analysis
6.7 Testbed Experiments
6.A Proof of Theorem 4
6.B Usage of the Network Bandwidth for Control
7 Conclusion and Outlook
7.1 Contributions
7.2 Future Directions
Bibliography
List of Publication
A Survey of FPGA Optimization Methods for Data Center Energy Efficiency
This article provides a survey of academic literature about field
programmable gate array (FPGA) and their utilization for energy efficiency
acceleration in data centers. The goal is to critically present the existing
FPGA energy optimization techniques and discuss how they can be applied to such
systems. To do so, the article explores current energy trends and their
projection to the future with particular attention to the requirements set out
by the European Code of Conduct for Data Center Energy Efficiency. The article
then proposes a complete analysis of over ten years of research in energy
optimization techniques, classifying them by purpose, method of application,
and impacts on the sources of consumption. Finally, we conclude with the
challenges and possible innovations we expect for this sector.Comment: Accepted for publication in IEEE Transactions on Sustainable
Computin
The Mogadishu Effect: America\u27s Failure-Driven Foreign Policy
The October 1993 Battle of Mogadishu, commonly referred to as âBlack Hawk Down,â transformed American foreign policy in its wake. One of the largest special operations missions in recent history, the failures in Somalia left not only the United States government and military in shock, but also the American people. After the nationâs most elite fighting forces suffered a nearly 50 percent casualty rate at the hands of Somali warlords during what many Americans thought was a humanitarian operation, Congress and the American people erupted in anger. Although the United States has continued to be seen as an overbearing global peacekeeping force in the thirty years since Somalia, the Battle of Mogadishu served as the turning point for a generational foreign policy shift that significantly limited future global intervention because of the overt publicization of battleâs aftermath in the media, domestic and international reactions, and a fear of repeating the same mistakes elsewhere. The first major American loss of life after the Cold War, the battle and the reaction that followed, known as the âMogadishu effect,â forced President Clinton to rethink the United Statesâ role internationally. Clinton and his administration struggled to convince the American people that involvement overseas, especially global peacekeeping, was vital to international order after becoming the worldâs sole superpower. Congressional hearings, presidential correspondence, government documents, poll results, and numerous media releases across Clintonâs presidency mark the distinct shift in American foreign policy that took place after Mogadishu. Although he inherited involvement in the United Nations mission in Somalia from George H.W. Bush, the failures in Somalia transformed Clintonâs humanitarian involvement in Haiti, Bosnia, and Rwanda, tarnishing the remainder of his presidency and shifting expectations of significant American involvement in international peacekeeping after the Cold War
- âŠ