System-level Implications Research Articles

Decentralized project delivery on the crypto commons: Conceptualization, governance mechanisms, and future research directions

This paper presents a first conceptualization for decentralized project delivery through the combination of blockchain technology and common pool resource governance theory, also known as the ”crypto commons”. While previous literature on project delivery models identifies the use of decentralized governance, there is not yet a holistic conceptualization nor a specific overview of governance applications that can be applied. To develop the concept, we use a literature review to synthesize fourteen blockchain governance mechanisms useful for managing the crypto-commons. Subsequently, we use systematic combining to identify twenty-two specific applications for decentralized project delivery in the construction industry, one of the largest project-based industries. Each application is briefly reviewed, and examples of their relevance to realize decentralized project delivery models are provided. We discuss the potential for novel forms of project delivery, but also the need for future research on the applications, as well as on the system level implications, the system design challenges, and the implementation barriers in the specific context of the construction industry. Overall, the concepts and mechanisms presented provide a theoretical foundation upon which future researchers can use to design novel decentralized project delivery models.

COBRRA: COntention-aware cache Bypass with Request-Response Arbitration

In modern multi-processor systems-on-chip (MPSoCs), requests from different processor cores, accelerators, and their responses from the lower-level memory contend for the shared cache bandwidth, making it a critical performance bottleneck. Prior research on shared cache management has considered requests from cores but has ignored crucial contributions from their responses. Prior cache bypass techniques focused on data reuse and neglected the system-level implications of shared cache contention. We propose COBRRA, a novel shared cache controller policy that mitigates the contention by aggressively bypassing selected responses from the lower-level memory and scheduling the remaining requests and responses to the cache efficiently. COBRRA is able to improve the average performance of a set of 15 SPEC workloads by 49% and 33% compared to the no-bypass baseline and the best-performing state-of-the-art bypass solution, respectively. Furthermore, COBRRA reduces the overall cache energy consumption by 38% and 31% compared to the no-bypass baseline and the most energy-efficient state-of-the-art bypass solution, respectively.

The Unique Practice of the Clinical Nurse Specialist.

The Unique Practice of the Clinical Nurse Specialist.

Use of General Practitioner Telehealth Services During the COVID-19 Pandemic in Regional Victoria, Australia: Retrospective Analysis.

In March 2020, the Australian Government expanded general practitioner (GP) telehealth services in response to the COVID-19 pandemic. This study sought to assess use patterns of GP telehealth services in response to changing circumstances (before and during the COVID-19 pandemic and with or without a lockdown) in regional Victoria, Australia. We conducted a secondary analysis of monthly Medicare claims data from July 2019 to June 2021 from 140 regional GP practices in Western Victoria. The longitudinal patterns of proportion of GP telehealth consultations stratified by type of consultation (ie, videoconference vs telephone) and by geographical, consumer, and consultation characteristics were analyzed. Telehealth comprised 25.8% (522,932/2,025,615) of GP consultations over the 2-year period. After the introduction of the Australian telehealth expansion policy in March 2020, there was a rapid uptake in GP telehealth services (including telephone and video services), from 0% before COVID-19 to 15% (11,854/80,922) of all consultations in March 2020, peaking at 55% (50,828/92,139) in August 2020. Thereafter, the use of telehealth declined steadily to 31% (23,941/77,344) in January 2021 and tapered off to 28% (29,263/103,798) in June 2021. Telephone services and shorter consultations were the most dominant form, and those aged 15-64 years had higher telehealth use rates than younger or older age groups. The proportion of video consultations was higher during periods with government-imposed lockdowns and higher in the most socioeconomically advantaged areas compared to less socioeconomically advantaged areas. Our findings support the continuation of telehealth use in rural and regional Australia post pandemic. Future policy must identify mechanisms to reduce existing equity gaps in video consultations and consider patient- and system-level implications of the dominant use of short telephone consultations.

The forgotten preconditions for a well-functioning internet

Abstract For decades, proponents of the Internet have promised that it would one day provide a seamless way for everyone in the world to communicate with each other, without introducing new boundaries, gatekeepers, or power structures. What happened? This article explores the system-level characteristics of a key design feature of the Internet that helped it to achieve widespread adoption, as well as the system-level implications of certain patterns of use that have emerged over the years as a result of that feature. Such patterns include the system-level acceptance of particular authorities, mechanisms that promote and enforce the concentration of power, and network effects that implicitly penalize those who do not comply with decisions taken by privileged actors. We provide examples of these patterns and offer some key observations, toward the development of a general theory of why they emerged despite our best efforts, and we conclude with some suggestions on how we might mitigate the worst outcomes and avoid similar experiences in the future.

Necessity-driven circular economy in low-income contexts: How informal sector practices retain value for circularity

Low-income informal sector contexts are rife in practices that retain value of materials and goods, but in the academic literature and policy debates these practices are seldom considered as part of the circular economy (CE). This is a major omission in CE discourse, as over 60 percent of the world’s employed population is in the informal sector and many of them make their living from circularity practices. Hence, our paper advances a globally covering understanding of CE by focusing on local practices constituting CE in the overlooked contexts of low-income informal markets of emerging economies, and on the motives behind the practices. To that end we introduce the notion of Necessity-Driven Circular Economy, defined as a set of locally embedded and interlinked formal and informal practices aimed at restoring and retaining the value of goods and materials for as long as possible, based on economic necessity and opportunities for income generation. We substantiate this conceptual work with our empirical findings from low-income urban communities in Brazil, India, and Tanzania. This allows us to capture the essential characteristics of necessity-driven circular economy. These characteristics draw attention to the social and cultural embeddedness and the interweaving of consumption and production in necessity-driven circular economy, as opposed to the dominant techno-economic and industry-focused circular economy conceptualizations that are typical in academic discourse and portray developed country contexts. Finally, we discuss conceptual and practical relevance of necessity-driven circular economy and point out its system-level implications for policymakers and businesses.

STeP-CiM: Strain-Enabled Ternary Precision Computation-In-Memory Based on Non-Volatile 2D Piezoelectric Transistors

We proposed 2D piezoelectric FET (PeFET)–based compute-enabled non-volatile memory for ternary deep neural networks (DNNs). PeFETs hinge on ferroelectricity for bit storage and piezoelectricity for bit sensing, exhibiting inherently amenable features for computation-in-memory of dot products of weights and inputs in the signed ternary regime. PeFETs consist of a material with ferroelectric and piezoelectric properties coupled with a transition metal dichalcogenide channel. We utilized (a) ferroelectricity to store binary bits (0/1) in the form of polarization (−P/+P) and (b) polarization-dependent piezoelectricity to read the stored state by means of strain-induced bandgap change in the transition metal dichalcogenide channel. The unique read mechanism of PeFETs enables us to expand the traditional association of +P (−P) with low (high) resistance states to their dual high (low) resistance depending on read voltage. Specifically, we demonstrated that +P (−P) stored in PeFETs can be dynamically configured in (a) a low (high) resistance state for positive read voltages and (b) their dual high (low) resistance states for negative read voltages, without afflicting a read disturb. Such a feature, which we named as polarization-preserved piezoelectric effect reversal with dual voltage polarity (PiER), is unique to PeFETs and has not been shown in hitherto explored memories. We leveraged PiER to propose a Strain-enabled Ternary Precision Computation-in-Memory (STeP-CiM) cell with capabilities of computing the scalar product of the stored weight and input, both of which are represented with signed ternary precision. Furthermore, using multi-word line assertion of STeP-CiM cells, we achieved massively parallel computation of dot products of signed ternary inputs and weights. Our array-level analysis showed 91% lower delay and improvements of 15% and 91% in energy for in-memory multiply-and-accumulate operations compared to near-memory design approaches based on 2D FET–based SRAM and PeFET, respectively. We also analyzed the system-level implications of STeP-CiM by deploying it in a ternary DNN accelerator. STeP-CiM exhibits 6.11× to 8.91× average improvement in performance and 3.2× average improvement in energy over SRAM-based near-memory design. We also compared STeP-CiM to near-memory design based on PeFETs showing 5.67× to 6.13× average performance improvement and 6.07× average energy savings.

Unintended consequences of measures implemented in the school setting to contain the COVID-19 pandemic: a scoping review.

With the emergence of SARS-CoV-2 in late 2019, governments worldwide implemented a multitude of non-pharmaceutical interventions in order to control the spread of the virus. Most countries have implemented measures within the school setting in order to reopen schools or keep them open whilst aiming to contain the spread of SARS-CoV-2. For informed decision-making on implementation, adaptation, or suspension of such measures, it is not only crucial to evaluate their effectiveness with regard to SARS-CoV-2 transmission, but also to assess their unintended consequences. To comprehensively identify and map the evidence on the unintended health and societal consequences of school-based measures to prevent and control the spread of SARS-CoV-2. We aimed to generate a descriptive overview of the range of unintended (beneficial or harmful) consequences reported as well as the study designs that were employed to assess these outcomes. This review was designed to complement an existing Cochrane Review on the effectiveness of these measures by synthesising evidence on the implications of the broader system-level implications of school measures beyond their effects on SARS-CoV-2 transmission. We searched the Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, Embase, four non-health databases, and two COVID-19 reference collections on 26 March 2021, together with reference checking, citation searching, and Google searches. We included quantitative (including mathematical modelling), qualitative, and mixed-methods studies of any design that provided evidence on any unintended consequences of measures implemented in the school setting to contain the SARS-CoV-2 pandemic. Studies had to report on at least one unintended consequence, whether beneficial or harmful, of one or more relevant measures, as conceptualised in a logic model. DATA COLLECTION AND ANALYSIS: We screened the titles/abstracts and subsequently full texts in duplicate, with any discrepancies between review authors resolved through discussion. One review author extracted data for all included studies, with a second review author reviewing the data extraction for accuracy. The evidence was summarised narratively and graphically across four prespecified intervention categories and six prespecified categories of unintended consequences; findings were described as deriving from quantitative, qualitative, or mixed-method studies. Eighteen studies met our inclusion criteria. Of these, 13 used quantitative methods (3 experimental/quasi-experimental; 5 observational; 5 modelling); four used qualitative methods; and one used mixed methods. Studies looked at effects in different population groups, mainly in children and teachers. The identified interventions were assigned to four broad categories: 14 studies assessed measures to make contacts safer; four studies looked at measures to reduce contacts; six studies assessed surveillance and response measures; and one study examined multiple measures combined. Studies addressed a wide range of unintended consequences, most of them considered harmful. Eleven studies investigated educational consequences. Seven studies reported on psychosocial outcomes.Three studies each provided information on physical health and health behaviour outcomes beyond COVID-19 and environmental consequences. Two studies reported on socio-economic consequences, and no studies reported on equity and equality consequences. We identified a heterogeneous evidence base on unintended consequences of measures implemented in the school setting to prevent and control the spread of SARS-CoV-2, and summarised the available study data narratively and graphically. Primary research better focused on specific measures and various unintended outcomes is needed to fill knowledge gaps and give a broader picture of the diverse unintended consequences of school-based measures before a more thorough evidence synthesis is warranted. The most notable lack of evidence we found was regarding psychosocial, equity, and equality outcomes. We also found a lack of research on interventions that aim to reduce the opportunity for contacts. Additionally, study investigators should provide sufficient data on contextual factors and demographics in order to ensure analyses of such are feasible, thus assisting stakeholders in making appropriate, informed decisions for their specific circumstances.

Use of the transtheoretical model in medication adherence: A systematic review.

Medication nonadherence is an important public health issue that has individual and system-level implications. Nonadherence can lead to negative health outcomes and illness, which in turn produce increased healthcare costs for both the individual and system. The transtheoretical model of change (TTM) can be a useful basis for interventions, as it can identify patients' current stages of change and guide them from nonadherence to adherence. The objective of this systematic review was to determine the utilization of the TTM to predict or improve medication adherence in patients with chronic conditions. A systematic review of current literature was conducted to obtain an overview of the use of TTM-informed interventions for medication adherence in chronic conditions. PubMed, Embase, PsycInfo and CINAHL databases were searched in July 2020. The methodological quality of the studies was evaluated using the Downs and Black checklist. The Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines were followed for data extraction, analysis, and reporting. Ten studies were included in the final data synthesis of this review. Eight of the reviewed studies supported the utility of TTM to predict or improve medication adherence in patients with chronic conditions, while two studies did not find any significant improvement in medication adherence after using a TTM-based intervention. The Downs and Black checklist revealed the overall methodological quality of the included studies to be fair [mean (SD)=16.3 (4.5) of a possible maximum score of 28]. This systematic review provides an overview of the utility of TTM in predicting and improving medication adherence in patients with chronic conditions. Although TTM-based interventions in patients with low or moderate medication adherence were effective, there were few studies identified, suggesting the need for further research.

Exploring the Design of Energy-Efficient Intermittently Powered Systems Using Reconfigurable Ferroelectric Transistors

In this article, we explore the design of energy-efficient intermittently powered systems (IPSs) using reconfigurable-ferroelectric transistors (R-FEFETs). Utilizing the dynamic tunability between volatile and nonvolatile modes of operation in R-FEFETs, we design nonvolatile flip-flops (NVFFs) and memory (NVM) suitable for IPS. We present two variants of R-FEFET-based NVFFs (RNVFFs): 1) with automatic backup and 2) with need-based backup. While the former offers high backup energy efficiency, the latter offers low normal operation energy. We also present an IPS-specific R-FEFET-based NVM (3T-R) with high energy efficiency compared with FEFET-based 2T NVM. Leveraging these nonvolatile circuits, we map the microcontroller unit (MCU) core registers of an IPS to RNVFFs and its on-chip memory to 3T-R. Subsequently, we analyze system-level implications of improving NVFFs and NVM individually by using R-FEFETs compared with existing FEFET-based designs. Our system-level simulations demonstrate that although we improve the register energy by 55%–67%, the total memory and system-level energy savings obtained from just improving the NVFFs (registers) in the microcontroller core are only 0.60%–5.78% and 0.31%–3.18%, respectively. However, improving the NVM by using 3T-R results in a much larger total memory and system-level energy savings in the range of 37%–40% and 20%–22%, respectively, in the context of a state-of-the-art IPS.

Hybrid posttensioned rocking (HPR) frame buildings: Low-damage vs low-loss paradox

The 2010-11 Canterbury Earthquake Sequence inflicted seismic losses worth more than $40B, which is about 25% of the GDP of New Zealand (as per 2011 data). More than 80% of these losses were insured, which comprised of more than $10B covered by the Earthquake Commission (a New Zealand crown entity providing insurance to residential property owners) and more than $22B (comprising of roughly equal split between domestic and commercial claims) by private insurers [1]. The scale of financial impact has been perceived to be disproportionately large given the building regulatory regime in New Zealand is relatively stringent and the earthquakes and aftershocks were of moderate magnitude. As it is well known that some of the major faults spread in the Wellington region and the subduction boundary passing through the centre of New Zealand can generate much bigger earthquakes (upwards of magnitude 8), people are left pondering whether New Zealand is able to cope with the financial impact of larger earthquakes. This fearful realisation gradually led to people being dissatisfied with merely life-safe buildings and demanding more resilient buildings that meet the objectives of performance based design; i.e. suffer less damage, incur less loss, and can remain functional after earthquakes.
 In light of the extensive building damage resulting in high financial loss in recent earthquakes, practicing engineers and researchers in New Zealand have been advocating for revising the current design approach to improve performance of new structures and infrastructure in future earthquakes [2-5]. As a result, large proportion of buildings constructed in the last decade (including those built to replace earthquake-damaged buildings) have shied away from the traditional damage-friendly ductile structural systems and instead adopted one of the new and emerging structural systems claimed to be “low-damage”. In many cases, the adopted structural systems are not covered by existing design standards and are approved as alternate solutions through expert peer review. The “low-damage” attribute of most structural systems has been validated by component (or sub-assembly) level experimental tests, but their interactions with other building components and implications of their use in buildings have not been rigorously scrutinised. Hence, the rushed adoption of some of these systems in buildings can surprise the engineering community in future earthquakes with mismatch between the expected and real performances of the buildings; akin to what New Zealand engineering fraternity is currently going through due to realisation of poor seismic performance of precast hollow-core flooring system that has been widely used in New Zealand buildings without rigorous scrutiny.
 One such “low-damage” structural system is precast post-tensioned rocking frames with supplemental energy dissipaters. This paper summarises the development of this structural system, critically reviews the literature reporting the seismic performance of this system, and qualitatively evaluates system-level implications of its use in buildings. This paper is intended to better inform engineers of the likely seismic performance of buildings with this structural system so that they can optimise its benefits by giving due consideration to its effect on other building components.

Incorporating Cascade Effects of Genetic Testing in Economic Evaluation: A Scoping Review of Methodological Challenges.

Cascade genetic testing is indicated for family members of individuals testing positive on a genetic test, and is particularly relevant for child health because of their vulnerability and the long-term health and economic implications. Cascade testing has patient- and health system-level implications; however cascade costs and health effects are not routinely considered in economic evaluation. The methodological challenges associated with incorporating cascade effects in economic evaluation require examination. The purpose of this scoping review was to identify published economic evaluations that considered cascade genetic testing. Citation databases were searched for English-language economic evaluations reporting on cascade genetic testing. Nineteen publications were included. In four, genetic testing was used to identify new index patients—cascade effects were also considered; thirteen assessed cascade genetic testing strategies for the identification of at-risk relatives; and two calculated the costs of cascade genetic testing as a secondary objective. Methodological challenges associated with incorporating cascade effects in economic evaluation are related to study design, costing, measurement and valuation of health outcomes, and modeling. As health economic studies may currently be underestimating both the cost and health benefits attributable to genetic technologies through omission of cascade effects, development of methods to address these difficulties is required.

Effect of AMB winding configurations on static and dynamic performances and power consumptions of the AMB-rotor system

Active magnetic bearings (AMBs) bring extraordinary benefits such as free of contact, elimination of lubrication, active control of rotor position, and a built-in monitoring system. In the design of AMBs, the bearing structure is of significance since it has an important impact on bearing performances. However, the effect of winding configurations of AMBs is still obscure. In this paper, the system-level implications of two radial AMB winding configurations termed the Ortho and the Cross types are investigated, including the bearing characteristics, power consumptions and rotor dynamic behaviors. The simulation results demonstrate that the Cross type contributes to larger load capacity in the direction of gravity. In condition of a heavier gravity load (−200 N), the Cross-type winding configuration saves power consumption with a percentage of 17.2% at steady state (20,000 rpm) and 12.7% considering unbalance mass during the run-up process. However, the rotor vibrations of the Cross type in case of external loads and unbalance mass are larger than the Ortho type. The proposed results of this paper provide some useful information for the AMB winding configuration design.

Preparing for Artificial Intelligence: Systems-Level Implications for the Medical Imaging and Radiation Therapy Professions

Innovations in artificial intelligence (AI) are driving a new industrial revolution, and as a result, the medical radiation sciences is experiencing transformational, open, beneficial, yet disruptive changes. Many studies have already been published on specific frontline examples where AI will improve cancer care, but discussions of how AI will change the medical radiation sciences and its associated professions at the systems level have been comparatively sparse. In this article, the system-level implications of AI on the medical radiation sciences are discussed, and recommendations are made on how professionals in this field may need to adapt in preparation for a future where AI will be an integral part of the health care system at all levels.

Heterogeneous Integration for HPC and Data Centers

Abstract Invited Session on HETEROGENEOUS INTEGRATION ROADMAP - Heterogeneous Integration for HPC and Data Centers. This TWG focuses on the system-level implications related to performance, power management, security, power distribution issues and others

Redefining Excellence: Teaching in Transition, From Test Performance to 21st Century Skills

This study examined classrooms in three, high performing, public secondary schools serving high need communities. Of 22 classes observed, we found approximately one third exhibited an instructional demand for 21st century skills. In many of the remaining classes, teachers appeared to apply misconceptions of 21st century skills, and unintentionally deployed those misconceptions to reinforce the narrow and shallow skill set associated with test-based accountability. Themes from teacher and administrator interviews support this finding. School and system level implications are discussed.

Crime and punishment as a social system: the case of prison overcrowding

PurposeThis paper presents an actor-based conceptualization of the increasing oscillatory pattern of prison overcrowding in Colombia. The research proposes a dynamic hypothesis that explains that unintended behavioural pattern as a result of delayed balance feedback loops shaped by decision-making processes of actors that intend to control crime. This system matches a well-known systemic archetype that explains those persistent oscillations. The paper also introduces a simulation model for testing that dynamic hypothesis and for delivering concrete courses of action. This work illustrates the relevance for policymakers to understand the dynamic complexity of social systems as the outcome of the agency of actors who take action to defend their own interests. Such actions ultimately form a complex web of interactions that drive the performance of such systems with unintended consequences. In particular, the construction of explicit models provides better chances of devising policies that consider the system-level implications of those interactions.Design/methodology/approachThis work uses system dynamics modelling. First, the paper presents a conceptual model anchored in operational thinking, which refers to the identification of actors and decisions, and the manner in which those decisions ultimately build the respective social system in which the oscillatory pattern emerges. Second, it identifies key feedback structures that result from those chains of decisions. Finally, the paper introduces a simulation model for suggesting policy implications for decisionmakers.FindingsThe increasing oscillatory pattern that prison overcrowding in Colombia has displayed over the last 20 years is the outcome of a wide variety of laws that increase sanctions on criminal conducts, a phenomenon known as “legislative inflation”. Such reactions against crime are propelled and sustained by society and policymakers as the result of static and linear thinking that simply delivers “more punishment” of crime – harsher legislation and longer prison terms – which ultimately boosts long-term prison overcrowding and further cycles of crime control and overcrowding. Such actions create permanent negative feedback loops that involve various material and information delays, which – coupled with the reinforcing feedback loops – explain the previously mentioned behavioural pattern. Through a system dynamics simulation model, this paper tests and explains the proposed dynamic hypothesis and shows how policymakers can enhance and develop their dynamic understanding to explore and design effective policies intended to tackle prison overcrowding.Practical implicationsThis paper presents a practical and concrete case that bridges the fields of criminal policy and prison management through systems thinking. It uses the case of prison overcrowding in Colombia to demonstrate the relevance of incorporating systemic thinking into the cognitive portfolio of policymakers if they aspire to improve complex systems.Originality/valueCriminal policy and prison management are different fields that typically belong to different traditions (law and criminal psychology for the former, public administration for the latter). The work presented here bridges those perspectives under a single engineering and systemic perspective that answers questions in both fields and serves as a unifying framework for designing more coherent criminal policies that meet the practical requirements and restrictions that prison management implies.

Strategizing in horizons and verizons

PurposeThe study has two related objectives. At the firm level of analysis, the author proposes that a clearer distinction between firms’ mediating functions and mediators could enhance the understanding of business network strategizing. Whereas firms’ mediating functions have received attention in IMP research, less focus has been given to organizations whose core business is mediation. At the system level of analysis, the study complements the perception of a network horizon with that of a network verizon. Whereas the horizon is closely associated with work on firms’ mediating functions, the network verizon is of particular interest to mediators. The paper aims to discuss these issues.Design/methodology/approachThis conceptual study combines IMP insights with strategic management theory.FindingsThe notion of a network horizon is important for business network strategizing, but also influences the perception of relevant network structures. These structures tend to be characterized by sequential interdependencies and a long-linked technology, often associated with physical products and production facilities. The notion of a network verizon highlights a network “depth” that has been unnoticed by previous work, which has focused on how narrow or wide a firm’s network horizon should be. The network horizon and the network verizon add strategizing options in terms of connecting key actors in the network to create additional value.Originality/valueThis paper concerns how IMP scholars understand boundaries and firms, and how perceptions of these influence business network strategizing. The study articulates a distinction between firms’ mediating functions and those organizations that fundamentally create value through mediating services. This distinction has system-level implications. In particular, the claim that the basis for a firm’s strategizing is its network horizon is discussed. The author proposes the notion of a “network Verizon,” providing a boundary perception of specific relevance to mediators. The network verizon portrays a network depth beyond both sequential tiers in a supply chain and links between different supply chains.

Behavioral rationality as a foundation for public policy studies

Cognitive processing applies to a single human being, yet most key social processes are organized in collectives, and connecting them is not a simple task. I review the basic ways in which social and behavioral scientists have tried to link the individual with the system, illustrating the progress that has been made in this endeavor. We are closer than we ever have been to producing a behavioral model that integrates cognitive science yet does not produce a confusing overabundance of findings that have systems level implications. I conclude that we may well be at a tuning point in which the fully rational model of human choice, currently used as the microfoundation for economics and the study of political institutions, is replaced by a more robust behavioral model of choice that relies on developments in the cognitive sciences.

Revisiting widely held SSD expectations and rethinking system-level implications

Storage applications leveraging Solid State Disk (SSD) technology are being widely deployed in diverse computing systems. These applications accelerate system performance by exploiting several SSD-specific characteristics. However, modern SSDs have undergone a dramatic technology and architecture shift in the past few years, which makes widely held assumptions and expectations regarding them highly questionable. The main goal of this paper is to question popular assumptions and expectations regarding SSDs through an extensive experimental analysis using 6 state-of-the-art SSDs from different vendors. Our analysis leads to several conclusions which are either not reported in prior SSD literature, or contradict to current conceptions. For example, we found that SSDs are not biased toward read-intensive workloads in terms of performance and reliability. Specifically, random read performance of SSDs is worse than sequential and random write performance by 40% and 39% on average, and more importantly, the performance of sequential reads gets significantly worse over time. Further, we found that reads can shorten SSD lifetime more than writes, which is very unfortunate, given the fact that many existing systems/platforms already employ SSDs as read caches or in applications that are highly read intensive. We also performed a comprehensive study to understand the worst-case performance characteristics of our SSDs, and investigated the viability of recently proposed enhancements that are geared towards alleviating the worst-case performance challenges, such as TRIM commands and background-tasks. Lastly, we uncover the overheads of these enhancements and their limits, and discuss system-level implications.