272 research outputs found
Housing Ideology and Urban Residential Change: the rise of co-living in the financialized city
This article develops the concept of housing ideology in order to analyze the rise of co-living. Housing ideology refers to the dominant ideas and knowledge about housing that are used to justify and legitimize the housing system and its place within the broader political economy. Coliving is the term for privately operated, for-profit group rental housing. The article argues that the rise of co-living is supported by four key ideological elements—corporate futurism, technocratic urbanism, market populism and curated collectivism—which serve to legitimize co-living within the housing system and enable its profitability. The ideology of coliving appears to critique many elements of the contemporary urban housing system. But despite its critical self-image, co-living does not represent an alternative to today’s financialized urbanization. Ultimately, the article argues for the importance of understanding the role of housing ideologies in residential change
MDCC: Multi-Data Center Consistency
Replicating data across multiple data centers not only allows moving the data
closer to the user and, thus, reduces latency for applications, but also
increases the availability in the event of a data center failure. Therefore, it
is not surprising that companies like Google, Yahoo, and Netflix already
replicate user data across geographically different regions.
However, replication across data centers is expensive. Inter-data center
network delays are in the hundreds of milliseconds and vary significantly.
Synchronous wide-area replication is therefore considered to be unfeasible with
strong consistency and current solutions either settle for asynchronous
replication which implies the risk of losing data in the event of failures,
restrict consistency to small partitions, or give up consistency entirely. With
MDCC (Multi-Data Center Consistency), we describe the first optimistic commit
protocol, that does not require a master or partitioning, and is strongly
consistent at a cost similar to eventually consistent protocols. MDCC can
commit transactions in a single round-trip across data centers in the normal
operational case. We further propose a new programming model which empowers the
application developer to handle longer and unpredictable latencies caused by
inter-data center communication. Our evaluation using the TPC-W benchmark with
MDCC deployed across 5 geographically diverse data centers shows that MDCC is
able to achieve throughput and latency similar to eventually consistent quorum
protocols and that MDCC is able to sustain a data center outage without a
significant impact on response times while guaranteeing strong consistency
Optimizing floating guard ring designs for FASPAX N-in-P silicon sensors
FASPAX (Fermi-Argonne Semiconducting Pixel Array X-ray detector) is being
developed as a fast integrating area detector with wide dynamic range for time
resolved applications at the upgraded Advanced Photon Source (APS.) A burst
mode detector with intended \mbox{13 MHz} image rate, FASPAX will also
incorporate a novel integration circuit to achieve wide dynamic range, from
single photon sensitivity to x-rays/pixel/pulse. To achieve
these ambitious goals, a novel silicon sensor design is required. This paper
will detail early design of the FASPAX sensor. Results from TCAD optimization
studies, and characterization of prototype sensors will be presented.Comment: IEEE NSS-MIC 2015 Conference recor
Housing ideology and urban residential change: The rise of co-living in the financialized city
This article develops the concept of housing ideology in order to analyze the rise of co-living. Housing ideology refers to the dominant ideas and knowledge about housing that are used to justify and legitimize the housing system and its place within the broader political economy. Co-living is the term for privately operated, for-profit multiple occupancy rental housing. The article argues that the rise of co-living is supported by four key ideological elements—corporate futurism, technocratic urbanism, market populism and curated collectivism—which serve to legitimize co-living within the housing system and enable its profitability. The ideology of co-living appears to critique many elements of the contemporary urban housing system. But despite its critical self-image, co-living does not represent an alternative to today’s financialized urbanization. Ultimately, the article argues for the importance of understanding the role of housing ideologies in residential change
FactorJoin: A New Cardinality Estimation Framework for Join Queries
Cardinality estimation is one of the most fundamental and challenging
problems in query optimization. Neither classical nor learning-based methods
yield satisfactory performance when estimating the cardinality of the join
queries. They either rely on simplified assumptions leading to ineffective
cardinality estimates or build large models to understand the data
distributions, leading to long planning times and a lack of generalizability
across queries.
In this paper, we propose a new framework FactorJoin for estimating join
queries. FactorJoin combines the idea behind the classical join-histogram
method to efficiently handle joins with the learning-based methods to
accurately capture attribute correlation. Specifically, FactorJoin scans every
table in a DB and builds single-table conditional distributions during an
offline preparation phase. When a join query comes, FactorJoin translates it
into a factor graph model over the learned distributions to effectively and
efficiently estimate its cardinality.
Unlike existing learning-based methods, FactorJoin does not need to
de-normalize joins upfront or require executed query workloads to train the
model. Since it only relies on single-table statistics, FactorJoin has small
space overhead and is extremely easy to train and maintain. In our evaluation,
FactorJoin can produce more effective estimates than the previous
state-of-the-art learning-based methods, with 40x less estimation latency, 100x
smaller model size, and 100x faster training speed at comparable or better
accuracy. In addition, FactorJoin can estimate 10,000 sub-plan queries within
one second to optimize the query plan, which is very close to the traditional
cardinality estimators in commercial DBMS.Comment: Paper accepted by SIGMOD 202
S-Store: Streaming Meets Transaction Processing
Stream processing addresses the needs of real-time applications. Transaction
processing addresses the coordination and safety of short atomic computations.
Heretofore, these two modes of operation existed in separate, stove-piped
systems. In this work, we attempt to fuse the two computational paradigms in a
single system called S-Store. In this way, S-Store can simultaneously
accommodate OLTP and streaming applications. We present a simple transaction
model for streams that integrates seamlessly with a traditional OLTP system. We
chose to build S-Store as an extension of H-Store, an open-source, in-memory,
distributed OLTP database system. By implementing S-Store in this way, we can
make use of the transaction processing facilities that H-Store already
supports, and we can concentrate on the additional implementation features that
are needed to support streaming. Similar implementations could be done using
other main-memory OLTP platforms. We show that we can actually achieve higher
throughput for streaming workloads in S-Store than an equivalent deployment in
H-Store alone. We also show how this can be achieved within H-Store with the
addition of a modest amount of new functionality. Furthermore, we compare
S-Store to two state-of-the-art streaming systems, Spark Streaming and Storm,
and show how S-Store matches and sometimes exceeds their performance while
providing stronger transactional guarantees
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