THE DESIGN AND ANALYSIS OF EXPERIMENTS. By Oscar Kempthorne. New York, John Wiley and Sons, Inc., 1952. 631 pp. $8.50. This book by a teacher of statistics (as well as a consultant for \"experimenters\") is a comprehensive study of the philosophical background for the statistical design of experiment. It is necessary to have some facility with algebraic notation and manipulation to be able to use the volume intelligently. The problems are presented from the theoretical point of view, without such practical examples as would be helpful for those not acquainted with mathematics. The mathematical justification for the techniques is given. As a somewhat advanced treatment of the design and analysis of experiments, this volume will be interesting and helpful for many who approach statistics theoretically as well as practically. With emphasis on the \"why,\" and with description given broadly, the author relates the subject matter to the general theory of statistics and to the general problem of experimental inference. MARGARET J. ROBERTSON

The Design and Analysis of Experiments

What will 5G be? What it will not be is an incremental advance on 4G. The previous four generations of cellular technology have each been a major paradigm shift that has broken backward compatibility. Indeed, 5G will need to be a paradigm shift that includes very high carrier frequencies with massive bandwidths, extreme base station and device densities, and unprecedented numbers of antennas. However, unlike the previous four generations, it will also be highly integrative: tying any new 5G air interface and spectrum together with LTE and WiFi to provide universal high-rate coverage and a seamless user experience. To support this, the core network will also have to reach unprecedented levels of flexibility and intelligence, spectrum regulation will need to be rethought and improved, and energy and cost efficiencies will become even more critical considerations. This paper discusses all of these topics, identifying key challenges for future research and preliminary 5G standardization activities, while providing a comprehensive overview of the current literature, and in particular of the papers appearing in this special issue.

What Will 5G Be

Recommender systems have developed in parallel with the web. They were initially based on demographic, content-based and collaborative filtering. Currently, these systems are incorporating social information. In the future, they will use implicit, local and personal information from the Internet of things. This article provides an overview of recommender systems as well as collaborative filtering methods and algorithms; it also explains their evolution, provides an original classification for these systems, identifies areas of future implementation and develops certain areas selected for past, present or future importance.

http://romisatriawahono.net/lecture/rm/survey/information%20retrieval/Bobadilla%20-%20Recommender%20Systems%20-%202013.pdf

Recommender systems survey

Cloud data centers host diverse applications, mixing workloads that require small predictable latency with others requiring large sustained throughput. In this environment, today's state-of-the-art TCP protocol falls short. We present measurements of a 6000 server production cluster and reveal impairments that lead to high application latencies, rooted in TCP's demands on the limited buffer space available in data center switches. For example, bandwidth hungry "background" flows build up queues at the switches, and thus impact the performance of latency sensitive "foreground" traffic.To address these problems, we propose DCTCP, a TCP-like protocol for data center networks. DCTCP leverages Explicit Congestion Notification (ECN) in the network to provide multi-bit feedback to the end hosts. We evaluate DCTCP at 1 and 10Gbps speeds using commodity, shallow buffered switches. We find DCTCP delivers the same or better throughput than TCP, while using 90% less buffer space. Unlike TCP, DCTCP also provides high burst tolerance and low latency for short flows. In handling workloads derived from operational measurements, we found DCTCP enables the applications to handle 10X the current background traffic, without impacting foreground traffic. Further, a 10X increase in foreground traffic does not cause any timeouts, thus largely eliminating incast problems.

/pdf/data-center-tcp-dctcp-4d3pj8xdal.pdf

Data center TCP (DCTCP)

This paper presents and evaluates two principles for wireless routing protocols. The first is datapath validation: data traffic quickly discovers and fixes routing inconsistencies. The second is adaptive beaconing: extending the Trickle algorithm to routing control traffic reduces route repair latency and sends fewer beacons.We evaluate datapath validation and adaptive beaconing in CTP Noe, a sensor network tree collection protocol. We use 12 different testbeds ranging in size from 20--310 nodes, comprising seven platforms, and six different link layers, on both interference-free and interference-prone channels. In all cases, CTP Noe delivers > 90% of packets. Many experiments achieve 99.9%. Compared to standard beaconing, CTP Noe sends 73% fewer beacons while reducing topology repair latency by 99.8%. Finally, when using low-power link layers, CTP Noe has duty cycles of 3% while supporting aggregate loads of 30 packets/minute.

/pdf/collection-tree-protocol-selhhlblmq.pdf

Collection tree protocol

In this article, we introduce a novel link layer cooperation technique in noisy wireless networks to improve overall system throughput and reliability, and to reduce the cost of retransmission and energy consumption. Under a cluster-based network design, Chase combining (Chase, IEEE Transactions on Communications 33(5):385---393, 1985) is used together with FEC to improve the link layer reliability. This approach is different from how combining is used in the conventional hybrid ARQ, which is in a sequential way. The analytical results and the simulations show that with the cooperation of nodes in a clustering network, the link reliability will be greatly improved with the same power consumption. We also show that not only transmission power is greatly reduced, but also the aggregate power consumption for a successful transmission and reception.

Energy-efficient cluster-based cooperative FEC in wireless networks

This paper generalizes the TCP Vegas congestion avoidance mechanism and proposes a model to use accumulation, buffered packets of a flow inside network routers, as a congestion measure on which a family of congestion control schemes can be derived. We call this model accumulation-based congestion control (ACC). We use a bit-by-bit fluid model to define the accumulation concept and develop a general control algorithm, which includes a set of control policies. The new prove its proportional fairness and global stability. The ACC model serves as a reference for packet network implementations. We show that TCP Vegas is one possible scheme, which fits into the ACC model. It is well known that Vegas suffer from round trip propagation delay estimation error and reverse path queuing delay. We therefore design a new scheme called Monaco, which solves these problems by employing an out-of-band receiver-based accumulation estimator, with minimal support from network routers. Analysis and simulations comparisons between Vegas and Monaco demonstrate the effectiveness of the Monaco accumulation estimator. We use ns-2 simulations to show that the static and dynamic performance of Monaco matches the theoretic results. One key issue regarding the ACC model in general, i.e., the scalability of router buffer requirement, is discussed.

/pdf/an-accumulation-based-congestion-control-model-27ha1206yv.pdf

An accumulation-based congestion control model

Solar photovoltaic (PV) systems have a utilization (or capacity) factor of 15-20% worldwide We propose to enhance the energy yield in a software-defined manner by complementing commodity solar PV systems with cloud-based IoT-controlled reflectors We also propose designs for brownfield and greenfield settings in solar farms We study a number of practical engineering issues including effect of solar azimuth, shadowing effects, ground coverage ratio (GCR) tradeoff, constraints on angular control etc Our designs can raise solar PV energy yield between 50-100% with modest tradeoffs on operational complexity, land requirements (ground coverage ratio) etc The software-defined IoT control allows a variety of current and future operational or business constraints to be flexibly factored in to tradeoff these factors versus economic gain (eg: levelized cost of energy, LCOE) The paper presents both simulation and experimental evidence for our system We are actively piloting this technology with solar PV developers and engineering, procurement, construction (EPC) companies in emerging markets

Photonic Energy Harvesting: Boosting Energy Yield of Commodity Solar Photovoltaic Systems via Software Defined IoT Controls

The Available Bit Rate (ABR) service has been developed to support data applications over Asynchronous Transfer Mode (ATM) The ABR service uses a closed-loop rate-based traffic management framework where the network divides left-over bandwidth among contending sources The ATM Forum traffic management group also incorporated open-loop control capabilities to make the ABR service robust to temporary network failures and source inactivity An important problem addressed was whether rate allocations of sources should be taken away if sources do not use them The proposed solutions, popularly known as the Use-It-or-Lose-It (UILI) policies, have had significant impact on the ABR service capabilities In this paper we discuss the design, development, and the final shape of these policies and their impact on the ABR service We compare the various alternatives through a performance evaluation

http://www.shivkumar.org/research/papers/uili.pdf

Shivkumar Kalyanaraman

Papers

Energy-efficient cluster-based cooperative FEC in wireless networks

An accumulation-based congestion control model

Photonic Energy Harvesting: Boosting Energy Yield of Commodity Solar Photovoltaic Systems via Software Defined IoT Controls

Use-it-or-lose-it policies for the available bit rate (ABR) service in ATM networks

An accumulation-based, closed-loop scheme for expected minimum rate and weighted rate services