20 research outputs found

    Optimal Embedding of Functions for In-Network Computation: Complexity Analysis and Algorithms

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    We consider optimal distributed computation of a given function of distributed data. The input (data) nodes and the sink node that receives the function form a connected network that is described by an undirected weighted network graph. The algorithm to compute the given function is described by a weighted directed acyclic graph and is called the computation graph. An embedding defines the computation communication sequence that obtains the function at the sink. Two kinds of optimal embeddings are sought, the embedding that---(1)~minimizes delay in obtaining function at sink, and (2)~minimizes cost of one instance of computation of function. This abstraction is motivated by three applications---in-network computation over sensor networks, operator placement in distributed databases, and module placement in distributed computing. We first show that obtaining minimum-delay and minimum-cost embeddings are both NP-complete problems and that cost minimization is actually MAX SNP-hard. Next, we consider specific forms of the computation graph for which polynomial time solutions are possible. When the computation graph is a tree, a polynomial time algorithm to obtain the minimum delay embedding is described. Next, for the case when the function is described by a layered graph we describe an algorithm that obtains the minimum cost embedding in polynomial time. This algorithm can also be used to obtain an approximation for delay minimization. We then consider bounded treewidth computation graphs and give an algorithm to obtain the minimum cost embedding in polynomial time

    Sponsored data with ISP competition

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    We analyze the effect of sponsored data platforms when Internet service providers (ISPs) compete for subscribers and content providers (CPs) compete for a share of the bandwidth usage by the customers. Our analytical model is of a full information, leader-follower game. ISPs lead and set prices for sponsorship. CPs then make the binary decision of sponsoring or not sponsoring their content on the ISPs. Lastly, based on both of these, users make a two-part decision of choosing the ISP to which they subscribe, and the amount of data to consume from each of the CPs through the chosen ISP. User consumption is determined by a utility maximization framework, the sponsorship decision is determined by a non-cooperative game between the CPs, and the ISPs set their prices to maximize their profit in response to the prices set by the competing ISP. We analyze the pricing dynamics of the prices set by the ISPs, the sponsorship decisions that the CPs make and the market structure therein, and the surpluses of the ISPs, CPs, and users. This is the first analysis of the effect sponsored data platforms in the presence of ISP competition. We show that inter-ISP competition does not inhibit ISPs from extracting a significant fraction of the CP surplus. Moreover, the ISPs often have an incentive to significantly skew the CP marketplace in favor of the most profitable CP

    Emergency Detection and Monitoring Daily Routine of a Cattle using IOT

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    The main aim of this system is to smarten the infrastructure of cattle farming and to track the biological and physiological activities of cattle by implementing a noninvasive wearable by using IOT. In these, we come into picture the lightning sensor depend upon the climate it will turn on and off, temperature sensor will depend upon room temperature of cattle farm; methane sensor is used to check methane level in the farm; fire sensor depend upon any fire emergency and is responsible for smart lighting and also smart ventilation, it is also responsible for sprinkler actuation to make the infrastructure safer and smarter. We are also implementing automatic food releasing mechanism. We can identify the single cattle count with the help of the IR sensor

    Clinical Profile of Unilateral Proptosis in a Tertiary Care Centre

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    Proptosis, the forward protrusion of the eyeball, is a common manifestation of a wide variety of diseases inside the orbit and its spaces. Its diagnosis is usually a combined effort of the ophthalmologist, otolaryngologist, neurosurgeon, and radiologist. A clinical study of twenty-five cases with unilateral proptosis were studied in different age groups over a period of about 3 years under different headings like distribution, clinical features, radiological features, histopathological aspects, management, and outcomes of diseases. Proptosis measurement was done by simple/plastic ruler exophthalmometry, and diagnosis was made after a detailed clinical examination and ancillary tests. Treatment modality was decided based on radiological and histopathological examination reports, which included medical surgery, radiotherapy, and chemotherapy or a combination of all. In our study, most of the patients were in the age group of more than 60 years. The M : F ratio is 3 : 1. One case had a large proptosis of 18 mm above normal and 2 cases were as small as 3 mm. Diagnosis was mainly done by clinical features and confirmed by radiological and histopathological features. Most of them were treated medically (13 cases, i.e., 52%) and the rest by surgery with a combination of radiotherapy/chemotherapy (12 cases, i.e., 48%)

    SHARE AND USE

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    Android is one of the most user friendly mobile platforms that have grasped the attention of smart phone users around the globe. According to stats available there are 1.4 billion people who have used Android mobile platform. And this has led to the development of android application exponentially; there are around 2.8 million android applications available in play store. Many of the available application do not fit into low specification smart phones due to some reasons. Share and Use is an android application that lets you use another smart phones application by your phone without actually installing it on your phone. Share and Use lets user to use application installed on other phones and access applications on their smart phones. Share and Use helps phones with lower specification android phones to use applications that are not be able to install in them

    Redox regulation of GRPEL2 nucleotide exchange factor for mitochondrial HSP70 chaperone

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    Mitochondria are central organelles to cellular metabolism. Their function relies largely on nuclear-encoded proteins that must be imported from the cytosol, and thus the protein import pathways are important for the maintenance of mitochondrial proteostasis. Mitochondrial HSP70 (mtHsp70) is a key component in facilitating the translocation of proteins through the inner membrane into the mitochondrial matrix. Its protein folding cycle is regulated by the nucleotide-exchange factor GrpE, which triggers the release of folded proteins by ATP rebinding. Vertebrates have two mitochondrial GrpE paralogs, GRPEL1 and 2, but without clearly defined roles. Using BioID proximity labeling to identify potential binding partners of the GRPELs in the mitochondrial matrix, we obtained results supporting a model where both GRPELs regulate mtHsp70 as homodimers. We show that GRPEL2 is not essential in human cultured cells, and its absence does not prevent mitochondrial protein import. Instead we find that GRPEL2 is redox regulated in oxidative stress. In the presence of hydrogen peroxide, GRPEL2 forms dimers through intermolecular disulfide bonds in which Cys87 is the thiol switch. We propose that the dimerization of GRPEL2 may activate the folding machinery responsible for protein import into mitochondrial matrix or enhance the chaperone activity of mtHSP70, thus protecting mitochondrial proteostasis in oxidative stress.Peer reviewe
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