Computing in the RAIN: a reliable array of independent nodes

The RAIN project is a research collaboration between Caltech and NASA-JPL on distributed computing and data-storage systems for future spaceborne missions. The goal of the project is to identify and develop key building blocks for reliable distributed systems built with inexpensive off-the-shelf components. The RAIN platform consists of a heterogeneous cluster of computing and/or storage nodes connected via multiple interfaces to networks configured in fault-tolerant topologies. The RAIN software components run in conjunction with operating system services and standard network protocols. Through software-implemented fault tolerance, the system tolerates multiple node, link, and switch failures, with no single point of failure. The RAIN-technology has been transferred to Rainfinity, a start-up company focusing on creating clustered solutions for improving the performance and availability of Internet data centers. In this paper, we describe the following contributions: 1) fault-tolerant interconnect topologies and communication protocols providing consistent error reporting of link failures, 2) fault management techniques based on group membership, and 3) data storage schemes based on computationally efficient error-control codes. We present several proof-of-concept applications: a highly-available video server, a highly-available Web server, and a distributed checkpointing system. Also, we describe a commercial product, Rainwall, built with the RAIN technology

Performance of the TOTEM Detectors at the LHC

The TOTEM Experiment is designed to measure the total proton-proton cross-section with the luminosity-independent method and to study elastic and diffractive pp scattering at the LHC. To achieve optimum forward coverage for charged particles emitted by the pp collisions in the interaction point IP5, two tracking telescopes, T1 and T2, are installed on each side of the IP in the pseudorapidity region 3.1 < = |eta | < = 6.5, and special movable beam-pipe insertions - called Roman Pots (RP) - are placed at distances of +- 147 m and +- 220 m from IP5. This article describes in detail the working of the TOTEM detector to produce physics results in the first three years of operation and data taking at the LHC.Comment: 40 pages, 31 figures, submitted to Int. J. Mod. Phys.

Myth Theory and Structuralism —A Study of Lévi- Strauss’s mythological Research from Myth and Meaning

Myth as a cultural phenomenon, reflects a period of human civilization development and change track. Under the influence of Marxist theory and psychoanalysis in his early years, Lévi-Strauss believed that the study of myth not only extended space as the main line and supplemented the early history which emphasized the dimension of time, but also explored the significance of “naturalizing man” in cultural studies. This paper discusses Lévi- Strauss’s views on the relationship between myth and science, myth and history, myth and music, as well as structuralism in his book myth and meaning, and discusses his understanding of self and existence in the study of myth

ACon: A learning-based approach to deal with uncertainty in contextual requirements at runtime

Context: Runtime uncertainty such as unpredictable operational environment and failure of sensors that gather environmental data is a well-known challenge for adaptive systems. Objective: To execute requirements that depend on context correctly, the system needs up-to-date knowledge about the context relevant to such requirements. Techniques to cope with uncertainty in contextual requirements are currently underrepresented. In this paper we present ACon (Adaptation of Contextual requirements), a data-mining approach to deal with runtime uncertainty affecting contextual requirements. Method: ACon uses feedback loops to maintain up-to-date knowledge about contextual requirements based on current context information in which contextual requirements are valid at runtime. Upon detecting that contextual requirements are affected by runtime uncertainty, ACon analyses and mines contextual data, to (re-)operationalize context and therefore update the information about contextual requirements. Results: We evaluate ACon in an empirical study of an activity scheduling system used by a crew of 4 rowers in a wild and unpredictable environment using a complex monitoring infrastructure. Our study focused on evaluating the data mining part of ACon and analysed the sensor data collected onboard from 46 sensors and 90,748 measurements per sensor. Conclusion: ACon is an important step in dealing with uncertainty affecting contextual requirements at runtime while considering end-user interaction. ACon supports systems in analysing the environment to adapt contextual requirements and complements existing requirements monitoring approaches by keeping the requirements monitoring specification up-to-date. Consequently, it avoids manual analysis that is usually costly in today’s complex system environments.Peer ReviewedPostprint (author's final draft

Red Lake Notes

A lady begs leave to submit to the attention and keeping of the Minnesota Academy of Natural Sciences, a small box of pottery fragments collected, for the most part, from various points upon the shores of Red Lake, Red Lake Ojibwa reservation, Beltrami county, Minnesota. These objects have been secured through the good offices of t:esident sub-agent Mr. Jonathan Taylor, and of his family; a considerable share of them having been obtained directly from the soil through the personal efforts of Mr. Taylor\u27s son, Elmer Hamilton. Rev. Fred Smith, native missionary at Red Lake sub-agency, has also kindly contributed groups of broken pottery herewith transmitted, which were collected at Black Duck Creek, and on lands between the mouth of that water-course and the agency

African fractals as a tool for transformative education in Africa

Nature is replete with repetitive patterns in diminishing scales. Similarly, cultures produce recursive patterns that characterize their specific social, cultural, economic and political organisation. These self-similar, variously scaled and mostly infinitive patterns are called fractals. The uniqueness of African fractals emanates from the culture of the African peoples. Particular elements of these fractals have contributed immensely in mathematical learning especially in modern computing. This paper contends that the inclusion of African fractal education in curricula at all levels in Africa have the potential to contribute to better understanding of African identity, and promote African centred education that forestalls the alienation of the African from their environment. The paper argues that the teaching of African fractals in Africa is a needed project to facilitate understanding of the intricacies between nature and humans. It should deepen understanding about the concept of embedded humanity expressed in ideas of Ubuntu; and help awaken African consciousness about possibilities beyond empiricism. Recommendations are made on ways to include African fractals in the syllabus in Africa using the Ghana’s pre-tertiary level (Senior High School) as an example

Anthropologists and the Bible

The anthropology of religion was shaped by – and sought to influence – new understandings of the scriptures. Maintaining an uneasy, often unacknowledged, usually one-sided dialogue with biblical scholarship, the Victorian anthropologists introduced new comparative perspectives. Succeeding schools of anthropology applied their own particular analytical methods. Over a period of 150 years, despite changes in intellectual fashions, the anthropology of the bible has been a testing ground for the anthropology of religion

End-To-End Latency of a Fault-Tolerant CORBA Infrastructure

This paper presents an evaluation of the end-to-end latency of a fault-tolerant CORBA infrastructure that we have implemented. The fault-tolerant infrastructure replicates the server applications using active, passive and semi-active replication, and maintains strong replica consistency of the server replicas. By analyses and by measurements of the running fault-tolerant infrastructure, we characterize the end-to-end latency under fault-free conditions. The main determining factor of the run-time performance of the fault-tolerant infrastructure is the Totem group communication protocol, which contributes to the end-to-end latency primarily in two ways: the delay in sending messages and the processing cost of the rotating token. To reduce the delay in sending messages for passive and semi-active replication, the position of the primary server replica on the Totem ring, the token rotation time, the processing time at the client, and the processing time at the server must be considered. For active replication, the presence of duplicate messages adversely affects the performance. However, if an effective sending-side duplicate suppression mechanism is implemented, active replication is more advantageous than both passive and semi-active replication because of the automatic selection of the most favorable position of the server replica that sends the first non-duplicate reply

The Possibilities of Converting Akan Totems into Textile Designs for Ceremonial Cloths:A Means for Checking the Abuse of Totems in Ghana

In the Ghanaian societies, totems are represented by either plant or animals, sculptural work, landscape or even a mythical entity revered by members of that particular social group. These  serve as an emblem of a particular family or a clan and often as a reminder of their ancestry and protection. In Ghana, almost every traditional ruler, chief or king has a totem. Many wildlife species are regarded as totems due to their historical or socio-cultural significance, however, they are seriously abused by hunters and other human activities. This study seeks to find out the possibilities of converting some selected totems from the Akans into textile designs  for cloths to be used during festive occasions as a means of education. This sensitizes the societies and  the  traditional rulers on the disappearance of those plants and animals  and the need to preserve the remaining few. As an art-studio based  practice, the study employs manual sketches of selected totems among the Asante and Kwehu clans  using pencils and Adobe Photoshop CS3,computer graphics software as the main  design tools. The study was based on qualitative research approach which made use of the art-studio practice and descriptive observational method of research. Purposive sampling technique was used to gather data from clan heads, people from centre for national Culture, lecturers from KNUST and Kumasi polytechnic,  students from KNUST and Kumasi polytechnic, textile retailers and  textile artists within Kumasi metropolis to establish the conceptual background for the study. Observation and unstructured interview guides were the main instruments used for data collection. The study concluded that converting totems into  textile design for ceremonial cloth was paramount to understanding of their importance and easily educate  the general public their philosophical and economic ideals. Keywords: totems, cloth, textile  design, ceremony, philosophy, communicatio