bluuebunny/crossref_metadata_2025 huggingface dataset:
Mineralogy, Lithogeochemistry and Elemental Mass Balance of the Hydrothermal Alteration Associated with the Gold‐rich Batu Hijau Porphyry Copper Deposit, Sumbawa Island, Indonesia
Authors: Idrus Arifudin , Kolb Jochen , Meyer F. Michael
Published: August 2009

This paper discusses the mineralogy, whole‐rock geochemistry and elemental mass balance of the hydrothermal alteration zones within the Batu Hijau porphyry copper‐gold deposit, Sumbawa Island, Indonesia. The hydrothermal alteration and mineralisation developed in four stages, namely (i) the early stage consisting of a central copper‐gold‐bearing biotite (potassic), proximal actinolite (inner propylitic) and the distal chlorite‐epidote (outer propylitic) zones; (ii) the transitional stage represented by the chlorite‐sericite (intermediate argillic) zone; (iii) the late stages distinguished into the sericite‐paragonite (argillic) and pyrophyllite‐andalusite (advanced argillic) zones; and (iv) the very late stage typified by the illite‐sericite zone. In general, major elements (particularly Ca, Mg, Na and K) and some minor and rare earth elements decrease from the least altered rocks towards the late alteration zones as a consequence of the breakdown of Ca‐bearing hornblende, biotite and plagioclase. Chemical discrimination by means of millicationic R1‐R2 diagram indicates that R1 [4Si − 11(Na + K) − 2(Fe + Ti)] increases while R2[6Ca + 2Mg + Al] decreases with increasing alteration intensity, from least‐altered, through early, transitional, to late alteration zones. Rare earth elements‐chondrite (C1) normalised patterns also exhibit the depletion of the elements through the subsequent alteration zones. These results are consistent with the elemental mass balance calculation using the isocon method which shows that the degree of mass and volume depletion systematically increases during alteration. A decrease of the elements as well as mass and volume from early, through transitional to late alteration stages may imply a general decrease of the element activities in hydrothermal fluids during the formation of the alteration zones.
Geochemical Characteristics of Intrusive Rocks, Southeastern Mindanao, Philippines: Implication to Metallogenesis of Porphyry Copper‐gold Deposits
Authors: Suerte Leilanie Osano , Imai Akira , Nishihara Sho
Published: August 2009

This paper describes petrologic and geochemical characteristics of intrusive rocks associated with porphyry copper deposits in south‐eastern Mindanao, the Philippines, where the Kingking deposit is located. Intrusive rocks at the Kingking deposit, are classified into biotite‐bearing diorite porphyry, hornblende diorite porphyry and diorite porphyry. Intrusive rocks in other areas in south‐eastern Mindanao, including Batoto, Bukal, Maragusan, Masara, Amacan and Sumlog, are hornblende diorite porphyry and hornblende quartz diorite. They are adakitic in Sr/Y‐Y diagram, but not in La/Yb‐Yb diagram due to relatively low REE contents. The magmas are oxidizing as suggested by the high XMg of mafic silicate phenocrysts and SO3 contents of microphenocrystic apatite. An Oligocene‐Miocene diorite intrusive complex formed by calc‐alkaline, hydrous, oxidizing magma is considered to be associated with porphyry‐type copper‐gold mineralization.
A Preliminary Study on Skarn‐Related Calc‐silicate Rocks Associated with the Batu Hijau Porphyry Copper‐Gold Deposit, Sumbawa Island, Indonesia
Authors: Idrus Arifudin , Kolb Jochen , Meyer F.Michael , Arif Johan , Setyandhaka Dudy , Kepli Syamsul
Published: August 2009

Batu Hijau is a world‐class gold‐rich porphyry copper deposit, situated in Sumbawa Island, Indonesia. Deep drilling indicates that several intervals of calc‐silicate rock were intersected, where they are apparently interbedded with volcaniclastic rocks. The calc‐silicate rocks occur at the contact with copper‐gold‐bearing tonalite porphyries. The rocks are fine‐grained and granular with green, reddish‐brown and white layers. The green layers consist mostly of fine‐grained clinopyroxene (diopside and hedenbergite) and the reddish‐brown layers consist mostly of garnet (andradite), whereas the white layers are commonly composed of calcite and zeolite (chabazite). The calc‐silicate rocks were formed by contact metasomatism of andesitic volcaniclastic rocks, as it is calcic in composition. Paragenesis study reveals at least two stages of calc‐silicate mineralization. Stage 1 (prograde) is characterized by the presence of garnet (andradite), clinopyroxene (diopside and hedenbergite), anorthite and quartz at 340–360 C (high salinity 35–45 NaCl wt percentage eqn.). Stage 2 (retrograde) is characterized by chlorite and rare epidote at 280–300 C (low salinity 1–10 NaCl wt% eqn.). Late calcite ± quartz veinlets and calcite + chabazite veins/veinlets may also be related to this stage and cross cut the oldest mineral assemblages. Mineralization (magnetite, chalcopyrite and pyrite) may occur during the retrograde stage. Clinopyroxene and garnet were modified by Fe‐rich hydrothermal fluid (oxidizing condition) indicated by increase of Fe from core to rim of both the cogenetic minerals. The presence of the calc‐silicate rocks associated with massive magnetite‐chalcopyrite‐pyrite assemblage indicates the occurrence of calcic‐exoskarn surrounding the Batu Hijau porphyry copper‐gold deposit.
Dominant Inheritance of Primary Glenoid Dysplasia. Report of a Father and Son
Authors: Andrews Stuart N. , Smithson Sarah F. , Bunker Tim D.
Published: August 2009

We present two cases of primary glenoid dysplasia occurring in a father and son. The father presented at age 18 years and the son 7 years later at the age of 3 years. Both presented with recurrent shoulder pain and radiographs showed primary glenoid dysplasia. Our cases would strongly suggest autosomal dominant inheritance in this condition. Very few cases of familial occurrence of the disease have been reported. Since shoulder surgeons are the most likely physicians to encounter this condition knowledge of the pattern of inheritance may allow effective counselling.
Alignment of transposed mandibular lateral incisor and canine using removable appliances
Authors: Canoglu E , Kocadereli I , Turgut MD
Published: August 2009

The purpose of this paper was to present the management of a rarely encountered transposition anomaly involving the mandibular permanent lateral incisor and the canine. In the literature, the treatment of this type of anomaly involves fixed orthodontic appliances. The treatment of the present case, however, was performed with removable appliances. Transposition of the permanent mandibular right lateral incisor and the permanent mandibular right canine was detected in a 12 year old girl. The primary mandibular right canine was extracted to enable the distal movement of the permanent lateral incisor by the eruption force of the permanent canine. The transposed teeth were then aligned in the arch by using removable appliances. The forms of the teeth were changed with each other with composite restorations.
Complete or ultraconservative removal of decayed tissue in unfilled teeth
Authors: Ricketts D , Kidd E , Innes NPT , Clarkson JE
Published: August 2009

Background:  The treatment of deep dental decay has traditionally involved removal of all the soft demineralized dentine before a filling is placed. However, this has been challenged in three groups of studies which involve sealing soft caries into the tooth. The three main groups either remove no caries and seal the decay into the tooth, remove minimal (ultraconservative) caries at the entrance to a cavity and seal the remaining caries in, or remove caries in stages over two visits some months apart to allow the pulp time to lay down reparative dentine (the stepwise excavation technique).

Objectives:  To test the null hypothesis of no difference in the incidence of damage or disease of the nerve of the tooth (pulp), progression of decay and longevity of restorations irrespective of whether the removal of decay had been minimal (ultraconservative) or complete.

Search strategy:  The Cochrane Oral Health Group Trials Register, Cochrane Central Register of Controlled Trials (CENTRAL), MEDLINE, PubMed and EMBASE databases were searched. The reference lists in relevant papers were checked.

Selection criteria:  Randomized controlled trials and controlled clinical trials comparing minimal (ultraconservative) caries removal with complete caries removal in unrestored permanent and deciduous teeth.

Data collection and analysis:  Outcome measures recorded were exposure of the nerve of the tooth (pulp) during caries removal, patient experience of symptoms of pulpal inflammation or necrosis, progression of caries under the filling, time until the filling was lost or replaced. Due to the heterogeneity of the included studies the overall estimate of effect was calculated using a random‐effects model.

Main results:  Four studies met the inclusion criteria; two stepwise excavation studies and two ultraconservative caries removal studies. Partial caries removal in symptomless, primary or permanent teeth reduces the risk of pulp exposure. We found no detriment to the patient in terms of pulpal symptoms in this procedure and no reported premature loss or deterioration of the restoration.

Authors’ conclusions:  The results of this systematic review reject the null hypothesis of no difference in the incidence of damage or disease of the nerve of the tooth (pulp) irrespective of whether the removal of decay had been minimal (ultraconservative) or complete and accepts the null hypothesis of no difference in the progression of decay and longevity of restorations. However, the number of included studies is small and differ considerably.

Partial caries removal is therefore preferable to complete caries removal in the deep lesion, in order to reduce the risk of carious exposure. However, there is insufficient evidence to know whether it is necessary to re‐enter and excavate further but studies that have not re‐entered do not report adverse consequences.
From datalog rules to efficient programs with time and space guarantees
Authors: Liu Yanhong A. , Stoller Scott D.
Published: August 2009

This article describes a method for transforming any given set of Datalog rules into an efficient specialized implementation with guaranteed worst-case time and space complexities, and for computing the complexities from the rules. The running time is optimal in the sense that only useful combinations of facts that lead to all hypotheses of a rule being simultaneously true are considered, and each such combination is considered exactly once in constant time. The associated space usage may sometimes be reduced using scheduling optimizations to eliminate some summands in the space usage formula. The transformation is based on a general method for algorithm design that exploits fixed-point computation, incremental maintenance of invariants, and combinations of indexed and linked data structures. We apply the method to a number of analysis problems, some with improved algorithm complexities and all with greatly improved algorithm understanding and greatly simplified complexity analysis.
Self-stabilization preserving compiler
Authors: Dolev Shlomi , Haviv Yinnon , Sagiv Mooly
Published: August 2009

Self-stabilization is an elegant approach for designing fault tolerant systems. A system is considered self-stabilizing if, starting in any state, it converges to the desired behavior. Self-stabilizing algorithms were designed for solving fundamental distributed tasks, such as leader election, token circulation and communication network protocols. The algorithms were expressed using guarded commands or pseudo-code. The realization of these algorithms requires the existence of a (self-stabilizing) infrastructure such as a self-stabilizing microprocessor and a self-stabilizing operating system for their execution. Moreover, the high-level description of the algorithms needs to be converted into machine language of the microprocessor. In this article, we present our design for a self-stabilization preserving compiler. The compiler we designed and implemented transforms programs written in a language similar to the abstract state machine (ASM). The compiler preserves the stabilization property of the high level program.
A hybrid Nano/CMOS dynamically reconfigurable system—Part II
Authors: Zhang Wei , Jha Niraj K. , Shang Li
Published: August 2009

In Part I of this work, a hybrid nano/CMOS reconfigurable architecture, called NATURE, was described. It is composed of CMOS reconfigurable logic and interconnect fabric, and nonvolatile nano on-chip memory. Through its support for cycle-by-cycle runtime reconfiguration and a highly-efficient computation model, temporal logic folding, NATURE improves logic density and area-delay product by more than an order of magnitude compared to existing CMOS-based field-programmable gate arrays (FPGAs). NATURE can be fabricated using mainstream photo-lithography fabrication techniques. Thus, it offers a currently commercially feasible architecture with high performance, superior logic density, and excellent runtime design flexibility.

In Part II of this work, we present an integrated design and optimization flow for NATURE, called NanoMap. Given an input design specified in register-transfer level (RTL) and/or gate-level VHDL, NanoMap optimizes and implements the design on NATURE through logic mapping, temporal clustering, temporal placement, and routing. As opposed to other design tools for traditional FPGAs, NanoMap supports and leverages temporal logic folding by integrating novel mapping techniques. It can automatically explore and identify the best temporal logic folding configuration, targeting area, delay or area-delay product optimization. A force-directed scheduling technique is used to optimize and balance resource usage across different folding cycles. By supporting logic folding, NanoMap can provide significant design flexibility in performing area-delay trade-offs under various user-specified constraints. We present details of the mapping procedure and results for different architectural instances. Experimental results demonstrate that NanoMap can judiciously trade off area and delay targeting different optimization goals, and effectively exploit the advantages of NATURE.

Part I of this work will appear in JETC Vol. 5, No. 4.
Utilizing quantum dot transistors with programmable threshold voltages for low-power mobile computing
Authors: Wang Shuo , Dai Jianwei , Hasaneen El-Sayed , Wang Lei , Jain Faquir
Published: August 2009

Power consumption poses one of the fundamental barriers for deploying mobile computing devices in energy-constrained situations with varying operation conditions. In particular, leakage power is projected to increase exponentially in future semiconductor process nodes. This challenging problem is pressing for renewed focus on power-performance optimization at all levels of design abstract, from novel device structures to fundamental shifts in design paradigm. In this article, we propose to exploit the programmable threshold voltage quantum dot (QD) transistors to reduce leakage thereby improving the energy efficiency for mobile computing. The unique programmability and reconfigurability enabled by QD transistors extend our capability in design optimization for new power-performance trade-offs. Simulation results demonstrate the significant leakage reduction over conventional techniques.
The internet of ideas
Authors: Crowcroft Jon
Published: August 2009

As researchers we have a duty to communicate our ideas. As communications researchers, we are privileged to study the technology and phenomena that are so transforming human society. We seek to understand and enhance the very tools with which we can convey our contributions to human knowledge.

In Japan there is a mode of presentation called, Pecha Kucha, where speakers present 20 images for 20 seconds each, as a way to convey new experimental thoughts effectively. I am going to present 12 ideas, each one in that spirit. Rather than a retrospective of my work, or a vision for a possible future Internet Architectures, I want to engage in what I do in my daily work with graduate students, thinking of problems that need solving in existing communications systems, or simply new ways to build communications systems.

I do not expect more than one or two of these ideas to make it past first base, but there is value in learning how to apply one's critical faculties even when filtering out bad ideas. Metcalfe's law is that the value of the network is the square of the number of participants since each participant contributes new input for all other participants. In an Internet of ideas, then, this value is only achieved if we contribute our ideas freely.

Researchers censor ideas for various reasons, including that a new communications system must have a business case. The Internet itself (the Web, Facebook and Twitter) was created without any business case. Many startups end up in a business that is nothing to do with the one-pager or elevator pitch they presented to the venture capitalists. We have no business filtering out ideas except if they are simply bad.

So here are my twelve research elevator pitches.
Cross-layer wireless bit rate adaptation
Authors: Vutukuru Mythili , Balakrishnan Hari , Jamieson Kyle
Published: August 2009

This paper presents SoftRate, a wireless bit rate adaptation protocol that is responsive to rapidly varying channel conditions. Unlike previous work that uses either frame receptions or signal-to-noise ratio (SNR) estimates to select bit rates, SoftRate uses confidence information calculated by the physical layer and exported to higher layers via the SoftPHY interface to estimate the prevailing channel bit error rate (BER). Senders use this BER estimate, calculated over each received packet (even when the packet has no bit errors), to pick good bit rates. SoftRate's novel BER computation works across different wireless environments and hardware without requiring any retraining. SoftRate also uses abrupt changes in the BER estimate to identify interference, enabling it to reduce the bit rate only in response to channel errors caused by attenuation or fading. Our experiments conducted using a software radio prototype show that SoftRate achieves 2X higher throughput than popular frame-level protocols such as SampleRate and RRAA. It also achieves 20% more throughput than an SNR-based protocol trained on the operating environment, and up to 4X higher throughput than an untrained SNR-based protocol. The throughput gains using SoftRate stem from its ability to react to channel variations within a single packet-time and its robustness to collision losses.
Cutting the electric bill for internet-scale systems
Authors: Qureshi Asfandyar , Weber Rick , Balakrishnan Hari , Guttag John , Maggs Bruce
Published: August 2009

Energy expenses are becoming an increasingly important fraction of data center operating costs. At the same time, the energy expense per unit of computation can vary significantly between two different locations. In this paper, we characterize the variation due to fluctuating electricity prices and argue that existing distributed systems should be able to exploit this variation for significant economic gains. Electricity prices exhibit both temporal and geographic variation, due to regional demand differences, transmission inefficiencies, and generation diversity. Starting with historical electricity prices, for twenty nine locations in the US, and network traffic data collected on Akamai's CDN, we use simulation to quantify the possible economic gains for a realistic workload. Our results imply that existing systems may be able to save millions of dollars a year in electricity costs, by being cognizant of locational computation cost differences.
PLUG
Authors: De Carli Lorenzo , Pan Yi , Kumar Amit , Estan Cristian , Sankaralingam Karthikeyan
Published: August 2009

New protocols for the data link and network layer are being proposed to address limitations of current protocols in terms of scalability, security, and manageability. High-speed routers and switches that implement these protocols traditionally perform packet processing using ASICs which offer high speed, low chip area, and low power. But with inflexible custom hardware, the deployment of new protocols could happen only through equipment upgrades. While newer routers use more flexible network processors for data plane processing, due to power and area constraints lookups in forwarding tables are done with custom lookup modules. Thus most of the proposed protocols can only be deployed with equipment upgrades. To speed up the deployment of new protocols, we propose a flexible lookup module, PLUG (Pipelined Lookup Grid). We can achieve generality without loosing efficiency because various custom lookup modules have the same fundamental features we retain: area dominated by memories, simple processing, and strict access patterns defined by the data structure. We implemented IPv4, Ethernet, Ethane, and SEATTLE in our dataflow-based programming model for the PLUG and mapped them to the PLUG hardware which consists of a grid of tiles. Throughput, area, power, and latency of PLUGs are close to those of specialized lookup modules.
Detailed diagnosis in enterprise networks
Authors: Kandula Srikanth , Mahajan Ratul , Verkaik Patrick , Agarwal Sharad , Padhye Jitendra , Bahl Paramvir
Published: August 2009

By studying trouble tickets from small enterprise networks, we conclude that their operators need detailed fault diagnosis. That is, the diagnostic system should be able to diagnose not only generic faults (e.g., performance-related) but also application specific faults (e.g., error codes). It should also identify culprits at a fine granularity such as a process or firewall configuration. We build a system, called NetMedic, that enables detailed diagnosis by harnessing the rich information exposed by modern operating systems and applications. It formulates detailed diagnosis as an inference problem that more faithfully captures the behaviors and interactions of fine-grained network components such as processes. The primary challenge in solving this problem is inferring when a component might be impacting another. Our solution is based on an intuitive technique that uses the joint behavior of two components in the past to estimate the likelihood of them impacting one another in the present. We find that our deployed prototype is effective at diagnosing faults that we inject in a live environment. The faulty component is correctly identified as the most likely culprit in 80% of the cases and is almost always in the list of top five culprits.
Spatio-temporal compressive sensing and internet traffic matrices
Authors: Zhang Yin , Roughan Matthew , Willinger Walter , Qiu Lili
Published: August 2009

Many basic network engineering tasks (e.g., traffic engineering, capacity planning, anomaly detection) rely heavily on the availability and accuracy of traffic matrices. However, in practice it is challenging to reliably measure traffic matrices. Missing values are common. This observation brings us into the realm of compressive sensing, a generic technique for dealing with missing values that exploits the presence of structure and redundancy in many real-world systems. Despite much recent progress made in compressive sensing, existing compressive-sensing solutions often perform poorly for traffic matrix interpolation, because real traffic matrices rarely satisfy the technical conditions required for these solutions.

To address this problem, we develop a novel spatio-temporal compressive sensing framework with two key components: (i) a new technique called Sparsity Regularized Matrix Factorization (SRMF) that leverages the sparse or low-rank nature of real-world traffic matrices and their spatio-temporal properties, and (ii) a mechanism for combining low-rank approximations with local interpolation procedures. We illustrate our new framework and demonstrate its superior performance in problems involving interpolation with real traffic matrices where we can successfully replace up to 98% of the values. Evaluation in applications such as network tomography, traffic prediction, and anomaly detection confirms the flexibility and effectiveness of our approach.
ROAR
Authors: Raiciu Costin , Huici Felipe , Handley Mark , Rosenblum David S.
Published: August 2009

To search the web quickly, search engines partition the web index over many machines, and consult every partition when answering a query. To increase throughput, replicas are added for each of these machines. The key parameter of these algorithms is the trade-off between replication and partitioning: increasing the partitioning level improves query completion time since more servers handle the query, but may incur non-negligible startup costs for each sub-query. Finding the right operating point and adapting to it can significantly improve performance and reduce costs.

We introduce Rendezvous On a Ring (ROAR), a novel distributed algorithm that enables on-the-fly re-configuration of the partitioning level. ROAR can add and remove servers without stopping the system, cope with server failures, and provide good load-balancing even with a heterogeneous server pool. We demonstrate these claims using a privacy-preserving search application built upon ROAR.
Matchmaking for online games and other latency-sensitive P2P systems
Authors: Agarwal Sharad , Lorch Jacob R.
Published: August 2009

The latency between machines on the Internet can dramatically affect users' experience for many distributed applications. Particularly, in multiplayer online games, players seek to cluster themselves so that those in the same session have low latency to each other. A system that predicts latencies between machine pairs allows such matchmaking to consider many more machine pairs than can be probed in a scalable fashion while users are waiting. Using a far-reaching trace of latencies between players on over 3.5 million game consoles, we designed Htrae, a latency prediction system for game matchmaking scenarios. One novel feature of Htrae is its synthesis of geolocation with a network coordinate system. It uses geolocation to select reasonable initial network coordinates for new machines joining the system, allowing it to converge more quickly than standard network coordinate systems and produce substantially lower prediction error than state-of-the-art latency prediction systems. For instance, it produces 90th percentile errors less than half those of iPlane and Pyxida. Our design is general enough to make it a good fit for other latency-sensitive peer-to-peer applications besides game matchmaking.
Web toolkits accessibility study
Authors: Mikovec Zdenek , Vystrcil Jan , Slavik Pavel
Published: August 2009

Access to increasing number of web applications is very good news especially for disabled people. These applications become richer and offer wide variety of services used in everyday's life (document creation, instant messaging, data storage, email communication, social networking, etc.). The problem is that at the same time these rich internet applications (RIA) become less accessible. There is a Web Accessibility Initiative (WAI) 2 related to W3C 1 which is trying to cope with this problem. In particular the Accessible Rich Internet Application suite of W3C (WAI-ARIA) 3 is describing how to improve the accessibility of dynamic web content and advanced user interface controls in rich internet applications.
Combating obesity trends in teenagers through persuasive mobile technology
Authors: Arteaga Sonia M. , Kudeki Mo , Woodworth Adrienne
Published: August 2009

Throughout the last decade, there has been an alarming increase in obesity prevalence among adults and teens throughout the world. Obesity has been found to increase the risk of developing diabetes, cardiovascular diseases, and some cancers. Due to the many health risks associated with obesity, an increase in prevalence has also pressured health care systems and the finances of the individual. Our research proposes to decrease obesity prevalence in adults by motivating teens to become or continue being physically active so that they can continue these healthy lifestyles as adults. Our goal is to encourage long term adoption of physically active behaviors by introducing a motivating application running on a mobile device. We use the Technology Acceptance Model, the Theory of Planned Behavior, the Theory of Meaning Behavior, and the Big 5 Personality Theory to guide our design.
The Semantic Web and e-Learning
Authors: Daly Chris
Published: August 2009

The goal of the Semantic Web is to provide the capacity for computers to understand Web content that exists on systems and servers across the Internet, ultimately adding value to the content and opening rich new data, information, and knowledge frontiers. Billions of Web pages are downloaded daily and are easily understood by humans. The knowledge gap exists for computers as these pages are only structured in the hypertext markup language (HTML) formatting language. When applied to the realm of e-learning, be it content interactions or learner management, the potential to add value is almost limitless.
Five Questions ... For George Siemens
Authors: Gualtieri Lisa Neal
Published: August 2009

George Siemens is the author of Knowing Knowledge and the recently released Handbook of Emerging Technologies for Learning. He is also associate director of research and development with the Learning Technologies Centre at the University of Manitoba and is the founder and president of Complexive Systems Inc., a learning lab focused on helping organizations develop integrated learning structures to meet the needs of global strategy execution. Lisa Gualtieri interviewed him about educational systems.
Increase Student Viewership with Striking Titles
Authors: Buros Scott
Published: August 2009

Few designers put much effort into creating a striking title for their e-learning projects. The title is usually a dull summary of the content or a cliché phrase. Rarely are we surprised by a creative presentation title.

If you make money on course access or increase the likelihood of viewership, you will want to incorporate some guidelines into your design practices right away. How can you create a striking title for your project? Here are a few tricks.
Connecting with Students through Inventive Marketing
Authors: Gualtieri Lisa Neal
Published: August 2009

Lisa Neal Gualtieri interviewed Keith Bourne about marketing online programs. Given the current economic state, what are the primary advantages and disadvantages of a solely online marketing strategy?
How Will Online Courses Weather the Economic Downturn?
Authors: Rowell Laurie
Published: August 2009

In the minds of most e-learning professionals, the University of Phoenix is closely tied to the concept of online courses, at least in part because the for-profit institution's pop-up advertisements for them are so ubiquitous. In fact, the university's students racked up a hefty $2.8 billion in federal loans and grants in fiscal year 2008, according to the government site Top 100 Recipients of Federal Assistance.

How the economic downturn is going to affect general college enrollment in 2009 is not yet clear, but the emerging consensus is that community colleges will likely get a bump in enrollment while four-year institutions may struggle. Online enrollment, however, is expected to do well across most institutions.
Patterns in e-Learning Standards and Specifications
Authors: Ellaway Rachel
Published: August 2009

E-learning standards and specifications display common patterns in the ways they support various aspects of educational and meta-educational activities and processes. This article considers the nature of these design patterns, and it suggests how (once identified) they can enable better educational technology designs, and how they can be analyzed to better understand the philosophy and practice of contemporary technology-mediated education.
Five Questions for Massood Zarrabian
Authors: Gualtieri Lisa
Published: August 2009

Massood Zarrabian is the CEO of Boston-based OutStart Inc., a global maker of technologies that help organizations transfer knowledge through formal and informal learning and social software. Zarrabian was interviewed about the importance of quality content and how it can give organizations a competitive edge.
Paying Teachers for Performance
Authors: Rowell Laurie
Published: August 2009

Basing teachers' raises, salary grade, bonuses, or commissions on their performance, or that of their students, is a topic that sparks energetic debate. Many argue merit pay has a long history of working in the private sector and there is no reason not to use similar metrics to pay for what you want in education. Those opposed say there is no clear-cut way to determine whether a teacher is performing well. But would offering teachers a bonus in the pay packet make for better student scores on these tests?
Threading, Tagging, and Higher-Order Thinking
Authors: Burns Mary
Published: August 2009

In much of the developing world, Web 2.0 applications remain little known and are rarely used as formal educational tools. In Indonesia, Education Development Center's (EDC) use of Web 2.0 tools as part of an online course appears to be yielding initially positive, and unanticipated, results. However, real impediments stand in the way. This past year a pilot program was launched in which a group of master trainers work as school-based coaches. To support coaches in their work with teachers, we constructed a Moodle-based online course with coaching-related readings, videos, and a discussion forum. To facilitate communication and information sharing, we built in a number of Web 2.0 tools: Diigo, VoiceThread, Ning, Dimdim, Flickr, Word Press, TeacherTube, and Curriki. (The accompanying list at the end of the article provides a brief description of these tools.)
15 Tips for Webinars
Authors: Fripp Patricia
Published: August 2009

Whenever you open your mouth, whether you're talking to one person or a thousand, you usually want to get a specific message across. How do you do that best when you are communicating through a webinar? What's different when the lecture is in the virtual world? How do you catch and keep your audience? Here are 15 tips.
Questions to Ask When Choosing an Online Graduate Program
Authors: Unrein Judy
Published: August 2009

An increasingly large group of professionals are looking to change careers or shore up their existing qualifications by going to graduate school. The options have never been more numerous thanks to online education, but it seems more complicated than ever to judge one program against another. Here are the key questions to ask before choosing an online educational program.
Things That Can't Be Taught
Authors: Schank Roger C.
Published: August 2009

Roger Schank here addresses an issue in education and training that's not well understood: It's not possible to teach or train individuals to do things that are not in line with their personalities. This matters because much of what we try to teach in school and train in the real world is really an attempt to alter personality.
Five Questions ... for Ben Sawyer
Authors: Gualtieri Lisa
Published: August 2009

Ben Sawyer, co-founder of Digitalmill, organizes the annual Games for Health Conference. The conference is produced by the Games for Health Project, which is sponsored by the Pioneer Portfolio of the Robert Wood Johnson Foundation. Leading the project, Ben has single-handedly pulled together a diverse community of people working on video games used in therapeutic practices, to teach health professionals, and for increasing education and adherence in patients with the goal of improving health through games and their associated technologies.
Teaching an Online Experience-based Leadership Course
Authors: Örtenblad Anders
Published: August 2009

Is it really possible to give online courses, with no physical meetings whatsoever, in leadership, where the students' learning to a large extent is based on experiences during the course in itself? Would it at the same time be possible to encourage critical thinking on a course like this, to create an online, experience-based, academic leadership course? I think it is, and I have tried to develop such a course.
Cog-Learn: An e-Learning Pattern Language for Web-based Learning Design
Authors: Coutinho Anacleto Junia , Talarico Neto Americo , Neris Vania Paula de Almeida
Published: August 2009

Designing online learning material is a difficult task for novice teachers who lack experience in their design. Patterns have emerged as means to capture design knowledge in context and offer solutions to designers. Cog-Learn is a pattern language aimed at supporting the design of learning material for e-learning systems. Here, we describe Co-Learn and discuss the patterns' identification and formalization processes through two case studies in which a set of cognitive strategies was applied with the goal of better organizing the content seen by the student. The purpose is to facilitate the student's interaction with the material's interface and, consequently, improve the learning process.
Evolution of a course on model checking for practical applications
Authors: Tahara Yasuyuki , Yoshioka Nobukazu , Taguchi Kenji , Aoki Toshiaki , Honiden Shinichi
Published: August 2009

Although model checking is expected as a practical formal verification approach for its automatic nature, it still suffers from difficulties in writing the formal descriptions to be verified and applying model checking tools to them effectively. The difficulties are found mainly in grasping the exact system behaviors, representing them in formal languages, and using model checking tools that fit the best to the verification problems. Even capable software developers need extensive education to overcome the difficulties. In this paper, we report our education course of practical applications of model checking in our education project called Top SE. Our approach consists of the following two features. First, we adopt UML as the design specification language and create the descriptions for each specific model checking tool from the UML diagrams, to enable easy practical application of model checking. Second, we build taxonomies of system behaviors, in particular behaviors of concurrent systems that are main targets of model checking. We can organize the knowledge and the techniques of practical model checking according to the taxonomies. The taxonomies are based on several aspects of system behaviors such as synchronization of transitions, synchronization of communications, and modeling of system environments. In addition, we make clear which model checking tools fit which types of systems. We treat the three different model checking tools: SPIN, SMV, and LTSA. Each tool has its specific features that make the tool easier or more difficult to be applied to specific problems than others. In our education course, we explain the taxonomies, the knowledge, and the techniques using very simple examples. We also assign the students exercises to apply the knowledge and the techniques to more complicated problems such as the dining philosopher problem, data copying between a DVD recorder and a hard disk recorder, and the alternating bit protocol.
Formal methods for future interoperability
Authors: Davies Jim , Gibbons Jeremy
Published: August 2009

Interoperability is a key challenge in software engineering, whether expressed in terms of the compatibility of different systems and protocols, in terms of compliance to industry standards, or--increasingly--in terms of the ability to share and re-use data gathered in different contexts. Formal methods are mathematical techniques for the precise description of systems properties and behaviour, and have an important role to play in the future provision of interoperable systems and data. This paper describes that role, and examines the implications for present-day training and education.
Computer science education in Peru
Authors: Gutiérrez Juan M. , Sanders Ian D.
Published: August 2009

Peruvian law requires that prospective school teachers be graduates of institutions which focus on preparing them into the pedagogical aspects of teaching. Unfortunately in the area of computing we believe that the prospective teachers do not receive enough subject specific training. In addition, the legal requirement means that CS graduates, without teaching qualifications, are disadvantaged if they attempt to become teachers. The result is that computer science education in high schools has become sterile and uninteresting. We provide an analysis of the academic status of these future teachers, with recommendations geared towards academic and curricular change in this area.
Security testing
Authors: Kreeger Matthew Nicolas
Published: August 2009

Considerable reliance and trust is placed on software performing as expected, even when subjected to malicious treatment. Arguably, the most significant consequences to both the software vendor and the user result from security vulnerabilities being present within released code. To fully appreciate and test for these types of issues knowledge outside of "general" software testing techniques is typically required. As such, we were keen to establish whether there was a relationship between the reported, general lack of security testing, and what is currently being taught at the undergraduate level.
Challenges in teaching a graduate course in applied cryptography
Authors: Garera Sujata , Vasconcelos Jorge
Published: August 2009

We describe our experience in creating and teaching a graduate course in cryptography at the Johns Hopkins University. We emphasize on the importance of such a course for a graduate student in an information security program. We discuss the course implementation and discuss the challenges in teaching this course to students from varied backgrounds. Based on our observations, we suggest specific improvements that could be applied to this course in the future.
The assignment problem
Authors: Rolfe Timothy J.
Published: August 2009

The linear assignment problem requires the determination of an optimal permutation vector for the assignment of tasks to agents. Even the backtracking implementation supports a rather powerful bounding function. Since the processing of permutation families (based on low-subscripted vector assignments) can be done independently of each other, one may examine parallel processing strategies, and discovery of instances in which the parallel execution is a very bad idea. Because of article size limitations, this article discusses only backtracking in parallel. A later article will address branch-and-bound in parallel.
Developing creativity in computer lessons
Authors: Lai Yiu-chi , Wong Tak-wah
Published: August 2009

When we examine the recent official curriculum documents published by the Curriculum Development Council in Hong Kong, we can observe that generic skills such as Collaboration Skills, Communication Skills, Creativity, Critical Thinking Skills, Problem-solving Skills etc. are identified as fundamental in helping students to learn. As most people agree that creativity is an essential element in the computer world, we are going to discuss the ways to develop students' creative ability in computer lessons in this paper.
Use writing class techniques to create software design documents
Authors: Santore John , Lorenzen Torben
Published: August 2009

Undergraduates in our Software Engineering course were able to code well but they wrote technical documents poorly. We found that using writing class techniques such as the use of graded, instructor commented drafts and template documents will considerably improve the quality of student technical writing projects.
The concept of nondeterminism
Authors: Armoni Michal , Ben-Ari Mordechai
Published: August 2009

Nondeterminism is a fundamental concept in computer science that appears in various contexts such as automata theory, algorithms and concurrent computation. We present a taxonomy of the different ways that nondeterminism can be defined and used; the categories of the taxonomy are domain, nature, implementation, consistency, execution and semantics. An historical survey shows how the concept was developed from its inception by Rabin & Scott, Floyd and Dijkstra, as well the interplay between nondeterminism and concurrency. Computer science textbooks and pedagogical software are surveyed to determine how they present the concept; the results show that the treatment of nondeterminism is generally fragmentary and unsystematic. We conclude that the teaching of nondeterminism must be integrated through the computer science curriculum so that students learn to see nondeterminism both in terms of abstract mathematical entities and in terms of machines whose execution is unpredictable.
The bologna process in European education
Authors: Porcheron Patrick
Published: August 2009

The Bologna Process aims to create a European Higher Education Area by 2010, in which students can choose from a wide and transparent range of high quality courses and benefit from smooth recognition procedures. The Bologna Declaration of June 1999 has put in motion a series of reforms needed to make European Higher Education more compatible and comparable, more competitive and more attractive for Europeans and for students and scholars from other continents (especially from USA). Reform was needed then and reform is still needed today if Europe is to match the performance of the best performing systems in the world, notably the United States and Asia. The talk will present the experience of the design and development of this process in the framework of a leading university in France.
ILE-idol
Authors: Fincher Sally , Cooper Stephen , Kölling Michael , Utting ian
Published: August 2009

This panel will showcase and compare three leading Initial Learning Environments (ILE): Alice, Greenfoot and Scratch.
An instructional approach to drive computer science courses through virtual learning environments
Authors: Buendía Félix , Cano Juan Carlos , Benlloch José Vicente
Published: August 2009

Nowadays, many universities have adopted Virtual Learning Environments for delivering and distributing educational resources. In the context of Computer Science (CS) courses, the use of these environments addresses several issues ranging from the application of instructional strategies to the selection of the most adequate learning platform. In this work, we propose an instructional approach to drive CS courses through virtual learning environments. The concept of driving a CS course adds a pedagogical value to the classical approach delivering educational resources. This pedagogical value is supported by applying instructional methods based on pedagogical patterns to design specific components of CS courses. The use of these pedagogical patterns helps to guide the deployment of Virtual Learning Environments (VLE) in CS courses enabling a connection between the course requirements and the VLE features. We have evaluated the proposed approach using an example of VLE called Poliformat. The evaluation focuses on the platform role as the road to drive Operating System courses during the 2005-06, 2006-07 and 2007-08 academic years. The evaluation results have contributed to a better understanding of how virtual learning environments can be used in CS courses and they confirm the benefits of applying instructional based approaches.
Coverage of course topics in a student generated MCQ repository
Authors: Denny Paul , Luxton-Reilly Andrew , Hamer John , Purchase Helen
Published: August 2009

A recent approach to engaging students in deep learning involves an online tool, PeerWise, through which students contribute multiple-choice questions to a shared question bank. Earlier work demonstrated a strong correlation between the use of PeerWise and student performance. In this study we investigate the quality of the MCQ repository created by students in an introductory programming course by analysing the range of topics on which students chose to write questions (i.e.~the repository coverage) without guidance from an instructor. We assess the repository coverage by comparing it with a common list of typical introductory programming topics, and by looking at its extent. We find that, despite having freedom to choose any topic, students created a repository that covered all the major topics in the curriculum.