The Feasibility of Reclaiming Shell Material from Investment Casting

This report examines the feasibility of investment shell component reclamation. Shell material components and their compositions are investigated with an industry survey, a study of the available literature, and analysis of specimen shell materials. physical properties and factors related to the reclamation and reuse of shell materials are described. Well known mineral processing methods are capable of producing concentrates of the various shell components. The theory and techniques of some applicable processes are discussed to assist with the development of reclamation operations. The recommended methods are; comminution by roll crushing, component concentration by screening, gravity settling or heavy medium separation. Aluminosilicate stucco (a major component of many investment shells) can be recovered in a form suitable for reuse as backup stucco. Zircon (a minor component in many shell compositions) -can be concentrated in an impure form, and subsequent caustic liberation treatments can remove the intermixed silica phases. Reuse of such zircon in investment casting may be possible but will require careful qualification testing. Fused and crystalline silica (major components of most shell compositions) are not reusable for investment casting. The feasibility of reclamation will be influenced by individual foundry choices of materials, composition and shell practice.HWRIC Project No. RRT-10NTIS PB92-16219

DEFY: A Deniable File System for Flash Memory

While solutions for file system encryption can prevent an adversary from determining the contents of files, in situations where a user wishes to hide even the existence of data, encryption alone is not enough. Indeed, encryption may draw attention to those files, as they most likely contain information the user wishes to keep secret, and coercion can be a very strong motivator for the owner of an encrypted file system to surrender their secret key. Herein we present DEFY, a deniable file system designed to work exclusively with solid-state drives, particularly those found in mobile devices. Solid-state drives have unique properties that render previous deniable file system designs impractical or insecure. Further, DEFY provides features not offered by any single prior work, including: support for multiple layers of deniability, authenticated encryption, and an ability to quickly and securely delete data from the device. We have implemented a prototype based on the YAFFS and WhisperYaffs file systems. An evaluation shows DEFY performs comparatively with WhisperYaffs

Astrophysicists on Twitter: An in-depth analysis of tweeting and scientific publication behavior

This paper analyzes the tweeting behavior of 37 astrophysicists on Twitter and compares their tweeting behavior with their publication behavior and citation impact to show whether they tweet research-related topics or not. Astrophysicists on Twitter are selected to compare their tweets with their publications from Web of Science. Different user groups are identified based on tweeting and publication frequency. A moderate negative correlation (p=-0.390*) is found between the number of publications and tweets per day, while retweet and citation rates do not correlate. The similarity between tweets and abstracts is very low (cos=0.081). User groups show different tweeting behavior such as retweeting and including hashtags, usernames and URLs. The study is limited in terms of the small set of astrophysicists. Results are not necessarily representative of the entire astrophysicist community on Twitter and they most certainly do not apply to scientists in general. Future research should apply the methods to a larger set of researchers and other scientific disciplines. To a certain extent, this study helps to understand how researchers use Twitter. The results hint at the fact that impact on Twitter can neither be equated with nor replace traditional research impact metrics. However, tweets and other so-called altmetrics might be able to reflect other impact of scientists such as public outreach and science communication. To the best of our knowledge, this is the first in-depth study comparing researchers' tweeting activity and behavior with scientific publication output in terms of quantity, content and impact.Comment: 14 pages, 5 figures, 7 table

Distribution and Habitat of the Southern Two-Lined Salamander, Eurycea cirrigera, in Will County, Illinois: Implications For Population Management and Monitoring

The southern two-lined salamander (Eurycea cirrigera) was found to occur at numerous localities within the Kankakee River State Park in Will County, Illinois. The species is restricted to small drainages within the Kankakee River valley that have flow consisting of groundwater that discharges at seeps or springs at or within the valley bluff. Cooler water temperatures and possibly other conditions that are associated with water derived from seep or spring sources may be important factors in determining salamander abundance. This is particularly relevant to larval habitat. These observations suggest that the spring or seep-fed larval habitat may be the primary limiting factor that may explain why the distribution of E. cirrigera is restricted in northern Illinois. It is proposed, that from a conservation management perspective, individual drainages or spring runs may best be considered as subpopulations of a metapopulation that are vulnerable to both deterministic and stochastic extinction. Educational field trips conducted by faculty of Chicago State University in 1996 and 1997 have provided preliminary data of relative population size and environmental conditions at some sites. With further refinement and standardization, these census techniques may have high potential for long-term monitoring to assess population status or detect decline. The inventory and census strategies that were used may also be adapted for use with other streamside salamander species that have similar life history traits and habitat requirements

Flexible Control of Composite Parameters in Max/MSP

Fundamental to the development of musical or artistic creative work is the ability to transform raw materials. This ability implies the facility to master many facets of the material, and to shape it with plasticity. Computer music environments typically provide points of control to manipulate material by supplying parameters with controllable values. This capability to control the values of parameters is inadequate for many artistic endeavors, and does not reflect the analogous tools and methods of artists working with physical materials. Rather than viewing parameters in computer-based systems as single points of control, the authors posit that parameters must become more multifaceted and dynamic in order to serve the needs of artists. The authors propose an expanded notion of how to work with parameters in computer-centric environments for time-based art. A proposed partial solution to this problem is to give parameters additional properties that define their behavior. An example implementation of these ideas is presented in Jamoma

Deterministic, Stash-Free Write-Only ORAM

Write-Only Oblivious RAM (WoORAM) protocols provide privacy by encrypting the contents of data and also hiding the pattern of write operations over that data. WoORAMs provide better privacy than plain encryption and better performance than more general ORAM schemes (which hide both writing and reading access patterns), and the write-oblivious setting has been applied to important applications of cloud storage synchronization and encrypted hidden volumes. In this paper, we introduce an entirely new technique for Write-Only ORAM, called DetWoORAM. Unlike previous solutions, DetWoORAM uses a deterministic, sequential writing pattern without the need for any "stashing" of blocks in local state when writes fail. Our protocol, while conceptually simple, provides substantial improvement over prior solutions, both asymptotically and experimentally. In particular, under typical settings the DetWoORAM writes only 2 blocks (sequentially) to backend memory for each block written to the device, which is optimal. We have implemented our solution using the BUSE (block device in user-space) module and tested DetWoORAM against both an encryption only baseline of dm-crypt and prior, randomized WoORAM solutions, measuring only a 3x-14x slowdown compared to an encryption-only baseline and around 6x-19x speedup compared to prior work

Astrophysicists’ conversational connections on Twitter

Because Twitter and other social media are increasingly used for analyses based on altmetrics, this research sought to understand what contexts, affordance use, and social activities influence the tweeting behavior of astrophysicists. Thus, the presented study has been guided by three research questions that consider the influence of astrophysicists’ activities (i.e., publishing and tweeting frequency) and of their tweet construction and affordance use (i.e. use of hashtags, language, and emotions) on the conversational connections they have on Twitter. We found that astrophysicists communicate with a variety of user types (e.g. colleagues, science communicators, other researchers, and educators) and that in the ego networks of the astrophysicists clear groups consisting of users with different professional roles can be distinguished. Interestingly, the analysis of noun phrases and hashtags showed that when the astrophysicists address the different groups of very different professional composition they use very similar terminology, but that they do not talk to each other (i.e. mentioning other user names in tweets). The results also showed that in those areas of the ego networks that tweeted more the sentiment of the tweets tended to be closer to neutral, connecting frequent tweeting with information sharing activities rather than conversations or expressing opinions

Evaluating Title VII Exposure in a Manufacturing Setting: A Case Study for Human Resource Management Students

Since Title VII of the Civil Rights Act of 1964 became an established part of the employment legal framework, human resource management professionals and compliance officers have played a vital role in evaluating their companies’ vulnerability to litigation based on perceived violations of Title VII, the Age Discrimination in Employment Act, the American with Disabilities Act, and other associated equality protection legislation. Factors to be considered include the plaintiff’s burden of proof, legitimate business defenses, and collection and evaluation of reliable data. This case study calls upon human resource management graduate students to evaluate the potential exposure of a defense manufacturer to gender discrimination litigation, and has been presented in an online learning environment