A project and competition to design and build a simple heat exchanger

To address a declining interest in process engineering, a project to design and build a compact heat exchanger was initiated in the second year of a four-year, multidisciplinary degree programme in biotechnology. The heat exchangers had a double-pipe configuration and employed plastic outer pipes and copper inner pipes of various diameters. Designs produced ranged from coiled inner pipes to various multi-pass arrangements and were assessed on the basis of heat transfer achieved per unit mean temperature difference per unit cost. The project, which also formed the basis of a competition, was very well received by students and gave them hands-on experience of engineering design and construction, as well as team work, problem solving, engineering drawing and the use of simple tools. Based on the success of this project, a similar problem based learning approach will be initiated in the third year of the same degree programme and will focus on bioethanol production

Development of a heat transfer and artificial neural networks teaching laboratory practical for biotechnology students

The paper describes a newly developed laboratory practical that teaches students how to develop an Artificial Neural Network model and its possible use in bio-processing. An emphasis is placed on giving students "hands on" experience with bio-processing equipment, namely bio-reactors and data acquisition systems in an attempt to help prepare them for work in bio-processing and chemical engineering industries

High-efficiency generation of nanomaterials via laser ablation synthesis in solution with in-situ diagnostics for closed-loop control

Driven by an ever-increasing demand for nanomaterials with specific functionalities, physical synthesis techniques such as Laser Ablation Synthesis in Solution (LASiS) have gained significant interest over in recent years. Commercial wet chemical synthesis methods, while having significantly higher nanomaterial yields than LASiS, typically have considerable negative environmental impact through the use of harmful reagents and solvents. LASiS therefore represents a route towards the sustainable “green” production of nanomaterials however the significant challenge to its commercialization is that of comparably low nanomaterial yields. Significant effort has been made towards increasing the production rates of LASiS, however many of the reported advances have relied on the use of high power (>20 W) or short pulse (<10 ps) laser systems which have high capital costs. Other advances have examined moving from batch production in small volumes towards the use of continuous production through the use of solvent flow systems. Combining these advances, we have developed a new system for nanomaterial generation via LASiS incorporating a low cost, low power (< 4W) Nd:YAG laser and solvent flow system for high-efficiency nanomaterial generation. This study has shown an increase in productivity from 2.5± 0.5 mg/hr for an 11 mL batch colloid, to continuous production yields of 17± 0.7 mg/hr under flow conditions

ANALYSIS OF CLIENT-SIDE ATTACKS THROUGH DRIVE-BY HONEYPOTS

Client-side cyberattacks on Web browsers are becoming more common relative to server-side cyberattacks. This work tested the ability of the honeypot (decoy) client software Thug to detect malicious or compromised servers that secretly download malicious files to clients, and to classify what it downloaded. Prior to using Thug we did TCP/IP fingerprinting to assess Thug’s ability to impersonate different Web browsers, and we created our own malicious Web server with some drive-by exploits to verify Thug’s functions; Thug correctly identified 85 out of 86 exploits from this server. We then tested Thug’s analysis of delivered exploits from two sets of real Web servers; one set was obtained from random Internet addresses of Web servers, and the other came from a commercial blacklist. The rates of malicious activity on 37,415 random websites and 83,667 blacklisted websites were 5.6% and 1.15%, respectively. Thug’s interaction with the blacklisted Web servers found 163 unique malware files. We demonstrated the usefulness and efficiency of client-side honeypots in analyzing harmful data presented by malicious websites. These honeypots can help government and industry defenders to proactively identify suspicious Web servers and protect users.OUSD(R&E)Outstanding ThesisLieutenant, United States NavyApproved for public release. Distribution is unlimited

Robustness Analysis of the Adaptive Periodic Noise Canceller Applied to Resonance Cancellation

In this paper the criteria determining robustness of a LMS-driven Adaptive Periodic Noise Canceller (APNC) when applied to the cancellation of coloured interference signals are investigated. The upper bound on the algorithm stepsize is the crucial quantity for determining robustness and here relevant expressions for this upper bound are developed, followed by experimental evaluation