Computer Engineering Commons^™

Fault And Defect Tolerant Computer Architectures: Reliable Computing With Unreliable Devices, George R. Roelke Iv

Theses and Dissertations

This research addresses design of a reliable computer from unreliable device technologies. A system architecture is developed for a "fault and defect tolerant" (FDT) computer. Trade-offs between different techniques are studied and yield and hardware cost models are developed. Fault and defect tolerant designs are created for the processor and the cache memory. Simulation results for the content-addressable memory (CAM)-based cache show 90% yield with device failure probabilities of 3 x 10(-6), three orders of magnitude better than non fault tolerant caches of the same size. The entire processor achieves 70% yield with device failure probabilities exceeding 10(-6). The required …

Inventions On Data Searching In Ldap- A Triz Based Analysis, Umakant Mishra

Umakant Mishra

Searching is one of the most basic operation provided by an LDAP server. LDAP offers a rich set of searching capabilities. The search operation allows a client to request the server to perform a search on its behalf. The search operation locates specific users or services in the directory tree. The LDAP server executes the search (or update) command and returns a response to the client. Upon receipt of a Search Request, a server will perform the necessary search of the DIT. The server will then return to the client a sequence of responses in separate LDAP messages. The search …

Evolution Of User Interfaces For The Visually Impaired- Part- 1, Umakant Mishra

Umakant Mishra

Physically or mentally challenged people cannot use a computer in the same way a normal people can. For example, a person with disability in hands cannot use a standard keyboard or mouse efficiently. People having hearing problem, visual challenge etc. cannot interact with a computer like a normal person. So it is necessary to specially design the computers, interfacing devices and software interfaces, which can be used by the physically challenged people.

There are many special devices like mouse, keyboard, pointers, and touch screens etc. to assist the visually challenged users. It is a challenge for the inventors and manufacturers …

High-Speed Digital And Mixed-Signal Components For X– And Ku–Band Direct Digital Synthesizers In Indium Phosphide Dhbt Technology, Steven Eugene Turner

Electronic Theses and Dissertations

Recently reported double heterojunction bipolar transistor (DHBT) devices manufactured in Indium Phosphide (InP) technology with ft and fmax both over 300 GHz enable advanced high-speed digital and mixed-signal circuits. In this thesis, the use of InP DHBT devices for high-speed accumulator circuits and X– and Ku–band direct digital synthesizer (DDS) circuits are investigated. At these frequencies, new technological challenges in the design of digital and mixed-signal circuits arise in areas including power consumption and clock distribution. This thesis addresses the speed/power tradeoffs in high-speed accumulator designs, the design of DDS circuits, and clock distribution simulation. The results of six accumulator …

Inventions On Menu Interfacing For Gui Applications, A Triz Based Analysis, Part-3, Umakant Mishra

Umakant Mishra

This article analyses 15 patents on Menu System from a TRIZ perspective to find out their IFRs and Contradictions. The previous two parts of this article analysed ten patents on the menu interfaces. This part analyses five more patents from TRIZ perspective and draws out the conclusion that the TRIZ process and methodology is perfectly applicable to software inventions.

Post Register Allocation Spill Code Optimization, Christopher Lupo, Kent Wilken

Computer Science and Software Engineering

A highly optimized register allocator should provide an efficient placement of save/restore code for procedures that contain calls. This paper presents a new approach to placing callee-saved save and restore instructions that generalizes Chow's shrink-wrapping technique (Chow 1988). An efficient, profile-guided, hierarchical spill code placement algorithm is used to analyze the structure of a procedure to calculate the minimum dynamic execution count locations to place callee-saved save and restore code. The algorithm is implemented in the Gnu Compiler Collection and has been tested on the SPEC CPU2000 Integer Benchmark suite. Results show that the technique reduces the number of dynamic …

Inventions On Menu Interfacing For Gui Applications, A Triz Based Analysis, Part-2, Umakant Mishra

Umakant Mishra

The first part of the article analyzed five patents on menu interfaces. This part analyses five more patents from TRIZ perspective to find out their IFRs, Contradictions and which Inventive Principles have been applied to achieve those solutions.

Using Triz To Design The Future Keyboard, Umakant Mishra

Umakant Mishra

A keyboard is the most common and widely used input device for a computer. Using the keyboard is often vital to interact with a computer. There are several aspects of a keyboard such as size, key layout, convenience and ergonomic features etc., which are continuously under improvement by keyboard designers and manufacturers. TRIZ is an efficient methodology in product designing. Using IFR and Trends we can well predict the directions of the future keyboards and using Contradictions and Principles we can overcome the current limitations. This article analyses the critical features of a keyboard, does a functional analysis, derives the …

An Ideal Computer Keyboard- A Case Study Of Applying Ideality On Keyboard Evolution, Umakant Mishra

Umakant Mishra

Any product or system moves towards its ideality. If we know the Ideal Final Result (IFR) it becomes easy to predict the future generation of the product or system. The author made a study of over 100 patents on computer keyboards. Each of these inventions tries to achieve some new feature or functionality. But what is the ultimate keyboard? This article makes an attempt to find the features of an Ideal Keyboard.

Inventions On Menu Interfacing For Gui Applications, A Triz Based Analysis, Part-1, Umakant Mishra

Umakant Mishra

During last two decades, the computer menu system has been improved from a text based multiple choice to highly adaptive, self organized menu system. This has been possible by hundreds of inventions. This article analyses 15 patents on Menu System from a TRIZ perspective to find out their IFRs and Contradictions. Besides we will also see what Inventive Principles have been applied to achieve those solutions.

Inventions On Computer Keyboard- A Triz Based Analysis, Umakant Mishra

Umakant Mishra

Every stage of evolution takes a product towards its ideality. This also happens in case of the Computer Keyboard. Today’s keyboards are outcome of hundreds of inventions in past. This article analyzes some interesting inventions on computer keyboard from TRIZ perspective. The inventions improve various aspects of computer keyboards like increasing operating (typing) efficiency, reducing size, improving ergonomic features and so on. This article was first published in TRIZ Journal (http://www.triz-journal.com/archives/2003/11/) in November 2003.

A Tabu Search Algorithm To Minimize The Makespan For The Unrelated Parallel Machines Scheduling Problem With Setup Times, Magdy Helal, Ghaith Rabadi, Ameer Al-Salem

Engineering Management & Systems Engineering Faculty Publications

In this paper we propose a tabu search implementation to solve the unrelated parallel machines scheduling problem with sequence- and machine- dependent setup times to minimize the schedules makespan. The problem is NP-hard and finding an optimal solution efficiently is unlikely. Therefore, heuristic techniques are more appropriate to find near-optimal solutions. The proposed tabu search algorithm uses two phases of perturbation schemes: the intra-machine perturbation, which optimizes the sequence of jobs on the machines, and the inter-machine perturbation, which balances the assignment of the jobs to the machines. We compare the proposed algorithm to an existing one that addressed the …

Efficient Scheduling For Sdmg Cioq Switches, Mei Yang, S. Q. Zheng

Electrical & Computer Engineering Faculty Research

Combined input and output queuing (CIOQ) switches are being considered as high-performance switch architectures due to their ability to achieve 100% throughput and perfectly emulate output queuing (OQ) switch performance with a small speedup factor S. To realize a speedup factor S, a conventional CIOQ switch requires the switching fabric and memories to operate S times faster than the line rate. In this paper, we propose to use a CIOQ switch with space-division multiplexing expansion and grouped input/output ports (SDMG CIOQ switch for short) to realize speedup while only requiring the switching fabric and memories to operate at the line …

Hiring Process For Software Developers That Identifies Both Cultural And Technical Fit, David E. Berry

Seton Hall University Dissertations and Theses (ETDs)

No abstract provided.

An Overview Of Mac Protocols With Directional Antennas In Wireless Ad Hoc Networks, Hong-Ning Dai, Kam-Wing Ng, Min-You Wu

Hong-Ning Dai

Although directional antennas have been used in mobile communications systems for quite a long time, realistic applications of directional or smart antennas in wireless ad hoc network have emerged just in recent years. Directional antennas provide numerous benefits, such as higher gains, increased transmission range and low interferences. Wireless medium access schemes play a crucial role in ensuring the efficient and fair sharing of wireless resources. Therefore there are many research work on mechanisms at the wireless medium access layer by using directional antennas. The new features of MAC with directional antennas can cause not only location dependent carrier sensing …

Mac Os X Forensics, Philip Craiger, Paul Burke

J. Philip Craiger, Ph.D.

Assessing Trace Evidence Left By Secure Deletion Programs, Paul Burke, Philip Craiger

J. Philip Craiger, Ph.D.