Key processing with control vectors

A method is presented for controlling cryptographic key usage based on control vectors. Each cryptographic key has an associated control vector that defines the permitted uses of the key within the cryptographic system. At key generation, the control vector is cryptographically coupled to the key by way of a special encryption process. Each encrypted key and control vector are stored and distributed within the cryptographic system as a single token. Decryption of a key requires respecification of the control vector. As part of the decryption process, the cryptographic hardware verifies that the requested use of the key is authorized by the control vector. This article focuses mainly on the use of control vectors in cryptosystems based on the Data Encryption Algorithm.     

Transformation of the EFQM approach from business towards operations excellence

The purpose of this paper is to provide an enabler-based approach for a supervised self-assessment of operations excellence (OsE). Based on the latest approaches of excellence in operations from the literature as well as on the philosophy of the EFQM model, an OsE working definition was developed. In contrast to operational excellence (OE), which deals exclusively with the optimization of result driven processes, OsE promotes the enhancement of operation-specific enablers and linked results. The evaluation of crucial cause–effect relationships of relevant enabler and result criteria supports the determination of a company’s capability to achieve sustainability and excellence in terms of its operations. To foster a methodical integration of OsE in organizations, a phase model for a systematic assessment process was designed and verified with 24 companies in the Austrian machinery and metalware industries.     

Reconstruction of nonlinearly distorted signals with regularized inverse characteristics

A signal distorted by a system having static, invertible, nonlinear characteristics can be exactly restored in the absence of noise. In this case, the inverse of the characteristics can be used. When noise is superimposed to the distorted signal, the inverse characteristics may not be proper because the noise is strongly amplified. This noise has to be suppressed in the reconstructed signal, which can be accomplished only at the price of bias. This article presents a method to compensate the effect of static nonlinearities in the presence of noise. This method is based on Tikhonov's regularization operators and provides a compromise between noisy and biased estimates.     

Past,present and future activities in food hygiene of the Veterinary Public Health Unit (VPH) of the World Health Organization

The paper contains a review of the activities in the field of food hygiene performed by the Veterinary Public Health Unit of WHO in close collaboration with other divisions and programmes of the Organization. It gives a general understanding about the purpose and objectives of such activities in the past and present, and near future. The paper mentions the most important achievements which were reached by the Organization in meat and milk hygiene, fish and shellfish hygiene, surveillance of foodborne diseases, microbiological specifications for foods, food virology education and training in food hygiene and elaboration of a strategy on prevention and control of foodborne diseases due to food of animal origin. The paper contains 44 references, the majority of which are still available at the World Health Organization.     

Impaired limb position sense after stroke: a quantitative test for clinical use

OBJECTIVE: A quantitative measure of wrist position sense was developed to advance clinical measurement of proprioceptive limb sensibility after stroke. Test-retest reliability, normative standards, and ability to discriminate impaired and unimpaired performance were investigated. DESIGN: Retest reliability was assessed over three sessions, and a matched-pairs study compared stroke and unimpaired subjects. Both wrists were tested, in counterbalanced order. SETTING: Patients were tested in hospital-based rehabilitation units. PATIENTS AND OTHER PARTICIPANTS: Reliability was investigated on a consecutive sample of 35 adult stroke patients with a range of proprioceptive discrimination abilities and no evidence of neglect. A consecutive sample of 50 stroke patients and convenience sample of 50 healthy volunteers, matched for age, sex, and hand dominance, were tested in the normative-discriminative study. Age and sex were representative of the adult stroke population. MAIN OUTCOME MEASURES: The test required matching of imposed wrist positions using a pointer aligned with the axis of movement and a protractor scale. RESULTS: The test was reliable (r = .88 and .92) and observed changes of 8 degrees can be interpreted, with 95% confidence, as genuine. Scores of healthy volunteers ranged from 3.1 degrees to 10.9 degrees average error. The criterion of impairment was conservatively defined as 11 degrees (+/-4.8 degrees) average error. Impaired and unimpaired performance were well differentiated. CONCLUSIONS: Clinicians can confidently and quantitatively sample one aspect of proprioceptive sensibility in stroke patients using the wrist position sense test. Development of tests on other joints using the present approach is supported by our findings.     

How to test graphical user interfaces

An approach for automatically testing GUIs in the MATLAB environment has been proposed. We developed a software tool that tests GUIs by simulating the user through an action recorder. We proposed a heuristic test procedure: providing random input to GUI, but guiding the randomness with predefined weights assigned to the user controls. The weights change during the testing process, as the controls are activated. The errors are collected for later investigation.     

ATM cell encryption and key update synchronization

This paper presents a data compaction/randomization based approach as a mode of block encryption for ATM (Asynchronous Transfer Mode) cells. The presented approach converts a plaintext into pseudo‐random plaintext before ciphering to conceal patterns in the plaintext. The underlying idea behind this scheme is the Shannon's principles of “confusion” and “diffusion” which involve breaking dependencies and introducing as much randomness as possible into the ciphertext. In this scheme, confusion and diffusion are introduced into the system by first compressing the ATM cell payload and then spreading a continuously changing random data over the entire content of the cell. As a mode of operation for block ciphering, this scheme offers the following attractive features:(i) plaintext patterns are pseudo‐randomized and chained with ciphertext (thereby, preventing against “dictionary”, “known plaintext”, and “statistical analysis” attacks), (ii) it is self‐synchronizing, (iii) cell loss has no additional negative effect, (iv) no IV (Initialization Vector) storage is required, (v) it is encryption‐algorithm independent, (vi) there is no cell‐to‐cell dependency (no feedback from previous cells), and (vii) it is highly scalable (i.e., cells from the same stream can be ciphered and deciphered in parallel). This paper also presents a secure mechanism for in‐band synchronization of encryption/decryption key updates using a “marker‐cell” that is carried within the data channel. An important aspect of both the above mechanisms is that they do not require any changes to the ATM cell header or ATM infrastructure. This revised version was published online in June 2006 with corrections to the Cover Date.     

Outbreak of adenovirus 35 pneumonia among adult residents and staff of a chronic care psychiatric facility

Outbreaks of acute respiratory disease caused by adenovirus are rarely documented in civilian populations, and adenovirus 35 is an uncommon serotype best recognized as a cause of serious disease in immunocompromised patients. An outbreak of adenovirus 35 pneumonia among residents and staff of a chronic care psychiatric facility was investigated. Fourteen (26%) of 53 residents and 4 (2%) of approximately 200 staff had radiographically confirmed pneumonia. Thirteen (93%) of 14 residents with pneumonia were hospitalized, 5 (36%) required mechanical ventilation, and 1 (7%) died. One staff member was hospitalized. Adenovirus infection was diagnosed in 17 (94%) persons with pneumonia by culture or serology and was confirmed as adenovirus 35 infection in 8 persons. Residents with pneumonia had resided at the facility longer than other residents. Chronic illness was not a risk factor for severe disease. Crowding and poor hygienic behaviors probably facilitated transmission among residents.     

Decision-Aided Tracking Loops for Channels with Phase Jitter and Intersymbol Interference

The theory of decision-aided carrier tracking loops as developed by Lindsey and Simon is extended to include the effects of intersymbol interference. A major theoretical result is the solution of the Fokker-Planck equation for the probability density function (pdf) of the phase error for a first-order tracking loop. This function is used to average upper and lower bounds on the demodulator error rate so that an estimate of the overall system error rate may be obtained. The modulation technique analyzed is double-sideband-pulse-amplitude pulse-amplitude modulation. Curves are presented which display the threshold performance of the system error rate at low modulation index.     

Demand assignment for light-route TDMA

With the fluctuating inter-nodal traffic levels that characterize light-route networks, demand assignment (DA) provides the means of increasing the system's effective capacity. This paper focuses on the application of DA in light-route TDMA, and proposes a control architecture that is well-suited to service of heterogeneous traffic. The major advantage of the proposed architecture is its benefit from both the efficient resource management typical of centralized schemes, and the shorter response times of distributed schemes. The impact of the assignment algorithm on the grade of service to heterogeneous populations, and the difficulty in quantifying this impact are also addressed. Results from analytical and simulation models illustrating resource utilization are presented.