Optimum coding techniques for MST radars

The optimum coding technique for MST (mesosphere stratosphere troposphere) radars is that which gives the lowest possible sidelobes in practice and can be implemented without too much computing power. Coding techniques are described in Farley (1985). A technique mentioned briefly there but not fully developed and not in general use is discussed here. This is decoding by means of a filter which is not matched to the transmitted waveform, in order to reduce sidelobes below the level obtained with a matched filter. This is the first part of the technique discussed here; the second part consists of measuring the transmitted waveform and using it as the basis for the decoding filter, thus reducing errors due to imperfections in the transmitter. There are two limitations to this technique. The first is a small loss in signal to noise ratio (SNR), which usually is not significant. The second problem is related to incomplete information received at the lowest ranges. An appendix shows a technique for handling this problem. Finally, it is shown that the use of complementary codes on transmission and nonmatched decoding gives the lowest possible sidelobe level and the minimum loss in SNR due to mismatch

Decoding: Codes and hardware implementation

The MST radars vary considerably from one installation to the next in the type of hardware, operating schedule and associated personnel. Most such systems do not have the computing power to decode in software when the decoding must be performed for each received pulse, as is required for certain sets of phase codes. These sets provide the best signal to sidelobe ratio when operating at the minimum band length allowed by the bandwidth of the transmitter. The development of the hardware phase decoder, and the applicability of each to decoding MST radar signals are discussed. A new design for a decoder which is very inexpensive to build, easy to add to an existing system and is capable of decoding on each received pulse using codes with a band length as short as one microsecond is presented

Working Effectively with People with Learning Disabilities

This brochure on people with learning disabilities and the Americans with Disabilities Act (ADA) is one of a series on human resources practices and workplace accommodations for persons with disabilities edited by Susanne M. Bruyère, Ph.D., CRC, SPHR, Director, Program on Employment and Disability, School of Industrial and Labor Relations – Extension Division, Cornell University. Cornell University was funded in the early 1990’s by the U.S. Department of Education National Institute on Disability and Rehabilitation Research as a National Materials Development Project on the employment provisions (Title I) of the ADA (Grant #H133D10155). These updates, and the development of new brochures, have been funded by Cornell’s Program on Employment and Disability and the Pacific Disability and Business Technical Assistance Center, and there supporters

Grounding and making sense of agile software development.

The paper explores areas of strategic frameworks for sense-making, knowledge management and Grounded Theory methodologies to offer a rationalization of some aspects of agile software development. In a variety of projects where knowledge management form part of the solution we have begun to see activities and principles that closely correspond to many aspects of the wide family of agile development methods. We offer reflection on why as a community we are attracted to agile methods and consider why they work

Uncovering a KMSD approach from practice.

There is no credible methodology for knowledge management systems development (KMSD). We report on a KMSD approach that has emerged from an investigation based on action research and grounded theory into a number of business problems experienced by organizations. The KMSD approach is highly participatory, requiring full involvement of members of an organization. It has three interacting aspects: envisioning knowledge work behaviour, design of knowledge management system (KMS), and exploring technology options for supporting the KMS. In the first of these aspects, challenges and opportunities in an organization’s current situation are analysed and an improved situation is envisioned to expose knowledge concepts and their properties. In the second, a logical design of a KMS is produced using knowledge entities, knowledge flows and knowledge interfaces; the design is guided and constrained by an organization’s structure, culture, and resources. The third aspect is to do with introducing appropriate IT into KMS design, integrating organizational, social and technological aspects of the system. The paper describes this KMSD approach and how it emerged from both practical and theoretical investigation

The construction of a measurement of certain non-intellective determinants of academic success in college

Thesis (Ed.D.)--Boston Universit

Simultaneous fine structure observation of wind and temperature profiles by the Arecibo 430-MHz radar and in situ measurements

A simultaneous campaign of balloon and radar measurements took place on March 14 to 16, 1984, above the Arecibo 430-MHz radar. This radar was operating with a vertical resolution of 150 m following two antenna beam directions: 15 deg. from the zenith, respectively, in the N-S and E-W directions. The main results concerning the comparison between the flight and simultaneous radar measurements obtained on March 15, 1984 are analyzed. The radar return power profile (S/N ratio in dB) exhibits maxima which are generally well correlated with step-like structures in the potential temperature profile. These structures are generally considered as the consequence of the mixing processes induced by the turbulence. A good correlation appears in the altitude range 12.5 to 19 km between wind shears induced by a wave structure observed in the meridional wind and the radar echo power maxima. This wave structure is characterized by a vertical wavelength of about 2.5 km, and a period in the range 30 to 40 hours. These characteristics are deduced from the twice daily rawinsonde data launched from the San Juan Airport by the National Weather Service. These results pointed out an example of the interaction between wave and turbulence in the upper troposphere and lower stratosphere. Turbulent layers are observed at locations where wind shears related to an internal inertia-gravity wave are maxima

Towards a practical guide for developing knowledge management systems in small organizations.

There is no common method for developing KMS in organizations; practice is dominated by proprietary and ad hoc approaches and is often oriented towards information systems development. Currently KMS development (KMSD) omits the creation of KM cultures in unique organizational contexts, how to ‘operationalize’ knowledge, and how to support KMS with appropriate technologies. The paper provides practical insights via explanatory elements of a guide for a principled and useful KMSD approach, one which is adaptable for the complex situations of constantly and unpredictably changing environments and specific settings and needs of organizations. The guide’s concepts and approach have emerged from and been validated in practice by an inquiry into a number of problems experienced by particular organizations. For practitioners the paper presents insights into how to develop KMS that address organizational needs. For scholars our guide to a KMSD approach addresses calls in the literature for empirical research into the deployment of KMS and the role of IT in supporting KMS

A business-focused IT service model for Cloud

The hitherto limited interpretation of service as deployed in IT value creation and solutions implementation is perhaps a reason why so few IT projects are seen to have successful business outcomes. There are strong indications that the commonly used measures of quality and performance have never been adequate for complex services such as IT. As cloud-based technology changes the business and IT landscape it is important to consider how IT services will evolve and can be managed to become more business-focused. A services-based model for IT is described which has been developed from evidence gathered from business and IT and ideas from other sectors. Validated in the field, it is designed around the high value touch-points between business and IT and uses needs-based and experience-based measures for business alignment and service excellence. It is the first time that services have been identified formally as being necessary for business and IT alignment. This is of critical importance to businesses using cloud-based solutions and consistent with the service science notion of the co-creation of value