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The recently introduced detected-jump correcting quantum codes are capable of stabilizing qubit-systems against spontaneous decay processes arising from couplings to statistically independent reservoirs. These embedded quantum codes exploit classical information about which qubit has emitted spontaneously and correspond to an active error-correcting code embedded in a passive error-correcting code. The construction of a family of one detected jump-error correcting quantum codes is shown and the optimal redundancy, encoding and recovery as well as general properties of detected jump-error correcting quantum codes are discussed. By the use of design theory multiple jump-error correcting quantum codes can be constructed. The performance of one jump-error correcting quantum codes under non-ideal conditions is studied numerically by simulating a quantum memory and Grover's algorithm.

A new class of error-correcting quantum codes is introduced capable of stabilizing qubits against spontaneous decay arising from couplings to statistically independent reservoirs. These quantum codes are based on the idea of using an embedded quantum code and exploiting the classical information available about which qubit has been affected by the environment. They are immediately relevant for quantum computation and information processing using arrays of trapped ions or nuclear spins. Interesting relations between these quantum codes and basic notions of design theory are established.

The document suggests some new modeling approcaches for equal employment opportunity (EEO) planning. Previous manpower planning models of the Office of Civilian Manpower Management have utilized multi-period Markoff processes embedded in goal programing (multiple objective) models. These are here extended to EEO plans directed to changing the mix of employees over time. At each point in the planning interval, the organization is taken as given (for example, in terms of the probabilities for promotion, transfer, etc.) when formulating manpower programs. Over time, however, these organization processes are submitted to planned changes which alter the probabilities of occurrence for these events. The Merit Promotion System is preserved and other controls are also imposed explicity for the exercise of managerial discretion. The focus here is on an ordinary (absolute value) formulation of objectives and a numerical illustration is supplied with differing weights for each of the indicated classes of objectives. Other types of objectives are briefly discussed, along with different approaches to problems of validation and, subsequently, implementation in a U. S. Navy context. (Author/EC)