Abstract: A method and apparatus are provided for word synchronization with large coding distance and fault tolerance for a partial-response maximum-likelihood (PRML) data channel in a direct access storage device (DASD). A Viterbi detector receives equalized PR4 samples including a predefined word synchronization pattern. The Viterbi detector is a dedicated detector optimized for detecting the predefined word synchronization pattern. The Viterbi detector includes a two-state Viterbi trellis and a word synchronization detector for the two-state Viterbi trellis. The predefined word synchronization pattern includes only even length magnets. The predefined word synchronization pattern is a repetition code including pairs of ones and pairs of zeros and includes multiple pattern match sequences. The Viterbi detector is optimized with branches removed from the Viterbi trellis, thus increasing coding distance.

Abstract: A method and apparatus are provided for thermal asperity recovery for word sync detection in data channels. A word sync field contains a plurality of word sync patterns. A word sync detector receives a read signal of the word sync field. The word sync detector identifies a first subset of the plurality of word sync patterns and starts a customer data read. When the word sync detector fails to identify the first subset of the plurality of word sync patterns, the read signal of the word sync field is received again. Then the word sync detector identifies a second predefined subset of the plurality of word sync patterns and starts a customer data read. A single word sync field is used instead of the conventional dual word sync fields required for each sector. The second predefined subset of the plurality of word sync patterns is smaller than the first subset. For example, when the first subset is defined as 4 of 8, the second predefined subset is 2 of 8.

Abstract: A method and apparatus are provided for word synchronization with large coding distance and fault tolerance for a partial-response maximum-likelihood (PRML) data channel in a direct access storage device (DASD). A Viterbi detector receives equalized PR4 samples including a predefined word synchronization pattern. The Viterbi detector is a dedicated detector optimized for detecting the predefined word synchronization pattern. The Viterbi detector includes a two-state Viterbi trellis and a word synchronization detector for the two-state Viterbi trellis. The predefined word synchronization pattern includes only even length magnets. The predefined word synchronization pattern is a repetition code including pairs of ones and pairs of zeros and includes multiple pattern match sequences. The Viterbi detector is optimized with branches removed from the Viterbi trellis, thus increasing coding distance.

Abstract: The present disclosure relates to an inbred non-human transgenic animal having a multimeric nuclear hormone receptor, comprising a thyroid hormone receptor subunit and a nuclear hormone receptor subunit, wherein either or both the thyroid hormone receptor subunit and a nuclear hormone receptor subunits are mutated such that expression of said multimeric nuclear hormone receptor results in a measurable phenotype. The disclosure also contemplates methods of making inbred non-human transgenic animals. Methods of using the disclosed inbred non-human transgenic animals as models for various diseases and for screening small molecules that are determined to be efficacious in the treatment of such diseases are also disclosed.

Abstract: A phase locked loop unlock detector is provided for a data detection channel in a direct access storage device (DASD). The phase locked loop unlock detector includes a counter for generating a threshold reference relative to a reference signal. An unlock window generator is coupled to the counter for generating an unlock window signal. An unlock error detector is coupled to the unlock window generator for comparing a variable frequency signal with the unlock window signal.

Abstract: A data encoding method and apparatus are provided for implementing a predefined rate code, such as a 16/17 rate code for a data detection channel in a direct access storage device. A binary data stream is received and sequential symbols of the received binary data stream are identified. Sequential alternate symbols of the binary data stream are encoded into first codewords. Sequential alternate other symbols are encoded into second codewords. The alternating first and second codewords are sequentially combined. For a rate 16/17 rate code, the first codewords include 9-bit codewords and the second codewords include 8-bit codewords. The second 8-bit codewords are either raw symbols of the received binary data stream or remapped symbols of the received binary data stream. All likely error events are limited to within three consecutive bytes in a user data stream with a 16/17 rate code of the preferred embodiment.