Mahalanobis Distance itself is just a mathematical calculation called generalized variance. The essential problem is a set of original data to construct Mahalanobis Space.

A new method for pattern recognition for hand writing letter is proposed in this article. The method is to construct Mahalanobis Space by using number of lines and the range of lines in each row and column. In the case of 32×32 cells in a square, we have 1024 digital response numbers. So, it is almost impossible to construct Mahalanobis space as we have to deal with 1024×1024 matrics. The method here needs to treat only smaller than 124×124 matrics. The method stated in this article may be also applied for many other pattern recognition as seen in the next article.

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In　the　design　of　alternating　current　circuits,　complex　numbers　are　commonly　used　to　describe　the values　of　the　circuit　elements　because　amplitude　and　phase　can　be　easily　determined. Root　mean　squares　(rms.)　have　traditionally　been　used　when　designing　AC　circuits.　By　using complex　numbers　in　parameter　design,　the　variability　of　both　amplitude　and　phase　of　the　output　can be　reduced.　Therefore,　a　system　whose　input　and　output　are　expressed　by　sine　waves,　should　use complex　numbers　to　conduct　parameter　designs.　By　doing　so,　we　would　expect　the　system　become more　stable　than　when　using　r.　m.　s. In　this　paper,　the　parameter　design　for　a　first-order　low　pass　filter　was　reported　to　show　the　efficiency　of　using　complex　numbers.　As　a　result　of　the　experiment,　of　the　stability　of　the　filter　was　improved　with　a　gain　of　as　high　as　3.79　dB.

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In　this　study,　a　Voltage　Controlled　Oscillator　(VCO),　used　in　our　Wireless　Communication　System,　was　designed　using　Quality　Engineering　Techniques　by　identifying　the　VCO's　basic　function. Traditionally,　during　the　design　stage,　the　VCO's　have　been　evaluated　by　measuring　the　frequency　selectivity　and　output　power　under　oscillating　conditions.　These　types　of　characteristics,　are　referred　to　as　"objective　quality　characteristics"　and　are　not　recommended　to　be　used. Instead,　the　basic　function　was　evaluated　in　a　non-oscillating　condition.　The　DC　signal　from　the power　supply　and　the　feed　back　AC　signal　are　supplied　to　the　transistor.　These　signals　were　put　to the　oscillation　circuit　and　produced　the　output　in　the　form　of　complex　numbers. The　results　were　analyzed　by　the　signal-to-noise　ratio　in　the　Hermitean　Form.　The　result　was　a stabilized　VCO　performance　and　a　high　reproducibility　of　the　improvements　and　conclusions　were confirmed.

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　Liquid　chromatographic/(LC)　analysis　is　an　effective　instrument　for　pharmaceutical　analysisand　pharmaceutical　science.　Various　methods　have　been　utilized　in　attempts　to　optimize　LC　analytical　conditions.　ln　order　to　obtain　a　high　degree　of　separation,　the　optimum　conditions　were　determined　by　the　use　of　dynamic　S/N　ratio　as　an　index　for　the　evaluation　of　the　separation　process.　An　L₁₈　orthogonal　array　was　used　in　this　experiment.　lt　was　demonstrated　that　S/N　ratio　was　an　appropriate　scale　to　indicate　the　separation　of　some　peaks　in　a　LC.　Also,　the　appropriate　types　of　S/N　ratio　to　show　the　degree　of　separation　in　a　LC　was　discussed.

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For　our　in-house　quality　engineering　education,　the　participants　conduct　parameter　design　workshop　using　a　KAMI-Copter　(Paper　helicopter)　as　an　example　to　enhance　their　better　understanding. In　the　initial　workshops,　the　generic　function　of　the　KAMI-Copter　was　discussed　and　clearly　defined. After　many　workshop　trials,　we　discussed　the　best　approach　to　measure　the　output,　selection　of controllable　and　uncontrollable　factors,　ways　of　combining　controllable　factor　levels　with　the　signal factor,　etc.　….　As　used　in　the　workshop　with　good　reproducibility　of　conclusions.

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