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  <xsd:element abstract="true" id="naii_statement-statement-note-c-property-and-equipment-tables" name="statement-statement-note-c-property-and-equipment-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-d-leases-lease-cash-flow-information-details" name="statement-statement-note-d-leases-lease-cash-flow-information-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-d-leases-tables" name="statement-statement-note-d-leases-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-e-other-comprehensive-income-loss-schedule-of-other-comprehensive-income-loss-details" name="statement-statement-note-e-other-comprehensive-income-loss-schedule-of-other-comprehensive-income-loss-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-e-other-comprehensive-income-loss-tables" name="statement-statement-note-e-other-comprehensive-income-loss-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-f-debt-future-debt-payments-details" name="statement-statement-note-f-debt-future-debt-payments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-f-debt-tables" name="statement-statement-note-f-debt-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-g-income-taxes-geographical-breakdown-of-income-before-income-taxes-details" name="statement-statement-note-g-income-taxes-geographical-breakdown-of-income-before-income-taxes-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-g-income-taxes-net-deferred-tax-assets-and-deferred-tax-liabilities-details" name="statement-statement-note-g-income-taxes-net-deferred-tax-assets-and-deferred-tax-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-g-income-taxes-provision-for-income-taxes-details" name="statement-statement-note-g-income-taxes-provision-for-income-taxes-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-g-income-taxes-reconciliation-of-income-tax-provision-details" name="statement-statement-note-g-income-taxes-reconciliation-of-income-tax-provision-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-g-income-taxes-schedule-of-income-taxes-paid-details" name="statement-statement-note-g-income-taxes-schedule-of-income-taxes-paid-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-g-income-taxes-tables" name="statement-statement-note-g-income-taxes-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-h-employee-benefit-plans-benefit-payments-expected-to-be-paid-details" name="statement-statement-note-h-employee-benefit-plans-benefit-payments-expected-to-be-paid-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-h-employee-benefit-plans-components-included-in-defined-benefit-plans-net-periodic-benefit-expense-details" name="statement-statement-note-h-employee-benefit-plans-components-included-in-defined-benefit-plans-net-periodic-benefit-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-h-employee-benefit-plans-components-included-in-defined-benefit-plans-net-periodic-benefit-expense-details-parentheticals" name="statement-statement-note-h-employee-benefit-plans-components-included-in-defined-benefit-plans-net-periodic-benefit-expense-details-parentheticals" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-h-employee-benefit-plans-defined-benefit-pension-plans-funded-status-and-amount-recognized-details" name="statement-statement-note-h-employee-benefit-plans-defined-benefit-pension-plans-funded-status-and-amount-recognized-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-h-employee-benefit-plans-defined-benefit-pension-plans-funded-status-and-amount-recognized-details-parentheticals" name="statement-statement-note-h-employee-benefit-plans-defined-benefit-pension-plans-funded-status-and-amount-recognized-details-parentheticals" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-h-employee-benefit-plans-defined-benefit-plans-weighted-average-asset-association-and-weighted-average-target-allocation-details" name="statement-statement-note-h-employee-benefit-plans-defined-benefit-plans-weighted-average-asset-association-and-weighted-average-target-allocation-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-h-employee-benefit-plans-fair-values-by-asset-category-of-defined-benefit-pension-plan-details" name="statement-statement-note-h-employee-benefit-plans-fair-values-by-asset-category-of-defined-benefit-pension-plan-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-h-employee-benefit-plans-summary-of-changes-in-plan-assets-and-benefit-obligation-details" name="statement-statement-note-h-employee-benefit-plans-summary-of-changes-in-plan-assets-and-benefit-obligation-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-h-employee-benefit-plans-summary-of-changes-in-plan-assets-and-benefit-obligation-details-parentheticals" name="statement-statement-note-h-employee-benefit-plans-summary-of-changes-in-plan-assets-and-benefit-obligation-details-parentheticals" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-h-employee-benefit-plans-tables" name="statement-statement-note-h-employee-benefit-plans-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-h-employee-benefit-plans-weightedaverage-rates-used-in-determining-defined-benefit-pension-plans-net-pension-costs-details" name="statement-statement-note-h-employee-benefit-plans-weightedaverage-rates-used-in-determining-defined-benefit-pension-plans-net-pension-costs-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-i-stockholders-equity-restricted-stock-details" name="statement-statement-note-i-stockholders-equity-restricted-stock-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-i-stockholders-equity-tables" name="statement-statement-note-i-stockholders-equity-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-i-stockholders-equity-treasury-stock-repurchases-details" name="statement-statement-note-i-stockholders-equity-treasury-stock-repurchases-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-j-commitments-minimum-rental-commitments-details" name="statement-statement-note-j-commitments-minimum-rental-commitments-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-j-commitments-tables" name="statement-statement-note-j-commitments-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-k-economic-dependency-substantial-net-purchase-from-certain-suppliers-details" name="statement-statement-note-k-economic-dependency-substantial-net-purchase-from-certain-suppliers-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-k-economic-dependency-substantial-net-sales-to-certain-customers-details" name="statement-statement-note-k-economic-dependency-substantial-net-sales-to-certain-customers-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-k-economic-dependency-tables" name="statement-statement-note-k-economic-dependency-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-n-segment-information-capital-expenditures-by-geographical-region-details" name="statement-statement-note-n-segment-information-capital-expenditures-by-geographical-region-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-n-segment-information-longlived-assets-by-geographical-region-details" name="statement-statement-note-n-segment-information-longlived-assets-by-geographical-region-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-n-segment-information-net-sales-by-geographic-region-details" name="statement-statement-note-n-segment-information-net-sales-by-geographic-region-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-n-segment-information-operating-results-by-business-segment-details" name="statement-statement-note-n-segment-information-operating-results-by-business-segment-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-n-segment-information-tables" name="statement-statement-note-n-segment-information-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-note-n-segment-information-total-assets-by-geographical-region-details" name="statement-statement-note-n-segment-information-total-assets-by-geographical-region-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="naii_statement-statement-significant-accounting-policies-policies" name="statement-statement-significant-accounting-policies-policies" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
</xsd:schema>
