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  <xsd:element id="intt_AllowanceForDoubtfulAccountsReceivableForeignCurrencyTranslation" name="AllowanceForDoubtfulAccountsReceivableForeignCurrencyTranslation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_AmbrellEuropeanOperationsConsolidationMember" name="AmbrellEuropeanOperationsConsolidationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_AmbrellMember" name="AmbrellMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_AssetMember" name="AssetMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_AutomobileLeasesMember" name="AutomobileLeasesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_BasisOfPresentationAndUseOfEstimatesPolicyTextBlock" name="BasisOfPresentationAndUseOfEstimatesPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_BusinessCombinationContingentConsiderationArrangementsPaymentOfEarnoutForPriorYearAcquisitionOperatingActivities" name="BusinessCombinationContingentConsiderationArrangementsPaymentOfEarnoutForPriorYearAcquisitionOperatingActivities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_CashChargesMember" name="CashChargesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_CityOfRochesterAndStateOfNewYorkMember" name="CityOfRochesterAndStateOfNewYorkMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_ContingentLiabilityRepaymentOfStateAndLocalGrantFundsReceived" name="ContingentLiabilityRepaymentOfStateAndLocalGrantFundsReceived" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="intt_ContingentLiabilityRepaymentOfStateAndLocalGrantFundsReceivedPolicyPolicyTextBlock" name="ContingentLiabilityRepaymentOfStateAndLocalGrantFundsReceivedPolicyPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_CostsRelatedToSublettingFacility" name="CostsRelatedToSublettingFacility" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="intt_CostsRelatedToSublettingTheFremontCAFacility" name="CostsRelatedToSublettingTheFremontCAFacility" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="intt_CovenantFutureAmountReceivable" name="CovenantFutureAmountReceivable" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="intt_CurrentLiabilitiesTableTextBlock" name="CurrentLiabilitiesTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_DecreaseInOperatingLeaseLiabilitiesAndRightOfUseAssetsNonCash" name="DecreaseInOperatingLeaseLiabilitiesAndRightOfUseAssetsNonCash" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_DefenseAerospaceMember" name="DefenseAerospaceMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_DeferredGrantProceeds" name="DeferredGrantProceeds" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="intt_DeferredTaxAssetsAcquisitionCosts" name="DeferredTaxAssetsAcquisitionCosts" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="intt_DeferredTaxAssetsOperatingLeases" name="DeferredTaxAssetsOperatingLeases" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="instant"/>
  <xsd:element id="intt_DeferredTaxLiabilitiesRightOfUseAssets" name="DeferredTaxLiabilitiesRightOfUseAssets" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="instant"/>
  <xsd:element id="intt_DefinedContributionPlanEmployerMatchingContributionVestingPeriod" name="DefinedContributionPlanEmployerMatchingContributionVestingPeriod" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_DefinedContributionPlanMaximumAnnualEmployerMatchingContributionPerEmplyeeAmount" name="DefinedContributionPlanMaximumAnnualEmployerMatchingContributionPerEmplyeeAmount" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="intt_DiscountedCashFlowsDiscountRate" name="DiscountedCashFlowsDiscountRate" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_DocumentAndEntityInformation" name="DocumentAndEntityInformation" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_EMSMember" name="EMSMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_EMSSegmentRestructuringAndFacilityConsolidationMember" name="EMSSegmentRestructuringAndFacilityConsolidationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_EmployeesMember" name="EmployeesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_EndUserMember" name="EndUserMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_ExecutiveManagementChangesMember" name="ExecutiveManagementChangesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_FacilitySizeReductionMember" name="FacilitySizeReductionMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_ForfeitureOfUnvestedSharesOfRestrictedStockInANoncashInvestingAndFinancingActivities" name="ForfeitureOfUnvestedSharesOfRestrictedStockInANoncashInvestingAndFinancingActivities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="intt_GoodwillIntangibleAndLongLivedAssetsPolicyTextBlock" name="GoodwillIntangibleAndLongLivedAssetsPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_HeadcountReductionsAndEmployeeRelocationMember" name="HeadcountReductionsAndEmployeeRelocationMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_IncomeTaxReconciliationDeemedDividendFromForeignSubsidiaries" name="IncomeTaxReconciliationDeemedDividendFromForeignSubsidiaries" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="intt_IncomeTaxReconciliationEffectsOfNetOperatingLossAndTaxCreditCarryforwards" name="IncomeTaxReconciliationEffectsOfNetOperatingLossAndTaxCreditCarryforwards" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="intt_IncomeTaxReconciliationIncomeTaxReconciliationGlobalIntangibleLowTaxedIncome" name="IncomeTaxReconciliationIncomeTaxReconciliationGlobalIntangibleLowTaxedIncome" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="intt_IncomeTaxReconciliationSection250ForeignDerivedIntangibleIncomeDeduction" name="IncomeTaxReconciliationSection250ForeignDerivedIntangibleIncomeDeduction" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="intt_IncreaseDecreaseInAccruedProfessionalFees" name="IncreaseDecreaseInAccruedProfessionalFees" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="intt_IncreaseDecreaseInAccruedSalesCommission" name="IncreaseDecreaseInAccruedSalesCommission" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="intt_IncreaseDecreaseInOperatingLeaseLiabilities" name="IncreaseDecreaseInOperatingLeaseLiabilities" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="intt_IncreaseInOperatingLeaseLiabilitiesAndRightofuseAssetsNonCash" name="IncreaseInOperatingLeaseLiabilitiesAndRightofuseAssetsNonCash" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_IndependentDirectorsMember" name="IndependentDirectorsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_IndustrialMarketMember" name="IndustrialMarketMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_LeaseAgreementAmbrellsNetherlandsFacilityMember" name="LeaseAgreementAmbrellsNetherlandsFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_LeaseAgreementAmbrellsUKMember" name="LeaseAgreementAmbrellsUKMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_LeaseAgreementEMSFacilityInFremontCaliforniaMember" name="LeaseAgreementEMSFacilityInFremontCaliforniaMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_LeaseAgreementEmsFacilityInMtLaurelNewJerseyMember" name="LeaseAgreementEmsFacilityInMtLaurelNewJerseyMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_LeaseForFacilityInMansfieldMassachusettsMember" name="LeaseForFacilityInMansfieldMassachusettsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_MTMember" name="MTMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_MansfieldMassachusettsMember" name="MansfieldMassachusettsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_MansfieldMember" name="MansfieldMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_MtLaurelMember" name="MtLaurelMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_NonCashChargesMember" name="NonCashChargesMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_NoteToFinancialStatementDetailsTextual" name="NoteToFinancialStatementDetailsTextual" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_NotesToFinancialStatements" name="NotesToFinancialStatements" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_NotesToFinancialStatementsAbstract" name="NotesToFinancialStatementsAbstract" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_NumberOfMajorCustomers" name="NumberOfMajorCustomers" nillable="true" substitutionGroup="xbrli:item" type="xbrli:integerItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_OEMAndIntegratorsMember" name="OEMAndIntegratorsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_OperatingLeaseIncreaseInArea" name="OperatingLeaseIncreaseInArea" nillable="true" substitutionGroup="xbrli:item" type="num:areaItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_OperatingLeaseRemainingLeaseTerm" name="OperatingLeaseRemainingLeaseTerm" nillable="true" substitutionGroup="xbrli:item" type="xbrli:durationItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_OtherMultiMarketsMember" name="OtherMultiMarketsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_OtherRestructuringActionsMember" name="OtherRestructuringActionsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_PaymentsForStockRepurchasedBrokerFees" name="PaymentsForStockRepurchasedBrokerFees" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element id="intt_ProceedsFromPaycheckProtectionProgramUnderCaresAct" name="ProceedsFromPaycheckProtectionProgramUnderCaresAct" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="intt_ProceedsFromSaleOfMachineryAndEquipmentNetOfGain" name="ProceedsFromSaleOfMachineryAndEquipmentNetOfGain" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_RestrictedStockVestingInFourYearsMember" name="RestrictedStockVestingInFourYearsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_RestrictedStockVestingInThreeYearsMember" name="RestrictedStockVestingInThreeYearsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_RestructuringAndOtherCharges" name="RestructuringAndOtherCharges" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="intt_RestructuringAndOtherChargesPolicyTextBlock" name="RestructuringAndOtherChargesPolicyTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_ScheduleOfCarryingValueOfFinitelivedIntangibleAssetsTableTextBlock" name="ScheduleOfCarryingValueOfFinitelivedIntangibleAssetsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_ScheduleOfChangesInAllowanceForDoubtfulAccountsReceivableTableTextBlock" name="ScheduleOfChangesInAllowanceForDoubtfulAccountsReceivableTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_ScheduleOfIntangibleAssetsTableTextBlock" name="ScheduleOfIntangibleAssetsTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_ScheduleOfOutstandingLettersOfCreditTableTextBlock" name="ScheduleOfOutstandingLettersOfCreditTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_SemiconductorMarketMember" name="SemiconductorMarketMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_SemiconductorProductionTestProductsMember" name="SemiconductorProductionTestProductsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_ServiceAndOtherProductsMember" name="ServiceAndOtherProductsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_SeveranceAndOtherOneTimeTerminationBenefits" name="SeveranceAndOtherOneTimeTerminationBenefits" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_SeveranceAndOtherOnetimeTerminationBenefitsMember" name="SeveranceAndOtherOnetimeTerminationBenefitsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_ShareBasedCompensationAwardTrancheFourMember" name="ShareBasedCompensationAwardTrancheFourMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentageLowerRange" name="SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentageLowerRange" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentageUpperRange" name="SharebasedCompensationArrangementBySharebasedPaymentAwardAwardVestingRightsPercentageUpperRange" nillable="true" substitutionGroup="xbrli:item" type="num:percentItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantedFairValue" name="SharebasedCompensationArrangementBySharebasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantedFairValue" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="debit" xbrli:periodType="duration"/>
  <xsd:element id="intt_SharebasedPaymentArrangementReversalOfExpense" name="SharebasedPaymentArrangementReversalOfExpense" nillable="true" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType" xbrli:balance="credit" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_SigmaMember" name="SigmaMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_StockPlan2014Member" name="StockPlan2014Member" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_StockRepurchasePlanTextBlock" name="StockRepurchasePlanTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_SublettingCostsOfTheFremontCaFacilityMember" name="SublettingCostsOfTheFremontCaFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_SublettingCostsOfTheMansfieldMAFacilityMember" name="SublettingCostsOfTheMansfieldMAFacilityMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_SupplementalCashFlowInfomationLesseeTableTextBlock" name="SupplementalCashFlowInfomationLesseeTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_TelecommunicationsMarketMember" name="TelecommunicationsMarketMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_TexasInstrumentsIncorporatedMember" name="TexasInstrumentsIncorporatedMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_The401KPlanMember" name="The401KPlanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_TheAmbrellPlanMember" name="TheAmbrellPlanMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_ThermalProcessMember" name="ThermalProcessMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_ThermalTestingProductsMember" name="ThermalTestingProductsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_ThermonicsMember" name="ThermonicsMember" nillable="true" substitutionGroup="xbrli:item" type="nonnum:domainItemType" xbrli:periodType="duration"/>
  <xsd:element id="intt_ValuationAllowancesAndReservesTableTextBlock" name="ValuationAllowancesAndReservesTableTextBlock" nillable="true" substitutionGroup="xbrli:item" type="nonnum:textBlockItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-10-debt-outstanding-letters-of-credit-details" name="statement-statement-note-10-debt-outstanding-letters-of-credit-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-10-debt-tables" name="statement-statement-note-10-debt-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-11-income-taxes-deferred-tax-assets-and-liabilities-details" name="statement-statement-note-11-income-taxes-deferred-tax-assets-and-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-11-income-taxes-earnings-before-income-taxes-details" name="statement-statement-note-11-income-taxes-earnings-before-income-taxes-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-11-income-taxes-effective-tax-rate-analysis-and-reconciliation-of-expected-statutory-rate-details" name="statement-statement-note-11-income-taxes-effective-tax-rate-analysis-and-reconciliation-of-expected-statutory-rate-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-11-income-taxes-income-tax-expense-benefit-details" name="statement-statement-note-11-income-taxes-income-tax-expense-benefit-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-11-income-taxes-tables" name="statement-statement-note-11-income-taxes-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-13-stockbased-compensation-plan-allocation-of-sharebased-compensation-expense-details" name="statement-statement-note-13-stockbased-compensation-plan-allocation-of-sharebased-compensation-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-13-stockbased-compensation-plan-stock-option-activity-details" name="statement-statement-note-13-stockbased-compensation-plan-stock-option-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-13-stockbased-compensation-plan-stock-option-activity-details-parentheticals" name="statement-statement-note-13-stockbased-compensation-plan-stock-option-activity-details-parentheticals" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-13-stockbased-compensation-plan-stock-options-valuation-assumptions-details" name="statement-statement-note-13-stockbased-compensation-plan-stock-options-valuation-assumptions-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-13-stockbased-compensation-plan-tables" name="statement-statement-note-13-stockbased-compensation-plan-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-13-stockbased-compensation-plan-unvested-stock-activity-details" name="statement-statement-note-13-stockbased-compensation-plan-unvested-stock-activity-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-16-segment-information-identifiable-assets-details" name="statement-statement-note-16-segment-information-identifiable-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-16-segment-information-longlived-assets-by-geographical-area-details" name="statement-statement-note-16-segment-information-longlived-assets-by-geographical-area-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-16-segment-information-net-revenue-from-unaffiliated-customers-details" name="statement-statement-note-16-segment-information-net-revenue-from-unaffiliated-customers-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-16-segment-information-segment-information-details" name="statement-statement-note-16-segment-information-segment-information-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-16-segment-information-tables" name="statement-statement-note-16-segment-information-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-17-quarterly-consolidated-financial-data-unaudited-quarterly-consolidated-financial-data-details" name="statement-statement-note-17-quarterly-consolidated-financial-data-unaudited-quarterly-consolidated-financial-data-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-17-quarterly-consolidated-financial-data-unaudited-tables" name="statement-statement-note-17-quarterly-consolidated-financial-data-unaudited-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-2-summary-of-significant-accounting-policies-tables" name="statement-statement-note-2-summary-of-significant-accounting-policies-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-2-summary-of-significant-accounting-policies-weighted-average-common-shares-details" name="statement-statement-note-2-summary-of-significant-accounting-policies-weighted-average-common-shares-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-3-restructuring-and-other-charges-changes-in-accrued-restructuring-details" name="statement-statement-note-3-restructuring-and-other-charges-changes-in-accrued-restructuring-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-3-restructuring-and-other-charges-restructuring-and-related-costs-details" name="statement-statement-note-3-restructuring-and-other-charges-restructuring-and-related-costs-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-3-restructuring-and-other-charges-tables" name="statement-statement-note-3-restructuring-and-other-charges-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-4-goodwill-and-intangible-assets-changes-in-the-amount-of-the-carrying-value-of-intangible-assets-details" name="statement-statement-note-4-goodwill-and-intangible-assets-changes-in-the-amount-of-the-carrying-value-of-intangible-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-4-goodwill-and-intangible-assets-component-of-goodwill-details" name="statement-statement-note-4-goodwill-and-intangible-assets-component-of-goodwill-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-4-goodwill-and-intangible-assets-future-amortization-expense-details" name="statement-statement-note-4-goodwill-and-intangible-assets-future-amortization-expense-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-4-goodwill-and-intangible-assets-intangible-assets-details" name="statement-statement-note-4-goodwill-and-intangible-assets-intangible-assets-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-4-goodwill-and-intangible-assets-tables" name="statement-statement-note-4-goodwill-and-intangible-assets-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-5-revenue-from-contracts-with-customers-changes-in-allowance-for-doubtful-accounts-details" name="statement-statement-note-5-revenue-from-contracts-with-customers-changes-in-allowance-for-doubtful-accounts-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-5-revenue-from-contracts-with-customers-disaggregation-of-revenues-details" name="statement-statement-note-5-revenue-from-contracts-with-customers-disaggregation-of-revenues-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-5-revenue-from-contracts-with-customers-tables" name="statement-statement-note-5-revenue-from-contracts-with-customers-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-7-inventories-inventories-held-details" name="statement-statement-note-7-inventories-inventories-held-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-7-inventories-tables" name="statement-statement-note-7-inventories-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-8-leases-lease-costs-details" name="statement-statement-note-8-leases-lease-costs-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-8-leases-lease-modifications-details" name="statement-statement-note-8-leases-lease-modifications-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-8-leases-maturities-of-lease-liabilities-details" name="statement-statement-note-8-leases-maturities-of-lease-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-8-leases-tables" name="statement-statement-note-8-leases-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-9-other-current-liabilities-other-current-liabilities-details" name="statement-statement-note-9-other-current-liabilities-other-current-liabilities-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-note-9-other-current-liabilities-tables" name="statement-statement-note-9-other-current-liabilities-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-schedule-ii-valuation-and-qualifying-accounts-tables" name="statement-statement-schedule-ii-valuation-and-qualifying-accounts-tables" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_statement-statement-schedule-ii-valuation-and-qualifying-accounts-valuation-and-qualifying-accounts-details" name="statement-statement-schedule-ii-valuation-and-qualifying-accounts-valuation-and-qualifying-accounts-details" nillable="true" substitutionGroup="xbrli:item" type="xbrli:stringItemType" xbrli:periodType="duration"/>
  <xsd:element abstract="true" id="intt_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>
