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  <xs:element id="intt_MinimumAmountRequiredForInvoicesReceived" abstract="false" name="MinimumAmountRequiredForInvoicesReceived" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="intt_ContingentConsiderationLiabilitiesMember" abstract="true" name="ContingentConsiderationLiabilitiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_RangeOfRemainingLeaseTermsInYearsYear" abstract="false" name="RangeOfRemainingLeaseTermsInYearsYear" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="intt_LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" abstract="false" name="LesseeOperatingLeaseLiabilityToBePaidAfterYearFour" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="intt_WarehouseAndOfficeSpaceMember" abstract="true" name="WarehouseAndOfficeSpaceMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_LesseeOperatingLeaseSquareFootageLeased" abstract="false" name="LesseeOperatingLeaseSquareFootageLeased" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:areaItemType"/>
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  <xs:element id="intt_AmendedLoanAgreementMember" abstract="true" name="AmendedLoanAgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_October2021AgreementMember" abstract="true" name="October2021AgreementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_DebtInstrumentLongtermFixedInterestRateDebtMember" abstract="true" name="DebtInstrumentLongtermFixedInterestRateDebtMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_DebtInstrumentShorttermVariableInterestRateDebtMember" abstract="true" name="DebtInstrumentShorttermVariableInterestRateDebtMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_MTBankMember" abstract="true" name="MTBankMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_TermNoteMember" abstract="true" name="TermNoteMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
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  <xs:element id="intt_DebtInstrumentAmortizationPeriod" abstract="false" name="DebtInstrumentAmortizationPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="intt_DebtInstrumentInterestRateInEventOfDefault" abstract="false" name="DebtInstrumentInterestRateInEventOfDefault" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:percentItemType"/>
  <xs:element id="intt_DebtInstrumentCovenantRatioOfConsolidatedFundedDebtToConsolidatedEBITDA" abstract="false" name="DebtInstrumentCovenantRatioOfConsolidatedFundedDebtToConsolidatedEBITDA" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="intt_DebtInstrumentCovenantFixedChargeCoverageRatio" abstract="false" name="DebtInstrumentCovenantFixedChargeCoverageRatio" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="xbrli:pureItemType"/>
  <xs:element id="intt_BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDebt" abstract="false" name="BusinessCombinationRecognizedIdentifiableAssetsAcquiredAndLiabilitiesAssumedDebt" nillable="true" xbrli:periodType="instant" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="intt_MtLaurelMember" abstract="true" name="MtLaurelMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_MansfieldMember" abstract="true" name="MansfieldMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_EndUserMember" abstract="true" name="EndUserMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_OemIntegratorsAndDistributorMember" abstract="true" name="OemIntegratorsAndDistributorMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_ThermalTestingProductsMember" abstract="true" name="ThermalTestingProductsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_ThermalProcessMember" abstract="true" name="ThermalProcessMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_SemiconductorProductionTestProductsMember" abstract="true" name="SemiconductorProductionTestProductsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_VideoImagingMember" abstract="true" name="VideoImagingMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_FlyingProbeAndIncircuitTestersMember" abstract="true" name="FlyingProbeAndIncircuitTestersMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_ServiceAndOtherProductsMember" abstract="true" name="ServiceAndOtherProductsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_SemiconductorMarketMember" abstract="true" name="SemiconductorMarketMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_AutomotiveMember" abstract="true" name="AutomotiveMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_DefenseAerospaceMember" abstract="true" name="DefenseAerospaceMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_IndustrialMarketMember" abstract="true" name="IndustrialMarketMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_LifeSciencesMember" abstract="true" name="LifeSciencesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_SecurityMember" abstract="true" name="SecurityMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_OtherMultiMarketsMember" abstract="true" name="OtherMultiMarketsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_CustomerAMember" abstract="true" name="CustomerAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_CustomerBMember" abstract="true" name="CustomerBMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_AccountsReceivableAllowanceForCreditLossForeignCurrencyTranslationImpact" abstract="false" name="AccountsReceivableAllowanceForCreditLossForeignCurrencyTranslationImpact" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="intt_The2023StockIncentivePlanMember" abstract="true" name="The2023StockIncentivePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
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  <xs:element id="intt_ShareBasedPaymentArrangementOptionExercisePriceRangeExpectedToVestWeightedAverageExercisePrice" abstract="false" name="ShareBasedPaymentArrangementOptionExercisePriceRangeExpectedToVestWeightedAverageExercisePrice" nillable="true" xbrli:periodType="instant" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="intt_ShareBasedPaymentArrangementOptionExercisePriceRangeExpectedToVestWeightedAverageRemainingContractualTerm" abstract="false" name="ShareBasedPaymentArrangementOptionExercisePriceRangeExpectedToVestWeightedAverageRemainingContractualTerm" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
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  <xs:element id="intt_VestingTiersDomain" abstract="true" name="VestingTiersDomain" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_VestingTierAMember" abstract="true" name="VestingTierAMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_VestingTierBMember" abstract="true" name="VestingTierBMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_VestingTierCMember" abstract="true" name="VestingTierCMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_VestingTierDMember" abstract="true" name="VestingTierDMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_VestingTierEMember" abstract="true" name="VestingTierEMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_PresidentAndChiefExecutiveOfficerMember" abstract="true" name="PresidentAndChiefExecutiveOfficerMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_ChiefExecutiveOfficerChiefFinancialOfficerAndOtherMembersOfSeniorManagementMember" abstract="true" name="ChiefExecutiveOfficerChiefFinancialOfficerAndOtherMembersOfSeniorManagementMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformanceVestingVolumeWeightedAveragePriceConsecutiveTradingDays" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardPerformanceVestingVolumeWeightedAveragePriceConsecutiveTradingDays" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="intt_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesSubjectToMarketConditions" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesSubjectToMarketConditions" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:sharesItemType"/>
  <xs:element id="intt_ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesSubjectToMarketConditionsPricePerShare" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardSharesSubjectToMarketConditionsPricePerShare" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:perShareItemType"/>
  <xs:element id="intt_ShareBasedCompensationArrangementByShareBasedPaymentAwardGrantDateFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardGrantDateFairValue" nillable="true" xbrli:periodType="instant" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="intt_ChiefExecutiveOfficerChiefFinancialOfficerAndDivisionPresidentsMember" abstract="true" name="ChiefExecutiveOfficerChiefFinancialOfficerAndDivisionPresidentsMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_PresidentOfProcessTechnologiesMember" abstract="true" name="PresidentOfProcessTechnologiesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_PerformanceBasedRestrictedStockGrantedMarch162026Member" abstract="true" name="PerformanceBasedRestrictedStockGrantedMarch162026Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_PerformanceBasedRestrictedStockGrantedMarch172025Member" abstract="true" name="PerformanceBasedRestrictedStockGrantedMarch172025Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_PerformanceBasedRestrictedStockGrantedMarch62024Member" abstract="true" name="PerformanceBasedRestrictedStockGrantedMarch62024Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_PerformanceBasedRestrictedStockGrantedJanuary162024Member" abstract="true" name="PerformanceBasedRestrictedStockGrantedJanuary162024Member" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_ShareBasedPaymentAwardGrantDateOneMember" abstract="true" name="ShareBasedPaymentAwardGrantDateOneMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_ShareBasedPaymentAwardGrantDateTwoMember" abstract="true" name="ShareBasedPaymentAwardGrantDateTwoMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_ShareBasedPaymentAwardGrantDateThreeMember" abstract="true" name="ShareBasedPaymentAwardGrantDateThreeMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantedFairValue" abstract="false" name="ShareBasedCompensationArrangementByShareBasedPaymentAwardEquityInstrumentsOtherThanOptionsGrantedFairValue" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
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  <xs:element id="intt_EmployeeStockPurchasePlanMember" abstract="true" name="EmployeeStockPurchasePlanMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_PayrollTaxesAndPayrollRelatedMember" abstract="true" name="PayrollTaxesAndPayrollRelatedMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_ProfessionalFeesMember" abstract="true" name="ProfessionalFeesMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_RetentionMember" abstract="true" name="RetentionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_CEOTransitionMember" abstract="true" name="CEOTransitionMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_VideologyConsolidationMember" abstract="true" name="VideologyConsolidationMember" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="dtr-types:domainItemType"/>
  <xs:element id="intt_DefinedContributionPlanMaximumAnnualEmployerMatchingContributionPerEmployeeAmount" abstract="false" name="DefinedContributionPlanMaximumAnnualEmployerMatchingContributionPerEmployeeAmount" nillable="true" xbrli:periodType="duration" xbrli:balance="debit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
  <xs:element id="intt_DefinedContributionPlanEmployerMatchingContributionVestingPeriod" abstract="false" name="DefinedContributionPlanEmployerMatchingContributionVestingPeriod" nillable="true" xbrli:periodType="duration" substitutionGroup="xbrli:item" type="xbrli:durationItemType"/>
  <xs:element id="intt_OperatingIncomeLossAdjusted" abstract="false" name="OperatingIncomeLossAdjusted" nillable="true" xbrli:periodType="duration" xbrli:balance="credit" substitutionGroup="xbrli:item" type="xbrli:monetaryItemType"/>
</xs:schema>
