accurate inventory planning & stock control

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Mengenai Akurasi perhitungan Stock Barang,rumus Persediaan Stock barang yang aman untuk Perusahaan manufacture, Adanya penjelasan mengenai Sales Demand berguna bagi para marketing.

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    Accurate Inventory PlanningAccurate Inventory Planning

    ococ on roon ro

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    TrainerProfile Ir.Imanadi Lulusdari ITSTeknik Mesin di tahun 1993

    perusahaan nasional dan MultiNationalCompanyuntuk fokus bisnis:SoftSkill,procurement/purchasing,warehouse&logistic,PPICdan Qualitysejak

    tahun 2008.

    Imanadi mempunyai pengalaman selama 15tahun dalam bidang

    manufacturing,

    Warehouse

    &

    Inventory

    Control,

    Quality

    Management

    S stem ContinuousIm rovementPro ram De artmentIm rovement

    Program,Training&PeopleDevelopment di beberapa perusahaan MNC

    seperti AT&T(USA),Sinoca Electronics(Taiwan)PirelliCables(Italia)&

    Geomed (Jerman).

    Selain sebagai publicspeaker/trainer,Imanadi juga merupakan anggota teamtrainerdari BBMI BrainBoosterManagementIndonesia,sebuah institusi

    yangfokus dalam pengembangan &peningkatan kinerja otak yangberpusat

    di Jakarta.

    2 214:39:29

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    Peserta diharapkan akan memahami:

    Inventory

    costMengukur performanceinventory

    Berapa banyak inventoryyangdiperlukan?

    Forecastingdemand

    Menentukan Safetystock

    C cle countin

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    Menurut APICS(AssociationforOperation

    Stockatau itemyangdigunakan untukmendukung productiondan customer

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    DefinisiInventor

    mendukungproduksi(rawmaterials&

    WIPitems),mendukungaktifitas

    (maintenance,re air&o eratin supplies)&customerservice(FG&

    .

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    6

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    nce

    ntoryBala

    Inve

    Waktu

    ungs nven ory a an menurun era an engan

    waktu 7

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    Untuk antisipasi:demandyangnaik turun,faktor musiman,promosi,keterlambatan supplierdll

    Safetystock:bila terjadi deviasi/penyimpangan antara forecast

    Lotsizeinventory:lotsizeuntuk produksi maupun minimumorder t dari su lier

    Transportationinventory:inventoryintransit

    Hed e inventor : untuk meneta kan har a an fluktuasi

    Buffer:cadangan bila demandnya naik sedangkan kapasitastetap

    8

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    Biaya Inventory

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    Inventor Costs.

    2. Carryingcosts/biaya menyimpan

    3. Orderingcosts/biaya mengorder

    .

    5. Capacityrelatedcosts/biaya kapasitas

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    Item

    Costs9

    pabrikgudang.

    er r ar :9 Productcost/harga barang

    9 Customsdutiescost/bea masuk

    9 Directmaterial,directlabor,andfactoryoverhead/biaya material,

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    Carr in

    Costs/Bia a Men im an

    Capitalcosts:uang yg mati dlm stock

    Storagecosts:Ruang,karyawan &peralatan

    Riskcosts risiko:Obsolescence usan damage/rusak,expired,insurance/asuransi,

    Makinban ak inventor costn a akan

    meningkat

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    Hitunglah costpertahun,

    1,000,000,capitalcost6%,

    biaya risiko 10%

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    Costyg muncul untuk memesan ke vendor

    meliputi: Productioncontrol(PPIC&purchasing)

    Setupandteardown/biaya setup

    Lostcapacity/kehilangan kapasitas Purchaseorder

    191414:39 14

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    on oHitun lah rata2 bia a utk memesan satu order

    bila :

    . , ,

    rata2costpersetupRp 200,000

    jumlah order20,000xperthn

    201514:39 j15

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    stock

    Bila kebutuhan selama leadtimemelebihistock,terjadilah stockoutyang

    menyebabkan:

    Backordercosts/biaya penundaan Lostsalescosts/biaya kehilangan sales

    Lostcustomercosts/bia a kehilan an

    customers

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    Ca acitRelated

    Costs

    Biaya krn perubahan schedule&qtypro u si

    Overtime/undertime

    Hiring/rekrut

    LayoffTraining

    Shiftpremiums/tunjangan shift

    Dpt dihindari dengan menyamakan qtyprod.perhari

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    InventoryHoldingCosts

    CategoryCost as a

    % of Inventory Value

    Housingcosts(buildingrent,depreciation,

    operatingcost,taxes,insurance)6%

    (3 - 10%)

    Materialhandlingcosts(equipment,lease

    ordepreciation,power,operatingcost)(1 - 3.5%)

    3%

    Investmentcosts(borrowingcosts,taxes,

    (3 - 5%)

    11%(6 - 24%)

    Pilferage,scrap,andobsolescence

    3%

    (2 - 5%)

    Overall carrying cost 26%18

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    Surplus/ObsoleteInventory

    Bila inventory yang disiapkan bagi customer/produksimelebihi demand akan ter adi sur lus

    Pada satu saat surplus tidak dipakai lagi karena demand tidakada, kondisi ini disebut obsolete

    Inventory

    Demand

    urpus

    obsolete

    1 2 3 4 5 6 7 8 9 10 11 12 13 14

    Quarter 1 Quarter 2 Quarter 3 Quarter 4

    15

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    Sur lus Obsolete

    apa a as engan me a u an:

    9Preventive: pencegahan penambahan kembali stockyang sudah surplus, monitor dengan ketat master

    scheduling & MRP

    9Identifikasi transaksi barangbarang surplus

    9Disposal, kalau sudah tidak bisa dipakai lagi

    45

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    1021

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    Profitdapat ditingkatkan dengan:

    Meningkatkan customerservice

    Menurunkan roductioncosts

    Menurunkan inventoryinvestment

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    Materials

    Management

    &Profits

    Direct a or

    Bervariasi dengan volumeyangdijual Overhead

    Tidak bervariasi dengan qtyyangdijual

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    Dollars %ofSales

    Sales

    Revenue $1,000,000 100

    CostofGoodsSold

    DirectMaterial $500,000 50

    DirectLabour $200,000 20

    Overhead 200,000 20

    TotalCostofGoodsSold $900,000 90

    GrossProfit $100,000 10

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    Dollars %ofSales

    Sales

    Revenue $1,000,000 100

    CostofGoodsSold

    DirectMaterial $500,000 50

    DirectLabour $200,000 20

    Overhead 200,000 20

    TotalCostofGoodsSold $900,000 90

    GrossProfit $100,000 10

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    Men uran i Materials10%&Laborsebesar 5%Dollars %ofSales

    SalesRevenue $1,000,000 100

    DirectMaterial $450,000 45

    DirectLabour $190,000 19

    ,

    TotalCostofGoodsSold $840,000 84

    GrossProfit $160,000 16

    Profittelah meningkat 60%

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    MaterialsManagement

    ro ts

    Dollars %

    of

    Sales

    SalesRevenue $1,200,000 100

    DirectMaterial $600,000 50

    DirectLabour $240,000 20

    ,

    TotalCostofGoodsSold $1,040,000 87

    ,

    Salesharus meningkat 20%

    Bagaimana Menurut anda Situasi ini ?

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    . .

    Directlabor=$700,000 ,

    Factoryoverhead=$700,000

    enera a m n s ra veexpense=

    $300,000

    Berapa GrossMargin&NetIncome?

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    Inventor

    Turnover Bagaimana mengukur performanceinventory? engan meg tung turnoverrat onya ya tu:

    InventoryTurnsRatio=Harga pokok penjualan setahun/rata2inventorydalam setahun

    Contoh:Jika COGS(harga pokok penjualan )sebesar $1juta dollars, ,

    InventoryTurnovernya =$1,000,000/$500,000 = 2 Bisa juga dengan cara:sales/rata2inventory

    Atau jumlah hari atau minggu inventoryave inv/cogs(intimebasis) Makinpanjang jumlah hari inventory,putarannya makin kecil,

    artin a uan kita terbenam dalam inventor

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    latihan Inventor

    Turns

    $24juta &rata2inventorysebesar $6juta?.

    inventoryturnsditingkatkan menjadi 12kaliper

    c.Jika biaya menyimpan inventorysebesar 25%dari

    ,

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    inventory$2juta:

    berapa inventoryturnover?

    berapa inventoryrata2bila inventory

    turnovernya ditingkatkan menjadi 10x

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    Ri ht uantit

    Righttime

    Rightplace

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    HighLevelEnterpriseResourcePlanningModelHighLevelEnterpriseResourcePlanningModel

    CCFF

    StrategicStrategic

    PlanningPlanning

    22--10 Years10 Years

    Forecast OnlyForecast Only

    AA

    PPAA

    RR

    EE

    CC

    BusinessBusinessPlanningPlanning

    AnnuallyAnnually

    Forecast OnlyForecast Only

    Sales&OperationsSales&Operations

    II

    TT

    YY

    AA

    SS

    TT

    II

    MonthlyMonthly

    Forecast OnlyForecast Only

    ResourceResource

    PlanningPlanning

    MasterMaster

    PP

    LL

    AA

    NN

    GG

    &&WeeklyWeekly RoughRough--cutcut

    CapacityCapacity

    Sc e u ingSc e u ingNNNN

    II

    NN

    DD

    EE

    MM DailyDaily

    OrdersOrders

    ann nann n

    CapacityCapacity

    RequirementsRequirements

    &Scheduling&Scheduling GGAA

    NNDD

    Orders OnlyOrders Only PlanningPlanning

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    mendatang , ,

    market

    ,

    besarnyainventory,servicelevelcustomer,

    budgetuntukmasing2departmentdalam

    menunjangsalesforecast,rencanainvestasimesin,mould,dies,tambahankaryawan

    (permanen outsource)

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    utama untuk merencanakan inventoryuntukroduksi urchasin & ersia an roduk s are

    partmaupun subassembly

    S&OPdilakukan untuk roduct rou in .Karenaforecastingdalam groupingakan lebih akurat

    dibandingkan masing2SKU/item

    OutputS&OPadalah productionplan,inventoryplan&salesplan

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    PrePre--S&OP andS&OP and

    may be combinedmay be combined

    into one meetinginto one meeting

    Output S&OP:Output S&OP:1.1.Sales planSales plan

    2.2.Inventory planInventory plan3.3.Production PlanProduction Plan

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    T eBas c P rT eBas c P r

    pastplanpastplantotoactualactual

    performanceperformance

    InventoryPlan=PlannedOpening

    Inventory+PlannedProduction

    PlannedSales

    ActualInventory =Opening

    Inventory+ActualProduction

    ActualSales

    14:39 37

    S&OP i CS&OP i C F ti l PF ti l P

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    S&OPisaCrossS&OPisaCrossFunctionalProcessFunctionalProcess

    Marketing &Marketing &EngineeringEngineering

    S&OP ProcessS&OP Process

    DefinitionDefinitionuu

    DemandDemand

    ap aap a

    MasterMaster

    AvailabilityAvailability

    FinanceFinanceHumanHuman

    ResourcesResources

    c e uec e ueBusinessBusiness

    PlanPlan

    MaterialsMaterialsOperationsOperations

    Must champion the processMust champion the process

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    ApaYangDijawabS&OP?

    S&OPmenyeimbangkan demand&capacitydenganmenjawab 6pertanyaan penting sbb:

    1.Bera a ban ak demanduntuk roductfamil ?

    2.Berapa banyak inventoryyangkita miliki?

    3.Berapa banyak inventoryyangharus ditambahkan?

    4.Kapan inventorydibutuhkan?

    5. Apakahkapasitas tersedia untuk mendapatkan inventorytambahan?

    6.Apakahrencana dalam S&OPsesuai dengan sasaran businessplan?

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    Masterschedulingadalah proses

    proses S&OPmenjadi jadwal untuk

    prioritas &qty

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    Material

    Re uirement

    Plan

    MRP

    Menentukankebutuhanmaterialuntukmenunjang

    MPS(masterproductionschedule)

    Berapabanyak

    qty,

    kapan

    dibutuhkan,

    kapan

    PO

    di

    release

    Inputnya:BOM(billofmaterial),MPS,planningdata

    supp ier,minimum

    or er

    qty,

    ea

    time,

    scrap

    ratio

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    InputMRP

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    Contoh Bill

    of

    Material

    BOMSinglelevelBOM

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    ContohMRP

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    Kunci Sukses MRP

    Inventoryakurasi:harus 98 100%agartidak terjadie urangan e e an mater a yangmen ng at an cost

    BOM (billofmaterial)akurasi:harus ada yangmengauditBOM(designengineer)agarselalu update

    Manufacturin & urchasin leadtimeakurasi:leadtimeyangtidak akurat meningkatkan cost(kapasitas,material/ekses inventory,expeditingcost,freightcost)

    Standardlotsize:harus di updatekarena berpengaruhterhadap inventory.Lotsizemanufacturingsangatber antun ada setu time.Karena itu ban ak com an membuat leanprogram

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    InventoryPlanningZone

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    Perubahan Planning

    5 Customersmembatalkan orders.

    ustomersmenam a mengurang qtyor er

    5 Customersmengubah tanggal pengiriman lebih awal kadang2

    5 Customersmeminta produk yangberbeda dari yangdi order

    SKU berbeda

    5 Produksi mengalami masalah kualitas atau qtyproduksi tidaktercapai

    5 Mesin produksi mengalami masalah/kerusakan

    pera or produksi a sen

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    Inventory

    stock

    records

    tidak akurat

    Supplier

    shortages.

    Supplierterlambat kirim material

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    ,

    sudahfirm.Perubahandalamperiodeiniakanmeningkatkancost.Biasanyazone1adalah1minggu

    Zone2:informasiyangmasukberupacustomerorder

    danforecast.Perubahandalamzoneinida atdilakukandengantradeoffdenganSKUyanglain

    .

    Perubahandalamperiodeinitidakakanmeningkatkancost

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    Adalah suatu teknik optimisasi inventory

    Dengan adanya visibilitydari levelinventory,

    su liersda at memelihara &men isikembali (replenish)inventorysecara siklus.

    Kepemilikan inventoryberada di supplierwalaupun materialberada di cusomter

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    Setelah customermen unakan

    inventorytsb,baru akan ditagihkan

    Kondisi VMIdapat diterapkan

    asalkan ada winwinsituationbagi

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    Mengurangi levelinventory

    inventory(carryingcost)

    engurang stoc outs

    Mengurangi overheadcost

    mengelola inventory

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    Meningkatkan cashtocashcycle

    (pembayaran materialsmendekati

    tanggal pemakaian)

    Menin katkan o ortunit cost uaninventorydapat digunakan untuk

    kesem atan an lain

    Mengurangi kerusakan inventory

    ,

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    Mengurangi gangguan urgent

    Mendapatkan kontrak jangka panjang

    Demandyangdapat diprediksi

    engan aProfitmarginmeningkat

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    OrderPoint Penting untuk diingat:

    r er q y e ap

    9Order intervals (waktunya) bervariasi9Jika demand atau lead time berubah order pointharus diubah

    Order Pointh

    and

    Safety StockUnits

    o

    LeadTime

    Time

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    Contoh OrderPointFormulaeman = un s per wee

    Lead time = 4 weeks Safet stock = 100 units

    OP = DDLT + SS

    = 100 (4) + 100

    = 500

    80

    OrderPoint

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    = crew ar o.

    Re-Order point = 100 units

    On On

    01 500 500

    02 500 400 100

    04 400 100 0 100

    05 500 600 600

    81

    Demand Forecastin

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    DemandForecastin

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    Adalah perkiraan kebutuhan dimasa depan

    Dapat ditentukan secara matematis melalui

    a au me a u u

    informal atau melalui kedua teknik tsb.

    14:39 60

    Sia a an membuat

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    Sia a an membuat

    ForecastDemand?

    Ataukah

    Marketing

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    ForecastDemand

    Itsonlastsession

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    group,groupofexperts,thinktanks,research.

    Quant tat ve: er asar an per tungan

    matematis datahistoris.Eg;movingaverage,

    seasona

    n exes

    exponent a

    smoot ng.

    14:39 63

    m rm r f r inf r in

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    m rm r f r inf r in

    Intrinsic:berdasarkan datainternalperusahaan

    bunga bank,pertumbuhan ekonomi dll

    Umumnya companybanyak menggunakan

    gabungan kedua sumber tsb

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    Demanddapat datang dari berbagai

    sumber spt:

    Consumers

    Customers

    Referrers

    Dealers

    Distributors

    Interplant Service arts

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    Trend(keatas/kebawah,linear/nonlinear)

    Cyclicality/adanya siklus

    Seasonality/musiman

    Randomvariations

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    Demand vs waktu14:39 67

    Pola Demand

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    Pola Demand

    Stableversusd namic

    Stabledemandmemiliki bentuk/trendyang

    Dynamicdemandcenderung erratic

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    Prinsi dasar Forecastin

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    Prinsi dasar Forecastin

    Forecastsbiasanyasalah demandsangat

    bergantungpadabanyakvarabel.Sulituntuk

    Forecastsakanlebihakuratuntuk:

    Family/groupproduct

    Tiapforecastharusadaestimasierrornya

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    TeknikTeknik uantitativeuantitative

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    TeknikTeknik uantitativeuantitative

    ExponentialsmoothingExponentialsmoothing RegressionanalysisRegressionanalysis

    AdaptivesmoothingAdaptivesmoothing

    GraphicalmethodsGraphicalmethods

    LifecyclemodelingLifecyclemodeling

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    Akan mempengaruhi kemampuan customeruntukmembeli roduk asa an kita tawarkan.E :bun a

    bankberpengaruh pada kemampuan membeli

    rumah,kendaraan

    Pyramidforecasting:makin tinggi suatu itemdalam

    hirarki,akurasi nya akan semakin tinggi pula.

    Tingkatforecast

    yang

    paling

    efektif adalah padalevelproductfamilyatau productsubfamilylevel.

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    Manfaatnya

    Teknik sederhana &mudah dihitung

    Dapat digunakan untuk filteroutrandomvariation

    Periode yanglebih panjang akan memberikan gambaranyang e i a us

    Keterbatasan

    Jika terjadi trend,agak sulit mendeteksi

    Movingaveragesterlambat mengikuti trend

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    forecastlama

    updatingitemforecasts.

    Al haadalah bobot an diberikan ada actualdemand

    Cukup baik bekerja untuk demandyangcukup konstan

    Cukup baik untuk forecastjangka pendek

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    Newforecast= xactualdemand+(1 )xoldforecast=oldforecast+ (actualdemand

    oldforecast)

    Oldforecast=160,actual=200, =0.1

    New

    forecast

    =

    160+(0.1x(200

    160))=164 Oldforecast=160,actual=200, =0.8 = =.

    Makindekat dengan 1.0,makin responsiveforecastn a den an demandterakhir.

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    Pengaruhnilai

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    Figure 8.5 Exponential forecast where trend exists

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    latihansmoothin forecast

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    Month Actual demand Forecast demand

    1 260

    3 225

    4 245

    5 250

    6

    Hitunglah forecast untuk bulan 1 sampai 6, bila alfa adalah 0,2 dan forecast padabulan ke 1 sebesar 240

    14:39 76

    QualitativeTechni ues

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    Expertopinion

    FocusgroupHistoricalanalogy Panelconsensus

    7714:39 77

    ExternalFactors(Extrinsic)

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    Competition

    Newcustomers

    Plansofmajorcustomers

    Governmentpolicies

    Regulatoryconcerns

    Economicconditions

    Environmentalissues

    WeatherconditionsGlobaltrends

    14:39 78

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    (seasonal),kita dapat menghitung seasonal

    SeasonalIndex=(rata2demandutk

    per o e s verage eman u semuaperiode)

    Indexdapat digunakan sebagai pengali

    untuk forecastke depan

    14:39 79

    contoh Seasonalit

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    14:39 80

    contoh Seasonalit

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    Darigambar tsb:tidak ada trendtapi ada faktor

    musiman.

    Rata2demandtiap quarter/kwartal adalah 100unit

    Maka seasonalindexmasing2kwartal sbb:

    Kwartal 1=128/100=1.28

    Kwartal 2=102/100=1.02

    Kwartal 3=

    75/100

    =

    0.75

    Kwartal 4=95/100=0.95

    14:39 81

    contoh Seasonalit

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    tahunkedepansebesar420unit

    Jawab:forecastrata2perkwartalditahundepan=

    420 4=

    105

    Forecastkwartal1=1.28x105=134.4unit

    = =

    Forecastkwartal3=0.75x105=78.75unit . .

    14:39 82

    latihanseasonalindex

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    Month Average Demand Seasonal index

    J anuary 30

    e ruary

    March 85

    April 110

    May 125

    J une 245

    August 135

    September 110

    cto e

    November 60

    Desember 30

    Hitungseasonalindexuntukmasing2bulan14:39 83

    forecast error

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    Adalahperbedaanantaraacutaldemand&.

    Errorterjadidalam2hal:Bias&random

    variation

    Bias ter adi bila kumulative actual demand

    bervariasidarikumulativeforecast

    14:39 84

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    14:39 85

    F r ca t tan a ia ran m variati n

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    14:39 86

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    14:39 87

    ABCInventoryControl

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    pengawasan.

    price/unit

    Berdasarkan Pareto:

    Kelas A,20%dari itemtotal,kontribusi nilai uangnya sebesar 80%.

    Kelas B,30%dari itemtotal,kontribusi nilai uangnya sebesar 15%dari Rp pemakaian.

    Kelas C,50%dari itemtotal,kontribusi nilai uangnya sebesar 5%dariRp pemakaian.

    258814:39 88

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    Nilai Item dalam

    Rp

    ,Usage x price/unitUsage x price/unit

    L M N O P Q R S T UInventory Items

    14:39 89

    ABCAnalysis PenerapanPrinsipParetos80/20

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    Nilai Item

    dalam Rp

    Nilai item disusundari yang terbesar

    hingga terkecil

    O S L N R Q M P U T

    Inventory Items14:39 90

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    -100

    -90-

    dalam Rp

    Value-70

    -60

    -50-40

    -30

    -20

    -10

    O S L N R Q M P U T

    Inventory Items14:39 91

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    a ue o

    Items % of total-100-a ue

    -80-70

    -60

    Class A 20%Class A 20%

    of items 80%of items 80% -50-40-30

    of valueof value Class C 50%of items; 5% of

    value

    -20

    -10Class B 30%

    of items; 15%of value

    O S L N R Q M P U T

    Inventory Items14:39 92

    No Item Unit dipakai/bulan Harga (Rp)

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    No Item Unit dipakai/bulan Harga (Rp)

    1 1100 2

    2 600 40

    3 100 4

    4 1300 1

    5 100 60

    6 10 25

    7 100 2

    8 1500 2

    9 200 2

    10 500 1

    14:39 93

    ContohContoh ABCABC

    dipakai/bulan

    harga

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    dipakai/bulan harga

    1 1100 2 2200

    2 600 40 24000

    3 100 4 400

    4 1300 1 1300

    5 100 60 6000

    6 10 25 250

    7 100 2 200

    9 200 2 400

    10 500 1 500

    Total 5510 38250

    14:39 94

    NoItem Unit Harga (Rp) Pemakaian x Akumulasi Persentase Kelas

    n

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    n

    2 600 40 24000 24000 62.75% A

    5 100 60 6000 30000 78.43% A

    8 1500 2 3000 33000 86.27% B

    1 1100 2 2200 35200 92.03% B

    4 1300 1 1300 36500 95.42% B

    10 500 1 500 37000 96.73% C

    3 100 4 400 37400 97.78% C

    .

    6 10 25 250 38050 99.48% C

    Total 5510 3825014:39 95

    ClassAItems

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    Itemini umumnya memiliki nilai strategis dalam perusahaan.Karena valuen a tin i

    Penting untuk menjaga informasi itemini:

    Berapa yangkita miliki

    Dimana ada dalam sistem

    Apa yg sedang di order&kapan deliverynya.

    Forecastingsales

    Akurasi stockdi gudang

    Berapa inventoryturnovernya?

    Berapa safetystocknya?

    Contoh di perusahaan anda??

    3396

    14:39 96

    ClassCitems

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    Slowmovingitem

    Nilainya rendah,komoditi denganvolumebesar &menyita tempat

    Dasarnya adalah jangan sampaikehabisan stock

    Biasanya stockdihitung tahunan,kadang2dengan cara menimbang

    untuk mengontrol stockminimum&pengisian kembali (vendormanagednventory ons nyas

    3497

    14:39 97

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    Biasanya pembelian langsung ditangani

    perusahaan

    Biasanya stocktakedilakukan 24x/thn

    98

    14:39 98

    Metode Mengawasi Inventory

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    Class A Class B Class C

    High consumption Moderate value Low value

    Very strict control Medium control Loose control

    Nil Safety Stock Low safety stocks High safety stock

    Daily Deliveries Weekly/ Monthly Bulk/ Quarterl

    Multi-sources Few sources Max.- 2 sources

    Accurate forecasts Estimates Guestimmates

    Central storage Storage in each plant Site storage

    . .

    99

    ABCuntuk sparepart

    V E D C t l ABC VED combine control

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    V E D Control: ABC VEDcombinecontrol

    V: Vital items

    E: Essential/penting items

    D: Desirable/diinginkan items

    The basis of control is the criticality of the item

    Vital - indicating that m/c cant run without V Item.

    Essential - m/c can run but without parameters as such efficiency,,.

    Desirable- m/c can run but factor of safety, industrial formalities cantbe satisfied (e.g. - wearing ear protection aid)

    100

    ABCuntuk sparepart

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    ABC VEDcombine control

    ABCClassification

    VED Classification

    V items E items D items

    A itemsRegular stocks with

    constant controlMedium stock No Stock

    B items Medium Stock Medium Stock Very low Stocks

    C items High Stock Medium Stock Low Stock

    101

    u u v

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    F:FastmovingItems

    N:NormalmovingItemsS:SlowmovingItems

    D:Deaditems

    ThebasisofcontrolistheUsa erate

    102

    SummaryofSelectiveControlTechniques

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    Selective ControlTechnique

    Basis of classification Chief Use

    ABC Consumption value Controlling RM, WIP and components

    Determinin the inventor level of s arer ca y o em

    parts

    XYZ Value of item in storage Reviewing the inventories & other uses

    FNSD Consumption rate of item Controlling obsolescence

    103

    IRA Pernahkah anda Mendengarnya

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    14:39:30 104

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    a a arus a ura

    Caramana yangterbaik dalammelakukan auditrecords

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    ar e nven ory

    No. Count Record

    2 99 100

    3 101 100

    Total 295 300 Accuracy=295/300Or98.3%

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    Part Shelf Inventor Accurac

    No. Count Record Calculation

    1 95 100 95%

    2 99 100 99%

    3 101 100 99%

    Total 295 300Accuracy=Avg.ofthethree

    .

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    .

    2. Planning(Unitswithtolerances)3. Production(Unitsw/otolerances)

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    No. Cost Count Record Unit $$$$

    1 $10 95 100 5 50

    2 $ 30 99 100 1 30

    3 $ 80 101 100 + 1 + 80

    Total 295 300 0NoFinancial

    Ad ustment

    100%Accurate

    P t T l Sh lf I t Withi O t id

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    Part Toler Shelf Inventory Within Outside

    No. ance Count Record Tolerance Tolerance

    1 7% 95 100 X2 3% 99 100 X

    3 0% 101 100 X

    Accuracy=2/3

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    Part S e Inventory

    No.

    Count Record

    2 99 100

    3 101 100

    WrongWrong

    WrongWrong

    Total 295 300

    Accuracy=0/3

    Or0%

    CaraMengukurInventoryRecordAccuracy

    measurementMaximum+/ 5%

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    Inventory

    inventory

    12004 100 90 +/- 5% Miss

    17809 200 202 +/- 1% Hit

    19876 100 99 +/- 0% Miss

    +- ss

    98706 100 104 +- 5% Hi

    14:39:31 113

    Ph i l I t C ti h

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    Ph sicalInventor Countin han amembetulkan recordssaja

    Masalah!

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    FINANCIAL!

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    Menghabiskan

    Melelahkan

    en m u an etidakakuratan

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    Sample Counts

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    SampleCounts

    Investigasi Penyebab

    Causecodesassi ned Dilakuan oleh personel yang

    terlatih

    Correctiveactionim lemented

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    .

    2. Longlastingaccuracy

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    ,

    Tidak membetulkan recordyangada Tidak mengidentifikasi masalah

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    a a pen e a an

    yangspesifik untukmen ng a an

    Sebuah metoda

    berbasis 5Langkah

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    InvestigateCauses

    4 RootCauseAnalysis

    SustaintheImprovement

    MeasureandRecordAccuracy3BeBrutallyHonest

    CountSample2CounteachweekUntilperfect

    SelectControlSample1

    degreeofproblems;

    NoTolerances

    ControlGroupCounting

    Tentukan itemdalam grupSejumlah kecil iteminventory

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    j y

    Yangmewakili keseluruhan inventory

    Purchased/manufacturedpartsemyang esar ec

    Rawmaterial,components,finishedgoods

    A B dan C items

    Fastmaupun slowmoving

    Posisi negatif dalam sistem

    Posisi nol dalam sistem

    Saat menerima barang (orderpoint)

    123

    2914:39:31

    Betulkan ika IRA < 95

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    Betulkan ika IRA < 95

    Controlsample

    Lakukan secara berkala Temukan penyebab masalah,betulkan

    perbedaannya &Tetapkan programuntukperbaikan dan peningkatan IRA

    Dilakukan oleh personel yangberpengalaman Tidak berarti menghilangkan physicalinventories

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    Accuracymaintenance

    A=12 Perencanaan/

    = C=2

    pen a wa an yc eCount

    Conto CounterWor s eet

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    126 3214:39:31

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    Jikasesuaiden ansistemterimahasilperhitungan

    a a sesua a errorpo cyJika tidak sesuai lihat transaksi

    dengankemungkinansalahdancari

    127 3514:39:31

    a sys emcoun ac ua coun

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    a sys em coun ac ua coun ,

    periksalah: engeuaran tap e um a a transa s

    Shipments tanpa transaksi

    Backflush pending

    Under issues in the s stem to WIP

    shipping, etc.)

    128 3614:39:31

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    J ika system count < actual count,per sa a :

    Receipts tanpa transaksi

    Over issues dalam systemScrap tidak dilaporkan

    129 3714:39:31

    RekonsiliasihasilCount

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    Periksa juga:Kesalahan counting

    dengan O (o)

    Item terdapat pada lokasi lain

    130 3814:39:31

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    13181

    3914:39:31

    semuapartyangmasuk(artinyastockbertambah)akanmasukkolomminus

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    minus

    semuapartyangkeluarakanmasukkolomplus

    tambahkanactualqty(hasilcyclecounting)denganqtydikolompluslalukurangidengansemuadikolomminus

    inilahnetqty

    bandingkannetqtydenganyangadadisystem

    bilamasihterjadiperbedaanartinyaitulahselisihakhiryangbisadi

    writeoffataudicarilagipenyebabnya

    13214:39:31

    LatihanRekonsiliasins ru s

    Anda diminta melakukan rekonsiliasi setelah cyclecountBacalah tiap baris dengan baik dan isilah pada kolom yangcocok " "

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    Partnumber12345dan isilah kolom berikut:

    Computeronhandquantity(qtysystem)=498 Actualpartsditemukan di storeroom=675 Initialerror=177pieces

    25piecessudah dikirim ke productionuntuk digunakan assemblytapi materialyangdiambil belum di entryke sistem 15piecestelah dikirim customershippingpapermenunggu entry 225partsyangtelah diterima dari vendorsudah masuk dalamstoreroombelum dibuat transaksi

    Workorder12345utk 10piecestelah lengkap dan telah dipindahkanke lokasi untuk workorderyangtelah siap tapi belum ada transaksi

    133 4114:39:31

    FormatRekonsiliasi

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    Total

    Actual Part counted dalam inventory

    Tambahkan semua lus

    Kurangi semua minus

    Net

    134

    System Count

    Kurangi Net dari aktual = Aktual error

    14:39:31

    FormatRekonsiliasi

    Part yang dibeli diterima di gudang menunggu transaksiPart yang dibeli dimasukkan dalamstock menunggu putaway

    Material di indahkan ke work order menun u transaksi keluar

    Material dipindahkan ke work order menunggu backflush

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    Material dipindahkan ke work order menunggu backflush

    Part untuk work order diterima di stock menunggu transaksi

    Part untuk work order di transfer ke stock menunggu putaway

    Part dipindahkan dari stock ke produksi tanpa transaksi

    Item dikirimkan (shipping)menunggu shipping document

    Item yang dijual di transaksikan sebagai shipped, masih dalamstock

    Total

    Actual Part counted dalam inventory

    Tambahkan semua lus

    Kurangi semua minus

    Net

    135

    System Count

    Kurangi Net dari aktual = Aktual error

    14:39:31

    JawabRekonsiliasiPlus Qty Minus Qty

    Part yang dibeli diterima di gudangmenunggutransaksi 225

    Part yang dibeli dimasukkan dalamstock menungguputaway

    Material dipindahkanke work order menunggutransaksi keluar 25

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    Material dipindahkan ke work order menunggubackflush

    Part untukwork order diterima di stock menunggutransaksi 10

    Part untukwork order di transfer ke stock menungguputaway

    Part dipindahkandari stock ke produksi tanpa transaksi

    Item dikirimkan (shipping)menunggu shipping document 15

    tem yang ua transa s an se aga s ppe , mas a am stoc

    Total 50 225

    c ua ar coun e aam nven ory

    Tambahkan semua plus + 50

    Kurangi semua minus -225

    136

    System Count 498

    Kurangi Net dari aktual = Aktual error 214:39:31

    LaporanBerdasarkanPenyebab

    Dapatdigunakan

    untuk

    dasar

    perbaikan

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    13714:39:31

    Shortcuts/jalanpintas

    Beberapa jalan pintas untuk mengurangi

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    Waktu menghitung Saat Qtydi sistem negatif ()

    Saat Qtydi sistem =0

    Saat orderditerima

    Multiplelocations.Hitunglah hanya pada

    lokasi yangaktif

    Reasonableness:lihat labelyangtertulis atau estimasi

    138

    jumlahnya untuk itemyangberada pada lokasi slow

    moving4614:39:31

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    CycleCounting PhysicalInventory Investigasi penyebab &

    membetulkannya

    Tidak melakukan analisapenyebab

    terusmenerus

    Memerlukan personel

    analysis

    Memerlukan biaya besaryangterlatih tapi dampaknya sebentar

    Semua orang terlibat

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    Perhatian pada detail Memahami physicalstock(eg:

    identifikasi produk,satuan dsb)

    Ingin sempurna

    14:39:31 140

    Kualifikasi Investigator

    Perhatian pada detail ,

    Sherlock Holmes mentality

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    SherlockHolmes mentality

    Memahami sistem komputer logs(urutan historiskeluar masuk data)

    Kemampuan Interpersonalskill

    Memahami perpetualinventorysystemdesign

    membuat laporan

    14:39:31 141

    SafetyStock

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    14:39 142

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    disiapkan untuk proteksi terhadap

    u uas e u u an eman dan/atau supply(leadtime).

    14:39 143

    Reorder

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    point

    a b c

    LT

    ,B: stock out terjadi pas saat barang datang dari vendor

    C: tidak terjadi stock out

    7214:39 144

    SafetyStocktergantung

    pada

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    Variasi kebutuhan selama leadtime Servicelevel

    Leadtime.Makin an an leadtime makin

    besar safetystockyangdibutuhkan

    7314:39 145

    Kebutuhan bervariasi dengan

    QQ

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    ve

    l

    entory

    le

    Reorderpoint,R

    In

    LTLTTime

    LTLT

    00

    7414:39 146

    ReorderPointdengan

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    ve

    l

    ve

    l

    ReorderReorder

    QQ

    entory

    l

    entory

    l

    point,point,RRIn

    I

    n

    00

    SafetyStock

    TimeTime7514:39 147

    ReorderPointforaServ ceLeve Pro a ty

    Probabilityofmeeting demand during

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    meetingdemandduringleadtime=servicelevel

    Probabilityof

    a

    stockout

    zd L

    RRDemandDemand

    7714:39 148

    Untuk menghitung safety stock perlu

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    Untukmenghitungsafetystockperlu

    pemakaian

    Standarddeviationadalahselisihforecastvsactualkemudiandi

    kwadratkandandicariakarnya

    14:39 149

    Contoh

    Mingu Actual Pemakaian Forecast Deviasi

    dua

    1 4900 5000 -100 10000

    2 5000 5000 0 0

    3 5100 5000 100 10000

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    3 5100 5000 100 10000

    4 5400 5000 400 160000

    5 5300 5000 300 90000

    6 4800 5000 -200 40000

    7 5200 5000 200 40000

    8 5000 5000 0 0

    -

    10 5200 5000 200 40000

    Total 50,800 50000 1600 400000

    Std deviation = (400,000/no. of period-1) =

    = (400,000/ (10-1) = 211

    8014:39 150

    nn--

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    N digunakan bila ada lebih dari 30 periode N-1 digunakan bila N lebih kecil dari 30 periode

    Dari contoh sebelumnya : std deviation(400,000/(10-1))

    = 211

    8114:39 151

    Safetystock=safetyfactorxstandard

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    y y

    Safetyfactorditentukan oleh servicelevel

    on o a a ng n serv ce

    eve

    ma asafetyfactornya adalah 0.84

    Kemudian 0.84dikalikan dengan standard

    deviationuntuk mendapatkan safetystock

    14:39 152

    ContohServiceLevel

    Berapa servicelevelutk suatu itemdimana

    kebutuhan tahunannya 25,000units&order

    tit 5 000 it ? M t h

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    quantity5,000units?Managementhanya

    mem er o erans a s oc ou per a un.

    N=25,000/5,000=5

    S.L.=5 1x100%=80%

    Bagaimana jika

    orderQuantitynya

    menjadi 1,000?

    15314:39 153

    Table of service level

    Desiredservice level Safety Facto

    50 0

    80 0 84

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    80 0.84

    .

    90 1.28

    95 1.65

    97.72 2

    98 2.05

    99 2.33

    99.87 3

    99.93 3.2.

    8214:39 154

    Desired servicelevel

    Safety stock = safety factor X std deviation

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    50% 0 0 211x

    95% 349 1.65 211

    99% 492 2.33 211

    8414:39 155

    contoh: management policy, 1 stock out per tahun

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    kebutuhan/thn: 52,000 & order qty: 2,600. Std deviasi 100, lead time 1minggu

    Hitunglah:

    1. jumlah order / thn

    2. service level

    3. safety stock

    4. reorder point

    1. j

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    1. jumlah order/thn =52,000/2,600=20x/thn

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    = . 1)/20=95%

    =. , . .

    stock=1.65x100(stddeviasi)=165unit

    = = =. , , .

    x1000=1000.ROP=DDLT+SS=1000+165=1165

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    leadtimemeningkat,safetystockakan meningkat

    meningkat tidak proporsional

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    dilakukan ad ustment bila lead time menin kat

    Newsafetystock=oldsafetystockx (newinterval/oldinterval)

    contoh:safetystock150&leadtime2minggu.Bila leadtimejadi 3minggu berapaSSnya?

    NewSS=150x =150x1.22=183unit

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    managementmemberikan toleransi 1xstockout/thn

    Kebutuhan/thn 100,000&orderqty10,000

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    Leadtime2minggu,datahistoris 10mingguterlampir

    2. Servicelevelnya

    3. Safetystockuntuk serviceleveltsb

    4. Reorder ointn a

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    Latihan 1

    Hitun lah Standar Deviasi

    Actual DeviasiMinggu Pemakaian Forecast Deviation pangkat dua

    1 2100 2000

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    1 2100 2000

    3 2600 2000

    4 1400 2000

    5 1800 2000

    6 2300 2000

    7 2200 2000

    8 1600 2000

    10 2200 200014:39 160

    Latihan 1

    Hitun lah Standar Deviasi

    Actual DeviasiMinggu Pemakaian Forecast Deviation pangkat dua

    1 2500 2000

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    3 2800 2000

    4 1300 2000

    5 1800 2000

    6 2200 2000

    7 2100 2000

    8 1600 2000

    10 1200 200014:39 161

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    Imanadi085225019360

    [email protected]

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