Aqm Case Study

8/20/2019 Aqm Case Study

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Introduction As the global economic condition changing in a rapid motion, generally in an industry morefocus is given on profit margin, customer demand for high quality product and improvedproductivity. In garment manufacturing, it is usual to see a lot of rejected garments aftershipment. These non-repairable defects may occur due to low quality raw materials or faultyprocess or employee casual behavior. In the contemporary world of manufacturing, due to highcompetitive nature of the market, different companies have started to look for differentapproaches and practices to reduce the defect percentage. areto Analysis helps to identifydifferent defects and classify them according to their significance. These defects often lead tothe rejection of raw materials. To determine possible root causes of rejection, !ause-"ffect#iagram is also a very useful tool. It helps to identify, sort, and display causes of a specificproblem or quality characteristic. It graphically illustrates the relationship between a givenoutcome and all the factors that influence the outcome and hence to identify the possible rootcauses.

CASE STUDY:

Background Of The Study : At present the success of the $eadymade %arments sector highly depends on several factorssuch as manufacturing lead time, quality of product, production cost etc. These factors arehampered due to various defects in the products. These defects can be repairable that leads torework or non-repairable that leads to rejection. $ework in the garments industry is a commonwork that hampers the smooth production rate and focus poor quality products having animpact on overall factory economy. &inimi'ation of reworks is a must in quality and productivityimprovement. $ework is a vital issue for poor quality product and low production rate. (yreacting quicker in minimi'ation of reworks to make a product as per customer demand withe)pected quality, the company can invest less money and more costs savings. *hereasrejection causes waste and deceases resource efficiency.

In this conte)t $eadymade %arments sector is selected for research work. The selectedgarment factory consists of several departments such as cutting, sewing, finishing, packing etc. Among these departments the sewing section is selected.

Objective :This study tried to e)tract the common scenario of $eadymade %arments sector of(angladesh by depicting the e)isting condition of sewing section.

About The Company:

!ompany +ame $ainbow Apparel imited

ocation alishahar college road, !hittagong"stablished //0

roduct type *oven shirt, *oven pant

+umber of production line 1

Total worker 1/

roduction capacity per day 2/// !3

*orking hour per day 4/ ours 5ma)imum6

(uyers ong 3treet 573A6, Target 573A6

Findings :(y observation and data collected from the management level, different types of defects in theproduction lines were observed. These defects cause reworks and rejection which leads totime waste and decrease in productivity. (y concentrating on those few repetitive defects inparticular positions, most of the defects can be minimi'ed. 3o with this respect, identification of


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those particular defects and positions using areto Analysis, followed by the analysis of thedefects using cause-effect diagram was carried out.

Overview of Production Line

Existing layout of a single production line

Data Coection8our months defect data was collected from management months starting from 9ctober /4to :anuary /42. The data has been taken from five production lines of sewing section duringthe production of woven pant. In the case of woven pant production 1/ defect positions areidentified where 1 types of defects occur. Among the defect types 7ncut Thread for allpositions are counted together for 1/ positions. 3imilarly two other defect types, 3pot and 9il

&ark are also counted together. +umber of defects of all the production lines are listed on the!heck 3heet by ;! supervisors if found any.

SL No. DEFECT TYPE DEFECT CODES

1 Skipped Stitch A2 Broken Stitch B

3 Loose Tension C

4 ne!en Stitch "# $un %ff Stitch E& Slanted '( )igh*Lo+ ,

- .uckering )/ Crooked 01 %ut of Shape

"efect types +ith their corresponding codes


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Four month com!ined defect d"t" for woven #"nt

areto Analysis


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areto Analysis was performed based on four months combined defect data of 1 productionlines from the sewing section for woven pants. 8rom this analysis the areas wherema)imum defects occur can be identified.

ere hori'ontal a)is represents defect positions, vertical a)is at left side represents defectamount and vertical a)is at right side represents defect percentage. The defect positions withtheir respective defect amounts have been represented by the blue colored bars. Thecumulative percentage and ?/@ line are represented respectively by red and green color. After the analysis top defect position bars are replaced with yellow color.

Observations from !areto Anaysis for Top Defect !ositions

7ncut Thread is the most frequent defect with as much as 2.@ of the total.

3pot is the second most frequent defect with /./@ of the total.

Among other defects contribution of *aist (elt is 44.0@, (ottom em is 4/./B@, 3ide

3eam is 0.2/@ and *aist (elt Top 3titch is 0.4B@. These si) top defect positions are the where ?.10@ of total defects occur.

8urther areto Analysis need to be performed on the top defect positions to identify the

vital few defect types that are responsible for ma)imum amount of defect.


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Further !areto Anaysis for Top Defect Types As 7ncut Thread and 3pot are individually defect types as well as defect positions, there is noneed of further analysis for identifying top defect types in those two positions. ence furtherareto Analysis was performed for *aist (elt, (ottom em, 3ide 3eam and *aist (elt Top3titch.

P"reto An"$%i for &"it 'e$t:

Defect T%#e Defect Code Defect Amount

isile Top Stitch 5 /-(

Broken Stitch B /(&

$a+ Edge 6 (

ne!en Stitch " #3-

Skipped Stitch A 231

Crooked 0 1&1

$un %ff Stitch E 1#4

.uckering ) 134

T+isting 123

%ut of Shape --

%!erlap % (2

Loose Tension C 4&Lael 7istake 42

0nco7plete . 4

.ullness 8 3

isile oint 9 14

)igh*Lo+ , (

.osition L #

5rong S.0 $ #

Slanted ' 4

T%TAL 4422

Observations from the Anaysis:

=isible Top 3titch 5*6 is the most frequent defect type with .2@ of total *aist (elt

defect. Among other defect types contribution of (roken 3titch 5(6 is ./@, $aw "dge 5C6 is

4.2/@, 7neven 3titch 5#6 is 4.4@ and 3kipped 3titch 5A6 is 1.@. 3o these five defect types are responsible for D./?@ of total *aist (elt defects.

P"reto An"$%i for 'ottom (em

!erc

enta

ge

Def

ect

Am

oun

t


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7neven 3titch 5#6 is the most frequent defect type with .B4@ of total (ottom em

defect. Among other defect types contribution of (roken 3titch 5(6 is 1.0@ and 3kipped 3titch

5A6 is B.0@. 3o these three defect types are responsible for .D@ of total (ottom em defects.

P"reto An"$%i for Side Se"m:

Def ect

Am

oun

t

!ercenta

ge


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3kipped 3titch 5A6 is the most frequent defect type with 2.?@ of total 3ide 3eam

defect. Among other defect types contribution of $aw "dge 5C6 is B.D?@, (roken 3titch 5(6 is

.14@ 3o these three defect types are responsible for ?/.2/@ of total 3ide 3eam defects.

P"reto An"$%i for &"it 'e$t To# Stitch:

!erc

enta

ge

Def

ect

Am

oun

t


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Defect T%#e

Defect Code

Defect Amount

Broken Stitch

B

(/-


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isile Top Stitch

5

4/

Skipped Stitch

A

313

ne!en Stitch


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"

24#

.uckering

)

/&

$un %ff Stitch

E

((


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$a+ Edge

6

%!erlap

%

&1


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Loose Tension

C

3&

%ut of shape

3&


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.ullness

8

2&

Crooked

0

22

.osition

L

13


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T+isting

12

0nco7plete

.

11


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isile oint

9

11

Slanted

'

(


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)igh*Lo+

,

#

5rong S.0

$

2

Lael 8istake


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1

T%TAL

232(


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(roken 3titch 5(6 is the most frequent defect type with 2B.D@ of total *aist (elt Top

3titch defect. Among other defect types contribution of =isible Top 3titch 5*6 is 4./0@, 3kipped

3titch 5A6 is 42.B1@ and 7neven 3titch 5#6 is 4/.12@.

3o these four defect types are responsible for D.22@ of total *aist (elt Top 3titch defects.

)"*or Concernin+ Pro!$em

Def

ect

Am

ount

!er

cen

tage


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"esut of the !areto Anaysis After areto Analysis it is found that total seven types of defect in the identified top defectpositions are responsible for ma)imum amount of defects. The defect types and thecorresponding positions with their respective defect amount are shown in table.


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)A,O- CONCE-NIN A-EAS

Defect "mount

Defect T%#e

Defect Poition


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ncut Thread :;<

At # positions

-/--

Spot :S<

At # positions

(-4#

5aist Belt

231

Skipped Stitch :A<

Botto7 )e7

/42


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5aist Belt Top Stitch

313

Side Sea7

(-3

5aist Belt

/(&


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Broken Stitch :B<

Botto7 )e7

/-


(/-


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Side Sea7

#3(

5aist Belt

#3-

ne!en Stitch :"<

Botto7 )e7

143


24#


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$a+ edge :6<

5aist Belt

(

isile Top Stitch :5<

5aist Belt

-/(

T%TAL A8%;T

2(#(


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Total number of defects E #$%&$

Total number of defects in major concerning area E '$()$

ercentage of defects in major concerning area E F @ G $*+,(-

There are 1 defects types of which 7ncut Thread, 3pot and 9il &ark are individually countedtogether for 1/ positions. $est of the defect types can occur in 1/ different positions of the

woven pants.

3o the number of total concerning area is H1/ J 1/ 57ncut Thread6 J 1/ 53pot6 J 1/ 59il

&ark6K E *')(

which is responsible for total amount of defects

(ut we have identified total 441 concerning areas by areto Analysis which is responsible for4.B/@ defects.

Total number of concerning area E *')(

Total number of major concerning area E **)

ercentage of major concerning area E F @ G &+'(-

3o by concentrating only on D./@ areas most of the defects can be reduced.


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(ier"rch% of C"ue "nd C"ue/Effect Di"+r"m

8rom areto Analysis top defect positions are identified and by further analy'ing identificationof top seven defect types in those positions can even be done. Those defect types are asfollowsL-

0. UNCUT T(-EAD

(ier"rch% of C"ue


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S.+ /O+

CA0S1S

F"1201/C3 4O0T OF '(5

*

9perator inefficiency

'(


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'

Improper trimming

*6

#

Improper finishing

**

C"ue/Effect Di"+r"m


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Su++eted So$ution

Cause Types

Causes


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Suggested Soutions

&an


rovide adequate training to the operators.

Improper trimming

rovide thread cutter to every operator and make used to.


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To cut thread properly, start regularly checking system to check


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&achine

Improper finishing

the auto trimming machine is properly functioning or not.

Improve quality inspection system.


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SPOT

(ier"rch% of C"ue

S.+ /O+

CA0S1S

F"1201/C3 4O0T OF '(5

*

9perator carelessness

'(

'

&ishandling

*$

#

#efective machine

*#


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,

#irty work area

(6

C"ue/Effect Di"+r"m


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Suggested Soutions

Cause Types

Causes


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Suggested Soutions

&ishandling

*ash hands of operator before starting work and after lunch,

&an

establish preventive maintenance.


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9perator carelessness

Improve supervision.

&achine

#efective machine

!lean machine properly twice in a day.

&ethod

#irty work area

Ceep workplace neat and clean.


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1. 2ISI'LE TOP STITC(

(ier"rch% of C"ue

S.+ /O+

CA0S1S

F"1201/C3 4O0T OF '(5

*


'(

'

Improper trimming

*)

C"ue/Effect Di"+r"m


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Suggested Soutions

Cause Types

Causes


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Suggested Soutions

&an


rovide adequate training to the operators.

Improper trimming

Teach operators.

3. '-O4EN STITC(

(ier"rch% of C"ue

S.+ /O+

CA0S1S


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F"1201/C3 4O0T

OF '(5

*

Inappropriate thread tension

*$

'

*rong needle si'e and thread si'e

*)

#

+eedle plate, pressure foot, needle holes may have sharp edges

*'

,

")cessive abrasion or chemical degradation of the thread

($


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during washing

)

*eak thread

(6

C"ue/Effect Di"+r"m


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Suggested Soution


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Cause Types

Causes

Suggested Soutions

Inappropriate thread tension


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Tension of the thread properly adjusted.

&achine

+eedle plate, pressure foot, needle

Inspect the needle point at regular intervals and check

for sharp or burred points.


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holes may have sharp edges

3harp edges should be removed.


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*rong needle si'e and thread si'e

+eedle si'e and thread si'e should be synchroni'ed.


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&ethod

")cessive

abrasion

or chemical

degradation

of the

thread

during

3pecial care should be taken during washing.


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washing


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&aterial

*eak thread

3elect good quality thread which is free from flaws.

5. -A& EDE

(ier"rch% of C"ue

S.+ /O+

CA0S1S

F"1201/C3 4O0T OF '(5


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*

Improper folding

'(

'

Improper seaming

'(

C"ue/Effect Di"+r"m


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Su++eted So$ution

Cause Types

Causes

Suggested Soutions


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&an

Improper seaming

Teach operator

&ethod

Improper folding

Improve or change folding system


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6. UNE2EN STITC(

(ier"rch% of C"ue

S.+ /O+

CA0S1S

F"1201/C3 4O0T


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OF '(5

*

9perator speeding up machine too rapidly

*$

'

9perator holding back or pulling fabric through in variance with

*#


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correct machine feed

C"ue/Effect Di"+r"m

Su++eted So$ution

C"ue T%#e

C"ue t%#e


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Su++eted o$ution

%perator

speeding

up 7achine

Control the speed of 7achine= use right needle and correct

too rapidly

feed control>

8an

%perator

holding

ack


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or

07pro!e the skill of operator= use good ?uality se+ing

thread= and pro!ide standard ?uality specification>

pulling

faric

through

in


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!ariance

+ith correct 7achine

;e!er pull on the faric +hile se+ing= let it e taken up

feed


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y the 7achine>


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6+ S4IPPED STITC(

(ier"rch% of C"ue

SL. NO.

CAUSES

F-E7UENCY 8OUT OF


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19:

0

;eedle deflection or ending

0;

1

Loop si@e or needle is s7all

03

3


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Tension !ariation in lopper and needle thread

00

5

)ook= lopper or needle is not ale to hold the thread loop in proper

00

ti7e

6

07proper handling of cut pieces


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9;

<

%perator inefficiency

91

C"ue/Effect Di"+r"m

Su++eted So$ution


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C"ue

C"ue

Su++eted So$ution

T%#e

8an


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%perator inefficiency

.ro!ide ade?uate training to the operators>

Ti7ing of hook or lopper +ith needle should e adusted

)ook= lopper or needle is not

properly>


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ale to hold the thread loop in

se needle +hich design to facilitate loop for7ation>


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proper ti7e


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$epair da7age 7achine parts>

8achine

Adust the needle height and testing efore ulk se+ing>


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;eedle deflection or ending

Check needle is properly 7ounted on the se+ing


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7achines +ith right eye position>

Adust tension properly>


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Select good ?uality thread +hich is free fro7 fla+s>

Tension !ariation in lopper and

needle thread


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Choice of se+ing thread in accordance +ith the needle

si@e>


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C"ue

C"ue

Su++eted So$ution

T%#e

Loop si@e or needle is s7all


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Adust needle and thread si@e>

8ethod

07proper handling of cut pieces

$educe gap et+een presser foot

and the hole of needle plate


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Suggested Additiona Features for 17isting !roduction .ines

There are four in-line ;! tables in each production line. These are currently placed insuch a way that when defects occur in first few work tables, it takes too much time toidentify the defects. (efore reaching the ;! table many operations are performed onthose defected pieces and it results in more reworks than necessary. That is why moreIn-line ;! tables should be included which will identify defects earlier, thus reducerework percentage.

After performing operation in each work table garments are kept mostly in the floor and

sometimes in paper bo)es which is one of the major reason for spot. To avoid thistrolley system should be introduced between every two workers and that will also resultin easy and smooth transportation

roviding a paper manual in every work table would be beneficial. It must contain

important issues for workers, such asL4. !lean table and machines before starting dayMs work.. *ash hands properly before starting work and after lunch.2. +ever pull on the fabric while sewing, let it be taken up by the machine.B. Adjust needle height, thread type and thread tension before bulk sewing.1. 7se right si'e of needle for specific type of fabrics.


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Pro#oed $"%out of " in+$e #roduction $ine


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"esut:

It was found that up to 4.B/@ defect can be reduced by concentrating only on D./@ areas.3uggestions related to those defect types are provided in the case study. It is almost


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impossible to achieve 'ero defects. (ut by taking effective measure it is possible to reach near 'ero defects.

Concusion

&inimi'ing defect is very important for ensuring the quality of products. The importance of thegarment industry in the economy of (angladesh is very high. The perceived quality of agarment is the result of a number of aspects, which together help achieve the desired level ofsatisfaction for the customer. owever, it should be kept in mind that 4@ defective product foran organi'ation is 4//@ defective for the customer who buys that defective product. 3omanufacturing the quality product is mandatory to sustain in this global competitive market.The first objective is to identify the top positions where ma)imum defects occur and second isto identify the top defect types in those positions. (y the help of areto Analysis top 0positions out of 1/ positions where ?.10@ of total defects occur were identified. Then furtherareto Analysis was done individually in those top positions to identify the top defect types.Thus indentifying about 441 major concerning areas which were responsible for 4.B/@ of thedefects in total. Then the hierarchy of causes for each defect types are organi'ed and the

causes of those defect types are shown individually using !ause-"ffect #iagram. 8inally somesuggestions were provided so as to apply them to minimi'e the frequency of those defects.Thus reworks could be effectively minimi'ed, thereby decreasing the rejection rate and wasteof time that will ultimately increase productivity.

Aqm Case Study

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