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Matt Mecham
03-08-1996, 10:00 AM
Dear All:

Following is a summary of the responses that I received regarding my
request for information about the HIC and other ways of predicting head
injury using accelerometer data. I would like to thank the individuals
who responded to my request. If anyone has any further comments or
information I would welcome your input.

Thank You
Matthew D. Mecham
matt.mecham@m.cc.utah.edu

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>From MKLEINBERGER@nhtsa.dot.govMon Mar 4 18:43:02 1996
Date: Fri, 05 Jan 1996 14:51:59 -0500
From: Mike Kleinberger
To: matt.mecham@m.cc.utah.edu
Subject: HEAD INJURY CRITERION (HIC) -Reply

Matt -

I think that I can be of some help to you. Here at the National Highway Traffic
Safety Administration, we are very interested (and very involved) in predicting
head injuries from acceleration data. First of all, if you need a program to
calculate HIC, you can get it from our Web site. The URL for our ftp site is
ftp://ftp.nhtsa.dot.gov/pub/nrd/nrd10/software/tools/. There are some DOC files
available on the HIC program, and also binaries for a variety of platforms.

Regarding novel approaches to predicting head injuries, I would recommend that
you check out a paper that was just published at the 39th Stapp Car Crash
Conference (November 1995). The reference is as follows:

DiMasi FP, Eppinger RH, and Bandak FA. Computational analysis of head
impact response under car crash loadings. SAE Paper No. 952718, 39th Stapp
Car Crash Conference, November 1995.

This paper describes our current thoughts on using a finite element model of the
head in conjunction with accelometer data to predict strain in the brain tissue,
and thus brain injury.

I hope that this information is helpful.

Good Luck,
Mike Kleinberger

*****************************************

Dr. Michael Kleinberger
National Highway Traffic Safety Administration
Biomechanics Research Division

E-mail: mkleinberger@nhtsa.dot.gov

*****************************************


>>> matt mecham 01/05/96 01:28pm >>>
Dear Netters:

I am in search of a program that will calculate a HIC value (Head Injury
Criterion) for complex acceleration-time profiles. I am aware of the basics of
the HIC calculation for simple profiles, but understand that different methods
must be used for multiple peak acceleration data. If anyone has written such a
program, has access to a public domain program or specific information on how
this might be done, please contact me.

In addition, if anyone is aware of any novel approaches utilizing
acceleration-time profiles to predict head injury and set tolerance levels I would
appreciate the information. If significant interest is shown I will post a summary
of the replies.

Thanks in advance.

Matthew D. Mecham


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>From A.McIntosh@unsw.edu.auMon Mar 4 18:49:23 1996
Date: Tue, 9 Jan 1996 14:57:50 +1100
From: Andrew McIntosh
To: matt mecham
Subject: Re: HEAD INJURY CRITERION (HIC)

Dear Matt,
there are a number of algorythms for HIC, mostly the time period
over which HIC is calculated is defined. It would be best to consult an SAE
recommendation or FMVSS for a suitable definition. Otherwise general
information about HIC can be found in numerous papers presented over the
years at the Stapp and IRCOBI conferences. You will find many conflicting
opinions about HIC. To understand and evaluate HIC you must look at how the
Wayne State Uni. Tolerance Curve was derived.

There are more direct applications of the head's resultant acceleration time
history, e.g. maximum- or 3 ms. acceleration values. I presented a paper at
the 1993 Stapp conference where we used the logistic regression model to
develop relationships between injury predictors, e.g. maximum head
acceleration and HIC, and AIS head injury severity. This method permits one
to propose an injury tolerance threshold. The sample size is limited, as in
almost all areas of impact biomechanics, therefore the confidence limits are
wide.

Other applications of the head's acceleration are to use it as an input into
a numerical model, e.g. Stalnaker's (R.L) Translational Energy Criteria or
the Mean Strain Criterion. Head acceleration could also be used as an input
into a good FE model of the head, which then provided an output appropriate
for the establishment of injury. There is presently a great deal of
research in this area.

If you have any specific questions please write to me directly.

Best wishes,

Andrew Mc. ******************************************** ANDREW McINTOSH
(PhD) Department of Safety Science The University of New South Wales
Sydney Australia 2052 ph:*61 *2 *3855413 fax: *61 *2 *3856190 EMail:
a.mcintosh@unsw.edu.au


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>From pbishop@healthy.uwaterloo.caMon Mar 4 18:50:34 1996
Date: Mon, 15 Jan 1996 15:47:44 -0500 (EST)
From: pbishop@healthy.uwaterloo.ca
To: matt.mecham@m.cc.utah.edu
Subject: Calculating HIC


Dear Matt
At the University of Waterloo we have been calculating the HIC for a
number of years.This has been in conjunction with our work on head
protection in hockey and football.


The program was written several years ago by John Pezzack in Quick Basic
and it runs on a PC. The calculation takes a long time (compared to
calculating the GSI) because of the need to maximize HIC.

Just out of curiosity, why are you calculating HIC anyway? You probably
know already that HIC values in helmet testing are about 18% lower than
GSI values and both are merely boundry estimates of head injury
occurrance,although GSI has proven to be useful in setting helmet standards.
Since neither index obeys a scaling law their usefullness is limited.

In any event if you want more info re a computer program you can contact
me via email or by calling me at 519 885-1211 ext 2269.

Good luck with your search and project.

Pat Bishop PhD Professor

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>From 75144.3653@compuserve.comTue Mar 5 10:00:03 1996
Date: 05 Mar 96 10:06:17 EST
From: Fred
To: "Matthew D. Mecham"
Subject: HIC

Hello,

Just wondering what responses you got to your 1/5/1996 HIC query.

Do you have anything you could send me?

here is somthing:
C PROGRAM **HICOP** - OPTIMIZED HIC ALGORITHM FROM DOT 9/25/85
DIMENSION R(0:8000),JL(10000),KL(10000)
COMMON X(8000,25),T(8000)
DOUBLE PRECISION RC,RM,SC,SM
CHARACTER*60 NAME,LABEL
DATA NAR/10000/
NAME='**PROGRAM HICOP**'
CALL INOUT(NAME,1,0)
c WRITE(6,1)
c 1 FORMAT(10X,'**PROGRAM HICOP**')
READ(10,2)NPT,IFILE,NCHN,LABEL
2 FORMAT(3I4,A60)
write(6,17)npt,ifile,nchn,label
17 format(3i4,1x,a60)
if(npt.gt.8000)then
write(6,30)
30 format('npt too large, must be less than 8000')
close(10)
stop
end if
if(nchn.gt.24)then
write(6,31)
31 format('nchn too large, must be less than 25')
close(10)
stop
end if
DO 3 I=1,NPT
3 READ(10,4)T(I),(X(I,J),J=1,NCHN)
4 FORMAT(F8.2,24F10.3)
close(10)
DEL=(T(2)-T(1))/1000.
C FORM RESULTANT ARRAY
DO 6 I=1,NPT
6 X(I,25)=0.0
16 WRITE(6,5)
5 FORMAT('INPUT CHANNELS TO BE USED FOR RESULTANT'/'XX XX XX')
READ(5,7)I1,I2,I3
7 FORMAT(3(I2,1X))
IF((I1.EQ.0).AND.(I2.EQ.0).AND.(I3.EQ.0))THEN
CALL STOP
stop
END IF
IF(I1.EQ.0)I1=25
IF(I2.EQ.0)I2=25
IF(I3.EQ.0)I3=25
DO 8 I=1,NPT
8 R(I)=SQRT(X(I,I1)**2+X(I,I2)**2+X(I,I3)**2)
R(0)=0.0
C COMPUTE SUM (INTEGRAL) ARRAY USING TRAPEZOID RULE
SM=0.D0
RM=ABS(R(0))
R(0)=0.0
DO 9 I=1,NPT
RC=ABS(R(I))
SC=SM+.5*(RC+RM)
R(I)=SC
SM=SC
9 RM=RC
C INITIALIZE VARIABLES
FMAX=0.0
JMAX=0
KMAX=0
JL(1)=0
KL(1)=-1
NWU=NPT
IBR=1
IER=1
INC=-1
IBL=NAR
C BEGIN A ROUND OF REGION EVALUATIONS
10 IL=IBL-INC
IEWR=0
DO 11 IR=IBR,IER,INC
JLI=JL(IR)
IF(JLI.GT.0)THEN
NJ=NWU
ELSE
JLI=ABS(JLI)
NJ=MAX0(NWU-1,0)
END IF
KLI=KL(IR)
IF(KLI.GT.0)THEN
NK=NWU
ELSE
KLI=ABS(KLI)
NK=MAX0(NWU-1,0)
END IF
KUI=KLI+NK
C BLANK LINE
IF((NJ.EQ.0).AND.(NK.EQ.0))THEN
C THIS IS A SINGLE POINT REGION - EVALUATE
F=(R(KUI)-R(JLI))*(KUI-JLI)**(-.6)
IF(F.GT.FMAX)THEN
FMAX=F
JMAX=JLI
KMAX=KUI
END IF
ELSE
C THIS IS A FINITE REGION WITH FEASIBLE POINTS - BOUND
JUI=JLI+NJ
FS=R(KUI)-R(JLI)
IF(FS*MAX0(KLI-JUI,1)**(-.6).GT.FMAX)THEN
C REGION IS POSSIBLY OPTIMAL - EVALUATE AND PARTITION
F=FS*(KUI-JLI)**(-.6)
IF(F.GT.FMAX)THEN
FMAX=F
JMAX=JLI
KMAX=KUI
END IF
IF((IL+4*INC)*INC.GT.IR*INC)THEN
C SIZE LIMITS REQUIRE EXHAUSTIVE ASSESSMENT TO FINISH
IF(IEWR.EQ.0)WRITE(6,12)
12 FORMAT(' **HICOP ARRAY SIZE EXCEEDED - EXHAUSTIVE EVAL. NEC.')
IEWR=1
DO 13 KJD=KUI-JLI,MAX0(KLI-JUI,1),-1
SKJM=0.0
DO 14 J=MAX0(JLI,KLI-KJD),MIN0(JUI,KUI-KJD)
SKJ=R(J+KJD)-R(J)
IF(SKJ.GT.SKJM)THEN
SKJM=SKJ
JM=J
END IF
14 CONTINUE
FB=SKJM*KJD**(-.6)
IF(FB.GT.FMAX)THEN
FMAX=FB
JMAX=JM
KMAX=JM+KJD
END IF
13 CONTINUE
ELSE
CALL PART(JLI,JUI,NJ,NWU-NJ,KLI,KUI,NK,NWU-NK,IL,INC,JL,KL)
END IF
END IF
END IF
11 CONTINUE
IF(ABS(IBL-IL-INC).GT.0)THEN
C SOME REGIONS REMAIN - SET UP BOUNDARY INDEX ARRAYS
ITMP=IBL
IBL=IER
IER=ITMP
IBR=IL
INC=-INC
NWU=NWU/2
GO TO 10
ELSE
C DONE - NO REGIONS REMAIN - REPORT RESULTS
HIC=DEL*FMAX**2.5
T1=1000*JMAX*DEL
T2=1000*KMAX*DEL
WRITE(6,15)HIC,T1,T2
15 FORMAT(' HIC= ',F15.2,' T1= ',F10.2,' T2= ',F10.2)
GO TO 16
END IF
CALL STOP
stop
END
SUBROUTINE PART(JLI,JUI,NJ,NJD,KLI,KUI,NK,NKD,IL,INC,JL,KL)
C PERFORMS PARTITIONING OF POSSIBLY OPTIMAL REGIONS
DIMENSION JL(*),KL(*)
J2M=2*MOD(NJ,2)
NJ2=NJD*J2M
JMU=(JUI-NJ/2)*(1-NJ2)
K2M=2*MOD(NK,2)
NK2=NKD*K2M
KMU=(KUI-NK/2)*(1-NK2)
C FIRST REGION
IL=IL+INC
JL(IL)=JMU
KL(IL)=KMU
C SECOND REGION IF FINITE WIDTH ALONG J AXIS
IF(NJ.NE.0)THEN
JLI=JLI*(J2M-NJ2-1)
IL=IL+INC
JL(IL)=JLI
KL(IL)=KMU
END IF
IF(NK.NE.0)THEN
KLI=KLI*(K2M-NK2-1)
C THIRD REGION IF FINITE WIDTH ALONG J AND K AXES
IF(NJ.NE.0)THEN
IL=IL+INC
JL(IL)=JLI
KL(IL)=KLI
END IF
C FOURTH REGION IF FEASIBLE AND FINITE WIDTH ALONG K AXIS
IF(ABS(KMU)-1.GT.ABS(JMU))THEN
IL=IL+INC
JL(IL)=JMU
KL(IL)=KLI
END IF
END IF
RETURN
END



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