sci.op-research

On 4=E6=9C=888=E6=97=A5, =E4=B8=8B=E5=8D=884=E6=97=B621=E5=88=86, Wit Jakucz=
un wrote:
> Dnia Tue, 8 Apr 2008 00:58:29 -0700 (PDT)
> minben napisa=C5=82(a):
>
>
>
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>
> > On 4=E6=9C=888=E6=97=A5, =E4=B8=8B=E5=8D=883=E6=97=B647=E5=88=86, Wit Ja=
kuczun wrote:
> > > Dnia Tue, 8 Apr 2008 00:33:23 -0700 (PDT)
> > > minben napisa=C5=82(a):
>
> > > > My idea is to define a binary variable Yi,d to describe if a good i
> > > > arrives before day d (it can be get from Di and d),and for d=3D1 to
> > > > 31,we calculate everyday's storage by adding Yi,d*Wi for all i and
> > > > d ,then plus L and minus d*c. At last we let it not larger than T.
>
> > > > But it's so complex and I believe there is some simpler way,but I
> > > > can't find it. Can anyone help me?
>
> > > What is complex for you in your idea?
>
> > For one item Yi,d*Wi =C2=A0it may be calculated for many times (for
> > different d),so I think there may be a better way.
>
> Have you conducted any experiments? Do it first then think
> about improving your formulation.
>
> Best regards
> --
> [ Wit Jakuczun =C2=A0 =C2=A0 ]
> [ WLOG Solutions =C2=A0http://www.wlogsolutions.com]- =E9=9A=90=E8=97=8F=
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>
> - =E6=98=BE=E7=A4=BA=E5=BC=95=E7=94=A8=E7=9A=84=E6=96=87=E5=AD=97 -

The problem I mentioned is part of my project. I have implemented it
in cplex. I found this part increased many nonzeros. So I want to
improve it.