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                                                       EXHIBIT 10.15(d)

                                AMENDMENT NO. 2
                                      TO
                           ASSET PURCHASE AGREEMENT
                                BY AND BETWEEN
                        SPACE APPLICATIONS CORPORATION
                                      AND
                      APPLIED RESEARCH OF MARYLAND, INC.


     THIS AMENDMENT NO. 2, dated as of June  , 1997, by and between SPACE
APPLICATIONS CORPORATION and APPLIED RESEARCH OF MARYLAND, INC.

                                   RECITALS
                                   --------
     WHEREAS, the parties hereto executed and delivered the Asset Purchase
Agreement, dated March 3, 1997, as amended by Amendment No. 1 to Asset
Purchase Agreement, dated April 11, 1997 and now wish to further amend certain
of the provisions of the Asset Purchase Agreement.  Unless otherwise defined
herein, capitalized terms shall have the meanings given them in the Asset
Purchase Agreement

     NOW, THEREFORE, in consideration of the premises and of the mutual
covenants contained herein, the parties hereto agree to amend the Asset
Purchase Agreement as follows:

1.   Section 1.1 shall be amended by revising paragraphs B and C of the
definition of Purchase Price to read as follows:

     B.   A payment to the Plan in the amount of Five hundred thirty thousand
          nine hundred seventeen and No/100 ollars ($530,917.00), to be paid,
          without interest, as follows: $271,017.00 shall be paid to the Plan
          at Closing (the "Initial Plan Payment"); $34,900.00 shall be paid to
          the Plan no later than the first anniversary of the Closing Date;
          $162,500.00 shall be paid to the Plan no later than the second
          anniversary of the Closing Date; and $62,500.00 shall be paid to the
          Plan no later than the third anniversary of the Closing Date;

     C.   An assumption of liabilities of Seller to its Employees for
          liabilities of Seller to its Employees for accrued and unpaid
          vacation liabilities ("Vacation Liability") in an amount not to
          exceed Two Hundred Fifty-Five Thousand Two Hundred and No/100
          dollars ($255,200.00), to be paid or provided for by Purchaser to
          such Employees in accordance with the Purchaser's existing vacation
          policy as though such Vacation Liability had accrued under such
          policy.  The Purchaser shall make $127,600 of the Vacation Liability
          available to be used by Employees as of the Closing Date, with the
          balance of $127,600 to be credited to the Employees' Vacation
          accounts one year following the Closing Date.

2.   Except as modified by this Amendment No. 2, the Asset Purchase Agreement,
as amended by Amendment No. 1, remains in full force and effect.

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IN WITNESS WHEREOF, the parties hereto have caused this Agreement to be duly
executed on their respective behalf, by their respective officers thereunto
duly authorized, all as of the day and year first above written.

                                   SELLER:

                                   APPLIED RESEARCH OF MARYLAND INC.


                                   By _______________________ (Seal)

                                   Title: __________________________


                                   PURCHASER:

                                   SPACE APPLICATIONS CORPORATION


                                   By _______________________ (Seal)

                                   Title: __________________________


                                   OFFICIAL UNSECURED CREDITORS' COMMITTEE


                                   By ______________________________

                                   Title: __________________________



Agreed and consented to:           __________________________ (Seal)
                                   DR. S.P.S. ANAND