<PAGE>

AMENDED OCT 03, 1991                                                Exhibit 3.1
AMENDED MAR 02, 1994
AMENDED JAN 19, 1995
AMENDED JAN 24, 2003

                           AMENDED AND RESTATED BYLAWS
                        OF GENERAL KINETICS INCORPORATED

l.   The principal office of the Corporation shall be in the County of Fairfax,
     Commonwealth of Virginia or such other place as may be designated by the
     Board of Directors.

2.   The Corporation may also have an office at such other places as the Board
     of Directors may from time to time appoint or the business of the
     Corporation may require.

                             SHAREHOLDERS' MEETINGS

3.   All meetings of the shareholders shall be held at such place as may from
     time to time be fixed by the Board of Directors and which shall be stated
     in the notice of the meeting.

4.   The annual meeting of the shareholders of the Corporation shall be held at
     such time during the last quarter of each calendar year as the Board of
     Directors from time to time shall by resolution direct. At each such annual
     meeting, a Board of Directors shall be elected and such other business may
     be transacted as may properly be brought before the meeting.

5.   A written or printed notice of the annual meeting of shareholders shall be
     served upon or mailed to each shareholder entitled to vote thereat, at such
     address as appears on the books of the Corporation, at least ten days prior
     to the meeting or on or before such earlier date as the law may require.

6.   A special meeting of the shareholders for of the shareholders for any
     purpose or purposes may be called at any time by the Chairman of the Board
     or the President, by the Board of Directors, or by shareholders together
     holding at least 40% of the number of shares of the Corporation at the time
     outstanding and entitled to vote with respect to the business to be
     transacted at such meeting. At a special meeting no business shall be
     transacted and no corporate action shall be taken other than that stated in
     the notice of the meeting.

7.   Written or printed notice of a special meeting of the shareholders, stating
     the time, place and object thereof, shall be served upon or mailed to each
     shareholder entitled to vote

<PAGE>

     thereat at such address as appears on the books of the Corporation at least
     ten days before such meeting, or on or before such earlier date as the law
     may require.

8.   The holders of a majority in interest of the stock issued and outstanding#
     having voting power present in person or represented by proxy, shall be
     requisite and shall constitute a quorum at all meetings of the shareholders
     for the transaction of business, except as otherwise provided by statute,
     by the Articles of Incorporation, or by these Bylaws. If, however, a quorum
     shall not be present or represented at any meeting of the shareholders, the
     shareholders entitled to vote thereat present in person or represented by
     proxy shall have power by majority vote of those present in person or
     represented by proxy to adjourn the meeting from time to time, without
     notice other than announcement at the meeting, until a quorum shall be
     present or represented. At such adjourned meeting at which a quorum shall
     be present or represented, any business may be transacted which might have
     been transacted at the meeting as originally notified.

9.   When a quorum is present or represented at any meeting of shareholders# the
     vote of the holders of a majority of the stock having voting power, present
     in person or represented by proxy, shall decide any question brought before
     such meeting, unless the question is one upon which, by express provision
     of the statutes or of the Articles of Incorporation or of these Bylaws, a
     different vote is required, in which case such express provision shall
     govern and control the decision of such question. In the election of
     Directors, those receiving the greatest number of votes of those
     shareholders present or represented by proxy shall be deemed elected.

10.  At any meeting of the shareholders, every shareholder having voting power
     shall be entitled to vote in person or by proxy appointed by an instrument
     subscribed by such shareholder or by his duly authorized attorney-in-fact
     or other lawful representative and delivered to the secretary of the
     meeting. A proxy shall be revocable only in writing or by attendance by the
     shareholder in person at the meeting. Each shareholder shall have one vote
     for each share of stock having voting power registered in his name on the
     books of the Corporation on the date of the meeting or, if a record date
     shall have been fixed in advance of such meeting for the determination of
     the shareholders entitled to notice of and to vote at such meeting, then
     the determination of entitlement to vote shall be made based upon the date
     fixed as a record date. Upon majority vote of the shareholders present in
     person or represented by proxy, the vote on any question shall be by
     ballot.

<PAGE>

                                    DIRECTORS

ll.  (a) The number of Directors of the Corporation shall be not fewer than
     three nor more than eleven. The Board of Directors may determine the size
     of the Board from time to time, within the limits of the preceding
     sentence; except that if the number of Board members is established at a
     number greater than six, then the number of Directors who are employees of
     the Corporation ("Employee Directors") may not exceed one-third of the
     number of Directors constituting the whole Board, and in any other case,
     the number of Employee Directors may not exceed one-half of the number of
     Directors constituting the whole Board. The Board nay not increase the size
     of the Board by more than two between annual meetings of shareholders.

     (b) Any vacancy created by an increase in the Board pursuant hereto, up to
     a maximum of two such vacancies created between annual meetings of the
     shareholders, may be filled by a majority of Directors then in office.
     Directors so chosen shall hold office until their qualified successors have
     been duly elected by the shareholders at their regular meeting held for
     such purpose.

     (c) Any decrease in the Board of Directors pursuant to section a of this
     Article 11 shall not have the effect of shortening the term of any
     incumbent Director, nor shall any Director be disqualified for the sole
     purpose of maintaining the ratio limiting the number of Employee Directors.

     (d) All Directors of the Corporation shall be elected or chosen to serve
     until their successors have been duly elected or chosen and have qualified.

     (e) Directors need not be shareholders.

     (f) At the first meeting of each newly elected Board, the Board shall
     appoint a Chairman of the Board from among its members and may appoint a
     vice Chairman.

     (g) The Chairman of the Board shall preside at all meetings of the
     shareholders and all meetings of the Board of Directors at which he is
     present. The Chairman of the Board shall, in the absence or disability of
     the President, perform the duties and exercise the powers of the President.
     He shall carry out such other duties as may be assigned by the Board of
     Directors, including, but not limited to, supervisory management duties.
     The Chairman shall be an ex officio member of all committees of which he is
     not a member.            -- -------


<PAGE>

12.  The Directors may hold their meetings and keep the books of the corporation
     at such place or places as they may from time to time determine.

13.  If the office of any Director or Directors becomes vacant by reason of
     death, resignation, retirement, disqualification, or from any other cause
     other than removal by the shareholders, the Directors then in office, by a
     majority vote, may choose a successor or successors, who shall hold office
     for the unexpired term in respect of which such vacancy occurred. The
     shareholders at a meeting expressly called for that purpose may, by
     affirmative vote of shareholders holding a majority of the shares having
     voting power represented in person or by proxy at such meeting, remove any
     Director and fill the vacancy caused by such removal.

14.  The Board of Directors may exercise all such powers of the Corporation and
     do all such lawful acts and things as are not by statute or by the Articles
     of Incorporation or by these Bylaws directed or required to be exercised or
     done by the shareholders.

                             COMMITTEES OF DIRECTORS

15.  The Board of Directors may, by resolution passed by a majority vote of the
     Board, designate two or more of their number to constitute an Executive
     Committee, who shall consult with and advise the officers of the
     Corporation in all matters concerning the interests of the Corporation and
     the management of its business and affairs and exercise such powers of the
     Board of Directors as may be lawfully delegated by the Board of Directors,
     including the power to authorize the seal of the Corporation to be affixed
     to any papers requiring a seal. The Executive Committee shall consist of no
     fewer than two outside Directors for each Employee Director. It may meet at
     stated times, or on notice to all members of the Committee by any member
     thereof, and shall keep regular minutes of its proceedings and report the
     same to the Board when required. Vacancies in the membership of the
     Executive Committee shall be filled by the Board of Directors.

16.  The Board of Directors may by majority vote of the Board designate other
     committees, each committee to consist of two or more outside Directors to
     each Employee Director. Each such committee shall have and exercise, to the
     extent provided by resolution of the Directors, such powers of the Board of
     Directors in the management of the business and affairs of the Corporation
     as may be lawfully delegated.

<PAGE>

                            COMPENSATION OF DIRECTORS

17.  Directors, as such, shall not receive any stated salary for their service,
     but, by resolution of the Board of Directors, may be compensated by a
     combination of (i) fixed amounts determined by the board and/or the
     appropriate Stock Option Plans, and (ii) incentive amounts tied to
     performance measures such as (but not limited to) profitability and
     increases in stock price, as established by the Board and/or the
     appropriate Stock Option Plans. In addition, Directors may be reimbursed
     for expenses of attendance at each regular or special meeting of the Board
     or any meeting of any committee, regardless of whether such attendance is
     in person or by conference call. Nothing contained in this Article 17 shall
     be construed to preclude any Director from serving the corporation in any
     other capacity and receiving compensation therefor.

                              MEETINGS OF THE BOARD

18.  The first meeting of each newly elected Board shall be held at the same
     place as, and immediately after the conclusion of, the annual meeting of
     shareholders, unless otherwise determined either by vote of the
     shareholders at the annual meeting or by the unanimous consent in writing
     of all such newly elected Directors. No notice of such meeting to the newly
     elected Directors shall be necessary to constitute the meeting provided a
     quorum shall be present. Regular meetings of the Board may be held without
     notice at such time and place as shall from time to time be determined by
     the Board.

19.  Special meetings of the Board may be called by the Chairman of the Board on
     five days notice to each Director, either personally, by mail, by facsimile
     transmission, or by telegram. Personal notice shall be confirmed by mail,
     facsimile or telegram no less than two days prior to the meeting date.
     Special meetings shall be called by the Chairman of the Board in like
     manner and on like notice, upon the written request of two Directors. In
     the event that the time delay required by this Article would not be in the
     best interest of the Corporation, the Chairman of the Board may personally
     or at the direction by two Directors, call a meeting on twenty-four hours
     notice using any means of communication that would normally convey the
     notice and if a quorum is present at the meeting, it shall be deemed to
     have been properly called and convened.

20.  At all meetings of the Board, the presence at a majority of the Directors
     shall be necessary and sufficient to constitute a quorum for the
     transaction of business, and the act of a majority of the Directors present
     at any meeting at which there is a quorum shall be the act of the Board of
     Directors, except as may be otherwise specifically provided by statute or
     by the

<PAGE>

     Articles of Incorporation or by these Bylaws. Attendance at any meeting of
     the Board may to the extent permitted by law, be by conference call. If a
     quorum shall not be present at any meeting of Directors, the Directors
     present thereat may by majority vote adjourn the meeting from time to time
     without notice other than announcement at the meeting, until a quorum shall
     be present.

                                     NOTICES

21.  Whenever under the provisions of the statutes or of the Articles of
     Incorporation or of these Bylaws, notice is required to be given to any
     Director or shareholder, it shall not be construed to mean personal notice,
     but such notice may be given in writing, by mail or by facsimile
     transmission, addressed to such Director or shareholder at such address as
     appears on the books of the Corporation, and such notice shall be deemed to
     be given at the time when the same shall be thus mailed, sent by facsimile
     transmission, or sent by telegram.

22.  Whenever any notice is required to be given to a Director by law or by the
     Articles of Incorporation or these Bylaws, a waiver thereof in writing
     signed by the person or persons entitled to said notice, before or at the
     time stated in such notice, or, in the case of a Meeting, the attendance of
     the Director, in person or by conference telephone, shall be deemed
     equivalent thereto.

23.  (a) The officers of the Corporation shall be elected by the Directors and
     shall be a President, a Secretary and a Treasurer. The Board of Directors
     may also appoint one or more Vice Presidents and one or more Assistant
     Secretaries and Assistant Treasurers. Two or more offices may be held by
     the same person, except those of (i) President and Vice President, and (ii)
     President and Secretary.

     (b) The Board of Directors, at its first meeting after each annual meeting
     of shareholders, shall choose a President, a Secretary, a Treasurer, and
     such other officers as the Board shall deem necessary and appropriate.
     Except for the President, none of the officers of the Corporation need be a
     member of the Board of Directors.

24.  The Board may appoint such other officers and agents as it shall deem
     necessary, who shall hold their offices for such terms and shall exercise
     such authority and shall perform such duties as from time to time shall be
     prescribed by the Board. The salaries of the President and of any other
     officer who is also a Director of the corporation shall be fixed by the
     Board of Directors. The salaries of all other officers and agents of

<PAGE>

     the Corporation may be fixed by the president with the consent of the
     Board.

25.  The officers of the Corporation shall hold office for one year or until
     their successors are elected and qualify. Any officer elected or appointed
     by the Board of Directors may be removed at any time by the Board of
     Directors. If the office of any officer elected or consented to by the
     Board of Directors becomes vacant for any reason, the vacancy shall be
     filled by the Board of Directors.

                                    PRESIDENT

26.  (a) The president shall be responsible for general and active management of
     business affairs of the Corporation and shall see that all orders and
     resolutions of the Board are carried out. The President shall be an ex
     officio member of all committees of which he is not a member. The President
     shall preside at all meetings of both the shareholders and the Board of
     Directors at which he is present when neither the Chairman or Vice Chairman
     are present.

     (b) He shall execute bonds, mortgages and other contracts requiring a seal,
     under the seal of the Corporation, except where required or permitted by
     law to be otherwise signed and executed and except where the signing and
     execution thereof shall be expressly delegated by the Board of Directors to
     some other officer or agent of the Corporation.

                                 VICE PRESIDENTS

27.  Vice Presidents, including Senior and Executive Vice Presidents, shall, in
     accordance with procedures established by the President, with the
     concurrence of the Board of Directors, perform the duties and exercise the
     powers assigned by the President, and shall perform such other duties as
     the Board of Directors shall from time to time prescribe.

                       SECRETARY AND ASSISTANT SECRETARIES

28.  The Secretary shall attend all sessions of the Board and all meetings of
     the shareholders and record all votes and the minutes of all proceedings in
     a book to be kept for that purpose and shall perform like duties for the
     Executive Committee or other standing committees when requested. The
     Secretary shall keep a register of the address of each

<PAGE>

     shareholder and make all proper changes in such register, retaining and
     filing his authority for all such entries. He shall give, or cause to be
     given, notice of all meetings of the shareholders and special meetings of
     the Board of Directors, and shall perform such other duties as may be
     prescribed by the Board of Directors or President, under whose supervision
     he shall be. He shall keep in safe custody the seal of the Corporation,
     and, when authorized by the Board, shall affix the same to any instrument
     requiring a seal and, when so affixed, it shall be attested by his
     signature or by the signature of the Treasurer or an Assistant Secretary.

29.  The Assistant Secretaries, in the order of their seniority, shall, in the
     absence or disability of the Secretary, perform the duties and exercise the
     powers of the Secretary and shall perform such other duties as the Board of
     Directors shall prescribe.

                        TREASURER AND ASSISTANT TREASURER

30.  The Treasurer shall have the custody of the corporate-funds and securities
     and shall keep full and accurate accounts of receipts and disbursements in
     books belonging to the Corporation, and shall deposit all moneys and other
     valuable effects in the name and to the credit of the Corporation in such
     depositories as may be designated by the Board of Directors.

31.  The Treasurer shall disburse funds of the Corporation as may be ordered by
     the Board, taking proper vouchers for such disbursements, and shall render
     to the President and Directors, at the regular meetings of the Board, or
     whenever they may require it, an account of all his transactions as
     Treasurer and of the financial condition of the Corporation.

32.  If required by the Board of Directors, the Treasurer shall give the
     Corporation a bond in such surety or sureties as shall be satisfactory to
     the Board for the faithful performance of the duties of his office and for
     the restoration to the corporation in case of death, resignation,
     retirement or removal from office, of all books, papers, vouchers, money
     and other property of whatever kind in the Treasurer's possession or under
     his control belonging to the Corporation.

33.  The Assistant Treasurers in the order of their seniority shall, in the
     absence or disability of the Treasurer, perform the duties and exercise the
     powers of the Treasurer and shall perform such other duties as the Board of
     Directors shall prescribe.

<PAGE>

                              CERTIFICATES OF STOCK

34.  The certificates of stock of the Corporation shall be numbered and entered
     in the books of the Corporation as they are issued. They shall exhibit the
     holder's name and the number of shares owned, shall bear the corporate seal
     and shall be signed by the President, or one of the Vice Presidents, and
     the Treasurer or by any two officers authorized by the Board of Directors,
     but where any such certificate is signed by a transfer agent or transfer
     clerk and by a registrar, the signatures of any of the officers and the
     seal of the Corporation upon such certificate may be facsimile, engraved or
     printed.

                                LOST CERTIFICATE

35.  The Board of Directors may direct a new certificate or certificates to be
     issued in place of any certificate or certificates theretofore issued by
     the Corporation alleged to have been lost or destroyed, upon the making of
     an affidavit of that fact by the person claiming the certificate of stock
     to be lost or destroyed. When authorizing such issue of a new certificate
     or certificates, the Board of Directors may, in its discretion, as a
     condition precedent to the issuance thereof, require the owner of such lost
     or destroyed certificate or certificates, or his legal representatives, to
     advertise the same in such manner as it shall require and/or to give the
     Corporation a bond in such sum as it may direct, not exceeding double the
     value of the stock, to indemnify the Corporation against any claim that may
     be made against the Corporation with respect to the certificate alleged to
     have been lost or destroyed.

                               TRANSFERS OF STOCK

36.  Upon surrender to the corporation or to the transfer agent of the
     Corporation of a certificate for shares duly endorsed or accompanied by
     proper evidence of succession, assignment or authority to transfer, it
     shall be the duty of the corporation to issue a new certificate to the
     person entitled thereto, cancel the old certificate and record the
     transaction upon its books.

                              FIXING OF RECORD DATE

37.  The Board of Directors may fix in advance a date not less than ten nor more
     than seventy days preceding the date of any

<PAGE>

     meeting of shareholders or the date for the payment of any dividend, or the
     date for the allotment of rights, or the date when any change or conversion
     or exchange of capital stock shall go into effect, as a record date for the
     determination of the shareholders entitled to notice of and to vote at any
     such meeting, or entitled to receive payment of any such dividend, or to
     any such allotment of rights, or to exercise the rights in respect of any
     such change, conversion or exchange of capital stock, and, in such case,
     such shareholders, and only such shareholders as shall be shareholders of
     record on the date so fixed, shall be entitled to such notice of, and to
     vote at, such meeting or to receive payment of such dividend, or to receive
     such allotment of rights, or to exercise such rights, as the case may be,
     notwithstanding any transfer of any stock in the books of the Corporation
     after any such record date fixed as aforesaid.

                             REGISTERED SHAREHOLDERS

38.  The Corporation shall be entitled to treat the holder of record of any
     share or shares of stock as the holder in fact thereof, and, accordingly,
     shall not be bound to recognize any equitable or other claim to or interest
     in such share on the part of any other person, and shall not be liable for
     registering any transfer of shares that are registered in the name of a
     fiduciary unless made with actual knowledge that the fiduciary is
     committing a breach of his obligation as fiduciary in making the transfer,
     or with knowledge of such facts that its action in registering the transfer
     amounts to bad faith.

                                    DIVIDENDS

39.  Dividends on the shares of the capital stock of the Corporation, subject to
     the provisions of the Articles of Incorporation, if any, may be declared by
     the Board of Directors at any regular or special meeting, pursuant to law.
     Dividends may be paid in cash, in property, or in shares of the capital
     stock of the Corporation, subject to any provisions with respect thereto in
     the Articles of Incorporation.

40.  Before payment of any dividend, there may be set aside out of any funds of
     the Corporation available for dividends such sum or sums as the Directors
     from time to time, in their absolute discretion, think proper as a reserve
     fund to meet contingencies, or for equalizing dividends, or for repairing
     or maintaining any property of the Corporation, or for such other purpose
     as the Directors shall think conducive to the interest of the Corporation,
     and the Directors may modify or abolish any such reserve in the manner in
     which it was created.

<PAGE>

                                     CHECKS

41.  All checks or demands for money and notes of the Corporation shall be
     signed by such officer or officers or such other person or persons as the
     Board of Directors may from time to time designate.

                                   FISCAL YEAR

42.  The fiscal year shall be determined by resolution of the Board or
     Directors.

                                   AMENDMENTS

43.  These Bylaws may be altered or amended or repealed at any regular meeting
     of the shareholders or at any special meeting of the shareholders at which
     a quorum is present or represented, provided notice of the proposed
     alteration or amendment or repeal is contained in the notice of such
     Special meeting, by the affirmative vote of a majority of the Board of
     Directors at any regular meeting of the Board, or at any special meeting of
     the Board it notice of the proposed alteration or repeal is contained in
     the notice of such special meeting. Bylaws so made by the Directors may be
     altered or repealed by the sharcho1ders.

                      INSPECTION OF RECORDS BY SHAREHOLDERS

44.  Any person who has been a shareholder of record for at least six months or
     who owns at least five percent all the outstanding shares of the
     corporation, shall have the right to examine, at the office of the
     Corporation, in person or by agent or attorney, at any reasonable time or
     times, for any proper purpose, its books and records of account, minutes
     and record of shareholders, and to make extracts therefrom. Any shareholder
     who desires to exercise such right shall make written request therefor to
     the President or Secretary of the Corporation, stating the information
     desired, the person or persons to whom the information or records should be
     made available by the Corporation, and the time proposed not less than five
     (5) days from the date of the request for visiting the offices of the
     Corporation for this purpose. Upon the written request of any shareholder,
     the Corporation shall mail to such shareholder its most recently prepared
     financial statements showing its assets and liabilities and the results of
     its operations.

<PAGE>

                                      SEAL

45.  The corporate seal shall have inscribed thereon the name of the
     Corporation, the year of its organization and the words, "Corporate Seal,
     Virginia."

                    INDEMIFICATION OF OFFICERS AND DIRECTORS

46.  The Corporation shall, to the fullest extent authorized or permitted by the
     Virginia Stock Corporation Act, indemnify any person who is or was a
     Director or officer of the Corporation, or any person who acts or has acted
     as an officer of Director of any other corporation at the request of the
     corporation, against any and all expenses (including attorneys' fees),
     costs, judgments, settlements, fines or liabilities incurred by such person
     in connection with any threatened, pending or completed action, suit or
     investigation to which such person is or was a party or is threatened to be
     made a party by reason of the fact that such person was or is such a
     Director or officer.

47.  Except as otherwise provided by the Virginia Stock Corporation Act, in any
     proceeding brought by a shareholder in the right of the Corporation or
     brought by or on behalf of the shareholders of the Corporation, the damages
     assessed against an officer or Director arising out of a single
     transaction, occurrence or course of conduct shall not exceed ten dollars
     ($10.00).

                   APPLICATION OF CERTAIN STATUTORY PROVISIONS

48.  Article 14.1 of the Virginia Stock Corporation Act (including ss. 13.1 -
     728.1 - 728.9 thereof) and any successor thereto shall not apply to
     acquisitions of shares of the corporation.