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                                                                     Exhibit 3.4


                                MATEC Corporation

                        By-Laws - effective May 18, 2000

                                    ARTICLE I
                                     OFFICES

                  Section 1. Offices. The Corporation shall maintain a
registered office in Maryland. The Corporation may maintain such other offices
and keep its books, documents and records at such other places both within and
without the State of Maryland as the Board of Directors may from time to time
determine or the business of the Corporation may require.

                                   ARTICLE II
                                  STOCKHOLDERS

                  Section 2. Annual Meetings. An annual meeting of stockholders
for the election of directors and the transaction of such other business as may
properly come before the meeting shall be held in May on such date and at such
time as the Board of Directors each year shall fix.

                  Section 3. Notice of Annual Meeting. Written or printed notice
of the annual meeting stating the place, date and hour of the meeting shall be
delivered not less than ten nor more than ninety days before the date of the
meeting, by mail, by or at the direction of the chief executive officer, the
Secretary, or the officer or persons calling the meeting, to each stockholder of
record entitled to vote at such meeting.

                  Section 4. Special Meetings. Special meetings of the
stockholders, for any purpose or purposes, unless otherwise prescribed by
statute or by the Articles of Incorporation, may be called by the chief
executive officer or the Board of Directors. The business transacted at any
special meeting of stockholders shall be limited to the purposes stated in the
notice of the meeting.


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                  Section 5. Notice of Special Meetings. Written or printed
notice of a special meeting stating the place, date and hour of the meeting and
the purpose or purposes for which the meeting is called, shall be delivered not
less than ten nor more than ninety days before the date of the meeting, by mail,
by or at the direction of the chief executive officer, the Secretary, or the
officer or persons calling the meeting, to each stockholder of record entitled
to vote at such meeting. The notice shall also indicate that it is being issued
by, or at the direction of, the person calling the meeting.

                  Section 6. Quorum. The holders of a majority of the shares
issued and outstanding and entitled to vote, represented in person or by proxy,
shall constitute a quorum at all meetings of the stockholders for the
transaction of business except as otherwise provided by statute or by the
Articles of Incorporation. If, however, such quorum shall not be present or
represented at any meeting of the stockholders, the stockholders present in
person or represented by proxy shall have power 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 noticed.

                  Section 7. Voting. At any meeting of stockholders each
outstanding share having voting power shall be entitled to one vote on each
matter submitted to a vote. A stockholder may vote either in person or by proxy
executed in writing by the stockholder or by his duly authorized
attorney-in-fact. All elections shall be determined by plurality vote, and
except as otherwise provided by statute or in the Articles of Incorporation, all
other matters shall be determined by vote of a majority of the shares present or
represented at such meeting and voting on such matters.


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                  Section 8. Inspectors of Election. The Board of Directors in
advance of any meeting of stockholders may appoint one or more inspectors to act
at the meeting or any adjournment thereof. If inspectors are not so appointed,
the person presiding at a meeting of stockholders may, and, on the request of
any stockholder entitled to vote thereat, shall appoint one or more inspectors.
In case any person appointed as inspector fails to appear or act, the vacancy
may be filled by the Board of Directors in advance of the meeting or at the
meeting by the person presiding thereat. Each inspector, before entering upon
the discharge of his duties shall take and sign an oath faithfully to execute
the duties of inspector at such meeting with strict impartiality and according
to the best of his ability.

                  Section 9. List of Stockholders. A list of stockholders as of
the record date, certified by the officer of the Corporation responsible for its
preparation or by the transfer agent, shall be produced at any meeting of
stockholders upon the request thereat or prior thereto of any stockholder. If
the right to vote at any meeting is challenged, the inspectors of election, or
person presiding thereat shall require such list of stockholders to be produced
as evidence of the right of the persons challenged to vote at such meeting, and
all persons who appear from such list to be stockholders entitled to vote
thereat may vote at such meeting.

                                   ARTICLE III
                                    DIRECTORS

                  Section 1. Number, Qualification and Term. The property and
business of the Corporation shall be managed by its Board of Directors
consisting of not less than Five (5) nor more than Thirteen (13) persons. The
number of directors constituting the entire Board shall be Nine(9); provided,
however, that from time to time, such number may be decreased to not less than
Five (5) or increased to not more than Thirteen (13) persons by amendment of
this section of the By-laws by a majority of the entire Board of Directors.
Directors need not be stockholders. They shall be elected at the Annual Meeting
of Stockholders and each director shall be elected to serve until his successor
shall be elected and shall qualify.


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                  Section 2. Removal. Any or all of the directors may be removed
for cause at any time by the vote of the stockholders.

                  Section 3. Any vacancy occurring in the Board of Directors for
any cause other than by reason of an increase in the number of directors may be
filled by a majority of the remaining members of the Board of Directors,
although such majority is less than a quorum. Any vacancy occurring by reason of
an increase in the number of directors may be filled by action of a majority of
the entire Board of Directors. A director elected by the Board of Directors to
fill a vacancy shall be elected to hold office until the next annual meeting of
stockholders or until his successor is elected and qualifies.

                  Section 4. Additional Powers. In addition to the powers and
authorities by these By-Laws expressly conferred upon it, 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
By-Laws directed or required to be exercised or done by the stockholders.

                                   ARTICLE IV
                       MEETINGS OF THE BOARD OF DIRECTORS


                  Section 1. Place. Meetings of the Board of Directors, regular
or special, may be held either within or without the State of Maryland.

                  Section 2. First Meeting. The first meeting of each newly
elected Board of Directors shall be held immediately after the annual meeting of
stockholders at the same place as such meeting is held and no notice of such
meeting to the newly elected directors shall be necessary in order legally to
constitute the meeting provided a quorum shall be present, or it may convene at
such place and time as shall be specified in a notice given as hereinafter
provided for special meetings of the Board of Directors, or as shall be
specified in a duly executed waiver of notice thereof.


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                  Section 3. Regular Meetings. Regular meetings of the Board of
Directors may be held upon such notice, or without notice, and at such time and
at such place as shall from time to time be determined by the Board.

                  Section 4. Special Meetings. Special meetings of the Board of
Directors may be called by the chief executive officer on written notice to each
director, deposited in the United States mail no later than the third calendar
day preceding the meeting date or delivered by hand or to the telegraph company
no later than the first calendar day preceding the meeting date; special
meetings shall be called by the chief executive officer or Secretary in like
manner and on like notice on the written request of two directors.

                  Section 5. Quorum. A majority of the entire Board of Directors
shall constitute a quorum for the transaction of business unless a greater or
lesser number is required by law or by the Articles of Incorporation. The vote
of a majority of the directors present at any meeting at which a quorum is
present shall be the act of the Board of Directors, unless the vote of a greater
number is required by law or by the Articles of Incorporation. If a quorum shall
not be present at any meeting of directors, the directors present may adjourn
the meeting from time to time. Notice of any such adjournment shall be given to
any director who was not present at the time of such adjournment and unless
announced at the meeting to the other directors.

                  Section 6. Consent in Lieu of Meeting. Any action required or
permitted to be taken by the Board of Directors or any committee thereof may be
taken without a meeting if all members of the Board or the committee consent in
writing to the adoption of a resolution authorizing the action. The resolution
and the written consents thereto by the members of the Board or committee shall
be filed with the minutes of the proceedings of the Board or committee.


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                  Section 7. Telephone Participation at Meetings. Any one or
more of the Board of Directors or any committee thereof may participate in a
meeting of the Board of Directors or of such committee by means of conference
telephone or similar communications equipment allowing all persons participating
in the meeting to hear each other at the same time. Participation in a meeting
by such means shall constitute presence in person at a meeting.

                                    ARTICLE V
                                   COMMITTEES

                  Section 1. Committees. The Board of Directors, by resolution
adopted by a majority of the entire board, may designate, from among its
members, an executive committee and other committees consisting of three or more
directors, which, to the extent provided in the resolution, shall have all the
authority of the Board, except as otherwise required by law. Vacancies in the
membership of such committees shall be filled by the Board of Directors at a
regular or special meeting. Such committees shall keep regular minutes of its
proceedings and report the same to the Board when required.

                  Subject to the provisions of these By-Laws, the executive
committee and each other committee shall fix its own rules of procedure and
shall meet as provided by such rules or by resolution of the Board of Directors
and it shall also meet at the call of the Chairman of the Board or President of
the Corporation or any two members of such committee. A majority of the
executive committee and of each other committee shall constitute a quorum for
the transaction of business and the vote of a majority of the members of such
committee present at any meeting at which there is a quorum shall be the act of
such committee.


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                                   ARTICLE VI

                                     NOTICES

                  Section 1. Form; Delivery. Whenever, under the provisions of
the statutes or of the Articles of Incorporation or of these By-Laws, notice is
required to be given to any director or stockholder, such notice may be given in
writing, by mail, addressed to such director or stockholder, at his address as
it appears on the records of the Corporation, with postage thereon prepaid, and
such notice shall be deemed to be given at the time when the same shall be
deposited in the United States mail. Notice to directors may also be given by
hand delivery, effective upon such delivery, or by telegram which notice shall
be deemed to have been given when delivered to the telegraph company. Neither
the business to be transacted at, nor the purpose of, any regular or special
meeting of the Board of Directors need be specified in the notice or waiver of
notice of such meeting.

                  Section 2. Waiver of Notice. Whenever any notice is required
to be given under the provisions of any statute or under the provisions of the
Articles of Incorporation or these By-Laws, a waiver thereof in writing signed
by the person or persons entitled to such notice, whether before or after the
time stated therein, shall be deemed equivalent to the giving of such notice. In
addition, any stockholder attending a meeting of stockholders in person or by
proxy without protesting prior to the conclusion of the meeting, the lack of
notice thereof to him, and any director attending a meeting of the Board of
Directors without protesting prior to the meeting or at its commencement such
lack of notice shall be conclusively deemed to have waived notice of such
meeting.

                                   ARTICLE VII
                               OFFICERS AND AGENTS


                  Section 1. Officers. The officers of the Corporation shall be
chosen by the Board of Directors and shall be a Chairman of the Board, a
President, a Vice-President, a Secretary and a Treasurer. The Board of Directors
may also choose additional Vice-Presidents, and one or more Assistant
Secretaries and Assistant Treasurers.


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                  Section 2. Election. The Board of Directors at its first
meeting after each annual meeting of stockholders shall choose a Chairman of the
Board, a President, one or more Vice-Presidents, a Secretary and a Treasurer.
Any two or more offices may be held by the same person.

                  Section 3. Additional Officers and Agents. The Board of
Directors may appoint such other officers and agents as it shall deem necessary
who shall hold their offices for such terms and shall exercise such powers and
perform such duties as shall be determined from time to time by the Board of
Directors.

                  Section 4. Compensation. The salaries of all officers of the
Corporation shall be fixed by the Board of Directors and the compensation of
employees and agents shall be so fixed or shall be fixed by officers thereunto
duly authorized.

                  Section 5. Term of Office; Removal. The officers of the
Corporation shall hold office until their successors are chosen and qualify. Any
officer or agent elected or appointed by the Board of Directors may be removed
at any time with or without cause by the Board. Any vacancy occurring in any
office of the Corporation may be filled by the Board of Directors.

                  Section 6. Powers and Duties of the Chairman of the Board. The
Chairman of the Board of Directors shall preside at all meetings of the Board
and all meetings of the stockholders at which he shall be present and shall have
such other powers and duties as may from time to time be assigned to him by the
Board of Directors.

                  Section 7. Powers and Duties of the President. The President
shall be the Chief Executive Officer of the Corporation, and shall have the
general management and superintendence of the affairs of the Corporation,
subject, however, to the control of the Board of Directors; and in all cases
where, and to the extent that, the duties of the other officers of the
Corporation are not specifically prescribed by By-Laws or rules or regulations
of the Board of Directors, the President may prescribe such duties. He shall
have general and active supervision over the property, business and affairs of
the Corporation and may sign, execute, and deliver in the name of the
Corporation deeds, mortgages, bonds, contracts, powers of attorney, and other
instruments, except in cases where the signing and


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execution thereof shall be expressly delegated by the Board of Directors or
these By-Laws to some other officer or agent of the Corporation or shall be
required by law or otherwise to be signed or executed, and may exercise any and
all powers and perform any and all duties relating to such supervision, or which
are imposed upon him by the By-Laws, or by the Board of Directors.

                  Subject to such limitations as the Board of Directors may from
time to time prescribe, the Chief Executive Officer shall have power to appoint
and to dismiss all such agents and employees of the Corporation who are not
officers thereof (including any appointed by the Board) as he may deem proper,
and to prescribe their duties, and subject to like limitations, delegate to
other officers of the Corporation any other of the powers and duties conferred
upon him by the By-Laws or by the Board of Directors.

                  Section 8. Powers and Duties of the Vice President. The
Vice-President shall perform the duties as may be prescribed by the Board of
Directors and subject to the chief executive officer.

                  Section 9. Powers and Duties of the Secretary. The Secretary
shall attend all sessions of the Board and all meetings of the stockholders 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 any committee of the Board when
required. He shall cause to be given notice of all meetings of stockholders and
directors and shall perform such other duties as pertain to his office. He shall
keep in safe custody the seal of the Corporation and when authorized by the
Board of Directors, affix it when required to any instrument.

                  Section 10. Powers and Duties of the Treasurer. The Treasurer
shall have the custody of all 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. He shall disburse the funds of the
Corporation as may be ordered by the Board, taking proper vouchers for such
disbursements, and shall render to the chief executive officer and directors at
the regular meetings of the Board, or whenever they may require it, an


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account of all his transactions as treasurer and of the financial condition of
the Corporation.

                  Section 11. Powers and Duties of Other Officers. All other
officers shall have such duties and exercise such powers as generally pertain to
their respective offices and all officers shall have such other duties and
exercise such other powers as from time to time may be prescribed by the chief
executive officer or the Board of Directors.

                                  ARTICLE VIII
                                     SHARES

                  Section 1. Form; Signature. The shares of the Corporation
shall be represented by certificates signed by the President or a Vice-President
and the Secretary or an Assistant Secretary or the Treasurer or an Assistant
Treasurer of the Corporation and may be sealed with the seal of the Corporation
or a facsimile thereof. The signatures of the officers of the Corporation upon a
certificate may be facsimiles if the certificate is countersigned by a transfer
agent or registered by a registrar other than the Corporation itself or an
employee of the Corporation. In case any officer who has signed or whose
facsimile signature has been placed upon a certificate shall have ceased to be
such officer before such certificate is issued, it may be issued by the
Corporation with the same effect as if he were such officer at the date of
issue.

                  Section 2. Lost Certificates. The Board of Directors may
authorize the officers or agents of the Corporation to issue a new certificate
in place of any certificate theretofore issued by the Corporation alleged to
have been lost or destroyed and as a condition precedent to the issuance
thereof, may prescribe such terms and conditions as it deems expedient, and may
require such indemnities as it deems adequate to protect the Corporation from
any claim that may be made against it with respect to any such certificate
alleged to have been lost or destroyed.

                  Section 3. Transfer of Shares. Upon surrender to the
Corporation or the transfer agent of the Corporation of a certificate
representing shares duly endorsed or accompanied by proper evidence of
succession, assignment or


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authority to transfer, a new certificate shall be issued to the person entitled
thereto, and the old certificate cancelled and the transaction recorded upon the
books of the Corporation.

                  Section 4. Fixing Record Date. For the purpose of determining
stockholders entitled to notice of or to vote at any meeting of stockholders or
any adjournment thereof, or to express consent to or dissent from any proposal
without a meeting, or for the purpose of determining stockholders entitled to
receive payment of any dividend or the allotment of any rights, or for the
purpose of any other action, the Board of Directors may fix, in advance, a date
at the record date for any such determination of stockholders. Such date shall
not be more than sixty nor less than ten days before the date of any meeting nor
more than sixty days prior to any other action. When a determination of
stockholders of record entitled to notice of or to vote at any meeting of
stockholders has been made as provided in this section, such determination shall
apply to any adjournment thereof, unless the Board fixes a new record date for
the adjourned meeting.

                  Section 5. Registered Stockholders. The Corporation shall be
entitled to recognize the exclusive right of a person registered on its books as
the owner of shares to receive dividends, and to vote as such owner, and to hold
liable for calls and assessments a person registered on its books as the owner
of shares, and shall not be bound to recognize any equitable or other claim to
or interest in such share or shares on the part of any other person, whether or
not it shall have express or other notice thereof, except as otherwise provided
by the laws of Maryland.

                                   ARTICLE IX
                               GENERAL PROVISIONS


                  Section 1. Dividends. Subject to the provisions of law and of
the Articles of Incorporation relating thereto, dividends may be declared by the
Board of Directors at any regular or special meeting, pursuant to law. Dividends
may be paid in cash, the Corporation's bonds or its property, including the
shares or bonds of other corporations, subject to any provisions of law and of
the Articles of Incorporation.


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                  Section 2. Reserves. 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 purposes 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.

                  Section 3. Checks. 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.

                  Section 4. Fiscal Year. The fiscal year of the Corporation
shall begin on January 1st and end on December 31st of each year, unless
otherwise provided by the Board of Directors.

                  Section 5. Seal. The corporate seal shall have inscribed
thereon the name of the Corporation, the year of its organization and the words
"CORPORATE SEAL, MARYLAND". This seal may be used by causing it or a facsimile
thereof to be impressed or affixed or in any manner reproduced.

                                    ARTICLE X
                                   AMENDMENTS

                  Section 1. Amendments. The Board of Directors shall have the
exclusive power to adopt, alter or repeal any provision of these Bylaws and to
make new Bylaws.


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