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					          Ohio State
   ENGINEER
    The
          Vol. 87 No. 2 Winter ‘04




Saving Heritage: Columbus




                                                          Plus:
                                                          Superconductivity
                                                          A History of Lego
                                 Winter 2004
                                                          Great Feats: Paris
                                               The Ohio State Engineer         1
                                FROM THE EDITOR
       GETTING REAL: A REALITY SHOW
               THAT TEACHES
           A simple hand gesture and a simple phrase      objective was to earn money by running a pedicab
    hooked me in—you’re fired. I have finally fallen      service in New York City. The winning team sold
    into the reality show craze. I can honestly say       advertisements on each pedicab while the other team
    that I never thought I would religiously watch a      focused on earning their money solely through rides
    show, let alone a reality show. Maybe it was          fares. As an engineer, you must often think creatively
    fighting for a high profile job instead of a tanned   outside the norm when you are researching, experi-
    buxom beauty or a wad of cash that intrigued this     menting, or debugging in order to achieve the goal.
    weary engineering student. Maybe it was just          That is really how inventions are born and patents are
    The Donald. I often rolled my eyes at my              created.
    female friends whom you would think would                       Other important characteristics in successful
    give up their firstborns to see the next episode of   people are also highlighted on the show. Cast mem-
    The Bachelor. However, I am the one patiently         bers have bickered with one another about integrity,
    anticipating a reality show every Thursday night.     work ethic, and negotiation skills. Engineers have to
    The Apprentice has reeled me in, and I have no        negotiate their salaries, who can use what equipment
    means of escaping. However, unlike many               when, etc., while working hard with integrity. Team-
    reality television shows, NBC’s latest reality        work is essential for the success of any corporation
    contest can actually benefit the couch potato         and internal strife can be devastating to productivity.
    watching at home.                                     On this show, your degree or degrees are metaphori-
           In each episode, two teams of driven           cally thrown out the window as people with MBAs,
    individuals partake in a contest for billionaire      medical doctorates, and engineering degrees have
    mogul, Donald Trump. These tasks assess the           been fired because they did not have the characteris-
    sales, management, negotiation, and marketing         tics it takes to be a President of a Trump-owned
    skills of each player, while also forcing them to     company. Actually, the only person with an engineer-
    work as a cohesive team to win the task. Each         ing background on the show was fired by The Donald
    team appoints a Project Manager that will lead        because she did not stick up for herself when she was
    the group, often taking the blame for a failure or    the project manager on a losing team.
    the basking in the glory for a triumph. The jobs                Not only do I feel the show can be beneficial,
    include selling lemonade, renovating and renting      but so do others. Eugene Muscat, a senior associate
    an apartment, negotiating prices of merchandise,      dean of the University of San Francisco’s School of
    and managing a restaurant. I know what you are        Business and Management stated, “I think Donald
    thinking. “I’m an engineer, and I don’t plan on       Trump might be giving some feedback that just might
    working in sales or management.” Well, hold on        be valuable,” in a recent interview in The Kansas City
    there my pocket-protector-wearing comrade, but        Star. Watching this reality show may help you im-
    the skills and ideas that The Apprentice will help    prove your skills in the workplace, and maybe, one
    you in wherever you are going to work, whether        day you’ll find an ambitious young Ohio State electri-
    the boardroom, the test floor, or the lab.            cal engineering graduate on The Apprentice 2.
              Every episode is themed in a different
    manner, with The Donald voicing his definition
    of each theme. This central idea usually is the
    reason the next cast member is fired from the
    show. For example, a recent episode was
    themed, “You must think outside the box.” The



2                   The Ohio State Engineer                    Winter 2004
       Editor-in-Chief
        Dan Huynh
                                     TABLE                        OF            CONTENTS
    Advertising Manager
       Curt Mrowiec

        Design Team
         Dan Huynh                        features
         L. E. Smith

         Webmaster
         Adam Pervez
                                            4           Saving Heritage: Columbus Ohio
                                                                              Parag Agarwal
        Photography
         Olivia Miller

           Writers
                                            7           Superconductivity
                                                                                                   Dan Huynh
        Parag Agarwal

                                            12
         Dan Huynh
        Curt Mrowiec
                                                         “The world is changing” is a constant.
        Satya Thakkar                                                             Satya Thakkar
         L. E. Smith


        Staff Advisor                       13           The History of Lego
                                                                                                  Curt Mrowiec
         Ed McCaul


        Special Thanks
         Gina Langen
                                            14           Defining Paris Engineering
                                                                                                   L. E. Smith


                                          departments

Office: Rm 181 Hitchcock
        Hall 2070 Neil Ave.
                                            2           From The Editor:
                                                                                                   Dan Huynh
        Columbus, OH 43210

E-mail: OSE@osu.edu
Fax:    (614) 688-3805
Phone: (614) 292-7931
Web: ose.eng.ohio-state.edu

Advertising rates and media kits
available upon request.


The Ohio State Engineer is a mem-
ber of Engineering College Maga-
zines Associated. The Engineer is
printed in the autumn, winter, and         Front cover: A view of downtown Columbus, Ohio. Back
spring by the students of the Col-   cover: Eiffel Tower, Paris France. Photographys courtesey L. E.
lege of Engineering at The Ohio      Smith, Graduate MRCP Winter 2004
State University.

                                     Winter 2004                        The Ohio State Engineer                  3
                        SAVING THE HERITAGE:
                          COLUMBUS, OHIO By: Parag Agarwal
    “Therefore, when we build, let us think we build forever............let us think, as we
      lay stone on stone, that a time is to come when those stones will be held sacred
                          because our hands have touched them.”
                                        John Ruskin.
         Historic resources are vital elements     eyes, has been long known for its
    of our Nation's cultural gamut and they        fine buildings and historic neigh-
    contribute significantly to the society        borhoods. Columbus architectural
    and to individual’s identity. Let’s face it:   heritage includes the German Vil-
    the word ‘Historic Preservation’ is con-       lage, largest privately funded His-
    voluted and encompasses an array of            toric District on the National Reg-
    different subjects, but most people relate     ister of Historic Places, and the
    ‘historic’ with ‘age’ and for them ‘His-       State Capitol building built in
    toric Preservation’ deals with protection      1861. However, over the last few
    of ‘old’ or ‘ancient’ buildings. ‘Old’ or      decades the city has been sculpted
    ‘ancient’ are again the relative words,        by its own growth. Due to the dif-
    which may depict different time frames         ferent actions of public and private
    for different cultures. Romans, pioneers       sectors, historical properties have a
    of civilization will call St. Peter’s of       way of disappearing. They quietly
    Rome at Vatican City built in mid 16th         fall prey to demolition, or renova-
    century as historic, while in the United       tions, the most notable amongst
    States we even classify Pennsylvania           them was the razing of Union Sta-
    Station in New York built in 1910 as a         tion in 1976 to make way for tem-
    celebrated structure. When you cut             porary parking related to the Na-
    through all the slang and rhetoric, His-       tionwide Arena construction
    toric Preservation is simply saving any        project. To prevent the blunders of
    structure or neighborhood that is signifi-     historic magnitude, the preserva-
    cant to the nation and to the society.         tion movement started in the city in
         Many say that the concept of ‘pres-       1960 with the formation of the
    ervation’ is simply against the American       German Village Society to rejuve-
    psyche and traditions, who are consid-         nate the south end of Columbus
    ered to be the world’s principal consum-       now known as the German Village.
    ers. American’s have always favored            Although a more formal beginning
    ‘change’, ‘growth’ and ‘development’,          took place about three years later
    the words which are visualized to be           when the city got its first Historic
    contradictory to the fundamentals “pres-       District: German Village, in 1963,
    ervation’. However, the interest in His-       three decades after the formation of
    toric Preservation arose in the twentieth      first historic district of United
    century when our society grew mature           States in Charleston, South Caro-
    and the focus shifted from quantitative        lina.
    to qualitative aspects of development,              Since then, numerous organiza-
    which led to the interest in preserving        tions like Columbus Landmarks
    the quality built environment.                 Foundations, Ohio Historical Soci-
         Columbus, the state capital of Ohio       ety, Ohio Preservation Alliance
    and most importantly the home of Buck-         have been formed through commu-
                                                   nity initiatives to safeguard the

4                 The Ohio State Engineer          Winter 2004
city’s heritage.                                      bus Register does not guarantee any tax
     The historic character of Colum-                 incentives or state or city funding, the
bus neighborhoods is maintained by                    property owners have other benefits
five architectural review commissions                 like the historic designation reinforces
whose primary function is to review                   the architectural importance of the
any structural alterations or new de-                 building and provides protection to the
velopments that take place in their                   neighborhood from incompatible
jurisdictions. The four village archi-                changes.
tectural commissions (German Vil-                         The proposed establishment of

   The Vanishing Automobile
lage, Victorian Village, Italian Village              Historic Districts, covered by ordi-
and the Brewery Village) help in pre-                 nance, has often been met with opposi-
serving the character of the city’s four              tion with a variety of concerns. It is




              Housing character, adds to the historic fiber of the German Village


 and Other Urban Myths the concept of
historic neighborhoods. The fifth com-
               very by Alex Iams to address these misgiv-
                    important
mission: Historical Resource Commis-
               ings when promoting
sion (HRC) was created to protect the                 Historic Preservation. The following
character of the buildings and neigh-                 are some of the primary misconcep-
borhoods listed in the Columbus Reg-                  tions which the people have, related to
ister of Historic Properties, which is                preservation movement:
City’s official listing of buildings,                      Misconception: Preservation is
sites and districts of architectural and              only for high-style buildings associated
historical significance. There are cur-               with famous, dead, and rich people.
rently nineteen designated Historic                        Truth: As stated in the introduc-
Districts and forty two properties                    tory statements, preservation deals
individually listed in the Columbus                   with all built environments that are
Register of Historic Properties, with                 significant to the nation. Many of the
the first being registered in 1982. To                properties listed in the Columbus Reg-
be eligible for the listing in the Co-                ister were built by working class or
lumbus register, all individual proper-               middle class families such as many
ties must be typically over 40 years                  properties in Historic Districts of Ital-
old and their nominations are strictly                ian and Victorian Villages. The Regis-
done on the voluntary basis. Although                 ter has a broad spectrum of properties
listing of the properties in the Colum-

                             Winter 2004                         The Ohio State Engineer          5
    ranging from government subsidized          the City of Columbus as compared
    housing, schools, cathedrals, post          to 478% in German Village in the
    offices and the courthouses.                given time frame.
         Misconception: Although the                Aesthetics, environmental,
    society benefits from the Historic          educational, social, and psychologi-
    Districts, the residents are unsatisfied    cal reasons – all justify the concept
    due to the various limitations im-          of Historic Preservation. Few real-
    posed on them.                              ize that through Historic Preserva-
         Truth: As expected Historic            tion, communities can create new
    Districts may be opposed by private
    individuals who assert their rights
    with a cry “Why am I being told what
    I can and can't do with my own prop-
    erty”? This attitude runs deep in
    American consciousness. This is
    perhaps the most misunderstood
    concern as most architectural reviews
    allows for alterations provided they
    do not damage the historic character
    of streetscape. Moreover the resi-
    dents buy the properties in the His-
    toric Districts with full knowledge of
    the architectural review guidelines          Brick paved streets adds to the pedestrian friendly
    and hence are expected comply to                  character of the Historic neighborhoods
    with them.
         Misconception: An architectural        jobs as rehabilitation and the con-
    review leads to reduction in the prop-      servation projects are highly labor
    erty values                                 intensive. Due to different initia-
         Truth: On the contrary, proper-        tives taken by public and private
    ties in the Historic Districts are worth    sector, our society has realized that
    more, appreciate faster, and retain         Historic Preservation is about keep-
    more of their value than properties         ing the best of the old in relation
    located outside the Historic Districts.     with new development.
    In fact, Historic District status and its
    architectural review have made Ger-
    man Village the most desirable
    neighborhood in Columbus although
    it was once the best example of 20th
    century urban decline till 1950s. To
                                                                 JOIN
    analyze the real estate market activity
                                                  Ohio State
                                                           The




    in Columbus, the study was con-
    ducted by German Village Commis-


                                                ENGINEER
    sion in 1999. As per the study, audi-
    tors assessed value of properties in
    German Village and in Columbus for
    the years 1963 and 1999. The result
    depicts that the property values ap-
    preciated by approximately 100% in          http://ose.eng.ohio-state.edu


6                 The Ohio State Engineer       Winter 2004
    Superconductivity
    By: Dan Huynh

     Introduction                          mum velocity the electron can reach.
     Since its discovery in 1911, super-   The amount of electron scattering
conductivity has been greatly dis-         determines the material’s resistance.
cussed in the world of physics. Super-     As temperature increases, so does
conductivity baffled the great minds of    electron scattering, hence the increase
physics for years until 1957 when John     in resistance. The resistance creates
Bardeen, Leon Cooper, and Robert           heat, and sometimes, light. When this
Schrieffer won a Nobel Prize for their     process occurs, energy is loss in the
theory on superconductivity, known as      system.
the BCS theory. Since then, supercon-             On the other hand, superconduc-
ductors have been used for a variety of    tors have no scattering because super-
applications, especially in regards to     conducting electrons do not collide with
surface and interface science. Super-      anything. There is no loss in energy or
conductors have been used in many          current because the electrons travel
different ways including, most notably,    through the complex lattice of the su-
magnetic resonance imaging (MRI). In       perconductive material unhindered.
addition, superconductivity surface and    One would imagine that since the rise
interface science has been vastly re-      in temperature correlates to the rise in
searched in the past few decades, and      resistivity, all that would need to be
has led to innovative discoveries re-      done is to decrease the temperature of
garding the fabrication of superconduc-    the material. This idea is a simple
tive thin films, the use of superconduc-   thought involved in a much more com-
tor-insulator-superconductor junctions     plex theory.
(Josephson junctions), and even mag-              Theorized by Bardeen, Cooper,
netic field imaging of material surfaces   and Schrieffer, the BCS theory explains
through Scanning SQUID Microscopy.         superconductivity when temperature
                                           begins to decrease toward absolute
     Fundamentals of Superconductivity     zero. The unification of current flow is
       Ideally, superconductors are        due to atomic lattice vibrations. Pairs
materials that can conduct electricity     of electrons, called Cooper pairs, are
without a loss in energy. There is no      formed in superconductors in order to
loss in energy because the supercon-       maneuver around obstacles that may
ductive material has very minimal resis-   cause scattering. Two electrons would
tance, or ideally, zero resistance. In a   normally want to repel each other ac-
normal metal, valence electrons be-        cording to the laws of physics. How-
come delocalized in the conduction         ever, as an electron passes close to an
band and roam around the lattice. As       ion in the lattice, an attraction between
an electric field is applied, electron     the negative electron and positive ion
velocity increases, but the electrons      causes vibrations that are passed from
collide with one another and scatter.      ion to ion until it reaches another elec-
Because of this fact, there is a maxi-     tron. This electron then absorbs the



                          Winter 2004              The Ohio State Engineer             7
    vibration. Therefore, the first electron   superconductivity called the critical mag-
    emits a phonon and the second elec-        netic field (Hc).
    tron mentioned absorbs a photon.               Antoher important factor of supercon-
    The force exerted by the phonons           ductors is critical current density (Jc).
    dominates the electrons’ repulsion,        The critical current density is another
    and thus, a Cooper pair is formed.         boundary point between conductivity and
           However, it should be noted that    superconductivity. All three of the critical
    Cooper pairs break apart and reform        values (Tc, Hc, & Jc) work very close
    constantly and are by no means per-        together.
    manent. The colder the temperature
    is, the longer these pairs stay to-             Josephson Junctions
    gether. If a superconductor gains                  Another important aspect of super-
    heat, the lattice vibrations will break    conductive materials is their use at inter-
    these Cooper pairs and force the           faces. For example, Josephson junctions
    material to lose its superconductivity.    are used when interfacing two supercon-
    The temperature that defines the           ductors together with a thin barrier in
                                               between them.
                                                     Two different types of Josephson
                                               effects can take place—an AC and a DC
                                               version. The AC Josephson effect in-
                                               volves the characteristic frequency oscil-
                                               lation of a Josephson junction being
                                               proportional to the voltage across its
                                               junction. Because of this feature, Jo-
                                               sephson junctions are used as a stan-
                                               dard measure of voltage. In the AC Jo-
                                               sephson effect, a voltage is applied to the
                                               junction, but with no magnetic fields ap-
         Figure 1: Schematic of a SQUID23      plied.
                                                    The DC Josephson effect involves
    boundary for conductivity and super-       applying a current instead of a voltage to
    conductivity is called the critical tem-   the junction until the critical current is
    perature (Tc). The lower the tempera-      reached. The Cooper pairs tunneling
    ture is from Tc, the more supercon-        through the barrier from one supercon-
    ductive the material.                      ductor to the other have a similar wave
         In the world of superconductivity,    function to that of a free particle. Also, in
    the higher the critical temperature is,    order for the junction to work properly, all
    the better it is for researchers since     the Cooper pairs must be phase coher-
    they have a larger temperature win-        ent, meaning that they all have the same
    dow to keep that material supercon-        phase. Once the critical current is
    ductive. In addition, if a current is      reached, single electron tunneling domi-
    applied to the material, a magnetic        nates the Cooper pairs. By placing an
    field (H) is created around it. Since      insulating layer in between the supercon-
    superconductors do not have a loss of      ductors, Cooper pairs can travel through
    energy or current, this magnetic field     the insulating barrier without any resis-
    is even greater for these types of         tance. This insulating layer is usually
    materials. Similar to temperature,         around 10-20 angstroms thick, and has to
    there is a magnetic field that defines     be smaller than the coherence length.
    the boundary for conductivity and          The coherence length is the maximum

8                   The Ohio State Engineer      Winter 2004
length the junction can be before it loses   a current above the critical current,
its superconductive effect.                  SQUIDs become operational.
     An interesting application to Joseph-          SQUIDs have been used for a
son junctions is to position a wire adja-    variety of applications such as magne-
cent to the junction and apply a current     tometers, gradiometers, DC compara-
to it. The magnetic field created by the     tors, noise thermometry, biomagnetism,
wire will actually lower the critical cur-   and brain imaging. However, in regards
rent of the Josephson junction. By           to surface and interface science, SQUID
using these principles, one can use a        technology has opened the door for a
Josephson junction as a switching de-        new type of imaging of surfaces—scan-
vice that switches at ultrahigh speeds.      ning SQUID microscopy (SSM).
Actually, the switching speeds of Jo-             Scanning SQUID Microscopy
sephson junctions have been measured                Since SQUIDs are the most sensi-
at ten times faster than traditional semi-   tive to magnetic fields, applying SQUID
conductor switches. Because of this          technology to the imaging industry has
fact, researchers have been working to       fostered great understanding of mag-
use Josephson junctions in computers         netic fields at the surfaces of materials
to improve speeds since computer
speed relies directly on the time needed
to transmit signal pulses. Actually, IBM
tried to perfect this theory by attempting
to use Josephson junctions to build a
computer. However, they had difficulties
when some of the computer’s circuitry
housed stray magnetic fields that af-
fected the mechanics of the Josephson
junctions. This quandary
serendipitously led to the invention of
the scanning SQUID microscope that
has been used to image magnetic fields
at material surfaces.
     Superconducting Quantum Interfer-
                                              Figure 2: Visual Representation of a Typical Scanning
ence Devices (SQUIDs)                                          SQUID Microscope
       A SQUID is a highly sensitive
magnetic field detector. Being ultra
sensitive to magnetic flux, a SQUID can      and elements. The use of SQUIDs to
measure magnetic fields of around 2 pT,      image magnetic fields at surfaces of
and some have been recorded measur-          materials is called Scanning SQUID
ing fields of about 100 fT.                  Microscopy. As discussed earlier, SSM
     SQUIDs can even measure mag-            was produced to solve problems with
netic fields hundred of billions smaller     trapped magnetic fields in prototype
than the earth’s magnetic field. SQUIDs      Josephson junction-based computers.
are basically superconductive loops that     IBM Co-op student F. Patrick Rogers
have two “weak link” Josephson junc-         designed the first SSM under the super-
tions in them.                               vision of Stuart Bermon at the IBM Tho-
     These two localized areas of the        mas J. Watson Research Center. The
loop where the Josephson junctions are       SSM was built as a diagnostic tool for
positioned are where the critical cur-       determining where magnetic flux was
rents are abruptly reduced. By applying      trapped. The basic design was made

                          Winter 2004                  The Ohio State Engineer                        9
     from a pickup loop connecting to a         rial are imaged through a computer by
     point-contact RF SQUID, beveled            forming false color images. These
     gears, driving rods, and DC motors.        images are that of weak magnetic fields
     The sample was then scanned past the       of the sample.
     pickup loop several times, revealing              Many other benefits of SSM have
     individual flux vortices in the niobium    been seen since the beginning of this
     through line-scan images. The spatial      unique technology. One important
     resolution was at a weak 500 µm and a      benefit of SSM is that it provides a
     signal-to-noise ratio of around 5 how-     method to magnetically image without
     ever.                                      damaging the sample. Also, there is a
            Since the first prototype of SSM,   low required current to operate the
     the experimental setup has changed in      SSM, while being able to image the
     order to improve magnetic imaging that     sample from both front and back. Most
     can reach a spatial resolution of 4 µm     recently, SSM samples do not need
     and a better signal-to-noise ratio of      preparation and can be imaged at room
     1000. By hanging the entire SSM from       temperature in air as opposed to the
     the ceiling, vibrations are reduced        classical method at cryogenic tempera-
     significantly and no external noise        tures.
     affects the system. Moreover, the                 Although SSM has many benefits
     SQUIDs used in SSM are fabricated          and pros in the magnetic imaging in-
     from niobium with thin film, aluminum      dustry, there have been some prob-
     oxide Josephson junctions.                 lems. First and foremost, the spatial
            In more recent versions of SSM,     resolution is quite poor compared to
     the SQUID is actually held stationary      Scanning Electron Microscopy with
     due to its sensitivity to external mag-    Polarisation Analysis (SEMPA). SSM
     netic fields and field gradients. Be-      has a spatial resolution at best 1 µm,
     cause of this fact, the sample is moved    whereas SEMPA can reach 30-50 nm.
     in a scanning fashion using a piezo-       Similarly, Lorentz microscopes can also
     electric scanning instrument. Scanning     achieve greater spatial resolution. By
     is quite important to SSM success          creating a pick-up loop with the diam-
     because the motor speed of SSM             eter that is roughly the distance from
     actually limits the scan time. However     loop to sample, the best balance be-
     some believe the SQUID response time       tween spatial resolution and sensitivity
     is the limiting factor.                    can be achieved. Actually, at the
            Scanning SQUID Microscopy is        Stanford Nanofabrication Facility, engi-
     so sensitive to magnetic fields that       neers are researching to develop pick-
     almost everything on the material’s        up loops that have a diameter of half a
     surface appears to be magnetic—            micron to a micron. By doing so, they
     sensing magnetic moments at a few          hope to increase SSM sensitivity and
     hundred Bohr magnetons, currents in        spatial resolution. Unfortunately, thus
     nanoamperes, and fields smaller than a     far, they have not been able to make a
     hundred picoteslas. SSM is capable of      niobium and silicon dioxide SSM pick-
     being sensitive enough to work in the      up loop due to problems with alignment
     dc to 400 gigahertz frequency range        during etching.
     while also being able to image spatial          Equally important, in the past, SSM
     resolutions to 4 µm. Amazingly, SSM        needed a cryogenic atmosphere that
     can even detects hidden wiring and         was a definite drawback by providing a
     defect that are imbedded in the sur-       restriction on the environment. How-
     face. The magnetic fields of the mate-     ever, research at the University of

10                The Ohio State Engineer         Winter 2004
Maryland states that using SSM on a
                                                    Currently, SSM has even been
room temperature sample can be per-
                                             used in the study of corrosion on metal
formed with success. Research is still
                                             surfaces. This study includes the
being performed in regards to tempera-
                                             analysis of aircraft lap joints and pos-
ture and the effectiveness of SSM.
                                             sible hidden corrosion. The reason
     Although there are some issues and
                                             SSM is well suited for this task is that it
problems, mainly with spatial resolution
                                             can map currents within the sample
issues, many applications for SSM use
                                             without actually touching the surface.
can be seen. SSM can detect power-to-
                                             This way, the sample is not damaged
ground shorts, along with logic shorts.
                                             and accurate results can be obtained.
Also, design verification can be per-
formed and determine package and chip
                                                  Conclusion
leakage.
                                                    In conclusion, superconductive
        SSM has been used to image
                                             materials have made a great impact
unexpected vortices that may appear in
                                             with their applications in surface and
circuitry and thin films. This application
                                             interface science. Having minimal to
is the reason SSM was invented—to
                                             zero resistance, superconductive mate-
find vortices. Vortices encompass mag-
                                             rials, such as YBCO, havebeen used in
netic field lines that are trapped inside
                                             a wide variety of applications including
circuitry or a thin film due to external
                                             Josephson junctions and Scanning
magnetic fields. By using SSM, studies
                                             SQUID Microscopy.
have been made to deal with this prob-
                                                    Surface and interface science
lem. SSM can image where these vorti-
                                             researchers have greatly welcomed
ces are on the material, as well as imag-
                                             superconductive technology. From
ing the means to dea with these prob-
                                             superconductive interfaces, to the
lems. By setting up trapping sites—
                                             imaging of magnetic fields, supercon-
holes or moats—magnetic fields be-
                                             ductive surface and interface science
come trapped in these areas instead of
                                             has greatly helped many industries in
important circuitry. Imaging of these
                                             the world and should foster more ad-
holes and moats has been performed by
                                             vances in technology in years to come.
SSM to verify that this theory holds true.
SSM has proven that moats seem more
effective than holes in regards to trap-
ping these vortices.
     Likewise, the use of SSM to find
magnetic flux has been a useful applica-
tion to surface science. In order to
prove this fact, an experiment was set
up making four rings using a photolitho-
graphic process on bicrystal substrates.
A YBCO thin film was deposited via
laser onto the surface. The middle ring
had magnetic flux thread imbedded in it
while the others did not. The middle
ring image is much taller and provides
several colors, depending on the mag-
netism present in the ring, while the
other ones did not have magnetic flux
imbedded in them.                                   Figure 3: SSM Image of Fabricated Rings20


                          Winter 2004                The Ohio State Engineer                    11
      “The World is changing” is a
             constant.
                                      By: Satya Thakkar
          Every week we might find at least a       studied there were very unstable when
     small leap of advancement in our lives. Most exposed to oxygen and required a high-
     of these changes are the result of some        level of voltage to function. A team of
     engineer’s hard work, but whatever it may; it researchers at The Ohio State University has
     helps this world grow more beautiful and       discovered new LEPs that do not degrade in
     easy to handle in general.                     the presence of oxygen and can operate on
                                                    the amount of electricity produced by two
          One of the latest advances that might     AA batteries.
     change our lives in the coming decade or so
     is Light Emitting Polymers (LEP). LEP is a           LEPs belong to a special class of poly-
     technology based on the use of polymer as      mers called ‘conjugated’ polymers. These
     the semiconductor material in Light Emitting polymers posess delocalized pi-electrons
     Diodes. Polymers are chemical substances       along the backbone. In the sense of mobility
     that consist of large molecules that are,      of delocalized pi-electrons, LEPs show the
     themselves, made from many smaller and         potential of semiconductors. Unlike LCDs,
     simpler molecules: proteins and DNA are        LEPs have no restrictions on viewing angles
     examples of naturally occurring polymers.      and do not require backlight and color
                                                    filters. LEPs also can achieve an efficiency of
          Applications of LEP may be as diverse     5% which is comparable to conventional
     as changing the colors of your bedroom         LEDs at low voltages, but provide higher
     walls at a click, providing electronically     contrast and faster switching speed. In
     news on something called e-paper (different addition, the patterning process of LEPs is
     from the news on the websites), television     simple due to only one transparent sub-
     screens so thin they can be rolled up and      strate, coated with polymer layers, is re-
     stored in a living room corner, and video      quired. Therefore, thin, conformable display
     displays small enough for use on a cellular    screens become possible, using flexible
     phone and much more.                           plastic substrates.
                                                          Like ink a solution of a LEP can be
          In 1989, LEPs were first discovered by    used to easily "paint" an electrical light
     R. Friend and his colleagues at Cavendish      source onto an appropriate substrate. By
     Laboratory, Cambridge University (Holton, engineering the chemical structure of the
     1997). The team found yellow-green light       LEP all emission colors can be obtained.
     emitted from poly p-phenylene vinylene,        Because plastic materials are flexible and
     (PPV), when subjected to an electric field     robust even non-planar displays can be
     (Burroughnes et al., 1990). But the polymers manufactured.




12                  The Ohio State Engineer             Winter 2004
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  The History of the Lego
  By: Curt Mrowiec                                  due to Christiansen’s unwavering desire for
                                                    quality in Lego’s production. Today, this unwa-
     Over the past 70 years the “Automatic
                                                    vering quest for quality continues. The toler-
Binding Brick” has endured many changes and
                                                    ances for a Lego are within 1/1000 of a millime-
obstacles including two World Wars and one new
                                                    ter. This insures that every individual piece will
name, the Lego, to become one of the most
                                                    fit perfectly into any other piece. Christiansen
popular toys in the world. Presently, there are
                                                    has stood by his word that “Only the best is
52 Legos per person in the world. In fact, the
                                                    good enough.” The name Lego, in fact, means
Lego name has become so recognizable that it
                                                    “to play well” in Danish.
was added to the Oxford English Dictionary in
                                                             Today, Legos can be found in almost
1990. The Automatic Binding Brick was initially
                                                    every country throughout the world. Legos are
designed by Ole Kirk Christiansen, a master
                                                    no longer limited to the simple six stud bricks of
carpenter, in 1930 in small town in rural Den-
                                                    their beginnings. Now Legos come in hundreds
mark. Previously, Christiansen’s shop produced
                                                    of varying shapes. There are even motorized
step ladders, ironing boards, and wooden toys.
                                                    and robotic Legos. There are currently over
The master carpenter’s new creation – the
                                                    1,964 unique shaped bricks. Legos have be-
binding brick, was a flop in stores and
                                                    come so popular that there are amusement
Christiansen refocused his efforts on his previ-
                                                    parks devoted strictly to them. Lego Land in
ous ventures. It was not until 1947 when
                                                    California is home to many of the world’s largest
Christiansen purchased an injection molding
                                                    Lego displays. In fact, the largest Lego display
machine did modern Legos began to take the
                                                    in the world, the Technosaurus contains over
form with which people today are familiar.
                                                    one million individual Lego pieces, is located in
Christiansen was the first to use an injecting
                                                    Lego Land.
molding machine for the purpose of making
                                                             The Lego company is still privately
toys. A year later, a sailor, was introduced as
                                                    owned by the Christiansen family, and today
the first Lego man.
                                                    they employ thousands of people in Denmark,
        In 1950 a horrible fire swept through the
                                                    the United States, and the throughout the
Christiansen factory, destroying all the
                                                    world. This is a far cry from their original ten
company’s assets. It was at this time that Ole
                                                    employees in 1930. Today, the Lego Company
Kirk Christiansen decided to change the focus of
                                                    is worth in excess of two billion dollars.
his company. The name of his “Automatic
                                                    Throughout the world children and adults alike
Binding Brick” was changed to Lego. This also
                                                    spend more than 5 billion hours playing with
was to become the name of his company. In
                                                    Legos. The Lego has come a long way since its
the resulting years, the Lego began to explode
                                                    inception in the small 10 employee shop in
onto the world stage. In large part, this was
                                                    Billund, Denmark.


                                  Winter 2004                 The Ohio State Engineer                    13
     Defining Paris Engineering
           By: L. E. Smith
                                                                   the city. This protected the inhabitants and the king
           Imagine Paris. Now imagine Paris without the            from both invaders from the West and possible
     Eiffel Tower, without its boulevards - before its grand       usurping subjects to the East. This walled city
     existence as the City of Light. Examining the historical      became a model for other cities in search of protec-
     physical growth of the city gives us a good idea of why       tion from aggressors; an example can be seen in
     Paris is the way it is today with its beautiful apartment     Vienna, Austria. The outward growth stopped but
     buildings, large boulevards, Paris Canal, and of course       inside the city walls, the population continued to
     the Eiffel Tower. These engineering masterpieces have         grow, eventually to 250,000 by 1328. You can still
     set this city apart from others as well as provided           find parts of the original wall around the city and in
     necessary functions within it. A careful look reveals         the foundations of the Louvre, where this photograph
     the significance of each to the overall design of the city.   was taken.
           Paris began on the Île de la Cité in the 3rd                  Population increases necessitated the building
     century BC; it was founded by Celtic Gaules. Origi-           of the Paris canal, another engineering masterpiece.
     nating on the island in the middle of the Seine, the city     Aqueducts had been built under the city to draw
     grew first to the left bank of the river Seine then across    water from the Seine, but they were not enough.
     to the right bank. As the city became an important            Water was rationed to 2 pints per person, due to the
     trading center, it also suffered many invasions, all          intense shortage. King Louis XIV had vacated the
     which left their own distinguishing characteristics on        city and created Versailles as the new capital to
     the city. In 585 BC, the invaders were the Romans
     who conquered the city; the population at this time
     was 6,000. One can still find ancient Roman baths in
     parts of the left bank today. In 481 AD, the Franks
     attacked and took control.
           For 600 years the city continued to grow out-
     ward until King Philip Augustus in the 13th century
     built a castle and wall around the city for protection;
     the Louvre is part of the original walled city, which at
     one time defined Paris by enclosing it into 600 acres.
     The wall had a watch tower every 50 yards including
     the largest, the Great Tower which stood at 100 feet
     tall with a 150 foot circumference. It was a double
     barrier, one wall then an expanse that extended
     approximate 10 feet to another wall all the way around                            Paris Canal
                                                                   escape the problems contained within the city. After
                                                                   the Revolution, plague and lack of water forced a
                                                                   solution. Ordered by Napoleon and engineered by
                                                                   Pierre-Simon Girard, the Paris Canal stretches from
                                                                   60 miles outside the city to the Seine through the
                                                                   10th Arrondissement. The water is drawn by
                                                                   pumping stations still in use today, built and designed
                                                                   by Girard; the canal prove to be a difficult engineer-
                                                                   ing design as it is at height of 30 feet above the
                                                                   elevation of the river from which it is drawn. Foun-
                                                                   tains were also built at this time not only for beauty,
                                                                   but as a way to provide water to the people. Today
                                                                   the canal is still in service but has the added feature
                                                                   of attracting tourists to take a leisurely cruise down it.
                                                                         The next engineering feat was contributed by
                    Paris Wall inside the Louvre

14                      The Ohio State Engineer                     Winter 2004
                                                           only the one skyscraper due to the aqueducts and
                                                           excavation of limestone resulting in an unstable
                                                           underground physical geography of the city.
                                                                 Gustave Eiffel’s construction at the time, one
                                                           of the world’s largest tower, has become a land-
                                                           mark symbol of Paris. It was originally built for the
                                                           World’s Fair of 1889 and to celebrate the centen-
                                                           nial of the French Revolution as a temporary
                                                           display. Two engineers Emile Nouguier and
                                                           Maurice Koechlin, in Eiffel’s metalwork company
                                                           proposed the idea in 1884. After submitting and
                                                           receiving a patent for their design, they turned to an
                                                           architect, Stephen Sauvestre to make the project
                                                           more appealing to the eye. It was a tribute to the
                                                           industrial age, where metalwork and man’s
                                                           achievement could be displayed for all to see. As
             Haussmann’s grand boulevards                  time passed, it became an inspiration for artists and
Baron Georges-Eugene Haussmann, who began one of           writers who helped in portraying the tower as a
the largest urban renewal projects ever completed; it      symbol of the city. In 2000 for the New Year’s
changed and influenced the social as well as psychologi-   Eve celebration, the tower was festooned with
cal redevelopment of city landscape. After the French      lights and a large digital display. The lights continue
Revolution the city was in shambles, unemployment,         to this day lighting up the tower after dark for 10
and mass poverty affected most inhabitants. Narrow         minutes on the hour.
streets and aging sewer systems reflected a dismal               All world class cities have distinguishing
existence for most Parisians. In a massive effort to       landmarks that set them apart from other cities; go
employ the population and rebuild the image of Paris,      see for yourself why Paris is a world capital, not
Napoleon III appointed Haussmann prefect and               only for its fashion and art. It is a city of great
directed him to incorporate the Paris suburbs; this        history and architectural design, no one event
increased the population by 400,000 as well as dou-        shaped this city into its current embodiment, but all
bling the land attributed to the city. His urban design    together created its beauty and place in the world
plan was to open up the old center of the city by          as the remarkable City of Light.
improving transportation and circulation, bring green
space into the city and combine state interests with
private interests in development. Haussmann united his
wide boulevard design while maintaining some of the
smaller streets and erected large apartment buildings
with the ground floor commercial space and upstairs
residential housing units. This helped sustain the
density of the city while maintaining community and
neighborhood qualities of distinct areas, according to
Michael Carmona, author of Haussmannn: his life and
times, and the making of modern Paris. The dual
nature of the design opened the city, as well as pro-
vided access throughout. He kept in mind that another
revolution was possible and this design prevented
portions of the city from being sectioned off by revolu-
tionaries while continuing to nurture Paris neighbor-
hoods and communities. The city’s rooftops and wide
boulevards can be seen in this picture taken from atop                        Eiffel Tower
Montparnasse, the city’s only skyscraper. The city has
                                 Winter 2004                      The Ohio State Engineer                            15
16   The Ohio State Engineer   Winter 2004

				
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