| NEWS & IDEAS |
November 1998
WORKPLACE AGGRESSION:
'Hey, sorry I'm late. (Not!)
CIVIL ENGINEERING:
Stirring Up Better Roads, Bridges
COMPUTER ENGINEERING
WWWPal--Website at a Glance
NUCLEAR ENGINEERING:
Radiation, Asbestos Detector
INTEGRATED ELECTRONICS:
Exacting Control of a Rough Process
WORKPLACE AGGRESSION:
'Hey, sorry I'm late. (Not!)
Disgruntled employees, who think they haven't been treated fairly, may express
their anger in covert ways that can hurt people and damage the company, says a
researcher at Rensselaer Polytechnic Institute. Workplace
aggression is more common than workplace violence, says Robert A. Baron, a professor
at Rensselaer's Lally School of Management and Technology, whose book, Human Aggression,
has been widely used for many years. The
forms of aggression people choose at work are likely to be disguised, says Baron.
"In other words, these people prefer to maximize the harm done to the victim and
minimize the danger to themselves," Baron says. Covert
forms of aggression include failing to transmit needed information, coming late
to meetings, wasting needed resources, or delay in response to phone calls or
memos, Baron says. Damning
with faint praise, spreading rumors, and mocking people behind their backs are
other forms of covert aggression, says Baron. "What's
particularly interesting is that we found workplace aggression to be more common
among Type A personalities," says Baron. "This squares with what we know about
Type A people. They tend to be impatient, highly critical, irritable, and less
forgiving." The
answer, says Baron, is for supervisors to make every effort to treat each employee
fairly. "Common courtesy goes a long way," Baron says. But he admits that some
people are never satisfied. The
findings, from a study of 452 employed people, will be published in the journal
Aggressive Behavior.
Contact: Robert A. Baron (518) 276-2864, baronr@rpi.edu
CIVIL ENGINEERING:
Stirring Up Better Roads, Bridges
With 44 percent of the bridges in the United States structurally deficient and
many highways in need of major repairs, there is a need for improved concrete
that can be used to build stronger, more durable structures, according to Joel
Plawsky. Plawsky
and Howard Littman, both members Rensselaer's Isermann Department of Chemical
Engineering believe concrete can be strengthened by improved mixing of the sand
(fine aggregate), rock (coarse aggregate), and cement it contains. Thorough
mixing is difficult because concrete consists of particles of widely different
sizes, explains Plawsky, who is project director. Mixing is even more complicated
for new "superconcretes," which include additional materials such as fly ash and
microsilica. The
difficulty in uniformly dispersing fine particle materials such as cement, flyash,
and microsilica in the sand and stone is the strength of the chemical and electrical
forces between the fine particles, Plawsky says. As an everyday example of the
problem, he suggests, try spreading flour uniformly on a surface. To
overcome poor mixing, industry now must add excess cement, which can weaken the
concrete and cause it to crack. Plawsky
and Littman propose fluidized bed technology to coat sand particles uniformly
with cement. The Transportation Infrastructure Research Consortium, a group sponsored
by the New York State Department of Transportation, has funded them to explore
this concept. In fluidized beds, now widely used for mixing in the petroleum industry,
for coating fine particles, and for combustion, air or another gas is forced through
a solid material, separating the particles so they float on the gas currents.
Plawsky
and Littman will use a fluidized bed, first to mix sand and cement and then for
a high-performance mixture including cement, sand, fly ash, and microsilica. Kenneth
Hover, professor of structural engineering at Cornell, will add water and rock
to their mixtures and then test the resulting concrete for strength, permeability,
and cracking. As
part of the program, Littman and Plawsky also will look at ways to obtain the
best concrete by varying proportions of the ingredients, and they will study the
surface chemistry of the aggregate to find ways to increase bonding between the
aggregate and the concrete mix.
Contacts: Howard Littman (518) 276-6039, littmh@rpi.edu; Joel Plawsky (518) 276-6049, plawsky@rpi.edu
COMPUTER SCIENCE
WWWPal--Website at a Glance
It will soon be possible to view your entire web site at a glance and see it spread
out like a map that shows every document, every page, every connecting road, and
every link to someone else's site. The
software, dubbed WWWPal, was created by computer science professor Mukkai Krishnamoorthy
and doctoral student John Punin. When
completed, the program will be offered free to users everywhere. The
mapping system quickly reveals areas that are poorly organized, unnamed, misnamed,
or in need of simplification. Broken links, which would take a user to an error
message, are indicated in red. And
it's interactive. A simple click on any point on the map can identify that point
or even open the document. The
value of the software for site organization and maintenance is obvious. But that's
just the beginning. It can also count all the documents in the site, and tell
you which documents are most popular to site visitors and which roads are barely
used at all. A
significant number of Rensselaer professors are now exploring research applications
of the mapping system, says Punin, who has been named to the Hall of Fame of the
W-3 Web Consortium for his contributions to the code library of the World Wide
Web. Two
years ago, the researchers developed a simple HTML editor, which was also given
away in the belief that university research should be for the benefit of all,
Krishnamoorthy said. In
November, the research will be presented at webNET '98 at Orlando, Fla.
Contact: Mukkai Krishnamoorthy (518) 276-6911, moorthy@cs.rpi.edu
NUCLEAR ENGINEERING:
Radiation, Asbestos Detector
Rensselaer researchers have developed non-destructive techniques to help the Department
of Energy (DOE) locate asbestos and radiation contamination in thousands of buildings
built in the 1940s and 1950s for the production of nuclear weapons. The
DOE has awarded George Xu, assistant professor of environmental and energy engineering,
a three-year contract for $599,687 to further explore the technology and to develop
a prototype portable system. Physics Professor Xi-Cheng Zhang is co-principal
investigator. At
present, it is necessary to take core samples and send them to a lab both to identify
asbestos and to determine the depth of any radiation contamination in walls made
of concrete or similar materials. Such core samples cost time and money and run
the risk of releasing radiocativity into the air. "We
can do it better, faster, safer, and cheaper," Lt. Col. Edward P. Naessens, a
doctoral student working with Xu, said at a recent meeting of the Health Physics
Society. Their presentation won a "best paper" award. About
two years ago, Xu realized it was theoretically possible to use gamma spectroscopy
to determine the depth profile of radiation contamination in situ without core
sampling. Undergraduates working with Xu on a senior design project developed
an algorithm that verified the idea. As
part of his doctoral work with Xu, Naessens is extending the simple model and
significantly improving its accuracy through extensive simulations and experiments.
But
to develop a comprehensive in-situ system to identify problems in DOE buildings,
Xu realized, it was also necessary to find a better way to identify asbestos,
a popular building material in the 1940s, which is now known to cause lung cancer
if inhaled. Xu
began collaborating with Zhang, using Zhang's real-time electo-optic terahertz
sensing. Instead of the portion of the spectrum used for X-rays, this system,
informally known as "T-rays," creates very sharp images using terahertz signals,
which are located between infrared and microwave radiation on the spectrum. Zhang
is exploring the medical use of this technology, as well as its potential for
such applications as locating plastic explosives. From
preliminary testing, Xu and Zhang found that different types of asbestos resulted
in unique signals that could be used as "fingerprints" for asbestos.
Contact: George Xu (518) 276-4014, xug2@rpi.edu
INTEGRATED ELECTRONICS:
Exacting Control of a Rough Process Detector
Chemical mechanical planarization (CMP), an old process being used in a new way,
is key to using copper wiring on computer chips, according to William N. Gill.
Unfortunately, not enough is known about a process that must be sufficiently exact
to remove layers of material that are measured in microns, he adds. Gill,
professor of chemical engineering and a member of the multi-university Center
for Advanced Interconnect Science and Technology at Rensselaer (CAIST), heads
a team that has built mathematical models to simulate CMP. The
importance of the work was recognized in San Diego in September, when the researchers
received the Best Paper award for interconnect modeling and simulation at TECHCON
'98, a conference sponsored by the industry-supported Semiconductor Research Corp.
Shyam Murarka, Parker Professor of Engineering and director of the CAIST, and
doctoral student Dipto Thakurta are co-authors. To
build smaller, more powerful computer chips, industry is moving from aluminum
to copper wiring. Processes such as etching that worked well with aluminum, however,
are not successful with copper. Companies
such as IBM have built chips with copper by using a "damascene" process in which
they put down a layer of insulating material and then etch trenches in it, Gill
explained. They next add a layer of copper and use CMP -- polishing with an abrasive
pad and a slurry containing chemicals and abrasive particles -- to bring it down
to the level of the insulating material, leaving copper in the trenches. Exacting
control is needed. Individual features on chips have shrunk from 1 micron 10 years
ago to .25 micron today and are expected to drop to .1 micron by the middle of
the next decade. (A human hair is 25 to 50 microns in diameter.) To
achieve this control, industry needs to understand and predict the effects of
changes in variables such as velocity, pressure, and distribution of the slurry.
Gill's models make that possible, and the predicted results have proven very accurate
when tested against experimental data.
Contact: William Gill (518) 276-2880, gillw@rpi.edu
