Category Archives: Civil Engineering

Construction, geodetics, HVAC, structural design, etc.

Emulating Metamaterials Using a Simple Printed Microstrip Design

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Summary:

Researchers at the Ohio State University’s ElectroScience Laboratory have been able to use simple (printed on uniform substrates) microwave circuit components to emulate the extraordinary propagation phenomena traditionally encountered in photonic crystals and metamaterials. These materials have been shown to exhibit unique and useful properties for microwave and optics applications such as delay lines, couplers, and antennas. One class of these structures demonstrated significant wave slowdown and amplitude increase within a small region, leading to miniaturization of antennas and other microwave circuit components. Another important property of metamaterials that has attracted significant research interest is the realization of a negative index of refraction. As the latter are difficult and expensive to manufacture, the proposed technology provides a practical approach to realize such unique properties. The researchers have already been able to realize these extraordinary properties using uniquely invented, cost effective, and easy to manufacture microstrip transmission lines arrangements.

Potential Applications:

  • Enables easy and inexpensive miniaturization of microwave and optical circuit components such as coupled lines, delay elements, phase shifters, printed antennas, antenna arrays, and solid state semiconductor optoelectronic devices
  • Enjoys the benefits derived from photonic crystals and metamaterials at a fraction of the cost
  • Enables a boost in gain while maintaining the same size dimensions

Advantages:

  • Compared to photonic crystals and metamaterials, this structure is much more cost effective and easier to manufacture, while exhibiting similar properties
  • Easy to retrofit with existing manufacturing processes and manufacture in volume since it is based on printed circuit technology

High-Performance, Economically-Viable Membranes for Carbon Dioxide (CO2) Separation

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Summary:

Economically viable removal of CO2 from sources such as coal plant flue gas and gasification mixtures requires affordable separation membranes that have high selectivity combined with high flux. State of the art membranes do not meet these requirements. Researchers at The Ohio State University have developed a new ultrathin inorganic membrane that exhibits high selectivity and a potentially high permeance for the separation of CO2 with respect to other gases. The membrane exhibits long-term stability, and operations over a wide range of temperatures.

Potential Applications:

  • Fuel Cells
  • Power Plants
  • CO2 recovery from fossil fuel combustion sources

Advantages:

  • Achieves both high CO2 selectivity and high flux
  • Can be easily manufactured

Carbon Monoxide (CO) Detector Operating at Room Temperature

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Summary:

Existing CO sensors are usually of either the electrochemical or optical variety. Inexpensive optical sensors, usually battery powered, are limited in their precision and lack displays to determine exact levels of CO concentration. Electrochemical devices offer higher precision and offer a display for CO concentration, but must operate at elevated temperatures and thus must be plugged in to a wall outlet. Researchers at The Ohio State University have developed an electrochemical CO sensor that operates and senses CO at room temperature, thus eliminating the need for a heating device. Therefore, energy demands are far lower when plugged in to a wall outlet, and a battery-powered electrochemical CO sensor can be achieved. This sensor can monitor CO in the ppm range and can be readily fabricated by screen printing techniques with deposition on polymer substrates. Sensors are miniaturizable.

Potential Applications:

  • Home, office, and industrial CO monitoring for occupant safety and fire detection
  • CO sensors can be incorporated into mobile devices, such as cell phones

Advantages:

  • Increased safety and sensor longevity as no heating device is needed
  • For the first time, battery-powered electrochemical CO sensors are possible
  • A portable, battery-powered CO sensor with a display becomes possible
  • Great reduction in energy consumption
  • Low-cost and easy to manufacture

Humidity-Interference Free, High-Temperature CO2 Sensor

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Summary:

Carbon dioxide sensors are becoming increasingly important in many applications including monitoring air quality, CO2 sequestration, measuring metabolic activity in animals, and controlling combustion. While commercial sensors for such applications exist, there is nothing currently on the market designed for reliability and effectiveness in high temperature and high humidity environments. Researchers at The Ohio State University have developed a reliable, high-performance carbon dioxide electrochemical sensor that works across a wide range of temperatures, is insensitive to humidity, and detects CO2 across a wide range of concentrations. These sensors can be manufactured by thin and thick film processing techniques, and can therefore be miniaturized resulting in a sensor with milliwatt power requirements for operation.

Potential Applications:

  • Combustion control
  • Monitoring of metabolic activity
  • CO2 monitoring in harsh environments
  • Power plant and industrial emissions monitoring
  • Automotive and aerospace emissions monitoring
  • CO2 sequestration applications

Advantages:

  • Humidity-interference free
  • Fast response and recovery
  • Long-term sensor stability in humid conditions over a wide range of temperature
  • Solid-state device

Chromium-Free Welding Consumables

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Summary:

Filler materials containing chromium are often used in the welding of stainless steel components in order to prevent corrosion.  The evaporation and oxidation of material from molten weld pools results in the generation of various compounds and metallic species in the fumes, including carcinogenic hexavalent chromium (Cr(VI)), which is an environmental and health hazard.  In fact, OSHA has recently set new standards for the maximum permissible exposure of Cr(VI) in the workplace.  Solutions such as alternative welding methods, ventilation systems, protective equipment, and medical monitoring can all help to reduce a worker’s exposure to Cr(VI), but these methods can be costly in terms of both direct and productivity costs.

To address this need, researchers at The Ohio State University have developed Chromium-free (and Manganese-free) welding consumables that are cost-effective and will help meet regulatory requirements without sacrificing the quality and corrosion-resistance of stainless steel welds, particularly type 304 steel.  As the consumable filler material is typically the major source of welding fumes, this solution is a very attractive and cost-effective way to meet regulatory requirements and help to ensure worker safety.

Potential Applications:

  • Welding consumables

    Advantages:

    • Cost effective
    • Excellent strength and corrosion resistance properties
    • Greatly reduces the amount of Cr(VI) found in welding fumes
    • Particularly suited for type 304 steel

      IP Status:

      Patent pending

      Neurodynamic Algorithm for Design Automation & Optimization(NeuroAutoOpt)

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      Summary:

      In the design of structures, systems have been developed to achieve optimization through the use of algorithms. However, algorithms of the prior art often fail in terms of convergence and stability, particularly for large nonlinear engineering systems. For instance, existing Computer-Aided Design (CAD) software systems have rudimentary optimization capabilities and can hardly handle large nonlinear systems. Another problem with prior art systems is that the data models employed do not take advantage of computing resources available today. Optimization of large structures with thousands of members subjected to actual constraints of commonly-used design codes requires an inordinate amount of computer processing and can be done only on multiprocessor supercomputers.

      Researchers at the Ohio State University have discovered a superior system for design optimization of highrise and superhighrise buildings with more than 20,000 members subjected to actual nonlinear constraints of commonly used design codes. Employing this invention can yield substantial weight savings in the design of large structures with millions of dollars of cost savings. This invention can also serve as a stepping stone in further improvement of CAD software.

      Potential Applications:

      Design of large structures.

      Advantages:

      • Substantial weight savings
      • Substantial cost savings

      Undetectable, Unjammable, and Interference-Free Ultra Wideband Radar System

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      Summary:

      Researchers at the Ohio State University have developed a virtually undetectable ultra wide band radar system that transmits pseudo random noise. On receive, the radar system cross-correlates a copy (possibly modified) of the original waveform with the receive signals. If a target reflects the signal (with modifications) then the radar will detect the reflection, the time delay, and Doppler. Thus the radar can tell the distance to a reflecting object and its relative speed. This is done using a waveform that will not interfere with other users of the spectrum. The noise waveform is extremely hard to detect. Researchers have further developed a system of storing the waveforms and performing the cross correlation at a particular time delay using a single memory device and no delay devices. This lends to the creation of a small, low cost, low power, stealthy radar that cannot be easily detected by conventional radar detection equipment and can be used for very short range applications. The radar can also be used to identify radar targets by using a pair of waveforms matched to the target radar impulse response. Thus the radar can also be used to detect only specific types of targets, as maybe required by the application.

      Potential Applications:

      • Speed radar gun manufacturers seeking an undetectable radar gun
      • Simple moving vehicle/person/object with identification potential (automotive lane change warning)
      • Highway management to evaluate strength of material, or helicopter air to air warning systems
      • Low cost ground penetration radar for pipes, land mine detection, or probing human bodies
      • Low cost building penetration radar (security systems at casinos and airports)
      • Cross section instrumentation radar with inverse synthetic aperture imaging radar ability
      • Moving Radar, synthetic aperture radar systems

      Advantages:

      • Robust with reference to interference or jamming – thus undetectable and hard to intercept
      • Unlikely to interfere with other noise radar systems or other radar systems in the same band
      • Low cost, small, light weight, and can be used for very short-range applications
      • Can be trained to be target specific (with the ability to specify multiple targets)
      • Would require no license to operate in civilian bands, and is fully coherent in amplitude and phase

      Ultrasonic Cleaning of Inorganic Cross-flow Filtration Membranes

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      Summary:

      A system has been developed which utilizes ultrasound to remove cake layer fouling from inorganic membranes. The system also prevents the sedimentation of patricles onto the membrane surface and reduces the concetration polarization near the membrane pore sizes. Inorganic membranes offer the potential of easier cleaning than polymeric membranes and the inorganic membranes are much more resistant to degradation by cavitation mechanisms generated by the ultrasound.

      Potential Applications:

      • Any area where inorganic membranes are used to remove particles are colloids, such as:
      • Removal of yeast cells from beer
      • Seperation of whey proteins in the dairy industry

      Advantages:

      • Removes cake layers without physically touching material
      • Reduces the concentration polarization