Water buffaloes and cattle differ considerably with respect to the anatomy of the head. As a result, captive bolt stunners often fail to reliably produce adequate loss of consciousness in water ...buffaloes and, thus, do not fulfill animal welfare requirements. The goal of the present study was to assess and validate a new stunning device for water buffaloes meeting animal welfare and occupational safety requirements. The newly designed bullet casing gun uses .357Mag/10.2g hollow point bullets and has additional safety features. Its effectiveness and usability were assessed under practical conditions in an abattoir as based on widely accepted criteria. Stunning resulted in deep unconsciousness in 19 out of 20 water buffaloes. One 9-year old male did not immediately collapse. Except for very old bulls, the device presented herewith provides a means to stun water buffaloes of both sexes effectively and reliably while keeping occupational hazards to a minimum.
Educational Use of a Small-Scale Cherrypicker Maleki, Ehsan; Pridgen, Brice; Singhose, William ...
International journal of mechanical engineering education,
04/2012, Letnik:
40, Številka:
2
Journal Article
Cherrypickers are a useful class of machines that can lift people to great heights. Unfortunately, the operator bucket oscillates and the entire machine can tip over in catastrophic accidents. ...Understanding the dynamics and stability of these machines is crucial for efficient and safe operation. To this end, a small-scale cherrypicker was constructed for experimental dynamic analysis and educational use. The dynamic behavior of the cherrypicker, as well as the improved system response using vibration-control techniques are presented. The cherrypicker was used during fall 2010 as an experimental apparatus in an advanced graduate controls course taught simultaneously at the Georgia Institute of Technology and the Massachusetts Institute of Technology. Its educational use in this multi-institutional course is discussed.
Designing advanced control systems is a challenging task that requires the integration of numerous simulations and experiments into the design decision-making process. Unfortunately, controls courses ...are often focused on theory and do not provide students with knowledge, or practical experience, of how to actually implement controllers. Programmable Logic Controllers (PLC) are often used in industrial applications. PLCs continue to improve their computational abilities and are nowadays capable of running codes generated with MATLAB/Simulink. A two-week curriculum was added to a graduate controls course to teach students operational techniques and programming of PLCs. Students developed skills necessary to design a controller using logic operations, logic gates, PLC programming, and a Human Machine Interface (HMI). The curriculum required the programming of a PLC and HMI to control automated test equipment with electro-pneumatic components.
Cherrypickers are a useful class of machines that lift people to great heights. However, a major drawback of cherrypickers is that they oscillate when they move. Under-standing the dynamics and ...stability of these machines is crucial for efficient and safe operation. To this end, a small-scale cherrypicker was constructed for experimental dynamic analysis and educational use. Experimental results confirm the benefits of the vibration-control techniques developed for this machine. The cherrypicker was used during Fall 2010 as an experimental apparatus in an advanced graduate controls course taught simultaneously at the Georgia Institute of Technology and the Massachusetts Institute of Technology. Details of its educational use are discussed.
A 30-ton industrial bridge crane located at an aluminum sheet manufacturer has been equipped with a crane manipulation system enabling swing-free motion, disturbance rejection, and precise ...positioning. Previous investigations of anti-sway, positioning, and crane control have yielded important contributions in these areas. These advancements are combined into the unified crane manipulation system described here. An overview of this system is presented, along with experimental results, and a description of how human operators use the crane.
Human manipulation of suspended payloads using cranes can be difficult. Cable sway is easily induced into the lightly damped system, which inhibits efficient, safe, and accurate payload manipulation. ...This problem is compounded when the payload forms a double-pendulum configuration. To aid operators, a wireless touchscreen controller was integrated into the control system of a 10-ton industrial bridge crane. This touchscreen allows an operator to move freely around the workspace and drive the crane with a simple graphical user interface. The operational effects of the touchscreen was compared to that of a standard pendent interface through a series of human operator performance studies. An oscillation suppression algorithm was used in conjunction with each interface. The touchscreen provides greater operator mobility while producing comparable manipulation performance.
An advanced controls class taught at both the Georgia Institute of Technology and the Tokyo Institute of Technology focuses on command generation, remote manipulation, and human interaction with ...control systems. To aid in teaching these concepts, a portable tower crane was constructed. The tower crane can follow pre-programmed trajectories or be driven manually. It can also be operated from anywhere in the world with an internet connection. The crane can perform both feedback and command shaping anti-swing control while measuring trolley position and payload swing. The system enables students to perform a variety of useful and interesting laboratories and student projects. The students participated in and studied the effects of remote operator behavior, non-linear system dynamics, and advanced command generation techniques. The paper describes the tower crane and the results of this new educational endeavor.
Light affects many physiological processes in mammals such as entrainment of the circadian clock, regulation of mood, and relaxation of blood vessels. At the molecular level, a stimulus such as light ...initiates a cascade of kinases that phosphorylate CREB at various sites, including serine 133 (S133). This modification leads CREB to recruit the co-factor CRCT1 and the histone acetyltransferase CBP to stimulate the transcription of genes containing a CRE element in their promoters, such as Period 1 (Per1). However, the details of this pathway are poorly understood. Here we provide evidence that PER2 acts as a co-factor of CREB to facilitate the formation of a transactivation complex on the CRE element of the Per1 gene regulatory region in response to light or forskolin. Using in vitro and in vivo approaches, we show that PER2 modulates the interaction between CREB and its co-regulator CRTC1 to support complex formation only after a light or forskolin stimulus. Furthermore, the absence of PER2 abolished the interaction between the histone acetyltransferase CBP and CREB. This process was accompanied by a reduction of histone H3 acetylation and decreased recruitment of RNA Pol II to the Per1 gene. Collectively, our data show that PER2 supports the stimulus-dependent induction of the Per1 gene via modulation of the CREB/CRTC1/CBP complex.
In recent years, complex new bottom ash treatment processes for enhanced metal recovery have been implemented in Switzerland, producing residual bottom ash fractions with various qualities. This ...study focusses on three different treatment processes by characterizing all arising fractions in detail. Thereby the factors influencing the composition of these fractions are identified and their recycling potential in Switzerland is investigated. However, high legislative requirements on total contents of heavy metals represent a high barrier for bottom ash recycling in Switzerland. Therefore, the recycling potential is further evaluated based on the waste legislation applied in the Netherlands, where recycling of bottom ash has a long tradition. There, threshold values for bottom ash recycling are based on leachate concentrations and not on total contents as in Switzerland. However, Swiss Waste Legislation also knows threshold values based on leachate concentrations for certain waste materials. The leaching tests applied in these two countries, however, are different. The comparison of both leaching tests reveals that the setup and conditions, especially the considered pH range, significantly influence the leaching of heavy metals. With emphasis on problematic pollutants, the possibilities for new applications of these fractions are evaluated based on Swiss and Dutch legal threshold values. The comparison within the legal frameworks of these two countries allows recognizing opportunities and risks related to bottom ash recycling.
PDF
