An Analysis of Phase Transition in NK Landscapes

In this paper, we analyze the decision version of the NK landscape model from the perspective of threshold phenomena and phase transitions under two random distributions, the uniform probability model and the fixed ratio model. For the uniform probability model, we prove that the phase transition is easy in the sense that there is a polynomial algorithm that can solve a random instance of the problem with the probability asymptotic to 1 as the problem size tends to infinity. For the fixed ratio model, we establish several upper bounds for the solubility threshold, and prove that random instances with parameters above these upper bounds can be solved polynomially. This, together with our empirical study for random instances generated below and in the phase transition region, suggests that the phase transition of the fixed ratio model is also easy

Automatic Romaine Heart Harvester

The Romaine Robotics Senior Design Team developed a romaine lettuce heart trimming system in partnership with a Salinas farm to address a growing labor shortage in the agricultural industry that is resulting in crops rotting in the field before they could be harvested. An automated trimmer can alleviate the most time consuming step in the cut-trim-bag harvesting process, increasing the yields of robotic cutters or the speed of existing laborer teams. Leveraging the Partner Farm’s existing trimmer architecture, which consists of a laborer loading lettuce into sprungloaded grippers that are rotated through vision and cutting systems by an indexer, the team redesigned geometry to improve the loading, gripping, and ejection stages of the system. Physical testing, hand calculations, and FEA were performed to understand acceptable grip strengths and cup design, and several wooden mockups were built to explore a new actuating linkage design for the indexer. The team manufactured, assembled, and performed verification testing on a full-size metal motorized prototype that can be incorporated with the Partner Farm’s existing cutting and vision systems. The prototype met all of the established requirements, and the farm has implemented the redesign onto their trimmer. Future work would include designing and implementing vision and cutting systems for the team’s metal prototype

Utilization of ultrasound-guided peripheral intravenous access in the reduction of central venous catheter insertion

Intravenous (IV) catheter placement is the most frequently performed hospital procedure. IV catheters are essential for administering medications, fluids, radiographic contrast media, and collecting blood specimens. , However, IV catheter placement can be problematic in patients with veins that are not palpable or visible as this may delay the course of treatment. Most studies define difficult venous access as undergoing at least two IV attempts without success or use of other methods of IV placement. Alternative means of IV access include the use of an atypical vein (i.e., external jugular vein), ultrasound-guided peripheral intravenous catheter (USGPIV) placement, intraosseous (IO) device use, or central venous catheter (CVC) placement. Current literature suggests that chronic medical conditions, IV drug abuse, chemotherapy, sickle cell disease, obesity, and dialysis may be contributing factors to difficulty obtaining IV access.

Alien Registration- Culberson, Anna (Presque Isle, Aroostook County)

https://digitalmaine.com/alien_docs/33791/thumbnail.jp

Utilization of ultrasound-guided peripheral intravenous access in the reduction of central venous catheter insertion

Intravenous (IV) catheter placement is the most frequently performed hospital procedure. IV catheters are essential for administering medications, fluids, radiographic contrast media, and collecting blood specimens. , However, IV catheter placement can be problematic in patients with veins that are not palpable or visible as this may delay the course of treatment. Most studies define difficult venous access as undergoing at least two IV attempts without success or use of other methods of IV placement. Alternative means of IV access include the use of an atypical vein (i.e., external jugular vein), ultrasound-guided peripheral intravenous catheter (USGPIV) placement, intraosseous (IO) device use, or central venous catheter (CVC) placement. Current literature suggests that chronic medical conditions, IV drug abuse, chemotherapy, sickle cell disease, obesity, and dialysis may be contributing factors to difficulty obtaining IV access.

Air Pollution’s Effect on the Labor Force at the State Level

The health effects of air pollution are well established, ranging from increased rates of cancer to cardiovascular disease. Furthermore, a growing body of literature shows that air pollution has a tangible, negative impact on the labor force. However, in their efforts to avoid the endogeneity of air pollution and labor production, the current literature focuses on specific industries at a local level. The objective of this thesis is to expand this research to a state level by using naturally occurring weather events called air stagnations as a proxy for air pollution. These air stagnations correlate with increased levels of air pollution and because they are naturally occurring, they are exogenous to the labor force. This thesis finds that although there is a negative relationship between the air stagnations, which proxy for air pollution, and the growth of labor force productivity and output, the results are statistically insignificant at conventional levels

FEASIBILITY ANALYSIS OF STEAM VENTILATION IN SUPERCAVITATION DESIGN

The complete envelopment of a submerged object by a continuous cavity, or supercavity, results in significant reduction of the skin drag acting on the object, allowing for substantial increases in the maximum speeds of underwater devices. The formation of supercavities often requires supplemental ventilation, traditionally by non-condensable gasses, as natural supercavitation occurs at relative speeds between the object and liquid medium that are infeasible for the device to reach without supercavitation itself. The aim of this research is to investigate the feasibility of vaporous ventilation in supercavitation design with the hope of reducing non-condensable ventilation requirements which are inherently limited in their supply for submerged devices. Specifically, the partial or complete replacement of non-condensable gasses with steam for ventilated supercavitation was investigated to determine the effect on cavity development and ventilation requirements. While the use of vaporous ventilation gasses was unfound throughout the extensive literature review, a theoretical analysis which drew from various ventilation scenarios of steam insertion into liquid pools or flows suggested limited potential for the sole use of steam as a ventilation gas. In addition to a theoretical evaluation, cavitator systems were designed and tested to obtain both qualitative and quantitative results. Modest increases in the cavity volume and length were seen for very specific combinations of concurrent ventilation of steam and air relative to air only ventilation. The overall advantages appear extremely limited, however, as the ventilation requirements for steam addition are roughly an order of magnitude larger compared to the required increases of non-condensable ventilation for the production of similar results. Steam alone was shown to be entirely incapable of generating continuous cavitation structures for the range of steam flowrates tested, the upper limit being over three orders of magnitude larger than the critical air ventilation flowrate needed for successful creation of a continuous attached cavity. As such, the advantages of steam ventilation in supercavitation design appear very limited at best when compared to the relative ease of ventilated supercavity development by non-condensable gasses

Alien Registration- Culberson, Vera R. (Presque Isle, Aroostook County)

https://digitalmaine.com/alien_docs/33692/thumbnail.jp

Alien Registration- Culberson, Harold P. (Presque Isle, Aroostook County)

https://digitalmaine.com/alien_docs/33691/thumbnail.jp