On the interaction forces and responses of structural rings subjected to fragment impact Interim technical report, 1 Aug. 1969 - 31 Jul. 1970

FORTRAN 4 program for calculating dynamic Kirchhoff deformation of structural rings subjected to fragment impac

The Relationship Between Body Composition and Baseball Performance in Division II Baseball Players

Please view abstract in the attached PDF file

Integrated waveguides and deterministically positioned nitrogen vacancy centers in diamond created by femtosecond laser writing

Diamond's nitrogen vacancy (NV) center is an optically active defect with long spin coherence times, showing great potential for both efficient nanoscale magnetometry and quantum information processing schemes. Recently, both the formation of buried 3D optical waveguides and high quality single NVs in diamond were demonstrated using the versatile femtosecond laser-writing technique. However, until now, combining these technologies has been an outstanding challenge. In this work, we fabricate laser written photonic waveguides in quantum grade diamond which are aligned to within micron resolution to single laser-written NVs, enabling an integrated platform providing deterministically positioned waveguide-coupled NVs. This fabrication technology opens the way towards on-chip optical routing of single photons between NVs and optically integrated spin-based sensing

Fatigue evaluation in maintenance and assembly operations by digital human simulation

Virtual human techniques have been used a lot in industrial design in order to consider human factors and ergonomics as early as possible. The physical status (the physical capacity of virtual human) has been mostly treated as invariable in the current available human simulation tools, while indeed the physical capacity varies along time in an operation and the change of the physical capacity depends on the history of the work as well. Virtual Human Status is proposed in this paper in order to assess the difficulty of manual handling operations, especially from the physical perspective. The decrease of the physical capacity before and after an operation is used as an index to indicate the work difficulty. The reduction of physical strength is simulated in a theoretical approach on the basis of a fatigue model in which fatigue resistances of different muscle groups were regressed from 24 existing maximum endurance time (MET) models. A framework based on digital human modeling technique is established to realize the comparison of physical status. An assembly case in airplane assembly is simulated and analyzed under the framework. The endurance time and the decrease of the joint moment strengths are simulated. The experimental result in simulated operations under laboratory conditions confirms the feasibility of the theoretical approach

Physics

This departmental history was written on the occasion of the UND Centennial in 1983.https://commons.und.edu/departmental-histories/1050/thumbnail.jp

Ecology, Impacts, and Management of Invasive Rodents in the United States

Approximately 42% of all mammalian species in the world are rodents, amounting to about 2277 species (Wilson and Reeder 2005). Rodents have adapted to all lifestyles: terrestrial, aquatic, arboreal, and fossorial (underground). Most species are small, secretive, nocturnal, adaptable, and have keen senses of touch, taste, and smell. For most species of rodents, the incisors continually grow throughout their life span, requiring constant gnawing to keep the incisors sharp and at an appropriate length. This can result in extensive damage to seeds, fruits, field crops, structures, wires, and insulation. Rodents are known for their high reproductive potential; however, there is much variability between species as to the age at first reproduction, size of litters, and the number of litters per year. All these characteristics make many rodent species ideal invaders. Rodents have ecological, scientific, social, and economic values (Witmer et al. 1995; Dickman 1999). Rodents are important in seed and spore dispersal, pollination, seed predation, energy and nutrient cycling, the modification of plant succession and species composition, and as a food source for many predators. Additionally, some species provide food and fur for human uses. Hence, the indiscriminate removal of native rodents from ecosystems, including agroecosystems, is not the best management option in many cases (Villa-Cornejo et al. 1998; Aplin and Singleton 2003; Brakes and Smith 2005)

Telepresence and the Role of the Senses

The telepresence experience can be evoked in a number of ways. A well-known example is a player of videogames who reports about a telepresence experience, a subjective experience of being in one place or environment, even when physically situated in another place. In this paper we set the phenomenon of telepresence into a theoretical framework. As people react subjectively to stimuli from telepresence, empirical studies can give more evidence about the phenomenon. Thus, our contribution is to bridge the theoretical with the empirical. We discuss theories of perception with an emphasis on Heidegger, Merleau-Ponty and Gibson, the role of the senses and the Spinozian belief procedure. The aim is to contribute to our understanding of this phenomenon. A telepresence-study that included the affordance concept is used to empirically study how players report sense-reactions to virtual sightseeing in two cities. We investigate and explore the interplay of the philosophical and the empirical. The findings indicate that it is not only the visual sense that plays a role in this experience, but all senses

The Evolution of Bat Vestibular Systems in the Face of Potential Antagonistic Selection Pressures for Flight and Echolocation

PMCID: PMC3634842This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited