Physical Prop Research Articles

Merging the gap between physical and virtual realities: A pilot study on the role designed props play in creating a more immersive virtual experience

Virtual Reality (VR) technologies have gained momentum in various fields, including art and design, where it plays a significant role in modelling, prototyping, and testing. However, most VR headsets offer only visual and auditory inputs, leaving other senses unintrigued. This study has two objectives: First, to investigate whether a physical prop can create a more immersive experience. Second, to establish the relationship between the physical prop and memory retention of the virtual experience. Two VR rollercoaster conditions were created: one where participants simply sat on a chair, and another where they were secured in with a harness. Various qualitative and quantitative data collection methods were used, including physiological, observational, and self-reporting techniques. Biosensors were used to measure heart rate, breathing rate, skin conductance and brain activity, in addition to a survey. Early results confirm a positive correlation, with varying degrees, between the use of props in immersion and memory retention.

The main directions of scientific research in the field of introducing promising optical technologies in the infrastructure of transport systems.

Projects for the development of the transport system of the Russian Federation involve the introduction of advanced optical technologies in the infrastructure of high-speed modern transport systems in the context of the implementation of un- manned maintenance technologies. The article presents the following areas of research carried out by the authors: — organization of high-speed super-long single-span trunk communication lines without intermediate allocation of digital channels and paths laid in areas with limited access by the maintenance personnel in areas with no infrastructure (underwater obstacles, mountainous terrain, desert and swampy areas). The authors of the article highlighted the main factors influencing the design features of high-speed ultra-long single-span communication lines; — application of photonic switching (PS) technology in high-speed backbone communication networks to ensure operational logical reconfiguration of channel structures and digital paths. Within the framework of this direction of research, the authors have proposed methods for calculating the probabilities of the occurrence of internal blockages in various structures of PS based on the use of the method of mathematical induction in order to synthesize PS structures of a given capacity; — development of effective technologies for remote monitoring of the health of transport infrastructure facilities using passive optical transmission lines. Within the framework of this line of research, the authors analyze the features of the physical prop- erties of optical fibers used as a distributed sensor on the basis of which an integrated system can be built that can measure various physical parameters, such as vibration, deformation, temperature and other parameters.

ManipNet

Natural hand manipulations exhibit complex finger maneuvers adaptive to object shapes and the tasks at hand. Learning dexterous manipulation from data in a brute force way would require a prohibitive amount of examples to effectively cover the combinatorial space of 3D shapes and activities. In this paper, we propose a hand-object spatial representation that can achieve generalization from limited data. Our representation combines the global object shape as voxel occupancies with local geometric details as samples of closest distances. This representation is used by a neural network to regress finger motions from input trajectories of wrists and objects. Specifically, we provide the network with the current finger pose, past and future trajectories, and the spatial representations extracted from these trajectories. The network then predicts a new finger pose for the next frame as an autoregressive model. With a carefully chosen hand-centric coordinate system, we can handle single-handed and two-handed motions in a unified framework. Learning from a small number of primitive shapes and kitchenware objects, the network is able to synthesize a variety of finger gaits for grasping, in-hand manipulation, and bimanual object handling on a rich set of novel shapes and functional tasks. We also demonstrate a live demo of manipulating virtual objects in real-time using a simple physical prop. Our system is useful for offline animation or real-time applications forgiving to a small delay.

Using the Visuo-Haptic Illusion to Perceive and Manipulate Different Virtual Objects in Augmented Reality

The prop-based 3D virtual object manipulation method is widely used for interaction in Augmented Reality (AR) due to its convenience and flexibility. However, when the represented virtual object is different from the physical prop, the look and feel of the object are not well aligned. To address this problem, we present a dynamic finger remapping approach to creating a visuo-haptic illusion that dynamically adjusts the presented virtual hand posture to fit different sizes and shapes of virtual objects in AR. The finger movement toward a physical prop is synchronously remapped to the movement of the virtual fingers towards the corresponding virtual object. We developed a system that enables users to perceive consistent visual and tactile feedback while grasping and releasing various virtual objects represented by a physical prop. We conducted a user study to explore the effect of this visuo-haptic illusion on the perceived size of virtual objects, setting the sizes of the rendered virtual object and the physical prop as independent variables. We found that the perceived size of a virtual object varied with its rendered size in an almost linear fashion, while the physical prop size did not significantly affect the perception. We also conducted a second study to compare our system with a current prop-based method on virtual object manipulation. The results indicated that the remapped hands could effectively improve the realism and naturalness of the experience.

Calibration and Evaluation for Visuo-haptic Collocation in Haptic Augmented Virtuality Systems

Haptic augmented virtuality systems can provide users with a highly immersive haptic experience by visuo-haptic collocation of physical objects with their corresponding virtual objects. The collocation can be accomplished by an encounter-type haptic display system where a robotic device provides a physical prop that represents a whole or partial virtual object in real-time and in the space occupied by the virtual object in the virtual environment. For efficient and accurate visuo-haptic collocation, this paper proposes a novel yet simple, efficient and accurate calibration method. The method employs a high-accuracy position device such as an industrial robot that can place physical objects quickly and accurately. The transformation between the reference frames of the real (robot) and virtual worlds is obtained by the simple motion of the robot’s end-effector equipped with a real object that is in turn tracked by a VR tracker system such as the HTC VIVE tracker. An evaluation of the proposed method indicates that it is possible to achieve acceptable accuracy with a few data points as compared to existing calibration methods that require a large number of data points.

Among Actions, Objects, and Ideas: The Telescope in Thomas Tomkis’s Albumazar

An engine to catch starres: Thomas Tomkis and Natural Philosophy (1) Ibumazar is a play filled with things, from mundane household goods to lists of ancient and contemporary alchemists and magi to the eponymous astrologer's collection of astrolabes, horoscopes, and almanacs. It is also the first play in English to feature a scene with a telescope onstage. (2) However, whether many of the things in Thomas Tomkis's (c. 1580-after 1615) farce physically appeared onstage for its March 9, 1614 premiere at Cambridge's Trinity Hall is uncertain. The questionable material status of Tomkis's stage properties becomes significant when Albumazar is examined in a context of the history of as well as the history of theatre. The original college production demonstrates the playwright's cultural awareness of the emergent disciplinary distinction of astronomy through the incorporation of its star technology: the telescope. (3) King James I (1566-1625)--witch-hunter, author of Daemonology (1597), and royal guest at Albumazar's premiere--likely held a derogatory opinion of the telescope because of its potential use as a tool in the occult craft of astrology. The space between the textual narrative and the telescope scene as it might have been embodied by actors in 1614 reveals the delicate balance that Tomkis achieved by referring to truthful elements of astronomy while poking fun at astrology. The manner in which the telescope was performed--as a physical prop or mimed as part of a dumb show--indicates the range of Tomkis's engagement with the tools and concepts of the science in the only performance of the play recorded during his lifetime. The science advanced the idea of experimentation and experience as a means of exploring the natural world. (4) This method prioritized embodied encounters and observations of natural phenomena (including things astronomical) over contemplation of Aristotelian causes thereof. The science began to emerge with Galileo Galilei's (1564-1642) empirical observations and was developed in England most famously by Sir Francis Bacon (1561-1626), who preceded Tomkis at Trinity College, from 1573-1575. (5) Staged representations of the telescope throughout the seventeenth century evidence a gradual shift in popular opinions about the science and those who adhered to its philosophy. Tomkis's use of the telescope in the play references a host of overlapping traditions of science, magic, education, and authority that were at odds with each other at the time of the play's premiere. In 1614, astrology and astronomy were not entirely distinct disciplines and neither was completely condoned, or forbidden, by religious and scholarly authorities. Astrology had historically been taught at European universities, but the church and university considered certain aspects of astrology less offensive than others. (6) Act 1 of Albumazar features a telescope (referred to throughout the play as aperspicill) and an otacousticon (a hearing aid). (7) These devices situate the play at a pivotal moment in the history of as reports of new discoveries made through the use of Galilean tubes spread across Europe. (8) The traditional narrative of the telescope's invention goes that in 1608, Dutch spectacle-maker Hans Lipperhey (1570-1619) was granted a patent for his telescope design from the States General in Hague, Holland, and so the chapter of the telescope was added to a global history of astronomical technologies. (9) Galileo Galilei (1564-1642) announced his application of the telescope to the practice of astronomy in 1610 with the publication of Sidereus Nuncius (The Starry Messenger). (10) What followed was a European battle of philosophies over the veracity of the celestial objects made visible through the telescope's lenses waged throughout the seventeenth century. (11) At the time, knowledge gained through the use of telescopes was not universally accepted because discoveries of new stars and planets, as well as the ability to trace their movements with greater accuracy, challenged a Ptolemaic (geocentric) model of the universe that was still popular within the academy and the church. …

Framing a topic: Mobile video tasks in museum learning

Abstract This study explores the conceptual framing work of a group of upper secondary students as they first collaborate to understand a particular science museum exhibit, and then relate aspects of the exhibit to a larger scientific principle. The task involved producing a video of the groups' explanation to a problem using a mobile device. Applying methods from interaction analysis we examine how the group accomplishes and performs conceptual understanding. The analysis shows the indexical affordances of video as medium in the setting, allowing students to use the exhibit as a visual and physical prop in the film to explain scientific concepts. Moreover, we found that the students' conceptual work was conducted in advance of making the video, and that making the video entailed collaboratively actualizing understandings previously accomplished in the group. Based on our findings, we propose that video tasks may be a productive way to ‘frame topics’ and orient students to disciplinary aspects of museum exhibits.

Hydrodynamics in mangrove prop roots and their physical properties

The circulation of water in riverine mangrove swamps is expected to be influenced by mangrove roots, which in turn affect the transport of nutrients, pollutants and sediments in these systems. Geometric properties of mangrove (Rhizophora sp.) prop roots in the field were studied through the use of photogrammetric methods and samples of such roots were harvested to determine their material properties in the laboratory. The field studies were carried out in the mangrove areas along some of the coastlines of Singapore where the Rhizophora genus are located. We found that the prop roots under tidal hydrodynamic loadings in a mangrove environment can be regarded as fairly rigid on account of a large Young's modulus of about 15 GPa. Physical prop root models were fabricated from downscaling based on field observations with porosity values ranging from 0.96 to 0.98. Flume experiments were performed and measurements of mean flow velocities, Reynolds stress and turbulent kinetic energy (TKE) were made. Our results indicate that the prop roots provide blockage effect on the flow and cause complex secondary flow. The turbulence energy can be generated by both wake and shear, with shear-generated turbulence being dominant in the upper open area between prop roots. A force balance analysis was performed in the nearly uniform flow region to investigate the flow resistance caused by the prop root models. The Chézy roughness coefficient C was found to be 10 and the drag coefficient CD was found to be 1.2 in the fully developed flow, which agrees with reported field studies in mangrove swamps.

A much needed compilation of studies of a Neotropical elevation gradient

book reviews ISSN 1948-6596 A much needed compilation of studies of a Neotropical elevation gradient Ecological Gradient Analyses in a Tropical Landscape: Ecological Bulletins 54. Grizelle Gonzalez, Michael R. Willig & Robert B. Waide (editors), 2013, Wiley-Blackwell. 252 pp. £37.50 (Hardback) ISBN: 9781118659328; http://eu.wiley.com/ Since Humboldt’s studies of mountain regions (Humboldt and Bonpland 1807), altitudinal gra- dients have served as a foundation for many ecological processes documenting biodiversity and species distributions. The Luquillo moun- tains in Puerto Rico are perhaps one of the most studied tropical montane forests, where tree distributions across the gradients have been well documented (Weaver and Murphy 1990). Studies in these mountains have gener- ated foundational knowledge about tropical ecology, such as the transition and classifica- tion of ecosystems or “life zone systems” in a landscape (Holdridge 1947), the importance of cloud cover on tropical montane forests (Te Linde et al. 2001), and the impacts of hurri- canes on forest structure (Scatena and Larsen When studying elevational gradients we generally have two choices. Start description and observations of lesser-known mountains, the species occurring in them, and the hydrol- ogy and geology of sites across the gradients; or, build on previous knowledge of the few mountain ranges that are well studied and de- sign experiments based on findings that date from the 1940s. There are advantages in each approach but there is unique value in studying a well known mountain range: previous knowl- edge enables the range to be used as a natural experiment in which species’ distributions and microclimatic and habitat transitions are known. Thanks to researchers including Leslie Holdridge, Fred Scatena, Ariel Lugo, Grizelle Gonzalez, Tamara Heartsil, Michael Willig, Robert Waide and others who devoted their lives to studying many climatological, ecologi- cal and geological aspects across the Luquillo mountains, we can further develop theories about elevation gradients and ask more com- plex questions about these processes. This book is a beautiful hard cover edition including a well-balanced compilation of 15 stud- ies describing the Luquillo mountains. The book is organized in four sections, preceded by an intro- duction of the current knowledge of the area and ending with an insightful conclusion. The compila- tion serves as a testament to the breadth of ques- tions one can pose in a mountain range that is well studied. It is a must-read for researchers planning to work in the Luquillo mountains, or any tropical mountains, since it will bring them up to speed with what has been studied and will pro- vide many insights to what still needs to be under- stood about tropical mountain ranges. Since the Luquillo mountains have been a center of attention for ecologists since 1947, cur- rent studies included in this book have been able to start looking at the diversity gradients of organ- isms that typically are neglected, like snails (Willig et al., p. 117), those dwelling in under-explored microhabitats such as soil, and epiphytes (Richardson and Richardson, p. 101). This book also describes how elevation affects less known aspects of ecology such as nutrient gradients and soil carbon (Medina et al., p. 157). The book in- cludes a study on changes in ecological function- ing across elevation which reveals that the gradi- ent in biogeochemistry (i.e., the REDOX gradient) does not have a linear relationship with elevation, forest type, or net primary productivity (NPP). In- stead, it is shown to be tied to the physical prop- erties of the soil, such as its bulk density (Whendee et al., p. 195). An important read for biogeographers and macroecologists is the study by Harris and collabo- rators (p. 233) who test the maximum power hy- pothesis. They clarify the balance between photo- synthesis and respiration to define the elevation at which the net power flow of the forest is maxi- mized. This elevation band corresponds to where vegetation complexity is at its highest and there frontiers of biogeography 6.3, 2014 — © 2014 the authors; journal compilation © 2014 The International Biogeography Society

The Comparison between the Quality of Lime Juices Produced by Different Preservation Techniques

Abstract Lime is an agricultural product that is exceptionally expensive during some periods of a year. In this research, juice was squeezed out from the fresh lime prior to exposing to four different processing schemes. They comprised with (1) pasteurization at 85 °C for 30 s, (2) pasteurization at 95 °C for 30 s, (3) UHT sterilization at 136 °C for 4 s and (4) vacuum evaporation at temperature range of 68-72 °C and vacuum pressure of 97325.35 Pa before pasteurization at 72 °C for 15 s. The main objective was to study the effects of processing methods on the physical prop erties of products so that the proper techniques for preserving lime juice would be identified. The specimens were kept at room temperature and measured their physical attributes every week for 7 weeks; as a result, it appeared that the reconstituted lime juice prepared from the sample manufactured by the fourth processing scheme had the most similar physical characteristics to the freshly squeezed lime juice. Furthermore, the panelists preferred this juice specimen to those produced from the other three methods that applied higher processing temperatures.

Quasicrystals

Quasicrystals are material with perfect long-range order, but with no three-dimensional translation periodicity. They are typically binary and ternary metallic alloys. Quasicrystals have characteristic physical properties. Some resemble those of periodic crystals while others have similar properties to amorphous alloys. Many of their mechanical physical prop- erties are quite unusual by the standards of common metals. The peculiar physical properties of quasicrystals certainly give rise to the hope that they may become of some practical importance in the future. Some of these properties are surface related. This provides the main motivation for surface scientists to study this material. In this paper; quasicrystals, types of them, physical properties, surface science and potential applications of them have been discussed.

ChemInform Abstract: Electronic Structure of Higher Acenes and Polyacene — The Perspective Developed by Theoretical Analyses

AbstractReview: 57 refs.

The effective stiffness of a nanoporous rod

279 Many nanomaterials have abnormal physical prop� erties, which differ considerably from the properties of bulk materials. One of the explanations for these dif� ferences consists in the presence of surface effects, the role of which can be extremely large for nanodimen� sional structures in comparison with those in classical mechanics [1]. The purpose of this work is analysis of the influence of surface effects on the elastic characteristics of nan� oporous materials. Two models are considered. The first one is based on taking into account the surface stresses [1–4]. The surface stresses τ are the generali� zation of the surface tension known in the theory of capillarity for the case of solids. As is shown in [1, 5], taking into account surface stresses results in increas� ing stiffness of nanoporous materials. This phenome� non is similar to increasing flexural stiffness of nano� plates in comparison with the plates of macroscopic sizes [6, 7]. The second model uses the approach of the theory of composite materials [8–10]. In this approach, the surface effects are taken into account due to the surface layer of finite thickness with elastic moduli differing from those of the basic material (the matrix). Here the increase or decrease in the rod stiff� ness depends on the relation between the elastic mod� uli of the surface layer and the matrix. The effective stiffness can both decrease and increase with decreas� ing pore radius. On the basis of these two approaches, we proposed a complex model combining both the presence of surface stresses and the surface layer with the properties that differ from those of the matrix. PROBLEM FORMULATION We consider the problem on the tension–compres� sion of a linear elastic rectilinear rod. Let the rod have a circular cross section of radius R. We consider that n cylindrical pores with identical radii r (Fig. 1) are located in parallel to the rod axis. We designate the area occupied with pores in the rod cross section as S = πnr 2 . We assume also that the rod cross section is symmetric so that it is not subjected to bending under tension. A regularly distributed load, which is stati� cally equivalent to forces P, acts on the rod end faces. We designate the Young’s modulus of the rod mate� rial as E. For a large number (n � 1) of pores, the rod can be considered as a homogeneous cylinder made of transversally isotropic material. We designate the cor� responding effective longitudinal Young’s modulus

Using relief texture for interactive and tangible virtual environments

This paper first introduces a way to improve interactivity with high polygon count virtual objects through the “mixed” use of image-based representation within one object. That is, both 3D polygonal and image-based representations are maintained for an object, and switched for rendering depending on the functional requirement of the object. Furthermore, in order to reduce the popping effect and provide smooth and gradual transition during the object representation switch, the object is subdivided with the subdivided parts possibly represented differently, i.e., using 3D models or images. As for the image-based representation, the relief texture (RT) method is used. In particular, through the use of the mixed representation, a new way called TangibleScreen is proposed to provide object tangibility by associating the image-based representation with a physical prop (projecting the RTs) in a selective and flexible way. Overall, the proposed method provides a way to maintain an interactive frame rate with selective perceptual details in a large-scale virtual environment, while allowing the user to interact with virtual objects in a tangible way.

Paleomagnetic reorientation of San Andreas Fault Observatory at Depth (SAFOD) core

We present a protocol for using paleomagnetic analysis to determine the absolute orientation of core recovered from the SAFOD borehole. Our approach is based on determining the direction of the primary remanent magnetization of a spot core recovered from the Great Valley Sequence during SAFOD Phase 2 and comparing its direction to the expected reference field direction for the Late Cretaceous in North America. Both thermal and alternating field demagnetization provide equally resolved magnetization, possibly residing in magnetite, that allow reorientation. Because compositionally similar siltstones and fine‐grained sandstones were encountered in the San Andreas Fault Zone during Stage 2 rotary drilling, we expect that paleomagnetic reorientation will yield reliable core orientations for continuous core acquired from directly within and adjacent to the San Andreas Fault during SAFOD Phase 3, which will be key to interpretation of spatial properties of these rocks.

Theoretical investigations of thermodynamic properties of partially deuterated K(H_{1-x}D_{x})_{2}PO_{4} ferroelectrics

The research of thermodynamic properties of partially deuterated K(H1 xDx)2PO4 crystals was performed within the framework of proton ordering model with tunnelling within the four-particle cluster approximation for short-range interaction and within the molecular field approximation for long-range interaction. The KD2PO4's model parameters were derived for the case of acceptable description of the experimental data for crystal ther- modynamic characteristics. Based on the introduced procedure of deriving parameters for K(H1 xDx)2PO4 crystals, the thermodynamic and dielectric properties of these crystals were calculated and the results were compared with the experimental ones. The problem of applying the mean crystal approximation to the analysis of physical characteristics of K(H1 xDx)2PO4 crystals was discussed. The investigations of partially deuterated ferroelectric crystals of the K(H1 xDx)2PO4 type make it possible to readily explain the thermodynamic and dynamic properties, peculiarities of the phase transitions, and the isotopic effect in the mixed ferroelectric crystals of the order-disorder type. A relatively simple structure of the KH2PO4 family of ferroelectrics and the peculiarities of their structure, related to the hydrogen bond system, allows us to use the methods and approxi- mations that provide high accuracy of calculation results. Close interplay between the theory and experiment is an essential point in the development of the physics of these crystals which makes it possible to work out adequate theoretical models and ultimately understand their physical prop- erties. Theoretic studies of the K(H1 xDx)2PO4 crystals ware carried out in the works (1-12). All studies of the mixed K(H1 xDx)2PO4 ferroelectrics were carried out within one of the modifications of the proton ordering model or within the proton-phonon model. The first model was proposed by Slater (13) and was developed and expanded in the works by Blinc (14,15), De Gennes (16), Vaks (17,18) and other researchers. Another model was proposed by Koboyashi (19) and then it was developed in the work (10). The first attempt to study the K(H1 xDx)2PO4 crystals was made by Tokunaga and Matsub- ara (1). The proton ordering model was exploited for the description of K(H1 xDx)2PO4 which was performed within the cluster approximation. In this work the assumption of the equality of all the interaction parameters for the KDP and DKDP crystals was made. The differences in the ferroelectric properties of these crystals were related to the tunnelling effects taking place in KDP: 6 0. Besides, it was assumed that the Tc(x) dependency can be obtained from the expression Tc() derived for pure KDP by replacing ! x·. However, the author failed to gain agreement between the theory and experiment for the Tc(x) dependency. Several other model theories related to the study of the dependencies of ferroelectric phase transition temperature and the Curie-Weiss constant on the deuteration level of K(H1 xDx)2PO4

Applications of Extraction Chromatography in the Development of Radionuclide Generator Systems for Nuclear Medicine

Numerous methods have been described for the separation and purification of radionuclides for application in diagnostic and therapeutic nuclear medicine, among them ion exchange, solvent extraction, and various forms of chromatography. Although extraction chromatography has previously been shown to provide a means of performing a number of separations of potential use in radionuclide generator systems, the application of the technique to generator development has thus far been limited. Recent work directed at improved methods for the determination of radionuclides in biological and environmental samples has led to the development of a series of novel extraction chromatographic resins exhibiting enhanced metal ion retention from strongly acidic media and excellent selectivity, among them materials suitable for the isolation of 212Bi, 90Y, and 213Bi. These resins, along with extraction chromatographic materials employing functionalized supports to improve their physical stability or metal ion retention prop...

Summary: International Symposium on the Health Effects of Boron and its Compounds.

Many of you have seen me worriedly writing in the corner, sometimes furiously, trying to get down all the very important points that the conference speakers were making. It is now my task to try to sum up this conference and to give you my idea of the implications for human health on the basis of the latest information presented here. There was a wide range of papers, including the chemical and physical prop? erties of the element and its compounds; their uses; the various methods for the analysis of boron in plants, animals, and humans, as well as in air, water and soil; the biochemical and pharmacological effects of boron in plants, animals, and humans; the effects of dietary boron in experimental ani? mals; the effects of boron in human nutri? tion and human physiology; the toxicology of boric acid and borax, including develop? mental and reproductive toxicity; and the assessment of health effects among workers exposed to boric acid and borates in their

The Rendezvous architecture and language for constructing multiuser applications

When people have meetings or discussions, frequently they use conversational props : physical models, drawings, or other concrete representations of information used to enhance the exchange of information. If the participants are geographically separated, it is difficult to make effective use of props since each physical prop can only exist in one place. Computer applications that allow two or more users to simultaneously view and manipulate the same data can be used to augment human-to-human telecommunication. We have built the Rendezvous system is similar to many UIMSs or user interface toolkits in that it is intended to simplify the construction of graphical direct-manipulation interfaces. It goes beyond these systems by adding functionality to support the construction of multiuser applications. Based on experience with several large applications built with the Rendezvous system, we believe that it is useful for building conversational props and other computer-supported cooperative work (CSCW) applications. We present a list of required features of conversational props, some example applications built with the Rendezvous system, and a description of the Rendezvous system.

The Effect of Molecular Weight Distribution on the Physical Properties and Morphology of Polypropylene Stretched Tape

Stretched tape and film were made from isotactic polypropylene (iPP) homopoly mer produced with SHAC* catalyst (Shell High Activity Catalyst). The resins used were nominal 3.5 and 8.0 melt flow (MF) resins with narrow, medium, and broad molecular weight distributions (MWD). Measurements were made of tape and film physical properties as a function of MWD and process heat history. Small angle x-ray two-theta scans through the meridional direction were done to obtain Long Period Spacing (LPS) Long period spacing for an idealized semicrystalline model is the combined distance through both a crystalline lamella and the amorphous region between the lamellae. LPS was correlated to resin melt flow and MWD. Wide angle x-ray scattering (WAXS) techniques using pole figures and Hermans orientation func tions were used to determine molecular orientation. Density and physical properties (percent elongation at break, Young's modulus, and tenacity) did not change significantly as a function of MWD for the 3.5 and 8 MF tapes. The tenacities of the 8 MF tapes averaged 0.8 gm/denier less than those of the 3.5 MF tapes. The density of the 8 MF tapes was higher than that of the 3.5 MF tape density (0.9039 and 0.8998 gm/cm3, respectively) indicating a higher percent crystallinity for the 8 MF tapes. The lower molecular weights of the 8 MF resins apparently contribute to a more highly ordered structure; the latter keeps the physical properties of the tape from deteriorating as molecular weight decreases. The net result is that lower molecular weight resins (higher MF) can produce stretched tape with acceptable physical prop erties at high processing speeds.