122,959 research outputs found
A dynamic tactile sensor on photoelastic effect
No full textCertain photoelastic materials exhibit birefringent characteristics at a very low level of strain. This property of material may be suitable for dynamic or wave propagation studies, which can be exploited for designing tactile sensors. This paper presents the design, construction and testing of a novel dynamic sensor based on photoelastic effect, which is capable of detecting object slip as well as providing normal force information. The paper investigates the mechanics of object slip, and develops an approximate model of the sensor. This allows visualization of various parameters involved in the sensor design. The model also explains design improvements necessary to obtain continuous signal during object slip. The developed sensor has been compared with other existing sensors and experimental results from the sensor have been discussed. The sensor is calibrated for normal force which is in addition to the dynamic signal that it provides from the same contact location. The sensor has a simple design and is of a small size allowing it to be incorporated into robotic fingers, and it provides output signals which are largely unaffected by external disturbances
Photoelasticity based dynamic tactile sensor
Get PDFThe paper presents design, construction and testing of a photoelasticity based dynamic sensor which is capable of detecting slip as well as providing normal force information. Starting with investigations into mechanism of slip, an approximate model of the sensor has been developed. This model explains the design improvements necessary to provide continuous signal during slip. The theoretical model also helps identify various sensor parameters to characterize the sensor. The developed sensor has been compared with other existing sensors and the experimental results from the sensor have been discussed for the type of signal the sensor provides. The sensor is also calibrated for normal force. The sensor is novel in the sense that it offers dynamic slip signal as well as the normal force information from a single contact location, it provides continuous signal during slip, and it has small size which can be easily incorporated into robotic fingers. The sensor has an edge over other existing sensors that its design is simple yet it provides strong signals which are largely unaffected by external disturbances. Copyright © 2005 by ASME
A finger mechanism for adaptive end effectors
Get PDFThis paper presents design and analysis of a rigid link finger, which may be suitable for a number of adaptive end effectors. The design has evolved from an industrial need for a tele-operated system to be used in nuclear environments. The end effector is designed to assist repair work in nuclear reactors during retrieval operation, particularly for the purpose of grasping objects of various shape, size and mass. The work is based on the University of Southampton's Whole Arm Manipulator, which has a special design consideration for safety and flexibility. The paper discusses kinematic issues associated with the finger design, and to the end of the paper specifies the limits of finger operating parameters for implementing control law
Pseudocercospora rauvolfiicola A. Singh, P. N. Singh and N. K. Dubey 2022, sp. nov.
No full textPseudocercospora rauvolfiicola A. Singh, P.N. Singh and N.K. Dubey sp. nov. Fig 1–4 MycoBank: MB 834637 Etymology. Name refers to Rauvolfia, the host genus from where the fungus was isolated. Culture characteristics – Colonies after 21 days at 27 ° C on Oat Agar (OA) blackish grey, velvety, mycelium sparse, sulcate, reverse blackish grey reaching 30 mm diameter. On Potato Dextrose Agar (PDA) erumpent in centre, margin lobed, grayish black, velvety, reverse black, upto 16 mm. Pathogen on Rauvolfia serpentina Leaf spots dark blackish brown with yellowish encircling area on the upper leaf surfaces, grayish brown on lower surfaces, circular to irregular. Caespituli hypophyllous, substomatal. Mycelium internal, branched. Asexual morph: Stromata substomatal, pseudoparenchymatous, light yellowish brown to light brown, globular, few cells to 13 µm filling stomatal opening, Conidiophores 14–35.5 × 2–3 µm (x̅= 24×3, n=40) macronematous, mononematous, olivaceous brown to light brown, paler towards the tip, fasciculate in divergent fascicles (up to 14), smooth, 0–3 septate, branched, straight to curved, geniculate, sub cylindrical. Conidiogenous cells polyblastic, integrated, terminal, pale olivaceous, smooth, geniculate, scar unthickened. Conidia 9.5–56.5 × 2–3.5 µm (x̅= 36×3 µm, n =40), solitary to branched in chains, acropleurogenous, holoblastic, pale brown, subcylindrical to obclavate, apex obtuse to subacute, base obconico truncate, ramoconidium present, straight to curved, 1–5 septate, hilum unthickened. Type. India, Uttar Pradesh, Sonebhadra, leaf spots on Rauvolfia serpentina (L.) Benth.ex Kurz (Apocynaceae), 15 Dec. 2019, Archana Singh, AMH-10139 (Holotype), BHUAS/19/23 (Isotype), NFCCI 4586 (ex-type living culture), ITS, LSU, ACT and TEF sequences GenBank MT068200.1, MT102882.1, MW496125, MW496126.Published as part of Singh, Archana, Singh, Paras Nath & Dubey, Nawal Kishore, 2022, Morphology and Phylogeny of a new species Pseudocercospora rauvolfiicola on medicinal plant Rauvolfia serpentina from Sonebhadra Forest, Uttar Pradesh, India, pp. 128-138 in Phytotaxa 545 (2) on page 131, DOI: 10.11646/phytotaxa.545.2.2, http://zenodo.org/record/653463
Acanthaleyrodes elevatus Dubey, Singh & Martin, 2014, sp. nov.
No full textAcanthaleyrodes elevatus sp. nov. (Figs 1–26) Puparium. Puparium oval, 571–586 microns long, 363–410 microns wide, brown, exuviae appears white after adult emergence, without wax secretion, found on lower surface of leaves, 10–22 puparia per leaf. Body margin slightly constricted in the region of contact with leaf trichomes. Margin: Smoothly or irregularly crenulate, 15–17 crenulations in 0.1 mm. Thoracic tracheal pore area not forming a deep pore or comb, but slightly invaginated in some puparia. Caudal tracheal pore forming shallow comb at the puparial caudal end. Dorsum: Submargin not separated from dorsal disc; submarginal area with many lines; subdorsum with many longitudinal wavy ridges. Longitudinal moulting suture reaching margin and transverse moulting suture reaching submedian area. Submedian area corrugated, forming polygonal cells (Fig. 10). Abdominal segment sutures reaching outer submedian area. Median length of abdominal segment VII shorter than VI. Geminate pores present, more clearly visible on submedian area of abdominal segments. The length of caudal furrow from the base of eighth abdominal segment suture to the puparial caudal margin measured 124–167 microns long. Venter: Caudal and thoracic tracheal folds indicated with stipples (Figs 16, 17). Antennae outside of prolegs, reaching basal third of prothoracic legs, apex of antennae blunt, middle region with many minute sensilla, 41–46 microns long, keel present, 5 microns long. A pair of ventral abdominal setae present, 13–20 microns long, 21–23 microns apart. Microsetae at base of pro-, meso- and metathoracic legs present. Spiracles present. Vasiform orifice: Located on the dorsally elevated tergite of abdominal segment VIII. The elevation (distance from eighth abdominal segment suture to the base of vasiform orifice) measured 103–133 microns high. Subcircular, 27–41 microns long, 39–43 microns wide, usually as long as wide; operculum subcordate, 23–32 microns long, 25–27 microns wide, inner surface with many microtrichea (Fig. 13), covering nearly 75 % of the orifice; tip of lingula visible, setose, with a pair of setae apically. Chaetotaxy: Eight pairs of subdorsal tuberculate setae, two pair on cephalic region, three pairs-one each on pro-, meso- and metathorax, two pairs on laterad of abdominal segments IV–VIII, and one pair posterior to vasiform orifice. The length of subdorsal tuberclulate setae vary within puparium 129–157 microns long (elevation 99–122 microns + 30–35 microns long). Cephalic setae 162–183 microns (elevation 126–147 microns + setae 36 microns) long, first abdominal setae 118–185 microns (elevation 105–151 microns + setae 13–34 microns) long. Eighth abdominal setae cephalolaterad of vasiform orifice placed on tubular median elevation of eighth abdominal tergite (Figs 8, 11, 24), 77–94 microns (elevation 43–57 microns + setae 34–37 microns) long. Caudal setae positioned on margin lateral of caudal tracheal pore opening. Third instar (Fig. 19). Elongate, 465 microns long, 260 microns wide. Cephalic setae 62 microns (elevation 19 microns + setae 43 microns) long and eighth abdominal setae placed on elevated tubercles, 60 microns (elevation 42 microns + setae 18 microns) long. First abdominal setae not discernable. Caudal setae 48 microns long. Vasiform orifice circular, slightly elevated posteriorly, 34 microns long, 32 microns wide; operculum 23 microns long, 20 microns wide; lingula tip setose. Longitudinal moulting suture reaching margin and transverse moulting suture reaching submedian area, abdominal segments suture visible. Subdorsal wavy lines absent. Median length of abdominal segment VII almost equal to that of VI. Submarginal setae visible at least on posterior abdominal area. Second instar. Similar to that of third instar except in the size, 337 microns long, 113 microns wide. Margin crenulate, 18 crenulations in 0.1 mm. Cephalic setae, 46 microns (elevation 34 microns + setae 12 microns) long, caudal setae 32 microns long. Vasiform orifice circular, 32 microns long, 30 microns wide; operculum, 23 microns long, 20 microns wide. Ventral setae 6 microns long, 13 microns apart. Host plant. Bridelia retusa (L.) Spreng. (Euphorbiaceae). Holotype. INDIA: Kerala, Adivaram, 1 puparium (Fig. 23), selected second from the right of top first row amongst 9 puparia; 8.xi. 2013; A. K. Dubey, in NFIC-FRI (Fig. 23). Paratypes. Forty-one puparia on 13 slides, including 8 along with the holotype, data same as of the holotype (NHM, USDA, NFIC-FRI & AKD). Other material: 5 third instars and 4 second instars on two slides, data same as holotype. Several puparia on dry leaves deposited in A.K. Dubey collection. Etymology. The species name is derived from a Latin word “ elevatus ” that means “raised or lift up” attributing to the elevation of eighth abdominal tergite on which the orifice is opening. Remarks. Puparia of the new species resemble both A. callicarpae and A. styraci Takahashi in the presence of tuberculate setae on dorsum and subcircular vasiform orifice. It differs from both of these by the presence of 11 pairs of tuberculate setae, and absence of median tubercles on the cephalothorax and abdomen. It also differs from both in that the caudal margin is not produced posteriorly, whereas in both A. callicarpae and A. styraci the vasiform orifice has a posteriorly produced margin. The puparia of this new species were found on the lower surfaces of leaves, intermingled with puparia of Aleurotrachelus tuberculatus Singh. They could be distinguished from A. tuberculatus by their white or dark brown appearance whereas those of A. tuberculatus are black. The immatures (second and third instars) of A. tuberculatus are white but distinguishable by the presence of long submedian setae on cephalothorax and by the wax glands at the base of the marginal teeth.Published as part of Dubey, Anil Kumar, Singh, Sudhir & Martin, Jon H., 2014, Acanthaleyrodes elevatus sp. n. (Hemiptera: Aleyrodidae) from India, with key to species and discussion of tuberculate setae, pp. 33-48 in Zootaxa 3881 (1) on pages 36-41, DOI: 10.11646/zootaxa.3881.1.3, http://zenodo.org/record/28738
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Square Dancing with the Stars to Enhance Dynamic Hirschman Linkages?
No full textIn this Presidential Address, the author takes the reader on a reconnaissance of his life and time as a regional scientist. He points out scenery he found scintillating along the way, hoping that some may pick up the banner and chew on a few of the ideas for a while. He suggests a revisit to Albert O. Hirschman’s notion of key sectors and more empirical analysis related to Marcus Berliant’s and Masahisa Fujita’s notion of knowledge creation and transfer.Presidential Address, San Antonio, Texas, March 29, 2014 (53rd Meetings of the Southern Regional Science Association
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Introduction to the Special Issue of the 16th ACM Workshop on Adaptive and Reflective Middleware (ARM)
No full textDubey, A.; Garcia-Valls, M. (2019). Introduction to the Special Issue of the 16th ACM Workshop on Adaptive and Reflective Middleware (ARM). Journal of Systems Architecture. 97. https://doi.org/10.1016/j.sysarc.2019.03.006S97García-Valls, M., Dubey, A., & Botti, V. (2018). Introducing the new paradigm of Social Dispersed Computing: Applications, Technologies and Challenges. Journal of Systems Architecture, 91, 83-102. doi:10.1016/j.sysarc.2018.05.007Rahman, M., Rahman, A., Hong, H.-J., Pan, L.-W., Sarwar Uddin, M. Y., Venkatasubramanian, N., & Hsu, C.-H. (2019). An adaptive IoT platform on budgeted 3G data plans. Journal of Systems Architecture, 97, 65-76. doi:10.1016/j.sysarc.2018.11.002Rosa, N. S., Campos, G. M. M., & Cavalcanti, D. J. M. (2019). Lightweight formalisation of adaptive middleware. Journal of Systems Architecture, 97, 54-64. doi:10.1016/j.sysarc.2018.12.00
Letter from unknown writer to Jesse L. Boyce
No full textLetter to Jesse L. Boyce from unknown author (possibly Jack) about the investigation into the powder magazine located in the Grand Canyon. Some personal news is included in the letter such as the writer's marriage to the daughter of C.A. Taylor, former Supervisor of Cochise County
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