Strip Bundles Research Articles

ESTIMATION OF SENSOR OFFSETS FOR A UAV PLATFORM USING TIEPOINTS ONLY

Abstract. In a UAV system, physical sensor offsets occur between an observation sensor and a GPS/IMU sensor which represents the position of UAV. The difference of angle between the GPS/IMU sensor’s axis and the observation sensor’s axis is referred to as boresight angle. The difference in physical position between the two is referred to as lever-arm. It is important to obtain accurate offset values in order to utilize UAVs in rapid mapping manner. Due to the sensor offsets, misalignment error can be caused when generating a mosaic image. Offset values can be measured by using extensive ground control points. However, this is very costly and time-consuming. In this study, we describe an estimation method for sensor offsets using tie-points and re-weighted least square estimation method. The proposed method consists of 5 steps. Firstly, a frame images for the target area were classified into image strips based on the kappa value of initial EOPs (Exterior Orientation Parameters), after which tie points were extracted between adjacent images. Secondly, strip bundle adjustment was performed to update initial EOPs using images with the same flight direction. Thirdly, tie-points between adjacent strips were extracted. Fourthly, block bundle adjustment was performed in all images, using all extracted tie-points. Finally, a mosaic image is generated using the EOPs value to which the estimated sensor offset is applied. From this study, we confirmed that the sensor offset of the platform could be estimated only with the tie-points extracted between adjacent images. And we confirmed that misalignment was adjusted when generating mosaic image. We expect that our research makes UAV system to be operated more fluently.

Zigzag strip bundles and crystals II

Zigzag strip bundles are combinatorial models realizing the crystals B(∞) and the highest weight crystals B(λ) over quantum affine algebras Uq(g), and they are closely related with Nakajima monomials and Kashiwara embeddings of specific type. In this paper, we introduce new zigzag strip bundles for Uq(g), which we call reverse zigzag strip bundles in order to distinguish from the previous ones, and we give explicit 1-1 correspondences with the set of Nakajima monomials and the image of Kashiwara embedding which are different from those appeared in the study of the zigzag strip bundles. Another main result is to give different points of view about zigzag strip bundles and reverse zigzag strip bundles. Indeed, the previous 1-1 correspondences between the sets of zigzag strip bundles or reverse zigzag strip bundles, and the sets of Nakajima monomials or images of Kashiwara embeddings were determined based on the number of blocks in the columns of these strip bundles. In our work, we use the number of blocks in the rows of zigzag strip bundles and reverse zigzag strip bundles to provide characterizations of Nakajima monomials and images of Kashiwara embeddings that differ from the previous ones. That is, we give characterizations of Nakajima monomials and Kashiwara embeddings of 4 types. Further, we discuss the connection between zigzag strip bundles and reverse zigzag strip bundles.

Effects of Twisting and Surface Finish on the Mechanical Properties of Natural Gut Harp Strings.

Natural gut harp strings are made from twisted bundles of gut strips, which are dried, ground, and varnished. The effects of varying the twist angle and surface finishing on the mechanical properties of gut harp strings have been explored. Strings were tested over a range of twist angles from 23.5∘ to 58.3∘, and with all four combinations of ground or unground and varnished or unvarnished surface finishing. The principal effects of varying the degree of twisting were that the breaking strength and tensile Young's modulus both fell as the twist angle was increased. String makers must therefore make a compromise between sound quality and string strength and durability. Leaving the string unvarnished dramatically increased the sensitivity to changes in humidity, which, in turn, affected the thermal tuning sensitivity and creep behaviour. Grinding the string surface prior to varnishing had no significant effect on the behaviour, but did make some difference to the thermal tuning sensitivity if the string was left unvarnished. Increasing the humidity frequently triggered episodes of additional string creep. There appeared to be a threshold effect, with the additional creep triggered when the string linear density exceeded its previous maximum. When the string was not creeping, there appeared to be a strong coupling mechanism between changes in the linear density and complementary changes in the string tension, such that there was almost no net effect on the string frequency. This behaviour was independent of the twist angle and the surface finishing, suggesting that whatever the coupling mechanism was, it was not dependent on the twisted structure of the string.

Strip bundle realization of the crystals over Uq(D4(3))

We introduce new combinatorial models called strip bundles for the quantum affine algebra Uq(D4(3)) and give new realizations of the crystal B(∞) and the highest weight crystals B(λ) over Uq(D4(3)) in terms of strip bundles. In these strip bundle realizations, the highest weight crystal B(Λ1) of the natural representation V(Λ1) over the quantum finite algebra Uq(G2) plays a crucial role.

Strip bundle realization of the crystals over Uq(G2(1))

Motivated by the zigzag strip bundles which are combinatorial models realizing the crystals B(∞) for the quantum affine algebras Uq(g), where g=Bn(1),Dn(1),Dn+1(2),Cn(1), A2n−1(2),A2n(2), we introduce a new combinatorial model called strip bundles for the quantum affine algebra Uq(G2(1)). We give new realizations S(∞) and S(λ) of the crystal B(∞) and the highest weight crystals B(λ) over Uq(G2(1)) using strip bundles, and as subsets of S(∞) and S(λ), we also give realizations of the crystal B(∞) and the highest weight crystals B(λ) over the quantum finite algebra Uq(G2). Moreover, we give characterizations of the image of the crystal embedding Ψi and the connected component C1 in the set M of all Nakajima monomials which are isomorphic to the crystal B(∞) over Uq(G2(1)).

Динаміка балансу антиоксидантно-прооксидантних механізмів у внутрішніх органах під впливом артеріального джгута і реперфузії кінцівки

В сучасних умовах значно зросла частота травм із масивною зовнішньою кровотечею, які вимагають негайного накладання артеріального джгута на кінцівку з безпечним терміном до 2-х год. В окремих роботах показана можливість розвитку ускладнень як під джгутом, так і внаслідок реперфузії кінцівки. Однак її влив на антиоксидантно-прооксидантний баланс внутрішніх органів вивчений недостатньо.Мета дослідження. З’ясування впливу двогодинного застосування артеріального джгута і реперфузії кінцівки на динаміку антиоксидантно-прооксидантних механізмів у печінці, легенях і нирці.Матеріали і методи. Експерименти виконано на 36 нелінійних щурах-самцях масою 200-220. У дослідних групах під тіопепнтало-натрієвим знечуленням (40 мг·кг-1) проксимально на ліву лапку накладали смужку джгута «SWAT-T» шириною1 см на 120 хв. Тварин дослідних груп виводили з експерименту через 60 хв, 120 хв, 24 год, 7 і 14 діб після реперфузії. В контрольній групі тварин вводили в наркоз, застосовуючи еквівалентну дозу тіопенталу натрію, накладали джгут без припинення кровотоку і в подальшому виводили з експерименту через 2 год. Для дослідження брали печінку, нирку та легені. У гомогенатах зазначених органів визначали вміст реагентів до тіобарбітурової кислоти (ТБК-активних продуктів ПОЛ), активність каталази. За співвідношенням активність каталази / вміст ТБК-активних продуктів ПОЛ розраховували антиоксидантно-прооксидантний індекс (АПІ).Результати досліджень та їх обговорення. У контролі інтенсивність ліпопероксидації і активність каталази збільшувалися від печінки до нирки і легень. Після реперфузії кінцівки в досліджуваних органах відмічалося зростання інтенсивності ліпідної пероксидації, про що свідчило накопичення ТБК-активних продуктів, яке в печінці було вірогідно більшим, ніж у контролі, до 14 доби, в легенях – до 7 доби, в нирці – протягом 24 год. Активність каталази в органах була істотно більшою від контролю у всі терміни спостереження з максимумом через 24 год. Показник був вірогідно більшим у нирці. Величина АПІ в нирці і легенях підвищувалася до 24 год після реперфузії кінцівки і до 14 доби знижувалася, не досягаючи рівня контролю. В печінці динаміка показника була коливальною з першим підвищенням через 1 год, зниженням – через 2 год і подальшим зростанням до 14 доби. Наведені дані вказують на тривале напруження адаптаційно-компесаторних механізмів, спрямованих на усунення патогенних чинників, зумовлених накладанням джгута, двогодинною ішемією та подальшою реперфузією кінцівки. Отримані результати вимагають подальшого поглибленого вивчення, проте вже тепер вказують на небезпечність двогодинного накладання джгута з позиції системного впливу на організм і вимагають додаткових заходів профілактики та корекції.Висновки. Реперфузія кінцівки після двогодинного артеріального джгута супроводжується тривалою активацією процесів ліпідної пероксидації у печінці, нирках і легенях, що проявляється статистично вірогідним зростанням вмісту ТБК-активних продуктів, який в печінці перевищує контрольний рівень до 14-ї доби після реперфузії, в нирці – через 24 год, в легенях – через 7 діб. Посилення процесів ПОЛ відбувається на тлі підвищення активності каталази у всіх органах, яка досягає максимуму через 24 год і не знижується до рівня контролю через 14 діб. Баланс антиоксидантно-прооксидантних процесів в досліджуваних органах зміщений в бік посилення антиоксидантних механізмів, що вказує на тривалий оксидативний стрес в постреперфузійному періоді.

Strip Bundles and the Highest Weight Crystals Over Quantum Infinite Rank Affine Algebras

We give new realizations of the highest weight crystals B(λ) over the quantum infinite rank affine algebras U q (A ∞), U q (B ∞), U q (C ∞), and U q (D ∞) using strip bundles, which are related with Nakajima monomials.

Zigzag Strip Bundles and the Crystal B(∞) for Quantum Affine Algebras

We give a new realization of the crystal B(∞) of (, , or ) using the combinatorial objects zigzag strip bundles. Moreover, we study the relation between zigzag strip bundle realization, Nakajima monomial realization, and polyhedral realization of B(∞).

Zigzag strip bundles and highest weight crystals

Zigzag strip bundles are new combinatorial models realizing the crystals B(∞) for the quantum affine algebras Uq(g), where g=Bn(1),Dn(1),Dn+1(2),Cn(1),A2n−1(2),A2n(2). In this paper, we give new realizations of the crystal bases B(λ) for the irreducible highest weight modules V(λ) over quantum affine algebras Uq(g) using zigzag strip bundles. Further, we discuss the connection between zigzag strip bundle realization, Nakajima monomial realization, and polyhedral realization of the crystals B(λ).

Zigzag strip bundles and crystals

We introduce new combinatorial models, called zigzag strip bundles, over quantum affine algebras Uq(Bn(1)), Uq(Dn(1)) and Uq(Dn+1(2)), and show that the sets of all zigzag strip bundles for Uq(Bn(1)), Uq(Dn(1)) and Uq(Dn+1(2)) realize the crystal bases B(∞) of Uq−(Bn(1)), Uq−(Dn(1)) and Uq−(Dn+1(2)), respectively. Further, we discuss the connection between zigzag strip bundle realization, Nakajima monomial realization, and polyhedral realization of the crystal B(∞).

Nakajima Monomials, Strip Bundles, and the Crystals B(∞) Over U q (B ∞), and U q (C ∞), and U q (D ∞)

In this article, we give two new realizations of the crystal base B(∞) of the negative part of the quantum generalized Kac–Moody algebra U q (𝔤) (𝔤 =B ∞, C ∞ or D ∞) using Nakajima monomials and strip bundles, respectively. Furthermore, we discuss the relation between monomial realization and strip bundle realization.

Role of the Cytoskeleton in Choanoflagellate Lorica Assembly

Cell division in Acanthoeca spectabilis produces a "naked" motile daughter cell (juvenile) that settles onto a surface and deposits siliceous costal strips that are stored extracellularly in bundles. When complete, the bundles of strips are assembled in a single continuous movement to form a basket-like lorica. Assembly can be divided into four overlapping stages. Stage 1 entails the left-handed rotation of strips at the anterior end while the posterior end remains stationary. Stage 2 includes the posterior protrusion of the cell to form a stalk. Stage 3 involves the anterior extension of the spines, and Stage 4 the dilation of the lorica chamber and deposition of the organic investment. Scanning electron microscopic images reveal a one-to-one association between the moving bundles of strips and the anterior ring of lorica-assembling tentacles. Treatment with microtubule inhibitors produces "dwarf" cells that lack stalks, have their spines extended, and possess collars but lack flagella. Treatment with microfilament (actin) inhibitors prevents extension of the anterior spines. These experiments demonstrate that posterior cell extension is primarily mediated by microtubules whereas extension of the spines is controlled by the actin cytoskeleton. The processes of cytoskeletal rotation and extracellular costal strip movement are compared, respectively, with rotation of nuclei in animal embryos and movement of mammalian cells over surfaces.

Depth profile of UV-induced wood surface degradation

The depth profile of weathering effects on wood was studied after the laboratory ultraviolet exposure of fir-wood. The ‘thin strip’ method (ie the measurement of changes in tensile properties of microtomed wood sections) was modified in terms of exposure of batches of strips packed in bundles and exposed in a QUV apparatus. The bundles of strips were exposed untreated, covered with surface strips that had been impregnated with chromium (VI) trioxide or Fe(III) nitrate, or protected with free films of clear stain with photostabilisers and without photostabilisers.

Exercise catecholamine concentrations inhibit acetylcholine release in airways

SummaryWe determined the effects of exercise induced concentrations of epinephrine (E) and norepinephrine (NE) on acetylcholine (ACh) release and smooth muscle contraction. To determine ACh release, trachealis strip bundles were suspended in 2 ml tissue baths in the presence of neostigmine (10−6M), guanethidine (10−5M) and atropine (10−7M), and stimulated by electrical field stimulation (EFS; 20 V, 0.5 ms, 0.5 Hz, for 15 min). EFS‐induced ACh release was measured by high‐performance liquid chromatography coupled with electrochemical detection. Concentration responses to E and NE (10−8 to 10−5M) were determined. In time‐control tissues, ACh release averaged 8.2 ± 0.9 pmol/g/min. Epinephrine caused significant inhibition of ACh release at concentrations of 10−7M or greater and NE at 10−6M or greater. E‐ and NE‐induced inhibition of ACh release was attenuated by the α2‐adrenoceptor antagonist idazoxan (10−6 M) but not by the α2‐antagonist prazosin (10−6M) nor the β‐antagonist propranolol (10−6M). We determined if E and NE had inhibitory actions on smooth muscle by examining their effect on the ACh concentration‐response curve of trachealis. E (10−6M) inhibited contraction only at 10−7M ACh, i.e. when muscle tension was low. NE had no effect. Exercise induced concentrations of E inhibit cholinergically mediated bronchospasm primarily by α2‐mediated prejunctional inhibition of ACh release and, to a lesser degree, by a post junctional effect on airway smooth muscle. NE only inhibits ACh release but not significantly at the concentrations achieved during exercise.

ACh release from horse airway cholinergic nerves: effects of stimulation intensity and muscle preload.

This study was conducted to determine the effects of stimulation parameters and muscle preload on acetylcholine (ACh) release induced by electrical field stimulation (EFS) of horse airway cholinergic nerves. Trachealis strip bundles were prepared and suspended in 2-ml tissue baths. The tissues were stimulated three to five times for 30 min each. Increasing frequency (0.5-16 Hz) and voltage (5-20 V) increased ACh release; increasing pulse duration (0.5-3 ms) had only a minor effect. Alterations in muscle preload (2-20 g) had no effect on ACh release. ACh release was fairly constant for up to five repeated stimulation periods with the same EFS parameters. Stimulation of the tissues for 15 min released the same amount of ACh as 30 min if the amount was expressed as picomoles per gram per minute, suggesting that ACh release rate was constant during the 30-min period of stimulation. Atropine (10(-6) M) potentiated the release of ACh four- to fivefold, presumably by removing the autoinhibitory effect of ACh on the cholinergic nerves. Tetrodotoxin (10(-6) M) abolished the EFS-induced ACh release.

Developmental studies on the loricate choanoflagellateStephanoeca diplocostata Ellis VI. Effects of silica replenishment on silica impoverished cells

Stephanoeca diplocostata has a facultative requirement for silica in that silica starvation does not inhibit growth as measured by increase in cell numbers. In spite of the absence of a lorica silica impoverished protoplasts still divide in the characteristic ‘tectiform’ manner and a juvenile protoplast, when released from the parent cell, still extends its lorica assembling tentacles despite the absence of costal strips with which to produce a lorica. Replenishment of silica to silica starved cells in mid to late exponential phase cultures results in a decrease in the growth rate but at the same time silica is taken up and utilised for the deposition of costal strips. Mature costal strips are extruded and accumulated in bundles of 5–8 on the surface of the protoplast but are not passed to the top of the collar as would be expected in silica enriched loricate cells. Eventually silica replenished protoplasts use the bundles of costal strips to assemble loricae for themselves. In early exponential phase cultures naked protoplasts are capable of division whilst at the same time depositing costal strips in preparation for subsequent lorica assembly. An undamaged protoplast deprived of its lorica by ultrasonic treatment also ultimately replaces the lost lorica. The manner in which the tectiform mode of costal strip accumulation and lorica assembly is modified to allow a cell to produce its own lorica is discussed.

Model of double helical liquid flow in dense bundles of twisted strips

Model of double helical liquid flow in dense bundles of twisted strips

Developmental studies on the loricate choanoflagellateStephanoeca diplocostata ellis

Cells ofStephanoeca diplocostata comprise a colourless, flagellated, protoplast lodged in a lorica made of siliceous costae. The single anterior flagellum creates a water current from which bacteria and other food particles are filtered by the collar and ingested by linguiform pseudopodia that arise from the protoplast at the base of the collar. A waist divides the lorica into two chambers, the anterior of which contains three transverse and 17–20 longitudinal costae whereas the posterior chamber comprises two systems of spirally deflected costae and on some cells a pedicel at the hind end. Between 150–185 costal strips of similar length form the lorica. A thin investment covers the inner surface of the posterior chamber and lower part of the anterior chamber and joins with the protoplast at the level of the waist. Costal strips are produced within membrane-bounded vesicles in the peripheral cytoplasm and, although the origin of these vesicles is unknown, there is usually a close association with the Golgi apparatus. Once complete, strips are apparently released sideways through the plasmalemma into the cavity of the posterior lorica chamber. Later, bundles of strips are transferred to the top of the inner surface of the collar where they collectively form a horizontal ring. When sufficient strips to form a lorica have been accumulated at the top of the collar, cell division proceeds.

Month in the Patent Office

In cellular panel or like constructional work wherein sheets of plywood or other material are spaced apart by sinuous web elements outlining the cells and joined at opposite edges to the sheets, perforations are provided in the web elements between their edges to give communications between all the cells, the cells being also vented to the exterior of the structure. In fig. 1, plywood sheets 1, 2 are connected by undular web elements comprising thinner plywood strips 3 bonded together at 4 to form cells 6, the strips having perforations 7 either between or through the bonds 4. Fillets 8 may be provided at the edges of the structure, and are vented by perforations 9; further perforations may be provided in the sheets 1, 2. The cells may be of hexagonal or other form. The web elements may be formed by perforating bundles of strips, or by bundling sheets, perforating the sheets along parallel lines, and cutting the bundled sheets between and parallel to the lines of perforations; the sheets may be bonded together along lines which are staggered in alternate sheets, so that when a bundle of strips is cut off, it may be expanded to form the cellular outline. The construction is applicable to surface construction on aircraft. Specifications 556,620 (Group XXIII), and 625,037 are referred to.