Arm Length Research Articles

Research on the intrinsic phase difference of Rayleigh scattering in distributed acoustic sensing

The differential cross-phase multiply (DCM) demodulation algorithm based on a 3 × 3 coupler is commonly employed in distributed acoustic systems (DAS) to recover phase information along the sensing fiber. This study investigates the amplitude-spatial resolution response characteristics of the DCM algorithm using 3 × 3 coupler demodulation. Firstly, we theoretically establish the variation of demodulation amplitude in DAS systems due to the intrinsic phase of the signal. Subsequently, we analyze the amplitude-pulse width response curves of the DCM algorithm based on the distribution of demodulated phase error obtained from both experimental and simulation data. The findings reveal a double peaks phenomenon in the amplitude response curves of the DCM demodulation algorithm based on 3 × 3 couplers. We also explore the amplitude response curves for multiple pulse widths and observe that, under the same arm length difference conditions, the double peaks persist. However, this double peak phenomenon is eliminated when the pulse width is less than 21 ns. Therefore, when the width determined by the pulse is greater than 40% of the difference between the light paths, the demodulation will appear double peaks phenomenon.

Design optimization of a flexure spring used in small-sized ultra-precise optical instrument

Small-sized ultra-precise optical devices require compact compliant ortho-planar springs (COPS) aka. flexure springs, for precise, frictionless linear motion which depends highly on the design. A self-developed arm-hinge-linked design, named “Panto-style” flexure spring was optimized by selecting 5 design parameters (thickness: t, hinge width: W, arm length 1 and 2: L1 and L2, arm angle: Ө) and constructing sets of design of experiments (DOEs).Signal-to-noise ratio (SNR) and response surface model (RSM) regression were obtained in terms of axial deformation. The highest response from the main effects plot was the thickness (t), followed by hinge width (W). The angle of the arm (Ө), was considered a non-relevant parameter.The parameters optimization was implemented with constraint input and output. Kinetostatic performances (axial/radial deformations, and stress) were predicted, validated, and compared (RSM, KNN, FE simulations, and experiments) using the optimized design.The average value of KNN and RSM (KNN + RSM) increased the accuracy of axial deformation value compared to RSM alone. To conclude, RSM design parameter optimization followed by KNN + RSM has successfully predicted the output results (axial/radial deformation and stress) confirmed both numerically and experimentally.

Optimized Design of Lithium Niobate Tuning Forks for the Measurement of Fluid Characteristic Parameters.

The unique double-cantilever beam structure and vibration mode of the tuning fork enable the measuring of fluid density and viscosity synchronously in a decoupling manner. Therefore, it is widely employed in oil and gas development and in petrochemical, food, textile, and other industries. In this paper, quality factors are used to characterize the energy losses of lithium niobate tuning forks when vibrating in a fluid, and the influence parameters, such as length, width, and thickness of the tuning fork arm, etc., of different quality factors are examined with a focus on the viscous quality factor of the fluid. The optimized design of lithium niobate tuning fork dimensions is carried out on this premise, and the analytical solution of the optimal dimension of the lithium niobate tuning fork in the air is obtained. Secondly, the optimal dimension of the lithium niobate tuning fork in fluids is given out by finite element simulation, and the sensitivity of the optimized fork to the viscosity of fluids is investigated. The results show that the optimized tuning fork has a higher quality factor, and thus has a larger parameter measurement range as well as being more sensitive to the change in the fluid density and viscosity. Therefore, the results are of great significance for guiding the preparation and practical application of lithium niobate tuning forks.

Octopus-inspired sensorized soft arm for environmental interaction.

Octopuses can whip their soft arms with a characteristic "bend propagation" motion to capture prey with sensitive suckers. This relatively simple strategy provides models for robotic grasping, controllable with a small number of inputs, and a highly deformable arm with sensing capabilities. Here, we implemented an electronics-integrated soft octopus arm (E-SOAM) capable of reaching, sensing, grasping, and interacting in a large domain. On the basis of the biological bend propagation of octopuses, E-SOAM uses a bending-elongation propagation model to move, reach, and grasp in a simple but efficient way. E-SOAM's distal part plays the role of a gripper and can process bending, suction, and temperature sensory information under highly deformed working states by integrating a stretchable, liquid-metal-based electronic circuit that can withstand uniaxial stretching of 710% and biaxial stretching of 270% to autonomously perform tasks in a confined environment. By combining this sensorized distal part with a soft arm, the E-SOAM can perform a reaching-grasping-withdrawing motion across a range up to 1.5 times its original arm length, similar to the biological counterpart. Through a wearable finger glove that produces suction sensations, a human can use just one finger to remotely and interactively control the robot's in-plane and out-of-plane reaching and grasping both in air and underwater. E-SOAM's results not only contribute to our understanding of the function of the motion of an octopus arm but also provide design insights into creating stretchable electronics-integrated bioinspired autonomous systems that can interact with humans and their environments.

Development and validation of an updated PICC length prediction formula based on anteroposterior chest radiographs for the ultrasound-guided bedside placement.

Bedside peripherally inserted central catheter (PICC) placement is sometimes required when the patient's intrahospital transport is restricted, and the ideal catheter length prediction is needed. This study aimed to develop an updated formula that predicts the optimal length of a PICC based on anteroposterior chest radiographs (AP-CXRs). This retrospective study collected PICC procedure data as the training and validation sets in three hospitals, including cubital crease-puncture point distance (CP), the actual PICC length (aCL), and the approach side. Horizontal and vertical measurement variables were set on the AP-CXRs. Two dependent variables were ipsilateral upper arm length (AL) and ideal truncal catheter length (iTCL). Simple and multiple regression analyses were used for formula development, and it was applied to the test set to evaluate the length prediction performance. The study included 309 patients in the training and validation sets and 91 intensive care patients in the test set. The final derived formula was: (AL + iTCL = CP + estimated PICC length, cm) = 19.831 - 0.062 × (contralateral clavicle length, cm) + 0.255 × (2nd ribs horizontal distance, cm) + 0.720 × (humero-vertebral distance, cm) + 0.761 × (thoraco-carinal distance, cm) + 1.024 × (the vertical distance of two vertebral body units, cm). (If approaching from the left, add 2.843cm, and if female, subtract 0.821cm.) In the test set, there was no case of length prediction failure. Moreover, the catheter tip position was evaluated as optimal in 82 cases (90.1%). This study's results suggest an updated formula to predict the ideal PICC length using only AP-CXRs for bedside placement.

A review of the genus Muusoctopus (Cephalopoda: Octopoda) from Arctic waters

We report two Arctic species of incirrate octopods new to science. One is formally described here as Muusoctopus aegir Golikov, Gudmundsson & Sabirov sp. nov. while the other, Muusoctopus sp. 1, is not formally described due to a limited number of samples (all are immature individuals). These two species differ from each other, and from other Muusoctopus, especially in: 1) absence of stylets (in M. aegirsp. nov.); 2) proportions of mantle and head; 3) funnel organ morphology (W-shaped with medial and marginal limbs of equal length in M. aegirsp. nov., or medial are slightly longer; V V-shaped with medial limbs slightly longer and broader than marginal in Muusoctopus sp. 1); 4) sucker and gill lamellae counts; 5) relative arm length and sucker diameter; and 6) male reproductive system relative size and morphology. Species of Muusoctopus now comprise four of 12 known Arctic cephalopods. Additionally, this study provides: a) new data on the morphology and reproductive biology of M. johnsonianus and M. sibiricus, and a diagnosis of M. sibiricus; b) the equations to estimate mantle length and body mass from beak measurements of M. aegirsp. nov. and M. johnsonianus; c) a cytochrome c oxidase subunit I gene barcode for M. sibiricus; d) new data on the ecology and distribution of all studied species; and e) a data table for the identification of northern North Atlantic and Arctic species of Muusoctopus.

Two‐sided productivity heterogeneity, firm boundaries, and assortative matching

AbstractWe consider a market where each firm is created by the combination of two complementary assets that are heterogeneous in their productivity. After assets match endogenously, their owners choose between two ownership structures: centralized organization (integration) and arm's length organization (nonintegration). Our main focus is on the interplay between productivity heterogeneity and firm boundary decisions. When firms choose between distinct ownership structures, the standard single‐crossing condition that guarantees positive assortative matching may fail to hold. We provide a novel condition—the congruent marginal contributions property—which guarantees monotone matching with respect to asset productivity. Furthermore, we provide conditions under which integration at the bottom of the productivity ladder is the market equilibrium; an organizational pattern that has been largely unexplored by the theoretical and empirical literature. We investigate the effect of model primitives on the equilibrium distribution of output. Moreover, our model offers interesting testable implications regarding firm boundary decisions.

Performance Evaluation of an Immersive Virtual Reality Application for Rehabilitation after Arthroscopic Rotator Cuff Repair.

Few studies have evaluated the effectiveness of shoulder rehabilitation in virtual environments. The objective of this study was to investigate the performance of a custom virtual reality application (VR app) with a stereophotogrammetric system considered the gold standard. A custom VR app was designed considering the recommended rehabilitation exercises following arthroscopic rotator cuff repair. Following the setting of the play space, the user's arm length, and height, five healthy volunteers performed four levels of rehabilitative exercises. Results for the first and second rounds of flexion and abduction displayed low total mean absolute error values and low numbers of unmet conditions. In internal and external rotation, the number of times conditions were not met was slightly higher; this was attributed to a lack of isolated shoulder movement. Data is promising, and volunteers were able to reach goal conditions more often than not. Despite positive results, more literature comparing VR applications with gold-standard clinical parameters is necessary. Nevertheless, results contribute to a body of literature that continues to encourage the application of VR to shoulder rehabilitation programs.

Investigation of an inline fiber Mach-Zehnder interferometer based on hybrid joints of core-offset and peanut-shape for refractive index sensing

An inline fiber Mach-Zehnder Interferometer (MZI) that consisted of a standard single-mode fiber sandwiched between a core-offset and a peanut-shape joint is fabricated for the purpose of refractive index (RI) sensing. After one of the core-offset joints is replaced by a peanut-shape joint in an inline fiber MZI with the core-offset pair, the influence of the interference performance caused by the relative offset direction of the two core-offsets is avoided. The RI sensing characteristics under different core-offset displacement and interference arm length are studied. After bending the inline fiber MZI, the interference spectra become more stable, and the RI sensing performance is markedly improved. The RI sensitivity of −167.27 nm/RIU with a resolution of 2.39 × 10-4 RIU is achieved within the measured RI range of 1.333–1.373.

Slow-wave-enhanced on-chip Michelson interferometer sensor.

We experimentally demonstrated slow-wave-enhanced phase and spectral sensitivity in asymmetric Michelson interferometer (MI) sensors. Compared to Mach-Zehnder interferometers (MZI) that experimentally demonstrated a phase sensitivity of 84,000 rad/RIU-cm, the reflected path enhancement of the optical path length coupled with slow light enhancement with photonic crystal waveguides in on-chip slow light Michelson interferometer sensors resulted in experimentally demonstrated phase sensitivity of 277,750 rad/RIU-cm with theoretical phase sensitivity as high as 461,810 rad/RIU-cm, at the same form factor as the MZI of identical interferometer arm lengths.

Textile-based quad-band electromagnetic absorber design for wearable applications

In this article, a textile-based quad-band electromagnetic absorber (TQA) is presented for wearable applications in the S-band frequency region. The proposed TQA consists of two asymmetric X-shaped resonators (AXRs) with different arm lengths placed on fully grounded denim fabric. Since each arm of the two AXRs excites a different resonance mode, four distinctive absorption bands can be achieved by adjusting the arm lengths. The proposed structure with optimal design parameters, designed and optimized using CST Microwave Studio Suite v.2021, provides over 0.99 absorption peaks at 2.68, 2.80, 3.00, and 3.18 GHz frequencies in the simulation environment. Also, an efficient lumped equivalent circuit model is extracted for the absorber to demonstrate the principle of the quad-band operation in the respective frequencies. In addition, a good agreement between simulated and measured results is observed and thus the numerical design is validated. More importantly, to the best of the authors’ knowledge, this is the first textile based absorber design that provides absorbance in four different frequency bands.

Adjusment Basketball Facilities and Infrastructure for Children 10-12 Years Old Through Anthropometric Comparison

Implementation of physical education is allowed to modify instructional media. Physical education requires facilities and infrastructure specifically designed to promote physical activity. The aim of this research is to develop adjustments to basketball facilities and infrastructure for children aged 10-12 years through anthropometric comparisons. This research uses simple development research because it is still in the form of an initial design. The total research sample involved was 691 people. The sample underwent height, arm span, leg length, and finger span measurements. The results are that the comparison ratio of facilities and infrastructure for adults and children aged 10-12 years is the same as the anthropometric ratio of the study sample. Sports facilities and infrastructure adjustments are indispensable to the growth and development of children aged 10-12. By providing spaces where children can engage in physical activities tailored to their age and interests, we lay the foundation for healthy lifestyles, holistic skill development, cognitive growth, and emotional well-being.

METHODOLOGICAL TOOLS FOR MAKING MANAGEMENT DECISIONS ON TRANSFER PRICING

The article systematises methodological tools for making managerial decisions on transfer pricing. An analysis of domestic scientific works on the study of the list of methodological tools for determining transfer prices is carried out. It is found that transfer pricing researchers in the system of management accounting agree on a list of methods for determining transfer prices, including methods for determining transfer prices on the basis of market prices, on the basis of cost prices determined by marginal/standard/full costs or on a double basis, and on the basis of contract prices. Researchers of transfer pricing in the tax system are united in this approach and work with the methods (comparable uncontrolled price (as sales); resale price; "cost plus"; net profit; profit distribution) recommended by the OECD Transfer Pricing Guidelines for Multinational Enterprises and Tax Administrations and established by the Tax Code of Ukraine when checking the conformity of the terms of controlled transactions with the arm's length principle. Identify the conditions under which transfer pricing methods are used in domestic practice. The advantages and disadvantages of using certain transfer pricing methods are identified. To test and thoroughly analyse the transfer pricing methods, business operations of an agro-industrial enterprise are developed. The characteristics and limitations of the application of a particular transfer pricing method are identified. These transactions clearly illustrate the characteristics, advantages and disadvantages of using each transfer pricing method to verify the arm's length transfer price. The author demonstrates the need for adjustments in cases where the transfer price or profitability of a controlled transaction is not in line with the arm's length principle. The article emphasises the need for proportional adjustment of the tax base as a means of avoiding double taxation. Taking into account the systematisation of legal and regulatory provisions on transfer pricing, peculiarities, advantages and disadvantages of using certain methods, the author proposes a general scheme for making managerial decisions in the field of methodological management of transfer pricing operations.

Control of magnon-magnon coupling in Ni80Fe20 nanocross arrays through system dimensions

Hybrid magnonics, founded on the coherent interplay between magnons and various quasiparticles, provides avenues for quantum transduction and the seamless transmission of coherent information. Magnon-magnon coupling, which exhibits remarkable coupling strength advantages over light-matter interactions, has emerged as a promising field. This research investigates magnon-magnon coupling in Ni80Fe20 nanocross arrays, with a focus on controlling the anticrossing phenomenon. Through a methodical adjustment of the nanocross arm length, it becomes possible to fine-tune the strength of coupling. The significance of the observed effect becomes evident when examining the power and phase profiles of distinct spin-wave (SW) modes in close proximity to and at a considerable distance from the anticrossing point. The research contributes to bridging the gap in hybrid quasi-particle interactions and offers insights into magnon-magnon coupling control. The findings open avenues for efficient magnon-based technologies and systems enabling efficient control of SW propagation characteristics and coupling, with implications for efficient quantum information processing architectures.

The Impact of Occlusion on Depth Perception at Arm's Length.

This paper investigates the accuracy of Augmented Reality (AR) technologies, particularly commercially available optical see-through displays, in depicting virtual content inside the human body for surgical planning. Their inherent limitations result in inaccuracies in perceived object positioning. We examine how occlusion, specifically with opaque surfaces, affects perceived depth of virtual objects at arm's length working distances. A custom apparatus with a half-silvered mirror was developed, providing accurate depth cues excluding occlusion, differing from commercial displays. We carried out a study, contrasting our apparatus with a HoloLens 2, involving a depth estimation task under varied surface complexities and illuminations. In addition, we explored the effects of creating a virtual "hole" in the surface. Subjects' depth estimation accuracy and confidence were assessed. Results showed more depth estimation variation with HoloLens and significant depth error beneath complex occluding surfaces. However, creating a virtual hole significantly reduced depth errors and increased subjects' confidence, irrespective of accuracy enhancement. These findings have important implications for the design and use of mixed-reality technologies in surgical applications, and industrial applications such as using virtual content to guide maintenance or repair of components hidden beneath the opaque outer surface of equipment. A free copy of this paper and all supplemental materials are available at https://bit.ly/3YbkwjU.

Understanding Relationship between Length and Weight with Otolith Dimension of <i>Tenualosa ilisha</i> from Hooghly River (India)<sup>1</sup>

The Indian hilsa shad, Tenualosa ilisha (Hamilton, 1822), is a highly valued fish of the Indo Pacific region. This paper represents the length-weight relationships (LWR), condition factor (K), relative condition factor (Kn), and otolith dimension of hilsa, throughout the Hooghly River (West Bengal) from January to December 2020. The value of exponent “b” in the equation W = cLb was 2.6 for the species. It suggests the growth rate almost follows the cube law. Most of the population under study complied with the ideal b-value. Regression analysis indicated a high positive correlation between length and weight in the species (R2 = 0.76). The Kn shows their general well-being to be good in the river. The relationships between total fish weight and otolith biometry parameters such as long arm (L.A) length, short arm (S.A) length, L.A/S.A, and diameter (D) were examined. Linear regressions have represented fish weight-otolith biometry relationships. Regression analysis indicated a strong positive relationship between body weight and otolith length (R2 = 0.848), otolith diameter (R2 = 0.803), and short arm length of otolith (R2 = 0.678), but no relationship was found between L.A/S.A of otolith and fish weight. This strong relationship between fish weight and otolith length and diameter of T. ilisha, reflects that otolith length and diameter could become the best predictor of fish weight.

ТЕХНОЛОГИЧЕСКИЕ НЮАНСЫ ПРОМЫШЛЕННОГО УКРЫВНОГО ВИНОГРАДАРСТВА

On industrial covered for winter vineyards the reaction of experimental vine varieties to vari-ous agrotechnical techniques (vine training sys-tem, age and arm length), their influence on productivity indictors and crop quality in the environmental conditions of the Rostov region and the Chechen Republic is shown. The func-tional dependence of the parameters of agro-biotechnological features on the developed agrotechnical techniques has been established. The optimal values for vine and eye number, plant productivity indicators, crop quality, labor productivity and economic efficiency were ob-served when using the long-arm training we proposed with a different combination of struc-tural elements, the method of vine pruning and the load rate of bushes. To conform the re-quirements of industrial technologies two 150−200 cm long arms are formed in bush structure with 2−4 branches on each arm. The principal requirement in the method is the for-mation of strict Z-shaped bend at the base of the arms which ensures the bushes after releas-ing from trellis, their strict orientation along the row and high-quality mechanized winter cover-ing of bushes by vinehandlers. In spring, after opening the bushes, the fruit vines grow at a height of 70−120 cm. (on the first and second levels of tree-leveled trellis). Vine is pruned at the length of 6−12 eyes, the load is 80−90 thousand shoots per hectare, with a bush plant-ing scheme 3×1.5−2.0 m. Such parameters of agricultural practices increase the productivity of plantings by 20−25 % with high technologi-cal conditions, and a reduction in labor expend-itures costs by 15−20 man-days per hectare.

Generalized Mach Zehnder Interferometers Integrated on Si3N4 Waveguide Platform

We demonstrate 3 × 3 and 4 × 4 Generalized Mach Zehnder Interferometers (GMZI) integrated on the Si <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> waveguide platform and present their experimental performance as switching and variable power splitting modules. The GMZI structures have been theoretically modelled by means of a transfer matrix model, evaluating also the GMZI spectral response in the case of fabrication errors that may lead to variations in GMZI arm lengths, MMI phase shifts and MMI splitting ratios. Both 3 × 3 and 4 × 4 GMZI structures were fabricated as integrated Si <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> N <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">4</sub> -based circuits and were experimentally characterized with the experimental results being in close agreement with the theoretical predictions. They both reveal a resonant spectral behavior with an FSR of 1.9 nm and low average insertion losses per port that were measured to be 1 ± 0.2 and 2.4 ± 0.4 dB. The two GMZI structures were utilized as 1:3 and 1:4 switching elements, respectively, with average crosstalk levels being always greater than 10 dB for all possible input-output port combinations. Finally, their credentials to serve within linear optical circuit implementations were evaluated through their experimental characterization in variable power splitting applications, showing that the power level at a single output port can take any value between 0 and 100% of the input signal.

The Efficient Energy Collection of an Autoregulatory Driving Arm Harvester in a Breeze Environment.

Breezes are a common source of renewable energy in the natural world. However, effectively harnessing breeze energy is challenging with conventional wind generators. These generators have a relatively high start-up wind speed requirement due to their large and steady rotational inertia. This study puts forth the idea of an autoregulatory driving arm (ADA), utilizing a stretchable arm for every wind cup and an elastic thread to provide adjustable rotational inertia and a low start-up speed. The self-adjustable rotational inertia of the harvester is achieved through coordinated interaction between the centrifugal and elastic forces. As the wind speed varies, the arm length of the wind cup automatically adjusts, thereby altering the rotational inertia of the harvester. This self-adjustment mechanism allows the harvester to optimize its performance and adapt to different wind conditions. By implementing the suggested ADA harvester, a low start-up speed of 1 m/s is achieved due to the small rotational inertia in its idle state. With the escalation of wind speed, the amplified centrifugal force leads to the elongation of the driving arms. When compared to a comparable harvester with a constant driving arm (CDA), the ADA harvester can generate more power thanks to this stretching effect. Additionally, the ADA harvester can operate for a longer time than the CDA harvester even after the wind has stopped. This extended operation time enables the ADA harvester to serve as a renewable power source for sensors and other devices in natural breeze environments. By efficiently utilizing and storing energy, the ADA harvester ensures a continuous and reliable power supply in such settings.

Effect of power arm length combined with additional anterior torque on the axial orientation of the maxillary incisors during en-masse retraction: A finite element analysis

This study aimed to clarify the effect of power arm length combined with additional torque incorporated into the archwire on the controlled movement of the anterior teeth using the finite element method. An adult patient requiring medium anchorage after extraction of the maxillary first premolars was selected for this study. The power arms were placed between the lateral incisor and the canine at 3 levels: 3 mm, 6 mm, and 9 mm. A 150 g of retraction force was applied from each height of the anterior hook to the first molar tube, with 0°, 5°, and 10° of applied lingual root torque on the incisors. A 3-mm hook with 10° of applied torque, a 6-mm hook with 5° of applied torque, or a 9-mm hook with no extra torque constituted the best combinations targeted at controlling the inclination of incisors during retraction. Extrusion and distal tipping of the canine were observed. Moreover, mesial tipping and mesiopalatal rotation of the molar were unavoidable. Finally, intercanine and intermolar widths were decreased. Adding extra torque on the incisors or using high torque brackets is recommended for patients with maxillary first premolar extraction.