Unequal Length Research Articles

Springs regarded as hydraulic features and interpreted in the context of basin-scale groundwater flow

Springs are sources of freshwater supply. Furthermore, they can also deliver valuable insight into the hydrogeologic processes of a mountainous region, a natural conservation area or a remote study site with no wells. In order to assess the appearance, peculiarities, quality, stability, longevity and resilience of springs and related ecosystems, they need to be regarded in the context of basin-scale groundwater flow systems. The application of spring data evaluation on a basin scale was demonstrated via the carbonate system of Transdanubian Mts., Hungary. The readily measurable physical parameters of springs, the elevation of spring orifice, temperature and volumetric discharge rate provided reasonable classification and characterisation of springs and the related groundwater flow systems. Applying these parameters seemed prospective in a basin-scale understanding of flow systems in data-scarce regions, as monitoring discharge rate and water temperature are cost-effective, requiring no specific tools and analysing procedures. The combined cluster and discriminant analysis (CCDA) can handle uneven data distribution, unequal length and spacing of time series, data gaps, and consider the time-dependent variability of parameters. The optimal number of groups can be determined based on frequently sampled springs (or other entities). The less monitored springs (or other entities) can be classified using a similarity-based approach and linear discriminant analysis (LDA). Diagnosing the relation of springs to groundwater flow systems can advance sustainable water resources management, considering the ecological water needs maintaining various ecosystem services, therefore enhancing the resilience of springs and groundwater-dependent ecosystems.

Effect of Mechanical Loadings on Two Unequal Slanted Cracks Length in Bi-Materials Plate

Although a lot of crack problems in bi-materials plate were previously treated, few solutions are available under mechanical loadings, arbitrary crack lengths and material combinations. In this paper the dimensionless stress intensity factors (SIFs) of two slanted cracks in the upper plate of bi-materials are considered under mechanical loadings with varying the crack length and material combinations systematically. In order to calculate the dimensionless SIFs accurately, the hypersingular integral equations (HSIEs) was formulated by using the modified complex potentials (MCP) function. The details numerical results of the dimensionless SIFs are given in tabular form and graphical presentations. Comparisons with the existing exact solutions show that the numerical results in this paper have high accuracy. Our results are described with clarifying the effect of the mechanical loadings, bi-elastic constant ratio and element size of cracks on the dimensionless SIFs.

S2Snet: deep learning for low molecular weight RNA identification with nanopore.

Ribonucleic acid (RNA) is a pivotal nucleic acid that plays a crucial role in regulating many biological activities. Recently, one study utilized a machine learning algorithm to automatically classify RNA structural events generated by a Mycobacterium smegmatis porin A nanopore trap. Although it can achieve desirable classification results, compared with deep learning (DL) methods, this classic machine learning requires domain knowledge to manually extract features, which is sophisticated, labor-intensive and time-consuming. Meanwhile, the generated original RNA structural events are not strictly equal in length, which is incompatible with the input requirements of DL models. To alleviate this issue, we propose a sequence-to-sequence (S2S) module that transforms the unequal length sequence (UELS) to the equal length sequence. Furthermore, to automatically extract features from the RNA structural events, we propose a sequence-to-sequence neural network based on DL. In addition, we add an attention mechanism to capture vital information for classification, such as dwell time and blockage amplitude. Through quantitative and qualitative analysis, the experimental results have achieved about a 2% performance increase (accuracy) compared to the previous method. The proposed method can also be applied to other nanopore platforms, such as the famous Oxford nanopore. It is worth noting that the proposed method is not only aimed at pursuing state-of-the-art performance but also provides an overall idea to process nanopore data with UELS.

Main-chain side-chain combined liquid crystalline polymers bearing azobenzene and biphenyl-based mesogens – segregation of the mesogens within two distinct layers

ABSTRACT Two different mesogenic units, namely biphenyl and azobenzene, were installed centrally within the polymer backbone and pendant alkylene segments; the purpose was to examine if chain folding of the backbone occurs so as to segregate the azobenzene and biphenyl units in adjacent layers of a smectic-type ordering. Two sets of isomeric main-chain side-chain liquid crystalline polymers (MCSC-LCPs), namely SC-AzoCx-MC-BPCx and SC-BPCx-MC-AzoCx (x=6 or 10), were synthesised; the former series has biphenyl in the backbone and azobenzene in the side-chain, while their locations are switched in the latter. It was observed that all four polymers were semicrystalline at room temperature and exhibited a smectic mesophase upon melting. DSC and X-ray scattering studies revealed that switching the locations of the azobenzene and biphenyls had little effect on; the phase transition temperatures and smectic layer spacings. A second series, namely SC-AzoCx-MC-BPCy and SC-BPCx-MC-AzoCy, where the length of alkylene spacers in the side-chain (Cx) and backbone (Cy) is different, was also studied; this was done to examine the influence of unequal alkylene segment lengths on the mesophase structure and interlayer spacing, and importantly, whether the zigzag folding-induced formation of a layered structure is retained, despite their unsymmetrical nature.

Re-description and molecular phylogeny of the free-swimming peritrichs Hastatella radians Erlanger, 1890 and H. aesculacantha Jarocki & Jakubowska, 1927 (Ciliophora, Peritrichia) from China

The present work investigated Hastatella radians Erlanger, 1890 (type species), and H. aesculacantha Jarocki & Jakubowska, 1927, isolated from Chongming Island, Shanghai, China, based on light microscopy observations of live individuals, silver staining and molecular phylogeny methods. Hastatella radians is characterized by its size (about 30–75 μm long, 25–70 μm wide), two girdles of ectoplasmic processes, infundibular polykinety 3 (P3) composed of two rows of unequal length and terminating beyond adstomal end of P2, 8–22 transverse silverlines between peristome and trochal band, and 5–9 between trochal band and scopula. The infraciliature of H. aesculacantha is described for the first time, and we improved its diagnosis: cell size about 25–52 × 20–41 μm in vivo; four girdles of ectoplasmic processes; P3 two-rowed, outer row much shorter than inner one; 5–7 silverlines between peristome and trochal band and four or five between trochal band and scopula. Phylogenetic analyses based on SSU rDNA sequences revealed that Hastatella is monophyletic and has a close relationship to Astylozoon enriquesi.

Przemiany estetyki

Metamorphosis of Aesthetics Many aesthetic lecturers feel that the subject of their lectures is not so much aesthetics as the history of aesthetics, the aesthetic views of Plato and Aristotle, Kant and Hegel, Hume and Burke, British philosophers of taste and German romantics. Does this mean that aesthetics is nourished by its own past, nourished by reinterpretations of its classics, defends concepts and categories that no longer inspire anyone? Don’t they open up new cognitive perspectives? Does this mean that aesthetics is dead today, like Latin or Sanskrit, and that its vision of art and beauty is outdated, out of date and completely useless? Stefan Morawski in the introduction to the anthology Twilight of Aesthetics – Alleged or Authentic? he wrote that he did not know the history of aesthetic thought that would begin in the eighteenth century with Baumgarten. Today we can meet with such an approach more and more often. Many authors assume that in the second half of the 18th century, modern aesthetics was born as a science of senses, how our higher (sight, hearing) and lower senses (taste, smell, touch) contribute to our knowledge of the world. In the introduction to the anthology cited here, Stefan Morawski divides the history of aesthetics into four periods of unequal length. The Morawski diagram seems to be a convenient starting point for defining the changing object of aesthetics. The first of the periods distinguished by Morawski is the longest one, lasting from Ancient Greece to Enlightenment, can be called the history of aesthetic thought, the second is philosophical aesthetics, the third is a time of emancipation and institutionalization of aesthetics as autonomous discipline, and the fourth period leads beyond the limits of classical aesthetics.

Sampling rate-corrected analysis of irregularly sampled time series.

The analysis of irregularly sampled time series remains a challenging task requiring methods that account for continuous and abrupt changes of sampling resolution without introducing additional biases. The edit distance is an effective metric to quantitatively compare time series segments of unequal length by computing the cost of transforming one segment into the other. We show that transformation costs generally exhibit a nontrivial relationship with local sampling rate. If the sampling resolution undergoes strong variations, this effect impedes unbiased comparison between different time episodes. We study the impact of this effect on recurrence quantification analysis, a framework that is well suited for identifying regime shifts in nonlinear time series. A constrained randomization approach is put forward to correct for the biased recurrence quantification measures. This strategy involves the generation of a type of time series and time axis surrogates which we call sampling-rate-constrained (SRC) surrogates. We demonstrate the effectiveness of the proposed approach with a synthetic example and an irregularly sampled speleothem proxy record from Niue island in the central tropical Pacific. Application of the proposed correction scheme identifies a spurious transition that is solely imposed by an abrupt shift in sampling rate and uncovers periods of reduced seasonal rainfall predictability associated with enhanced El Niño-Southern Oscillation and tropical cyclone activity.

U-shape core-offset fiber sensor with submicrostrain resolution over a 35 millistrain range.

Large strain with submicro resolution is essential for steel structural monitoring; however, the fiber base sensors are limited by the glass extension to be less than 1%. Here, we propose a U-shape core-offset fiber sensor including four fiber segments to realize a large strain sensor. Four fiber segments with slight length differences in between are core-offset fused together to achieve U-shape spring-like microstructure fiber for large transverse bending radius. The reflected high-order modes at three silica/air interfaces interfere to give a broad spectrum due to unequal segment length, which enables continuous strain detection over 35 mɛ. The air and glass hybrid structure of the device enables the large bending, and hence compression and tension measurement can be achieved simultaneously. The strain sensitivity is up to 20.75 pm/µɛ with the strain accuracy of 0.5 µɛ. This novel, to the best of our knowledge, core-offset fiber has high strain sensitivity and large strain range for compression and tension strain measurement. Furthermore, the proposed strain sensor can be fabricated easily for practical applications where large strain with high strain accuracy is needed.

Leftward Spatial Bias in Dialyzed Patients With End-Stage Renal Disease: A Sign of Right Hemispheric Attentional Activation or Impaired Left-Sided Disengagement?

In the horizontal line bisection task, patients with end-stage renal disease (ESRD) treated with dialysis typically have an increase in the normal leftward attentional bias. It is not clear, however, whether this increased bias is related to an increase of attention toward left hemispace or impaired disengagement from left-sided stimuli. Non-demented patients with ESRD who were being treated with dialysis and demographically matched healthy controls attempted to bisect series of horizontal lines composed of two segments of unequal length and width, with the longer segment placed to the right or left. To test for the presence of a global spatial attentional bias, participants attempted to find the middle of the whole line. To test for focal attentional engagement and attentional disengagement, participants were asked to bisect only the longer segment of these compound lines. For the global condition, both patients and healthy controls were biased toward the longer segment and more so to the left. In the focal condition, when the longer segment was on the right side, both groups deviated their bisections toward the shorter segment. However, when in the focal condition the longer segment was on the left healthy controls deviated their bisection significantly more rightwards than did the patients, whereas with the longer segment on the right, the patients and healthy controls did not differ in their bias. These results suggest that the previously recognized dysfunction of the right fronto-subcortical attentional network in dialyzed patients might account for the results of the current study.

Bandwidth Enhancement and Size Reduction of a Low-Profile Polarization-Reconfigurable Antenna by Utilizing Multiple Resonances

A new design method to significantly expand the axial ratio (AR) bandwidth of a single-fed, low-profile circularly polarized (CP) antenna without relying on any complex feed network or occupying a large transverse dimension is presented. First, four small patches arranged in chessboard pattern are utilized as the main radiator, and meanwhile, a cross slot with unequal slot lengths is adopted to excite triple sequentially orthogonal modes, aiming to attain two CP modes (AR <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> and AR <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> ). Second, in order to further considerably enhance the AR bandwidth and concurrently reduce the overall size, the feeding cross-slot resonance is favorably excited and effectively coupled by the chessboard patches to produce a new slotline-based CP mode (AR <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> ) located before AR <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> . Finally, an I-shaped top-loaded monopole fence, as a new degree of design freedom, is employed to collaboratively regulate these multiple resonances to form a wide AR bandwidth covering AR <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">1</sub> , AR <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> , and AR <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">3</sub> . Results show that, on the premise of keeping the inherent compact-size and low-profile advantages of microstrip antenna, the 3 dB AR bandwidth is remarkably enhanced up to 30.1% by the combination of the three CP modes. Based on the design method, a wideband polarization-reconfigurable antenna with switchable linear polarization (LP), left-handed circular polarization (LHCP), and right-handed circular polarization (RHCP) states is further designed and experimentally validated. The measured results demonstrate that, with quite compact transverse size ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.16\lambda _{0}^{2}$ </tex-math></inline-formula> ) and low profile ( <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$0.04\lambda _{0}$ </tex-math></inline-formula> ), a wide overlapped bandwidth (27.6%) of the polarization-reconfigurable antenna is successfully accomplished.

Interrelation between grid systems and star polygons of muqarnas ground projection plans

Many muqarnas ground projection plans contain stars with unequal edge lengths in their compositions. In this study, the geometric reasons behind the unequality of star edge lengths in muqarnas ground projection plans have been searched. The main gates with complex-looking muqarnas belonging to the period of Suleiman the Magnificent (Kanuni Sultan Suleyman), designed by Architect Sinan in Istanbul, have been selected to examine. From the data obtained by 3D laser scanning and from the verification made, it has been confirmed that there are stars with unequal edge lengths in these muqarnas plans. From the geometrical examinations made according to the shape grammar theory, it was concluded that the muqarnas plans were created using spider-web grid and square grid layouts. It was also concluded that these grid types cause some of the star edge lengths to be unequal.

New data on Henneguya postexilis Minchew, 1977, a parasite of channel catfish Ictalurus punctatus, with notes on resolution of molecular markers for myxozoan phylogeny.

Previous morphological and histological data are supplemented with molecular and ultrastructural data for a Henneguya sp. isolated from farm-raised channel catfish Ictalurus punctatus in Mississippi, USA. Myxospores were cryptic, encapsulated within a thin layer of epithelium in the gill lamellae with spore measurements consistent with the original description of Henneguya postexilis Minchew, 1977. Myxospores were 42.7-49.1 µm in total length with spore bodies 12.1-17.2 × 3.6-4.8 × 2.9-3 µm. Polar capsules were of unequal length, with the longer capsule being 4.4-6.7 × 1.1-1.6 µm and the shorter capsule being 4.4-6.4 × 1.1-1.6 µm. Polar tubules had 6-8 turns. Caudal processes were 25.7-38.1 µm in length. Spores were encapsulated in a thin layer of epithelium in the gill lamellae. Molecular data from the most commonly used markers for myxozoan identification and phylogeny, partial 18S small subunit ribosomal gene (SSU), partial 28S large subunit ribosomal gene (LSU), and elongation factor 2 (EF2) were generated for H. postexilis. Additionally, novel data for LSU and EF2 were generated for archived myxozoan specimens from farm-raised catfish (H. mississippiensis, H. ictaluri, H. exilis, H. adiposa, H. sutherlandi, H. bulbosus, Unicauda fimbrethilae), as well as archived specimens from wild fish (H. laseeae [from Pylodictis olivaris], Hennegoides flockae [from Aphredoderus sayanus], Myxobolus cloutmani [from Cycleptus elongatus]. These include the first EF2 sequence data for the genera Hennegoides and Unicauda. Phylogenetic analyses using these data placed H. postexilis in well supported clades with other ictalurid-infecting Henneguya species. Phylogenetic signal assessments on these analyses suggest that while SSU provided the greatest phylogenetic signal, LSU yielded comparable signal, supporting previous work implying this region may be underutilised in reconstructing myxobolid phylogenies.

Reconstruction of Optical Image Time Series With Unequal Lengths SAR Based on Improved Sequence–Sequence Model

Optical remote sensing time series are optimal for understanding and monitoring biochemical changes of key phenological parameters, which is essential for the assessment of vegetation health. However, due to cloud contamination, optical images often lack several days’ to months’ worth of information. Therefore, reconstructing optical time series based on the synthetic aperture radar (SAR) is necessary, which has the advantage of the production of continuous images under all weather conditions. In this study, an improved sequence-to-sequence (Seq2Seq) model was proposed, which integrated teacher forcing (TF) with the attention mechanism to handle input and output time series with unequal lengths. The proposed model could be used to reconstruct optical full-band time series using SAR time series data and reduce sample requirements based on the modification of the loss calculation method. To explore the spatiotemporal scalability of the proposed model, the test samples were divided into three categories: same time but different spatial domain, different time but same spatial domain, and both different temporal and spatial domains. The major findings can be summarized as follows: 1) 72.7% of the generated Landsat 8 sequence values had an absolute error of less than 0.05; 2) The mean absolute error of all bands was less than 0.0812; 3) The mean squared errors of all samples were lower than 0.015 regardless of the type of the test sample; and 4) TF was introduced to the model to improve the accuracy of the generated Landsat 8 sequence, yielding an increase of more than 5.97%. We concluded that the proposed model had good robustness both temporally and spatially. It performed well in the reconstruction of optical image time series, provided a basis for the use of time series pairs with unequal lengths, and can be applied to cloud removal and vegetation index reconstruction.

О таксонах рода × Trisetokoeleria (Poaceae) в российской Арктике

An amplified description of the Siberian Arctic species × Trisetokoeleria taimyrica Tzvelev is compiled, based on the study and measurements of about 100 reproductive shoots (10 herbarium sheets) stored in the Herbarium of the Komarov Botanical Institute RAS (LE), including the neotype designated by the authors and 4 authentic herbarium specimens identified by N. N. Tzvelev. The main distinctive characters of the three species of the genus × Trisetokoeleria are given in the table, taking into account additional data on × T. taimyrica. The difficulty of recognizing the × Trisetokoeleria species in nature (the use of optics is necessary) is complicated by a weak difference in key features, primarily between T. gorodkowii (Roshev.) Tzvelev and T. taimyrica. The third species, namely T. jurtzevii Prob., clearly differs from the other two by pubescent (hairy) inflorescence branchlets and longer awns. × T. taimyrica differs from × T. gorodkowii by narrower, few-flowered panicles, glumes of slightly (vs. strongly) unequal length, and acuminate (vs. obtuse) lemma tips, and from × T. jurtzevii by glabrous stem, panicle branchlets and lemmas, as well as by shorter awns and narrower few-flowered panicles. Its differences from postulated parent species are as follows: from Koeleria asiatica Pers. — a short straight awn extending below the lemma tip (vs. extending from the very tip of the lemma, that is sometimes observed in K. asiatica), and glabrous stems and panicle branchlets; from Trisetum agrostideum (Laest.) Fr.) — a very short, straight awn extending slightly below the lemma tip (vs. twice articulated and extending slightly above ½ or at upper ⅓ of the lemma), as well as spike-like panicles. A map of the localities of the three × Trisetokoeleria species is compiled.

Induced Membrane Technique for Reconstruction of a 25 cm Humerus Diaphyseal Defect Secondary to Chronic Osteomyelitis in an Adolescent

The surgical treatment of long bone defects in septic environments remains a challenge for any orthopedic surgeon. The two-stage reconstruction technique described by Masquelet AC is a better alternative in our regions where expertise in microsurgical techniques is rare. We report our first experience with this technique through the reconstruction of the humeral diaphyseal bone defect. We presented a 12-year-old boy diagnosed with chronic osteomyelitis of the left humerus with sequestrum, a pathologic fracture with overly joint involvement. The first stage consisted of a sequestrectomy removing the entire humerus shaft (25 cm) with conservation of the humerus paddle followed by the implantation of cement spacer into the bone defect and stabilization with 2 Kirschner wires (22/10th) and a thoraco-brachial cast. Eleven months later, we performed a cancellous autograft associated with a free non-vascularised fibula graft (12 cm). The bone corticalisation was obtained after 11 months. At the 43-month follow-up, despite joint stiffness and unequal length of brachial segments, the patient and his parents were satisfied.

Low-Profile and Wideband Circularly Polarized Magneto-Electric Dipole Antenna Excited by a Cross Slot

In this article, we present the design of a low-profile circularly polarized (CP) magneto-electric (ME) dipole antenna with enhanced CP bandwidth properties. The ME dipole antenna is excited by a simple microstrip line aperture-coupled feeding structure. The coupling aperture is composed of two crossed slots of unequal lengths to realize CP operation. Four identical inverted L-shaped parasitic elements, each consisting of a horizontal patch and a vertical metallic plate, are vertically positioned around the ME dipole. It was found that such parasitic elements can remarkably improve the 3 dB axial ratio (AR) bandwidth while retaining the wide impedance bandwidth. A prototype with a low profile of only 0.134λL (λL is the wavelength in free space at the lowest operating frequency) is fabricated and tested to verify the proposed design. The experimental results show that the prototype has an overlapping impedance bandwidth (|S11| ≤ –10 dB) and a 3 dB AR bandwidth of 3.16–5.36 GHz (51.35%) with a maximum broadside left-handed CP gain of 9.75 dBic. Additionally, nearly identical radiation patterns on two principle cutting planes are obtained over the operating band.

Beam–Unequal Length Piles–Soil Coupled Vibrating System Considering Pile–Soil–Pile Interaction

Abstract In recent years, the π-shape structure, that is, two pile shafts supporting a reinforced concrete beam and its superstructure, is increasingly used for bridge foundations. Considering the ...

A Novel Feature Representation for Prediction of Global Horizontal Irradiance Using a Bidirectional Model

Complex weather conditions—in particular clouds—leads to uncertainty in photovoltaic (PV) systems, which makes solar energy prediction very difficult. Currently, in the renewable energy domain, deep-learning-based sequence models have reported better results compared to state-of-the-art machine-learning models. There are quite a few choices of deep-learning architectures, among which Bidirectional Gated Recurrent Unit (BGRU) has apparently not been used earlier in the solar energy domain. In this paper, BGRU was used with a new augmented and bidirectional feature representation. The used BGRU network is more generalized as it can handle unequal lengths of forward and backward context. The proposed model produced 59.21%, 37.47%, and 76.80% better prediction accuracy compared to traditional sequence-based, bidirectional models, and some of the established states-of-the-art models. The testbed considered for evaluation of the model is far more comprehensive and reliable considering the variability in the climatic zones and seasons, as compared to some of the recent studies in India.

Dual-band (28/38 GHz) Yagi–Uda Antenna with Corrugated Radiator and Triangular Reflectors for 5G Mobile Phones

A novel printed design of a Yagi-Uda antenna is introduced for dual-band operation at 28/38 GHz. A corrugated strip dipole with a capacitively end-coupled extension strip is employed as the driven element. The proposed antenna has two triangular-shape reflectors and one director. The driven dipole is fed through a coaxial feed line constructed as three unequal length transition strips. A four-port MIMO antenna system constructed using the proposed Yagi-Uda is suggested for mobile phones. CST® simulator is used to study the effect of the different design parameters on the antenna gain and the operating bands. Numerical and experimental investigations are achieved to assess the performance of both the single-element antenna and the four-port MIMO antenna system. It is shown that the simulation results agree with the experimental measurements and both show good performance of the single antenna as well as the MIMO antenna system. The bandwidths achieved around 28 GHz and 38 GHz are about 4G Hz and 1.4 GHz, respectively. The gain of the antenna is about 9 and 10 dB at 28 and 38 GHz, respectively. The four antenna configuration shows radiation pattern diversity required for MIMO system. The envelope correlation coefficient (ECC) and the diversity gain (DG) are calculated and the results show that the proposed MIMO antenna system is suitable for the forthcoming 5G mobile communications.

Waveguide for air-coupled ultrasonic phased-arrays with propagation time compensation and plug-in assembly.

Waveguides allow grating lobe free beamforming for air-coupled ultrasonic phased-arrays by reducing the effective inter-element spacing to half wavelength. Since the sound waves propagate through the waveguide ducts, additional time delays are introduced. In this work, we present analytical, numerical, and experimental methods to estimate these time delays. Afterwards, two different waveguides are compared. The first one consists of equal-length ducts, requiring a time-consuming assembly process of the ultrasonic phased-array. In contrast, the second waveguide consists of Bézier-shaped ducts of unequal lengths but a planar input port allowing fast assembly. The analytical model is based on the geometric lengths of the waveguide ducts. The numerical model relies on a transient finite element analysis. All simulations are validated in an anechoic chamber using a calibrated microphone. The analytical (7.6% deviation) and numerical (3.2% deviation) propagation time models are in good agreement with the measurements. By using the analyzed propagation times for the compensation of the unequal waveguide duct lengths, we restored the beamforming capability without significant sound pressure level (SPL) loss. This work shows the possibility of reduced transducer assembly time for waveguided air-coupled phased-arrays without a reduced SPL.