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The interaction between the double-track shield tunnel and the integrated pipe gallery is complex, and there is still a lack of systematic research. Based on the numerical simulation of the Xi’an case, this paper studies the influence of the construction of the integrated pipe gallery on the deformation characteristics of the existing double-line subway tunnels with different buried depths and clear distances and finds the safe buried depth and clear distance of the tunnel. The results indicated that, in the loess area, the maximum deformation of the existing subway has a linear and inverse relationship with the buried depth and spacing, respectively. Increasing the buried depth can reduce the impact of the upper construction disturbance more than increasing the clear distance ratio. Moreove, under the design conditions of constructing a utility tunnel by the open-cut method, when the buried depth of the tunnel is 4.5 D and the spacing is greater than 4.5 D, or the buried depth is 5.0 D and the spacing is greater than 2.5 D, the combination of subway tunnels can meet the deformation control standards.

Intertrochanteric femur fractures (ITFF) are frequently fixed with proximal femoral nailing (PFN), and a common cause of fixation failure is cut-out of the lag screws. In the literature, many factors have been defined to determine the failure risk, including the tip–apex distance (TAD), calcar-referenced tip–apex distance (CalTAD), the Cleveland zone and Parker's ratio. In this study, a novel technique is described which favors infero-posterior placement of the lag screw and predicts failure risk for PFN. The purpose of this study was to evaluate the tip–neck distance ratio as a factor for the prediction of cut-out after PFN of ITFF. A retrospective evaluation was made of the data of 125 patients applied with PFN for ITFF between October 2016 and September 2019. The occurrence of mechanical complications was analyzed in relation to age, gender, fracture side, American Society of Anaesthesiologists classification, fracture classification, reduction quality, bone quality, Cleveland zone, Parker’s ratio, TAD, CalTAD and the TNDR. A total of 125 patients, including 16 with mechanical complications, were suitable for full analysis. In the univariate analysis, reduction quality (p = 0.003), the TAD (p = 0.048) and the TNDR (p = 0.030) were statistically associated with mechanical complications (p

In Li et al. (J Aust Math Soc 97:383–390, 2014), the authors discussed two classes of mappings in Banach spaces, which are $$\varphi $$ -quasiisometric mappings in the distance ratio metric (briefly, $$\varphi $$ -DRQI mappings) and fully $$\varphi $$ -quasiisometric mappings in the distance ratio metric (briefly, $$\varphi $$ -FDRQI mappings), where $$\varphi :$$ $$[0,\infty )\rightarrow [0,\infty )$$ denotes a quasiisometric control function. In this paper, we continue this discussion by introducing a new class of mappings, that is, $$\varphi $$ -PDRQI mappings. The purpose of this paper is twofold. Let f be a homeomorphism between two proper domains in a Banach space. First, we prove that f being $$\varphi $$ -PDRQI is equivalent to f being $$\varphi $$ -FDRQI. Then, as an application of the obtained equivalent relation, we show that f being $$\varphi $$ -DRQI, f being $$\varphi $$ -PDRQI and f being $$\varphi $$ -FDRQI are equivalent to each other when the quasiisometric control functions have the form $$\varphi (t)=Mt$$ .

BACKGROUND A few patients of apparently normal appearance unexpectedly present with great difficulties during intubation which may lead to potentially serious consequences. Thus, we worked on this area with the aim to determine the ability to predict difficult visualisation of larynx using the following preoperative airway predictors: MMC (Modified Mallampati Classification), RHSMD (Ratio of Height to Sternomental Distance), RHTMD (Ratio of Height to Thyromental) and HMDR (Hyomental Distance Ratio) and comparison of these with WRSS (Wilson Risk Sum Score), in isolation and in combination. METHODS A double-blind, prospective study was carried out on 300, ASA grade I or II patients posted for elective surgery in supine position under general anaesthesia. Different parameters were recorded in pre-op period and Cormack-Lehane grading and difficulty of intubation was recorded at the time of intubation. Chi Square test and receiver operating curve were used to assess the association of all the airway tests and various combinations with CL grading. Cohen’s kappa was calculated to determine the strength of agreement between laryngoscopy grade and various tests in isolation and combinations. RESULTS In our study, highest strength of agreement was found with WRSS of 0.925 (0.873 - 0.976) and only a fair agreement was seen with HMDR (κ = 0.319). RHSMD and combination of RHSMD + MMC showed good strength with kappa of 0.638 and 0.634 respectively. CONCLUSIONS No single test or group of tests was able to predict all cases of difficult laryngoscopy at the preoperative airway assessment. Wilson Risk Sum Score was found to be the best predictor of difficult laryngoscopy when compared to MMC, RHTMD, RHSMD and HMDR in isolation and any possible combination. KEYWORDS Difficult Laryngoscopy, Difficult Intubation, Wilson Risk Sum Score, Airway, RHSMD, RHTMD

Farsi font detection is considered as the first stage in the Farsi optical character recognition (FOCR) of scanned printed texts. To this aim, this paper proposes an improved version of the speeded-up robust features (SURF) algorithm, as the feature detector in the font recognition process. The SURF algorithm suffers from creation of several redundant features during the detection phase. Thus, the presented version employs the redundant keypoint elimination method (RKEM) to enhance the matching performance of the SURF by reducing unnecessary keypoints. Although the performance of the RKEM is acceptable in this task, it exploits a fixed experimental threshold value which has a detrimental impact on the results. In this paper, an Adaptive RKEM is proposed for the SURF algorithm which considers image type and distortion, when adjusting the threshold value. Then, this improved version is applied to recognize Farsi fonts in texts. To do this, the proposed Adaptive RKEM-SURF detects the keypoints and then SURF is used as the descriptor for the features. Finally, the matching process is done using the nearest neighbor distance ratio. The proposed approach is compared with recently published algorithms for FOCR to confirm its superiority. This method has the capability to be generalized to other languages such as Arabic and English.

Based on the numerical simulation, the deformation characteristics of incremental sheet punching (ISP) of perforated sheet with circular holes was studied. Combined with the experimental results, the feasibility of using the normalized Cockroft-Latham ductile fracture criteria to predict fracture of perforated sheet during the ISP process was verified. On the basis of above, the influence of the geometric parameters of perforated sheet on the formability was studied. The main conclusions are the major strain is much greater than the minor strain at the interval of holes on the side wall of the perforated sheet; the thickness at the short-axis edge of the hole is smaller than that at the long-axis edge obviously; and the maximum value of major strain of perforated plate decreases with the increase of straight diameter center distance ratio. It is feasible to predict fracture of perforated sheet during the ISP process by numerical simulation with normalized Cockroft-Latham ductile fracture criteria.

In this paper, two methods of zoom motion estimation for color and depth videos by using depth information are proposed. Color and depth videos are independently estimated for zoom motion. Zoom for color video is scaled by spatial domain, and depth video is scaled by both spatial and depth domains. For color video, instead of existing methods of zoom motion estimation that apply all of possible zoom ratios for a current block, the zoom ratio of the proposed method is determined as the ratio of the average depth values of the current and reference blocks. Then, the reference block is resized by multiplying the zoom ratio and the reference block is mapped to the current block. For depth video, the reference block is first scaled in the spatial direction by the same methodology used for color video and then scaled by a distance ratio from a camera to the objects. Compared to the conventional motion estimation method, the proposed method reduces MSE by up to about 30% for the color video and up to about 85% for the depth video.

A research program was undertaken to study the shear-lag phenomenon for slotted HSS tension members having gusset plates welded at the ends, a commonly employed detail in braced frame construction. The purpose of this study was to establish whether the shear-lag reduction factor indeed involves only the weld length to weld distance ratio, Lw/w or if other parameters also influence connection strength and behaviour. These include the aspect ratio bo/do and the slenderness ratio bo/to.

In this research carried out to analyse the tensile strength of serially pinned bolted joints in composite plates which is made of pure E-glass and E-glass blended with fly ash. Fabrication of both plates in hand lay-up method by using vinyl ester, methyl ethyl ketone per-oxide and cobalt-2-naptanate. Analyse the tensile strength of plates with one, two, three and four serially pinned bolted joints done by experimentally. Experimental studies has been done by consider the following parameters are edge distance to-hole diameter ratio (E/D), plate width-to-hole diameter (W/D) Hole-to-hole distance ratio (K/D) as per ASTM standards.

Continuous change in the energy sector towards more sustainable solutions has raised the importance of managers' abilities to interpret changes in their environments and translate those perspectives into strategic choices. This study examines managerial interpretation on changing business environment opening the relationship of cognitive diversity, board composition, and performance differences across the cleantech firms. The authors' empirical study employs both indirect and direct cognitive measures for analysis of cognitive maps collected through surveys from the cleantech firms. The study utilizes the hybrid cognitive mapping technique with distance ratio to investigate cognitive diversity and bridges it with the firms' performance. The study also advances and operationalizes the distance ratio as a measure for the analysis of cognitive maps to utilize more information available in the maps. The results indicate that the managerial characteristics showing firm-level economic expertise creates high-level cognitive diversity and high financial volatility in performance among the cleantech firms.

In this paper, we introduce a class of mappings related to the distance ratio metric and study its connection to the freely quasiconformal mapping in Banach spaces. Moreover, we investigate the invariance of Gromov hyperbolic, natural and uniform domains under this class of mappings.

The discrete element method (DEM) has been widely used as a modelling tool to investigate soil-tool interactions. Soil particle size has an important effect on soil disturbance behaviours and cutting forces in discrete element models. In this study, discrete element models were developed using the EDEM software and evaluated using laboratory tests to investigate the effect of varying modelled particle radii (ranging from 3 to 19 mm) on soil-subsoiler interactions in the models. Soil disturbance characteristics (soil rupture distance ratio, height of accumulated soil, soil disturbance area, soil density change rate, and fragmentation index), solution time of the computer, and soil cutting forces (draft and vertical) were measured. Based on the ANOVA outputs, all these variables were significantly affected by the treatments at p

Micropiles can act as structural support for a new foundation and sustainable solution for existing foundations with advantages such as high load-carrying capacity and use in in situ conditions. Installing micropiles around the footing at some distance from the footing edge could turn out to be extremely helpful for existing distressed foundations where improvement is needed. An experimental investigation is carried out on a laboratory model square footing in the ongoing study, placed on sand, with micropiles driven around the footing. A parametric study focusing on the effect of the slenderness ratio of the micropiles, the state of sand beds, the micropile spacing ratio (S/b), and the micropile edge distance ratio (ED/d) are analyzed. The results demonstrate that the micropiles can appreciably improve the footing’s settlement characteristics and load-bearing capacity when placed around it. The load-carrying capacity shows some appreciable increase by increasing the slenderness ratio of micropiles, but increasing the slenderness ratio beyond 20 is insignificant. For unreinforced footing, a denser form of sand was found more advantageous in terms of bearing capacity, while as for reinforced footing, micropiles provided maximum improvement for medium-density sand. The improvement in bearing capacity is approximately 22.2% when the spacing ratio is reduced from 0.5 to 0.3. Also, for an edge distance ratio of 3, the improvement in the bearing capacity ratio is 76% higher than that of unreinforced footing. Multivariate linear regression showed a strong correlation between the experimental and predicted bearing capacity ratio.

Case Reports

Particle-size distribution (PSD) is a key parameter affecting soil dynamic attributes and cutting forces of tillage tools in the discrete element model in accordance with our preliminary simulations. To accurately determine PSD, significance and mechanism for the effect of PSD under different nominal radii were investigated using the discrete element method (DEM) and validated using the laboratory soil-bin results. Soil disturbance characteristics (soil rupture distance ratio, height of accumulated soil, soil density change rate) and cutting forces (draft and vertical) under different treatments were predicted and measured respectively. The ANOVA outputs showed that PSD significantly affected draft and vertical forces (p

Contour compression plays critical role in image processing applications. In this work we introduce a new version of Segments Distances Ratios (SDR) approach for contour approximation. At the beginning, the contour is extracted by an approach called single step parallel contour extraction (SSPCE). The main benefit of the modified version is that can gives more quality compared to the previous one by about 10 and 4 decibels, with compression ratio equals to 60% and 90% for single and multi-contours respectively. However the performed time almost the same for both algorithms. Finally, the discussion of the efficiency and the performance for the analyzed method is introduced.

In this paper, we prove that the inversions in metric spaces are coarsely bilipschitz continuous with respect to distance ratio metric.

Genotyping mistakes represent a challenge in parental assignment where even small errors can lead to significant amounts of unassigned siblings. Different parental assignment algorithms have been designed to approach this problem. The Exclusion method is the most applied for its reliability and biological meaning. However, the resolving power of this method is the lowest for data containing genotyping errors. We introduce a new distance-based approach which we coin as Distance-Based Exclusion (DBE). The DBE method calculates the distance between the offspring haplotype and haplotype of each of the potential fathers. The father with the lowest distance is then assigned as candidate father according to a distance ratio (α). We have tested the Exclusion and DBE methods using a real dataset of 1230 offsprings subdivided into families of 25 individuals. Each family had six potential fathers and one known mother. Compared with the Exclusion method, the DBE method is able to solve 4.7% more individuals (64.4% Exclusion vs 69.1% DBE) using the most restrictive α tested without errors. DBE method can also be used together with the Exclusion method for error calculation and to further solve unassigned individuals. Using a two-step approach, we were able to assign 98.1% of the offsprings with a total predicted error of 4.7%. Considering the results obtained, we propose the use of the DBE method in combination with the Exclusion method for parental assignment.

Previous studies examined training/match ratios (TMr) to determine the training load relative to the match load, but the influence of the relative training load (RTL) on success in soccer is still unknown. Therefore, this study aimed to investigate the possible influence of RTL on final match outcome in soccer (win, draw, and loss). Running performances (RP) of soccer players (n = 21) in the Croatian highest national soccer competition were analyzed during the season 2020–2021. Data were measured by the global positioning system in 14 official matches and 67 training sessions. RTL was assessed by TMr, which were calculated as the ratio of RP during training and match in the same week, evaluating the following measures: TDr (total distance ratio), LIDr (low-intensity distance ratio), RDr (running distance ratio), HIDr (high-intensity distance ratio), ACCr (total accelerations ratio), DECr (total decelerations ratio), HI-ACCr (high-intensity accelerations ratio), HI-DECr (high-intensity decelerations ratio). All TMr were examined separately for each training session within in-season microcycles (categorized as days before the match day, i.e., MD minus). Spearman correlations were used to identify association between match outcome and TMr. The results indicated negative associations between match outcome and TDr, LIDr, ACCr and DECr on MD-1 and MD-2). In contrast, positive associations were evidenced between match outcome, and HIDr on MD-3 and TDr, LIDr, ACCr and DECr on MD-5 (p &lt, 0.05, all moderate correlations). These findings demonstrate that final match outcome in soccer was associated with greater RTL of (i) high-intensity running three days before the match, (ii) total and low-intensity running, accelerations and decelerations five days before the match, and (iii) lower RTL of total and low-intensity running, accelerations and decelerations one and two days before the match.

In this work, the average symbol error rate (ASER) of rectangular quadrature amplitude modulation (RQAM) technique has been investigated under Rayleigh fading channels, considering exponential correlation among the input antennas of a maximal ratio combining (MRC) diversity reception. Exponential correlation is noticed by the antennas placed in a linear arrangement at the receiver. The response of the ASER for various levels of diversity order, correlation coefficient as well as the quadrature to in-phase decision distance ratio has been observed.

We construct from first principles a general relativistic approach to study Schwarzschild black hole (BH) rotation curves and estimate the mass-to-distance ratio of the active galactic nucleus of NGC 4258 in terms of astrophysical observable quantities. The presented method allows one to clearly distinguish and quantify the general and special relativistic contributions to the total redshift expression. The total relativistic redshift/blueshift comprises three components: the gravitational redshift due to the spacetime curvature generated by the mass of the BH in its vicinity, the kinematic shift, originated by the photons' local Doppler effect, and the redshift due to a special relativistic boost that describes the motion of a galaxy from a distant observer. We apply our method to the largest data set of highly redshifted water megamaser measurements on the accretion disk of the NGC 4258 active galaxy and use this general relativistic method to estimate its BH mass-to-distance ratio: M/D = (0.5326 +/- 0.00022) x 10^7 solar masses/Mpc., 8 pages, 4 figures, 1 table

Noise, as undesired sound, severely affects the quality of human life. Currently, active noise control method has demonstrated its capability in low-frequency noise cancellation and the advance in saving money and reducing weight and volume of related materials used in the passive noise control technology. The widespread configuration for active noise control technology is finite impulse response filter with filtered-x least mean squares (FxLMS) algorithm. However, the nonlinearities in the secondary path, which mainly arise from sensors, actuators and amplifiers used in the active noise control system, will cause instability and degrade the performance while using the FxLMS algorithm. In order to cope with this challenge, many new approaches have been proposed and fuzzy logic control is one of these. In this paper, a Takagi–Sugeon–Kang-type fuzzy logic control-based feedforward active noise control system with focus on the geometry configuration is introduced. In contrast to previous work, all physical paths are modelled by pure time delay transfer function and the acoustic feedback is added as part of inputs for the fuzzy logic control. Computational experiments are implemented within the Matlab/Simulink platform, and several case studies are presented with time and frequency domain analyses to demonstrate the cancellation ability of the proposed feedforward active noise control system and investigate the influence of distance ratio on the overall noise cancellation performance.

Previous studies have shown that choice behavior in pigeons is systematically affected by the response effort, such as force or locomotion between response keys, as well as a delay in reinforcement or the amount of reinforcement. The present study aimed to investigate choice behavior in reinforcement schedules in which distance between operanda was manipulated as a response effort from the point of view of generalized matching law. To do so, a distance schedule was developed to manipulate the distance between response keys. In this schedule, pigeons were required to produce either 4 or 10 responses. Interresponse distances, a measure of the distance as a response effort, were calculated by summing the distances between the locations of successive responses. The present study employed a concurrent-chain design in which variable-interval schedules and distance schedules formed the initial and terminal links, respectively, of the concurrent chain. The results showed a matching relation between the initial-links response ratio and the interresponse distance ratio in a condition where 10 responses were required in terminal-links, but not in the condition with 4 responses. This implies that response effort is an important factor in determining choice behavior, as well as other factors including rate or amount of reinforcement or delay in reinforcement. However, the present results could be confounded by the effects of the elapsed time before reinforcement. Thus, further research will be needed using a modified version of the present distance-choice procedure to isolate the effect of distance itself.

Previous studies utilizing jump-landing biomechanics to predict anterior cruciate ligament injuries have shown inconsistent findings. The purpose of this study was to quantify the differences and correlations in jump-landing kinematics between a drop-jump, a controlled volleyball-takeoff, and a simulated-game volleyball-takeoff. Seventeen female volleyball players performed these 3 tasks on a volleyball court, while 3-dimensional kinematic data were collected by 3 calibrated camcorders. Participants demonstrated significantly increased jump height, shorter stance time, increased time differences in initial contact between 2 feet, increased knee and hip flexion at initial contact and decreased peak knee and hip flexion for both left and right legs, and decreased knee–ankle distance ratio at the lowest height of midhip for the 2 volleyball-takeoffs compared with the drop-jump (P dz ≥ 0.8). Significant correlations were observed for all variables between the 2 volleyball-takeoffs (P ρ ≥ .6) but were not observed for most variables between the drop-jump and 2 volleyball-takeoffs. Controlled drop-jump kinematics may not represent jump-landing kinematics exhibited during volleyball competition. Jump-landing mechanics during sports-specific tasks may better represent those exhibited during sports competition and their associated risk of anterior cruciate ligament injury compared with the drop-jump.

Background and Aim: The sonographic assessment of airway in the preoperative period has encouraging results in predicting difficult laryngoscopy. Materials and Methods: The prospective, observational study was conducted on 120 patients scheduled for elective surgery requiring general anesthesia and tracheal intubation. The depth of the pre-epiglottic space (Pre-E), the distance from the epiglottis to the midpoint of the distance between the vocal cords (E-VC) was measured sonographically. Similarly, hyomental distance ratio (HMDR) was sonographically measured with head in neutral and extended positions. The primary outcome was the efficacy of Pre E/E-VC, HMDR for predicting difficult laryngoscopy (Cormack–Lehane [CL] Grade 3, 4). The secondary outcome was to correlate these parameters to CL grading. Results: Difficult intubation was observed in 12.5% of patients. The mean ± standard deviation (SD) of Pre E/E-VC ratio was 1.33±0.335, 1.62±0.264 and 1.87±.243, 2.22±.29 for CL Grade 1, 2, 3, and 4, respectively (P = 0.00). The mean ± SD of HMDR was 1.11±.35, 1.12±.29, and 1.07±.39, 1.04 ± 0.01 for CL Grade 1, 2, 3, and 4, respectively (P = 0.00). Pre E/E-VC ratio of more than 1.77 cm had 82% sensitivity, specificity 80%, whereas HMDR less than1.085 had sensitivity 75% and specificity 85.3%, in predicting difficult laryngoscopy (P = 0.00). Conclusion: The sonographic measurement of the Pre E/E-VC ratio is a better predictor of CL grading as compared to HMDR. The noninvasive prediction of CL grading can be precisely done by Pre-E/E-VC ratio (range: 0–1.425 corresponds to CL Grade 1; 1.425–1.77 ≈ CL Grade 2; 1.77–1.865 ≈ CL Grade 3, more than 1.865 corresponds to CL Grade 4).

This paper presents an experimental program investigating the behavior of high strength steel connections consisting of one bolt in double shear. A total of 24 bolted connections fabricated from three grades of high strength steel with the nominal yield strengths of 550 MPa, 690 MPa and 890 MPa were tested. The effects of end distance, edge distance and steel grade on the bolt bearing behavior were evaluated. The bolt hole elongation due to bolt bearing on high strength steel plate was measured and its implication on the plate bearing resistance was discussed. The test results were compared with Eurocode 3 and AISC 360-10 predictions and it was found that Eurocode 3 could be used conservatively to predict the bolt bearing resistance on high strength steel with nominal yield strength up to 890 MPa whereas AISC 360-10 method tends to overestimate the bearing resistance of the bolted connection. A regression analysis was performed based on the test data and those from the literature so that a more general method was proposed to predict the bolt bearing resistance on normal strength and high strength steel plate. Splitting failure was observed as a transitional failure mode between tearout failure and net cross-section failure. Splitting failure showed a lower resistance than the bolted connection with tear-out failure, therefore, a reduction factor was proposed to improve the prediction. The upper and lower boundaries of end distance to edge distance ratio for splitting failure were theoretically derived and experimentally verified.

The overall objective of this study is to predict the behavior of the fabrics in details overlooked the drape phenomenon using Fuzzy-C-Mean (FCM) method. In this paper, the fabric properties which are the weight, the bending rigidity B in three direction: warp, weft and skew direction and the shear rigidity G were preselected according to their influence on the drape parameters (the drape coefficient DC, the node number NN, the fold depth index FDI and the drape distance ratio DDR). The result showed that the drape phenomenon was classified into three classes: low drape, average drape and high drape. The values of drape parameters were discussed in this work.