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This article demonstrates the use of traffic density observations collected dynamically in the vicinity of probe vehicles. Fixed position sensors cannot capture the longitudinal evolution of local traffic density in the corridor. In this research, dynamic traffic density observations were collected in a naturalistic driving setting that was free of any controlled experiment biases. Speed from global positioning system and space headway from a light detection and ranging module was collected on one arterial and one freeway segment, 2 and 4 mi long, respectively. The combined data frequency was approximately 3 Hz. Space headway was used to estimate the local density and consequently to identify the density of a specific location in a corridor. Besides, driver behavior was characterized using the relationship between instantaneous speed and local density under different regimes of the Wiedemann car-following model. Macroscopic traffic stream models were used to investigate the relationship between dynamically collected instantaneous speed and local density. Using the longitudinal evolution of density, precise local density across the corridor can be obtained along with the leader and follower trajectories. A method to identify driver behavior across density ranges was developed for different facility types using a microscopic relationship between instantaneous speed and local density. Overall driving behavior on the freeway segment can be represented by translating the instantaneous speed and local density relationship to macroscopic stream models.

As an alternative to the classical assembly lines techniques, an approach is developed here considering another assembly system. It allocates the tasks on an assembly cell consists of a number of machines. The control is conducted using a new formulation which tends to minimize the total cost of the manufactured product. Thelower-bound approach of automatic assembly is considered, where it i flags two ways in dealing with breakdowns which may occur suddenly in processes. The proposed assembly system is mainly based on the fixed position layout, where the major component is stationary at a multiple-machine station which completes whole job. The assignment procedure is not completely for balancing as occurs in known line procedures which assign the tasks into a series of work stations. It tries to equalize the idle time on all machines, and exploits the situation that two or more machines process many more independent tasks simultaneously. The total cost of unit assembly is computed through two functions, the first is experimental and the second is analytical. The computer application of the approach confirms that the examined system is an efficient challenges and exhibits the capability of the approach itself.

Purpose To evaluate the difference between the preoperative marking methods for toric intraocular lens (IOL) implantations using an image-guided system (IGS) and the manual marking method in the same eye. Patients and methods In this retrospective case series, 82 patients (101 eyes) who underwent cataract surgery using both manual and IGS (VERION, Alcon Laboratories) marking were enrolled. First, preoperative reference marks were placed at 6 o'clock and 3 or 9 o'clock position under slit-lamp biomicroscope in the outpatient department using the manual method. Using the reference unit of IGS, the ocular surface data were captured and overlaid. The difference was then measured (preoperative axis misalignment). In the operating room, the orientation of the steep meridian of the manual method was determined based on this reference mark under the surgical microscope. Just before surgery, the digital degree gauge of IGS was overlaid on the ocular surface, and the difference was then measured (total axis misalignment). We calculated the intraoperative axis misalignment by subtracting preoperative axis misalignment from the total axis misalignment. Results Mean absolute preoperative, intraoperative, and total axis misalignment values were 3.87±3.95 degrees, 5.46±4.42 degrees, and 4.98±4.49 degrees, respectively. In preoperative, intraoperative, and total misalignment, the ratios of 10 degrees or greater were 10 (14.7%), 12 (17.6%), and 20 (19.8%) eyes, respectively. Conclusion The manual method that determines the fixed position of the toric intraocular lens (IOL) may cause large misalignment compared with the IGS, suggesting that using manual method could sometimes result in a large misalignment of toric IOL implantation.

Visual search is facilitated when the target is repeatedly encountered at a fixed position within an invariant (vs. randomly variable) distractor layout—that is, when the layout is learned and guides attention to the target, a phenomenon known as contextual cuing. Subsequently changing the target location within a learned layout abolishes contextual cuing, which is difficult to relearn. Here, we used lateralized event-related electroencephalogram (EEG) potentials to explore memory-based attentional guidance ( N = 16). The results revealed reliable contextual cuing during initial learning and an associated EEG-amplitude increase for repeated layouts in attention-related components, starting with an early posterior negativity (N1pc, 80–180 ms). When the target was relocated to the opposite hemifield following learning, contextual cuing was effectively abolished, and the N1pc was reversed in polarity (indicative of persistent misguidance of attention to the original target location). Thus, once learned, repeated layouts trigger attentional-priority signals from memory that proactively interfere with contextual relearning after target relocation.

When I started fieldwork among the Maka in SE Cameroon in 1971 I was suprised that for them kinship was hardly about ascribing people a fixed position. In retrospect this makes me realize how deeply Talcott Parsons’ famous pattern variables – notably ‘ascription’ versus ‘achievement’ influenced our perspective. But Maka people turned out to be true masters in ‘working’-with kinship, constantly ‘discovering’ kin in unexpected contexts, making creative equations and switch-es. My subsequent research in the area (up till now) highlighted how over time this plasticity of their kinship arrangements increased with growing urbanization and even more with transcontinental migration. Cameroon’s famous ‘bush-fallers’ have developed their own ways for ‘working’ with kinship. However, this plasticity should not only be studied as stemming from new and shifting conditions. I hope to show as well that such a more dynamic view on kinship is valuable for re-evaluating classical kinship theory.

The paper present the result of the study on the use of simulation software of ANSYS R15.0 version in attempt to simulate the load which is working on a screwed shaft of a shaping machine. This shaft was broken down during normal working and within limit of its life time. Therefore, the simulation would try to find out the cause of the failure. In order to simulate the load, the mechanical properties and chemical composition of the shaft were used as the input for modeling. The shaft is made of medium carbon steel of S 45 C in round shape. The finite element method (FEM) was used for analyzing. The modeling was started with a 3D redrafting the real dimension of the shaft in a computer aided design (CAD) model, then imported to the ANSYS system into FEM format. The mechanical and physical properties of the material was entered as the engineering data. Meshing was made to divide the component into several small elements. A combination of static and torsion load was applied to the shaft with a fixed position. The simulation results shown that von mises stress of 4.546 MPa was achieved. While, the first principal stress of 4.518 MPa, the third principal stress of 0.538 MPa. Other result revealed that the displacement was 0.001602 mm. Simulation also indicate that failure occurs at the slot a place where the pin was inserted to lock between the shaft and the bevel gear. The result is in accordance with the real failure of the shaft. To conclude, the ANSYS with FEM modeling has succeeded to simulate the failure of the screwed shaft.

This work presents the results of U–Th–Pb (LA–ICP–MS) geochronological study of detrital zircons from terrigenous deposits of the Olokit zone of the Baikal–Patom fold–thrust belt of the Siberian Craton. It was established that the age of deposits of the Olokit Formation is in the range of 0.86–0.72 Ga. Archean and Early Proterozoic rocks of the southern part of the Siberian Craton and the Neoproterozoic complexes of the Baikal–Muya belt were the sources of detrital zircons of the terrigenous rocks of the Olokit zone. There is no evidence of rocks that could have been the sources of Mesoproterozoic (1.08–1.46 Ga) and Late Paleoproterozoic (1.65 Ga) detrital zircons for the deposits of the Ondok paleo-uplift in the Olokit zone, in the Baikal mountain region, and in the Siberian Craton. The data obtained and the results of paleomagnetic reconstructions indicate that Siberia and Laurentia in the Meso- and Early Neoproterozoic were in a fixed position relative to each other; an unknown continental block composed of Mesoproterozoic rocks could have occupied the space between them.

The layout of fixed-position assembly islands (FPAI) is widely used for producing fragile or bulky products. With the increasing customised demand and unique operation patterns, manufacturing pract...

Nowadays, wood-based panel producers intend to lower costs by decreasing the pressing time and reducing resin consumption. Therefore, the aim of this work is to understand the influence of the pressing operating conditions (pressing time and pressing program) on the performance of particleboards (PBs) bonded with a UF resin (alkaline–acid process). For this purpose, several trials were carried out using a computer-controlled laboratory scale hot-press with a press cycle simulating a continuous press and a fixed position laboratory scale hot-press, varying the venting, the total pressing time ( 90 s) and the gluing factor (resin content—4, 5 and 6 mg resin solids/g oven dry wood). Analysis of variance (ANOVA) was performed in order to evaluate the significance level of the effects of these parameters on PB’s physico-mechanical properties and formaldehyde content. The main results of the study were: to decrease formaldehyde content, resin content (RC) should be increased for pressing times higher or equal to 90 s or decreased for pressing times lower than 90 s; to increase internal bond, RC must be increased for pressing times equal or higher than 90 s, or decreased for pressing times lower than 90 s.

Walk-In-Place (WIP) is a technique in which users perform walking or jogging-like movements in a stationary place to move around in virtual environments (VEs). However, unintended positional drift (UPD) while performing WIP often occurs, thus weakening its benefits of keeping users in a fixed position in a physical space. In this paper, we present our preliminary study exploring whether users’ gaze while WIP affects the direction of the UPD. Participants of the study jogged in a VE five times. Each time, we manipulated their gaze direction by displaying visual information in 5 different locations in their view. Although a correlation between the gaze and UPD direction was not found, we report the results from this study, including the amount of observed drift and preferred location of visual information, and discuss future research directions.

Back pains are the most frequent musculoskeletal disorders among dentists, exposed to many work-related risk factors. We aimed to assess the prevalence and intensity of back pains as well as the impact of some work behaviors among a large sample of dentists. Data from 1004 French dentists were collected via an Internet questionnaire. Neck, upper back and lower back pains prevalence, intensity (0–10 scale) and consequences on work were studied, as well as sex, age, years of practice, working position, type of seat, stretching on work days. Dentists were 77.9% to report chronic back pains, with intensity from 3.9 to 4.3 according to location. Women reported more frequent and intense pains than men in neck and upper back (OR 1.5). Age and years of practice were associated with more intense pains (OR up to 3.9), dentists alternating standing and sitting positions reported more frequent and more intense pains in upper and lower back (OR up to 1.5) than those with a fixed position, be it sitting or standing. Prevalence and intensity of back pain are important among dentists and increase greatly over working life. Preventive methods such as ergonomics exist and awareness should be raised among dentists and dental student. These slides can be retrieved under Electronic Supplementary Material.

People with whiplash-associated disorders (WADs) report difficulty with quick head movements and cervicoocular dysfunction. Changes in coordination between eye movement and neck muscle activity may be involved.To examine whether activity of superficial and deep neck muscles increases with eye movement when the head is held in a fixed position, whether this differs between directions and speed of eye movement, and whether this is modified in WAD.Convenience case series with unmatched controls.Research laboratory.Nine individuals with chronic WAD grade II and 11 pain-free controls.Electromyography (EMG) was recorded from muscles that could act to rotate the neck to the right (right obliquus capitis inferior [OI], multifidus [MF], splenius capitis [SC], and left sternocleidomastoid [SCM]) with intramuscular or surface electrodes in 9 WAD participants and 11 pain-free controls. Eyes were rotated without head movement to track slow and medium-speed targets to the right or left, and as fast as possible (FP).Amplitude of EMG.In controls, SCM and SC EMG increased with right gaze (all P's .03). EMG of the deep OI muscle increased in both directions (P .001). WAD involved counterintuitive greater activity of SCM with left rotation across speeds of eye movement (SC with slow movement, P .036), decreased OI EMG with gaze left (P .019), and no change in MF EMG (P .6) in either gaze direction. For FP tasks, EMG of all muscles was greater than slower speeds in controls (all P's .0001), but not WAD (all P's .33).Coordination between neck muscle activity and eye movements with increasing speed is modified in WAD. Contrasting changes are present in deep and superficial neck muscles with implications for neck function that may explain some common WAD symptoms.IV.

An analysis of the process of creating bobbins from glass and basalt threads at high winding rates, which makes it possible to estimate the increase in the mass of the bobbins in the course of taperedmulti-layer cross cone winding, is performed. The parameters of the process of creating bobbins, in which the fixed position of the loops of the thread on the body of the coil at the moment the direction of travel changes, are established.

This work carries out an analysis on fault tolerance in multirotor vehicles, particularly for an hexarotor one, where such feature is achieved by shifting the center of mass in case of a motor failure. It will be shown that, for an hexarotor vehicle, for each of the possible motor failures, there exists an optimal fixed position for the center of mass, in order to keep independent control of four degrees of freedom, and to obtain the best maneuverability. The performance of this solution will be compared with a previous design based on motor reconfiguration in case of a motor failure.

This study aimed to investigate the wear failure changes of spindle hook teeth and the reasons for such failure during field work. Spindle samples were obtained from a fixed position of the spindle bar under different field picking area conditions and combined with the spatial distribution characteristics of cotton bolls in Xinjiang. After cutting a spindle sample, a scanning electron microscope and an energy spectrum analyzer were used to characterize the micromorphology and element composition of the hook tooth surface and cross section under different working area conditions. The wear parameters of the hook teeth were then extracted. The results showed that the thickness of the coating on the surface of the hook tooth used in this study was between 66.1 µm and 74.4 µm. The major chemical element was chromium, with a small amount of nickel. During the field picking process, failure of the coating on the surface of the hook teeth initially appeared on the tooth tip and tooth edge, and then spread to the entire hook tooth surface. The wear failure of the hook teeth resulted from abrasive wear, oxidative wear, and fatigue peeling. As the picking area increased, the wear area of the hook teeth increased exponentially, while the wear width increased linearly. When the field picking area reached 533.33 ha, the maximum change rate of the wear area was 2.33 × 103 µm2/ha, and the wear width was 1.84 µm/ha. During field work, the thickness of the coating decreased from the cutting surface to the tooth edge, and the wear rate gradually increased. The wear rate at Position 1 was the slowest, at 0.01 µm/ha, and the wear rate at Position 5 was the fastest, at 0.25 µm/ha.

In this paper, a quasiparticle concept was proposed to understand the branched flow of light phenomenon. Combined with the geometrical optical theory, we successfully established a model to simulate the branched flow of light with this novel perspective. Our model owns an intuitive physics picture, without losing generality. Moreover, we demonstrated that a special structure with the fixed position and specific refractive value of quasiparticles can be designed, a controllable branched flow pattern of light will be correspondingly attained for future experimental guidance.

Background Against a backdrop of declining tobacco use, e-cigarette markets are growing. The UK now has a higher percentage of e-cigarette users than any other European country. These developments have prompted fierce discussions in scientific, advocacy and policy communities about how best to respond. This article is one of the first to examine the role of evidence in these debates. Methods We analysed 121 submissions to two Scottish policy consultations on e-cigarettes (in 2014 and 2015) and undertook interviews with 26 key informants in 2015–2016, following up with a sub-set in 2019–2020. All data were thematically coded, and our analysis was informed by insights from policy studies and the sociology of science. Results First, we affirm previous research in suggesting that e-cigarettes appeared to have triggered a breakdown of old public health alliances. Second, we demonstrate that, amid concerns about research quality and quantity, actors are guided by normative outlooks (and/or economic interests) in their assessments of evidence. Third, we show that, despite describing e-cigarette debates as contentious and polarised, actors engaging in Scottish policy debates exhibit a spectrum of views, with most interviewees occupying an uncertain ‘middle ground’ that is responsive to new evidence. Fourth, we suggest that the perceived divisiveness of e-cigarette debates is attributed to recurrent media simplifications and tensions arising from the behaviours of some actors with settled positions working to promote particular policy responses (including by strategically enrolling supportive evidence). Fifth, we argue that the actions of these actors are potentially explained by the prospect that e-cigarettes could usher in a new tobacco ‘policy paradigm’. Finally, we show how scientific authority is employed as a tool within these debates. Conclusions E-cigarette debates are likely to reconcile only if a clear majority of participants in the uncertain ‘middle ground’ settle on a more fixed position. Our results suggest that many participants in Scottish e-cigarette debates occupy this ‘middle ground’ and express concerns that can be empirically assessed, implying evidence has the potential to play a more important role in settling e-cigarette debates than previous research suggests.

Runway-style breeding ponds are favored by more and more breeding owners. However, most of existing runway-style breeding pond feeding devices have the disadvantages of single function, fixed position and poor pertinence. This article designs a multi-point synchronous feeding device, which mainly includes overall design, storage mechanism design, conveying mechanism design and feeding mechanism design. The device realizes multi-point simultaneous feeding of runway-style breeding ponds, improves the feeding efficiency.

Beside the manufacturing of finished parts by Incremental Sheet Metal Forming (ISF), final operations within the process chain can also be realized with this technology. The technological capabilities of performing incremental (hole-)flanging operations for sheet metal parts has been investigated in research context. The current topic focusses on the transfer of the incremental forming technology to manufacture tubular parts. An incremental collar forming process was developed where all motions are executed by the forming tool. Due to the fixed position of the workpiece, tubes, as well as pipes can be branched. Stainless steel tubes made of 1.4404 (316L) with an outer diameter of 54 mm and a wall thickness of 1.5 mm were used for experimental evidence of functional capability of the incremental collaring process. The influence of different pre-hole geometries and forming tool shapes on the properties of the collar (e. g. geometrical accuracy, wall thickness) was investigated.

OBJECTIVES Oculogyric crisis is a dystonic movement disorder characterized by continuous contraction of the ocular muscles and spasmodic movements of the pupils in a fixed position, usually upward. METHODS In this case report, an early-stage acute oculogyric crisis due to low-dose olanzapine in a 15-year-old adolescent boy is presented. RESULTS To the best of our knowledge, this is the first report showing that acute oculogyric crisis can develop with low-dose olanzapine administration. CONCLUSIONS Even though second-generation antipsychotics are safer than conventional antipsychotics in terms of extrapyramidal adverse effects, this possibility should always be taken into consideration through this case report.

Vocatives are noun phrases that are generally used as calls to attract an addressee’s attention or as addresses to maintain contact with her/him. In her 2014 book, Virginia Hill analyzes vocatives as forms of address; they are converted to syntax as nominal functional projections in the form of vocative phrases. Drawing on work by Speas and Tenny (2003) and Moro (2003), she further posits that vocatives merge as arguments of a speech act phrase in the left periphery. This merging site, Hill 2014 and others (e.g., Slocum 2016) argue, is fixed. This is so despite the fact that vocatives may appear in different positions in their host clause. Under this account, pre-vocative elements appear in that location as a result of movement. This paper presents counterevidence to this argument from Arabic. Using naturally occurring data, mainly from Twitter, the paper shows that Arabic vocatives do not merge in a fixed position in the left periphery. Rather, they are parenthetical adjuncts whose relationship with their host clause is minimally constrained. If correct, the analysis serves as an invitation for a closer and more data-driven look at vocatives in other languages, including those in which vocatives have already been explored.

International audience; When a disaster occurs, during a long period of time people suffer to have no means to communicate with their relatives. The presented work aims at proposing a solution composed of a ground station located nearby the damaged area coupled with a swarm of drones. The ground station plays the role of a gateway between cellular networks, that are still up but out of reach of people, with drones that carry messages from and to people located in the disastered region. We analyze the possibility of deploying drones with fixed positions and a more flexible solution allowing drones to move but at the cost of intermittent communications, allowing only sms-like messages. We show that using the same number of drones, allowing drones to move improves dramatically the coverage of people with respect to a FANET in which drones stay at a fixed position. We also show that even for a very restricted number of drones, for reasonable communication ranges, almost all the people benefit from an important average connected time.

A 3-year-old boy was seen for failure to thrive and progressively stiffening muscles. He was a full-term child, third in the family, born of non-consanguineous marriage. He was noted to have some jerky movement of the limbs and had a fixed position of both upper and lower limbs. He also had failure to thrive. He was seen by a pediatric orthopedic surgeon who diagnosed arthrpgryposis multiplex. Physiotherapy was recommended but this did not make much difference. He had delayed milestones. He continued to have jerky movements of his limbs and there was persistent failure to thrive.

Magnification devices improve direct and indirect vision and precision being significantly higher in microscope use compared to the loupes. Dental loupes are the most commonly used devices for magnification, due to the more affordable prices and the ease of use without major changes in the working protocol and ergonomics. Loupes primary benefits reported refers to ergonomics and posture, restoration evaluation/detection and overall treatment quality. There are some disadvantages that limit the use of loupes among dentists: lack of fixed position (fine movements of the dentist's head disturb the image of the magnified operating field); the need to change the loupes to achieve different magnification. On the contrary, the use of a dental microscope require minimum adjustment and effort so as to reduce postural deviation while working. It has been more than 30 years since dental practitioners raised the issue of using dental operating microscopes (DOM) in restorative dentistry, identifying the benefits of magnification in diagnosis and treatment steps. The growth is evident in recent years, maybe because of the familiarity of dentists with dental microscopes which have already become implicit endowment for endodontic specialists. Fiber optic lighting is the key factor that complements the magnification offered by the microscope so that treatments can now be performed under increased safety conditions and in conditions of significantly higher quality than in the past. Since the beginning of the 2000s the principles of minimally invasive dentistry have been widely promoted in dentistry. These principles are major impetus for the use of microscope by dentists. Working with magnification leads dentists to be more conservative with dental tissues.

The formation of armored vehicle formation achievement and transforming are important research contents of vehicle formation control. Especially for the situation of unmanned armored vehicle formation. This paper combines the virtual navigator method and the behavior-based bait-predator method, and applies it to the formation achievement and transforming control of four unmanned armored vehicle formations. The target position is used as a bait to realize flexible transforming between linear, triangular and diamond formations. This method can prevent the formation leader from losing control due to the incapacitation of the formation leader, and does not specify the fixed position of the vehicle in the formation, which greatly guarantees the stability of the formation and the flexibility of formation transforming. The simulation experiment also proves that the method has good effect on the formation and formation transforming of vehicle formation.

International audience; Target expansion techniques facilitate pointing by enlarging the effective sizes of targets. As opposed to the numerous studies on target expansion solely focusing on optimizing pointing, we study the compound task of pointing at a Point of Interest (POI) and then interacting with the POI menu in handheld Augmented Reality (AR). A POI menu in AR has a fixed position because it contains relevant information about its location in the real world. We present two techniques that make the cursor jump to the closest opened POI menu after pointing at a POI. Our experimental results show that 1) for selecting a POI the expansion techniques are 31 % faster than the baseline screen-centered crosshair pointing technique, 2) the expansion techniques with/without a jumping cursor to the closest opened POI menu offer similar performances and 3) Touch relative pointing is preferred by participants because it minimizes physical movements.

This paper presents a smart crack detection system using genetic algorithm (GA) for a cantilever beam. The accuracy of prediction is optimized by performing parametric optimization of the first three natural frequencies. The three modes of natural frequencies are obtained from the experimental procedures and are optimized to reduce the percentage of error in predicting the relative crack position and crack depth from a fixed position. Comparison of analytical method is in agreement with the experimental values as the error percent between the experimental and predicted values is below 10%.

In hermaphroditic species, sexual interference can drive the evolution of dichogamy, where sporophylls (reproductive parts) are separated in time. However, the separation of sporophylls can lead to pollination inaccuracy, especially in movement-assisted dichogamy, where sporophylls alter their position over time. Is pollination inaccuracy minimised by the second sporophyll taking the exact position of the first? Are the sporophylls optimally positioned and stable in their respective active phases? We address these questions inClerodendrum infortunatum, a protandrous, movement-assisted dichogamous species. We made predictions from optimality arguments, and tested these by measuring sporophyll angles over time, by experimentally manipulating flowers, and by estimating correlates of the resultant fitness, taking into account pollen export, pollination inaccuracy and the resultant total pollen delivered. Contrary to expectation, anthers do not have a fixed position in the male phase, and pollination inaccuracy is high. Further, when pollen load is highest, anthers are paradoxically not positioned at the pollen export peak. Also, pollen export and pollination accuracy peaks do not align. This seeming maladaptiveness of anther positioning nevertheless results in highest overall male fitness, measured as the total pollen delivered over the entire male phase. Instead of a simple positional exchange of sporophylls, stamens display a more complicated dynamic strategy which appears close to optimal even though naive measures of pollination inaccuracy are high. Such a strategy of maximising overall male fitness, integrating over the dynamics of stamen trajectory, could well be a general characteristic of protandrous movement-assisted dichogamy.

Seafloor observatory are becoming more and more important in multidisciplinary observations of the seabed, but real-time, long-term and fixed locations observation are still difficult to achieve. This paper describes a new technology that divides the seafloor observatory into three modules: mobile docker, scientific instrument cabin and in-situ gravity station and uses buoys or photoelectric composite cables to meet the above three requirements. After design and manufacture, the workflow of the seafloor observatory was simulated through a pool test. The handling performance of the mobile docker, the reliability of the docking between the three modules and the performance of the in-situ gravity station to adjust its attitude were proved. It has been preliminarily proved that this seafloor observatory has application value.

Assembly stations are important hubs that connect massive material, information, human labor, etc. The fixed-position assembly systems for complex products may deal with hundreds of thousands of processes, making them vulnerable to manufacturing exceptions. Many scheduling problems were described and solved in the past decades, however, the gap between theoretical models and industrial practices still exist. To achieve a practical method for the dynamic scheduling in case of exceptions while reducing the impact brought by the exceptions, an Intelligent Collaborative Mechanism (ICM) was proposed where negotiations on resource configuration may happen among tasks (i.e. assembly processes). The intercommunication among resources was guaranteed by the data-driven ICM framework. The Petri-net-based workflow analysis and the constraint matrix can pick out the tasks that are currently not bound by other ones. The dynamic priority of the processes was defined and obtained using grey relational analysis. The matching strategy among the selected tasks and operators can provide a scheduling plan that is close to the initial plan, so the assembly systems may remain effective even when exceptions occur. The proposed models were analyzed in a case scenario, where the impact brought by exceptions can decrease by 44.3% in terms of the operators’ utilization rate, and by 60.26% in terms of the assembly time. This research has provided a practical strategy to improve the flexibility and effectiveness of assembly systems for complex products.

Purpose Pterygia are much more common nasally than temporally. Ultraviolet (UV) radiation is a major risk factor. Coroneo proposed that the nasal preference is caused by the "peripheral light focusing effect," (PLF), in which UV at an oblique angle passes through temporal cornea and is concentrated on and damages nasal limbal stem cells. This study evaluates whether the PLF is sufficient to explain the nasal preference. Methods Whereas Coroneo and colleagues derived the maximum PLF intensity gain (UV concentration factor) as a function of incident angle (i.e., different nasal limbal positions were used for different incident angles) the current analysis derived intensity gain at a fixed position such at the nasal corneo-limbal junction (CLJ). This provided a measure of the total PLF irradiation at this position, which was compared to total direct irradiation of nasal and temporal limbus at the corresponding positions (e.g., CLJs). In Part 1, analysis was performed like that of Coroneo, using horizontally incident UV; in Part 2, the analysis was extended to include incident rays above and below the horizontal. Results In both part 1 and part 2 of the study, the limbal UV irradiation of the nasal limbus from the PLF was not sufficient to explain the strong nasal location preference of pterygia. Conclusions The analysis calls into question the PLF explanation of nasal location preference. Other explanations of the nasal preference, and of pterygium pathogenesis, should be considered, such as temporal to nasal tear flow carrying substances such as cytokines to the nasal limbus.

Immersive content has become a popular medium for storytelling. This type of content is typically accessed via a head-mounted visual display within which the viewer is located at the center of the action with the freedom to look around and explore the scene. The criteria for subtitle position for immersive media still need to be defined. Guiding mechanisms are necessary for circumstances in which the speakers are not visible and viewers, lacking an audio cue, require visual information to guide them through the virtual scene. The aim of this reception study is to compare different subtitling strategies: always-visible position to fixed-position and arrows to radar. To do this, feedback on preferences, immersion (using the IPQ questionnaire) and head movements was gathered from 40 participants (20 hearing and 20 hard of hearing). Results show that always-visible subtitles with arrows are the preferred option. Always-visible and arrows achieved higher scores in the IPQ questionnaire than fixed-position and radar. Head-movement patterns show that participants move more freely when the subtitles are always-visible than when they are in a fixed position, meaning that with always-visible subtitles the experience is more realistic, because the viewers do not feel constrained by the implementation of subtitles. Resumen Los contenidos inmersivos se han convertido en un medio interesante para contar historias. A este tipo de contenido normalmente se accede con unas gafas de realidad virtual, a través de las cuales el usuario, que se encuentra en el centro de la acción, tiene la libertad de mirar y explorar la escena libremente. Los criterios para determinar la posición de los subtítulos en contenidos inmersivos todavía no se han definido. También se necesitan mecanismos de guía para indicar dónde está la persona que habla cuando está fuera del campo de visión y los usuarios no pueden contar con el audio para guiarse. El objetivo de este estudio de recepción es comparar diferentes estrategias de subtitulación: subtítulos siempre visibles con subtítulos colocados en posiciones fijas, y flechas con radar. Para ello, se han recopilado los comentarios de 40 participantes (20 oyentes y 20 con pérdida auditiva) sobre las preferencias, la inmersión (con el cuestionario IPQ) y los patrones de movimiento de cabeza. Los resultados muestran que los subtítulos siempre visibles con flechas son la opción preferida. Además, estas soluciones obtuvieron mejores puntuaciones en el cuestionario IPQ. Los patrones de movimientos de cabeza muestran que los participantes se movían más libremente con los subtítulos siempre visibles, lo que supone que con este tipo de subtítulos la experiencia es más realista ya que los usuarios no se sienten cohibidos por la integración de los subtítulos. Résumé Les contenus immersifs sont devenus un moyen intéressant de raconter des histoires. Ce type de contenu est généralement accessible avec des lunettes de réalité virtuelle, avec lesquelles l’utilisateur est au cœur de l’action et à la liberté de regarder et d’explorer la scène librement. Les critères pour définir la position des sous-titres dans ce contenu n’a pas encore été définie. Des mécanismes de guidage sont également nécessaires pour indiquer où se trouve le locuteur lorsqu’il est hors du champ de vision et que les utilisateurs ne peuvent pas se fier à l’audio pour être guidés. L’objectif de cette étude de réception est de comparer différentes stratégies de sous-titrage : des sous-titres toujours visibles avec des sous-titres placés à des positions fixes et des flèches avec le radar. À cet égard, les commentaires de 40 participants (20 auditeurs et 20 malentendants) ont été recueillis sur les préférences, l’immersion (avec le questionnaire IPQ) et les schémas de mouvements de la tête. Les résultats montrent que les sous-titres qui sont toujours visibles avec des flèches sont l’option préférée. En outre, ces solutions ont obtenu de meilleurs résultats dans le questionnaire IPQ. Les modèles de mouvements de la tête montrent que les participants se sont déplacés plus librement avec les sous-titres toujours visibles, ce qui signifie qu’avec ce type de sous-titres, l’expérience est plus réaliste car les utilisateurs ne sont pas gênés par l’intégration des sous-titres.

Carbon fiber reinforced polymers (CFRP) are lightweight but strong composite materials designed to reduce the weight of aerospace or automotive components - contributing to reduced greenhouse gas emissions. A common manufacturing process for carbon fiber tapes consists of aligning tows (bundles of carbon fiber filaments) side by side to form tapes via a spreading machine. Tows are pulled across metallic spreading bars that are conventionally kept in a fixed position. That can lead to high variations in quality metrics such as tape width or height. Alternatively, one could try to control the spreading bars based on the incoming tows' profiles. We investigate whether a machine learning approach, consisting of a supervised process model trained on real data and a process control model to choose adequate spreading bar positions is able to improve the tape quality variations. Our results indicate promising tendencies for adaptive tow spreading.

In this work, we present LIBRE: LiDAR Benchmarking and Reference, a first-of-its-kind dataset featuring 10 different LiDAR sensors, covering a range of manufacturers, models, and laser configurations. Data captured independently from each sensor includes three different environments and configurations: static targets, where objects were placed at known distances and measured from a fixed position within a controlled environment; adverse weather, where static obstacles were measured from a moving vehicle, captured in a weather chamber where LiDARs were exposed to different conditions (fog, rain, strong light); and finally, dynamic traffic, where dynamic objects were captured from a vehicle driven on public urban roads, multiple times at different times of the day, and including supporting sensors such as cameras, infrared imaging, and odometry devices. LIBRE will contribute to the research community to (1) provide a means for a fair comparison of currently available LiDARs, and (2) facilitate the improvement of existing self-driving vehicles and robotics-related software, in terms of development and tuning of LiDAR-based perception algorithms., Comment: Accepted for oral presentation at IEEE Intelligent Vehicles Symposium (IV2020), https://2020.ieee-iv.org/ LIBRE dataset available at https://sites.google.com/g.sp.m.is.nagoya-u.ac.jp/libre-dataset/ Reference video available at https://youtu.be/rWyecoCtKcQ

The paper is devoted to the algorithm for the placement of orthogonal polyhedrons represented as a set of orthogonal objects with a fixed position relative to each other. The proposed algorithm is implemented invariantly with respect to the dimension of the objects to be placed, which makes it applicable for solving the cutting and packing problems of arbitrary dimension. Examples of the placement of two-dimensional and three-dimensional orthogonal polyhedrons are presented.

Extracting a palm region with fixed location from an input hand image is a crucial task for palmprint recognition to realize reliable person authentication under unconstrained conditions. A palm region can be extracted from the fixed position using the gaps between fingers. Hence, an accurate and robust hand segmentation method is indispensable to extract a palm region from an image with complex background taken under various environments. This paper proposes a hand segmentation method for contactless palmprint recognition. The proposed method employs a new CNN architecture consisting of an encoder-decoder model of CNN with a pyramid pooling module. Through a set of experiments using a hand image dataset, we demonstrate that the proposed method exhibits efficient performance on hand segmentation.

Imagine a tightrope walker, walking along a tightrope, holding a long, light rod. To help her balance, the performing artist continually moves the rod, changing the angle of the rod to maintain a constant – her balance in space. If she were to hold the rod in a fixed position, what would happen? She would fall off. In other words, the variation of the rod has the function of maintaining the deeper continuity which enables the artist to make it to the other end, alive. In this essay, the tightrope walker offers a metaphor for dispute resolution systems. In order for a dispute resolution system to survive, it needs to be agile and adapt to changing circumstances; to evolve – just like a tightrope walker.

This paper investigates the modelling and model checking of a real-world distributed railway interlocking system algorithm using UPPAAL. Interlocking systems for specific railway networks are verified by instantiating a generic (re-configurable) model with configuration data that describes the network and involved trains. There are three variants of the generic model: (1) The first variant includes the minimum required operations such as reserving a segment for a train, locking a point in a fixed position, and moving a train. (2) A restricted variant that uses a more strict operational order. (3) A variant that extends the first variant with a cancel operation that removes reservations and locks. Verification experiments are carried out on instances of all variants in order to check their correctness and compare their performance. The scalability of the three variants has been investigated with networks of varying sizes. Finally, for a real-world railway network, instances of the three model variants have been successfully verified.

This paper presents a magnetic field based 4-degrees of freedom (DOF) localization approach for unmanned aerial vehicles (UAVs). The sensor system is comprised of two elements, a 3-axis magnetic field source attached to the mobile object, i.e. on the UAV, and a 3-axis magnetic field sensor being on a fixed position, e.g. ground. The transmitters are driven by signals in the low radio frequency (RF) range which ensures robustness against reflections and absorbing objects, making it ideally suitable for indoor usage. Additionally, its accuracy increases with decreasing distance between transmitter and receiver. Our system is thus complementary to vision based systems which experience difficulties when navigating close to ground level. This is mainly caused by their focal length and the loss of features. The proposed concept is validated in simulation and additionally with a rapid-prototyping-based experimental setup.

A historical overview of the techniques used to observe traffic conflicts is followed by a discussion of the latest progress in this area. There are two distinct types of observations: from a fixed position and from a moving position. The early observations were made by humans from a fixed position. Subjectivity and inaccuracy were the main drawbacks. Modern techniques include video, radar, and LiDAR sensors applied at fixed or moving positions. Three existing techniques are: video sensor placed at a stationary position, LiDAR placed at a stationary position, and radar combined with video installed in an instrumented vehicle. Selected technological details of the three techniques are presented and their performance in detecting and tracking objects is discussed.

Accompanied with globalisation, companies are confronted with new competitors and price competitions. In order to meet these challenges manufactures strive to increase their efficiency throughout the value stream. Especially special machine manufactures assembling in fixed position assembly islands show a high non-value adding share, since their assembly and logistical processes are characterised by a low degree of standardisation and maturity. This leads to a high spread of throughput times and increases the risk of delivery delays. To improve this weakness, this paper presents an approach to increase the degree of standardisation and to lower and stabilise the throughput time. The new approach bases on heuristics for packing problems and applies them to the material supply. By that, the allocation of the supplied components is optimised, as a result of which search times and path lengths for walking and transporting are shortened and the value adding time share is increased.

Spindle preload has a decisive influence on the performance of precision machine tool spindle and is usually defined as a constant parameter in most theoretical studies. In fact, the spindle preload changes with the operating conditions, such as temperature and speed of spindle. An in-depth understanding of preload variation mechanism becomes important for preload optimization and adjustment. Although some scholars have theoretically studied the relationship between operating conditions and preload, the results lack experimental verification since there is no effective way to measure the preload on-line. In this paper, a special pressure transducer for the preload continuous measurement of fixed position preload spindle was proposed, and the coupling effect of temperature and speed on the preload was experimentally tested and theoretically simulated based on the finite-element-method-based thermo-mechanical model considering the nonlinearity of bearing stiffness. The results show that the spindle speed contributes to the increase of the spindle preload, while the temperature causes a decrease of the preload. The preload variation is the trade-off effect of temperature and speed on it. The deformation of the spacer caused by temperature and speed is the most important factor leading to the change of the spindle preload.

Background Action-planning and execution deficits in children with hemiplegic cerebral palsy (HCP) are potentially due to deficits in the integration of sensory information, such as vision, with motor output. Aims To determine differences in anticipatory visual patterns in children with HCP compared to typically developing (TD) children, and to assess visuomotor coordination in children with HCP. Methods and procedures We included 13 children with HCP (Age = 6.8 + 2.9 yrs) and 15 TD children (Age = 5.8 + 1.1 yrs). The experimental task used in this study is a valid action-planning task, which consisted of initially reaching and grasping an object placed at a fixed position, followed by placing the object in a random target position. Visual patterns were recorded using a head-mounted eye-tracker system and arm movements were recorded using motion capture (120 Hz). Outcomes and results Children with HCP had delayed anticipatory gaze time and longer latency than TD children during the planning and execution phases. Children with HCP also had a higher frequency of gaze shifts, longer reaction times (RT) and movement times (MT) than TD children. Conclusions and implications Children with HCP may have deficits in anticipatory vision, which potentially affected planning and executing a goal-directed action. Therapeutic interventions focusing on improving visuomotor coordination may improve the motor performance in children with HCP.