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Roll forming is increasingly used in the automotive industry for the manufacture of structural and crash components from ultra-high-strength steel (UHSS). Springback and end flare are common shape defects in roll forming and increase with material strength. The conventional roll forming process is limited to the manufacture of components with a uniform cross section while flexible roll forming can produce parts with variation in width and depth. In this paper, the flexible roll forming of an automotive component from three different high-strength sheets of steel is investigated. The experiments are carried out with a flexible roll forming prototyping facility and combined with finite element analysis. The study shows that the flexible roll forming of high-strength automotive components is possible. Springback and end flare depend on the material strength and the forming sequence and can be reduced with a flexible forming approach where the material is first overbent followed by bending back. Wrinkling of the flange was observed but the severity of wrinkling reduced with an increasing number of forming passes.

Integrated photonic circuits are key components for photonic quantum technologies and for the implementation of chip-based quantum devices. Future applications demand flexible architectures to overcome common limitations of many current devices, for instance the lack of tuneabilty or built-in quantum light sources. Here, we report on a dynamically reconfigurable integrated photonic circuit comprising integrated quantum dots (QDs), a Mach-Zehnder interferometer (MZI) and surface acoustic wave (SAW) transducers directly fabricated on a monolithic semiconductor platform. We demonstrate on-chip single photon generation by the QD and its sub-nanosecond dynamic on-chip control. Two independently applied SAWs piezo-optomechanically rotate the single photon in the MZI or spectrally modulate the QD emission wavelength. In the MZI, SAWs imprint a time-dependent optical phase and modulate the qubit rotation to the output superposition state. This enables dynamic single photon routing with frequencies exceeding one gigahertz. Finally, the combination of the dynamic single photon control and spectral tuning of the QD realizes wavelength multiplexing of the input photon state and demultiplexing it at the output. Our approach is scalable to multi-component integrated quantum photonic circuits and is compatible with hybrid photonic architectures and other key components for instance photonic resonators or on-chip detectors.

The need for a better understanding of radical uncertainty might have never been greater. Ill-preparedness for natural hazards, a resurgence of serious public health concerns or illusions of control over unruly technology question the extent to which we can ‘really’ shape the world around us. Human-made crises, too, test how we routinely do things. We ask how organisations and actors within them prepare for a collapse of meaning and practise radical uncertainty. Given the breadth and depth of the region’s energy (and, as some would argue, turbulences), Asia provides a fitting context for exploring accommodation to and learning from low-probability, high-impact incidents. By reviewing the business and management research on shocks in Asia, we find that there is a strong human side to dealing with the unknown. We argue that what organisations and actors within them do prior, during and after a shock event is substantially contingent upon cultural environments. To elaborate, we discuss the role of the uncertainty avoidance dimension of national culture in dealing with shock events. We further combine this dimension with the universalism-particularism dimension to discuss future research directions. Our exploration of resultant differences in preparedness, resourcefulness and learning offers a more rounded inquiry into how Asian business actors deal with shocks.

Martensitic steels are widely used in the automotive lightweight application but less understood in aspects of post-forming material properties. The steels show good ductility in roll forming but occasionally experience delayed (hydrogen) fracture issues, which are believed to be due to the formation of localized residual stress and a reduced product of strength and elongation. To characterize the effect of roll forming process on the formation of residual stress and material properties variation of martensitic steel components, this paper investigates the forming-induced longitudinal residual stress and material property variation in a roll-formed high-strength MS1180 automotive rocker panel. The finite element analysis results for residual stress are validated by neutron diffraction measurements. The numerical model is used to analyze the full evolution of residual stress during the roll forming process and the effect on material properties with major focus on the product of strength and elongation. It is found that the flower design, in particular the overbending stages, play a significant role in the formation of residual stress and the change in material properties. The product of strength and elongation is significantly reduced across the profile, in particular in the corners. The achieved understanding will assist researchers comprehend the material properties of roll-formed component and therefore assist future studies aimed at preventing the occurrence of hydrogen fracture.

The objective of this study is to examine the association between neighborhood socioeconomic status (nSES) and baseline allostatic load (AL) and clinical trial endpoints in patients enrolled in the E1A11 therapeutic trial in multiple myeloma (MM). Study endpoints were symptom burden (pain, fatigue, and bother) at baseline and 5.5 months, non-completion of induction therapy, overall survival (OS) and progression-free survival (PFS). Multivariable logistic and Cox regression examined associations between nSES, AL and patient outcomes. A 1-unit increase in baseline AL was associated with greater odds of high fatigue at baseline (adjusted OR [95% CI] = 1.21 [1.08–1.36]) and a worse OS (adjusted hazard ratio, [95% CI] = 1.21 [1.06–1.37]). High nSES was associated with worse baseline bother (middle OR = 4.22 [1.11–16.09] and high 4.49 [1.16–17.43]) compared to low nSES. There was no association between AL or nSES and symptom burden at 5.5 months, non-completion of induction therapy or PFS. Additionally, there was no association between nSES and OS. AL may have utility as a predictive marker for OS among patients with MM and may allow individualization of treatment. Future studies should standardize and validate AL patients with MM.

The present study examines the bending behavior of coarse and fine-grained AZ31 magnesium alloy. The corresponding deformation mechanisms are ascertained via tensile, compression, and bending tests in combination with digital image correlation and electron backscatter diffraction. It is shown that grain refinement from 60 μm to 3 μm significantly improves tensile ductility, while forming limits in compression and bending show no obvious effect of grain size. Analysis of the microstructure revealed a high density of twin bands in the compression zones of the bent samples. Interestingly, the fine-grained material experienced failure in the compression zone. The fracture strain in bending appears limited by the material ductility in both tension and compression. The outcome of this study is that in magnesium alloys grain refinement may not always be an effective method for the improvement of ductility, particularly when bending of the type considered here is dominant.

Team personal-life inclusion (Team PLI) refers to socialization with fellow team members in the private domain. While PLI is an expected behavior in the socially oriented Chinese work context, it is generally seen as unfavorable in task-oriented contexts like Germany. We investigate the relative impact of Team PLI on the performance of Chinese and German teams. Based on data from 130 Chinese and 124 German teams, we show that Team PLI has opposing consequences in China and Germany. While it increases German teams’ performance, the reverse relationship was observed for Chinese teams.

An aluminium foam sandwich (AFS) material was formed by V-die bending and roll forming. The V-bent sections showed material failure by shear fracture of the aluminium foam core and by delamination at the core-cover sheet interface. This led to a high-gull wing defect and a limited section depth that could be formed. In contrast, the roll forming process allowed the manufacture of long sections with acceptable profile depth. Only minor gull wing was observed, and this was related to a low-shear deformation of the aluminium foam core and an intact adhesion at the core-cover sheet interface. The higher material formability observed in roll forming compared to that in V-die bending was attributed to a more evenly distributed contact pressure and more homogeneous forming, due to the incremental nature of the process, combined with a continuous contact of the metal sheet with the top and bottom rolls. Some forming problems were also observed in the roll-formed AFS components, but overall, the results of this study suggest that roll forming represents a good alternative to bending or stamping for the forming of longitudinal components of simple cross section shape that are of interest to the transport, solar or housing industries.

A study of preferable deformation modes on strain path and strain level in a TWIP steel sheet was performed. Different strain paths were obtained by stretch forming of specimens with various shapes and tensile tests. TEM analysis was performed on samples cut from various locations in the deformed specimens, which had different strain paths and strain levels and the preferable deformation modes were identified. Stresses caused by various strain paths were considered and an analytical analysis performed to identify the preferable deformation modes for the case of single crystal. For a single crystal, in assumption of the absence of lattice rotation, the strain path and the level of accumulated equivalent strain define the preferable deformation mode. For a polycrystalline material, such analytical analysis is not possible due to the large number of grains and, therefore, numerical simulation was employed. For the polycrystalline material, the role of strain path diminishes due to the presence of a large number of grains with random orientations and the effect of accumulated strain becomes dominant. However, at small strains the strain path still defines the level of twinning activity. TEM analysis experimentally confirmed that various deformation modes lead to different deformation strengthening mechanisms.

The elastic recovery in dual-phase (DP) steels is not a linear process and changes with plastic deformation. The level of change in the apparent Young’s modulus has been reported to depend on material composition and microstructure, but most previous experimental studies were limited to industrial DP steels and led to contradicting results. This work represents a first fundamental study that investigates the separate and combined effect of phase volume fraction and hardness on the change in apparent Young’s modulus in DP steel. A common automotive DP steel (DP780) is heat treated to obtain seven different combinations of martensite and ferrite volume fraction and hardness while keeping the chemical composition as well as the shape of the martensite and ferrite phases unchanged. Loading-unloading tests were performed to analyze the chord modulus at various levels of pre-strain. The results suggest that the point of saturation of the chord modulus with pre-strain depends on the morphology of the microstructure, occurring earlier for microstructures consisting of ferrite grains surrounded by martensite laths. It is further revealed that the reduction of the apparent Young’s modulus, which is the difference between the material’s initial Young’s modulus and the chord modulus, increases with martensite hardness if the martensite volume fraction is kept constant. A higher martensite volume fraction initially elevates the reduction of the apparent Young’s modulus. After a critical volume fraction of martensite phase of 35%, a decrease in apparent Young’s modulus reduction was observed. A comparison of the plastic unloading strain suggests that the mechanisms leading to a reduction in apparent Young’s modulus are strongest for the microstructure consisting of 35% martensite volume fraction.

Roll forming has been used traditionally in the construction and housing industry for the production of longitudinal components but is now increasingly applied in the automotive industry for the manufacture of structural and crash components from ultra high-strength steel (UHSS); the incremental nature of this process allows these hard-to-form materials to be shaped with higher efficiency and less shape defects than observed in common sheet forming processes such as stamping. Tight dimensional tolerances are imposed on automotive components, and this can lead to problems when roll forming UHSS where the high material strength results in shape defect and forming problems. Recent work has therefore increasingly focused on developing process monitoring and control routines for roll forming to improve process robustness and part quality. In roll forming, the longitudinal edge strain is considered to be related to product defects such as bow, twist and end flare. Process and part shape parameters have been shown to significantly influence peak longitudinal edge strain, and the link between process and product parameters, longitudinal edge strain and shape defects needs to be understood for the roll forming of UHSS if routines for process monitoring and control are to be established. Previous studies were mainly focused on traditional roll forming materials used for building products and the like. In this paper, the effect of process and part shape parameters on the peak longitudinal edge strain, longitudinal bow and springback is experimentally and statistically investigated for three different advanced high-strength steel (AHSS) and UHSS commonly used in automotive manufacturing. The results show that there are significant differences in behaviour when forming UHSS and that forming trends differ from those reported for softer steel grades. The experimental data presented in this paper should contribute to the further development of advanced process monitoring and part shape quality control routines in the roll forming AHSS and UHSS.

In roll forming a wide flat channel, problems were experienced with wrinkling, or ‘oil canning’ in the web. This is a common shape problem in roll forming wide panels that have flat regions in the profile. Coils from four different suppliers were used in production; with three of these, wrinkling could be controlled, but one coil had to be discarded. Tensile tests performed on all materials did not identify major differences in the coils although one material showed a slight indication of ageing. Free bending tests were performed with a new stand-alone bend tester specifically developed for material characterisation on the shop floor. The bending tests performed on strips cut in the longitudinal direction showed a greater difference between coils; the material giving unacceptable wrinkling had a significantly higher moment curvature characteristic indicating substantial ageing. All materials showed some coil set and the bending properties depended on the direction in which the specimen was bent, i.e. in the same or opposite direction to the coil set. A finite element analysis was performed on the process which indicated significant plastic deformation in the flange, but very little in the web. Possible links between the unusual bending behaviour and oil canning in the web are suggested and the work indicates the desirability of performing free bending tests in addition to the customary tensile testing in roll forming applications.

In a previous paper, a simple model was developed to extend the application of the traditional flower pattern diagram as a design tool for roll forming. The position of a point on the strip as it passes through each set of rolls can be identified as a series of points in the two-dimensional flower pattern diagram. In three dimensions, these points will lie on a non-circular cylindrical surface having its axis parallel to the machine axis. Assuming that these points are joined by a smooth curve, the forming path of a point on the strip as it passes through the roll forming process can be obtained as a plane curve on the plane development of this surface. It was shown in previous work that the longitudinal membrane strain and, in certain cases, local curvature of the sheet are functions of the slope of this plane curve. In this work, the strains on both surfaces at the edge of a strip in the forming of a simple V-channel are measured using strain gauges. It is shown that near the point of contact with the rolls, the strains differ by nearly an order of magnitude from those determined from the simple model which assumes that the trajectory is a smooth curve. A modification of the forming path is obtained from the measured bending strains. Although the changes in displacement are small, the peak values of strain near the point of roll contact are large and a consequence of highly localised changes in the forming path as the strip passes over each roll. Measurement of this perturbation in the forming path is difficult as the region is obscured by the forming rolls. The technique described here permits the reconstruction of this path and identifies a new area of investigation of longitudinal strains in roll forming. These are often associated with shape defects such as bow, warping and end flare.

Roll forming is a continuous process in which a flat strip is incrementally bent to a desired profile. This process is increasingly used in automotive industry to form High Strength Steel (HSS) and Advanced High Strength Steel (AHSS) for structural components. Because of the large variety of applications of roll forming in the industry, Finite Element Analysis (FEA) is increasingly employed for roll forming process design. Formability and springback are two major concerns in the roll forming AHSS materials. Previous studies have shown that the elastic modulus (Young’s modulus) of AHSS materials can change when the material undergoes plastic deformation and the main goal of this study is to investigate the effect of a change in elastic modulus during forming on springback in roll forming. FEA has been applied for the roll forming simulation of a V-section using material data determined by experimental loading-unloading tests performed on mild, XF400, and DP780 steel. The results show that the reduction of the elastic modulus with pre-strain significantly influences springback in the roll forming of high strength steel while its effect is less when a softer steel is formed.

The development of ultra/advanced high strength steels (U/AHSS) has challenged traditional forming methods due to their higher strength and reduced formability. An alternative method is flexible roll forming, which allows the manufacture of sheet metal of high strength and limited ductility into complex and weight-optimized components. However, one major problem in flexible roll forming is the web-warping defect, which is the deviation in height of the web over the length of the profile. The authors’ previous work developed an analytical model to predict the magnitude of web-warping. That model was purely geometric and neglected the effect of material properties. This work develops an analytical solution for the prediction of web-warping that considers both geometric and material parameters. The model results were validated by comparison with numerical and experimental results. The impact of this new model will be the ability to provide a rapid initial design assessment before an intensive numerical analysis of flexible roll forming is conducted.

The nonlinear unloading behavior of three different commercial dual-phase steels (DP780 grade equivalent) was examined. These steels exhibited small variations in chemical composition (0.07 to 0.10 mass percent carbon) and martensite volume fraction (0.23 to 0.28), and they demonstrated similar hardening behavior. Uniaxial loading-unloading-loading tests were conducted at room temperature and quasi-static strain rates between engineering strains of 0.5 and 8%. Steel microstructures were examined using electron backscatter diffraction and nanoindentation techniques. The microplastic component of the unloading strain exhibited no dependence on the martensite volume fraction or the ferrite grain size within the small range encountered in this investigations. Instead, the magnitude of the microplastic component of the unloading strain increased as the strength ratio between the martensite and ferrite phases increased. Correspondingly, the apparent unloading modulus, or chord modulus, exhibited a greater reduction for equivalent increments of strain hardening as the strength ratio increased. These results suggest that springback can be reduced in structures containing two ductile phases if the strength ratio between the harder and softer phases is reduced.

The initial process design of a roll forming system is often based on the traditional ‘flower pattern diagram’. In this diagram, the cross sections of the strip at each roll stand are superimposed on a single plane; the diagram is a 2D representation of the 3D process. In the present work, the flower pattern is extended into three dimensions. To demonstrate the method, the forming path or trajectory of a point at the edge of the strip during forming a V-section is considered. The forming path is a surface curve that lies on a cylindrical surface having its axis along the machine axis. This surface is unwrapped to give its plane development and important features of the forming process can be determined and are readily interpreted from this plane curve. It is shown that at any stage in the process, the axial strain and the curvature of the sheet adjacent to the point are dependent on the slope of the trajectory in this plane projection. This new diagram, which apparently has not been used previously, provides a useful initial method of examining the roll forming process and optimising the flower pattern. The model is purely geometric, as is the original flower pattern approach, and does not include the effect of material behaviour. The concept is applied to several cases available in the literature. It shows that the lowest level of shape defect in the part is achieved when the trajectory of the strip edge follows the shortest line length between the start and finish of forming, leading to the least longitudinal strain introduced in the flange. This trend is in agreement with previous experimental observations, suggesting that the analytical model proposed may be applied for early process design and optimisation before time-consuming numerical analysis is performed.

The roll forming process is increasingly used in the automotive industry for the manufacture of structural and crash components from Ultra High Strength Steel (UHSS). Due to the high strength of UHSS (

We investigated how treatment-induced neuropathic symptoms are associated with patients' quality of life (QOL) and clinician-reported difficulty in caring for patients.Data were obtained from 3,106 outpatients with colorectal, breast, lung, or prostate cancer on numbness/tingling (N/T), neuropathic pain, and QOL. Clinicians reported the degree of difficulty in caring for patients' physical and psychological symptoms.For all patients, moderate to severe N/T was associated with poor QOL (OR = 1.82, 95% CI = 1.47-2.26, P 0.001) but neuropathic pain was not (OR = 1.31, 95% CI = 0.94-1.83, P = 0.114). Moderate to severe N/T and neuropathic pain were associated with increased care difficulty (OR = 1.49, 95% CI = 1.27-1.74, P 0.001 for N/T, and OR = 1.46, 95% CI = 1.15-1.84, P = 0.002 for neuropathic pain). The association of neuropathic pain with care difficulty was most significant in patients with colorectal cancer (CRC) (OR = 2.32, 95% CI = 1.41-3.83, P = 0.001). Baseline neuropathic pain was associated with declining QOL in CRC patients (OR = 2.08, 95% CI = 1.21-3.58, P = 0.008).Clinicians may experience increased care difficulty for patients of all cancer types with moderate to severe N/T or neuropathic pain; care difficulty due to neuropathic pain may be higher for CRC patients. Nearly half the patients of all cancer types with moderate to severe N/T may expect poor short-term QOL; CRC-but not other-patients with baseline neuropathic pain are likely to experience declining QOL.About half of patients with moderate to severe N/T (any cancer type) may expect poor QOL in the short term; CRC patients with baseline neuropathic pain in particular may experience declining QOL.

Chemotherapy-induced peripheral neuropathy is frequently a dose-limiting factor in cancer treatment and may cause pain and irreversible function loss in cancer survivors. We tested whether alpha-lipoic acid (ALA) could decrease the severity of peripheral neuropathy symptoms in patients undergoing platinum-based chemotherapy. Cancer patients 18 years or older were randomly selected to receive either 600 mg ALA or a placebo three times a day orally for 24 weeks while receiving chemotherapy regimens including cisplatin or oxaliplatin. Neuropathy was measured by the Functional Assessment of Cancer Therapy/Gynecologic Oncology Group-Neurotoxicity (FACT/GOG-Ntx) scale and the NCI Common Toxicity Criteria for Adverse Events neurotoxicity grades. Results from timed functional tests and the Brief Pain Inventory (BPI) were secondary endpoints. Seventy of 243 (29 %) patients completed the study (24 weeks). Both the ALA and the placebo arms had a comparable drop-out rate. No statistically significant differences were found between the ALA and the placebo groups for FACT/GOG-Ntx scores, BPI scores, and patients' functional outcomes. This strategy of oral ALA administration was ineffective at preventing neurotoxicity caused by oxaliplatin or cisplatin. High attrition rates due to poor patient compliance and manner of dosage administration in this trial demonstrated a lack of feasibility for this intervention. Future studies to explore ALA as a neuroprotective agent should take heed of the barriers confronted in this study.

In the original article K. Mester’s first name is incorrect. It is correct as reflected here.

Generalizing a classic result by Polya concerning the zeros of successive derivatives of meromorphic functions in the complex plane, we study the accumulation set of zeros of successive derivatives of automorphic functions in the hyperbolic plane, as well as the connection between the automorphism group and the topology of this set in the Poincare disk model.