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Public health equalization has a significant impact on residents’ health and economic growth. Recently, studies suggested the persistence of series of public health unequal issues in China, such as imbalanced government financial investment, unreasonable configuration of public health resources, etc. The healthcare system in Jiangsu province is a microcosm of the pattern of healthcare delivery in China. Identifying developmental differences in Jiangsu and consequential effect on healthcare output can serve as a good reference for comparing performance of healthcare facilities within China in general. Based on the Model of Health the Healthy Production from Grossman and Lucas’ New Endogenous Economic Growth Model, we selected data from China Statistical Yearbooks and Jiangsu Statistical Yearbooks. 13 cities in Jiangsu province were divided into three groups, categorized as economically developed areas, relatively economically developed areas and less-economically developed areas. The panel cointegration model and e PVECM PVECM error correction model based on E-G two-step method are utilized for empirical research. During the period of 2006–2015, there were differences between the short term effect and long term effect on regional development resulted by the public health equalization level of Jiangsu Province. In the short term, the healthcare investment equalization level has been improved, to a certain extent, which executes a certain promoting effect on the people’s health development and regional economic growth in the long term, which restraint the improvement and development of long term public health equalization level and stimulating on the residents’ health and economic growth. The government of China in general and Jiangsu province in particular could ensure the efficiency of public health human resources, reform the public hospital internal system and establish an effective competition system, aiming to improve the public health equalization and promote balanced development of residents’ health and economic growth.

Recent advances in the field of digital technology have enabled the expansion of the business market to a new level. Digital business markets encompass eminent features like increased transparency, enhanced customer relationship, flexible business targets, customer participation, etc. It aids in enhancing traditional business quality by bridging the relationship between the suppliers and the customers. The massive development of internet technology in recent years has largely contributed to the emergence of digital business. The digitization of the business world helps small and medium enterprises create a new digital network, which allows overcoming large enterprises' dominance. Since small and medium enterprises play a major role in determining a country's economy, the digital market's emergence and development are very important. The self-organizing capability of the digital market is the main advantage for newly emerging enterprises. Recently, the Covid-19 pandemic has resulted in customers' migration from offline shopping to the online market. These changing business models mandate the need for policies and control mechanisms. Using these policies, digital business projects are developed using an open environment using which the small and medium enterprises can interact with each other. These policies and control mechanisms outline the rules to be followed to avoid the current digital market issues. These policies must be designed to improve and ensure the welfare of future digital business systems. Thus, this paper aims to explore the policies associated with regulating and promoting the digital business economy.

Graphene with a large tensile strain is a promising candidate for the new "straintronics'' applications. The current approaches of strain engineering on graphene are mainly realized by flexible or hollow substrates. In this work, a novel method for strained graphene on a rigid substrate assisted by PDMS stretching and interface adjustments is proposed. The Raman spectra show that the maximum strain of graphene on the SiO

A NiH-catalyzed migratory hydroalkylation of alkenyl amines with predictable and switchable regioselectivity is reported. By utilizing a ligand-controlled, directing group-assisted strategy, various alkyl units are site-selectively installed at inert sp

Voice and face are two most popular biometrics for person verification, usually used in speaker verification and face verification tasks. It has already been observed that simply combining the information from these two modalities can lead to a more powerful and robust person verification system. In this article, to fully explore the multi-modal learning strategies for person verification, we proposed three types of audio-visual deep neural network (AVN), including feature level AVN (AVN-F), embedding level AVN (AVN-E), and embedding level combination with joint learning AVN (AVN-J). To further enhance the system robustness in real noisy conditions where not both modalities can be accessed with high-quality, we proposed several data augmentation strategies for each proposed AVN: A feature-level multi-modal data augmentation is proposed for AVN-F and an embedding-level data augmentation with novel noise distribution matching is designed for AVN-E. For AVN-J, both the feature and embedding level multi-modal data augmentation methods can be applied. All the proposed models are trained on the VoxCeleb2 dev dataset and evaluated on the standard VoxCeleb1 dataset, and the best system achieves 0.558, 0.441% and 0.793% EER on the three official trial lists of VoxCeleb1, which is to our knowledge the best published single system results on this corpus for person verification. To validate the robustness of the proposed approaches, a noisy evaluation set based on the VoxCeleb1 is constructed, and experimental results show that the proposed system can significantly boost the system robustness and still show promising performance under this noisy scenario.

Drug development based on target proteins has been a successful approach in recent decades. A conventional structure-based drug design pipeline is a complex, human-engineered pipeline with multiple independently optimized steps. Advances in end-to-end differentiable learning suggest the potential benefits of similarly reformulating drug design. Here, we proposed a new sequence-to-drug paradigm that discovers drug-like small-molecule modulators directly from protein sequences and validated this concept for the first time in three stages. First, we designed TransformerCPI2.0 as a core tool for the sequence-to-drug paradigm, which exhibited competitive performance with conventional structure-based drug design approaches. Second, we validated the binding knowledge that TransformerCPI2.0 has learned. Third, we applied a sequence-to-drug paradigm to discover new hits for E3 ubiquitin-protein ligases: speckle-type POZ protein (SPOP), ring finger protein 130 (RNF130) which does not have a 3D structure, and repurposed proton pump inhibitors (PPIs) for ADP-ribosylation factor 1 (ARF1). This first proof of concept shows that the sequence-to-drug paradigm is a promising direction for drug development.

The independent expertise required by the preparation and application of graphene has brought a challenge to the more fluent development of graphene devices. We combine the advantages of chemical vapor deposition and micromechanical exfoliation methods of synthesizing graphene to develop a "graphene tape" for the fast utilization of graphene, which is robust, storable, and user-friendly. Prepared by pretransferring graphene to the surface of a polymer carrier film with weak interfacial adhesion, this graphene tape enables the acquisition, patterning, and layer-by-layer epitaxy of scalable graphene on a target substrate through simple cutting, pressing, and peeling off. Multiple characterizations demonstrate its comparable quality with as-synthesized graphene even after stored for over 30 days, overcoming the time and space limitations of acquiring a graphene sample. We believe that this graphene tape can bridge the current gap between graphene synthesis and applications and promote industrial progress of graphene-based devices in the post-Moore era.

The neurovascular unit (NVU) reflects the close temporal and spatial link between neurons and blood vessels. However, the understanding of the NVU in the spinal cord is far from clear and largely based on generalized knowledge obtained from the brain. Herein, we review the present knowledge of the NVU and highlight candidate approaches to investigate the NVU, particularly focusing on the spinal cord. Several unique features maintain the highly regulated microenvironment in the NVU. Autoregulation and neurovascular coupling ensure regional blood flow meets the metabolic demand according to the blood supply or local neural activation. The blood–central nervous system barrier partitions the circulating blood from neural parenchyma and facilitates the selective exchange of substances. Furthermore, we discuss spinal cord injury (SCI) as a common injury from the perspective of NVU dysfunction. Hopefully, this review will help expand the understanding of the NVU in the spinal cord and inspire new insights into SCI.

This paper presents the SJTU system for both text-dependent and text-independent tasks in short-duration speaker verification (SdSV) challenge 2021. In this challenge, we explored different strong embedding extractors to extract robust speaker embedding. For text-independent task, language-dependent adaptive snorm is explored to improve the system performance under the cross-lingual verification condition. For text-dependent task, we mainly focus on the in-domain fine-tuning strategies based on the model pre-trained on large-scale out-of-domain data. In order to improve the distinction between different speakers uttering the same phrase, we proposed several novel phrase-aware fine-tuning strategies and phrase-aware neural PLDA. With such strategies, the system performance is further improved. Finally, we fused the scores of different systems, and our fusion systems achieved 0.0473 in Task1 (rank 3) and 0.0581 in Task2 (rank 8) on the primary evaluation metric., Comment: Published by Interspeech 2021

In vascular interventional surgery, surgeons operate guidewires and catheters to diagnose and treat patients with the assistance of the digital subtraction angiography (DSA). Therefore, the surgeon will be exposed to X-rays for extended periods. To protect the surgeon, the development of a robot-assisted surgical system is of great significance. The displacement tracking accuracy is the most important issue to be considered in the development of the system. In this study, the active disturbance rejection control (ADRC) method is applied to guarantee displacement tracking accuracy. First, the core contents of the proportional–integral–derivative (PID) and ADRC methods are analyzed. Second, comparative evaluation experiments for incremental PID and ADRC methods are presented. The results show that the ADRC method has better performance of than that of the incremental PID method. Finally, the calibration experiments for the ADRC control method are implemented using the master–slave robotic system. These experiments demonstrate that the maximum tracking error is 0.87 mm using the ADRC method, effectively guaranteeing surgical safety.

Submerged floating tunnels (SFTs) are a novel type of traffic structure for crossing long straits or deep lakes. To investigate the dynamic pressure acting on an SFT under compression (P) wave incidence, a theoretical analysis model considering the effect of marine sediment is proposed. Based on displacement potential functions, the reflection and refraction coefficients of P-waves in different media are derived. Numerical examples are employed to illustrate the effects of the thickness of the sediment layer, the incident P-wave angle, the tether stiffness and spacing, and the permeability of the sediment on the dynamic pressure loading on the SFT. The results show that the dynamic pressure is related to the saturation of the sediment and affected by its thickness. Partially saturated sediment will amplify the dynamic pressure loading on the SFT, and the resonance frequency increases slightly with fully saturated sediment. Besides, increasing the tether stiffness or decreasing the tether spacing will decrease the dynamic pressure. Locating the SFT at greater depth and reducing the permeability of the sediment are effective measures to reduce the dynamic pressure acting on the SFT.

The virtual training system of vascular interventional surgery can improve the operation level of novice interventional surgeons and reduce the training cost. The deformation simulation of vascular tissue is the key part of the virtual training system for vascular interventional surgery. This paper presents a vascular tissue model based on nonlinear viscoelastic tensor-mass method (NVTMM), which can realize real-time visual feedback and haptic feedback. The hyperelastic model is used to simulate the nonlinear viscoelastic behavior of blood vessels. Meanwhile, the Euler's implicit integration scheme is used to make the simulation results more stable. In addition, a haptic force feedback device is introduced for the interaction between the vascular model and the virtual medical instrument, which improves the authenticity of the simulation. Finally, the real-time performance and accuracy of NVTMM, MSM and FEM are compared through experiments. The results show that NVTMM method has high real-time performance and can reflect the nonlinear viscoelastic behavior of blood vessels to a certain extent.

In the master-slave vascular interventional robot system, visual feedback can help surgeons to make better decisions about the surgical operation. A novel intraoperative information monitor system is developed based on the QT development platform. In this system, the numerical value and the curve are combined to display the collision force information of the slave manipulator, the displacement information with the errors of the master manipulator and slave manipulator and the video image of the camera in slave side. Meanwhile, through the color-changeable image to make surgeons more intuitive understanding of the changeable operation force, and then to assist surgeons to operate more smoothly, this system can also record the operation data of different surgeons, which lays a foundation for the research of the recognition and intelligent navigation of surgeon's operation. Finally, the effectiveness of the system is verified by the information communication experiments with the slave robot.

With the increasing use of vascular interventions, catheter navigation in complex vessels has become even more critical. Vascular intervention surgeries also require more precise manipulation and a more intelligent system to ensure the safety of the patients. In this paper, a virtual training model based on deep reinforcement learning was designed to navigate the catheter into the aortic arch. The whole experiment was carried out in a virtual environment, and a reinforcement learning method was used to test the performance of catheter autonomous navigation in vessels. Finally, the model was successfully trained and results were analyzed basing on previous work. The results obtained would be more convincing if the model was more complex and closer to the actual vessels.

According to the report of the National Cancer Center, there are about 4.5 million new cancer patients and 3 million deaths in China every year. How to effectively implement a comprehensive system of prevention and control measures and reduce the incidence rate of malignant tumors in the country, so that the mortality rate of cancer is effectively controlled is a problem that needs to be solved urgently. In particular, it is worth mentioning that in China, the addition of traditional Chinese medicine in the treatment of malignant tumor plays an important role in improving the therapeutic effect, reducing the toxic and side effects of comprehensive treatment, improving the quality of life, and "survival with tumor" of end-stage cancer patients. Professor Wang Xisheng has been engaged in the field of traditional Chinese medicine in the treatment of cancer for more than 40 years. In his long-term clinical practice, he has accumulated rich experience in the prevention and treatment of malignant tumors. This article introduces Professor Wang's thinking on cancer in clinical practice and the "Fu Yuan Fu Heng method" in the treatment of malignant tumors for reference.

Data augmentation (DA) is an effective strategy to help building robust systems with good generalization ability. In the embedding based speaker verification, data augmentation could be applied to either the front-end embedding extractor or the back-end PLDA. Unlike the conventional back-end augmentation method which adds noises to the raw audios and then extracts augmented embeddings, in this work, we proposed a noise distribution matching (NDM) based algorithm in the speaker embedding space. The basic idea is to use distributions such as Gaussian to model the difference between the clean and original augmented noisy speaker embeddings. Experiments are carried out on SRE16 dataset, where consistent performance improvement could be obtained by the novel NDM. Furthermore, we found that the proposed NDM could be robustly estimated using only a small amount of training data, which saves time and disk cost compared to the conventional augmentation method.

Submerged floating tunnel (SFT) is a novel type of cross-sea traffic structure, which is different from the traditional bridge and immersed tunnel. With the help of its own buoyancy to balance the operational loads, SFT shows great potential for crossing long, large, and deep waterways. Since floating in the underwater environment all year around, SFT has to face a series of vibration problems during the operation. In this paper, some vibration problems of SFT, such as wave-induced vibration, vortex-induced vibration, vibration caused by accidental loading, and vehicle-induced vibration, are summarized. In the meantime, combined with the features of SFT, the test model is designed and manufactured in the work. The geometric scale ratio of the whole model is about 1:100. Some aluminum tubes, connected by the flanges, are used for simulating the main body of SFT. Two plexiglass boxes provide the platform for the model test car to move in the aluminum tubes. The cable force, displacement, and acceleration at the points in the control sections of the tube are monitored during the model test. The whole experimental work provides a meaningful reference and solid foundation for further study on vibration problems of SFT.

At present, vascular intervention technique is the most effective way to treat cardio-cerebrovascular diseases. Vascular interventional surgical robot is applied to assist surgeons to done surgical operation effectively, and the study on this kind of robot is become a research hotspot. In vascular interventional surgery, surgeons mainly judge the state of catheter and guide wire in the blood vessel through vision and touch. Therefore, accurate force feedback is helpful for surgeons to operate interventional surgery better. However, most interventional surgery robots focus on the realization of axial force feedback and few robot systems can accurately feedback the circumferential force of the guidewire and the catheter. In this paper, a clamping mechanism for circumferential force feedback device is designed and calibrated. Firstly, the clamping mechanism is designed based on the friction theory and the control method of this mechanism is described in details. Secondly, the calibration methods of the clamping mechanism are proposed. Lastly, the calibration of the mechanism is verified by experiments, and the mechanism is optimized by analyzing the experimental results. The experimental results show that the mechanism can provide an accurate clamping force for the circumferential force feedback device.

Based on the recent research, the force feedback equipment with non-contact displacement measure device is helpful and valuable, which can reduce the size and increase flexibility of master manipulator largely, and so on. In this paper, a novel axil force feedback device with non-contact displacement measure equipment is designed. Firstly, the design theory based on electromagnetics and the working principle are elaborated in detail. Secondly, the calibration experiment of non-contact displacement measure equipment is done, which is used to build the relationship between the displacement and the pixel values. Lastly, Motion interference of moving parts are analyzed simply, and the experiments are done to verify the performance of displacement measurement. By analyzing the experimental results, this axial force feedback device is helpful and valuable for miniaturization of the master manipulator.

Using deep neural network to extract speaker embedding has significantly improved the speaker verification task. However, such embeddings are still vulnerable to channel variability. Previous works have used adversarial training to suppress channel information to extract channel-invariant embedding and achieved a significant improvement. Inspired by the successful joint multi-task and adversarial training with phonetic information for phonetic-invariant speaker embedding learning, in this paper, a similar methodology is developed to suppress the channel variability. By treating the recording devices or environments as the channel variability, two individual experiments are carried out, and consistent performance improvement is observed in both cases. The best performance is obtained by sequentially applying multi-task training at the statistics pooling layer and adversarial training at the embedding layer, achieving 10.77% and 9.37% relative improvements in terms of EER compared to the baselines, for the recording environments or devices level, respectively.

In this paper, we have demonstrated the high hole mobility in accumulation-mode Ge-on-insulator (AM-GeOI) pMOSFETs with back interface engineering by low-temperature H2 annealing. The hole mobility of 227 cm2 V−1 s−1 was obtained for the device annealed at 400 °C in H2 ambient, which is 32% higher than that of the control device. A significant improvement in carrier mobility was attributed to two main factors: (1) the atomic rearrangement of Si and Ge in the intermixing layer located at the back interface, and (2) partial relaxation of tensile strain by thermal treatment.

To analyze the dynamic behavior of a submerged floating tunnel (SFT) subjected to moving vehicle loads in an ocean current environment, a theoretical analysis model is proposed. The SFT is simplified as a beam on an elastic foundation, the moving vehicle is modeled as a spring-mass lump, and the current effect is considered as a combination of lift force, inertial force, and hydraulic resistance directly acting on the SFT. The governing equations are solved by the modal superposition method. A finite element method is developed to evaluate the results. The impact effects of the vertical displacement and the bending moment are used to analyze the dynamic responses of the SFT. The effects of some key parameters, such as the current velocity, the buoyancy-weight ratio (BWR), and the inclined angle of the tethers are also investigated. The results show that the behaviors of the structure are amplified under the fluid-vehicle-tunnel interaction. Furthermore, the current and the vehicle velocity will directly affect the impact responses of the SFT by changing the forces on the structure. The BWR and the inclined angle of the tethers will change the vibration characteristics of the SFT and affect the inside state of the structure.

Klebsiella variicola B16, a microbial bioflocculant (MBF-B16)-producing bacteria, was isolated and identified by its 16S rRNA sequence, biochemical properties, and physiological characteristics. The effects of culture conditions on MBF-B16 production, including carbon source, nitrogen source, C/N ratio, initial pH, and culture temperature, were investigated in this study. Results showed that 6.96 g of MBF-B16 could be extracted from a 1-L culture broth under optimized conditions. Chemical analysis showed that polysaccharide and protein were the main components. The neutral sugar consisted of galactose only, which was proposed in Klebsiella genus for the first time. In addition, a composite flocculant (CF) that contains polyaluminum ferric chloride (PAFC) and MBF-B16 for the removal of turbidity and SS in drinking water was optimized by response surface methodology. CF could reduce PAFC dosage by about 56.2–72%. Charge neutralization and adsorption bridging effect were the primary flocculation mechanisms.

Purpose Early pubertal onset may relate to more involvement in bullying in adolescent girls, both as a target and as a perpetrator. However, the few studies of the association between early menarche and school bullying have shown mixed findings. The present study examined whether early menarche is associated with bullying victimization and perpetration. Methods We obtained survey data on adolescent girls from the 2001–2002, 2005–2006, and 2009–2010 cycles of the Health Behaviour in School-aged Children study in 35 European and North American countries. We identified school bullying in the past 2 months using the Revised Olweus Bully/Victim Questionnaire. We defined early menarche as a reported onset of menarche before 11 years and tested the associations between early menarche and bullying victimization and perpetration using three-level logistic regression models. Results The sample included 227,443 adolescent girls with a mean age of 13.64 (standard deviation [SD] 1.63) years, of which 10,172 (4.47%) were early matured; 62,528 (28.33%) and 56,582 (25.67%) were occasional victims and perpetrators, respectively; and 21,985 (9.96%) and 14,115 (6.40%) were frequent victims and perpetrators, respectively. Early menarche related to occasional victimization (adjusted odds ratio [OR] [95% confidence interval [CI] = 1.21 [1.12–1.31]) and perpetration (aOR [95% CI] = 1.19 [1.11–1.27]) and to frequent victimization (aOR [95% CI] = 1.35 [1.22–1.50]) and perpetration (aOR [95% CI] = 1.46 [1.31–1.63]). Conclusions Early menarche in European and North American adolescent girls positively relates to bullying victimization and perpetration. Early-maturing girls should not be neglected in antibullying programs.

An innovative approach involving chemical modification of the surface of MgO nanoparticles (NPs) for steelmaking and application of NPs to carbon structural steel has been investigated. The results show that the inclusions in the test steels were completely converted to MgAl2O4 spinel or MnS complex inclusions. The mean inclusion size decreased with increasing NP content from 0.01% to 0.03%, but increased at 0.05% because of NP aggregation. Addition of NPs increased the amount of intragranular ferrite and prevented polygonal ferrite formation, thereby enhancing the impact toughness. Impact tests showed that the dimple fractures in steel with 0.05% NP content were deeper than those in the other samples because the MgAl2O4 inclusions were larger. The surface-modified MgO NPs had a major effect on the inclusion characteristics and microstructure of carbon structural steel.

Anchor-cables are critical bearing components of the submerged floating tunnel (SFT). As the accidental cable-breakage incident will seriously threaten the public safety, this paper investigates the global dynamic response of a SFT subjected to an abrupt anchor-cable failure by focusing on the post-breakage behavior. Firstly, an approximate theoretical approach is proposed, in which the analysis model of SFT is simplified and the alternate load path method (AP method) is adopted to simulate the cable-breakage process. Then, the differential equations of the SFT tube are established based on the Hamilton principle, and solved through the fourth order Runge-Kutta method. A finite element analysis in ABAQUS is also performed as a verification of the theoretical results, in which the VUSDFLD subroutine and ABAQUS/Aqua is employed to simulate the stiffness loss of the cable and apply the fluid loads respectively. A good agreement exists between the simplified theoretical model and FE simulation. Finally, the effects of some key parameters are discussed, such as the gravity-buoyance ratio and the damping ratio of the SFT, the breakage time and position of the broken cable, etc. The results show that the structural vibration is intensive after the sudden cable breakage. Also, the remaining anchor-cables close to the cable-loss position are most affected by the cable rupture. The change of gravity-buoyance ratio and damping ratio have notable effects on structural deformation. The SFT is most unfavorable when the cable breakage happens at the mid-span or near the two ends of the tunnel. The vibration amplitude attenuates significantly with the increase of the failure time of anchor-cable.

We propose an oxygen scavenging technique based on thermodynamic considerations of metal and oxygen systems to stabilize the ferroelectric phase and enhance the ferroelectricity in Hf-based oxides. By using an oxygen scavenging metal to control the oxygen vacancy concentration in Hf-based oxides, the effect of this oxygen scavenging technique in ferroelectric Hf-based oxides was systematically investigated. It was revealed that controlling the oxygen vacancies during the crystallization process is of vital importance to stabilizing the ferroelectric properties. This oxygen scavenging technique is an effective method of improving the performance of Hf-based ferroelectric materials without employing any dopant in Hf-based oxides.

We investigate the effects of U.S. monetary policy shocks from alternative policy indicators for a modern sample encompassing 1988–2020. The choice of the Wu and Xia (2016) shadow federal funds rate leads to persistent price puzzles. These puzzles arise despite inclusion of the usual suspect fixes such as commodity prices, federal funds futures and forward rate data. We find they occur at monthly and quarterly frequencies. We consider alternative indicators with the same broad monetary aggregates Keating et al. (2019) employed in their investigation of a historical sample. They provide a consistent resolution of the price puzzle and they do not require the ad hoc inclusion of commodity prices or futures data. This price puzzle correction is not a feature of our time-varying approach as it also obtains from constant parameter econometric estimation. Our analysis suggests monetary policy has transmitted substantial expansionary effects in money markets in the aftermath of the 2007 Financial Crisis and the decade that followed.

To investigate the dynamic behavior of the submerged floating tunnel (SFT) under moving vehicle load, a SFT experimental model is designed and analyzed. Through typical experiment cases, the effects of cable and vehicle with different parameters on the SFTs are discussed. Besides, the numerical simulation method is proposed in ABAQUS/EXPLICIT module for contrastive analysis. The *VUMAP and the *VDLOAD subroutines are used for implementing the tube fluid force and the moving vehicle load in the numerical model. The results show that the vertical vibration of the SFT is relatively independent to other directions, and the connection between the tubes will partially weaken the overall stiffness of the SFT. In addition, the deviation amplification effect exists in the SFT subjected to moving vehicle load. Increasing the cable inclination angle and the cable diameter can reduce the amplification effect. For the SFT with different cable spacing, the deviation amplification effect of dense cable arrangement is smaller than that of the sparse cable arrangement. But their sensitivities to vehicle velocity are not very different. In the practical project, the cables should provide sufficient strength to the SFT for safety.

A quadratic yield function which can describe the anisotropic behaviors of sheet metals with tension/compression symmetry and asymmetry is proposed. Five mechanical properties are adopted to determine the coefficients of each part of the yield function. For particular cases, the proposed yield function can be simplified to Mises or Hill's quadratic yield function. The anisotropic mechanical properties are expressed by defining an angle between the current normalized principal stress space and the reference direction with the assumption of orthotropic anisotropy. The accuracy of the proposed yield function in describing the anisotropy under tension and compression is demonstrated.