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Cindy Sherman, a female post-modern artists, experiments with multiple identities in her artworks to disclose issues related to gender power structures, such as male gaze, voyeurism, and flawed aesthetic pursuits forced by males, and to promote positive female images, scraping off stereotypes of women being emotional, brainless, and dependent. Though she alludes to twentieth-century Holleywood B movies, fashion posters, and fairy tales, the humor and sarcasm used in her work and the groundbreaking feminism ideas altogether leads Cindy Shermans portrait photographs beyond a superfacial use of pastiche, a technique of blank mimicry that Fredric Jameson believes most postmodernists employ. Cindy Sherman achieves a complication in her topics through choices of props and settings, wearing makeups, and employing gestures.

The advantages of well-distributed material flow, easy demolding, and good mechanical interlock structure of the extensible die provide the possibility to be widely used in joining lightweight components. In order to explore the differences in the mechanical properties of the joints produced by different dies, the mechanical behavior of the clinched joints made by the fixed die and extensible dies of 2, 3, and 4 movable segments was investigated in the present study. The process of forming evolution, geometric characterization, failure mode, static strength, joint stiffness, and energy absorption of the dissimilar joints were studied by experimental method. In the clinching process, the neck thickness of joints made by extensible dies can be enlarged by the sliding outward of the movable segments compared with those produced by fixed dies. The failure mode of all clinched joints in this paper is neck fracture. The clinched joints produced by extensible dies of 3 movable segments have the highest static strength in both static tensile and shear tests among the dissimilar joints, which values are 1239.41 and 1259.80 N, respectively. Shearing strength of the joints performed by the extensible dies with 2, 3, and 4 movable segments was increased by 9.84%, 10.09%, and 9.40%, and the tensile strength of those clinched joints was increased by 16.27%, 20.31%, and 14.34% than that of the joints produced by the fixed dies. Experimental have proved that the number of movable segments on the extensible dies has a limited effect on the joint stiffness, tensile strength, and energy absorption of the clinched joints in the cross-lap-tensile test, while it has great effect on the stiffness and energy absorption of the clinched joints in the single-lap-shear test.

Flat clinched joints are increasingly being investigated due to the flat bottom surface. In the current study, the shape of the flat clinching tools was optimized to improve the joint strength. Experimental tests of flat clinching were carried out using different forming loads to provide validation data for finite element simulations. Cross-tension tests were conducted under quasi-static conditions to evaluate the mechanical characteristics of the joint samples. Multiple finite element models based on the response surface method were developed to obtain the functional relationship between the four tool parameters and neck area, as well as the functional relationship between the four parameters and undercut area, respectively. The geometric effects of the flat clinching tools on the neck and undercut areas were analyzed. A genetic algorithm was used to obtain a solution set that maximized both the neck and undercut areas. The cross-tension strength of the joint produced according to the best-tested solution was 1526 N, which was 13.7% higher than that of the pre-optimized joint. The optimization method in this study could effectively improve the joint strength of the flat clinching process.

Mechanical clinching technology, with the ability to join dissimilar, coated, and hard-to-weld materials, has been widely adopted in the automotive field. The finite element method has been proved to be an efficient and effective approach for investigating the clinching process. This paper comprehensively overviewed the recent advances in the application of finite element methods on the clinching process. The modeling methodologies of clinching process, such as material modeling, meshing operation, and contact definition, were summarized and discussed. The advances regarding finite element method used in various types of clinching processes were also reviewed respectively. Subsequently, the finite element methods used to conduct parameter study and strength prediction in the clinching process were introduced and reviewed. Finally, some outlooks about FEM used in the clinching process were proposed and discussed.

Increasing attention has been paid to the flat clinching process for constructing advanced engineering structures because it has more benefits than the conventional cliching process. The effect of material arrangements on flat clinching process was investigated in the paper. The four material arrangements using three dissimilar aluminum alloys were employed to develop flat clinching joints. The cross-sectional profile of the joint was observed, and its main geometrical parameters were determined. The mechanical characteristics of the joint include four parts: tensile strength, shearing strength, failure mode, and absorbed energy. Tension-shearing and tensile tests were carried out to assess the mechanical characteristics of the flat clinching joint. The geometric profile and the material properties determine the mechanical characteristics of the flat clinching joint. Compared with the flat clinching joint using a hard lower sheet, the flat clinching joint with a hard upper sheet demonstrates a larger neck thickness and a lower undercut. Meanwhile, it has greater static strength and absorbed energy. In tension-shearing tests, necking failure is only failure mode appearing; in tensile tests, failure mode mostly belongs to unbutton failure. The flat clinching process can effectively join dissimilar aluminum alloy sheets.

The current study is conducted to analyze the influence of thickness configurations on the mechanical properties of the flat-clinching joint. Al1060-H12 sheets with four-type thickness configurations were employed in flat-clinching process. Pull-out and single-lap shear tests were implemented to obtain the static strengths and absorbed energies of the clinching joints. Their main geometrical parameters and failure modes were also discussed and studied. The clinching joint with a thick top sheet achieves smaller undercut and greater neck thickness than the joint using a thick bottom sheet. Compared with the clinching joint using a thick bottom sheet, the joint with a thick top sheet has larger absorbed energy and static strength in single-lap shear tests. In pull-out tests, absorbed energy and static strength of the joint using a thick bottom sheet are larger than the joint with a thick top sheet. Flat-clinching process can reliably join Al1060-H12 sheets with different thickness configurations.

The flat clinching process is attracting a growing attention in the joining field of lightweight materials because it avoids the geometric protrusion that appears in the conventional clinching process. In this paper, the effects of sheet thickness and material on the mechanical properties of the clinched joint were studied. Al1060 and Al2024 sheets with 2 mm thickness were employed to develop the clinched joint by using different material configurations, and Al1060 sheets with 2.5- and 1.5-mm thicknesses were used to produce the clinched joint by using different thickness configurations. The clinched joints using various sheet configurations were sectioned, and dimensional analysis was conducted. Cross-tensile and shearing tests were carried out to analyze the mechanical properties of the clinched joint, including tensile strength, shearing strength, and absorbed energy. In addition, the failure modes of the clinched joints were discussed. Results indicated that the clinched joint with a stiff top sheet had increased static strength regardless of the test type. The clinched joint with a thick top sheet demonstrated lower static strength than the joint with a thick bottom sheet in the cross-tensile test. However, this result was reversed in the shearing tests. The flat clinching process has a great potential in joining dissimilar and various thickness materials.

In order to reduce the protrusion height and increase the strength of the clinched joint, a two-step clinching method was investigated in the present study. The whole process contains two steps. The first step is used to produce one-step clinched joints, and the second step is used to press the one-step clinched joints to reduce the protrusion height and increase the joining strength. The influences of clinching steps and sheet thicknesses on the mechanical properties of the clinched joint were investigated. The main failure mode of all the clinched joints in the strength tests is the neck fracture mode. The neck thickness can be enlarged by the two-step clinching method, and the protrusion height can be reduced. TCJ2.5-2.0 joint has the highest energy absorption and strength, and OCJ2.0-2.5 joint has the lowest energy absorption and strength. The two-step clinching process can contribute to increasing energy absorption and joining strength. For getting higher strength, the thick sheet should be taken as the top sheet. With higher strength and lower protrusion, the use of two-step clinched joint will be convenient in the mechanical engineering areas.

Glass and metal have wide applications in various industries due to their excellent properties. To make the most use of their properties and enlarge their applications, it is important to bond the glass and metal. Many bonding methods of glass and metal in recent years are reviewed in this article. The advantages and deficiencies of different bonding methods are discussed. The main problems between glass and metal in bonding process are proposed, and some suggestions to solve these problems are introduced. Finally, the development direction of bonding methods for glass and metal in the future is discussed.

Clinching technology has been widely applied in automobile assembly industries to join sheet materials of different thicknesses and properties. It does not require any auxiliary parts and only depends on the plastic deformation of materials themselves to form a joint. Furthermore, clinching tools that include the punch and the die are simpler than other thermal joining methods. However, the usability of the clinched joint is restricted by a low joining strength. In order to expand the application range of clinching technologies, researchers have conducted extensive researches on how to improve clinching technologies. In this article, the latest advances of clinching technologies are reviewed on the development of clinching tools and processes. The improved clinching processes including flat clinching, hole clinching, reshaping the clinched joint without a rivet, reshaped joint with a rivet, rivet clinching, rectangular clinching, dieless clinching, roller clinching, laser shock clinching, hydro-clinching, injection clinching, adhesive clinching, resistance spot clinching, friction-assisted clinching, and laser-assisted clinching are introduced. The advantages and disadvantages of different clinching technologies are proposed. In addition, some suggestions for the future development of clinching technology are given in this paper. The clinching technology is developing towards a hybrid joining technology with high strength, high stability, and high efficiency.

In this article, we consider the near-Hamiltonian system where a < 0, 0 < |e| << 1, f (x, y) and g(x, y) are polynomials of degree n ( n = 2 m , m ≥ 3, m ∈ N ). The number of isolated zeros of the ...

To improve the cruising range and mobility of EVs, various traction batteries (TBs) have been studied and widely used in China. The operation of EVs is difficult because of the reduction in the capacity resulting from the low temperature. A computer model of an electric vehicle power battery is proposed in this paper to study the effect of temperature on battery performance parameters. The variation of EV battery parameters (voltage, current, capacity) with temperature will be discussed, The change of EV battery parameters (voltage, current, capacity) with temperature will be discussed. Experiments at different temperatures have been constructed to verify the accuracy of the model.

Organometallic sandwich complexes have been attracting tremendous interest for their potential applications in electronics and spintronics. Here, we systematically studied the structures, electronic and magnetic properties of one dimensional (1D) transition metal (TM)-anthracene (Ant) sandwich molecular wires (SMWs), [TM2Ant]∞ and [TM3Ant]∞ (TM=Ti, V, Cr, Mn), based on density functional theory calculations. Our results showed that all the 1D SMWs display normal sandwich configurations with their binding energies closely related to the choice of TM atoms. Excepting 1D [Mn2Ant]∞ and [Fe3Ant]∞ favoring antiferromagnetic ordering, most 1D [TM2Ant]∞ and [TM3Ant]∞ SMWs display robust ferromagnetic feathers. Particularly, 1D [Cr3Ant]∞ SMW is revealed to be ferromagnetic half-metal with large magnetic moment of 28.0µB per unit cell. Further spintransport calculations double proved that 1D [Cr3Ant]∞ SMW are good spintransport molecular devices. Our findings shed light on the properties of 1D Ant based SMWs and propose a new way to design potential electronic and spintronic devices.

The purpose of this study was to evaluate the neuroprotective effect of leptin on a non-human primate model of cerebral ischemia. A total of 39 Guangxi macaques were used to establish the primate cerebral-ischemia model. HE staining was used to evaluated the pathological changes. Moreover, magnetic resonance imaging was used for the detection of embolic area. The measurements of behavior observation and cerebral infarction area were also performed. They all received autologous thrombus operation. Furthermore, western blot and RT-PCR were also used to detect the protein and mRNA expression levels of apoptosis-related factors. Our results showed that leptin could reduce the volume of cerebral infarction by about 35%. Behavioral defects can be significantly improved. In addition, mid-term and long-term behavioral deficiencies had been significantly improved by leptin. Moreover, leptin significantly decreased the expression levels of caspase-3 and Bax, and increased the expression levels of Bcl-2. In conclusion, leptin has neuroprotective effects on cerebral ischemia by effectively reducing the volume of cerebral infarction.

We present a simple-structured strain sensor based on a low-cost ionic liquid. The ionic liquid was made of sodium chloride/propylene glycol solution and was embedded in a linear microfluidic channel fabricated using Ecoflex. The proposed sensor is capable of measuring strain up to 100% with excellent repeatability. The highest gauge factor is obtained as 6.19 under direct current excitation and 3.40 under alternating current excitation at 1 kHz. The sensor shows negligible hysteresis and overshoot, and survived 10,000 rapid stretch-release cycles of a 100% peak strain with a minor deviation in the response signal. The sensor can be mounted to different locations on the human body and suits a variety of applications in the field of motion detection, human–machine interface and healthcare monitoring.

City-scale traffic speed prediction provides significant data foundation for the intelligent transportation system, which enriches commuters with up-to-date information about traffic condition. However, predicting on-road vehicle speed accurately is challenging, as the speed of the vehicle on the urban road is affected by various types of factors. These factors can be categorized into three main aspects, which are temporal, spatial, and other latent information. In this paper, we propose a novel spatio-temporal model named L-U-Net based on U-Net as well as long short-term memory architecture and develop an effective speed prediction model, which is capable of forecasting city-scale traffic conditions. It is worth noting that our model can avoid the high complexity and uncertainty of subjective features extraction and can be easily extended to solve other spatio-temporal prediction problems such as flow prediction. The experimental results demonstrate that the prediction model we proposed can forecast urban traffic speed effectively.

In recent years, the mechanical clinching method plays an increasingly important role in the building of thin-walled structures. The clinched joint can be employed to join the lightweight materials. Compared with other joining methods, the clinched joint has better mechanical behavior. However, the clinched joint may be deformed during use when it bears a high shear force. In this research, a process to join aluminum alloy and restore deformed joint was proposed and investigated. The clinched joint was deformed in the deforming process. Then, a customized rivet and two flat restoring tools were utilized for restoring the deformed joint to join aluminum alloy. Different restoring forces such as 45, 40, 35, 30, 25, and 20 kN were employed to produce diverse restored joints. Some shearing tests on the restored joint were utilized for understanding joint material flow, mode of failure, thickness of neck, shear strength, and absorption of energy. The thickness of neck can be increased in restoring process, which contributes to improve the shear strength. The rivet embedded in a pit also helps restored joint bear shear force, so all of the restored joints have higher absorption of energy and shear strength than the clinched joints. The restoring process effectively restores the deformed joint to obtain better mechanical behavior.

In this paper, we investigate the global existence and uniqueness of a periodic wave solution of the generalized Burgers–Fisher equation. We prove that the generalized Burgers–Fisher equation admits an isolated periodic wave solution based on the monotonicity of the ratio of two Abelian integrals.

Clinching technology is widely used in the connection of lightweight materials. However, the conventional clinching with a round punch performs poorly in connecting thick sheets and hard sheets. In the present study, the clinching process with rectangle punch is investigated by the experimental method. The clinching process with rectangle punch can join the sheets by cutting sheets and generating an interlock. Al5052 sheets were joined using the rectangle punch with different forming forces. The forming process, shear strength, tensile strength, and failure mode were analyzed. The result shows that the shear strength is higher than the tensile strength of the joint generated with the same forming force. The forming force of 25 kN is proved to be the best forming force to join the Al5052 sheet with a thickness of 1.8 mm. The average tensile strength and shear strength of the joint are 1052 N and 1585 N respectively.

With the increasing popularity of mobile phones, constructing user profile from the usage of mobile phone becomes a critical research interest. Previously, the key of these researches was the improvement of the accuracy of user profiling algorithms. However, most of algorithms are hard to achieve theoretical optimum under practical scenario due to the limited performance of consumer-grade terminal. A common solution is to upload raw user data to cloud server and analyze them on the cloud-side, which leads to the huge consumption of cloud computing resources. In this paper, we propose a framework for obtaining user profile based on collaboration between smart terminal devices and cloud servers. The framework divides the computational flow of the user profiling algorithm into two parts, which will be executed on the phone and on the server respectively. The framework reduces the amount of resources consumed on users' phones, while avoiding uploading too much data to the cloud servers. This paper introduces the principle and structure of the framework. Finally, the framework is compared with a terminal-side frame which perform user profile calculations only using terminal devices and a cloud frame obtaining user profile only using cloud servers.

For years, behavior understanding has been a hot topic in the field of computer vision. As an important part of human behavior understanding, pose estimation has attracted lots of interests. Recently, deep learning methods, such as Mask R-CNN, have achieved much better performance for computer vision tasks than that of traditional approaches, as deep neural network can find representative features efficiently. For pose estimation, most of the deep learning approaches mainly focus on the joint feature. However, this feature is not sufficient, especially when the pose is occluded or not intact. In fact, many features other than joint can also contribute to pose estimation, such as body boundary, body orientation and visibility condition. By adopting multi-task strategy, these features can be efficiently combined inside deep learning model for pose estimation. In this paper, we present a multi-task pose estimation approach to deal with human behavior understanding. Our deep learning model is based on Mask-RCNN, of which the output contains 4 tasks: human keypoint prediction, body segmentation, orientation prediction and mutual occlusion detection. Our model is trained on the public dataset COCO, which is further augmented by ground truths of orientation mask and occlusion mask. Experiments show the learning accuracy of the proposed method. Comparisons further illustrate the performance improvement after combining more features by multi-task strategy.

The flat-clinching is attracting increasing attentions in the field of lightweight structures because it does not form an exterior protrusion on the bottom sheet like the conventional clinching. In the present research, the flat-clinching process for joining the three-layer sheets is investigated through experimental methods. Sheet specimens were divided into two types based on loading characteristics and employed to produce joint specimens with different sheet configurations. The effects of the sheet configurations on the mechanical characteristics of the clinched joint were analyzed. This study consisted of five parts: the evolution of the forming force, main geometrical parameters, failure modes, static strength, and absorbed energy. The results show that five parameters can be employed to assess the joining reliability, where the neck thickness of the first interlock and the interlock width of the second interlock perform essential roles in the static strength and failure modes of the joint. In the static strength tests, the joint sample, in which the bottom sheet is clamped on its own while the middle and upper sheets are clamped together, exhibits higher static strength and absorbed energy than the joint sample where the upper sheet is clamped on its own while the middle and bottom sheets are clamped together. In addition, the joint specimens with different sheet configurations have different failure modes. The flat-clinching can join three-layer sheets by two interlocks to create a thin-walled structure.

Recently, lightweight materials have been increasingly used to build engineering structures, especially automotive structures. Mechanical clinching, an advanced joining technology, is widely used to join lightweight materials on the structures. The clinched joint may be deformed or damaged when it bears higher shearing forces. Till now, there is no effective repairing technology to repair deformed/damaged clinching joints. A novel repairing process is thus proposed and studied in this paper. A custom-built rivet and two flat dies were used as main repairing tools. Different damaging forces were applied on clinched joints to produce different damaged joints. The damaging force, cross-sectional profile, neck thickness, and shearing force of the repaired joints were investigated. The novel process is suitable to repair deformed/damaged clinching joints. As for the deformed joint, the deformed neck can be reshaped to restore to its original shape in the repairing process. As for the damaged joint, the separated sheets are hooked by a new interlock generated by the custom-built rivet. Compared with clinched joint, the repaired joint can get higher shear strength, which is significant for the safety of engineering structures.

The clinched joint may be deformed or damaged under a high shear load on the thin-walled structure, which may cause an accident. In order to avoid the accident, a renovating process for the deformed and damaged joint was proposed and investigated in this paper. The clinched joints were gotten by clinching equipment in clinching process. Shear process was employed to produce deformed and damaged joints with different shear forces. Then the deformed and damaged joints were renovated under a force of 35 kN with two flat dies and a customized rivet. Through static shear test on the renovated joints, the failure mode, shear strength and energy absorption were obtained. Renovating force, failure mode, main geometrical parameters, cross-sectional profile, shear strength, and energy absorption were discussed on renovated joints. The energy absorption and shear strength of all the joints are increased after the renovating process. It has been verified to be available for this process to renovate the deformed and damaged joint.

Apriori is the most famous frequent pattern mining method. It scans dataset repeatedly and generate item sets by bottom-top approach. In order to reduce time complexity, we proposed a modified algorithm named as Frequent Matrix Apriori (FMA). Firstly, FMA scans the dataset only once to store frequent item information in a frequent matrix. Then, FMA discretize the matrix by the minimum support parameter which is generated automatically. Thirdly, it scans the discretized frequent matrix and find the most frequent item sets recursively. Experimental results proved that FMA is more effective than Apriori on time consuming with similar accuracy.