Search

In this paper, the chain structure of magnetorheological fluid (MRF) magnetic particles was studied and analyzed, the mechanical model of MRF with different diameter ferromagnetic particles was established, silicone oil-based MRF with different particle volume fractions was prepared, the shear properties of the MRF were tested, and the theoretical and experimental data were compared. The experimental results show that the shear stress is stable with the increase of shear strain rate under the action of the magnetic field, and it has a shear thinning effect. The shear stress increases linearly with the increase of particle volume fraction. The shear stress increases with the increase of magnetic induction intensity. After data analysis and in the case of control variables, the average error of improved theoretical data and experimental data is lower than that of previous theoretical data and experimental data, which verifies that the improved theory (mechanical model) has a certain accuracy.

A new catalyst (Fe2(SO4)3-NaCl) was employed for the selective conversion of corncob hemicellulose to xylose via hydrothermal treatment. The optimal conditions included Fe2(SO4)3-NaCl treatment for 2 h at 140 °C to achieve the selective conversion of hemicellulose (92.4 wt%) and a xylose yield of 106.8 wt%, which is based on the hemicellulose content in corncobs. These conditions led to a cellulose and lignin dissolution of 7.9 and 21.2 wt%, respectively. Fe2(SO4)3 was found to play an important role, rather than NaCl, in the disruption of interactions among the three major components, while the conversion of lignin and cellulose was inhibited by NaCl and Fe2(SO4)3, respectively. The co-addition of Fe2(SO4)3 and NaCl promoted the selective dissolution of hemicellulose, leaving most of the cellulose and lignin unreacted in the solid residue. Additionally, Fe2(SO4)3 inhibited the formation of formic and acetic acids. A second hydrothermal treatment on the hemicellulose-free residue with the same catalytic system at 140 °C for 2 h resulted in 42.2 wt% cellulose conversion and a fructose yield of 79.7 wt% based on converted cellulose. Therefore, a potential route for the comprehensive utilization of corncobs is proposed.

Additional file 1. Supplementary materials for the prediction and prognosis of adverse maternal and foetal/neonatal outcomes in pulmonary hypertension.

Person re-identification refers to matching people across non-overlapping camera views on different locations and at different times. In the case of changes in perspective, light, background, veil, and person's clothing, traditional method cannot achieve person recognition effectively and reliably. In this paper, we propose a novel biometric metric learning method named Human Skeleton Mutual Learning person re-identification (HSMLP-Reid). The purpose of HSML person re-identification method (HSMLP-Reid) largely aims to use the new pedestrian local segmentation method proposed in this paper combined with the global skeleton information to solve the influence of background and local posture change. Firstly, bottom-up method is used to estimate the pedestrian posture and skeleton and the joint points of the pedestrians will be marked in this process. A new local segmentation method proposed in this paper named joint segmentation is used to locally segment pedestrians and perform local block matching. Furthermore, we learn the global skeleton information by defined joint distances from the pedestrian 2D skeleton estimation by the bottom-up method and use global skeleton information to global skeleton matching. Finally, we use local match and global skeleton match for mutual learning. Local match based on pedestrian nodes and global skeleton match based on pedestrian skeleton are based on biometrics. We learn the classification loss and metric learning loss to train model. Metric loss includes global skeletal distance and local block metric distance. Extensive experimental results on the large-scale Market1501, CUHK03 and CUHK-SYSU data sets demonstrate that the proposed method achieves consistently superior performance and outperforms most of the state-of-the-art methods.

In this paper, according to the discipline characteristic of the course of intelligent transportation system, we discussed on the problems existing in the teaching of vehicles related majors. The reform methods of the course is discussed in two aspects of teaching content and teaching method. Points out that the teaching content should be closer to the vehicles related majors; Teaching methods focus on interactive teaching, and cases should be throughout the classroom teaching; The classroom teaching and extracurricular learning should be combined, and practical teaching should be strengthen. We need to mobilize students' enthusiasm and creativity, in improving the efficiency of teaching and strengthen students' research interest in intelligent transportation system.

This paper is concerned with local H ∞ synchronization control of uncertain complex networks, in which there are nonlinear coupling functions between network nodes, and the coupling terms as well as network nodes are subject to time-varying delays. In order to make a complex network achieve H ∞ synchronization, a non-fragile state feedback control scheme is used. By employing the Lyapunov functional method, a sufficient condition on the existence of H ∞ non-fragile controllers is derived. This condition can not only guarantee the asymptotic stability of each network node, but also ensure a prescribed robust H ∞ performance level for the synchronization error system under study. The effectiveness of the proposed method is finally verified through a numerical example.

Tangguoa tongguling Yao & Li sp. nov. Figs 4���5 Type material. Holotype: male (IZCAS-Ar41643), Tongguling (19��40.303���N, 111��1.068���E, elevation 337 m), Longlou Town, Wenchang, Hainan, China, 22 March 2012, Z. Chen leg. Paratypes: 1 male (IZCAS-Ar41644) and 2 females (IZCAS-Ar41645���41646), same data as holotype. Etymology. The specific name refers to the type locality and is a noun in apposition. Diagnosis. This species can be easily distinguished from T. laibin sp. nov. by procursus with sclerotized, narrow and curved ventral apophysis (arrow 2 in Fig. 4C; absent in T. laibin sp. nov., Fig. 2C), wide, sclerotized dorsal apophysis with scales (arrow 4 in Fig. 4C; angular dorsal apophysis without scales in T. laibin sp. nov., arrow 3 in Fig. 2C), and retrolateral apophysis with scales and pointed sclerite (arrow 5 in Fig. 4C; two retrolateral processes without scales and sclerite in T. laibin sp. nov., arrows in Fig. 2D), by male chelicerae with frontal apophyses with scales (arrow in Fig. 5C; absent in T. laibin sp. nov., Fig. 3C), by external female genitalia with two postero-lateral apophyses (arrows 1���2 in Fig. 5A; absent in T. laibin sp. nov., Fig. 3A), by vulval pore plates anteriorly wide and posteriorly narrow and blunt (Fig. 5B; anteriorly wide and posteriorly sharply pointed in T. laibin sp. nov., Fig. 3B), and by opisthosoma with dorsal and lateral spots (Figs 5 E���H; with posterior marks in T. laibin sp. nov., Figs 3 E���H). Description. Male (holotype): Total length 2.03 (2.23 with clypeus), carapace 0.67 long, 0.96 wide, opisthosoma 1.36 long, 0.94 wide. Leg I: ��� (4.34 + 0.36 + 4.50 + 6.45 + ���), leg II: 10.42 (3.16 + 0.35 + 2.78 + 3.02 + 1.11), leg III: 8.48 (2.42 + 0.31 + 2.04 + 2.90 + 0.81), leg IV: 11.05 (3.28 + 0.33 + 2.73 + 3.93 + 0.78); tibia I L/d: 49. Distance PME-PME 0.16, diameter PME 0.11, distance PME-ALE 0.03, AME absent. Sternum slightly wider than long (0.58/0.48). Habitus as in Figs 5 E���F. Carapace yellowish, with brown margins and wide, brown median stripe; ocular area brown; clypeus yellowish, with brown lateral marks; sternum brown. Legs brownish, but slightly whitish on distal parts of femora and tibiae, with distinct darker rings on subdistal parts of femora and proximal and subdistal parts of tibiae. Opisthosoma yellowish, with large, brown, dorsal and lateral spots. Ocular area slightly elevated and separated from rest of carapace. Thoracic furrow shallow, but distinct. Chelicerae (Figs 5 C���D) with pair of proximo-lateral apophyses (arrow pa in Figs 5 C���D) with lateral apophyses and scales (arrow in Fig. 5D), pair of frontal apophyses with scales (arrow in Fig. 5C), and pair of distal apophyses with row of teeth each (arrow da in Figs 5 C���D). Pedipalps as in Figs 4 A���B; trochanter with retrolateral apophysis and ventral apophysis; femur strongly curved dorsally, with retrolateral apophysis; patella large; procursus simple proximally but complex distally, with sclerotized prolatero-ventral apophysis (arrow 1 in Fig. 4C), sclerotized, narrow and curved ventral apophysis (arrow 2 in Fig. 4C), sclerotized distal apophysis with scales (arrow 3 in Fig. 4C), wide, sclerotized dorsal apophysis with scales (arrow 4 in Fig. 4C), and retrolateral apophysis with scales and pointed sclerite (arrow 5 in Fig. 4C); bulb simple, without other projections except for embolus. Retrolateral trichobothrium of tibia I at 11% proximally; legs with short vertical setae on metatarsi and tarsi, without spines or curved setae. Female: Similar to male, habitus as in Figs 5 G���H. Total length 2.28 (2.43 with clypeus), carapace 0.79 long, 0.98 wide, opisthosoma 1.49 long, 1.06 wide; tibia I: 4.48; tibia I L/d: 49. Distance PME-PME 0.15, diameter PME 0.11, distance PME-ALE 0.03, AME absent. Sternum slightly wider than long (0.62/0.52). External female genitalia (Fig. 5A) brown, with postero-median apophysis (much longer than wide, arrow ma in Fig. 5A) provided with pointed tip and two pointed postero-lateral apophyses (arrows 1���2 in Fig. 5A), without pockets. Vulva (Fig. 5B) with curved anterior arch and pair of anteriorly wide and posteriorly narrow and blunt pore plates. Variation: Tibia I in male paratype: 4.52. Tibia I in another female paratype: 4.56. Natural history. The species was found in the leaf litter. Distribution. China (Hainan, type locality; Fig. 1)., Published as part of Yao, Zhiyuan, Luo, Yiping & Li, Shuqiang, 2021, Tangguoa gen. nov., one new genus of daddy-long-leg spiders (Araneae: Pholcidae) from southern China, pp. 131-140 in Zootaxa 4938 (1) on pages 136-139, DOI: 10.11646/zootaxa.4938.1.7, http://zenodo.org/record/4561477

Genus Tangguoa Yao & Li gen. nov. Type species: Tangguoa laibin Yao & Li sp. nov. Etymology. The generic name is dedicated to the late Chinese arachnologist Guo Tang. Gender is feminine. Diagnosis. This genus can be easily distinguished from Khorata Huber, 2005 and Savarna Huber, 2005 by male pedipalpal femur strongly curved dorsally (Figs 2 A���B, 4A���B; straight/slightly curved in Khorata and Savarna), by male chelicerae with distal apophyses medially (arrow da in Figs 3 C���D, 5C���D; with distal apophyses laterally in Khorata, without distal apophyses in Savarna) provided with row of teeth (without teeth in Khorata), and by external female genitalia with postero-median apophysis provided with pointed tip (arrow ma in Figs 3A, 5A; some species with postero-median lip in Khorata, without postero-median apophysis in Savarna); also distinguished from Khorata by male chelicerae without hooked frontal apophyses (Figs 3 C���D, 5C���D; with hooked frontal apophyses medially in Khorata). Description. Male: Total length 2.03���2.84 (2.23���3.03 with clypeus). Ocular triads relatively close together, distance PME-PME 0.16, diameter PME 0.10���0.11, distance PME-ALE 0.03, AME absent. Sternum wider than long. Carapace with brownish radiating marks and narrow, dark median line/brown margins and wide, brown median stripe; clypeus with brownish lateral marks; sternum brown (Figs 3 E���F, 5E���F). Legs with distinct darker rings on subdistal parts of femora and proximal/subdistal parts of tibiae. Opisthosoma with large, brown posterior marks/ large, brown, dorsal and lateral spots (Figs 3 E���F, 5E���F). Ocular area slightly elevated and separated from rest of carapace. Thoracic furrow shallow, but distinct (Figs 3E, 5E). Clypeus unmodified. Opisthosoma oval. Chelicerae with pair of proximo-lateral apophyses (arrow pa in Figs 3 C���D, 5C���D) with lateral apophyses and scales (arrow in Figs 3 C���D, 5D) and pair of distal apophyses with row of teeth (arrow da in Figs 3 C���D, 5C���D). Pedipalpal coxa unmodified; trochanter with retrolateral apophysis and ventral apophysis (both as wide as long; Figs 2 A���B, 4A���B); femur strongly curved dorsally, with retrolateral apophysis (Figs 2B, 4B); patella large; procursus complex distally, without hinged process (hinged process defined as figs 421, 432 in Huber 2011a); bulb simple, without other projections except for embolus (Figs 2 A���B, 4A���B). Leg formula 1>2>4>3 or 1>4>2>3; retrolateral trichobothrium of tibia I at 10���11% proximally; legs with vertical setae on tibiae, metatarsi and tarsi, without spines or curved setae; tarsus I with>15 distinct pseudosegments. Female: Similar to male, sexual dimorphism very slight. Legs slightly shorter. Chelicerae unmodified. External female genitalia brown, simple, with postero-median apophysis (arrow ma in Figs 3A, 5A) provided with pointed tip, without knob or pockets. Vulva (Figs 3B, 5B) with anterior arch and pair of pore plates. Natural history. Unknown, excepting the specific data of collection from specimens presented here. Distribution. China (Guangxi, Hainan; Fig. 1). Composition. T. laibin Yao & Li sp. nov. and T. tongguling Yao & Li sp. nov., Published as part of Yao, Zhiyuan, Luo, Yiping & Li, Shuqiang, 2021, Tangguoa gen. nov., one new genus of daddy-long-leg spiders (Araneae: Pholcidae) from southern China, pp. 131-140 in Zootaxa 4938 (1) on page 132, DOI: 10.11646/zootaxa.4938.1.7, http://zenodo.org/record/4561477, {"references":["Huber, B. A. (2005) Revision of the genus Spermophora Hentz in Southeast Asia and on the Pacific islands, with descriptions of three new genera (Araneae: Pholcidae). Zoologische Mededelingen, 79, 61 - 114.","Huber, B. A. (2011 a) Revision and cladistic analysis of Pholcus and closely related taxa (Araneae, Pholcidae). Bonner Zoologische Monographien, 58, 1 - 509."]}

Tangguoa laibin Yao & Li sp. nov. Figs 2���3 Type material. Holotype: male (IZCAS-Ar41631), Longn�� Cave (24��8.038���N, 109��57.596���E, elevation 143 m), Longn�� Mountain, Dale Town, Xiangzhou County, Laibin, Guangxi, China, 17 August 2009, Z. Yao and C. Wang leg. Paratypes: 6 males (IZCAS-Ar41632���41637) and 5 females (IZCAS-Ar41638���41642), same data as holotype. Etymology. The specific name refers to the type locality and is a noun in apposition. Diagnosis. This species can be easily distinguished from T. tongguling sp. nov. by procursus without sclerotized, narrow and curved ventral apophysis (Fig. 2C; present in T. tongguling sp. nov., arrow 2 in Fig. 4C), with angular dorsal apophysis (arrow 3 in Fig. 2C; wide, sclerotized dorsal apophysis with scales in T. tongguling sp. nov., arrow 4 in Fig. 4C) and two retrolateral processes (arrows in Fig. 2D; retrolateral apophysis with scales and pointed sclerite in T. tongguling sp. nov., arrow 5 in Fig. 4C), by male chelicerae without frontal apophyses (Fig. 3C; presence of frontal apophyses with scales in T. tongguling sp. nov., arrow in Fig. 5C), by external female genitalia without postero-lateral apophyses (Fig. 3A; presence of two postero-lateral apophyses in T. tongguling sp. nov., arrows 1���2 in Fig. 5A), by vulva with anteriorly wide and posteriorly sharply pointed pore plates (Fig. 3B; anteriorly wide and posteriorly narrow and blunt in T. tongguling sp. nov., Fig. 5B), and by opisthosoma with posterior marks (Figs 3 E���H; dorsal and lateral spots in T. tongguling sp. nov., Figs 5 E���H). Description. Male (holotype): Total length 2.84 (3.03 with clypeus), carapace 1.10 long, 1.26 wide, opisthosoma 1.74 long, 1.20 wide. Leg I: 27.85 (7.25 + 0.55 + 7.30 + 9.78 + 2.97), leg II: 19.70 (5.43 + 0.53 + 4.95 + 6.95 + 1.84), leg III: 15.38 (4.48 + 0.47 + 3.84 + 5.25 + 1.34), leg IV: 15.33 (4.47 + 0.47 + 3.80 + 5.28 + 1.31); tibia I L/d: 52. Distance PME-PME 0.16, diameter PME 0.10, distance PME-ALE 0.03, AME absent. Sternum wider than long (0.94/0.76). Habitus as in Figs 3 E���F. Carapace yellowish, with brownish radiating marks and narrow, dark median line; ocular area brownish; clypeus yellowish, with brownish lateral marks; sternum brown. Legs brownish, but slightly whitish on distal parts of femora and tibiae, with distinct darker rings on subdistal parts of femora and tibiae. Opisthosoma yellowish, with large, brown posterior marks. Ocular area slightly elevated and separated from rest of carapace. Thoracic furrow shallow, but distinct. Chelicerae (Figs 3 C���D) with pair of proximo-lateral apophyses (arrow pa in Figs 3 C���D) with lateral apophyses and scales (arrow in Figs 3 C���D) and pair of distal apophyses with row of teeth each (arrow da in Figs 3 C���D). Pedipalps as in Figs 2 A���B; trochanter with retrolateral apophysis and ventral apophysis; femur strongly curved dorsally, with retrolateral apophysis; patella large; procursus simple proximally but complex distally, with sclerotized prolatero-ventral apophysis (arrow 1 in Fig. 2C), sclerotized distal apophysis (arrow 2 in Fig. 2C), angular dorsal apophysis (arrow 3 in Fig. 2C), and two retrolateral processes (arrows in Fig. 2D); bulb simple, without other projections except for embolus. Retrolateral trichobothrium of tibia I at 10% proximally; legs with short vertical setae on tibiae, metatarsi and tarsi, without spines or curved setae; tarsus I with 16 distinct pseudosegments. Female: Similar to male, habitus as in Figs 3 G���H. Total length 3.44 (3.64 with clypeus), carapace 0.96 long, 1.16 wide, opisthosoma 2.48 long, 1.84 wide; tibia I: 6.76; tibia I L/d: 56. Distance PME-PME 0.15, diameter PME 0.11, distance PME-ALE 0.03, AME absent. Sternum wider than long (0.94/0.75). Carapace with brown margins. External female genitalia (Fig. 3A) brown, with nearly angular postero-median apophysis (arrow ma in Fig. 3A) provided with pointed tip, without pockets. Vulva (Fig. 3B) with curved anterior arch and pair of anteriorly wide and posteriorly sharply pointed pore plates. Variation: Tibia I in male paratypes (n = 6): 6.92���7.60 (mean: 7.28). Tibia I in the other female paratypes (n = 2, leg I missing in the other two specimens): 6.56, 6.94. Natural history. The species was found on the wall in the twilight zone (entrance ecotone) of the Longn�� Cave (karst area). Distribution. China (Guangxi, type locality; Fig. 1)., Published as part of Yao, Zhiyuan, Luo, Yiping & Li, Shuqiang, 2021, Tangguoa gen. nov., one new genus of daddy-long-leg spiders (Araneae: Pholcidae) from southern China, pp. 131-140 in Zootaxa 4938 (1) on pages 133-136, DOI: 10.11646/zootaxa.4938.1.7, http://zenodo.org/record/4561477

Genus Tangguoa Yao & Li gen. nov. Type species: Tangguoa laibin Yao & Li sp. nov. Etymology. The generic name is dedicated to the late Chinese arachnologist Guo Tang. Gender is feminine. Diagnosis. This genus can be easily distinguished from Khorata Huber, 2005 and Savarna Huber, 2005 by male pedipalpal femur strongly curved dorsally (Figs 2 A–B, 4A–B; straight/slightly curved in Khorata and Savarna), by male chelicerae with distal apophyses medially (arrow da in Figs 3 C–D, 5C–D; with distal apophyses laterally in Khorata, without distal apophyses in Savarna) provided with row of teeth (without teeth in Khorata), and by external female genitalia with postero-median apophysis provided with pointed tip (arrow ma in Figs 3A, 5A; some species with postero-median lip in Khorata, without postero-median apophysis in Savarna); also distinguished from Khorata by male chelicerae without hooked frontal apophyses (Figs 3 C–D, 5C–D; with hooked frontal apophyses medially in Khorata). Description. Male: Total length 2.03–2.84 (2.23–3.03 with clypeus). Ocular triads relatively close together, distance PME-PME 0.16, diameter PME 0.10–0.11, distance PME-ALE 0.03, AME absent. Sternum wider than long. Carapace with brownish radiating marks and narrow, dark median line/brown margins and wide, brown median stripe; clypeus with brownish lateral marks; sternum brown (Figs 3 E–F, 5E–F). Legs with distinct darker rings on subdistal parts of femora and proximal/subdistal parts of tibiae. Opisthosoma with large, brown posterior marks/ large, brown, dorsal and lateral spots (Figs 3 E–F, 5E–F). Ocular area slightly elevated and separated from rest of carapace. Thoracic furrow shallow, but distinct (Figs 3E, 5E). Clypeus unmodified. Opisthosoma oval. Chelicerae with pair of proximo-lateral apophyses (arrow pa in Figs 3 C–D, 5C–D) with lateral apophyses and scales (arrow in Figs 3 C–D, 5D) and pair of distal apophyses with row of teeth (arrow da in Figs 3 C–D, 5C–D). Pedipalpal coxa unmodified; trochanter with retrolateral apophysis and ventral apophysis (both as wide as long; Figs 2 A–B, 4A–B); femur strongly curved dorsally, with retrolateral apophysis (Figs 2B, 4B); patella large; procursus complex distally, without hinged process (hinged process defined as figs 421, 432 in Huber 2011a); bulb simple, without other projections except for embolus (Figs 2 A–B, 4A–B). Leg formula 1>2>4>3 or 1>4>2>3; retrolateral trichobothrium of tibia I at 10–11% proximally; legs with vertical setae on tibiae, metatarsi and tarsi, without spines or curved setae; tarsus I with>15 distinct pseudosegments. Female: Similar to male, sexual dimorphism very slight. Legs slightly shorter. Chelicerae unmodified. External female genitalia brown, simple, with postero-median apophysis (arrow ma in Figs 3A, 5A) provided with pointed tip, without knob or pockets. Vulva (Figs 3B, 5B) with anterior arch and pair of pore plates. Natural history. Unknown, excepting the specific data of collection from specimens presented here. Distribution. China (Guangxi, Hainan; Fig. 1). Composition. T. laibin Yao & Li sp. nov. and T. tongguling Yao & Li sp. nov.

This paper proposes a flexible line commutated converter (LCC) system with a cascaded H-bridge connected serially on the valve side of the converter transformer to solve the intrinsic commutation failure problem of the traditional LCC system. The proposed system can realize the decoupled control of the direct current (DC) bus voltage and the actual extinction angle through the LCC and the cascade H-bridge respectively. It can also improve low power factor issue of the traditional LCC system， which is analyzed and proved by the mathematical model of the flexible LCC system. Further, the coordinative control strategy fitting in with different grid conditions is presented and validated by the simulation model established in PSCAD/EMTDC. In comparison with the traditional LCC system, the proposed system demonstrates stronger ability to suppress commutation failure and maintain stability of DC bus voltage regardless of the depth of grid voltage dip. In addition, the proposed system will not increase the reactive power demand on the grid side during the fault time as the traditional LCC system. In contrast, it can offer reactive power support to the grid.

Yield stress is one of the main performance parameters of magnetorheological fluid (MRF). In order to satisfy the magnetic field requirement of yield stress test device, a magnetic circuit with current excitation is designed, and the finite element software is used to simulate the magnetic circuit. The test bench is built, and the magnetic field loading test is carried out. The magnetic induction intensity of the working gap of MRF is tested, and its B–I curve is obtained. Under the same current, there is a certain error between the magnetic induction intensity and the simulation result, and the maximum relative error is within 6%.

In order to research the rheological property of MRF at high shear rate, a magnetorheological fluid (MRF) rheological property testing device based on shear mode, is developed. The accurate analytical expressions of MRF rheological parameters in terms of structural dimensions of testing device and shear rate in the parallel plate gap are derived, and the flow state of MRF is considered, which provides the theoretical foundation for testing the rheological property of MRF at high shear rate. The relationship between magnetic indication in the parallel plate gap and excitation electrical current is experimentally obtained. Some elements influencing testing are analyzed and eliminated. The device is used to test the rheological parameters of MRF, and the results show that the yield stress of MRF increases significantly as the magnetic flux density continues to increase, and shear rate has no obvious effect on it. The shear rates in designed device may exceed 3 × 104 s−1, which meets the special demands in MRF testing.

According to the requirement of failure prediction and maintenance of high-precision machine tool spindle bearings, this article has designed a bearing fault prediction system using LabVIEW and database connection based on SPC theory. We collect the data of machined workpiece which are analyzed and processed based on SPC theory. And we set up a mathematical model so as to ensure the detection parameters and alarm thresholds. The system predicts the state of bearings through workpiece data. When the detection parameters exceed the threshold, the indicator will be triggered to alarm. The system has achieved the purpose of prediction.

Magnetorheological Fluids (MRFs) is rapidly emerging as a type of new fluid intelligence material that is controllable and low-energy consuming with high output and fast response. It has already received widespread attention from many international scholars. In this paper, the orthogonal test of MRFs configuration with six different types of lubricating additives (oleic acid, hydrogenated castor oil, teflon, boron nitride, molybdenum disulfide, graphite) is conducted to study the wettability, zero-field viscosity and yield stress of MRFs under different solid lubricants. According to the size of contact angle, the ability of anti-sedimentation stability of MRFs under different lubricants is compared. The zero-field viscosity of MRFs is tested by viscometer, and the strength of viscosity under the zero-field condition is compared. The yield stress is measured by a self-made yield stress device, and then the sedimentation stability characteristics of MRFs are analyzed. Finally, through the analysis and evaluation of experimental data, it is concluded that molybdenum disulfide as a lubricating additive can effectively improve the anti-sedimentation stability of MRFs, and the general rules of lubricating additives used in MRFs formulations with excellent performance are summarized.

With the technological development and awareness of energy conservation and environmental protection, how to take advantage of waste heat has been concerned global. However, effective methods to recycle low temperature waste heat which is lower than 200 °C are still lacked. A kind of pentabasic thermoelectricity system which is prepared by smelting and powder metallurgy method is described in this paper. Thermoelectric generator (TEG) modules with different area and height ratio (A/H) p-n couples are assembled. At temperature gradient 100 K, the TEG module can obtain the biggest load power 2.39 W corresponding the module with A/H = 5.5 and load resistance 1.5 Ω.

The Selective Catalytic Reduce (SCR) is studied. The unknown parameters of the SCR kinetic model equations are fitted based on the Genetic Algorithm (GA), which is in the range of the allowable error, compared to the experimental data. Then in AVL Boost software, the simulation results of SCR reaction are obtained. Compared to the test data, the simulation results prove that the parameter identification is effective. At last, the SCR reaction is simulated in AVL Boost, and at the same exhaust temperature, the effect of GHSV and NSR on the SCR reaction is studied.

This article introduces a mini EV for urban single drive, a the car intended to work as conveyance for city workers, thereby relieving urban traffic pressure, improving traffic congestion and reducing urban pollution. The paper primarily designs a electric reversed tricycle and determines its motor and battery parameters, fixes the cockpit installation location by ergonomics, and finally completes vehicle arrangement. CATIA is mainly used for modeling and ergonomics analysis during the design process.

High-precision machine tools are important equipment of production line in general (1). However, there has been more difficult on failure prediction and maintenance of its spindle bearings. There are no timely replacement of the bearing when the failure occurs will result in decreased equipment utilization. This paper designed a set of bearing failure prediction system based on LabVIEW programming environment aiming at the need of the maintenance of machine tool spindle bearing in production line. The system will predict the bearing failure through the analysis of the size precision of the parts machined by bearing. The system mainly consists of two parts, data acquisition system and data analysis system. It has functions of data analysis and calculation, data storage and display and alarms, etc.

In this paper, the lord magnetic field of MRF and its circuit design are mainly expounded, according to the loading ways of magnetic field and the magnetic circuit design plans of magneto-rheological fluid devices at present, the general form and characteristics are summarized. In addition, a kind of magneto-rheological fluid dynamometer is proposed in this paper, in terms of its magnetic circuit structure, a magnetic-field-lord test bench about magnetorheological fluid is designed; a preliminary theoretical research is also given in order to improve the performance of magneto-rheological fluid dynamometer.

The guaranteed cost synchronization control problem of some general complex dynamical networks with time delay is investigated. A dynamic feedback controller is designed for the system guaranteed cost synchronization. Meanwhile, due to many nodes in the complex networks and the complex of the direct control, use of the the pinning control to make the system achieve guaranteed cost synchronization is also investigated. Based on the Lyapunov stability theory and the matrix inequality, the sufficient conditions are obtained for the existence of the guaranteed cost controller with time delay in complex network. The dynamic feedback controller is designed to ensure the asymptotic stability conditions of the system and make the performance index of the system meet certain requirements. Finally, the feasibility of the proposed method is demonstrated by numerical examples.

To deal with complex disturbances and the presence of partial loss of propeller effectiveness in work-class remotely operated vehicles (ROVs), a method of robust fault tolerant control is proposed, which is based on adaptive sliding mode control. In this approach, adaptive technique is employed to estimate the bounds’ information of external complex disturbances and the effectiveness loss of the propeller. And a sliding mode controller is then designed to achieve fault tolerant control and external disturbance rejection. Corresponding stability of the closed-loop control system is analyzed using Lyapunov stability theory. Apply this method to trajectory tracking control of work-class ROVs, the simulation results validate that great fault tolerant capability and a good performance of external disturbance rejection can be achieved even under partial loss of propeller effectiveness.

The effect of the Aharonov–Bohm potential on the optical polaron solitons is considered by making use of vibration configuration resulting from the energy minimum. Two new polaron solutions with solitary wave form and their relevant properties have been obtained. The results show that the soliton's shape, location, self-trapping energy and effective mass depend on the Aharonov–Bohm dux. At the same time, the bell solitons appear at the polaron energy band, while the kink excitation at the top.

Compared with the general damper, the MR fluid damper has the advantages of adjustable damping, large damping force and intelligence. Magneto rheological fluid damper is a unique role in the study of vibration, shock absorption, and tactile feedback. When the semi-active vibration control of the structure is carried out by the MR damper, the more accurate mechanical model of the damper is one of the key factors to achieve the better control effect of the MR damper. In this paper, the mechanical model of several magneto rheological fluid dampers is analyzed, and the characteristics are analyzed, and the design of MR fluid damper is performed on the basis of the analysis results.

This paper used the airflow organizations of a bulldozer cab as the research object, and the physical model and mathematical model of the three-dimensional airflow is played, and computational fluid dynamic software FLUENT is used to simulate the airflow organizations. The governing equations were solved by using the RNGk- e two equation turbulence model and SIMPLE algorithm. We obtained the simulation results of temperature field and velocity field distribution of different air-supply modes in the driving room of the bulldozer in summer. The results show airflow distribution by different types of air-supply of the air conditioning of the bulldozer cab, which provides a theoretical basis to improve the thermal environment, and it has guiding function to the design of air duct of the engineering vehicle.

The model of diesel engine and its EGR model were established in the AVL BOOST. The model's validity was verified by comparing with the data of engine bench test. The working conditions selected were 25%, 50%, 75% and 100% load under rated speed. Simulation results show that with the augment of the EGR rate, NOX emissions decreased. When the opening degree of the EGR change from 0 to 100%, the NOX of each working conditions decrease 46.23%, 42.2%, 33.97% and 32.3% respectively. At the same time, with the EGR valve opening increase, the reduction of NOX is extremely significant.

This article simply introduces a new material magneto-rheological fluid (MRF) and its widely used, and developed a new type of magneto-rheological dynamometer based on the rheological properties of MRF. This dynamometer introduces magneto-rheological fluid as the working medium, and using the shear yield stress of magneto-rheological fluid in a magnetic field to transmit torque. The paper explored the working mechanism of MR dynamometer, established the torque transmission model of MR dynamometer, and analyzed the flow properties of MRF in the dynamometer under steady-state based on Bingham model and fluid momentum equation.

Since 2007, Honda China Eco Mileage Challenge was held for 7 years, so far, nearly hundred teams participated in the competition. Although the national ranking of our school’s fuel econopower cars is ideal, but the competition results between our school and high level universities is remote. For raising the grade of the econopower car, this paper analyzed the articles about econopower car that published in recent years, discusses the main research direction of econopower car and main achievements, analyse it from the main research direction and research method, offer the technology of econopower car at current in domestic, summarizes the research trend of econopower car, make guidance for the future design of econopower car, also.

The paper was based on multivariable joint optimization. It established an optimization process of diesel engine intake system. The simulation model was built in AVL-BOOST and tested by experiments. As the design variables of intake system parameters (diameter and length of intake duct and intake manifold) were used to orthogonal test. Through the calculation of the engine performance optimization, the sum of paper was the impact of key parameters of the intake system on the performance of engine, and the influence of variable parameters on the volumetric efficiency of engine. These works provided a theoretical reference of intake system optimization design.

Magnetorheological fluid is a widespread attention smart materials in recent years, which consists of soft magnetic particles, carrier liquid and additives. The paper details the characteristics, composition and rheological principle of MRF and the application of magneto-rheological fluid in engineering and the working principle of magneto-rheological fluid devices, provides a basis understanding for the scholars of magneto-rheological technology and components.

As a kind of new intelligent material, magneto-rheological fluid (MRF) has been receiving more and more attentions and applications. In this paper, the components of magneto-rheological fluid and its performance characteristics are mainly introduced. Besides, the authors analyze the advantages of MRF in practical application and its present situation of application in engineering. Finally, the application of MRF in engine dynamometer is studied in detail which will widen the application of magneto-rheological fluid.

Automobile automatic transmission is a complex system integrates machine, electricity, liquid, in terms of its fault diagnosis has the characteristics of uncertainty and high complex correlation, thus put forward the Bayesian network based on the theory of probability and theory of the fault tree for fault diagnosis methods of automobile automatic transmission, it has a certain value for application. Take a failure automatic transmission as an example, analyzes the causes of the automatic transmission fault and the relationship between the affecting factors, according to the properties of the automatic transmission fault establishes a Bayesian network model, and through calculating sensitivity to determine the probability of a certain causes to the automatic transmission fault. The results show that the method is operable in automatic transmission fault diagnosis, diagnosis results are accurate and credible.

The software Q-das used in statistical analysis of the production process can realize the real-time monitoring during the production process. So as to effectively support the needs of the factory in data management, long-term backup and automatic report generation. This paper tells some specific evaluation method of statistical quality control, such as single value chart, control charts, process capability index, etc. Through these configurations of figures, tables, and statistical analysis, “correctly observe” the entire production process. Control and suppress the fluctuations that occur during production. At last, this paper tells the Q-das software in statistical process control analysis application based on a specific example.

Magnetorheological fluids have received widespread attention as smart materials due to their tunable properties. MRF consists of three key components including, soft magnetic particles, carrier liquids, and additives. This review details the characteristics, composition, and rheological principle of MRF, working principle of MRF devices, and their applications in other engineering arenas. The aim is to provide a basis understanding of magneto-rheological components and technology to the readers.

The dynamometer measuring device through the magnetic rheological fluid self-designed, analyzes the basic characteristics of magneto rheological fluid, and then through the experimental study on the temperature characteristics of magneto rheological fluid. Dynamometer with magneto rheological fluid (MRF) was tested, in different conditions, when the system reached the steady state, temperature changes in the key points of the rotary. And through the analysis, the temperature distribution of the device was obtained, which provides the theoretical basis for the effect of temperature on transmission performance. Then, the obtained results, which can provided a good reference for the design of MRF gearing to optimum design and intelligent cooling system.

Based on the research of the new material magnetorheological fluid, magnetorheological fluid dynamometer is designed. Under the premise of certain structure size and material, there is a one-to-one correspondence between MRF dynamometer loading current and load torque provided with the machine electricity and the theoretical calculation. This papergives the design method and specific geometric parameters of magnetorheological fluid dynamometer. The process of magnetorheological fluid dynamometer theory design is obtained by taking a specific model motor as an example, which provides a theoretical basis for the application of MRF in the field of dynamometer