An improved YOLOv7 for the state identification of sliding chairs in railway turnout

The sliding chairs are important components that support the switch rail conversion in the railway turnout.Due to the harsh environmental erosion and the attack from the wheel vibration,the failure rate of the sliding chairs accounts for up to 10%of the total failure number in turnout.However,there is little research carried out in the existing literature to diagnose the deterioration states of the sliding chairs.To fill out this gap,by utilizing the images containing the sliding chairs,we propose an improved You Only Look Once version 7(YOLOv7)to identify the state of the sliding chairs.Specifically,to meet the challenge brought by the small inter-class differences among the sliding chair states,we first integrate the Convolutional Block Attention Module(CBAM)into the YOLOv7 backbone to screen the information conducive to state identification.Then,an extra detector for a small object is customized into the YOLOv7 network in order to detect the small-scale sliding chairs in images.Meanwhile,we revise the localization loss in the objective function as the Efficient Intersection over Union(EIoU)to optimize the design of the aspect ratio,which helps the localization of the sliding chairs.Next,to address the issue caused by the varying scales of the sliding chairs,we employ K-means++to optimize the priori selection of the initial anchor boxes.Finally,based on the images collected from real-world turnouts,the proposed method is verified and the results show that our method outperforms the basic YOLOv7 in the state identification of the sliding chairs with 4%improvements in terms of both mean Average Precision@0.5(mAP@0.5)and F1-score.

Aging effect and test-retest reliability of the sinusoidal harmonic acceleration test and velocity step test using nanotorque rotatory chair

Introduction:Rotatory chair testing has been used to evaluate horizontal canal function.Frequently used tests include sinusoidal harmonic acceleration test(SHAT)and velocity step test(VST).Objectives:Assessment of age effect on the SHAT and VST and assessment of test-retest reliability of the parameters of those two tests.Methods:A prospective study was performed on 100 subjects with no ear or vestibular complaints and normal vestibular evaluation.They were divided into two groups;Group A:below 50 years of age and Group B:50 years of age or above.SHAT was presented at frequencies 0.02,0.04,0.08,0.16,0.32,0.64 Hz with a peak velocity of 60°/s.VST was performed using a maximum velocity of 100°/s with acceleration and deceleration of 200°/s2.Thirty subjects were tested twice to assess reliability.Results:Study participants ranged in age from 20 to 67 years.Regarding group A,the mean age was30.92±7.31 and 55.36±4.61 for group B.No significant differences were found in SHAT parameters between the two groups.As well,there was no significant difference in VST per-rotatory time constant,however,post-rotatory time constant was significantly longer for Group B(P value<0.05).Intraclass correlation coefficient(ICC)values showed moderate to good reliability(ICC 0.5800.818)for SHAT parameters for the lower frequencies and indicated moderate reliability for VST time constant(ICC 0.5090.652).Conclusions:Age has no significant effect on the parameters of SHAT and VST.Test-retest reliability is generally good for both tests.

Sn-doped BiOCl nanosheet with synergistic H^(+)/Zn^(2+)co-insertion for“rocking chair”zinc-ion battery

The development of insertion-type anodes is the key to designing“rocking chair”zinc-ion batteries.However,there is rare report on high mass loading anode with high performances.Here,{001}-oriented Bi OCl nanosheets with Sn doping are proposed as a promising insertion-type anode.The designs of cross-linked CNTs conductive network,{001}-oriented nanosheet,and Sn doping significantly enhance ion/electron transport,proved via experimental tests and theoretical calculations(density of states and diffusion barrier).The H^(+)/Zn^(2+)synergistic co-insertion mechanism is proved via ex situ XRD,Raman,XPS,and SEM tests.Accordingly,this optimized electrode delivers a high reversible capacity of 194 m A h g^(-1)at 0.1 A g^(-1)with a voltage of≈0.37 V and an impressive cyclability with 128 m A h g^(-1)over 2500 cycles at 1 A g^(-1).It also shows satisfactory performances at an ultrahigh mass loading of 10 mg cm^(-2).Moreover,the Sn-Bi OCl//MnO_(2)full cell displays a reversible capacity of 85 m A h g^(-1)at 0.2 A g^(-1)during cyclic test.

Cementing Ties Uganda’s chairing of G77+China to heighten relationship with China

For the past six decades,Uganda and China have enjoyed remarkable bilateral relations and Uganda being recently elected to chair G77+China mechanism is set to drive the relationship to even greater heights.That’s according to Uganda’s First Deputy Prime Minister Rebecca Kadaga,who made the remarks recently while speaking at an event to mark the 74th anniversary of the founding of the People’s Republic of China.In response,the charge d’affaires at the Chinese Embassy in Uganda,Fan Xuecheng,toasted the long-standing friendship between the peoples of China and Uganda.

Chair Tilings非周期艺术图案的生成

在Chairtilings结构的基础上构造出新的函数来生成彩色非周期图案,其原胞具有丰富的图形结构,为计算机实现非周期拼砌提供了新方法·

不同手术方案对Chair畸形Ⅰ型患者术后临床疗效的观察

目的探讨不同手术方案对Chair畸形Ⅰ型患者术后的临床疗效,为Chair畸形Ⅰ型患者的治疗提供更优越的手术方案。方法选取2015年5月至2018年4月就诊的128例诊断为Chair畸形Ⅰ型的患者,依据随机数字表法患者随机分为2组,每组64例。2组患者给予术前相关检查,其中对照组给予改良后颅窝减压术治疗,研究组给予后颅窝减压术联合硬膜成形术及小脑扁桃体切除术治疗,2组患者随访12个月,评价2组患者的住院时间、短期临床症状改善情况、并发症发生率、脊髓空洞缓解率及肢体感觉障碍缓解率。结果治疗后2组患者的短期临床症状、脊髓空洞缓解率及肢体感觉障碍缓解率均较前明显改善(P<0.05);研究组患者的住院时间、短期临床症状改善情况和并发症发生率均明显优于对照组(P<0.05),2组患者术后1年的肢体感觉障碍缓解率及脊髓空洞缓解率与对照组比较差异无统计学意义(P>0.05)。结论后颅窝减压术联合硬膜成形术及小脑扁桃体切除术与改良后颅窝减压术比较,临床疗效较为显著,可有效改善患者的相关临床症状,减少并发症的发生率,并且有效缩短患者的住院时间,减少患者及其家庭的经济负担,但是两种术式对于患者的肢体感觉障碍的缓解率及脊髓空洞缓解率未见明显异常,说明对于临床症状及体征不同的患者应采取不同的治疗方案,因人而异与个体化的手段相结合。

单纯后颅窝减压术与后颅窝减压硬膜扩大成形术治疗chair畸形的疗效比较

目的分析单纯后颅窝减压术与后颅窝减压硬膜扩大成形术治疗chair畸形的疗效。方法将60例chair畸形患者按照术式的不同分为观察组和对照组各30例,分别采取后颅窝减压硬膜扩大成形术、单纯后颅窝减压术治疗,对比两组患者术后效果。结果观察组总有效率96.7%较对照组总有效率60%高,其症状消失率明显高于对照组,p<0.05;术后未发生脑脊液漏、颅内感染等并发症,恢复良好。结论颅窝减压硬膜扩大成形术治疗chair畸形疗效优于单纯后颅窝减压术,效果更为显著。

清代宫廷交椅鉴赏

交椅由胡床演变而来,是古人精湛工艺及文化思想的集合体,因其便携性,促使我国古代起居方式变得更为灵活多样,特别是在行军、出游等活动中。自宋代以来,交椅在营事活动中逐渐发展成为身份地位的象征,其装饰外观受礼制约束。本文通过梳理不同朝代相关交椅的古籍、绘画等资料,以故宫博物院馆藏3把清代交椅实物为例,进行鉴赏及历史文化挖掘,解读交椅在装饰中的制度性、实用性与艺术性,以期让交椅的设计者与使用者更好地了解其所承载的文化内涵。

A Flexible and Adaptive Multi-bimensional Back System Based on Ergonomics

According to the study on seat-back curves about different people, the method that using two arc-shaped roofs to give back supporting force of the human body is proposed. Through a clever design application of piezoelectric sensor, microcontroller, motors, and arc-shaped roofs form a closed loop control system. Through the design of horizontal and vertical adjustment mechanism, a flexible and adaptive multi-dimensional back can reduce the harm to human spine which caused by poor posture and sedentary life style. Model building and stress analysis are done by Inventor software to verify the mechanism of strength.

Wireless Head Gesture Controlled Robotic Wheel Chair for Physically Disable Persons

A robotic wheelchair is assumed to be capable of doing tasks like navigation, obstacle detection, etc. using sensors and intelligence. The initial part of the work was development of a cap controlled wheelchair to test and verify the gesture operation. Following that, a real time operating wheelchair was developed consisting of mode changing option between joystick control mode and head gesture control mode as per as the user’s requirement. The wheelchair consists of MPU6050 sensor, joystick module, RF module, battery, dc motor, toggle switch and Arduino. The movement of the head is detected by MPU6050 and the signal is transmitted to the microcontroller. Then the signal is processed by controller and motion of wheelchair is enabled for navigation. The wheelchair was capable of moving left, right, forward and backward direction. The speed of the wheelchair was 4.8 km/h when tested. Design objective of the wheelchair included cost effectiveness without compromising safety, flexibility and mobility for the users.

The Cardiac Function in the Beach Chair Position under General Anesthesia

Background: Shoulder surgery is performed in the beach chair position (BCP). The systemic arterial blood pressure (BP) must be increased to prevent cerebral hypoperfusion. However, it is not clear how the cardiac function is affected when BP increase to maintain cerebral perfusion pressure in anesthetized patients. Methods: An analysis was performed using the data from 13 patients. We prepared a parallel circuit using a FloTrac Sensor transducer and an arterial BP transducer. Following the transfer of the patient to the BCP under general anesthesia, the FloTrac Sensor transducer was placed at the level of the fourth intercostal space, the arterial BP transducer was placed at the external auditory meatus level. We selected two points before surgery (120 s apart), during which the mean arterial BP (mABP) at the level of the brain was stable and at which the values in the supine position and the BCP were within 5 mmHg. Results: While the patients were in the supine position, the mean mABP at the mid-axillary level was 65.7 mmHg. In the BCP, the mean mABP was 66.5 mmHg at the external auditory meatus and 80.7 mmHg at the fourth intercostal space. The cardiac index changed from 2.2 (supine position) to 2.5 l/min/m2 (BCP). The stroke volume index was significantly increased from 35.8 to 42.3 ml/m2 (P = 0.003). The heart rate changed from 63.0 to 58.6 beats/min. The stroke volume variation was significantly decreased from 12.4% to 8.8% (P = 0.024). Conclusion: In order to ensure patient safety, close attention should be paid to the systemic cardiovascular changes that occur when the BP is increased.

Design and Structural Analysis of Flexible Wearable Chair Using Finite Element Method

The flexible wearable chair is like a light weight mobile exoskeleton that allows people to sit any-where in any working position. The traditional chair is difficult to move to different working locations due to its large size, heavy weight (~5 - 7 kg) and rigid structure and thus, they are inappropriate for workplaces where enough space is not available. Flexible wearable chair has a gross weight of 3 kg as it utilizes light-weight aluminium alloy members. Unlike the traditional chair, it consists of kinematic pairs which enable taking halts between continuous movements at any working position and thus, it is capable of reducing the risk of the physical musculoskeletal disorder substantially among workers. The objective of this paper is to focus on the mechanical design and finite element analysis (FEA) of the mechanism using ANSYS® software. In the present work, all the parts of the mechanism are designed under static load condition. The results of the analysis indicate that flexible wearable chair satisfies equilibrium and stability criterion and is capable of reducing fatigue during working in an assembly line/factory.

Chair Professors and Visiting Professors of ＂Chang Jiang Scholars Program＂

In responding to the ongoing development needs of the university, we are seeking to recruit Chair Professors and Visiting Professors of ＂Chang Jiang Scholars Program＂ at home and abroad.

Chair Professors and Visiting Professors of "Chang Jiang Scholars Program"

In responding to the ongoing development needs of the university, we are seeking to recruit Chair Professors and Visiting Professors of ＂Chang Jiang Scholars Program＂ at home and abroad. School of Medicine, Tsinghua University

Randomized Trial of the Use of Dexmedetomidine vs. Propofol after Regional Blockade in Shoulder Surgery Patients in Beach Chair Position

Background: Propofol is often the drug of choice for ambulatory orthopedic cases. However, propofol can be associated with apnea or other events requiring airway interventions. Dexmedetomidine (Dex) has the unique pharmacologic profile of providing sedation without respiratory depression. This is particularly relevant in patients with morbid obesity and/or challenging airways. The hypotheses were: 1) Propofol would cause more apnea or require more airway manipulations than dexmedetomidine;2) Propofol would have shorter post anesthesia unit recovery times;and 3) Dexmedetomidine would be associated with more bradycardia and hypotension. Methods: After IRB approval, 50 patients were randomized to receive either propofol or Dex for Total Intravenous anesthesia (TIVA) after interscalene brachial plexus block was performed preoperatively under ultrasound guidance. The main end points that we measured where: airway interventions, intra-operative bradycardia, hypotension, and PACU length of stay. Results: There were more airway interventions in the propofol group compared to the Dex group. Additionally, the Dex group had significantly longer PACU stays. Conclusion: We would recommend that Dex should be preferentially considered for patients predisposed to airway obstruction;however, the standard use of Dex over Propofol needed to reconsider since the use of Dex as the agent for TIVA was associated with longer PACU stays.

Paraplegia by Acute Cervical Disc Herniation after Shoulder Arthroscopic Surgery in Beach-Chair Position

Paraplegia after non-cervical spine surgery under general anesthesia is a rare devastating postoperative complication [1]. A patient with shoulder pain was scheduled for shoulder arthroscopy due to rotator cuff repair. Arthroscopic shoulder surgery was performed with the patient in the beach-chair. Postoperatively, patients complained the weakness of both lower leg and marked numbness and tingling in the both arms. MRI showed a herniated intervertebral disc between C6 and C7 with spinal cord compression. Despite urgent discectomy, the patient remained dysesthesia of both upper extremities for 6 months. The purpose of this report is to introduce our case with a paraplegia observed after arthroscopic shoulder surgery in beach-chair position because of acute cervical herniation.

The Case of the Broken Chair

Some time ago I discovered that one of the chairs in myfront hall had a broken leg.I didn’t foresee any great difficultyin getting it mended,as there are a whole lot of antique shopsin the Pimlico Road which is three minutes’walk from myflat,so I set forth one morning carrying the chair with me.Iwent into the first shop confidently expecting a friendly recep-

Workshop for ISO chairs and convenors held in Hangzhou

A s a means to carr y out educational ac tivities and cultivate talents on international standardization,the workshop for ISO Chairs and Convenors co-organized by ISO and SAC was held from October 30 to November 8at China Jiliang University in Hangzhou,eastern China’s Zhejiang province.Five ISO experts were invited to give lectures on the exper tise on technical work process,

Comparison of the Effectiveness of TRV Chair and Canalith Repositioning Procedure (CRP) for the Treatment of Benign Paroxysmal Positional Vertigo (BPPV)

The primary goal of this research is to evaluate the efficacy of traditional manual canalith repositioning procedures (CRP) to that of automated multi-axial repositioning chair (TRV). A total of 37 BPPV positive patients were distributed into two groups. The first group consisted of 20 patients, 10 under 50 years old (young group) and 10 over 50 years old (old group), who received TRV chair treatment, whereas the remaining 17 patients, 7 under 50 years old (young group) and 10 over 50 years old (old group) received CRP treatment. The DHI and VAS questionnaires were given to the patients before and after treatment, and the results were compared. The average VAS score for TRV patients was 84.5% (young group) and 77.5% (old group). These patients’ DHI results were as follows: for young patients, 10% had a mild handicap, 80% had a moderate handicap, and 10% had a severe handicap, while for the elderly, 40% had a mild handicap, 40% had a moderate handicap, and 20% had a severe handicap. The results improved significantly after the first treatment session. Old patients had a VAS of 28%, 30% had a mild handicap and only 10% had a moderate handicap. However, only 43% of the young group and 30% of the old group who underwent standard CRP suffered from mild handicap and had a VAS of 20% and 34.3% successively. The third session revealed that all patients in the TRV chair group had no handicap, whereas the CRP patients indicated that they still had a mild handicap. Upon analyzing the results, both treatment methods revealed the same efficacy in treating single canal BPPV. However, TRV chair appeared to be superior to traditional CRP in treating multi-canal BPPV.