Numerical investigation of sound transmission loss of circular plates embedded with acoustic black hole

The acoustic black hole (ABH) can be utilized to achieve aggregation of flexural wave in structures with the feature that the thickness gradually reduced to zero with a power exponent no less than 2. These characteristics could be applied in vibration reduction, noise attenuation or improving sound insulation. To investigate the sound transmission loss of circular plates embedded with acoustic black hole, series of vibro-acoustic coupling finite element models (FEM) for TL analysis of ABH circular plates were established by automatic matched layer (AML) method in this paper and the simulation results show that the circular plate with a single ABH embedded in the center position can significantly improve the sound transmission loss in stiffness-controlled region, and at the first-order resonance frequency

Impact of English-language Proficiency on Chinese Expatriates’ Adjustment to Overseas Assignments

With the emergence of Chinese multinationals, increasingly large number of Chinese expatriates work overseas. However, little research has been conducted to investigate Chinese expatriates’ adjustment to overseas assignments. Drawing on prior studies in the areas of linguistics, communication, and business, the current study examines the impact of the English-language proficiency on the Chinese expatriates’ adjustment to overseas assignments. A Chinese multinational in the information technology industry, Company ABC, was selected as a subject company. Quantitative research method was adopted. The quantitative data were collected through a survey of 190 Chinese expatriates from Company ABC. Pearson’s Correlation Coefficient was performed to examine the relationships between English-language proficiency and variables related to the Chinese Expatriates’ Adjustment to Overseas Assignments. The findings show that English-language proficiency was found to enhance Chinese expatriates’ adjustment moderately. Moreover, further analysis indicates that different type of English-language proficiency affects different aspect of Chinese expatriates’ adjustment

Automated pick-up of suturing needles for robotic surgical assistance

Robot-assisted laparoscopic prostatectomy (RALP) is a treatment for prostate cancer that involves complete or nerve sparing removal prostate tissue that contains cancer. After removal the bladder neck is successively sutured directly with the urethra. The procedure is called urethrovesical anastomosis and is one of the most dexterity demanding tasks during RALP. Two suturing instruments and a pair of needles are used in combination to perform a running stitch during urethrovesical anastomosis. While robotic instruments provide enhanced dexterity to perform the anastomosis, it is still highly challenging and difficult to learn. In this paper, we presents a vision-guided needle grasping method for automatically grasping the needle that has been inserted into the patient prior to anastomosis. We aim to automatically grasp the suturing needle in a position that avoids hand-offs and immediately enables the start of suturing. The full grasping process can be broken down into: a needle detection algorithm; an approach phase where the surgical tool moves closer to the needle based on visual feedback; and a grasping phase through path planning based on observed surgical practice. Our experimental results show examples of successful autonomous grasping that has the potential to simplify and decrease the operational time in RALP by assisting a small component of urethrovesical anastomosis

The impact of organizational stigmatization on the operational risk and performance of overseas subsidiaries: empirical evidence from Chinese multinational enterprises

This study used the global database of events, language, and tone of international public opinion big data to measure organizational stigmatization against China. It then used an econometric model to investigate the impact of organizational stigmatization on the operational risk and performance of overseas subsidiaries of Chinese multinational enterprises. The results show that: (1) organizational stigmatization increases overseas subsidiaries’ operational risk and reduces their operational performance, which is more evident in overseas subsidiaries of state-owned enterprises; (2) the host country’s political stability weakens the organizational stigmatization’s positive impact on overseas subsidiaries’ operational risk. The geographical distance between the home and host countries strengthens organizational stigmatization’s positive impact on overseas subsidiaries’ operational risk; (3) the host country’s political stability and the geographical distance between the home and host countries have no moderating effect on organizational stigmatization and overseas subsidiaries’ operational performance; and (4) organizational stigmatization by the host country reduces overseas subsidiaries’ operational performance via the channel of operational risk. This study innovates the measurement method of organizational stigmatization and lays the foundation for investigating the microeconomic impact of organizational stigmatization from the perspective of overseas subsidiaries

Effect of acoustic black hole parameters on vibration suppression of rectangular plate

The acoustic black hole has the ability to gather and manipulate the flexural wave in the structure, and can be used to achieve vibration suppression of the structure. A group of FEM models for the vibration analysis of the rectangular plate embedded with acoustic black holes were established in this paper. Four monitoring points on the ABH plate were selected to calculate their vibration velocity response in 100 Hz-3 kHz frequency interval. In order to study the effects of acoustic black hole geometric parameters and damping layer geometric parameters on the vibration response of the ABH plate, 15 combinations of different parameters of the maximum ABH diameter, the truncated thickness of the ABH, the power index of the ABH, and the damping layer thickness, the maximum diameter of the damping layer were selected to calculate the vibration velocity response of the four monitoring points. The calculation result can help us understand the effects of acoustic black hole geometric parameters and damping layer geometric parameters on the vibration suppression of rectangular plate