Quantum-interference-induced Magnetization in Mesoscopic Loop Interferometers

Hai Tao Wang,Sam Young Cho,Taeseung Choi 한국물리학회 2013 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.63 No.10

We theoretically investigate quantum interference effects in mesoscopic loop interferometers. In the absence of an Aharonov-Bohm flux, the asymmetry of the arm length of the interferometer can induce a magnetic polarization current circulating along the interferometer loop. We clarify the existing regions of magnetic polarization current in terms of the dimensionless wavevector and a parameter for the asymmetric arm lengths. The magnetic polarization current is found to have a periodic diamond structure that can be characterized by magnetic and non-magnetic diamond zones. The applied magnetic flux develops a concave diamond-shaped non-magnetic region inside the magnetic diamond zones. When the magnetic flux varies across Φ= (2n + 1)π/2, with n being an integer, the magnetic diamond zone becomes a non-magnetic diamond zone and vice versa. In addition, the unique behaviors of the transport current flowing through the interferometer are discussed in association with the magnetic polarization current circulating along the interferometer loop. Finally, the magnetic moments induced at a finite bias are shown to be sufficiently large to be observed experimentally.

Extraskeletal Ewing Sarcomas in Late Adolescence and Adults: A Study of 37 Patients

Tao, Hai-Tao,Hu, Yi,Wang, Jin-Liang,Cheng, Yao,Zhang, Xin,Wang, Huan,Zhang, Su-Jie Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.5

Background: Extraskeletal Ewing sarcoma (EES)/primitive neuroectodermal tumours (PNET) are rare soft tissue sarcomas. Prognostic factors and optimal therapy are still unconfirmed. Materials and Methods: We performed a retrospective analysis on patients to explore the clinic characteristics and prognostic factors of this rare disease. A total of 37 patients older than 15 years referred to our institute from Jan., 2002 to Jan., 2012 were reviewed. The characteristics, treatment and outcome were collected and analyzed. Results: The median age was 28 years (range 15-65); the median size of primary tumours was 8.2 cm (range 2-19). Sixteen patients (43%) had metastatic disease at the initial presentation. Wide surgical margins were achieved in 14 cases (38%). Anthracycline or platinum-based chemotherapy was performed on 29 patients (74%). Radiotherapy was delivered in 13 (35%). At a median follow-up visit of 24 months (range 2-81), the media event-free survival (EFS) and overall survival (OS) were 15.8 and 30.2 months, respectively. The 3-year EFS and OS rates were 24% and 43%, respectively. Metastases at presentation and wide surgical margins were significantly associated with OS and EFS. Tumour size was significantly associated with OS but not EFS. There were no significant differences between anthracycline and platinum based chemotherapy regarding EFS and OS. Conclusions: EES/PNET is a malignant tumour with high recurrence and frequent distant metastasis. Multimodality therapy featuring wide surgical margins, aggressive chemotherapy and adjuvant local radiotherapy is necessary for this rare disease. Platinum-based chemotherapy can be used as an adjuvant therapy.

Feedback Linearization Control of Chaos Synchronization in Coupled Map-Based Neurons Under External Electrical Stimulation

Hai-Tao Yu,Yiu Kwong Wong,Wai Lok Chan,Kai Ming Tsang,Jiang Wang 제어·로봇·시스템학회 2011 International Journal of Control, Automation, and Vol.9 No.5

In this paper, the dynamics of single and two electrically coupled map-based neurons under external electrical stimulation is studied. In order to realize the synchronization of two chaotic spiking neurons, a controller based on the idea of feedback linearization is proposed. The simulation results demonstrate the effectiveness of this developed control method. An important feature of the feedback control is that the amplitude of control signal tends to zero as soon as the synchronization is achieved.

Robust Finite-time Attitude Tracking Control of Rigid Spacecraft Under Actuator Saturation

Hai-Tao Chen,Shen-Min Song,Zhi-Bin Zhu 제어·로봇·시스템학회 2018 International Journal of Control, Automation, and Vol.16 No.1

This paper investigates the robust finite-time attitude tracking control problem for rigid spacecraft considering the modeling uncertainty, external disturbance and actuator saturation. An auxiliary system is proposed to directly compensate for the saturated control input. First, the basic controller is formulated based on the fast nonsingular terminal sliding mode surface (FNTSMS), the fast-TSM-type reaching law and the auxiliary system in the presence of upper bounded external disturbance. Then, when facing system uncertainty which consists of both modeling uncertainty and external disturbance and has upper bounded first derivative, the extended state observer (ESO) is associated with the first controller to improve the robustness of control system. Furthermore, to handle more general system uncertainty which is upper bounded by a polynomial function of the closed-loop system states, a continuous adaptive controller is designed to compensate for the total system uncertainty on line. The proposed controllers are able to deal with system uncertainty, input singularity and actuator saturation, while simultaneously providing fast finite-time convergence speed for the control system. And the problems of complex parameters selection process and repeated differentiations of nonlinear functions can be avoided. Rigorous stability analyses are given via the Lyapunov stability theory and digital simulations are conducted to illustrate the effectiveness of the proposed controllers.

Reactive Synthesis of ZrB2-based Ultra High Temperature Ceramics

Hai-Tao Liu,Guo-Jun Zhang† 한국세라믹학회 2012 한국세라믹학회지 Vol.49 No.4

Reactive processing, such as reactive hot pressing (RHP) and reactive spark plasma sintering (R-SPS), is effective densification method to prepare ZrB2-based ultra high temperature ceramics (UHTCs). The present paper reviewed some typical reactive processing of ZrB2-based UHTCs. All the reactions from the starting materials in the reactive processing are thermodynamically favorable, which generate enough energy and driving force for the densification of the final products under a relatively low temperature. Besides, compared with non-reactive processing, anisotropic ZrB2 grains, such as ZrB2 platelets, can only be obtained in the reactive processing, resulting in an improvement of the mechanical properties.

Ramp-Strike Risk Evaluation Making of Carrier-Based Aircraft

Hai-tao Jiang,Xiao-dong Su,Hui Li 보안공학연구지원센터 2014 International Journal of Control and Automation Vol.7 No.10

To make “Ramp-Strike Risk” evaluation making accurately, this paper introduces a new wave-off risk assessment method based on neural network of carrier-based aircraft. On account of defining “Wave-Off Retain Clearance”, the wave-off operation system with military power and vertical elevator is established as evaluation medium. The “Wave-Off Risk State Area” established by limited wave-off envelope can reduce network training burden, and the quantitative “Ramp-Strike Risk” function with flight state is presented through BP neural network finally. Simulation results show that the risk with flight states can be predicted by using new estimation method, moreover auxiliary rectification and early-warning for landing is provided.

Dependency Distance as a Metric of Language Comprehension Difficulty

Hai Tao Liu 서울대학교 인지과학연구소 2008 Journal of Cognitive Science Vol.9 No.2

Linguistic complexity is a measure of the cognitive difficulty of human language processing. The present paper proposes dependency distance, in the framework of dependency grammar, as an insightful metric of complexity. Three hypotheses are formulated: (1) The human language parser prefers linear orders that minimize the average dependency distance of the recognized sentence (2) There is a threshold that the average dependency distance of most sentences or texts of human languages does not exceed (3) Grammar and cognition combine to keep dependency distance within the threshold. Twenty corpora from different languages with dependency syntactic annotation are used to test these hypotheses. The paper reports the average dependency distance in these corpora and analyzes the factors which influence dependency distance. The findings-that average dependency distance has a tendency to be minimized in human language and that there is a threshold of less than 3 words in average dependency distance and grammar plays an important role in constraining distance-support all three hypotheses, although some questions are still open for further research.

Stress intensity factors for double-edged cracked steel beams strengthened with CFRP plates

Hai-Tao Wang,Gang Wu,Yu-Yang Pang,Habeeb M. Zakari 국제구조공학회 2019 Steel and Composite Structures, An International J Vol.33 No.5

This paper presents a theoretical and finite element (FE) study on the stress intensity factors of double-edged cracked steel beams strengthened with carbon fiber reinforced polymer (CFRP) plates. By simplifying the tension flange of the steel beam using a steel plate in tension, the solutions obtained for the stress intensity factors of the double-edged cracked steel plate strengthened with CFRP plates were used to evaluate those of the steel beam specimens. The correction factor <i>α</i>₁ was modified based on the transformed section method, and an additional correction factor <i>φ</i> was introduced into the expressions. Threedimensional FE modeling was conducted to calculate the stress intensity factors. Numerous combinations of the specimen geometry, crack length, CFRP thickness and Young's modulus, adhesive thickness and shear modulus were analyzed. The numerical results were used to investigate the variations in the stress intensity factor and the additional correction factor <i>φ</i>. The proposed expressions are a function of applied stress, crack length, the ratio between the crack length and half the width of the tension flange, the stiffness ratio between the CFRP plate and tension flange, adhesive shear modulus and thickness. Finally, the proposed expressions were verified by comparing the theoretical and numerical results.

Bond-Alternation-Induced Topological Quantum Gaussian Transition and Topological Quantum Crossover in Ising Chains with the Dzyaloshinskii-Moriya Interaction

Wang Hai Tao,Cho Sam Young 한국물리학회 2020 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.77 No.12

Non-local orders, entanglement entropy, and quantum fidelity are investigated in an infinite-size bond-alternating Ising chain with the Dzyaloshinskii-Moriya interaction by employing the infinite matrix product state representation with the infinite time evolving block decimation method. Directly computing two distinct types of finite string correlations for very large lattice distances, in contrast to an extrapolated extreme value for finite size chains, reveals two topologically ordered phases. As the bond alternation varies, a topological quantum phase transition with continuously variable critical exponents along the phase boundary occurs between the two Haldane phases for a Dzyaloshinskii-Moriya interaction stronger than the Ising interaction while a topological quantum crossover between them happens through an intermediate antiferromagentic phase demonstrated with the quantum fidelity for a Dzyaloshinskii-Moriya interaction weaker than the Ising interaction. The critical exponents of the order parameters and the central charges from the entanglement entropy quantify the universality classes of the phase transition points. Anisotropic Heisenberg types of spin chains with bond alternations are finally discussed to share the same criticality.

In vitro and in vivo Evaluation of the Antitumor Efficiency of Resveratrol Against Lung Cancer

Yin, Hai-Tao,Tian, Qing-Zhong,Guan, Luan,Zhou, Yun,Huang, Xin-En,Zhang, Hui Asian Pacific Journal of Cancer Prevention 2013 Asian Pacific journal of cancer prevention Vol.14 No.3

Lung cancer remains a deadly disease with unsatisfactory overall survival. Resveratrol (Res) has the potential to inhibit growth of several types of cancer such as prostate and colorectal examples. In the current study, we evaluated in vitro and in vivo anticancer efficiency of Res in a xenograft model with A549 cells. Cell inhibition effects of Res were measured by MTT assay. Apoptotis of A549 cells was assessed with reference to caspase-3 activity and growth curves of tumor volume and bodyweight of the mice were measured every two days. In vitro cytotoxicity evaluation indicated Res to exert dose-dependent cell inhibition effects against A549 cells with activation of caspase-3. In vivo evaluation showed Res to effectively inhibit the growth of lung cancer in a dose-dependent manner in nude mice. Therefore, we believe that Res might be a promising phytomedicine for cancer therapy and further efforts are needed to explore this potential therapeutic strategy.