Localization of a spin-orbit coupled Bose-Einstein condensate in a bichromatic optical lattice

We study the localization of a noninteracting and weakly interacting Bose-Einstein condensate with spin-orbit coupling loaded in a quasiperiodic bichromatic optical lattice potential using the numerical solution and variational approximation of a binary mean-field Gross-Pitaevskii equation with two pseudo-spin components. We confirm the existence of the stationary localized states in the presence of the spin-orbit and Rabi couplings for an equal distribution of atoms in the two components. We find that the interaction between the spin-orbit and Rabi couplings favors the localization or delocalization of the BEC depending on the the phase difference between the components. We also studied the oscillation dynamics of the localized states for an initial population imbalance between the two components

A Study on Competitive Strategies of Container Shipping Companies in China

Container transport is a modern mode of transportation. After a long period of development, it has been a mature stage of development nowadays. At this stage, the container transportation technology has developed maturely, and the idea of ​​transporting goods by means of containers has been widely recognized. On the one hand, identified and popularized containers become an important carrier for multimodal transport. It can be said that people’s living is now inextricably linked to containers. On the other hand, the continued steady development of world economy depends on containers transport, and the role of containers is increasingly becoming more and more important. Simultaneously, we are also soberly aware that the container shipping market is a highly free competitive market, with the development of container transportation capacity and the slowdown of the global economy, the container shipping industry nowadays has become an extremely competitive period. The specific performance is as follows: Market concentration is getting higher and higher; Mergers and Acquisitions are developing into a frequent and common form; The scale of companies is getting bigger and bigger; The trend of ships is larger and larger; However the freight rate is absolutely low, so what the container transport companies is under a high pressure. Therefore the container transport enterprises should face up to many opportunities and challenges. Container transport is really progressed and entered into a new period of development. How container companies can develop and grow based on the current market is an urgent issue of Chinese container transport enterprises. The first part of this thesis introduces the research background, significance, research methods and theoretical review of the study; the second part briefly introduces the development status of the container shipping industry from both international and domestic perspectives. Through objective comparison, it is not difficult to analyze the competitive advantages and disadvantages of Chinese container shipping companies; meanwhile, it obviously formulates the development of Chinese container shipping company’s competitive strategy, eventually the enhancement of Chinese container shipping company's competitive strategy, implementation of competitive strategy can promote the development of Chinese container shipping company. Through concrete and specific research, Chinese container shipping companies should adopt and focus on the business strategies in order to achieve new competence due to the great the external environment. Under the guidance of the correct corporate strategy, it can be visual that Chinese container shipping companies can achieve the more significant accomplishments in a fiercely competitive marketing environment.Abstract i 제1장 서론 1 제1절 연구배경과 목적 1 제2절 연구방법과 구성 4 제2장 경쟁전략에 관한 이론적 고찰 5 제1절 전략개념의 발전과정 5 1. 생산관리시대( 1900~1919년) 5 2. 인사 및 조직관리시대( 1919 ~ 1945년 ) 6 3. 마케팅관리시대(1945~1958년) 6 4. 기획관리시대(1959~1972년) 6 5. 전략경영시대( 1973~1980년 중반 ):산업조직론 관점 7 6. 전략경영시대( 1980년대 중반 이후 ):자원준거관점 7 제2절 경쟁우위의 개념 8 1. 자원관리이론 9 2. 경쟁 우위이론 10 3. 동력능력 이론 10 제3절 경쟁전략에 관한 연구방법 11 1. PEST분석방법 11 2. SWOT분석 12 3. "5 Forces" 분석 모델 12 제3장 세계 컨테이너 해운산업의 현황분석 14 제1절 세계 컨테이너 해운시장의 현황 14 제2절 주요 컨테이너 해운시장의 전체적 상황 20 1. 주요 컨테이너 해운기업의 경영상황 20 2. 2017년 글로벌 컨테이너 정기선 시장의 해운 물동량 22 3. 2017년 글로벌 컨테이너 운송 시장의 적재량 24 4. 2017년 글로벌 컨테이너 정기선 운송 시장의 운임 26 제3절 외국계 주요 컨테이너 선사의 현황과 전략 28 1. Maersk 26 2. MSC 34 3. CMA CGM 36 제4절 중국 컨테이너 선사의 현황과 전략 41 1. COSCO 41 2. SINOLINES 45 제5절 글로벌 컨테이너 선사의 비교분석 47 제4장 중국 컨테이너 해운기업의 경쟁전략 수립과 실행 53 제1절 주요 경쟁전략의 실행모델과 원칙 53 제2절 중국 컨테이너 해운기업의 경쟁전략 56 제3절 중국 컨테이너 해운기업의 경쟁전략 실행방안 65 제4절 중국 컨테이너 해운기업의 경쟁전략 실행보장 68 제5장 결론 72 제1절 연구결과의 요약 및 시사점 72 제2절 연구의 한계점과 향후 연구과제 73 참고 문헌 75Maste

What is the impact of tax avoidance on the value and reputation of multinational companies?

The issue of tax avoidance has long been a widespread phenomenon on a global scale. Tax avoidance is also generally recognised in numerous studies as an important corporate decision. This paper first examines the impact of tax avoidance by MNCs on the value of the firm. MNCs, as independent business entities, arrange tax avoidance activities in order to maximise the value of the company. The traditional view that tax avoidance reduces the tax burden and thus increases the value of equity also provides a theoretical basis for companies to implement tax avoidance. However, although tax avoidance gains tax savings for the company, it also increases the potential and unavoidable non-tax costs, which ultimately affect the value of the company. Secondly, this paper examines the relationship between tax avoidance and corporate reputation in MNCs. Corporate reputation is often considered to be an important constraint on tax avoidance by MNCs. Many scholars have also argued that the degree of corporate tax avoidance is negatively related to corporate reputation, but this hypothesis has not been tested using financial data. This paper finds no significant association between tax avoidance and corporate reputation based on empirical research. This suggests that tax avoidance activities do not cause damage to a company's reputation. This paper concludes that tax avoidance by MNCs is negatively correlated with firm value and is not correlated with firm reputation. The results of the study also provide implications for MNCs and tax authorities. Keywords: multinational corporations, tax avoidance, firm value, firm reputatio

FedVCP: A Federated-Learning-Based Cooperative Positioning Scheme for Social Internet of Vehicles

Intelligent vehicle applications, such as autonomous driving and collision avoidance, put forward a higher demand for precise positioning of vehicles. The current widely used global navigation satellite systems (GNSS) cannot meet the precision requirements of the submeter level. Due to the development of sensing techniques and vehicle-to-infrastructure (V2I) communications, some vehicles can interact with surrounding landmarks to achieve precise positioning. Existing work aims to realize the positioning correction of common vehicles by sharing the positioning data of sensor-rich vehicles. However, the privacy of trajectory data makes it difficult to collect and train data centrally. Moreover, uploading vehicle location data wastes network resources. To fill these gaps, this article proposes a vehicle cooperative positioning (CP) system based on federated learning (FedVCP), which makes full use of the potential of social Internet of Things (IoT) and collaborative edge computing (CEC) to provide high-precision positioning correction while ensuring user privacy. To the best of our knowledge, this article is the first attempt to solve the privacy of CP from a perspective of federated learning. In addition, we take the advantages of local cooperation through vehicle-to-vehicle (V2V) communications in data augmentation. For individual differences in vehicle positioning, we utilize transfer learning to eliminate the impact of such differences. Extensive experiments on real data demonstrate that our proposed model is superior to the baseline method in terms of effectiveness and convergence speed

Influence Mechanism of Geometric Characteristics of Water Conveyance System on Extreme Water Hammer during Load Rejection in Pumped Storage Plants

Pumped storage plants (PSPs) have achieved rapid development and deployment worldwide since the penetration of intermittent renewable energy sources (RES). Hydraulic transient analysis in the PSP, to obtain the control parameters such as extreme water hammer pressure, is vital to the safe design of water conveyance system. Empirically, simultaneous load rejection (SLR) is commonly accepted as the control condition for extreme water hammer, while it is not completely true for the PSP. Employing theoretical analysis and numerical simulation, this study systematically investigates the effects of geometric characteristics on the extreme water hammer, and reveals the mechanism leading to the maximum spiral case pressure (SCP) during a two-stage load rejection (TLR) process. The results indicate that the extreme water hammer pressure is closely related to geometric characteristics of the water conveyance system, performing the allocation of the water inertia time constant of the main and branch pipelines. When the water inertia time constant in the branch pipe is dominant (&eta 1 &gt 0.24 for example), the maximum SCP will occur in TLR conditions rather than SLR. Moreover, the maximum SCP is almost the same, providing the water inertia time constants of both the main and branch pipelines are kept constant. Document type: Articl

Assessment of Urban Biodiversity: A Case Study of Beijing City, China

Habitat loss is the most important factor affecting biodiversity. Beijing is an international metropolis with rich biodiversity. With the development of urbanization, biodiversity has been affected to a certain extent in Beijing City. We investigated plant communities in three green land types, parks, residential areas, and roads along an urbanization gradient in the Beijing urban area (inner 6th ring road). Species composition, similarity index, and diversity of plants in urban areas were calculated. The results showed 536 species, belonging to 103 families, and 319 genera in the Beijing urban area. Among them, there were 361 native species and 175 imported species. Eighty species were imported from abroad and 95 species from inland, namely 14.9% and 17.7% of the total species, respectively. The species richness and diversity of trees and shrubs first increased and then decreased along the urbanization gradients, with the decreasing trend from the inner 2nd ring road and the increasing trend from the 3rd–4th ring road. No significant difference was found along the urbanization gradient for herbaceous plants. There were no significant differences in species evenness along the urbanization gradient

Combined effects of penetration and explosion on damage characteristics of a mass concrete target

With the development of the precision guidance technology, the earth-penetrating weapon (EPW) is a huge threat to infrastructures. The objective of this research is to investigate the damage characteristics of mass concrete targets under the combined action of penetration and explosion. The validity of the penetration model is discussed by reproducing a previous experimental test reported in the literature. Meanwhile, a field test about the internal explosion in a concrete cube is conducted to verify the validity of the internal explosion model. Subsequently, damage characteristics of a mass concrete target from the upper part of a concrete gravity dam are discussed when subjected to the combined action of the penetration and explosion. In order to improve the structural performance of the mass concrete target to penetration and explosion loadings, high strength concrete material is selected as a preventive measure. Penetration processes and damage patterns of the mass target with normal and high strength concrete material are compared. Then, three internal explosion models are presented to investigate the influence of the initial penetration damage on the failure characteristics of the mass concrete target. The results show that the resistance of the mass target to the combined action of the penetration and explosion can be enhanced significantly by using the high strength concrete material. The initial penetration damage has a significant influence on the damage processes of the mass concrete target subjected to internal blast loading

How early can myocardial iron overload occur in Beta thalassemia major?

BACKGROUND: Myocardial siderosis is the most common cause of death in patients with beta thalassemia major(TM). This study aimed at investigating the occurrence, prevalence and severity of cardiac iron overload in a young Chinese population with beta TM. METHODS AND RESULTS: We analyzed T2* cardiac magnetic resonance (CMR), left ventricular ejection fraction (LVEF) and serum ferritin (SF) in 201 beta TM patients. The median age was 9 years old. Patients received an average of 13 units of blood per year. The median SF level was 4536 ng/ml and 165 patients (82.1%) had SF>2500 ng/ml. Myocardial iron overload was detected in 68 patients (33.8%) and severe myocardial iron overload was detected in 26 patients (12.6%). Twenty-two patients ≤10 years old had myocardial iron overload, three of whom were only 6 years old. No myocardial iron overload was detected under the age of 6 years. Median LVEF was 64% (measured by CMR in 175 patients). Five of 6 patients with a LVEF<56% and 8 of 10 patients with cardiac disease had myocardial iron overload. CONCLUSIONS: The TM patients under follow-up at this regional centre in China patients are younger than other reported cohorts, more poorly-chelated, and have a high burden of iron overload. Myocardial siderosis occurred in patients younger than previously reported, and was strongly associated with impaired LVEF and cardiac disease. For such poorly-chelated TM patients, our data shows that the first assessment of cardiac T2* should be performed as early as 6 years old