Bear Factor and Hedge Fund Performance

We show that a simple and intuitive variable, the return of a bear spread portfolio orthogonalized with respect to the market (H-Bear factor), can serve as a new benchmark for explaining the cross-section of hedge fund returns. Low H-Bear exposure funds (bear risk insurance sellers) outperform high H-Bear exposure funds (bear risk insurance buyers) by 0.58% per month on average, outperform even during market crashes, but underperform when bear market risk materializes. Overall, we identify a new risk dimension that affects hedge fund performance, and we show that this risk factor is distinct from the already popular realized tail risk

A model-based clinically-relevant chemotherapy scheduling algorithm for anticancer agents

Chemotherapy is the most commonly employed method for systemic cancer treatment of solid tumors and their metastases. The balance between cancer cell elimination and host toxicity minimization remains a challenge for clinicians when deploying chemotherapy treatments. Our approach explicitly incorporates treatment-induced toxicities into the schedule design. As a case study, we synthesize administration schedules for docetaxel, a widely used chemotherapeutic employed as a monoagent or in combination for the treatment of a variety of cancers. The primary adverse effect of docetaxel treatment is myelosuppression, characterized by neutropenia, a low plasma absolute neutrophil count (ANC). Through the use of model-based systems engineering tools, this thesis provides treatment schedules for docetaxel and its combination therapies that reduce toxic side effects and improve patient outcomes. The current algorithm employs models of tumor growth, drug pharmacokinetics, and pharmacodynamics for both anticancer effects and toxicity, as characterized by ANC. Also included is a toxicity-rescue therapy, with granulocyte colony stimulating factor (G-CSF) that serves to elevate ANC. The single-agent docetaxel chemotherapy schedule minimizes tumor volume over a multi-cycle horizon, subject to toxicity and logistical constraints imposed by clinical practice.This single-agent chemotherapy scheduling formulation is extended to combination chemotherapy using docetaxel-cisplatin or docetaxel-carboplatin drug pairs. The two platinum agents display different toxicities, with cisplatin exhibiting kidney function damage and carboplatin demonstrating the same myelosuppression effects as docetaxel. These case studies provide two different challenges to the algorithm: (i) cisplatin scheduling significantly increases the number of variables and constraints, thereby challenging the computational engine and formulation; (ii) carboplatin's overlapping toxicity tests the ability of the algorithm to schedule drugs with different mechanisms of action (they act in different phases of the cellular growth cycle) with the same toxic side effects. The simulated results demonstrate the algorithms flexibility, in scheduling both docetaxel and cisplatin or carboplatin treatments for effective tumor elimination and clinically acceptable toxicties. Overall, a clinically-relevant chemotherapy scheduling optimization algorithm is provided for designing single agent and combination chemotherapies, when toxicity and pharmacokinetic/pharmacodynamic information is available. Furthermore, the algorithm can be extended to patient-specfic treatment by updating the pharmacokinetic/pharmacodynamic models as data are collected during treatment

Teoretické studium vlastností 3D a 2D zeolitů

Zeolites have been widely used in many different fields including catalysis, adsorption and separation, ion exchange, or gas storage. Conventional zeolites have three- dimensional (3D) structures with microporous channel system; typical pore sizes are well below 1 nanometer, therefore, diffusion limitation plays important role in many process and bulkier reactants (or products) cannot enter (or leave) the zeolite channel system. Two-dimensional (2D) zeolites prepared in last years can lift all diffusion limitation and they thus offer a very attractive alternative to conventional 3D zeolites. 2D zeolites attracted considerable attention on the experimental side; however, understanding of 2D zeolites based on computational investigation or on a combination of experimental and computational investigation is limited. A motivation for the computational work presented here is to improve our understanding of properties of 2D zeolites based on computational investigation. The originality of the research presented herein is in the strategy: we carried out systematic investigation of properties of corresponding 2D and 3D zeolites and we focus on the identification of similarities and differences. The most important zeolite properties, i.e., presence of Brønsted and Lewis acid sites, are investigated. A number of...Zeolity jsou široce využívány v řadě oblastí včetně katalýzy, adsorpcí a separací, iontových výměn a ukládání plynů. Běžné zeolity mají trojrozměrnou (3D) strukturu obsahující systém mikroporézních kanálů. Typická velikost těchto kanálů je pod 1 nm, v důsledku čehož je řada procesů limitována rychlostí difúze a větší reaktanty (produkty) nemohou vůbec vstoupit (opustit) do kanálového systému. Dvojrozměrné (2D) zeolity připravené v posledních letech mohou zmírnit nebo zcela eliminovat problémy spojené s difúzí a představují velmi zajímavou alternativu k běžným 3D zeolitům. 2D zeolity byly intenzivně zkoumány v posledních letech zejména experimentálně, zatímco porozumění jejich vlastností na základě teoretických výpočtů či na základě kombinace experimentu a teorie je zatím značně omezené. Práce zde předkládaná je motivována snahou vyjasnit vlastnosti 2D zeolitů na základě výpočetní studie. Originalita našeho výzkumu je ve zvolené strategii - na základě systematického výzkumu vlastností 2D a korespondujících 3D zeolitů chceme nalézt a pochopit podobnosti a rozdílnosti mezi 3D a 2D zeolity. Soustředíme zejména na studium nejvýznamnějších vlastností zeolitů, tedy na popis Brønstedovské a Lewisovské kyselosti. Zabýváme se studiem různých charakteristik kyselých center v zeolitech a zejména takových...Department of Physical and Macromolecular ChemistryKatedra fyzikální a makromol. chemieFaculty of SciencePřírodovědecká fakult

Context dependent fuzzy modelling and its applications

Fuzzy rule-based systems (FRBS) use the principle of fuzzy sets and fuzzy logic to describe vague and imprecise statements and provide a facility to express the behaviours of the system with a human-understandable language. Fuzzy information, once defined by a fuzzy system, is fixed regardless of the circumstances and therefore makes it very difficult to capture the effect of context on the meaning of the fuzzy terms. While efforts have been made to integrate contextual information into the representation of fuzzy sets, it remains the case that often the context model is very restrictive and/or problem specific. The work reported in this thesis is our attempt to create a practical frame work to integrate contextual information into the representation of fuzzy sets so as to improve the interpretability as well as the accuracy of the fuzzy system. Throughout this thesis, we have looked at the capability of the proposed context dependent fuzzy sets as a stand alone as well as in combination with other methods in various application scenarios ranging from time series forecasting to complicated car racing control systems. In all of the applications, the highly competitive performance nature of our approach has proven its effectiveness and efficiency compared with existing techniques in the literature

Efficient Generation of Coherent Stokes Field in Hydrogen Gas-Filled Hollow Core Photonic Crystal Fibres

In this paper, we study of the coherent Stokes generation in a transient Raman regime by Hydrogen gas-filled hollow-core photonic crystal fibres (HC-PCFs) configuration. The temporal and spatial evolution of the pump and Stokes field envelopes as well as the coherence and population inversion is numerically observed. The influence of the pump pulse width and gas pressure on the energy exchange along fiber and Stokes generation efficiency is investigated

STAKEHOLDER INVOLVEMENT IN DESTINATION MARKETING: A NETWORK ANALYSIS OF TWO DESTINATIONS IN VIETNAM

Purpose –This paper aims to identify the stakeholders involved in tourism destination marketing networks. The involvement and collaboration of multiple individuals and organisations is widely recognised in destination marketing to promote a destination. Internal stakeholders of a destination and their collaboration are frequently studied in destination marketing research, but little attention is paid to the involvement of external stakeholders. Design/Methodology/Approach – Quantitative social network analysis is an important approach to understanding stakeholder connections and roles in tourism destinations. In this paper, this analysis was conducted using primary data collected from social network surveys in Da Nang and Hue, two local destinations in central Vietnam. Sixty-nine questionnaires were collected in Da Nang, and 60 questionnaires in Hue. The network data were each analysed separately using UCINET software. Findings – The results show the involvement of different stakeholders in marketing activities in these local destinations. Most of the marketing networks of Da Nang and Hue consist of business units. While the Da Nang marketing network focuses on critical stakeholders and fundamental business firms with strong financial resources and big brands, the Hue marketing network includes more diverse stakeholders and more significant participation of small and medium local firms. Originality of research – This research found the participation of national and international stakeholders located outside the two destinations studied in their marketing network. Their involvement was identified through their collaborative relationships with the DMOs and internal stakeholders of the two destinations to promote the destinations nationally and internationally

An Investigation of Intercultural Teaching and Learning in Tertiary EFL Classrooms in Vietnam

Intercultural competence has become an important goal of foreign language education in response to the need for learners to function effectively in an increasingly multicultural world. Language and culture are seen as interwoven and inseparable components and therefore learning a foreign language inevitably means learning about other ways of being and behaving. Many foreign language programmes around the world, particularly in North America, Europe, Australia and New Zealand, have adopted an intercultural pedagogy which seeks to integrate into the language teaching experience opportunities for developing intercultural competence for language learners. This study investigates intercultural teaching and learning in tertiary EFL classrooms in Vietnam, a context in which intercultural approaches to language teaching and learning have not been widely considered. The study consisted of three phases. The first phase involved a curriculum review in which I critically evaluated the extent to which culture and culture learning are represented in the curriculum frameworks for tertiary EFL programmes and in the national education policy on foreign language education in Vietnam. The findings showed that the importance of culture and culture learning is not emphasised, and the designation of culture to separate culture courses establishes a separate status, construct and treatment of culture and culture learning in the EFL programmes. In the second phase of the study, I analysed the perceptions of fourteen Vietnamese EFL teachers and two hundred Vietnamese EFL students on culture in language teaching and learning, and their classroom practices. The findings indicated that the teachers' beliefs about culture teaching revealed a predictable priority for teaching language rather than culture. Their culture teaching practices were greatly influenced by their perceptions and beliefs regarding culture in language teaching. The students also treated culture as a subordinate priority in language learning. Overall, they found culture learning beneficial for their language learning and supported the teachability of language and culture in EFL classes. Both the teachers and students identified a number of constraints that restricted their opportunities and motivation to engage in teaching and learning culture. The third phase of the study involved an empirical study investigating the effect of adopting an intercultural stance in English speaking lessons on the development of the learners' intercultural competence. Over a nine-week teaching period, eighteen English speaking lessons (90 minutes / lesson / week) for two equivalent, intact classes (seventy-one students) were observed. For one class, the lessons were adapted to reflect the principles of intercultural language learning. For the other, no changes were made. The results showed that the intercultural competence of learners in the intercultural class increased by significantly more than that of learners in the standard class. In particular, the students in the intercultural class were able to better articulate ethnorelative awareness and attitudes towards their home culture and the target culture. The findings also showed that the reflective journal was an effective tool to assess learners' process of acquiring intercultural competence, particularly affective capacities that are not easy to evaluate by other means. Overall, the study provided evidence for the feasibility of intercultural teaching and learning in tertiary EFL classrooms in the Vietnamese context. It also showed that intercultural teaching and learning cultivated learners' affective capacities which are often overlooked in the EFL classroom. It is hoped that the study can inform the work of curriculum designers, education policy-makers as well as EFL teachers and students for the implementation of intercultural language teaching and learning in Vietnam and elsewhere

Context dependent fuzzy modelling and its applications

Fuzzy rule-based systems (FRBS) use the principle of fuzzy sets and fuzzy logic to describe vague and imprecise statements and provide a facility to express the behaviours of the system with a human-understandable language. Fuzzy information, once defined by a fuzzy system, is fixed regardless of the circumstances and therefore makes it very difficult to capture the effect of context on the meaning of the fuzzy terms. While efforts have been made to integrate contextual information into the representation of fuzzy sets, it remains the case that often the context model is very restrictive and/or problem specific. The work reported in this thesis is our attempt to create a practical frame work to integrate contextual information into the representation of fuzzy sets so as to improve the interpretability as well as the accuracy of the fuzzy system. Throughout this thesis, we have looked at the capability of the proposed context dependent fuzzy sets as a stand alone as well as in combination with other methods in various application scenarios ranging from time series forecasting to complicated car racing control systems. In all of the applications, the highly competitive performance nature of our approach has proven its effectiveness and efficiency compared with existing techniques in the literature

An efficient cuckoo-inspired meta-heuristic algorithm for multiobjective short-term hydrothermal scheduling

This paper proposes an efficient Cuckoo-Inspired Meta-Heuristic Algorithm (CIMHA) for solving multi-objective short-term hydrothermal scheduling (ST-HTS) problem. The objective is to simultaneously minimize the total cost and emission of thermal units while all constraints such as power balance, water discharge, and generation limitations must be satisfied. The proposed CIMHA is a newly developed meta-heuristic algorithm inspired by the intelligent reproduction strategy of the cuckoo bird. It is efficient for solving optimization problems with complicated objective and constraints because the method has few control parameters. The proposed method has been tested on different systems with various numbers of objective functions, and the obtained results have been compared to those from other methods available in the literature. The result comparisons have indicated that the proposed method is more efficient than many other methods for the test systems in terms of total cost, total emission, and computational time. Therefore, the proposed CIMHA can be a favorable method for solving the multi-objective ST-HTS problems