机载传感器无引导搜索策略研究

针对机载传感器搜索任务,将无引导搜索问题分为搜索区域目标出现概率未知和已知两种情况进行了讨论。在搜索区域仅有一个目标和忽略传感器搜索视场切换的前提假设下,在搜索时间最短的要求下,提出了一种最优搜索策略,即任一视场的搜索次数与该视场中目标出现概率的平方根成正比。并通过仿真实例表现了该搜索策略：未知目标出现概率的情况下是一种顺序搜索,而已知目标出现概率的情况下是优先、多次搜索目标出现概率较大视场的同时,还无遗漏的兼顾搜索其他视场。该策略使传感器尽快满足任务要求,缩减工作时间。     

适用于宽带网络波形的基于定价策略的时隙选择

针对宽带网络波形（Wideband Networking Waveform,WNW）的多信道二维时频资源,以减小网络资源浪费为优化目标,提出了一种基于定价策略的时隙选择方法（Pricing Strategy Based Slot Selection,PSSS）。该方法通过接纳控制保障资源分配的公平性,采用对偶优化建模与椭圆搜索法实现最优的时隙选择。理论分析证明该方法能够在多项式级别时间复杂度内搜索到时隙选择的最优解。仿真结果表明,提出的PSSS算法通过较低资源浪费获得了较低的容量冗余度,能够有效地解决WNW多信道网络的时隙选择问题。     

The airfare pricing and seat allocation problem in full-service carriers and subsidiary low-cost carriers

This study investigates the competitive market situation in the air transport industry considering full-service carriers (FSC), subsidiary low-cost carriers (LCC) and rival LCCs on the flight-leg level while subsidiary LCCs are established by FSCs against rival LCCs to keep the market share and to make more profit. It is assumed that the demand of economy class for each airline follows a known distribution, and the mean value of that distribution is a function of its airfare and the airfare differences with other airlines. In addition, no-shows and cancellations are introduced to reflect a real situation. Based on this situation, a mathematical model is developed to derive efficient airfare pricing and seat allocation for each airline for maximizing the profit sum of both FSCs and subsidiary LCCs using a repeated game. A repeated game model integrated with a Tabu search algorithm and an EMSR based heuristic is suggested to deal with the proposed repeated game. A numerical example is provided to validate the model and solution procedure with hypothetical system parameter values under two kinds of market situations that show before and after the emergence of subsidiary LCCs.     

Sibling gender and wage differences

Family influences on economic performance are investigated. In particular, sibship sex composition is related to hourly wages using data from the National Longitudinal Survey of Youth 1979. The wages of men are increasing in the proportion of siblings who are brothers, but the wages of women are insensitive to sibling gender. Nonwage outcomes are generally unaffected. Contrasts by age structure and demographic group are also presented. The analysis addresses econometric challenges like the endogeneity of fertility and selection into the workforce. In addition, mechanisms such as labour market interactions, human capital investment and role model effects are documented. A questionnaire on job search indicates a same-gender bias in the use of brothers and sisters in obtaining employment. Developmental and psychological assessments suggest that brothers may be associated with worse childhood home environments and more traditional family attitudes among women. The findings are policy relevant and contribute to an understanding of gender differences and earnings inequality.     

Welfare Cost of Fluctuations When Labor Market Search Interacts with Financial Frictions

We study the welfare costs of business cycles in a search and matching model with financial frictions. The model replicates the volatility on labor and financial markets. Business cycle costs are sizable. Indeed, the interactions between labor market and financial frictions magnify the impact of shocks via (i) a credit multiplier effect and (ii) an endogenous wage rigidity inherent to financial frictions. In addition, in a nonlinear framework, large welfare costs of fluctuations are explained by the high average unemployment and the low job finding rates with respect to their deterministic steady‐state values.     

A picture is worth a thousand words: The role of a cover photograph on a travel agency’s online identity

Online travel agencies (OTAs) allow lodging businesses to select one cover photograph to represent itself on the OTA site. The cover photograph plays a crucial role for attracting customers’ attention from among alternatives, and lure viewers to view the webpage with detailed information. The present study investigates how the content of a business’ cover photograph on OTAs’ sites influences customers’ behavior when searching for information. The content of a cover photograph may fall within five categories according to attributes: façade, type of place, room amenities, scenery, and property amenities. Only façade and property amenities have positive impacts on customers’ viewing times of the webpages with the detailed information of businesses. In contrast, scenery has a negative influence on customers’ viewing times. The results of the study contribute, theoretically and methodologically, to OTAs’ knowledge base and can assist practitioners’ identification of effective cover photographs.     

Search within or beyond the industrial cluster? The effect of perceived competition and knowledge base tacitness on strategic location choices of external knowledge search

ABSTRACT

From a knowledge-based perspective, this paper highlights the need for a framework linking perceived competition of the industry and firms’ strategic location choices of external knowledge search and examines whether the perceived competition increases the propensity of cluster firms to search more widely from extra-cluster knowledge sources than intra-cluster knowledge sources. Furthermore, we emphasise that cluster firms with varying degrees of tacitness in their knowledge base might respond to such competition differently when conducting external knowledge search activities. Using a sample of 310 cluster firms in the Zhejiang Province of China, we find that the cluster firm would increase the propensity for more geographic boundary-spanning search relative to local search while under the pressure of competition. Moreover, the positive relationship between perceived competition and the propensity towards geographic knowledge search is weaker when the tacitness of the cluster firm’s knowledge base is higher. The findings contribute to the understanding of the relationship between competition and the choice of location strategies in external knowledge search.     

Masterful Meisters? Voluntary Certification and Quality in the German Crafts Sector

Voluntary certification systems potentially reduce search costs in markets with imperfect information. Service markets with many heterogeneous firms – such as the crafts market – are prone to information imperfections and can therefore potentially benefit from such informational mechanisms. We examine if the Meister qualification in the German crafts sector improves service quality as perceived by consumers. We find a significant and positive relationship between the Meister title and consumer ratings and conclude that the certificate is a credible sign of quality.     

Optimising flight connection times in airline bank structure through Simulated Annealing and Tabu Search algorithms

In hub and spoke airline networks, flight arrivals and departures generally have a bank structure to increase connections among spoke cities through a hub airport in order to provide cheaper service for higher volumes of air traffic. In this study, we introduce the airline bank optimisation problem with a novel mathematical model for improving flight connection times. The mathematical model aims to minimise the total connection times for transfer passengers and generates flight schedules regarding slot capacities in the hub airports. Since the problem is a combinatorial optimisation problem NP-hard and computational complexity increases rapidly for real-world problems, we employ the simulated annealing and the tabu search algorithms to achieve better solutions in a reasonable time. We generate sub-problems using real-world data and investigate the effectiveness of the algorithms. Finally, we present the results of a real case study of a Turkish airline company which has a hub airport connecting the flights between Middle Eastern and European cities.     

The interaction between reputation and information search: Evidence of information avoidance and confirmation bias

This paper investigates how the valence of reputation affects the information search, and how the outcome of the search can result in a reevaluation of reputation. The protocol uses a digital version of the Information Display Board (IDB) to examine the dynamics of information search and reputation building. A sample of 1811 respondents was asked about their perceptions of the reputation of specific performing arts events, pre- and post-information search. The findings provide evidence of a confirmation bias (between positive information and the information search), and support information avoidance theories. Specifically, our results show that prior reputation only affected the online information search for consumers with no opinion, or with a positive opinion of a show's reputation. Furthermore, the information search only modifies reputation when consumers have no prior opinion.