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21.
This paper examines the key factors that determine business traveler loyalty toward full-service airlines in China. Based on literature review and panel interview, ten airline attributes under three categories were derived: (a) operational factors: safety, punctuality, and aircraft; (b) competitive factors: frequency of flights, schedule, frequent flyer program, ticket price, and reputation; and (c) attractive factors: in flight food & drinks and in flight staff service. We surveyed 2000 Chinese business travelers on domestic flights, obtaining 462 usable questionnaires. Hierarchical regression analysis reveals that reputation, in-flight service, frequent flyer program, and aircraft have the greatest influence in driving airline loyalty.  相似文献   
22.
Wheat yields from reported performance test results are of economic importance to wheat producers, since their profits depend on selecting the optimal variety for their location. However, our data shows differences in absolute and relative wheat yields between commercial and public wheat breeding program's performance test data in Kansas. Newly available data are used to test if the difference in yields arose from potential selectivity bias, and to determine the contribution of private and public wheat breeding programs to varietal yield improvement during 2007–2012. Both Heckman selection models and multiple regression showed no statistical evidence of the potential presence of selectivity bias rather, managerial practices, agronomic conditions, field location, and inherent genetic traits of the seed variety were identify as the source of yield differences.  相似文献   
23.
The western Corn Belt region of the United States has become a hotspot for agricultural extensification and consequent land use and land cover changes. The goals of this research were to characterize geographic patterns of grassland loss resulting from cropland expansion in the eastern Dakotas, and to understand how these changes were associated with characteristics of individual farms and farm operators. We collected data on grassland conversion and other land use decisions through a mail survey of farm operators in North and South Dakota. Overall, 40% of respondents converted at least some grassland to cropland between 2004 and 2014, and the total acreage of converted grassland was equivalent to 5.1% of the surveyed farm acreage. Although most converted grassland acres (3.2% of farm acreage) were from land enrolled in the conservation reserve program (CRP), there were also substantial amounts of native grassland conversion (1.0%) and tame grassland conversion (0.9%). The total acreage of grassland conversion was more than four times larger than the acreage enrolled in CRP and other conservation programs. Different types of grassland conversion (e.g., native grassland versus CRP) were concentrated in different parts of the study region, and were spatially disjunct from the areas of highest conservation program enrollment. Larger farms were more likely than smaller farms to expand their cropland acreage and accounted for a disproportionate share of grassland conversion. Younger farm operators, higher levels of farm income, higher proportions of rented croplands, and marginal yields were also associated with cropland expansion and grassland conversion. Although CRP and other land retirement programs will remain important policy mechanisms for conservation in this region, they are not sufficient to maintain current levels of grassland cover and do not provide protection for native grasslands. Alternative conservation strategies and new agricultural policies are thus critically needed to maintain the ecosystem services provided by grasslands.  相似文献   
24.
围绕数据组织、数据的联动检索技术、Excel高级函数、Excel自定义函数、Excel VBA程序的开发过程,系统地建立了基于Excel的道路工程计算的框架模板。  相似文献   
25.
Using a natural experiment (the SEC's 2016 Tick Size Pilot Program), we investigate the effects of an increase in tick size on financial reporting quality. The tick size pilot program reduces algorithmic trading (AT) and increases fundamental investors’ information acquisition and trading activities. This in turn increases the scrutiny of managers’ financial reporting choices and reduces their incentives to engage in misreporting. Using a difference-in-differences research design, we find a significant decrease in the magnitude of discretionary accruals, a significant reduction in the likelihood of just meeting or beating analysts’ forecasts, and a marginally significant decrease in restatements for the treated firms in the pilot program. Furthermore, we find that the change in financial reporting quality is concentrated in treated firms experiencing decreases in AT and increases in information acquisition activities. We also find that the mispricing of accruals is significantly lower for treated firms. Taken together, our results suggest that an increase in tick size has a causal effect on firms’ financial reporting quality.  相似文献   
26.
超奈奎斯特(Faster-than-Nyquist,FTN)速率传输可以有效提高频谱效率,但这种非正交传输方式引入的严重码间串扰相应提高了接收端的处理难度。针对该问题,设计了一种基于循环成块传输的低复杂度检测算法。最优检测被建模为无约束的二元二次规划(Boolean Quadratic Program,BQP)问题,为了求解该NP-hard问题,采用无穷范数约束松弛原问题的非凸可行解集,并基于次梯度下降法提出松弛问题的有效优化算法。数值仿真结果表明,所提算法在误比特率(Bit Error Rate,BER)性能上优于频域均衡,且在可接受的性能损失范围内算法执行效率远高于理论最优的最大似然序列估计(Maximum Likelihood Sequence Estimation,MLSE)。  相似文献   
27.
为解决目前集装箱配积载中尚需结合人工经验来进行箱位选配的问题,通过研究集装箱船配积载前重心距基线高,运用集装箱船初稳性高度计算原理,结合集装箱船的结构特点,建立集装箱船初稳性高度优化模型。运用交互式的线性和通用优化求解器编写程序,其研究成果将为实现集装箱船自动化配积载目标提供理论基础。  相似文献   
28.
This study examines the relationships among the perceived value of a loyalty program, customer satisfaction with a loyalty program, affective commitment, switching barriers, and customer brand loyalty in the hotel context. An online survey method with a quantitative approach was used. Our results from a structural equation model revealed that the perceived value of a loyalty program is essential in the formation of customer brand loyalty. Lastly, findings from an indirect analysis showed that affective commitment and switching barriers mediated the relationship between the perceived value of a loyalty program and customer brand loyalty. Overall, our research will help researchers and practitioners demonstrate to the industry that the loyalty program is a crucial strategy for customer loyalty and helps develop competitive loyalty programs for success.  相似文献   
29.
曹二方 《价值工程》2015,34(16):89-91
新建湘桂铁路于DK233+503处下穿全兴高速公路,原设计采用顶进框架桥方案。通过对安全质量的可控性、经济、工期等方面进行综合比选,取消顶进框架桥,变更为公路箱梁桥上跨铁路方案,采用分幅封道、分幅施工,既安全快速地穿过全兴高速公路,又创造了良好的经济效益和社会效益,为类似的工程提供了一定的参考价值。  相似文献   
30.
现代制造企业对高职院校学生的职业技能要求越来越高,开展课程教学改革,实施理实一体化教学非常重要。数控编程与加工课程是数控技术专业核心课程,开展基于工作过程的数控编程与操作课程学习情境设计,实施理实一体化教学,有利于提高学生职业技能的培养。  相似文献   
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