考虑零售商公平关切与广告努力水平的碳减排策略研究

随着环境质量的下降，企业和消费者的环保意识不断提高，越来越多的企业开始增加产品的碳减排投入并且通过低碳产品的广告宣传来吸引环保型消费者购买。假设碳减排制造商生产一类低碳产品/环保产品，本文研究由一个碳减排制造商、一个进行广告宣传的零售商和具有环保意识的消费者构成的一个二级供应链，通过构建零售商公平中性或公平关切时是否进行碳减排成本分担建立四个模型，分析消费者环保意识以及零售商分担的低碳成本比例和公平关切系数对供应链企业的影响。研究发现：①当消费者环保意识增加时，在构建的四个模型中，低碳产品的碳减排水平、广告努力水平、批发价格和零售价格均增加；②随着公平关切系数的增加，不论零售商是否承担碳减排成本，产品碳减排水平、广告努力水平、批发价格和零售价格逐渐降低；③在零售商承担一部分减排成本且不关注公平时，随着零售商承担的减排成本比例的增加，产品碳减排水平提高；当零售商关注公平且关注度较低时，随着零售商分担的低碳成本比例增加，产品碳减排水平减少；当零售商关注公平且关注度较高时，随着零售商分担的低碳成本比例增加，产品碳减排水平升高；④消费者环保意识的增加与零售商主动分担碳减排成本都会有利于环境质量的提高，然而零售商考虑公平关切不利于提高环境质量；如果零售商关注公平，分担碳减排成本是否有利于环境质量提高取决于零售商关注公平的程度。     

An Integrated Approach for Assessing the Impact of Large-Scale Future Floods on a Highway Transport System

The negative impact of climate change continues to escalate flood risk. Floods directly and indirectly damage highway systems and disturb the socioeconomic order. In this study, we propose an integrated approach to quantitatively assess how floods impact the functioning of a highway system. The approach has three parts: (1) a multi-agent simulation model to represent traffic, heterogeneous user demand, and route choice in a highway network; (2) a flood simulator using future runoff scenarios generated from five global climate models, three representative concentration pathways (RCPs), and the CaMa-Flood model; and (3) an impact analyzer, which superimposes the simulated floods on the highway traffic simulation system, and quantifies the flood impact on a highway system based on car following model. This approach is illustrated with a case study of the Chinese highway network. The results show that (i) for different global climate models, the associated flood damage to a highway system is not linearly correlated with the forcing levels of RCPs, or with future years; (ii) floods in different years have variable impacts on regional connectivity; and (iii) extreme flood impacts can cause huge damages in highway networks; that is, in 2030, the estimated 84.5% of routes between provinces cannot be completed when the highway system is disturbed by a future major flood. These results have critical implications for transport sector policies and can be used to guide highway design and infrastructure protection. The approach can be extended to analyze other networks with spatial vulnerability, and it is an effective quantitative tool for reducing systemic disaster risk.     

A Predictive Model for Survival of Escherichia coli O157:H7 and Generic E. coli in Soil Amended with Untreated Animal Manure

This study aimed at developing a predictive model that captures the influences of a variety of agricultural and environmental variables and is able to predict the concentrations of enteric bacteria in soil amended with untreated Biological Soil Amendments of Animal Origin (BSAAO) under dynamic conditions. We developed and validated a Random Forest model using data from a longitudinal field study conducted in mid-Atlantic United States investigating the survival of Escherichia coli O157:H7 and generic E. coli in soils amended with untreated dairy manure, horse manure, or poultry litter. Amendment type, days of rain since the previous sampling day, and soil moisture content were identified as the most influential agricultural and environmental variables impacting concentrations of viable E. coli O157:H7 and generic E. coli recovered from amended soils. Our model results also indicated that E. coli O157:H7 and generic E. coli declined at similar rates in amended soils under dynamic field conditions.The Random Forest model accurately predicted changes in viable E. coli concentrations over time under different agricultural and environmental conditions. Our model also accurately characterized the variability of E. coli concentration in amended soil over time by providing upper and lower prediction bound estimates. Cross-validation results indicated that our model can be potentially generalized to other geographic regions and incorporated into a risk assessment for evaluating the risks associated with application of untreated BSAAO. Our model can be validated for other regions and predictive performance also can be enhanced when data sets from additional geographic regions become available.     

成长品：数据驱动的企业与用户互动创新案例研究

现有产品创新理论聚焦于成品及其迭代,但大数据和人工智能等数字技术为产品形态的根本性变革提供了条件和可能。本文基于一家智能化广告公司的案例,提出一种新的产品形态--"成长品"的概念,主要回答3个问题:什么是成长品?成长品是如何成长的?成长品的创新逻辑是什么?研究获得以下结论:(1)成长品具有发展方向难以预测、即时反馈和即时调整3个主要特性;(2)成长品由要素解构与重组、成长性验证和多样化匹配3个关键过程形成,数据交互和智能算法构成其成长的重要条件;(3)成长品的创新主要基于生物演化的适应逻辑,即随用户需求的偏好差异和动态变化而实时调整,持续适应用户的需求。据此,本文提出一种数字经济时代新的产品形态二分法--成品与成长品,构建数据驱动的企业与用户互动创新的成长品三阶段成长模型,提出与现有企业与用户互动创新的决策逻辑和创生逻辑不同的第三种创新逻辑,即适应逻辑而形成理论创新。研究结论对数字经济时代的企业产品创新实践具有启示价值。     

互联网媒体企业员工离职行为影响机制研究——基于扎根理论分析

采用扎根理论方法,对某知名互联网媒体企业的47名离职人员进行深度访谈,构建离职行为影响机制模型。研究发现互联网媒体企业员工的离职过程是由行为态度、主观规范、行为控制和离职意向4个因素决定,且在影响程度和形式上有差异。研究为中国互联网媒体企业的员工离职管理提供了启示。     

More bounds for the Grundy number of graphs

A coloring of a graph \(G=(V,E)\) is a partition \(\{V_1, V_2, \ldots , V_k\}\) of V into independent sets or color classes. A vertex \(v\in V_i\) is a Grundy vertex if it is adjacent to at least one vertex in each color class \(V_j\) for every \(j<i\). A coloring is a Grundy coloring if every vertex is a Grundy vertex, and the Grundy number \(\Gamma (G)\) of a graph G is the maximum number of colors in a Grundy coloring. We provide two new upper bounds on Grundy number of a graph and a stronger version of the well-known Nordhaus-Gaddum theorem. In addition, we give a new characterization for a \(\{P_{4}, C_4\}\)-free graph by supporting a conjecture of Zaker, which says that \(\Gamma (G)\ge \delta (G)+1\) for any \(C_4\)-free graph G.     

电子供应链合作中IT使能合作优势的实现:基于关系观的实证研究

电子供应链的应用促使IT价值实现方式开始转移到企业间合作活动中。根据关系观(Relational view),本文确定了电子供应链合作中信息/知识共享惯例、治理以及互补式能力三种关系租的表征变量,研究了它们对焦点企业IT使能合作优势的影响。基于196家制造企业的实证研究发现,IS集成和伙伴信任的整合机制,以及电子供应链合作能力与合作敏捷性的匹配效应共同促进了IT使能合作优势的形成。具有较高敏捷性的焦点企业可以借助于合作能力获得更好的合作优势。     

Approximation algorithms for pricing with negative network externalities

We study the problems of pricing an indivisible product to consumers who are embedded in a given social network. The goal is to maximize the revenue of the seller by the so-called iterative pricing that offers consumers a sequence of prices over time. The consumers are assumed to be impatient in that they buy the product as soon as the seller posts a price not greater than their valuations of the product. The product’s value for a consumer is determined by two factors: a fixed consumer-specified intrinsic value and a variable externality that is exerted from the consumer’s neighbors in a linear way. We focus on the scenario of negative externalities, which captures many interesting situations, but is much less understood in comparison with its positive externality counterpart. Assuming complete information about the network, consumers’ intrinsic values, and the negative externalities, we prove that it is NP-hard to find an optimal iterative pricing, even for unweighted tree networks with uniform intrinsic values. Complementary to the hardness result, we design a 2-approximation algorithm for general weighted networks with (possibly) nonuniform intrinsic values. We show that, as an approximation to optimal iterative pricing, single pricing works fairly well for many interesting cases, such as forests, Erd?s–Rényi networks and Barabási–Albert networks, although its worst-case performance can be arbitrarily bad in general networks.     

Impact Factors and Risk Analysis of Tropical Cyclones on a Highway Network

Coastal areas typically have high social and economic development and are likely to suffer huge losses due to tropical cyclones. These cyclones have a great impact on the transportation network, but there have been a limited number of studies about tropical‐cyclone‐induced transportation network functional damages, especially in Asia. This study develops an innovative measurement and analytical tool for highway network functional damage and risk in the context of a tropical cyclone, with which we explored the critical spatial characteristics of tropical cyclones with regard to functional damage to a highway network by developing linear regression models to quantify their relationship. Furthermore, we assessed the network's functional risk and calculated the return periods under different damage levels. In our analyses, we consider the real‐world highway network of Hainan province, China. Our results illustrate that the most important spatial characteristics were location (in particular, the midlands), travel distance, landfalling status, and origin coordinates. However, the trajectory direction did not obviously affect the results. Our analyses indicate that the highway network of Hainan province may suffer from a 90% functional damage scenario every 4.28 years. These results have critical policy implications for the transport sector in reference to emergency planning and disaster reduction.     

产品保证策略研究现状与前景展望

当前,企业产品保证管理日益重要,如何制定经济、合理的保证策略已引起了业内人士的广泛关注。在国外,产品保证策略的研究已经形成较完整的体系,取得了丰富的研究成果,而国内相关研究尚处于起步阶段,仍有待进一步认识。通过对现有文献的整理,总结了保证策略的研究内容,并分类重点介绍各种不同条件下的保证策略制定方法,提出了保证策略今后的研究发展方向。通过对研究现状的总结及前景展望,不仅可以推进我国产品保证管理的研究工作,而且对我国企业借鉴国外先进的保证策略制定方法,提高保证管理水平具有重要的指导意义。