Commonly encountered in cold chain logistics, third-party distribution firms are required to deliver temperature-sensitive food products to various retailers with two kinds of time-window constraints: (1) the delivery service must begin within the time windows imposed by the retailers (called node time windows) and (2) each vehicle route is available only in a predefined time interval prescribed by the government (called arc time windows). We study the effects of the retailer time window type (i.e., density of the node time-window constraints) and other cost-related factors on a distribution firm’s legitimacy choice (i.e., the firm chooses to either comply with or violate the governmental time-window policy), food quality, and pollutant emissions in the urban environment. We model the problem as an intractable vehicle routing problem with node and arc time windows and develop a genetic algorithm to tackle it. We conduct a case study to generate the managerial insights on dealing with time windows. We find that the governmental time windows will increase the distribution cost. The governmental time windows has a negative effect on pollutant emissions while showing a positive effect on food safety. Given governmental time windows, a higher demand for node time windows will result in more governmental time-window violations or lower vehicle load factor, which depends on the vehicle fixed cost, fuel price, and government penalty.

中文翻译：

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冷链配送：如何处理节点和弧时间窗口？

在冷链物流中经常遇到的情况是，第三方分销公司需要将温度敏感的食品交付给各种零售商，有两种时间窗口限制：（1）交付服务必须在零售商规定的时间窗口内开始（称为节点时间窗口）和（2）每条车辆路线仅在政府规定的预定义时间间隔内可用（称为弧时间窗口）。我们研究了零售商时间窗口类型（即节点时间窗口约束的密度）和其他成本相关因素对分销公司合法性选择（即，公司选择遵守或违反政府时间-窗口政策）、食品质量和城市环境中的污染物排放。我们将该问题建模为具有节点和弧时间窗口的棘手车辆路径问题，并开发了一种遗传算法来解决它。我们进行了一个案例研究，以产生有关处理时间窗口的管理见解。我们发现政府时间窗口会增加分销成本。政府时间窗口对污染物排放有负面影响，同时对食品安全有积极影响。给定政府时间窗口，对节点时间窗口的更高需求将导致更多的政府时间窗口违规或更低的车辆负载因子，这取决于车辆固定成本、燃料价格和政府罚款。我们发现政府时间窗口会增加分销成本。政府时间窗口对污染物排放有负面影响，同时对食品安全有积极影响。给定政府时间窗口，对节点时间窗口的更高需求将导致更多的政府时间窗口违规或更低的车辆负载因子，这取决于车辆固定成本、燃料价格和政府罚款。我们发现政府时间窗口会增加分销成本。政府时间窗口对污染物排放有负面影响，同时对食品安全有积极影响。给定政府时间窗口，对节点时间窗口的更高需求将导致更多的政府时间窗口违规或更低的车辆负载因子，这取决于车辆固定成本、燃料价格和政府罚款。