纸浆漂白成本在线计算模型构建及应用研究

能源和化学品价格的快速上涨使得制浆工作者尤为关注如何降低纸浆漂白成本。本研究构建了纸浆漂白成本的在线计算模型，并应用于典型ECF漂白技术（D₀EpPD₁），同时系统分析了影响纸浆漂白成本的主要因素和该模型在漂白工艺条件优化过程中的应用效果。研究发现，化学品成本是影响漂白成本的最主要因素，其次是能源成本、废水处理成本、清水成本；化学品中ClO₂用量对纸浆漂白成本的影响最大，其次是H₂O₂用量，NaOH用量影响最小；能源成本中蒸汽用量对纸浆漂白成本影响最大；而清水成本和废水处理成本影响最小；通过对化学品用量、漂白温度等漂白工艺条件的调整可降低纸浆漂白成本；该模型可实现对漂白工艺条件的优化或能源及化学品价格变化后纸浆漂白成本的在线预测，也是实现纸浆漂白系统全局优化、进一步降低漂白成本的基础。     

连续管疲劳寿命预测软件开发及应用

连续管在作业过程中,复杂的周期性载荷作用、腐蚀、机械损伤、制造缺陷和人为误操作等都会导致连续管寿命的缩短。为此,基于Qt平台、疲劳寿命理论和国内外大量经验数据开发出了连续管疲劳寿命预测软件。通过该软件计算分析了连续管弯曲半径、壁厚和内压等对其疲劳寿命的影响,并进行了可行性验证。分析结果表明:该软件能够有效地计算出连续管疲劳寿命值;连续管内部压力的增大使其疲劳寿命的缩短由快速到缓慢,当内压增大到一定值时,连续管基本失去承载能力;选择合适的滚筒尺寸可以延长连续管的使用寿命;建议选用壁厚较大或者变壁厚的连续管。该软件的开发对连续管在工程中的应用和安全评估具有重要的指导意义。     

基于光纤-无线网络的协同计算卸载算法

随着无源光网络的发展,光纤-无线网络能同时支持集中式云和边缘云计算技术,成为一种具有发展前景的网络结构。但是,现有的基于光纤-无线网络的任务协同计算卸载研究主要以最小化移动设备的能耗为目标,忽略了实时性高的任务的需求。针对实时性高的任务,提出了以最小化任务的总处理时间为目标的集中式云和边缘云协同计算卸载问题,并对其进行形式化描述。同时,通过将该问题归约为装箱问题,从而证明其为NP难解问题。提出一个启发式协同计算卸载算法,该算法通过比较不同卸载策略的任务处理时间,优先选择时间最短的任务卸载策略。同时,提出一个定制的遗传算法,获得一个更优的任务卸载策略。实验结果表明,与现有的算法相比,本文提出的启发式算法得到的任务卸载策略平均减少4.34%的任务总处理时间,而定制的遗传算法的卸载策略平均减少18.41%的任务总处理时间。同时,定制的遗传算法的卸载策略与本文提出的启发式算法相比平均减少14.49%的任务总处理时间。     

Perceived density,a further attribute of color,revealed by the colors favored in Japan

Colors can be characterized by three main attributes: hue, value, and saturation. But colors also exhibit other phenomenological qualities. In this study, we identify one such secondary attribute of color: perceived density. We discuss the prevalence of dense colors in Japan starting from the “48 Teas and 100 Mice” colors of the Edo period, and develop the concept of perceived density through this aspect of Japanese color preference. When vivid colors were forbidden to commoners during the Edo period, subtle variations of brownish and grayish colors were created. These colors with base tones were not salient, yet they looked dense. Muted colors with paradoxical richness are still common in Japan today. Japanese commodity design often uses muddy colors with white or gray undertones, and deep colors with black undertones. Together they form distinct groupings of relatively dense color. The perceived density of color corresponds to how dense and filled, or thin and airy a color appears. Colors of higher perceived density appear to be more packed and to have mass. Perceived density of color is unusual in that it does not have a monotonic relationship with one of the primary perceptual attributes. High apparent density is observed in a central region of an equi‐hue plane where value or saturation are at intermediate values. We consider two possible explanations of how high values of density can coincide with middling values of value and saturation: characteristics of the spectral reflectance curves, or the complexity of the neural signals that underlie the emergent property.     

Multi-key FHE without ciphertext-expansion in two-server model

López-Alt et al.(STOC12)put forward a primitive called multi-key fully homomorphic encryption(MKFHE),in which each involved party encrypts their own data using keys that are independently and randomly chosen whereby arbitrary computations can be performed on these encrypted data by a final collector.Subsequently,several superior schemes based on the standard assumption(LWE)were proposed.Most of these schemes were constructed by expanding a fresh GSW-ciphertext or BGV-ciphertext under a single key to a new same-type ciphertext of the same message under a combination of associated parties’keys.Therefore,the new ciphertext’s size grew more or less linearly with an increase in the number of parties.In this paper,we proposed a novel and simple scheme of MKFHE based on LWE without increasing the size of the ciphertext in the two non-collusion server model.In other words,each party first independently shares their own data between two servers and each server only needs a one-round communication with another to construct a ciphertext of the same plaintext under a sum of associated parties’keys.Our new ciphertext under multiple keys has the same size as that of the original one with only one-round communication between two servers.The communication complexity is O(kmlogq)-bit,where k is the number of input ciphertexts involved,m is the size of a GSW-ciphertext and q is a modulus.In conclusion,we proved that our scheme is CPA-secure against semi-honest adversaries.     

化学工程中的介尺度科学与虚拟过程工程：分析与展望

传统的过程工程研发具有周期长、风险大、费用高等特点,制约了过程工业的快速发展。解决这一问题应从介尺度科学和虚拟过程工程两方面入手。首先,这一问题的科学根源在于化学和过程工程中的多尺度和多层次结构;而介尺度作为其中的难点和瓶颈,目前的认识还比较有限。认识和理解介尺度复杂性对研究材料的构效关系、反应器混合与传递、系统集成等具有重要意义。只有实现了流动、传递和反应在介尺度的耦合,才能够准确理解、预测和调控多相反应器中的多尺度结构。另一方面,基于介尺度科学的虚拟过程工程将成为一种全新的过程研发模式,不仅可以大幅度缩短过程放大周期,也使产品精细化成为可能。虚拟过程工程是连接介尺度科学与新技术新工艺开发的桥梁,它是一种实体化、功能化的开发和分析工具及知识库,将实验室成果快速应用于过程开发,将大幅提升我国过程工业对核心技术的研发能力。传统的理论和超级计算尚不足以支撑虚拟过程工程,而介尺度科学则为虚拟过程工程带来前所未有的发展机遇。虚拟过程工程涉及多学科交叉,不仅是模拟计算人员的任务,也是实验室和过程研发人员共同的责任;它甚至在未来可以与云计算相结合,使过程工程进入大数据时代。     

烟囱圆形板式基础计算分析

玻璃厂窑炉烟囱因其受风荷载、地震荷载以及筒身的附加弯矩等作用,其基础设计尤为重要,文章讨论了钢筋混凝土烟囱应用最为广泛的圆形板式基础的计算方法。     

焦炉气甲烷化过程模拟计算顺序的确定

序贯模块法广泛应用于化工过程流程模拟。对于具有回路的化工过程,其计算顺序的确定是很重要的问题。本文针对有回路的焦炉气甲烷化流程进行了分析,确定了其模拟计算时的计算顺序,对焦炉气甲烷化流程的研究具有很好的参考价值。     

某屋架下弦屈曲的检测分析

某在建厂房因柱基位移导致屋架下弦屈曲,通过现场检测和结构计算,分析结构变形的原因,提出结构处理方案.