Aristotle Said “Happiness is a State of Activity” — Predicting Mood Through Body Sensing with Smartwatches

We measure and predict states of Activation and Happiness using a body sensing application connected to smartwatches. Through the sensors of commercially available smartwatches we collect individual mood states and correlate them with body sensing data such as acceleration, heart rate, light level data, and location, through the GPS sensor built into the smartphone connected to the smartwatch. We polled users on the smartwatch for seven weeks four times per day asking for their mood state. We found that both Happiness and Activation are negatively correlated with heart beats and with the levels of light. People tend to be happier when they are moving more intensely and are feeling less activated during weekends. We also found that people with a lower Conscientiousness and Neuroticism and higher Agreeableness tend to be happy more frequently. In addition, more Activation can be predicted by lower Openness to experience and higher Agreeableness and Conscientiousness. Lastly, we find that tracking people’s geographical coordinates might play an important role in predicting Happiness and Activation. The methodology we propose is a first step towards building an automated mood tracking system, to be used for better teamwork and in combination with social network analysis studies.     

页岩气低伤害超临界CO2凝胶压裂液研究

针对常规水压裂液会对页岩造成伤害，容易产生水锁，不易返排，还造成水资源消耗和污染环境等问题，制备了低伤害二氧化碳凝胶压裂液。将自备的F2EU和F4EU增稠剂加入到超临界CO₂基液中，探究两种增稠剂的加入量对CO₂凝胶压裂液黏度的影响，综合考虑成本与效果，优选了2%的F4EU增稠剂，可将CO₂的黏度增至15.4 mPa·s。研究了温度、压力以及剪切速率对凝胶压裂液黏度的影响。实验结果表明，随着温度升高黏度总体降低，但中间出现一个短暂升高阶段；随着压力上升压裂液黏度增加；随着剪切速率的增加压裂液黏度下降，属于一种典型的剪切变稀的假塑性流体。F4EU超临界CO₂凝胶压裂液的平均伤害率为1.39%，远远小于常规压裂液对岩芯的伤害率。实验表明，F4EU超临界CO₂凝胶压裂液在页岩气压裂开采中具有良好的应用前景。     

EVOKE: A Value-Driven Concept Selection Method for Early System Design

The development of new technologically advanced products requires the contribution from a range of skills and disciplines, which are often difficult to find within a single company or organization. Requirements establishment practices in Systems Engineering (SE), while ensuring coordination of activities and tasks across the supply network, fall short when it comes to facilitate knowledge sharing and negotiation during early system design. Empirical observations show that when system-level requirements are not available or not mature enough, engineers dealing with the development of long lead-time sub-systems tend to target local optima, rather than opening up the design space. This phenomenon causes design teams to generate solutions that do not embody the best possible configuration for the overall system. The aim of this paper is to show how methodologies for value-driven design may address this issue, facilitating early stage design iterations and the resolution of early stage design trade-offs. The paper describes how such methodologies may help gathering and dispatching relevant knowledge about the ‘design intent’ of a system to the cross-functional engineering teams, so to facilitate a more concurrent process for requirement elicitation in SE. The paper also describes EVOKE (Early Value Oriented design exploration with KnowledgE maturity), a concept selection method that allows benchmarking design options at sub-system level on the base of value-related information communicated by the system integrators. The use of EVOKE is exemplified in an industrial case study related to the design of an aero-engine component. EVOKE’s ability to raise awareness on the value contribution of early stage design concepts in the SE process has been further verified with industrial practitioners in ad-hoc design episodes.     

基于信噪比的投资组合策略研究

采用收益率的协方差矩阵的特征根刻划投资的风险;用主成分综合反映证券市场的信息;用主成分的信噪比反映投资组合的期望收益率与风险之间的均衡关系,并以此作为投资组合收益极大化的指标;得到了不同与H.Markowitz的投资组合模型,并给出了具体的投资组合策略-卖空与非卖空条件下的投资组合的比例,文章最后给出了一个实例.     

Reconsideration on Homogeneous Quadratic Riemann Boundary Value Problem

The homogeneous quadratic Riemann boundary value problem (1) with Hoelder continuous coefficients for the normal case was considered by the author in 1997. But the solutions obtained there are incomplete. Here its general method of solution is obtained.     

美国USNews学科评估指标体系的剖析及其启示

通过学科评估指标体系的比较分析与研究,阐述了评估指标体系的客观性、可行性,分析了《美国新闻与世界报道》中多元学科评估指标体系的特点及对我国大学学科评估的启示。     

如何做好桩基工程旁站监理

文章介绍了桩基工程旁站监理的过程和实效及保证监理目标实现的具体措施。     

Abrupt climate change：Debate or action

Global abrupt climate changes have been documented by various climate records, including ice cores, ocean sediment cores, lake sediment cores, cave deposits, loess deposits and pollen records. The climate system prefers to be in one of two stable states, i.e. interstadial or stadial conditions, but not in between. The transition between two states has an abrupt character. Abrupt climate changes are, in general, synchronous in the northern hemisphere and tropical regions. The timescale for abrupt climate changes can be as short as a decade. As the impacts may be potentially serious, we need to take actions such as reducing CO2 emissions to the atmosphere.     

The Optimal Solution of the Model with Physical and Human Capital Adjustment Costs

We prove that the model with physical and human capital adjustment costs has optimal solution when the production function is increasing return and the structure of vetor fields of the model changes substantially when the prodution function from decreasing return turns to increasing return. And it is shown that the economy is improved when the coefficients of adjustment costs become small.     

基于B/S模式的水利水电工程造价管理系统研究

提出了基于B／S模式的水利水电工程造价管理系统，对B／S的体系结构、系统的总体结构设计、功能及功能设计进行了阐述，并说明了系统实现的关键技术．