Machine Learning in Chemical Engineering: Strengths,Weaknesses, Opportunities,and Threats

Chemical engineers rely on models for design, research, and daily decision-making, often with potentially large financial and safety implications. Previous efforts a few decades ago to combine artificial intelligence and chemical engineering for modeling were unable to fulfill the expectations. In the last five years, the increasing availability of data and computational resources has led to a resurgence in machine learning-based research. Many recent efforts have facilitated the roll-out of machine learning techniques in the research field by developing large databases, benchmarks, and representations for chemical applications and new machine learning frameworks. Machine learning has significant advantages over traditional modeling techniques, including flexibility, accuracy, and execution speed. These strengths also come with weaknesses, such as the lack of interpretability of these black-box models. The greatest opportunities involve using machine learning in time-limited applications such as real-time optimization and planning that require high accuracy and that can build on models with a self-learning ability to recognize patterns, learn from data, and become more intelligent over time. The greatest threat in artificial intelligence research today is inappropriate use because most chemical engineers have had limited training in computer science and data analysis. Nevertheless, machine learning will definitely become a trustworthy element in the modeling toolbox of chemical engineers.     

Teams that Work: Campus Culture,Engineer Identity,and Social Interactions

Not all student teams are created equal. Some manage to produce excellent engineering results, others fabricate it. Social interactions in some teams are respectful, while on other teams some members expect others to carry the load, but take credit for it later. With engineering teamwork becoming more prevalent on engineering campuses, knowing more about student design teams that work is especially important. This article uses two teamwork cases from a large‐scale ethnographic study of an engineering design program to describe not only the ways that student engineers practiced design teamwork, but also how campus culture reached into social interactions between teammates via engineering identities produced on campus. A model for effective teamwork emerged that implies producing high quality engineering products, and doing so through respectful social interactions. Implications for teaching about teamwork, teaching with teams, and thinking about ways to change campus cultures to better promote design engineering are developed.     

工程 工程系统 工程系统论与工程科学体系

从分析工程的基本内容、性质和特征人手,引出了工程系统的概念,接着应用一般系统论思想讨论了工程系统论的研究对象和研究方法,并论述了它在整个工程科学体系中的元学科地位。     

The influence of approaches for the purification of natural cancellous bone grafts: Morphology, microstructure, composition, strength and biocompatibility study

To find an optimal approach for preparation of porous scaffold for tissue engineering, natural cancellous bone were processed with several techniques: calcination, lyophilization, treatment of chemical reagents and supercritical CO₂ fluid extraction, respectively. Scanning electron micrograph, energy dispersive X-ray microanalysis, X-ray diffraction, Micro-CT, mechanical test and T-cell proliferation assay were used to observe and compare morphology, microstructure, composition, mechanical strength and biocompatibility of the different scaffolds. After processing all the scaffolds exhibited natural porous three-dimension microstructure, and the composition and properties of natural bone, such as Ca/P ratio and hydroxyapatite crystal were still preserved in all of them. Except scaffolds processed with lyophilization, all the other scaffolds showed no influence on the proliferation of T-cell. And scaffolds processed with supercritical CO₂ fluid performed higher compressive strength than that of the other scaffolds, which was similar to natural bones. As the consequence, supercritical CO₂ fluid extraction may be a useful approach for preparation of natural scaffolds for tissue engineering.     

Estimating professional service productivity: theoretical model,empirical estimates and external validity

Productivity of professional service is difficult to measure, due to the high degree of customization, variable throughput time, and high degree of labor intensity. Using the complex design engineering for large construction projects as an example, this study reviews the common professional service productivity measurement problem of determining surrogate measures of inputs and outputs. This research was sponsored by the construction industry, and required a team of academic and construction executives to work closely to develop a procedure and a comprehensive empirical model for measuring engineering design productivity. The model addresses the complexity of productivity estimation arising from the interactions among the multiple outputs and variability of labor hours, both requiring surrogate measures. The mathematical model was statistically estimated using data from a large number of design engineering organizations. The statistical results and the model were externally validated in several organizations for their pragmatic usefulness. The proposed methodology is applicable to those service industries where there are high degrees of output variability and highly skilled professionals working to achieve complex objectives.     

海洋工程装备建造设备发展浅探

海洋工程装备向大型化、深水化发展,性能要求不断提高。海洋装备的建造面临着制造难度提升、环境更为复杂、关键设备精度要求高等难题,对创新加工装备、加工模式等提出了更高要求。制造设备需要在精细化、柔性化、加工与测量相结合等方面提升加工能力,同时在加工设备成套组织、加工控制软件等领域取得突破,从而为海洋工程装备产业的发展提供建造能力的支持,实现制造过程的精细化、智能化和绿色化发展。     

美国加州大学圣迭哥分校工程图学课程教学研究

介绍了美国加州大学圣迭哥分校工程图学与设计入门课程的教学内容和教学特点,总结了其在授课师资、助教配置、实验室管理、课程网站建设、成绩评定、教学评价与反馈等环节的具体作法.详细分析了课程教学中对学生多种素质和能力的培养,特别是对学生动手能力、创新能力、学术诚信素质和团队合作素质的培养.探讨了对国内工程图学教学改革的启示和借鉴.     

Alternative tissue engineering scaffolds based on starch: processing methodologies, morphology, degradation and mechanical properties

An ideal tissue engineering scaffold must be designed from a polymer with an adequate degradation rate. The processing technique must allow for the preparation of 3-D scaffolds with controlled porosity and adequate pore sizes, as well as tissue matching mechanical properties and an appropriate biological response.

This communication revises recent work that has been developed in our laboratories with the aim of producing 3-D polymeric structures (from starch-based blends) with adequate properties to be used as scaffolds for bone tissue engineering applications. Several processing methodologies were originally developed and optimised. Some of these methodologies were based on conventional melt-based processing routes, such as extrusion using blowing agents (BA) and compression moulding (combined with particulate leaching). Other developed technologies included solvent casting and particle leaching and an innovative in situ polymerization method.

By means of using the described methodologies, it is possible to tailor the properties of the different scaffolds, namely their degradation, morphology and mechanical properties, for several applications in tissue engineering. Furthermore, the processing methodologies (including the blowing agents used in the melt-based technologies) described above do not affect the biocompatible behaviour of starch-based polymers. Therefore, scaffolds obtained from these materials by means of using one of the described methodologies may constitute an important alternative to the materials currently used in tissue engineering.     

Assessment in Engineering Education: Evolution,Approaches and Future Collaborations

This article examines the current state of assessment in engineering education in the United States as reflected in the Journal of Engineering Education. We begin with a brief review of recent developments in the assessment of engineering education and the events that have inspired change. Next, we explore assessment methodologies that have been used repeatedly in the evaluation of engineering courses, curricula, and research investigations as well as some methods that have not been used extensively but are likely to be informative. We conclude with a discussion of the importance of establishing collaborations between researchers in engineering education and educational research. Throughout this paper we highlight examples of sound and rigorous assessments in engineering education.     

Cloaked Exosomes: Biocompatible,Durable, and Degradable Encapsulation

Exosomes—nanosized extracellular vesicles (EVs) naturally secreted from cells—have emerged as promising biomarkers and potential therapeutic vehicles, but methods to manipulate them for engineering purposes remain elusive. Among the technical obstacles are the small size and surface complexity of exosomes and the complex processing steps required, which reduce the biocompatibility of currently available methods. The encapsulation of exosomes with a nanofilm of supramolecular complexes of ferric ions (Fe³⁺) and tannic acid is demonstrated here. The resulting natural polyphenol, ≈10 nm thick, protects exosomes from external aggressors such as UV‐C irradiation or heat and is controllably degraded on demand. Furthermore, gold nanoparticles can be covalently attached for single‐exosome level visualization. To fully exploit their therapeutic potential, chemotherapeutic drug‐loaded EVs are functionalized to achieve the targeted, selective killing of cancer cells preferentially over normal cells. This nanofilm not only preserves the native size and chemical makeup of the intrinsic exosomes, but also confers new capabilities for efficient tumor targeting and pH‐controlled release of drugs. Demonstrating a scalable method to produce biocompatible, durable, on‐demand degradable, and chemically controllable shields for exosome modification and functionalization, the methods introduced here are expected to bring the potential of exosome‐based nanomedicine applications closer to reality.     

军事工程物联网：概念模型、支撑技术与领域应用

本文将物联网的思想和技术引入军事工程领域,提出军事工程物联网的研究理念,以促进军事工程与高度信息化的指挥系统和武器平台的对接和融合;定义了军事工程物联网的基本概念,分析了其内涵,建立了军事工程物联网的概念模型;结合军事工程物联网研究所面临的技术挑战,阐述了笔者在军事工程感知技术、军事工程特殊空间的网络传输技术、军事工程多模式大数据资源管理与挖掘技术、面向军事工程物联网的软件范型等方面的研究进展和成果;最后讨论了军事工程物联网在军港工程岸基保障中的应用实例。军事工程物联网对于有效提升军事工程的综合保障能力和防护能力具有重要意义。     

Getting the Numbers Right: International Engineering Education in the United States,China, and India

This article challenges the commonly cited statistics for engineering graduates in the United States, China, and India. Our research shows that the gap between the number of engineers and related technology specialists produced in the United States versus those in India and China is smaller than previously reported, and the United States remains a leading source of high‐quality global engineering talent. Furthermore, engineering graduates in China and India face the prospect of substantial unemployment, despite high corporate demand for their services; this raises questions about the quality of recent graduates. The United States, however, also confronts problems in its continued ability to attract and retain top engineering talent from abroad because of visa uncertainties and growing economic opportunities in their countries of origin. We argue that the key issue in engineering education should be the quality of graduates, not just the quantity, since quality factors have the biggest impact on innovation and entrepreneurship.     

Tissue engineering of replacement skin: the crossroads of biomaterials, wound healing, embryonic development, stem cells and regeneration

Advanced therapies combating acute and chronic skin wounds are likely to be brought about using our knowledge of regenerative medicine coupled with appropriately tissue-engineered skin substitutes. At the present time, there are no models of an artificial skin that completely replicate normal uninjured skin. Natural biopolymers such as collagen and fibronectin have been investigated as potential sources of biomaterial to which cells can attach. The first generation of degradable polymers used in tissue engineering were adapted from other surgical uses and have drawbacks in terms of mechanical and degradation properties. This has led to the development of synthetic degradable gels primarily as a way to deliver cells and/or molecules in situ, the so-called smart matrix technology. Tissue or organ repair is usually accompanied by fibrotic reactions that result in the production of a scar. Certain mammalian tissues, however, have a capacity for complete regeneration without scarring; good examples include embryonic or foetal skin and the ear of the MRL/MpJ mouse. Investigations of these model systems reveal that in order to achieve such complete regeneration, the inflammatory response is altered such that the extent of fibrosis and scarring is diminished. From studies on the limited examples of mammalian regeneration, it may also be possible to exploit such models to further clarify the regenerative process. The challenge is to identify the factors and cytokines expressed during regeneration and incorporate them to create a smart matrix for use in a skin equivalent. Recent advances in the use of DNA microarray and proteomic technology are likely to aid the identification of such molecules. This, coupled with recent advances in non-viral gene delivery and stem cell technologies, may also contribute to novel approaches that would generate a skin replacement whose materials technology was based not only upon intelligent design, but also upon the molecules involved in the process of regeneration.