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The shipping industry has faced two major challenges during 2019-2022: the implementation of International Maritime Organization (IMO) norms on the maximum allowed sulfur concentration to be 0.5% in marine fuel, which also are known as IMO 2020 norms, from Jan 1, 2020, and the COVID-19 pandemic, which disrupted normal operations. The next challenges that the shipping industry is expected to face are the decarbonization 2030 and 2050 norms. This article will focus on the aftermaths of the IMO 2020 norms and the COVID-19 pandemic on the marine lubricants industry and how it is likely to evolve in the future as the shipping industry tries to meet the decarbonization targets.
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With the gradual normalization of the COVID-19, unmanned delivery has gradually become an important contactless distribution method around China. In this paper, we study the routing problem of unmanned vehicles considering path flexibility and the number of traffic lights in the road network to reduce the complexity of road conditions faced by unmanned vehicles as much as possible. We use Monte Carlo Tree Search algorithm to improve the Genetic Algorithm to solve this problem, first use Monte Carlo Tree Search Algorithm to compute the time-saving path between two nodes among multiple feasible paths and then transfer the paths results to Genetic Algorithm to obtain the final sequence of the unmanned vehicles fleet. And the hybrid algorithm was tested on the actual road network data around four hospitals in Beijing. The results showed that compared with normal vehicle routing problem, considering path flexibility can save the delivery time, the more complex the road network composition, the better results could be obtained by the algorithm.
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Purpose>The purpose of this study is to identify, analyse and model the post-processing barriers of 3D-printed medical models (3DPMM) printed by fused deposition modelling to overcome these barriers for improved operational efficiency in the Indian context.Design/methodology/approach>The methodology used interpretive structural modelling (ISM), cross-impact matrix multiplication applied to classification (MICMAC) analysis and decision-making trial and evaluation laboratory (DEMATEL) to understand the hierarchical and contextual relations among the barriers of the post-processing.Findings>A total of 11 post-processing barriers were identified in this study using ISM, literature review and experts' input. The MICMAC analysis identified support material removal, surface finishing, cleaning, inspection and issues with quality consistency as significant driving barriers for post-processing. MICMAC also identified linkage barriers as well as dependent barriers. The ISM digraph model was developed using a final reachability matrix, which would help practitioners specifically tackle post-processing barriers. Further, the DEMATEL method allows practitioners to emphasize the causal effects of post-processing barriers and guides them in overcoming these barriers.Research limitations/implications>There may have been a few post-processing barriers that were overlooked by the Indian experts, which might have been important for other country's perspective.Practical implications>The presented ISM model and DEMATEL provide directions for operation managers in planning operational strategies for overcoming post-processing issues in the medical 3D-printing industry. Also, managers may formulate operational strategies based on the driving and dependence power of post-processing barriers as well as the causal effects relationships of the barriers.Originality/value>This study contributes to identifying, analyzing and modelling the post-processing barriers of 3DPMM through a combined ISM and DEMATEL methodology, which has not yet been reviewed. This study also contributes to decision makers developing suitable strategies to overcome the post-processing barriers for improved operational efficiency.
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In October, the White House convened an indoor air quality summit of government agencies and experts from public and private organizations to discuss public policy that could be adopted in response to lessons learned from the COVID-19 pandemic.1
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Because of the impact that COVID-19 is having on conferences, please check the conference's website for the most up-to-date information. 2023 JANUARY ABMA Annual Meeting, Jan. 13 - 16, Carlsbad, Calif. Contact the Indoor Air Quality Association at 844-802-4103, info@iaqa.org or https://annualmeeting.iaqa.org MARCH HVAC Cold Climate Conference 2023, March 6 - 8, Anchorage, Alaska. Contact the American Council for an Energy-Efficient Economy at 202-507-4000 or www.aceee.org/2023-hot-water-forum IIAR Natural Refrigeration Conference & Heavy Equipment Expo, March 12 - 15, Long Beach, Calif.
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The North American International Auto Show (NAIAS) returned to Detroit in September after a three-year hiatus due to the COVID-19 pandemic, and it could fairly be described as weird. Becker usually attends to see not just the latest automobile designs but the newest technology. This year, the show was smaller than ever, had fewer automakers participating and had almost no displays on the inner workings of the vehicles. How did the public react? One measure would be attendance, which in prepandemic years often exceeded 800,000 people. Unfortunately, the Detroit Auto Dealers Association (DADA), which runs the show, has announced it will not be releasing attendance figures this year. A DADA spokesperson, Frank Buscemi, didn't explain the reason behind this decision. His guess is that the number would be embarrassingly small.
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Droplet impact on a flexible substrate is a prevalent phenomenon in nature and various advanced technologies such as soft bio-printing, tissue engineering, smart biomaterials and flexible electronics. Recent rapid advancement in new functional surfaces, ultra-high-speed imaging, nanotechnology, deep learning, advanced computational strength and the relation between fluid dynamics and interfacial science have intensified the physical understanding of droplet impact on soft materials. Once a droplets impacts on a solid surface, it deposits, spreads, rebounds or splashes. Given the importance of the droplet impact onto soft substrates in biotechnology, medicine and advanced flexible electronics, a deep physical understanding of such complex phenomenon is vital. This review initially presents the liquid-solid interaction physics and relevant interfacial science. Next, this review discusses the physics of droplet impact on soft materials with different physical and interfacial characteristics. Moreover, this review presents advancements in droplet impact on elastic materials relevant to new technologies such as soft electronics, elastic smart biomaterials, tissue engineering and the fight against COVID-19 pandemic. Finally, this review lays out future research directions related to current problems in such complex physical phenomenon.
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Computational fluid dynamics (CFD) models of an aircraft cabin and an indoor commercial space (ICS) were used to characterize the spread of aerosols generated by a coughing or breathing person suffering from a respiratory illness. Occupant exposure to these aerosols was then compared between the ICS and the aircraftcabin. The lifetime of the aerosols, system designs and airflow patterns that reduce their concentration over time were also examined. Differences between steady state and well-mixed conditions were identified and comparisons made between the model environments. The CFD analysis results were also compared to empirical data from a U.S. Transportation Command study that tracked particles introduced by simulated infectious individuals in an airplane cabin environment.
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Researching and testing water to protect fish might seem obvious. Surprisingly, a parallel approach of analyzing and managing the predominant human exposure--indoor air--to optimize occupant well-being and productivity is not a priority for building management. We are indoors approximately 90% of the time, and health is people's most valuable asset, yet there is a lack of data relating indoor air quality (IAQ) to health outcomes. The most understandable obstacle is that relating IAQ to health outcomes is complex. The very fact that humans are resilient and able to withstand mild physiological stress without immediately obvious consequences makes correlating indoor exposures with health changes a difficult task. Despite these challenges, they need to pay attention to what IAQ data would tell. In fact, paying attention is not enough. They need to agree on what levels are good or bad and manage IAQ accordingly.
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Most of us had unique work experiences during the heart of the pandemic. This might include layoffs, furloughs, sabbaticals, job changes, new responsibilities, work from home, restricted travel, virtual company meetings and job interviews, virtual customer visits, stringent safety protocols, new learning, upskilling and personal achievements that helped your employer stay profitable (or afloat). If you have not done so already, it is time to think about and document your proudest accomplishments during the pandemic, including how your experience can benefit an employer in the post-pandemic job environment. Much of this experience can be included in either your resume or cover letter (or both). When you describe your pandemic-era accomplishments in your resume, display your adaptability, creativity and leadership skills to employers. Here, Pelczarski looks at what types of special, unique and/or unusual experience and accomplishments from the pandemic job environment can be included in your resume and cover letter.
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In a speech, ASHRAE president Farooq Mehboob discusses various issues including the importance of forming relationships, gaining knowledge and embracing change. He also highlights the hostilities that led to the breakup of Pakistan into two countries: East Pakistan became Bangladesh, and West Pakistan became modern-day Pakistan.
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The COVID-19 pandemic has driven public interest in building ventilation rates. The ASHRAE Epidemic Task Force's recommendation that buildings "provide and maintain at least the minimum outdoor airflow rates for ventilation as specified by applicable codes and standards" put quantitative ventilation system assessments in high demand. Throughout the pandemic, many building owners conducted assessments of building systems, including ventilation, to reduce risk of COVID-19 transmission. A recent study of assessments at 95 commercial office buildings found that 77% provided minimum ventilation rates or could make minor adjustments to do so. However, 23% of buildings were underventilated and would require significant capital investment to meet current standards. All but one of these buildings were designed between 1981 and 1992, with ventilation rates as low as 9 cfm/person (4 L/s person) (assuming default occupant density).
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Another continuous maintenance cycle for ANSI/ASHRAE Standard 62.1 has concluded, and the keen observer will have already noticed one of the changes made in the 2022 edition of the standard. Despite the conditions created by the COVID-19 pandemic, the committee has continued to meet over the past two years, more often in web conferences than in person, to consider continuous maintenance proposals and interpretation requests and to discuss issues related to ventilation and indoor air quality. The addenda that have been adopted to the 2019 edition of that standard generally fall into three categories: clarifications, harmonization and improved procedures. Work was also begun on mandatory air density corrections, further development of humidity control requirements and addressing future extreme events, but this work was not completed in time for inclusion in the 2022 edition of the standard.
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Robert Guery, Life MemberASHRAE, Ebmatingen, Switzerland * From July's "Confessions of a Control Freak," by Andy Pearson, Ph.D., C.Eng., Fellow ASHRAE, regarding cooling systems with multiple capacity stages that "hunt," in addition to increasing the stage delay time, one should also consider the cooling demand side. MemberASHRAE, Brisbane, Australia Airborne Disease Transmission Risk We read "Airborne Disease Transmission Risk and Energy Impact of HVAC Mitigation Strategies" by Michael J. Risbeck, Ph.D., et al., from May with great interest, and we agree that ventilation is a costly source of achieving adequate equivalent outdoor air (EOA) supply. [...]the cost of operating ventilation systems for reducing infection risk is much lower than the cost of taking care of a large number of infected patients.1 Overloading the health-care system is a painful lesson learned in many places.
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Because of the impact that COVID-19 is having on conferences, please check the conference's website for the most up-to-date information. DECEMBER HARDI Annual Conference, Dec, 3-6, Houston, Contact Heating Air-conditioning & Refrigeration Distributors International at 888-253-2128, hardimail@hardinet.org or https://hardinet.org/events Buildings XV Conference, Dec, 5-8, Clearwater Beach, Fla, Contact ASHRAE at 800-527-4723, meetings@ashrae.org or www.ashrae.org/buildingsxv International Conference on Building Ventilation and Air Conditioning, Dec. 9-10, New York, N.Y. Contact organizers at https://tinyurl.com/ICBVAC22 2023 JANUARY ABMA Annual Meeting, Jan. 13-16, Carlsbad, Calif. Contact the American Council for an Energy-Efficient Economy at 202-507-4000 or www.aceee.org/2023-hot-water-forum IIAR Natural Refrigeration Conference & Heavy Equipment Expo, March 12-15, Long Beach, Calif.
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New research from the McKinsey & Co consulting firm confirms what many of us have sensed in the COVID-19 era--the health of our professional networks has been adversely affected by the pandemic. That's not good news for individual professionals or their companies and organizations. The study, which questioned about 5,500 US workers on their networks and connections, found more than three-quarters of the respondents said that they "are connecting with others less frequently, have smaller networks and spend less time and effort on relationship building since the start of the pandemic." The STLE can play a role in helping people in the tribology and lubricants business to repair lost connections and acquire some new ones. Here, Salek presents some practical ideas on how to do that.
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Significant emphasis has been placed on enhancing building HVAC systems to be more energy-efficient in recent decades. Often, these measures include reducing ventilation rates and overall airflows to achieve corresponding energy reduction. However, the COVID-19 pandemic caused an examination of how HVAC systems may help reduce the risk of airborne transmission of respiratory diseases via infectious aerosols. This new goal of infection risk mitigation often leads to the opposite recommendation-that outdoor air ventilation be increased,1 to the detriment of energy efficiency.2,3
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Models were run to reproduce COVID-19 infections versus deaths in Mexico City. The first model was made using rain runoff concept, emulating rain as number of infections reproducing runoff as number of deaths given as of March 2020. The second consisted of using an artificial neural network (ANN) proposed as an initial condition function to be implemented in the model with delay. These models were applied to fit accumulated confirmed case data, obtaining fit corroborated by coefficient of determination, R2. The R2 value produced by model was 0.0528 in case of infections comparison vs. official deaths reported by the Ministry of Health, 0.0571 for t case of infections vs. modelling using the HEC-HMS tool, and 0.0937 for case of contagion vs. modelling using ANN.
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Natural gas is acting as a transitional fuel source as the world shifts toward fully renewable energy. Recently, Europe has confirmed this continued usage of natural gas, with the European Union voting in favor of calling natural gas a "green" or "sustainable" source of energy despite some pushback. However, there is one caveat: a further transition toward biogas or green hydrogen and other renewable gases by 2035. This is a good sign that natural gas power generation units will have a solid future in the energy mix of tomorrow.