Evaluation of Low-Grade Yellow-Poplar (Liriodendron tulipifera) as Raw Material for Cross-Laminated Timber Panel Production

Utilization of low-grade yellow-poplar (Liriodendron tulipifera) lumber would provide for alternative structural lumber sources and promote the growth of cross-laminated timber (CLT) manufacturing facilities within the Appalachian Region. A significant amount of low-grade yellow-poplar lumber (i.e., National Hardwood Lumber Association [NHLA] No. 2A and Below Grade) is utilized for wood pallets. In practice, this material is not graded for structural purposes. Additionally, research on yellow-poplar for structural use has focused on grading lumber from a small population of selected logs, not by regrading NHLA lumber from manufacturing facilities. Therefore, the research's objective was to investigate the structural grades of a typical population of NHLA graded No. 2 and lower lumber and evaluate their potential to meet structural grades necessary for CLT panels. NHLA graded lumber was regraded and assigned to visual structural grades following Northeastern Lumber Manufacturers Association rules and evaluated for flatwise bending modulus of elasticity (MOEb) by nondestructive proof loading. The results of the study indicated that 54.6 percent of the boards possessed a minimal structural visual grade required for CLT panels according to American National Standards Institutes/The Engineered Wood Association (ANSI/APA) PRG 320-2019 (2020). Splits were the most common limiting defect that downgraded boards to nonstructural grades. Also, 96.6 percent of the boards evaluated had a MOEb above the required minimal board value of 1.2 ×106 psi (8,274 MPa) listed in ANSI/APA PRG 320-2019 (2020). The results of the study indicated that a majority of NHLA low-grade yellow-poplar, when regraded for structural purposes, meets or exceeds minimum lumber grade values necessary for use in CLT panel production.

Prognostics and Secure Health Management (PSHM) of Electronic Systems in Zero-Trust Environment

The Prognostics and Health Management (PHM) of electronic systems has reached high levels of maturity, with both generic and system-specific PHM techniques available. While these techniques are able to detect naturally occurring faults and predict their impact on the system lifetime, they might not be able to do so if the faults are maliciously induced. Maliciously induced faults could be due to hardware threats; i.e., electronic products that are recycled, remarked, defective, cloned, or tampered (through the insertion of hardware trojans). Increased outsourcing in the fabrication of electronic products has made them susceptible to the insertion of hardware threats in untrusted manufacturing facilities. In many cases, hardware threats are more destructive than software ones as they cannot be remedied by a software patch and are difficult to remove. Hardware threats can cause undesired system behavior such as information leakage, functional failure, maliciously induced aging, etc. The proliferation of hardware threats could outpace the implementation of their detection mechanisms. This might lead to a scenario where all products manufactured by untrusted manufacturing facilities are suspect until verified otherwise. This has parallels to Zero-Trust Architecture, a network security concept developed to help prevent data breaches by removing the notion of trust from an organization's network architecture. To extend the concept of Zero-Trust Architecture from the network to the hardware domain and to ensure hardware security, a paradigm shift from PHM to PSHM (Prognostics and Secure Health Management) is needed. This paper lays out a compelling case for the need for this shift and how the PHM community can adapt its research to ensure the safe, reliable, and secure operation of systems in this challenging new environment.

China’s Mega Supply Chains

This chapter explains the development and significance of China’s mega supply chains and their position in the global division of labour. It explains the importance of modularity, standardization, and complementarity in supply chains. It analyses how efficiencies and resilience are achieved and balanced in supply chains and the importance of platforms, both geographical clusters, such as industrial bases in Shenzhen, Chengdu, and Suzhou, and digital platforms, such as Alibaba and Pinduoduo. The chapter also argues that China’s mega supply chains have become regional hubs supplying intermediate products to manufacturing facilities in countries with lower labour costs. It discusses the extent to which China is progressing towards Industry 4.0, with smart supply chains, and how the country is responding to the challenges from growing global trade tensions.

Does Water Scarcity Affect Environmental Performance? Evidence from Manufacturing Facilities in Texas

It is well known that manufacturing operations can affect the environment, but hardly any research explores whether the natural environment shapes manufacturing operations. Specifically, we investigate whether water scarcity, which results from environmental conditions, influences manufacturing firms to lower their toxic releases to the environment. We created a data set that spans 2000–2016 and includes details on the toxic emissions of 3,092 manufacturing facilities in Texas. Additionally, our data set includes measures of the water scarcity experienced by these facilities. Our econometric analysis shows that manufacturing facilities reduce their toxic releases into the environment when they have experienced drought conditions in the previous year. We examine facilities that release toxics to water as well as facilities with no toxic releases to water. We find that the reduction in total releases (to all media) is driven mainly by those facilities that release toxic chemicals to water. Further investigation at a more granular level indicates that water scarcity compels manufacturing facilities to lower their toxic releases into media other than water (i.e., land or air). The impact of water scarcity on toxic releases to water is more nuanced. A full-sample analysis fails to link water scarcity to lower toxic releases to water, but a further breakdown shows that manufacturing facilities in counties with a higher incidence of drought do lower their toxic releases to water. We also find that facilities that release toxics to water undertake more technical and input modifications to their manufacturing processes when they face water scarcity. This paper was accepted by David Simchi-Levi, operations management.

Architectural Environmental, And Process Flow in Constructing Modern Factories for Manufacturing Eco-Friendly Furniture

Today, a dominant trend in factory construction is to account for the eco-economic aspects of their further operations. It requires sustainable technological solutions, with regard for structural specificities or for production technology used. At the same time, the buildings shall be architecturally attractive and distinct. In the paper, the author considered architectural, technological, structural, ecological, and economic factors for construction of wood-processing and furniture-making facilities. The author analyzed the actual Project Design to build the type of facility in Krekhiv village, Zhovkva district, Lviv region (western Ukraine) as commissioned by a well-known French company (the author have been engaged in the design). The study focused on a wood-processing Woodman company designed for the midtech production of edge glued panels and furniture. According to the design documentation by types of products planned, the Project Design provided for the following production units: unit for wood-sawing and drying; unit for mechanical processing of wood, production of edge glued panels and furniture; unit for mechanical repairs; and an administrative and services unit. The anticipated annual production capacity is: for edge glued panels – 600 m3 a year, furniture production– up to 4,000 pc a year. “Wood-sawing unit”, according to the Project Design, is organized according to the following principles of production technology based on the stages and operations: stockholding and storage of round timber (sawtimber); cutting the sawtimber into the shaped timber and logs; stocking the sawn timber (untrimmed boards) into stockpiles and on separators for further atmospheric and chamber drying. Sawn timber drying is taking place in the “Drying Unit”. It is the process of moisture removal from timber to a certain degree of humidity. The Project Design provided for the atmospheric drying of logs and boards in the furnished stockpiles under the roof, and artificial seasoning in a steam-curing and drying chambers. The artificial seasoning technology for sawn timber and logs is organized with the help of drying chambers and a boiler room with a sawdust bunker. The “Unit for Mechanical Wood Processing, Production of Edged Glued Panels and Furniture” is used for production of the edged glued panels from the sawn timber coming from hardwood (beech, oak). The production process of the edged glued panels includes the following stages: 1) cross-cutting of dry boards; 2) line cutting of board edges for the rough-sawn stock; 3) primary mechanical processing; 4) sorting by quality, color; 5) end-jointing gluing line; 6) log finishing; 7) press-molding of logs into panels; 8) panel surface preparation; 9) size cutting; 10) preservative treatment; 11) quality control; 12) storage and sales. "Administrative and Service Block", according to the Project Design, is an inbuilt part of the Main Building (Unit). It is a two-story insert separated with the fire safety barriers from the manufacturing facilities. It has isolated outside entrances and a technological corridor linking the manufacturing facilities. With account for production process requirements, fire safety, and sanitary standards, the Unit is divided into several personal services rooms for the staff and administrative rooms.