Design and Evaluation of a Marine Scrubber System

Increasingly stringent oxides of nitrogen (NOX) emissions regulations for diesel marine engines are resulting in the development of newer engines with inherent NOX emissions reduction technologies. With typical useful service lives over 20 years, older diesel marine engines are producing disproportionate amounts of NOX emissions when compared with their newer counterparts. The development of retrofit exhaust aftertreatment technologies would therefore aid in reducing the total NOX emissions from these engines.;A marine scrubber system for the reduction of NOX emissions from diesel marine engines was designed, constructed, and evaluated. This work focused on gathering data for the design of a marine scrubber system specifically for use with marine harbor craft. The operation of the marine scrubber system was based on and designed using NOX absorption theory. The system consisted of a continuously regenerating diesel particulate filter and diesel oxidation catalyst for oxidation of nitric oxide to nitrogen dioxide, a heat exchanger for exhaust gas temperature reduction, a scrubber unit for NOX gas absorption, and a liquor pump for liquor recirculation.;The system was tested with a 1992 Mack E7 engine over two test cycles, a High Flow cycle and Low Flow cycle. The High Flow cycle was used to represent marine harbor craft operation. Over this cycle the system was able to reduce engine NOX emissions by an average of 41.2%. The Low Flow cycle was developed to investigate the operating parameters of the scrubber unit. Over the Low Flow cycle the system was able to reduce engine NOX emissions by an average of 59.9%. The collection of data from this system facilitated parameter estimation and therefore future optimization of marine scrubber system design and control decisions

Mechanical performance of composite bonded joints in the presence of localised process-induced zero-thickness defects

Processing parameters and environmental conditions can introduce variation into the performance of adhesively bonded joints. The effect of such variation on the mechanical performance of the joints is not well understood. Moreover, there is no validated nondestructive inspection (NDI) available to ensure bond integrity post-process and in-service so as to guarantee initial and continued airworthiness in aerospace sector. This research studies polymer bond defects produced in the laboratory scale single-lap composite-to-composite joints that may represent the process-induced defects occurring in actual processing scenarios such as composite joining and repair in composite aircrafts. The effect of such defects on the degradation of a joint's mechanical performance is then investigated via quasi-static testing in conjunction with NDI ultrasonic C-scanning and pulsed thermography. This research is divided into three main sections: 1- manufacturing carbon fibre-reinforced composite joints containing representative nearly zero-thickness bond defects, 2- mechanical testing of the composite joints, and 3- assessment of the NDI capability for detection of the bond defects in such joints

A finite element study of fatigue crack propagation in single lap bonded joint with process-induced disbond

This paper presents a method for predicting fatigue crack propagation in adhesive bonded composite joints with an initial full-width disbond using finite element analysis and numerical integration of the material's fatigue crack growth rate law. Fatigue tests were conducted on single lap joints. Crack lengths were monitored from four runout corners. In-situ crack growth measurements were performed by ink injection to identify the crack front profile during fatigue loading. The crack growth was modelled using a fracture mechanics criterion considering two different crack propagation patterns. The material's fatigue crack growth rate law was determined experimentally using the standard double cantilever beam and end notch flexure specimens. Using the total strain energy release rate and the two crack scenarios, the numerical model predicted the lower and upper bounds of the measured fatigue crack growth rates of the lap joint

Factors for Supporting Primary Care Physician Engagement With Patient Apps for Type 2 Diabetes Self-Management That Link to Primary Care: Interview Study.

BACKGROUND: The health burden of type 2 diabetes can be mitigated by engaging patients in two key aspects of diabetes care: self-management and regular contact with health professionals. There is a clear benefit to integrating these aspects of care into a single clinical tool, and as mobile phone ownership increases, apps become a more feasible platform. However, the effectiveness of online health interventions is contingent on uptake by health care providers, which is typically low. There has been little research that focuses specifically on barriers and facilitators to health care provider uptake for interventions that link self-management apps to the user's primary care physician (PCP). OBJECTIVE: This study aimed to explore PCP perspectives on proposed features for a self-management app for patients with diabetes that would link to primary care services. METHODS: Researchers conducted 25 semistructured interviews. The interviewer discussed potential features that would link in with the patient's primary care services. Interviews were audio-recorded, transcribed, and coded. Framework analysis and the Consolidated Criteria for Reporting Qualitative Research checklist were employed to ensure rigor. RESULTS: Our analysis indicated that PCP attitudes toward proposed features for an app were underpinned by perceived roles of (1) diabetes self-management, (2) face-to-face care, and (3) the anticipated burden of new technologies on their practice. Theme 1 explored PCP perceptions about how an app could foster patient independence for self-management behaviors but could also increase responsibility and liability for the PCP. Theme 2 identified beliefs underpinning a commonly expressed preference for face-to-face care. PCPs perceived information was more motivating, better understood, and presented with greater empathy when delivered face to face rather than online. Theme 3 described how most PCPs anticipated an initial increase in workload while they learned to use a new clinical tool. Some PCPs accepted this burden on the basis that the change was inevitable as health care became more integrated. Others reported potential benefits were outweighed by effort to implement an app. This study also identified how app features can be positively framed, highlighting potential benefits for PCPs to maximize PCP engagement, buy-in, and uptake. For example, PCPs were more positive when they perceived that an app could facilitate communication and motivation between consultations, focus on building capacity for patient independence, and reinforce rather than replace in-person care. They were also more positive about app features that were automated, integrated with existing software, flexible for different patients, and included secondary benefits such as improved documentation. CONCLUSIONS: This study provided insight into PCP perspectives on a diabetes app integrated with primary care services. This was observed as more than a technological change; PCPs were concerned about changes in workload, their role in self-management, and the nature of consultations. Our research highlighted potential facilitators and barriers to engaging PCPs in the implementation process

The use of history to identify anterior cruciate ligament injuries in the acute trauma setting: the 'LIMP index'

YesObjective To identify the injury history features reported by patients with ACL injuries and determine whether history may be used to identify patients requiring follow-up appointments from acute trauma services. Multi-site cross-sectional service evaluation using a survey questionnaire design conducted in the UK. The four injury history features investigated (LIMP) were ‘Leg giving way at the time of injury’, ‘Inability to continue activity immediately following injury’, ‘Marked effusion’ and ‘Pop (heard or felt) at the time of injury’. 194 patients with ACL injury were identified of which 165 (85.5%) attended an acute trauma service. Data on delay was available for 163 (98.8%) of these patients of which 120 (73.6%) had a follow-up appointment arranged. Patients who had a follow-up appointment arranged waited significantly less time for a correct diagnosis (geometric mean 29 vs 198 days; p<0.001) and to see a specialist consultant (geometric mean 61 vs 328 days; p<0.001). Using a referral threshold of any 2 of the 4 LIMP injury history features investigated, 95.8% of patients would have had a follow-up appointment arranged. Findings support the value of questioning patients on specific injury history features in identifying patients who may have suffered ACL injury. Using a threshold of 2 or more of the 4 LIMP history features investigated would have reduced the percentage of patients inappropriately discharged by 22.2%. Evidence presented suggests that this would significantly reduce the time to diagnosis and specialist consultation minimising the chance of secondary complications

Optimizing the mechanical properties of cement composite boards reinforced with cellulose pulp and bamboo fibers for building applications in low-cost housing estates

Africa is the third-richest continent in the world in terms of bamboo species. Despite these laudable natural resources, most African countries still use asbestos cement board as one of their major building materials. This is chiefly due to the high cost of equipment and technologies associated with non-asbestos-fiber cement board production. The current research seeks to underscore the possibility of utilizing these massive continent resources for non-asbestos-fiber cement board production by employing the existing production process in the asbestos cement industries via an innovatively developed laboratory-simulated Hatschek process. Non-asbestos-fiber cement boards incorporating kraft and bamboo fibers were successfully produced in the laboratory using this innovative method based on Hatschek technology, with natural fibre addition in the range of 2–6 wt.%. Experimental results revealed that the Flexural strength and deflection of the board improved significantly, producing optimum values of 10.41 MPa and 2.0 mm, respectively for composite board reinforced with 10 wt.% and 6 wt.% of kraft pulp and bamboo fibers, respectively. The SEM morphology of the fractured surfaces revealed the mode of composite fracture as well as good interaction at the fiber–matrix interface. Overall, the mechanical properties of the developed composite boards satisfy the minimum requirements of relevant standards based on fiber cement flat sheets and can be employed for internal building applications in low-cost housing estates in developing countries. The outcome of this research indicates that the current industrial production process based on Hatschek technology can be employed for non-asbestos-fiber cement board production using the studied natural fiber.This research was funded by the Tertiary Education Trust Fund (TETFund), Nigeria, through the Academic Staff Training and Development (AST&D) scholarship grant number TETF/ES/ UNIV/ONDO STATE/TSAS/2019/Vol.1

Learners' experience and perceived impact of a health literacy program in adult basic education: a qualitative study.

Objectives and importance of the study: Adult literacy programs aim to empower learners to participate more effectively in everyday life. This includes programs with health content embedded in curricula to target health literacy. Adult learners who attend these programs represent a heterogeneous population, but include a high proportion of hard-to-reach or socially disadvantaged groups in terms of age, ethnicity, educational background, language and prevalence of learning disabilities. In 2014, we conducted a cluster-randomised controlled trial of a health literacy program in adult basic education classes across New South Wales, Australia. This paper reports findings from a qualitative study exploring learners' experience of the course and its perceived impact on their lives, as well as their understanding and confidence about health. STUDY TYPE:Qualitative interview study. METHOD:We conducted semistructured interviews as part of the evaluation of the 18-week health literacy program, with participants purposively recruited from six health literacy classes (n = 22). Researchers trained in qualitative methods interviewed adult learners either face to face or over the phone using a topic guide. Data was analysed using the Framework method, a matrix-based approach to thematic analysis. RESULTS:The majority of interviewees were female, lived in metropolitan areas and were from non-English-speaking backgrounds. Most had existing self-reported health problems and inadequate functional health literacy. Most participants described positive impacts of the health literacy course on their language, literacy and numeracy skills, functional health literacy skills, and health knowledge. They also reported being able to translate this into health actions including interacting with providers, accessing and using healthcare, and managing health and illness (e.g. making healthier food choices). Learners also described positive social outcomes of the course, including feelings of connectedness and interpersonal trust within a new network of learners, and reported sharing new knowledge with others in their communities. CONCLUSIONS:The findings add value to existing limited evidence that has demonstrated the untapped potential of adult basic education to develop health literacy skills among socially disadvantaged groups. Learners valued the opportunity to share experiences in structured group learning, and reported confidence to transfer new knowledge into their home and wider social network

Experimental and numerical study of process-induced defects and their effect on fatigue debonding in composite joints

Laboratory coupon joints for fatigue debonding tests usually have narrow width and a through-width initial disbond. However, realistic structural joints are much wider and may contain process-induced defects and accidental damage; both are much smaller than the joint width. Small and discrete damage may behave differently from the idealised through-width disbond crack. This has brought a question on whether the laboratory coupon joint can accurately represent the fatigue behaviour of wider structural joints. This paper presents an experimental and numerical study of fatigue behaviour of a wide bonded lap joint with a process-induced defect of semi-circular shape. Fatigue debonding propagation was monitored by ultrasound inspection. Fatigue life was predicted using a normalised strain energy release rate parameter calculated by finite element method, and the adhesive material fatigue crack growth rate data measured under single and mixed mode conditions. Simulation of process-induced defect and validation by experiments have brought a better understanding of fatigue debonding behaviour in wide joints containing realistic damage. Suggestions are given for fatigue fracture tests of bonded joints

Towards a Framework for Open Data Publishers:A Comparison Study between Sweden and Belgium

Public organizations in the role of publishers publish datafor anyone to reuse, which can lead to benets. However, the processdescriptions for this publishing work focus on one or a few issues, whichleaves out important areas and decisions. Little seems to be known aboutvariations between publishers based on one common point of comparison.Therefore, this paper presents a comparison between two publishers:Namur (Belgium) and Linkoping (Sweden). The comparison is based ona process framework, seven in-depth interviews, document studies, anda verication meeting with one respondent. We learned that the OGD manager is an agent of change who need to balance implementation andguidance, the orthodox method of e-mail registration can be used toengage users and monitor impact, the organizational unit for OGD iscross-organizational, and the publisher process framework could be usedas ex-ante strategic guidelines and context-specic recommendations

Structural packaging foams prepared by uni-directional freezing of paper sludge cellulose nanofibres and poly (vinyl alcohol)

Porous foams from cellulose nanofibres (CNF) and poly-vinyl alcohol CNF/PVA were prepared by uni-directional freezing to create a homogeneous pore structure. The CNF was derived from paper mills sludge (PMS), a by-product of paper manufacturing waste-water treatment. Sodium tetraborate decahydrate (borax) was used as a crosslinking agent. The density of the CNF/PVA foams were 0.03 g cm−3 with a compressive strength of 116 kPa at 20% strain. The foams were competitive to commercial expanded polystyrene (EPS) foam