•A state of the art review of sustainable manufacturing operations scheduling is presented and its shortcomings are outlined.•Characteristics, relevant challenges and issues of sustainable ...manufacturing operations scheduling are analyzed.•A three keys based global typology to position the different contributions in the field is proposed.•The prospects that need urgent attention to bridge the gap between research and industrial needs are analyzed.
Sustainability in manufacturing systems is an urgent requirement for today's manufacturing companies. This paper focuses on sustainable manufacturing operations scheduling, a subject which has been attracting increasing interest from researchers in recent years. This paper presents a state of the art review of this field. First, it characterizes what can be considered as sustainable manufacturing operations scheduling, and introduces the relevant challenges and issues. An analysis of the literature is then proposed, and organized according to three keys. The shortcomings in the literature are then discussed in depth, and subsequently urgent problems that must be solved through research in order to meet industry requirements are pointed out.
The study aimed to identify the risk factors of recurrence in chronic osteomyelitis (COM) and to document the microbiological patterns pre- and intra-operatively and at recurrence, if any.
We ...performed retrospective review on COM patients treated with surgical debridement and a 6-week course of antibiotics. The patients with symptoms of osteomyelitis for at least 6 weeks, present or past episodes of discharging sinus, documentation of bone sequestration in operative notes or preoperative images were included in the study. Patients with symptoms of osteomyelitis < 6 weeks, lack of history of discharging sinus or lack of evidence of sequestration in preoperative images or intraoperative notes were excluded. Logistic regression models were used to assess the impact of risk factors of recurrence. Cohen-Kappa scores were derived to see the concordance between pre-operative and intra-operative isolates and at recurrence.
Totally, 147 COM patients (115 males and 32 females, mean age (33 ± 19) years) were included in this study. Recurrence was noted in 28 patients (19.0%). Polymicrobial growth and extended spectrum beta-lactamase producing Enterobacteriaceae increased the chance of recurrence. Cierny-Mader stage-1, hematogenous aetiology and negative intraoperative culture reduced the chance of recurrence. Concordance between pre-operative and intra-operative cultures was 59.85% (Kappa score 0.526, p < 0.001) and between index surgery and at recurrence was 23.81% (Kappa score 0.155, p < 0.001). Lack of knowledge of causative organism preoperatively did not affect outcome. At mean follow-up (42 ± 15) months, all patients were apparently infection free for at least 1 year.
Polymicrobial growth and multi-drug resistant organisms increase the risk of recurrence in COM. Patients’ age, gender, diabetes mellitus, previous failed treatment, duration of symptoms, haemoglobin, white cell count, C-reactive protein and erythrocyte sedimentation rate at presentation did not have any impact on the recurrence of infection. Pre-operative isolation of organism is of questionable value. Recurrences of infections do occur and are more of re-infections than relapses. Diligent isolation of organism must be attempted even in re-debridements. Even patients with recurrences do well with appropriate debridement and antibiotic therapy.
Non-prosthetic peri-implant fractures and under reported entities and their optimal management strategies are uncertain.
We present two cases of peri-implant fractures of distal humerus with long ...dynamic compression plate in situ. We report for the first time a strategy of implant retention, open reduction with small incision, minimal internal fixation with K-wires and supplementary fixation with bilateral external fixator using Joshi's External Stabilizing System (JESS). Both fractures showed signs of union at three months from surgery. The fixators were removed at four months under sedation and patients were advised aggressive active mobilisation of the elbow. This resulted in sound union of the fracture with preservation of elbow motion without any complications.
We recommend this method, as it is a simple, safe, effective and reproducible technique for management of peri-implant fractures of the humerus.
The paper investigates the effects of production scheduling policies aimed towards improving productive and environmental performances in a job shop system. A green genetic algorithm allows the ...assessment of multi-objective problems related to sustainability. Two main considerations have emerged from the application of the algorithm. First, the algorithm is able to achieve a semi-optimal makespan similar to that obtained by the best of other methods but with a significantly lower total energy consumption. Second, the study demonstrated that the worthless energy consumption can be reduced significantly by employing complex energy-efficient machine behaviour policies.
Statistical quality control based approaches provide tools such as control charts for monitoring process parameters (usually 'physical layer') as well as rules such as the Western Electric Rules for ...detecting anomalies. The design of these charts is based on the statistical properties of the monitored parameters and the anomaly notification is related to the statistical significance of the observed change, the practical significance of the change, i.e. the sensitivity of system to the deviation in the parameter values, is not captured. Monitoring and alerting in the 'planning layers', however, is driven by the practical significance of the detected change as against the statistical significance. Recent developments in the field of supply chain event management have been focusing on providing tools and solutions for addressing these needs of the planning layers - these studies have, to a large extent been ad hoc. In this paper we propose and present parametric charts - a post-optimality-based approach for the design and implementation of monitoring and prioritising strategies for logistical anomalies. Analogous to the quality control charts, the parametric charts have four automatically generated regions, namely, the insensitive, the perturbation, the re-optimisation, and the infeasible, with each region having specific priorities and alarm levels associated with them. The bounds for the regions are based on the practical significance of the detected change as against the statistical significance of the deviation. The proposed approach offers three benefits: (1) it removes the ad hoc-ness associated with the determination of the practical significance as well as the priority given to the different classes of impacts that the system user observes, (2) the time consuming process of entering and fine-tuning the alarm bands and the priorities associated with the different alarm types when the exception analytics systems are installed can be decreased and automated, and (3) it aligns the exception analytics with the specific plans that are being executed. The step-by-step implementation of the charting approach is elucidated through a case study for the production unit at the FAME lab, at the Pennsylvania State University.
Non-invasive mode of clinical testing has created a major impact on the society and finds huge demand in the clinical domain. There are several instances where such approach receives more ...co-operations from the patient. Replacing the traditional practice with such non-invasive procedure requires appropriate clinical investigation and validations, specifically exact location of veins for intravenous applications like venepuncture and other medical procedures. Collection of blood samples for bilirubin test for new-borns, blood sugar level detection also needs a special attention where such non-invasive procedure is highly preferred. Such clinical methodology highly relies on the selection/design of photo sensor and works on the principles of light that gets scattered from the human skin. This specific research study attempts to measure the effect of the photo sensor on the skin reflection and how the properties can be exploited for bilirubin test to detect jaundice for new-borns. Neonatal jaundice often referred as hyperbilirubinemia which indicates the concentration of serum bilirubin levels in blood stream. The higher and lower bilirubin levels can cause irreversible brain damage which is referred as kernicterus. The yellowish spot due to bilirubin deposition in the neonatal skin tissue indicates the presence or absence of jaundice. Several attempts have been made in the recent past to develop non-invasive mode of measuring the blood concentration level for recognition of bilirubin levels. The proposed research study involves in measuring the skin reflectance using photo sensor and to measure the bilirubin concentration in a non-invasive mode. A GaAsP yellow LED with a wavelength of 590nm with TEPT5700 light sensors was applied and Arduino real time processor was interfaced to the circuitry. The system was designed in such a manner that the buzzer activation indicates the severity of the bilirubin concentration. The lab based circuitry was converted in to indigenous prototype and was tested with newborn in a real time mode. The clinical validation was found to be quite promising. It can be concluded that the designed system was found to be more economic and can introduce in the primary healthcare sector.
Intelligent Stethoscope Buvaneshwari, B; Rohinee, NA; Roopkumar, Sahana ...
International journal of biomedical and clinical engineering,
01/2014, Letnik:
3, Številka:
1
Journal Article
Recenzirano
Heart valve disorders are primarily detected by auscultation, technique of listening to heart sounds. A more modern form of this technique is phonocardiography, concerned with the automated acoustic ...recording and processing of heart sounds.This paper presents a method that aims at development of an algorithm to detect common heart valve disorders by processing heart sounds and provision of easy access to patient data via the Internet. The proposed method uses thresholding techniques to determine certain criteria which can detect whether a heart sound recording belongs to a person suffering from valvular heart disease or not, by giving ‘diseased' or ‘not diseased' decisions (S. Ari, K. Sensharma, G. Saha, 2008). The recording in case of a ‘diseased' condition is transmitted to the hospital information system via the Internet, wherein it can be further analyzed by a doctor to diagnose the disease.
Electrocardiogram (ECG) signal monitoring is one of the essential techniques for determining the physiological state of human beings. Long-term ECG monitoring is very much essential for the diagnosis ...and treatment of infrequent arrhythmic episodes. Although, most of the wearable microelectronic ECG implementations employ the well-established surface electrodes technology for bio-potential recordings; they are found to be susceptible to skin irritation and influence the skin-contact impedance to larger extent in long-term monitoring applications. Integration of such sensors into wearable intelligent biomedical clothing is not feasible. This specific research study determines the application of two different conductive textile fabric materials, namely, the woven conductive silver and conductive knitted jersey as dry textile electrodes for ECG biopotential acquisition. The skin-electrode contact impedance measurements for both electrodes presented reduced skin-contact impedance of less than 1 <inline-formula> <tex-math notation="LaTeX">\text{M}\Omega </tex-math></inline-formula>/cm 2 compared to 1-5 <inline-formula> <tex-math notation="LaTeX">\text{M}\Omega </tex-math></inline-formula>/cm 2 as reported in literature. The performance of the proposed textile sensors is evaluated qualitatively through visual inspection and quantitatively using metrics such as power spectral density, kurtosis, baseline wander analysis, and signal-to-noise ratio (SNR). The obtained quantitative measures were compared with standard clinical grade conductive-gel based disposable Ag/AgCl surface electrodes. The simulation and comparison studies showed that, the proposed textile electrodes exhibit acceptable performance for ECG acquisition and in some instances improved performance than the traditional commercial disposable gel-based surface electrodes.
Distributed arrival time control (DATC) is a heuristic feedback control algorithm for scheduling which has been developed for a real-time distributed scheduling of heterarchical systems. It has been ...renowned not only for its fast solution searching algorithm but also for its flexibility to changing environment. However, the optimality of this heuristic method has not been analytically explained until recently because it has been designed to discover a near optimal solution instead of the true optimum. In this paper, we provide a novel optimal search method for the DATC scheduling problem by introducing a scalar cost function over the vector space of time and show the existence and location of true optima for the DATC scheduling problem through geometric approach. This geometrical interpretation enables us to find the true optimal by direct projection without iterations like previous DATC approaches. Based on the true optimum found, we evaluate the optimality of DATC algorithms by examining their dependency on initial conditions and explain their intrinsic causality mechanism for the discrepancy with true optimum. The implication of this study is on the new viewpoint over the vector space of DATC, which not only solves the optimality issue of DATC but also provides a new direction of direct search approach like projection method for the true optimum.
Assembly sequence planning plays a major role in the manufacturing industry. There are still many challenges in the area of assembly planning. One of the significant reasons is the weakness in ...effective description of assembly knowledge and information. With the purpose of reducing computational complexity, this paper presents a method based on engineering knowledge approach to the assembly sequence planning. The DACG (Directed Assembly Connection Graph) proposed provides an appropriate way to express both geometric information and non-geometric knowledge. In order to increase the assembly planning efficiency, the DACG includes engineering knowledge and semantic in design, manufacturing and assembly fields. Product semantic information model could offer much useful information for designer to finish the assembly (process) design and make right decision in that process. A product assembly planning example is presented to illustrate the effectiveness of the proposed approach. Preliminary experience with the approach indicates the potential to reduce lead times and thereby can help in completing new product launch projects on time.
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