EFFECTS OF POLY-ALUMINUM CHLORIDE, STARCH , ALUM AND ROSIN ON THE ROSIN SIZING, STRENGTH AND MICROSCOPIC APPEARANCE OF PAPER PREPARED FROM OLD CORRUGATED CONTAINER (OCC) PULP

The influence of rosin (0.1-0.3%), alum (0.4-0.6%), polyaluminum chloride (0.3-0.7%), and starch (0.5-1.5%) in the making of paper from old corrugated container (OCC) pulp on the freeness, breaking length, tear index, and burst index of pulp and paper sheets was studied. Using a full factorial design to identify the optimum operating conditions, equations relating the dependent variables to the operational variables of the chemical additives were derived that reproduced the former with errors lower than 5%. Using a high starch (1.5%), high PAC (0.7%), low alum (0.4%), and low rosin (0.1%) combination led to pulp that was sufficient to obtain paper with good strength properties (breaking length 5720m; burst index: 3.1 kPam2g-1; tear index: 6.2mNm2/g; Cobb test: 94; fold endurance: 1.52) SEM analysis show increasing in bonding between fibers together at this level of additives. The influence of starch on Cobb test values was not significant

EVALUATION OF HARVESTING TIME EFFECTS AND CULTIVARS OF KENAF ON PAPERMAKING

This study investigates the effect of six cultivars named Cubano, Niger, Cubano 2032, 9277, 7551 and, 7566, of kenaf and three harvesting time stages on pulp and handsheet paper properties of kenaf, which were accomplished in north of Iran. Six cultivars of an Iranian kenaf (Hibiscus Cannabinus L.), were planted on 19 May 2007, and harvested at 85, 105, and 135 days after planting. It was understood that with the increase of plant age, the fiber yield increased. Maximum yield at each of three harvesting time stages was related to Niger. Consequently, if a high fiber yield is sought, Niger can be recommended. But if a paper with high strength properties is to be requested, Cubano 2032 is strongly associated with significant burst, tear, breaking length, and fold endurance even though its yield shows a bit lesser than Niger at short harvesting times. Moreover, at second harvesting time stage, maximum strength properties of handsheets such as burst, tear, breaking length, and fold endurance were related to Cubano, though the fiber yield of this cultivar was a bit lesser than Niger, but it was still more than Cubano 2032. In comparison between harvesting time stages, it is clearly understood from the composition of harvesting time of third stage to first and second stage, a minor positive effect on the handsheets properties with increasing harvesting times has appeared

Improving safety in physical human-robot collaboration via deep metric learning

Direct physical interaction with robots is becoming increasingly important in flexible production scenarios, but robots without protective fences also pose a greater risk to the operator. In order to keep the risk potential low, relatively simple measures are prescribed for operation, such as stopping the robot if there is physical contact or if a safety distance is violated. Although human injuries can be largely avoided in this way, all such solutions have in common that real cooperation between humans and robots is hardly possible and therefore the advantages of working with such systems cannot develop its full potential. In human-robot collaboration scenarios, more sophisticated solutions are required that make it possible to adapt the robot’s behavior to the operator and/or the current situation. Most importantly, during free robot movement, physical contact must be allowed for meaningful interaction and not recognized as a collision. However, here lies a key challenge for future systems: detecting human contact by using robot proprioception and machine learning algorithms. This work uses the Deep Metric Learning (DML) approach to distinguish between non-contact robot movement, intentional contact aimed at physical human-robot interaction, and collision situations. The achieved results are promising and show show that DML achieves 98.6% accuracy, which is 4% higher than the existing standards (i.e. a deep learning network trained without DML). It also indicates a promising generalization capability for easy portability to other robots (target robots) by detecting contact (distinguishing between contactless and intentional or accidental contact) without having to retrain the model with target robot data

Influence of hydrothermal treatment on the dimensional stability of beech wood

Hydrothermal treatment of wood material products with many interesting properties such as enhanced dimensional stability, lower equilibrium moisture content and increased biological durability. The effects of hydrothermal treatment on dimensional stability, oven dry density and water absorption of beech wood (Fagus Orientalis) naturally grown, has been studied in present research that extremely used in Iran. Hydrothermal applied to the wood samples (2.5Cm?2.5Cm?2.5Cm) in three different temperatures (150 oC, 160 oC, 170 oC) and four different durations (1h, 3h, 5h and 7h) in reactor. Then, the samples and their controls were immersed in water at 25 oC, 65% relative humidity for various periods. Volumetric swelling percentage and rate of the water absorption values of the samples and their controls were measured at a period of 24 hour in 8 steps on basis of oven dried dimension. The obtained data were analyzed using Microsoft Office (EXCEL 2003). The data analysis indicated that best anti-swelling efficiency value was achieved at 170 oC (treating temperature) within 1 hour (treating time) and 8 steps of soaking - dried measurement by hydrothermal treatment. Consequences for anti-swelling efficiency, decreasing of samples specific gravity, water absorption and water repellency effectiveness values obtained 27.95%, 8.49%, 56.41% and 20.20% respectively. Therefore, hydrothermal treatment showed a little decreasing at 150 oC to 170oC in specific gravity of treatment samples because maximum lessening of specific gravity obtained 8.02% in the highest condition of treatmentDimensional stability after final soaking

A mixed-perception approach for safe human–robot collaboration in industrial automation

Digital-enabled manufacturing systems require a high level of automation for fast and low-cost production but should also present flexibility and adaptiveness to varying and dynamic conditions in their environment, including the presence of human beings; however, this presence of workers in the shared workspace with robots decreases the productivity, as the robot is not aware about the human position and intention, which leads to concerns about human safety. This issue is addressed in this work by designing a reliable safety monitoring system for collaborative robots (cobots). The main idea here is to significantly enhance safety using a combination of recognition of human actions using visual perception and at the same time interpreting physical human–robot contact by tactile perception. Two datasets containing contact and vision data are collected by using different volunteers. The action recognition system classifies human actions using the skeleton representation of the latter when entering the shared workspace and the contact detection system distinguishes between intentional and incidental interactions if physical contact between human and cobot takes place. Two different deep learning networks are used for human action recognition and contact detection, which in combination, are expected to lead to the enhancement of human safety and an increase in the level of cobot perception about human intentions. The results show a promising path for future AI-driven solutions in safe and productive human–robot collaboration (HRC) in industrial automation

Prognostic value of FBXO39 and ETS-1 but not BMI-1 in Iranian colorectal cancer patients

Background: Colorectal cancer (CRC) is one of the most prevalent cancers worldwide. Despite recent progress in diagnosis and treatment, it remains a major health problem and further studies are needed. We here investigated expression profiles of the FBXO39, ETS-1 and BMI-1 genes in CRCs to validate any possible diagnostic/prognostic significance. Material and Methods: Thirty six patients with locally advanced CRC admitted to Hazrate-Rasoul Hospital-Tehran were enrolled. Initially the expression pattern of FBXO39, ETS-1 and BMI-1 genes were determined using RT-PCR in CRC tumor and adjacent normal tissues then real-time RT-PCR was employed to quantify BMI-1 gene expression. Results: FBXO39 expression was restricted to tumor tissues. Interestingly, expression of this gene was detected in all stage-0 tumor samples. There was a significant relation between FBXO39 gene expression and lymph node involvement. The ETS-1 gene was expressed in 66 of all tumor tissues with p-value=0.03 for increase as compared to the adjacent normal samples. In addition, there was a significant relation between ETS-1 gene expression and tumor size and lymph node involvement. RT-PCR demonstrated BMI-1 gene expression in both tumor and normal tissues and quantification by real-time RT-PCR showed no association between BMI-1 levels and CRC clinicopathological features. Conclusion: Expression of FBXO39 and ETS-1 with lymph node involvement may be considered as an alarm for the occurrence of CRC metastasis, and therfore have prognostic value while BMI-1 appears without importance. © 2018 Asian Pacific Organization for Cancer Prevention

Prognostic value of FBXO39 and ETS-1 but not BMI-1 in Iranian colorectal cancer patients

Background: Colorectal cancer (CRC) is one of the most prevalent cancers worldwide. Despite recent progress in diagnosis and treatment, it remains a major health problem and further studies are needed. We here investigated expression profiles of the FBXO39, ETS-1 and BMI-1 genes in CRCs to validate any possible diagnostic/prognostic significance. Material and Methods: Thirty six patients with locally advanced CRC admitted to Hazrate-Rasoul Hospital-Tehran were enrolled. Initially the expression pattern of FBXO39, ETS-1 and BMI-1 genes were determined using RT-PCR in CRC tumor and adjacent normal tissues then real-time RT-PCR was employed to quantify BMI-1 gene expression. Results: FBXO39 expression was restricted to tumor tissues. Interestingly, expression of this gene was detected in all stage-0 tumor samples. There was a significant relation between FBXO39 gene expression and lymph node involvement. The ETS-1 gene was expressed in 66 of all tumor tissues with p-value=0.03 for increase as compared to the adjacent normal samples. In addition, there was a significant relation between ETS-1 gene expression and tumor size and lymph node involvement. RT-PCR demonstrated BMI-1 gene expression in both tumor and normal tissues and quantification by real-time RT-PCR showed no association between BMI-1 levels and CRC clinicopathological features. Conclusion: Expression of FBXO39 and ETS-1 with lymph node involvement may be considered as an alarm for the occurrence of CRC metastasis, and therfore have prognostic value while BMI-1 appears without importance. © 2018 Asian Pacific Organization for Cancer Prevention

Analyse par le plan de phase et optimisation d’un convertisseur résonant CLLC pour chargeur de véhicule bidirectionnel

A bi-directional EV charger is a technology that allows energy to be fed back to the grid from the battery. The electrical requirements of the EV charger are examined in detail to find a suitable power electronics converter to meet the specifications. The CLLC resonant converter is a promising candidate for these applications. The fundamentals of the bi-directional EV charger based on the CLLC resonant converter and its main components are studied in depth. A comprehensive design methodology including the design of all the components of the converter is studied to define an optimization problem corresponding to the objective function and the constraints. The objective function can be considered as maximising efficiency and power density, or minimising mass, volume and losses. Constraints are also highlighted, which are the operating region of the battery charger, the maximum temperature, the maximum RMS current of the resonant cells, the maximum voltage, the soft-switching condition and the continuous conduction mode operation (CCM). A change-of-variables based circuit analysis method is presented that represents the state space equations in two decoupled sets of equations. The analyses are performed in two state-plane coordinate systems and the results are then reprojected to the original region. The proposed method is then used to thoroughly analyse the CLLC resonant converter operating in continuous (CCM) and discontinuous (DCM) conduction modes. The component constraints, zero voltage switching condition, output voltage gain, output characteristic diagram and mode limit of CCM/DCM are then obtained. The accuracy of the proposed approach is verified by simulation and experimentation on a 3.3 kW bi-directional CLLC resonant converter with GaN transistors as primary and secondary side switches. The results confirm the accuracy of the proposed state plane analysis in both power transfer directions.The second objective of this thesis is related to the optimisation of the CLLC resonant converter. The CADES software is used as an optimisation platform and the phase plane analysis is implemented using C++.The optimisation of a resonant converter has been based on the single operating point, which leads to not meeting all the constraints when the converter operates for a different operating point. A new multiple operating point optimisation algorithm is presented. The sequential quadratic programming (SQP) algorithm is adopted to find the optimal results, which requires the derivability of the objective functions and constraints. This implies reasoning in an "imaginary" world as not all parameters are physically implementable. The proposed method optimises the CLLC resonant converter in this imaginary world and then finds the optimal solution in the real world, via a combinatorial approach to the minimum and maximum values of the discrete parameters. The optimisation algorithm is verified using two experimental setups.Un chargeur EV bidirectionnel est une technologie qui permet de renvoyer l'énergie vers le réseau électrique depuis la batterie. Les exigences électriques du chargeur EV sont examinées en détail pour trouver un convertisseur d'électronique de puissance approprié pour répondre au cahier des charges. Le convertisseur résonant CLLC est un candidat prometteur pour ces applications Les principes fondamentaux du chargeur EV bidirectionnel basé sur le convertisseur résonnant CLLC et ses principaux composants sont étudiés en profondeur. Une méthodologie de conception globale comprenant la conception de l'ensemble des composants du convertisseur est étudiée pour définir un problème d'optimisation correspondant à la fonction objectif et aux contraintes. La fonction objectif peut être considérée comme maximisant l'efficacité et la densité de puissance, ou minimisant la masse, le volume et les pertes. Les contraintes sont également mises en évidence, qui sont la région de fonctionnement du chargeur de batterie, la température maximale, le courant RMS maximal des éléments résonants, la tension maximale, la condition de commutation douce et le fonctionnement en mode de conduction continue (CCM). Une méthode d'analyse de circuit basée sur le changement de variables est présentée qui représente les équations de l'espace d'état en deux ensembles découplés d'équations. Les analyses sont effectuées dans deux systèmes de coordonnées de plan d'état, puis les résultats sont reprojetés sur la région d'origine. La méthode proposée est ensuite utilisée pour analyser en profondeur le convertisseur résonant CLLC fonctionnant en mode de conduction continue (CCM) et discontinue (DCM). Les contraintes des composants, la condition de commutation de tension nulle, le gain de tension de sortie, le diagramme de caractéristique de sortie et la limite de mode de CCM/DCM sont ensuite obtenus. La précision de l'approche proposée est vérifiée par la simulation et l'expérimentation sur un convertisseur résonnant CLLC bidirectionnel de 3,3 kW avec des transistors GaN comme commutateurs côté primaire et secondaire. Les résultats confirment la précision de l'analyse du plan d'état proposé dans les deux sens de transfert de puissance.Le deuxième objectif de cette thèse est relatif à l'optimisation du convertisseur résonnant CLLC. Le logiciel CADES est utilisé comme plate-forme d'optimisation et l'analyse du plan de phase y est implémentée à l'aide de C++.L'optimisation d'un convertisseur résonnant a été basée sur le point de fonctionnement unique, ce qui conduit à ne pas respecter toutes les contraintes lorsque le convertisseur fonctionne pour un point de fonctionnement différent. Un nouvel algorithme d'optimisation de points de fonctionnement multiples est présenté. L'algorithme de programmation quadratique séquentielle (SQP) est adopté pour trouver les résultats optimaux, ce qui nécessite la dérivabilité des fonctions objectifs et des contraintes. Ceci implique de raisonner dans un monde "imaginaire" du fait que tous les paramètres ne sont pas physiquement implémentables. La méthode proposée optimise le convertisseur résonnant CLLC dans ce monde imaginaire et ensuite retrouve la solution optimale dans le monde réel, via une approche combinatoire des valeurs minimales et maximales des paramètres discrets. L'algorithme d'optimisation est vérifié à l'aide de deux configurations expérimentales