bluuebunny/crossref_metadata_2025 huggingface dataset:
Method of substantiation of risks insurance of a classification society related to the vendors certification
Authors: Lyubchenko V.O. , Postan M.Ya.
Published: December 2018

In our paper, the methodical approach is proposed for risks minimization of classification society (CS) related to providing the low quality service by recognized vendors. For example, above vendors provide measurement of residual thicknesses of hull, radio expertise, underwater observations, etc. Safe operation of a ship is immediately determined by qualitative and reliable action of vendors.

The method is worked out for optimization of  quality level of services providing  to CS by the vendors which allows us to assess reliability and qua-lity of vendors’ work, and the methodical approach for expediency of risks    insurance determination is proposed, as well. This methodical approach is based on the methods of mathematical reliability theory and evaluation of fai-lures probabilities of some subsystems of ship under operation. It is assumed that quality of vendors work is determined by the volumes of works for each subsystem. The optimization problem is formulated for determination of these volumes which minimize the total average cost for ship observation  by vendors and liquidation of failures sequences. The criterion of insurance expediency  of  failures risk  for the ship under operation (between two neighbor examinations) is formulated. The method is illustrated by numerical results.
Corporate management systems by logistic companies in modern conditions of organizational structures transformation
Authors: Smrkovskаyа V.Yu. , Myroliubova T.E.
Published: December 2018

In the article reasons of transformation of organizational structures of enterprises of different spheres of activity are investigational in general and logistic − in particular in the modern terms of market economy. It is well-proven that expansion of borders of enterprises and passing to the flexible structure of management provide competitive edges. The corporate informative systems are the necessary condition of creation of network enterprises providing single informative space for all his participants.
Investigation of the cyclic strength of deposited parts, hardened by ultrasonic shock processing
Authors: Stalnichenko O.I.
Published: December 2018

The possibilities of application of ultrasonic shock treatment for hardening of parts restored by surfacing are investigated. The results of a study of cyclic durability on samples of steel 35 Ø 27 and 70 mm. Strengthening is given by UUO, which makes it possible to increase the endurance limit to the level of the parent metal.
Rational methods of load swing damping, arising from the operation of cranes
Authors: Nemchuk A.O. , Streltsov P.M.
Published: December 2018

Methods of calculation of some kinds  of control  of trolley transported cargo on the rope with varying length  which  provide dampening of cargo sway and contain minimal quantity of switching of the control parameter are regarded.

Automatic realization of such kinds of control must provide high enough productivity, diminish fatigue and preserve rated working time of the loader.
Designing a biocompatible ear implant of a man with help of modern information technologies
Authors: Savielieva Olena , Orel Leonid , Pavlyshko Andrey , Rutska Veronika
Published: December 2018

The article is devoted to designing a biocompatible human ear implant with the further possibility of its bioprinting. The paper considers 3D technologies used in medicine, the latest trends in the development of 3D bioprinters. The methods of modeling the human ear using the Artec Spider 3D scanner and the patient's digital image are considered. Using these methods, 3D modeling in the software package Autodesk 3ds Max and a solid 3D model of the human ear. 3D-bioprinting is an offensive step for the 3D-friend, which is widely to be visualized in medical. Through the rapid creation of high-precision products, taking into account the specifics of anatomy and pathology of the patient - improve the efficiency and quality of medical care. It will save a lot of lives and, possibly, in time, will improve the organs themselves. Getting a good three-dimensional model plays a big role in the correct form of the printed ears of the patient.
Form Follows Function; Act Follows Form How the Form and Shape of Our Objects Affect Our Behaviour
Authors: Váli István Frigyes
Published: December 2018

The objects we plan, form and shape also shape our lives. From the smallest human-made objects such as a city map to the biggest such as a city, they all have a bearing on our lives. They make a major impact on the way we feel and on our physical and mental health. This paper approaches the matter through different examples, primarily looking at the effects made by the form and shape of objects. A look at the use of our everyday objects shows in what ways and to what extent the different planning methods and principles may affect our habits and lives, how they serve society and what unexpected side-effects they may have at times. Harry Beck's Tube Map from 1933, the Legible London way-finding system, and Terminal 3 of Narita International Airport are fine examples of the possible links between the forms and uses of objects. The analysis sheds some light on the importance of cooperation between disciplines, in both planning and architect training.
Enhancing Energy Security through Utilization of Local Resources
Authors: Adiwibowo Indradarma , Lestari Dita Anggun , Manalu Davit
Published: December 2018

Remote rural villages in Indonesia do not have sufficient infrastructure to maintain an economically sound energy generation and distribution. Sparse area and low population hinder national electricity company PLN (Perusahaan Listrik Negara) to connect these remote rural villages to the national grid. Most of the villages lie in the palm oil plantation, where renewable biomass resources from the Palm Oil Mill wastes are plentiful. Untapped biomass resources could be the answer to energy security issue in the remote rural area. Berau Regency in East Kalimantan Province has many villages located in the palm oil plantation area. Nearly all of the palm oil processing plants in Berau use palm shell and fiber to power the mill. Some of them have the agreement with PLN to sell their excess power. This scheme can be applied to provide electricity to villages around the palm oil mills. However, it is unreliable since the amount of excess electricity produced keeps fluctuating. This paper explores the idea of village-owned biomass/biogas power plant that is owned and operated by the villagers themselves. That way, the village can ensure its energy security using sustainable local resources. In conclusion, the investment cost of biomass/biogas power plant cannot be provided by village annual budget. Although the villages in Berau Regency have a relatively high annual budget, wich is about Rp2 billion to Rp5 billion, the investment costs of biomass/biogas power plant is even higher. According to the economic analysis of biomass/biogas power plant development, a biomass power plant with 1,7 MW capacity can cost up to Rp46 billion. Moreover, a biogas power plant with 1 MW capacity costs around 41 billion. It is not possible for the villages to finance the power plant development by themselves. Therefore, the private sector is needed to implement biomass/biogas utilization for rural electrification from palm oil waste. With the Net Present Value (NPV) up to Rp 65.078.072.000,00 and Internal Rate of Return (IRR) of 20% for biomass power plant and Rp14.330.070.000,00 and 10% for biogas power plant, it is economically feasible and profitable for private enterprise to undertake. The challenges are for the government to encourage the private sector to invest and for PLN to sign Power Purchase Agreement with these palm oil enterprises rather than just Excess Power Agreement.

JEL Classification: I39Keywords: Biomass, biogas, renewable energy, palm oil waste utilization
Myocardial Ischemia Detection from Slope of ECG ST Segment
Authors: Farhan Md Soumik , Nahiyan KM Talha
Published: December 2018

Myocardial ischemia occurs when blood flow to heart is reduced preventing it from receiving enough oxygen. It is a possible indication of partial or complete blockage of coronary arteries. Though ischemia is accompanied by symptoms (fatigue, chest pain, shortness of breath etc.) sometimes it can be silent. If not treated, it can lead to various heart diseases. Most importantly it can progress to myocardial infarction (heart attack), which can be fatal. Thus detecting ischemia at an early stage is important to prevent serious implications. Nowadays personal healthcare monitoring systems are used which provide vital physiological information. In future ECG measurement devices would also be common in homes. So, the proposed work intends to develop an algorithm in detecting myocardial ischemia from ECG, which would be computationally less complex and easy to implement in homecare ECG devices. One way to do it is through continuous or long term monitoring of ECG. The ST segment elevation (or depression) indicates presence of ischemia. The proposed method measures slope of ST segment which must vary in case of ST changes. The algorithm is tested on selected records of the European ST-T database and returns an accuracy of 83.33%.Bangladesh Journal of Medical Physics Vol.10 No.1 2017 12-24
Effect of top cover tilt angle with ground surface on productivity of basin type solar distillation unit
Authors: Begum Hosney Ara , Yousuf M Abu , Rabbani K Siddique E
Published: December 2018

Basin type solar stills were made with two types of top cover, transparent PVC sheet and another with glass sheet. A soaked black towel was at the base which was heated through green-house effect and contributed to the water for distillation. Productivity of these two basin type solar stills were studied at different tilt angles of the top transparent cover with ground surface (13o, 23o and 35o). The average amount of distilled water produced increased with the tilt angles for both types of cover materials, that for glass being much higher than that for PVC cover.Bangladesh Journal of Medical Physics Vol.10 No.1 2017 40-46
Chikungunya – an emerging infection in Bangladesh
Authors: Islam MN
Published: December 2018

Abstract not availableTAJ 2016; 29(2): i
Occurrence of Allergic Contact Dermatitis in Rajshahi City and its relation with some of the socio-demographic characteristics
Authors: Hossain ZMM , Mansur MH Ali
Published: December 2018

There is no detailed and updated data on Allergic Contact Dermatitis (ACD) in our country. The present study is designed in thissituation to reveal the occurrence of allergic contact dermatitis in Rajshahi city and its association with some of the socio-demographic characteristics like sex, socio-economic status, co-morbidity etc.It was a cross-sectional type of descriptive study, conducted upon the general population of urban community of Rajshahi City. 153 respondents were randomly selected of which 76 were male and the rest 77 were female. People of all the ages and all the family members of the selected areas were included in the study, who were present at home at the time of data collection. Data were collected by face-to-face interview with the help of a semi-structured questionnaire. Allergic contact dermatitis was clinically diagnosed by the researchers themselves by direct physical examination after obtaining their symptoms, with the help of common medical equipments like a magnifying glass, a torch etc. Verbal consents were taken for ethical consideration. Occurrence of allergic contact dermatitis was found to be 20.26% in the urban community of Rajshahi City of which 18.42% were male and 22.08% were female – statistically no significant difference was there. Among the different socio-economic status, the middle class had the highest occurrence rate (28.41%) and Chi-square test showed here statistically significant difference between the groups [X2 = 10.591, df=2, p=0.00501411]. The co-morbidity was found to be higher in female respondents with a statistically significant difference [X2 = 5.231 , df = 1, p = 0.02218777].TAJ 2016; 29(2): 42-46
Acute Poisoning – A Neglected Topic
Authors: Islam Mohammad Rafiqul
Published: December 2018

Abstract not availableTAJ 2017; 30(1): i
Thyroid Autoimmunity is a Risk Factor for Recurrent Pregnancy Loss
Authors: Sultana Sharmin , Shamima Mosammat Nargis , Jesmin Sahela , Zahan Nargis , Zahid Md Abu , Hossain Mohd Alamgir , Mahmuda Shahin
Published: December 2018

This was a hospital based case control study. The study included patients attending in outdoor and indoor Department of Obstetrics and Gynaecology of Rajshahi Medical College, Hospital since July 2014 to June 2016. The aim of this study was to determine thyroid antibodies is a risk factor for recurrent pregnancy loss. Sixty seven pregnant or non pregnant women with history of recurrent miscarriage during 1st trimester were selected as case group and another sixty seven pregnant women who reached their 12 weeks uneventfully with no history of recurrent miscarriage were selected as control group. Patients with other cause of recurrent miscarriage such as metabolic or endocrinologic disorders, genital organ anomaly, uterine fibroid were excluded from the study. Thyroid function test and thyroid antibodies (FT4, TSH and TPO-Ab) were measured for the two groups. The result of this study showed that the percentage of positive TPO-Ab in target and control group is 67.16% and 5.95% respectively. The study observed that the mean serum concentrations of FT4 in the control subject was significantly higher than the mean of the target group (p-value <0.05). The TSH concentration was increased in miscarriage women with positive antibodies compared with the concentration of TSH in the control group with positive antibodies. The conclusions are that there is a deficiency in thyroid hormones or thyroid’s functional capacity is unable to meet the extra demands of pregnancy which may be one of the causes of recurrent miscarriage. Moreover positive thyroid antibodies pregnant women can reach term and have babies when the concentration of TSH is low during the first trimester, so the risk of miscarriage could be high in positive thyroid antibodies.TAJ 2017; 30(1): 49-55
The Hayman Technique: A Simple Method to Treat Postpartum Hemorrhage due to Placenta Praevia
Authors: Jesmin Shahela , Borna Nishat Anam , Shamima Mosammat Nargis , E Khuda Iftekhar Md Kudrate , Mahmuda Shahin
Published: December 2018

Aim: To assess effectiveness of Hayman suture to control postpartum haemorrhage due to placenta praevia during caesarean sectionMethods: It is a cross sectional observational study performed in Rajshahi Medical College Hospital, tertiary level hospital, from January 2016 to December 2016. It included 32 patients with PPH following placenta praevia during elective& emergency caesarean section (C/S). All 32 patients underwent horizontal compression suture (bilateral anteroposterior compression) of lower uterine segment. Vicryl 0 tapercut needle was used. All patients were followed postpartum for evaluation of uterine cavity and menstrual cycles.Results Hayman suture was applied in 32 cases. In 27 cases Hayman suture was the only intervention. Hayman with uterine artery ligation required in 2 cases. In 1 patient along with Hayman B-lynch compression suture was given and 2 patients required total hysterectomy.Conclusion: The quick and simple Hayman technique seems to be effective, safe, lifesaving method in stopping hemorrhage due to placenta praevia.TAJ 2017; 30(1): 66-69
The Patient’s Call Versus the Patient’s Well Being
Authors: Hussain AA Mamun
Published: December 2018

Abstract not availableTAJ 2017; 30(2): i
Reconstruction of Basal Cell Carcinoma over Face by Facial Flaps –Study of 30 Cases
Authors: Ghosh Subrata , Chowdhury Milon Kumar , Biswas Nripendra Nath , Sarkar Sunandita , Sarkar Anindita , Chandra Pampa
Published: December 2018

Background: Basal cell carcinoma (BCC) is the most common skin cancer.85% of BCC are located in the head and neck area, of which 30% on the nose. After excision of BCC on the face, the options of treatment for a skin defect are variable. Many surgeons prefer to use a local flap rather than skin graft or free flap for small or moderately sized circular defects after excision of BCC on the face.Methods: All of the patients were histopathologically diagnosed as Basal cell carcinoma, thirty patients underwent various flaps like V-Y advancement flap, bilobed flap, forehead flap, nasolabial flap, glabellar flap repair over 3 years, between January 2014 to December 2016. We observed post-operative complications as flap loss either partial or complete, wound dehiscence, hematoma and wound infection and recurrence of carcinoma. The cosmetic outcome of the face also evaluated.Results: There were 19 men and 11 women. The age ranged from 48 to 73 years with a mean age of 62 years. The causes were BCC in all cases. The tumour locations were the face in all patients. All of the flaps survived, but in one case recurrence of BCC occur, which was managed surgically. Post-operative recovery was very nice.Conclusions: Our study shows facial flaps give nice result and first choice for facial reconstruction in BCC of face. Most defects can best closed by various facial flaps and outstanding functional and cosmetic results can be achieved.TAJ 2017; 30(2): 20-25
Undescended Testes in Children: Clinicopathological Study of 32 Cases
Authors: Islam Syed Sirajul , Hassan Parvez , Ali Md Nawshad , Shahid Shah Md Ahsan , Badruddoza SM , Ahmed Mostaque
Published: December 2018

Objective: To study the presentation, management, histopathological findings and outcome of undescended testes in children. Method: It was a prospective study done in Rajshahi Medical College Hospital and also private clinic in Rajshahi Metropolitan City during the period of 1st December, 2007 to June, 2010. Thirty two children aged 4 months to 13 years with 40 undescended testes were selected in this study. Interventions like Orchidopexy, orchidectomy, herniotomy were done.Results: The age at surgery was four months to 13 years (mean 5.25 + 0.61 SE years). Nine (28.13%) had corrected before two years, twenty three (71.87%) after two years. Twenty four testes (60%) were palpable and sixteen (40%) were non-palpable, none of then cases was diagnosed at birth. Ultrasonography was performed in all cases. Evaluation was done by clinical, sonological, pre-operation and histopathological findings, Laparoscopy was done in one case. The condition was unilateral in 24(75%) and bilateral in Eight (25%). Forty percent of the testes were in the inguinal canal, 34% at the external ring and 10% at the internal ring and 16% in the abdomen. Fifteen (46.87%) testes were macroscopically smaller in size, four (10%) testes were atrophic (all were canalicular), one was tumour. Orchidopexy was performed in for 35 undescended testes and orchidectomy for five. Scrotal haematoma developed in 2 cases. Histopathological finding showed no spermatogonia in 25 (78.12%), among then 23 were above 2 years, 2 were below 2 years. Follow-up period were 6 months to 18 months, no atrophy/retraction was observed.TAJ 2017; 30(2): 26-31
Evaluation of Skeletal Metastases in Different Clinical Stages of Breast Cancer Patients
Authors: Hosen MM Arif , Uddin Md Dayem , Zerin Ipshita , Begum Nasrin , Mutsuddy Pupree , Anam Sunny , Shimu Farjana , Sharkar Julekha
Published: December 2018

Background: Breast cancer is a common form of cancer among women globally. Bone is the most common site to which breast cancer metastasizes. Between 30% and 85% of patients with metastatic breast cancer will develop bone metastases during the course of the disease.Objective: To evaluate the pattern and distribution of skeletal metastases in different clinical stages of breast cancer patients by using Tc-99m MDP bone scan.Materials and methods: A retrospective study was conducted on 305 consecutive female breast carcinoma patients referred for bone scan to Institute of Nuclear Medicine and Allied Sciences, Rajshahi from January 2015 to June 2017. All patients were categorized in one of the three groups; early breast cancer (EBC, comprises clinical stage I and II), locally advanced breast cancer (LABC, clinical stage III) and metastatic breast cancer (MBC, clinical stage IV). Bone scan was performed by an intravenous bolus injection of 20 mCi Tc99m-MDP and bone phase images were taken at three hours after injection of the radiotracer.Results: Out of 305 studied patients, 16 patients (5.25%) were in EBC group, LABC patients were 173 (56.72%) and MBC were 116 (38.03%). 98 patients (32.13%) were positive for skeletal metastases. In 16 EBC patients only 01 patient (6.25%) had skeletal metastasis in thoracic spine. Skeletal metastases were 20.81% in LABC and 52.59% in MBC group. Thoraco-lumbar spine was the commonest site in both groups followed by ribs, pelvic bones, upper and lower extremities, cervical spine, sternum, scapula and skull bone.Conclusion: Bone scan should be done in all LABC and MBC patients and in symptomatic EBC at disease presentation. Parts of bone to focus are thoracic and lumbar spine in all stages, followed by ribs, pelvis and extremities. Tc-99m MDP bone scan play a major role in early detection of skeletal metastasis in breast cancer patients.TAJ 2017; 30(2): 47-53
Invasive Aquatic Plants as Ecosystem Engineers in an Oligo-Mesotrophic Shallow Lake
Authors: Ribaudo Cristina , Tison-Rosebery Juliette , Buquet Damien , Jan Gwilherm , Jamoneau Aurélien , Abril Gwenaël , Anschutz Pierre , Bertrin Vincent
Published: December 2018

Exotic hydrophytes are often considered as aquatic weeds, especially when forming dense mats on an originally poorly colonized environment. While management efforts and research are focused on the control and on the impacts of aquatic weeds on biodiversity, their influence on shallow lakes’ biogeochemical cycles is still unwell explored. The aim of the present study is to understand whether invasive aquatic plants may affect the biogeochemistry of shallow lakes and act as ecosystem engineers. We performed a multi-year investigation (2013–2015) of dissolved biogeochemical parameters in an oligo-mesotrophic shallow lake of south-west of France (Lacanau Lake), where wind-sheltered bays are colonized by dense mats of exotic Egeria densa Planch. and Lagarosiphon major (Ridl.) Moss. We collected seasonal samples at densely vegetated and plant-free areas, in order to extrapolate and quantify the role of the presence of invasive plants on the biogeochemistry, at the macrophyte stand scale and at the lake scale. Results revealed that elevated plant biomass triggers oxygen (O2), dissolved inorganic carbon (DIC) and nitrogen (DIN) stratification, with hypoxia events frequently occurring at the bottom of the water column. Within plants bed, elevated respiration rates generated important amounts of carbon dioxide (CO2), methane (CH4) and ammonium (NH4+). The balance between benthic nutrients regeneration and fixation into biomass results strictly connected to the seasonal lifecycle of the plants. Indeed, during summer, DIC and DIN regenerated from the sediment are quickly fixed into plant biomass and sustain elevated growth rates. On the opposite, in spring and autumn, bacterial and plant respiration overcome nutrients fixation, resulting in an excess of nutrients in the water and in the increase of carbon emission toward the atmosphere. Our study suggests that aquatic weeds may perform as ecosystem engineers, by negatively affecting local oxygenation and by stimulating nutrients regeneration.
Application of a Nonlinear Hammerstein-Wiener Estimator in the Development and Control of a Magnetorheological Fluid Haptic Device for Robotic Bone Biopsy
Authors: Shokrollahi Elnaz , Goldenberg Andrew A. , Drake James M. , Eastwood Kyle W. , Kang Matthew
Published: December 2018

A force generator module (FGM) based on magnetorheological fluid (MRF) was developed to provide force-feedback information for applications in tele-robotic bone biopsy procedures. The FGM is capable of rapidly re-producing a wide range of forces that are common in bone biopsy applications. As a result of the nonlinear nature of MRF, developing robust controllers for these mechanisms can be challenging. In this paper, we present a case study motivated by robotic bone biopsy. We use a non-linear Hammerstein-Wiener (H-W) estimator to address this challenge. The case is presented through three studies. First, an experiment to develop design constraints is presented and describes biopsy force measurements for various animal tissues. Required output forces were found to range between <1 N and <50 N. A second study outlines the design of the FGM and presents the experimental characterization of the hysteretic behavior of the MRF. This data is then used as estimators and validators to develop the nonlinear Hammerstein-Wiener (H-W) model of the MRF. Validation experiments found that the H-W model is capable of predicting the behavior of the MRF device with 95% accuracy and can eliminate hysteresis in a closed-loop control system. The third study demonstrates the FGM used in a 1-DOF haptic controller in a simulated robotic bone-biopsy. The H-W control tracked the input signal while compensating for magnetic hysteresis to achieve optimal performance. In conclusion, the MRF-based device can be used in surgical robotic operations that require a high range of force measurements.
Numerical and Experimental Investigations of a Micromixer with Chicane Mixing Geometry
Authors: Khaydarov Valentin , Borovinskaya Ekaterina S. , Reschetilowski Wladimir
Published: December 2018

A micromixer is a new type of chemical engineering equipment used to intensify the mixing process. This article provides details on flow regimes in microchannels with a complex geometry, such as with chicane mixing geometry. Experiments involving water, ink, and a micro digital camera have determined both the micromixer’s initial mixing zone, and also the streamlines. Computational fluid dynamics (CFD) modelling helped identify the mechanism of stimulating effect; swirling and recirculation were identified as two special cases of the convective mixing process. To characterize the degree of mixing, a function of volume flow rate was proposed. A much higher degree of mixing in vortex flow compared to stratified flow was observed. The relationship between laminar flow and vortices shows a square-law dependence of pressure drop against the volume flow rate. The mixing cost and the mixing energy cost at Reynolds number of 50 are higher for the chicane micromixer than for micromixers without chicanes geometry.
Photocatalytic Oxidation of Toluene on Fluorine Doped TiO2/SiO2 Catalyst Under Simulant Sunlight in a Flat Reactor
Authors: Qiu Lu , Wang Yanan , Li Hanlinag , Cao Gang , Ouyang Feng , Zhu Rongshu
Published: December 2018

Improving the capacity of TiO2 semiconductors for visible light response is a key problem for utilization of solar energy in photo-catalytic degradation of organic pollutants. Both catalyst character and reactor conditions are important for the reaction efficiency. The fluorine ion doped TiO2/SiO2 catalyst was prepared by sol-gel method using HF solution as fluorine source. The activity test and UV–vis results indicated that this catalyst was superior to TiO2 P25 in photocatalytic oxidation of gaseous toluene under simulant sunlight irradiation due to the enhancement of visible and ultraviolet light absorbance. GC-MS results indicated that the main intermediates accumulated on active sites included benzoic acid, benzaldehyde, and phenol. A flat interlaid reactor was designed for continuous treatment of the stream with F-TiO2/SiO2 film. The results showed that coating the catalyst on the surface of both top and bottom glass substrates, through the knife coating method with an optimal reactor height, attained the highest efficiency. In addition, the presence of water and oxygen enhanced the oxidation of toluene due to the generation of hydroxyl radicals and peroxy radicals, respectively. The toluene oxidation rate increased with the increase in water vapor concentration in the range of 0~60 vol.%.
Steam vs. Dry Reformer: Experimental Study on a Solid Oxide Fuel Cell Short Stack
Authors: Barelli Linda , Bidini Gianni , Cinti Giovanni
Published: December 2018

Solid Oxide Fuel Cell (SOFC) systems operating with methane usually are equipped with an external reformer to produce syngas. The conventional applied technology is steam methane reforming. Recent studies, instead, are presenting dry reforming as potential alternative. Advantages come from the substitution of steam with CO2 to be handled in the system, representing a potential strategy of CO2 reuse. This study compares, the performance of a SOFC short stack operating with dry reforming and with steam reforming mixtures respectively. Results show that higher performances can be obtained under same operating conditions, due to the high concentration of syngas (that has low content of inert species) produced via dry reforming. The analysis of different dry reforming concentrations shows that the amount of methane seems to be more relevant, in terms of voltage performances, than high hydrogen concentration. Among tested dry reforming compositions, the most performing exhibits an improvement of at least 5% in produced voltage in the range 150–375 mA cm−2 with respect to mixture produced by steam reforming (S/C ratio of 2.5). It was also proved that this performance enhancement does not imply greater thermal stresses, since stack temperature slightly reduces and lower temperature variations arise at anode and cathode when operating current varies.
Maximizing Anhydrosugar Production from Fast Pyrolysis of Eucalyptus Using Sulfuric Acid as an Ash Catalyst Inhibitor
Authors: Zhang Dongyan , Fan Yuyang , Zheng Anqing , Zhao Zengli , Wang Fengyun , Li Haibin
Published: December 2018

Anhydrosugars, such as levoglucosan (LG), are high value-added chemicals which are mainly derived from fast pyrolysis of pure cellulose. However, fast pyrolysis of raw lignocellulosic biomass usually produces a very low amount of levoglucosan, since alkali and alkaline earth metals (AAEM) present in the ash can serve as the catalysts to inhibit the formation of levoglucosan through accelerating the pyranose ring-opening reactions. In this study, eucalyptus was impregnated with H2SO4 solutions with varying concentrations (0.25–1.25%). The characteristics of ash derived from raw and H2SO4-impregnated eucalyptus were characterized by X-ray fluorescence spectroscopy (XRF) and X-ray diffraction (XRD). The pyrolysis behaviors of raw and H2SO4-impregnated eucalyptus were performed on the thermogravimetric analysis (TGA) and pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS). TG analysis demonstrated that the H2SO4-impregnated eucalyptus produced less char than raw eucalyptus. Py-GC/MS analysis showed that even small amounts of H2SO4 can obviously improve the production of anhydrosugars and phenols and suppressed the formation of carboxylic acids, aldehydes, and ketones from fast pyrolysis of eucalyptus. The rank order of levoglucosan yield from raw and impregnated eucalyptus was raw < 1.25% H2SO4 < 1% H2SO4 < 0.75% H2SO4 < 0.25% H2SO4 < 0.5% H2SO4. The maximum yield of levoglucosan (21.3%) was obtained by fast pyrolysis of eucalyptus impregnated with 0.5% H2SO4, which was close to its theoretical yield based on the cellulose content. The results could be ascribed to that H2SO4 can react with AAEM (e.g., Na, K, Ca, and Mg) and lignin to form lignosulfonate, thus acting as an inhibitor to suppress the catalytic effects of AAEM during fast pyrolysis of eucalyptus.
MicroRNA-Regulated Rickettsial Invasion into Host Endothelium via Fibroblast Growth Factor 2 and Its Receptor FGFR1
Authors: Sahni Abha , Narra Hema P. , Patel Jignesh , Sahni Sanjeev K.
Published: December 2018

Microvascular endothelial cells (ECs) represent the primary target cells during human rickettsioses and respond to infection via the activation of immediate–early signaling cascades and the resultant induction of gene expression. As small noncoding RNAs dispersed throughout the genome, microRNAs (miRNAs) regulate gene expression post-transcriptionally to govern a wide range of biological processes. Based on our recent findings demonstrating the involvement of fibroblast growth factor receptor 1 (FGFR1) in facilitating rickettsial invasion into host cells and published reports suggesting miR-424 and miR-503 as regulators of FGF2/FGFR1, we measured the expression of miR-424 and miR-503 during R. conorii infection of human dermal microvascular endothelial cells (HMECs). Our results revealed a significant decrease in miR-424 and miR-503 expression in apparent correlation with increased expression of FGF2 and FGFR1. Considering the established phenomenon of endothelial heterogeneity and pulmonary and cerebral edema as the prominent pathogenic features of rickettsial infections, and significant pathogen burden in the lungs and brain in established mouse models of disease, we next quantified miR-424 and miR-503 expression in pulmonary and cerebral microvascular ECs. Again, R. conorii infection dramatically downregulated both miRNAs in these tissue-specific ECs as early as 30 min post-infection in correlation with higher FGF2/FGFR1 expression. Changes in the expression of both miRNAs and FGF2/FGFR1 were next confirmed in a mouse model of R. conorii infection. Furthermore, miR-424 overexpression via transfection of a mimic into host ECs reduced the expression of FGF2/FGFR1 and gave a corresponding decrease in R. conorii invasion, while an inhibitor of miR-424 had the expected opposite effect. Together, these findings implicate the rickettsial manipulation of host gene expression via regulatory miRNAs to ensure efficient cellular entry as the critical requirement to establish intracellular infection.
Multi-Agent Big-Data Lambda Architecture Model for E-Commerce Analytics
Authors: Pal Gautam , Li Gangmin , Atkinson Katie
Published: December 2018

We study big-data hybrid-data-processing lambda architecture, which consolidates low-latency real-time frameworks with high-throughput Hadoop-batch frameworks over a massively distributed setup. In particular, real-time and batch-processing engines act as autonomous multi-agent systems in collaboration. We propose a Multi-Agent Lambda Architecture (MALA) for e-commerce data analytics. We address the high-latency problem of Hadoop MapReduce jobs by simultaneous processing at the speed layer to the requests which require a quick turnaround time. At the same time, the batch layer in parallel provides comprehensive coverage of data by intelligent blending of stream and historical data through the weighted voting method. The cold-start problem of streaming services is addressed through the initial offset from historical batch data. Challenges of high-velocity data ingestion is resolved with distributed message queues. A proposed multi-agent decision-maker component is placed at the MALA stack as the gateway of the data pipeline. We prove efficiency of our batch model by implementing an array of features for an e-commerce site. The novelty of the model and its key significance is a scheme for multi-agent interaction between batch and real-time agents to produce deeper insights at low latency and at significantly lower costs. Hence, the proposed system is highly appealing for applications involving big data and caters to high-velocity streaming ingestion and a massive data pool.
Optimized Adaptive Local Iterative Filtering Algorithm Based on Permutation Entropy for Rolling Bearing Fault Diagnosis
Authors: Lv Yong , Zhang Yi , Yi Cancan
Published: December 2018

The characteristics of the early fault signal of the rolling bearing are weak and this leads to difficulties in feature extraction. In order to diagnose and identify the fault feature from the bearing vibration signal, an adaptive local iterative filter decomposition method based on permutation entropy is proposed in this paper. As a new time-frequency analysis method, the adaptive local iterative filtering overcomes two main problems of mode decomposition, comparing traditional methods: modal aliasing and the number of components is uncertain. However, there are still some problems in adaptive local iterative filtering, mainly the selection of threshold parameters and the number of components. In this paper, an improved adaptive local iterative filtering algorithm based on particle swarm optimization and permutation entropy is proposed. Firstly, particle swarm optimization is applied to select threshold parameters and the number of components in ALIF. Then, permutation entropy is used to evaluate the mode components we desire. In order to verify the effectiveness of the proposed method, the numerical simulation and experimental data of bearing failure are analyzed.
Computational Simulation of Entropy Generation in a Combustion Chamber Using a Single Burner
Authors: Morsli Souad , Sabeur Amina , El Ganaoui Mohammed , Ramenah Harry
Published: December 2018

In this study, we examine the behavior of a propane diffusion flame with air in a burner; the computational investigations are achieved for each case employing the Fluent package. The graphs generated illustrate the influence of flow parameters, the effects of the oxygen percentage in the air, and the effects of the equivalence ratio φ on the entropy generation, the temperature gradients, and the Bejan number. The obtained results show that incorporation of hydrogen with propane reduced both temperature and carbon monoxide emission.
Characterization of a Fast Battery Energy Storage System for Primary Frequency Response
Authors: Stein Karl , Tun Moe , Matsuura Marc , Rocheleau Richard
Published: December 2018

In response to increasing integration of renewable energy sources on electric grid systems, battery energy storage systems (BESSs) are being deployed world-wide to provide grid services, including fast frequency regulation. Without mitigating technologies, such as BESSs, highly variable renewables can cause operational and reliability problems on isolated grids. Prior to the deployment of a BESS, an electric utility company will typically perform modeling to estimate cost benefits and determine grid impacts. While there may be a comparison of grid operations before and after BESS installation, passive monitoring typically does not provide information needed to tune the BESS such that the desired services are maintained, while also minimizing the cycling of the BESS. This paper presents the results of testing from a live grid using a method that systematically characterizes the performance of a BESS. The method is sensitive enough to discern how changes in tuning parameters effect both grid service and the cycling of the BESS. This paper discusses the application of this methodology to a 1 MW BESS regulating the entire island of Hawaii (180 MW peak load) in-situ. Significant mitigation of renewable volatility was demonstrated while minimizing BESS cycling.
Particulate Matter Produced by Micro-Scale Biomass Combustion in an Oxygen-Lean Atmosphere
Authors: Poláčik Jan , Šnajdárek Ladislav , Špiláček Michal , Pospíšil Jiří , Sitek Tomáš
Published: December 2018

This article extends earlier research by the authors that was devoted to the experimental evaluation of ultra-fine particles produced by the laboratory combustion of beechwood samples. These particles can have severe influence on human health. The current paper presents a parametrical study carried out to assess the influence of the composition of the atmosphere and the temperature on the production of ultra-fine particles during the micro-scale combustion process. The paper presents a laboratory procedure that incorporate the thermogravimetric analysis (TGA) and detailed monitoring of the size distribution of the produced fine particles. The study utilises the laboratory scale identification of the formation and growth of the fine particles during the temperature increase of beech wood samples. It also compares the particle emissions produced by beech heartwood and beech bark. The size of the emitted particles is very strongly influenced by the concentration of light volatiles released from the heated wood sample. From the experimental study, decreasing oxygen content in the atmosphere generally results in higher particulate matter (PM) production.
Experimental Assessment of a Centralised Controller for High-RES Active Distribution Networks
Authors: García-López Francisco de Paula , Barragán-Villarejo Manuel , Marano-Marcolini Alejandro , Maza-Ortega José María , Martínez-Ramos José Luis
Published: December 2018

This paper assesses the behaviour of active distribution networks with high penetration of renewable energy sources when the control is performed in a centralised manner. The control assets are the on-load tap changers of transformers at the primary substation, the reactive power injections of the renewable energy sources, and the active and reactive power exchanged between adjacent feeders when they are interconnected through a DC link. A scaled-down distribution network is used as the testbed to emulate the behaviour of an active distribution system with massive penetration of renewable energy resources. The laboratory testbed involves hardware devices, real-time control, and communication infrastructure. Several key performance indices are adopted to assess the effects of the different control actions on the system’s operation. The experimental results demonstrate that the combination of control actions enables the optimal integration of a massive penetration of renewable energy.
Significance and Challenges of Biomass as a Suitable Feedstock for Bioenergy and Biochemical Production: A Review
Authors: Ahorsu Richard , Medina Francesc , Constantí Magda
Published: December 2018

Fossil fuels have been a major contributor to greenhouse gases, the amounts of which could be reduced if biofuels such as bioethanol and biodiesel were used for transportation. One of the most promising biofuels is ethyl alcohol. In 2015, the world production of ethanol was 25.6 billion gallons and the USA, Brazil, China, the European Union, and 28 other countries have set targets for blending ethanol with gasoline. The two major bio-source materials used for ethanol production are corn and sugarcane. For 1st generation biofuels, sugarcane and corn feedstocks are not able to fulfill the current demand for alcohol. Non-edible lignocellulosic biomass is an alternative bio-source for creating 2nd generation biofuels and algae biomass for 3rd and 4th generation biofuels. This review discusses the significance of biomass for the different generations of biofuels, and biochemical and thermochemical processes, and the significance of biorefinery products.
City Scale Demand Side Management in Three Different-Sized District Heating Systems
Authors: Kontu Kaisa , Vimpari Jussi , Penttinen Petri , Junnila Seppo
Published: December 2018

Demand side management can add flexibility to a district heating (DH) system by balancing the customer’s hourly fluctuating heat demand. The aim of this study is to analyze how different demand side management control strategies, implemented into different customer segments, impact DH production. A city scale heat demand model is constructed from the hourly heat consumption data of different customer segments. This model is used to build several demand side management scenarios to examine the effect of them on both, the heat producer, and the customers. The simulations are run for three different-sized DH systems, representing typical DH systems in Finland, in order to understand how the demand side management implementations affect the production. The findings imply that the demand side management strategy must be built individually for each specific DH system; the changing consumption profiles of different customer segments should be taken into consideration. The results show that the value of demand side management for a DH companies remains low (less than 2% in cost savings), having an effect mostly upon the medium loads without any significant decrease in annual peak heat loads. Also, the findings reflect that the DH pricing models should be developed to make demand side management more attractive to DH customers.
Stability Analysis in Determining Safety Drilling Fluid Pressure Windows in Ice Drilling Boreholes
Authors: Zhang Han , Pan Dongbin , Zhai Lianghao , Zhang Ying , Chen Chen
Published: December 2018

Borehole stability analysis has been well studied in oil and gas exploration when drilling through rock formations. However, a related analysis of ice borehole stability has never been conducted. This paper proposes an innovative method for estimating the drilling fluid pressure window for safe and sustainable ice drilling, which has never been put forward before. First, stress concentration on a vertical ice borehole wall was calculated, based on the common elastic theory. Then, three failure criteria, the Mogi–Coulomb, teardrop, and Derradji-Aouat criteria, were used to predict the stability of the ice borehole for an unbroken borehole wall. At the same time, fracture mechanics were used to analyze the stable critical pressure for a fissured wall. Combining with examples, our discussion shows how factors like temperature, strain rate, ice fracture toughness, ice friction coefficient, and fracture/crack length affect the stability of the borehole wall. The results indicate that the three failure criteria have similar critical pressures for unbroken borehole stability and that a fissured borehole could significantly decrease the safety drilling fluid pressure window and reduce the stability of the borehole. The proposed method enriches the theory of borehole stability and allows drillers to adjust the drilling fluid density validly in ice drilling engineering, for potential energy exploration in polar regions.
The Rebound Effect of Energy Efficiency Policy in the Presence of Energy Theft
Authors: Somuncu Tugba , Hannum Christopher
Published: December 2018

Introduction: Estimating the effectiveness of energy efficiency policy in reducing energy use requires a full understanding of the energy efficiency rebound effect, where energy use reductions differ from engineering expectations. Prior models that estimate the size of the total rebound effect ignore energy theft, which is a common feature in developing economies. Objectives: The primary objective of this study was to evaluate the role that energy theft plays in determination of the size of the rebound effect of energy efficiency policy in developing countries, using the Turkish economy and the specific Turkish regulation regarding compensation for energy theft as an example. Methods: We construct two energy-economy computable general equilibrium (CGE) models for Turkey that do and do not incorporate energy theft. Costs of energy theft are passed on to consumers through a recovery surcharge. Two energy efficiency policies are modeled; one leading to a 42% energy efficiency increment for the service sector and another leading to a 48% energy efficiency increment for households. Results: Without energy theft, rebound effects for both policies are small: between −1.4% and 3.1% for the service sector and between 0.4% and 2.1% for households. With energy theft, we see a −7.9% to −19.7% rebound for the service sector and a 10.4% to 40.7% rebound for households. The recovery surcharge on energy sales rises when energy efficiency gains affect the service sector but fall when they affect households. Conclusions: The interaction between energy efficiency and energy theft may be critical in accurate estimation of rebound effects where energy theft is prevalent. Where energy efficiency gains disproportionately reduce electricity sales rather than theft, the rising recovery surcharge leads to a negative rebound or super-conservation. However, where theft is disproportionately reduced rebound will be higher.