bluuebunny/crossref_metadata_2025 huggingface dataset:
Frac Sleeve Designed for Multi-Zone Cemented Laterals
Authors: Chauffe Steve , Pence Nigel , Harris Michael
Published: April 2015

A ball-activated sliding sleeve design for multistage cemented lateral completions has been developed that allows multiple frac sleeves to be opened using the same diameter ball, significantly increasing the total number of sleeves available in the completion design. This paper discusses the sleeve design, the challenges associated with cemented laterals, the results of initial field installations, and the ramifications for completion design and execution.

Ball-activated sleeves were introduced to overcome limitations of plug and perf designs and facilitate longer and more complex completions. As these completions have evolved, the technology has reached inherent design limitations. This is especially true in cemented lateral completions. These installations require a series of incrementally smaller balls and ball seats that reduce wellbore ID and ultimately limit the total number of sleeves that can be used in the completion.

To further extend lateral length and accommodate the cemented laterals, a sliding sleeve device has been developed that allows multiple sliding sleeve valves to be opened with the same size ball and seat. The sliding sleeve design allows up to 90 individual sleeves to be opened as a single point of entry completion without dropping a ball diameter smaller than 4.00-in. in 5.500-in. casing, or a 3.25-in. ball in 4.500-in. casing. This increases wellbore ID over the length of the completion, and increases the total number of sleeves or sleeve clusters that can be employed in the completion design. The higher number of available sleeves affects the completion design, whether it uses single sleeve per stage or clusters of sleeves. In addition, lateral length of the completion is not constrained by the number of sleeves or the reach of coiled tubing.

Cemented installations in the US Marcellus, Utica Shale, and Spraberry plays have enabled single-point-of-entry stimulations that optimize hydraulic fracturing pressure and provide a focused frac. In some applications, this has reduced pump rates and surface horsepower requirements by as much as 50% and also reduced the overall frac time. Experience also indicates these completions reduce water requirements by minimizing over-flushing of the formation. These cemented installations illustrate the potential of continued changes in completion designs and the viability of longer laterals.

This paper is the first published examination of field performance in the initial installations of the sliding sleeve technology. Field results and data from sleeves installed in Marcellus, Utica Shale, and Spraberry completions are presented. Based on performance in these applications, the paper reviews completion design considerations facilitated by the ability to install larger numbers of sliding sleeves over longer cemented laterals.
Boundary Conditions: A Key Factor in Tubular-String Buckling
Authors: Huang Wenjun , Gao Deli , Wei Shaolei , Chen Pengju
Published: April 2015

Boundary conditions for tubular-string buckling are divided into two kinds on the basis of the virtual work of the nonaxial force on the boundary conditions of the tubular string—namely, the first and the second kinds of boundary conditions. The first kind of boundary conditions means that the virtual work of no-axial force is zero, and both the conventional pinned and fixed ends belong to this kind. The second kind of boundary conditions means that the virtual work of no-axial force is not zero. Previous studies on tubular-string buckling mainly focus on the first kind but ignore the second kind of boundary conditions. In this paper, the effects of the two kinds of boundary conditions on tubular-string buckling are analyzed.

The deflection of a long tubular string constrained in a wellbore is divided into the full helical-buckling section and transition section, whereas the transition section is divided further into the no-contact section and perturbed-helix section. The qualitative corresponding relation between boundary conditions and tubular-string buckling in transition and full helical-buckling sections is clarified. To clarify the quantitative relation between boundary conditions and tubular-string buckling, a general-packer model is proposed to depict the two categories of boundary conditions. With the general-packer model, the general potential energy of the tubular string is deduced. According to the minimum-potential-energy principle, the existence and stability of full helical-buckling solutions are given. The deflections of the tubular string in the no-contact and perturbed-helix sections are deduced with buckling differential equation and beam-column model. The bending moment, shear force, and contact force on the tubular string caused by buckling are also analyzed. The results show that boundary conditions, especially the second kind of boundary conditions, are an important factor that makes the tubular-string buckling problem complex, and this paper provides one source for a deeper understanding of boundary conditions.
Short Radius Horizontal Drilling System Optimization in Yates Field Unit Provides Excellent Directional Control and Highly Economic Completions
Authors: Tank W. J.
Published: April 2015

Yates Field Unit in Pecos County, Texas, has recently drilled its 100th short radius horizontal drainhole. The program has been a technical as well as economic success for the field, providing efficient completions in this highly fractured reservoir.

In the early stages of the program (1986 – 1990), short radius drilling in Yates Field Unit was performed using strictly rotary drilling systems. In 1992, Odorisio and Curtis1 reported on the introduction of articulated downhole mud motors to the program and the impact of the initial modifications to the system. Since that time over 75 additional drainholes have been drilled. Two other drilling systems have been tested and many improvements have been made to the original system. This paper documents the optimization that has occurred in the drilling systems and results obtained from this work.
Acquired cystic disease and renal cell carcinoma in hemodialysis patients: A case report on three patients
Authors: Mijuskovic Mirjana , Milovic Novak , Kovacevic Bozidar , Jovanovic Dragan , Stefanovic Dara , Ignjatovic Ljiljana , Terzic Brankica , Tadic-Pilcevic Jelena , Petrovic Marijana , Pilcevic Dejan , Obrencevic Katarina , Cerovic Snezana
Published: April 2015

Introduction. Renal cell carcinoma (RCC) is derived from renal tubular
epithelial cells and represents approximately 3.8% of all malignancies in
adults. The incidence of renal cell carcinoma has been growing steadily and
ranging from 0.6 to 14.7 for every 100,000 inhabitants. Patients with
end-stage renal disease and acquired cystic kidney disease are at increased
risk of developing RCC while undergoing dialysis treatment or after renal
transplantation. Case report. We presented 3 patients undergoing
hemodialysis, with acquired cystic kidney disease accompanied by the
development of RCC. In all the patients tumor was asymptomatic and discovered
through ultrasound screening in 2 patients and in 1 of the patients by
post-surgery pathohistological analysis of the tissue of the kidney excised
using nephrectomy. All the three patients had organ-limited disease at the
time of the diagnosis and they did not require additional therapy after
surgical treatment. During the follow- up after nephrectomy from 6 months to
7 years, local recurrence or metastasis of RCC were not diagnosed.
Conclusion. Acquired cystic kidney disease represents a predisposing factor
for the development of renal cell carcinoma in dialysis patients and requires
regular ultrasound examinations of the abdomen aimed at early diagnosis of
malignancies. Prognosis for patients with endstage renal disease and RCC is
mostly good because these tumors are usually of indolent course.
Giant primary retroperitoneal seminoma: A case report
Authors: Jovanovic Milan , Janjusevic Natasa , Mirkovic Darko , Vulovic Maja , Milev Bosko , Mitrovic Miroslav , Trifunovic Bratislav
Published: April 2015

Introduction. Primary extragonadal seminomas are rare tumors. There have been
only a few cases of the primary retroperitoneal seminomas reported in the
literature up to date. Case report. We reported a 56-year-old man with giant
primary retroperitoneal seminoma presented with the enlargement of the left
side of the abdomen and deep venous thrombosis of the left leg. Computed
tomography of the abdomen showed a large tumor occupying the left part of the
retroperitoneal space with 23 x 13 cm in diameter. Firm tumor mass having 25
x 15 cm in diameter was surgically removed from the left retroperitoneum. The
tumor adhered the tunica adventitia of the aorta and it was carefully
resected from the aortic wall. The diagnosis of seminoma was made during
histopathological examination. The patient underwent chemotherapy. Two years
after finished chemotherapy the patient accepted left orchiectomy with the
aim of eliminating the possibility of the occult malignancy of the testicle.
Histopathological analysis of the testicular tissue was normal and the
diagnosis of primary retroperitoneal seminoma was confirmed. Conclusion.
Despite its small incidence in general population, the diagnosis of
retroperitoneal seminoma should be considered in male patients with
nonspecific symptoms and with retroperitoneal tumor mass.
A Two Layered Control Architecture for Prosthetic Grasping
Authors: Kakoty Nayan M. , Hazarika Shyamanta M.
Published: April 2015

This paper presents a two layered control architecture - Superior hand control (SHC) followed by Local hand control (LHC) for an extreme upper limb prosthesis. The control architecture is for executing grasping operations involved in 70% of daily living activities. Forearm electromyogram actuated SHC is for recognition of user’s intended grasp. LHC control the fingers to be actuated for the recognized grasp. The finger actuation is controlled through a proportionalintegral- derivative controller customized with fingertip force sensor. LHC controls joint angles and velocities of the fingers in the prosthetic hand. Fingers in the prosthetic hand emulate the dynamic constraints of human hand fingers. The joint angle trajectories and velocity profiles of the prosthetic hand finger are in close approximation to those of the human finger
Towards Measuring Quality of Interaction in Mobile Robotic Telepresence using Sociometric Badges
Authors: Kristoffersson Annica , Coradeschi Silvia , Eklundh Kerstin Severinson , Loutfi Amy
Published: April 2015

The field of mobile robotic telepresence for social communication is in rapid expansion and it is of interest to understand what promotes good interaction. In this paper, we present the results of an experiment where novice users working in health care were given a guided tour while maneuvering a mobile robotic telepresence system for the first time. In a previous study, it was found that subjective presence questionnaires and observations of spatial configurations based on Kendon’s F-formations were useful to evaluate quality of interaction in mobile robotic telepresence. In an effort to find more automated methods to assess the quality of interaction, the study in this paper used the same measures, with the addition of objective sociometric measures. Experimental results show that the quantitative analysis of the sociometric data correlates with a number of parameters gathered via qualitative analysis, e.g. different dimensions of presence and observed problems in maneuvering the robot.
Cooking Behavior with Handling General Cooking Tools based on a System Integration for a Life-sized Humanoid Robot
Authors: Watanabe Yoshiaki , Nagahama Kotaro , Yamazaki Kimitoshi , Okada Kei , Inaba Masayuki
Published: April 2015

This paper describes a system integration for a life-sized robot working at a kitchen. On cooking tasks, there should be various tools and foods, and cooking table may have reflective surface with blots and scratch. Recognition functions should be robust to noises derived from them. As other problems, cooking behaviors impose motion sequences by using whole body of the robot. For instance, while cutting a vegetable, the robot has to hold one hand against the vegetable even if another hand with a knife should be moved for the cutting. This motion requires to consider full articulation of the robot simultaneously. That is, we have difficulties against both recognition and motion generation. In this paper we propose recognition functions that are to detect kitchen tools such as containers and cutting boards. These functions are improved to overcome the influence of reflective surface, and combination shape model with task knowledge is also proposed. On the other hand, we pointed out the importance of the use of torso joints while dual arm manipulation. Our approach enables the robot to keep manipulability of both arms and viewing field of a head. Based on these products, we also introduce an integrated system incorporating recognition modules and motion generation modules. The effectiveness of the system was proven through some cooking applications.
A Distributed Algorithm for Cooperative 3D Exploration under Communication Constraints
Authors: Rathnam Ravi Kulan , Birk Andreas
Published: April 2015

An algorithm for distributed exploration in 3D is presented which always keeps the robots within communication range of each other. The method is based on a greedy optimization strategy that uses a heuristic utility function. This makes it computationally very efficient but it can also lead to local minimums; but related deadlocks can be easily detected during the exploration process and there is an efficient strategy to recover from them. The exploration algorithm is integrated into a complete control infrastructure for Autonomous Underwater Vehicles (AUV) containing sensors, mapping, navigation, and control of actuators. The algorithm is tested in a high fidelity simulator which takes into account the dynamics of the robot, and simulates the required sensors. The effect of the communication range and the number of robots on the algorithm is investigated.
Multiattribute Utility Copulas for Multi-objective Coverage Control
Authors: Valicka Christopher G. , Rekoske Richard A. , Stipanovic Dušan M. , Abbas Ali E.
Published: April 2015

This paper presents theoretical and experimental results related to the control and coordination of multirobot systems interested in dynamically covering a compact domain while remaining proximal, so as to promote robust inter-robot communications, and while remaining collision free with respect to each other and static obstacles. A design for a novel, gradient-based controller using nonnegative definite objective functions and an overapproximation to the maximum function is presented. By using a multiattribute utility copula to scalarize the multiobjective control problem, a control law is presented that allows for flexible tuning of the tradeofs between objectives. This procedure mitigates the controller’s dependence on objective function parameters and allows for the straightforward integration of a novel global coverage objective. Simulation and experiments demonstrate the controller’s efectiveness in promoting scenarios with collision free trajectories, robust communications, and satisfactory coverage of the entire coverage domain concurrently for a group of differential drive robots.
Coded access optical sensor (CAOS) imager
Authors: Riza N. A. , Amin M. J. , La Torre J. P.
Published: April 2015

High spatial resolution, low inter-pixel crosstalk, high signal-to-noise ratio (SNR), adequate application dependent speed, economical and energy efficient design are common goals sought after for optical image sensors. In optical microscopy, overcoming the diffraction limit in spatial resolution has been achieved using materials chemistry, optimal wavelengths, precision optics and nanomotion-mechanics for pixel-by-pixel scanning. Imagers based on pixelated imaging devices such as CCD/CMOS sensors avoid pixel-by-pixel scanning as all sensor pixels operate in parallel, but these imagers are fundamentally limited by inter-pixel crosstalk, in particular with interspersed bright and dim light zones. In this paper, we propose an agile pixel imager sensor design platform called Coded Access Optical Sensor (CAOS) that can greatly alleviate the mentioned fundamental limitations, empowering smart optical imaging for particular environments. Specifically, this novel CAOS imager engages an application dependent electronically programmable agile pixel platform using hybrid space-time-frequency coded multiple-access of the sampled optical irradiance map. We demonstrate the foundational working principles of the first experimental electronically programmable CAOS imager using hybrid time-frequency multiple access sampling of a known high contrast laser beam irradiance test map, with the CAOS instrument based on a Texas Instruments (TI) Digital Micromirror Device (DMD). This CAOS instrument provides imaging data that exhibits 77 dB electrical SNR and the measured laser beam image irradiance specifications closely match (i.e., within 0.75% error) the laser manufacturer provided beam image irradiance radius numbers. The proposed CAOS imager can be deployed in many scientific and non-scientific applications where pixel agility via electronic programmability can pull out desired features in an irradiance map subject to the CAOS imaging operation.
Conservation agriculture options for a Rice-Maize cropping systems in Bangladesh
Authors: Islam AKM Saiful , Hossain MM , Saleque MA
Published: April 2015

Over the last two decades, Rice (Oryza sativa L.)-Maize (Zea mays L.) cropping systems have become one of the most dominant cropping systems in Bangladesh. This has coincided with the expansion in use of two-wheel tractors, which has facilitated options for minimum tillage. A three-year trial examined the prospects of conservation agriculture practices for Rice-Maize cropping in Bangladesh, with respect to minimum tillage and residue retention. Main plot tillage treatments of conventional full tillage, single pass wet tillage in rice (rotated with zero tillage in maize), bed planting and strip tillage were combined with residue retention treatments of 0, 50 and 100% in sub-plots. Compared to conventional tillage, minimum tillage saved 60-66% of fuel and 70-74% of labour required for land preparation. Although minimum tillage reduced the land preparation cost significantly through saving fuel and labour, weed infestation was higher compared to conventional tillage, which influenced the cost of production. Rice seedlings transplanted under unpuddled strip tillage required more time than in conventional or single pass wet tillage due to poor visibility of strips and the hard surface of untilled soil. Bed planting incurred the lowest production cost. Tillage methods and residue treatment produced no significant grain yield differences. Rice grown with single pass wet tillage and maize grown with strip tillage gave the highest gross margin over time. Despite lack of treatment effects on yields, the results suggest that profitability of Rice-Maize cropping could be increased with minimum tillage, provided there is adequate control of weeds by herbicides.Bangladesh Rice j. 2014, 18(1&2): 44-53
Establishing a Clinic-Based Pancreatic Cancer and Periampullary Tumour Research Registry in Quebec
Authors: Smith A.L. , Bascuñana C. , Hall A. , Salman A. , Andrei A.Z. , Volenik A. , Rothenmund H. , Ferland D. , Lamoussenery D. , Kamath A.S. , Amre R. , Caglar D. , Gao Z.H. , Haegert D.G. , Kanber Y. , Michel R.P. , Omeroglu–Altinel G. , Asselah J. , Bouganim N. , Kavan P. , Arena G. , Barkun J. , Chaudhury P. , Gallinger S. , Foulkes W.D. , Omeroglu A. , Metrakos P. , Zogopoulos G.
Published: April 2015

Background: Enrolling patients in studies of pancreatic ductal adenocarcinoma (pdac) is challenging because of the high fatality of the disease. We hypothesized that a prospective clinic-based study with rapid ascertainment would result in high participation rates. Using that strategy, we established the Quebec Pancreas Cancer Study (qpcs) to investigate the genetics and causes of pdac and other periampullary tumours (pats) that are also rare and underrepresented in research studies. Methods: Patients diagnosed with pdac or pat were introduced to the study at their initial clinical encounter, with a strategy to enrol participants within 2 weeks of diagnosis. Patient self-referrals and referrals of unaffected individuals with an increased risk of pdac were also accepted. Family histories, epidemiologic and clinical data, and biospecimens were collected. Additional relatives were enrolled in families at increased genetic risk. Results: The first 346 completed referrals led to 306 probands being enrolled, including 190 probands affected with pdac, who represent the population focus of the qpcs. Participation rates were 88.4% for all referrals and 89.2% for pdac referrals. Family history, epidemiologic and clinical data, and biospecimens were ascertained from 91.9%, 54.6%, and 97.5% respectively of patients with pdac. Although demographics and trends in risk factors in our patients were consistent with published statistics for patients with pdac, the qpcs is enriched for families with French-Canadian ancestry (37.4%), a population with recurrent germ-line mutations in hereditary diseases. Conclusions: Using rapid ascertainment, a pdac and pat research registry with high participation rates can be established. The qpcs is a valuable research resource and its enrichment with patients of French-Canadian ancestry provides a unique opportunity for studies of heredity in these diseases.
Canadian Consensus Recommendations on the Management of Venous Thromboembolism in Patients with Cancer. Part 1: Prophylaxis
Authors: Easaw J.C. , Shea–Budgell M.A. , Wu C.M.J. , Czaykowski P.M. , Kassis J. , Kuehl B. , Lim H.J. , MacNeil M. , Martinusen D. , McFarlane P.A. , Meek E. , Moodley O. , Shivakumar S. , Tagalakis V. , Welch S. , Kavan P.
Published: April 2015

Patients with cancer are at increased risk of venous thromboembolism (vte). Anticoagulation therapy has been shown to prevent vte; however, unique clinical circumstances in patients with cancer can often complicate the decisions surrounding the administration of prophylactic anticoagulation. No national Canadian guidelines on the prevention of cancer-associated thrombosis have been published. We therefore aimed to develop a consensus-based, evidence-informed guideline on the topic. PubMed was searched for clinical trials and meta-analyses published between 2002 and 2013. Reference lists of key articles were hand-searched for additional publications. Content experts from across Canada were assembled to review the evidence and make recommendations. Low molecular weight heparin can be used prophylactically in cancer patients at high risk of developing vte. Direct oral anticoagulants are not recommended for vte prophylaxis at this time. Specific clinical scenarios, including renal insufficiency, thrombocytopenia, liver disease, and obesity can warrant modifications in the administration of prophylactic anticoagulant therapy. There is no evidence to support the monitoring of anti–factor Xa levels in clinically stable cancer patients receiving prophylactic anticoagulation; however, factor Xa levels could be checked at baseline and periodically in patients with renal insufficiency. The use of anticoagulation therapy to prolong survival in cancer patients without the presence of risk factors for vte is not recommended.
Preference of e-Bike by Women in India–a Niche Market for Auto Manufacturers
Authors: Alamelu Ramachandran , Anushan Chandrasekaran Sivasundaram , Selvabaskar Sivasankara Gandhi
Published: April 2015

The increasing urbanization with climate change, global warming issues and the related need to decarbonize the economy, is forcing urgency for identifying the alternate source for the global adoption and sustainable scalable solutions. The country’s demographic and road patterns and its natural resources availability provide enormous scope for the electric bike industry. As per the “Navigant Research Report”, it is predicted that by 2018, the sales of electric vehicles in India will shoot up by 17 percent. 1.1 million electric vehicles will be targeted within next five years. A recent study on the environment impact of e-bikes with other forms of transportation found that e-bikes are about 18 times more energy consumption than SUV, 13 times than a sedan, 6 times more than rail transit, and it is having considered as an innovated conventional bicycle. It is a frugal innovation strategy which provide safe carbon free environment, and moreover a part of health rehabilitation programmes. It is required that societal, economic and political and infrastructure systems integrate together to balance the energy environment. With this potential, the era of electric bike started its new avenues on the roads of India specifically focusing on Indian women. To develop this viewpoint, the present study focuses on the preference of e-bike among the women in Madurai city.
Epigenetics and Evolution: Transposons and the Stochastic Epigenetic Modification Model
Authors: Branciamore Sergio , Rodin Andrei S. , Gogoshin Grigoriy , Riggs Arthur D.
Published: April 2015

In addition to genetic variation, epigenetic variation and transposons can greatly affect the evolutionary fitnesses landscape and gene expression. Previously we proposed a mathematical treatment of a general epigenetic variation model that we called Stochastic Epigenetic Modification (SEM) model. In this study we follow up with a special case, the Transposon Silencing Model (TSM), with, once again, emphasis on quantitative treatment. We have investigated the evolutionary effects of epigenetic changes due to transposon (T) insertions; in particular, we have considered a typical gene locus A and postulated that (i) the expression level of gene A depends on the epigenetic state (active or inactive) of a cis-located transposon element T, (ii) stochastic variability in the epigenetic silencing of T occurs only in a short window of opportunity during development, (iii) the epigenetic state is then stable during further development, and (iv) the epigenetic memory is fully reset at each generation. We develop the model using two complementary approaches: a standard analytical population genetics framework (diffusion equations) and Monte-Carlo simulations. Both approaches led to similar estimates for the probability of fixation and time of fixation of locus TA with initial frequency P in a randomly mating diploid population of effective size Ne
. We have ascertained the effect that ρ, the probability of transposon modification during the developmental window, has on the population (species). One of our principal conclusions is that as ρ increases, the pattern of fixation of the combined TA locus goes from “neutral” to “dominant” to “over-dominant”. We observe that, under realistic values of ρ, epigenetic modifications can provide an efficient mechanism for more rapid fixation of transposons and cis-located gene alleles. The results obtained suggest that epigenetic silencing, even if strictly transient (being reset at each generation), can still have significant macro-evolutionary effects. Importantly, this conclusion also holds for the static fitness landscape. To the best of our knowledge, no previous analytical modeling has treated stochastic epigenetic changes during a window of opportunity.
Thermo-Mechanical Behavior of the Shape Memory Alloy Strip
Authors: Zhao Peng Tao , Qiu Jin Hao , Yu Hui Chen
Published: April 2015

As a new type of smart material, shape memory alloy (SMA) is widely used in the aerospace, biomedicine, civil engineering and so on due to its unique mechanical and physical properties such like the shape memory effect, pseudoelasticity and good biological compatibility. This paper investigates the numerical simulation and application of the SMA component: A SMA strip, which has been pre-curved in the room temperature and is expected to extend upon heating and shorten on cooling along the curve. According to the investigation of the thermal respond of the SMA strip component, it can be seen that the temperature of the phase transformation can increase with the initial transformation strains and the process of the phase transformation in the boundary is more complex due to the complicated stress state.
Numerical Simulation on Fatigue Life Assessment of Free Span for Submarine Pipeline
Authors: Dong Jie , Chen Xue Dong , Wang Bing , Guan Wei He , Yang Tie Cheng , Fan Zhi Chao , Pan Jian Hua
Published: April 2015

The upper and lower courses of sea oil and gas exploitationare connected by submarine pipeline which is called life line project. Free span often occurs because of the unevenness and scour of seabed, and fatigue is one of the main failure modes.In this paper, with the finite element numerical simulation method, based on the harmonic response analysis, the research on the structural response of free span under the vibration induced by vortex was investigated, and the effect of the factors such as flow velocity, length of free span. According to the analysis results,the fatigue life of free span was evaluated.
The Effect of Two Wire Submerge Welding Parameters on the Properties of Welded Joint
Authors: Ma Chun Wei , Liu Ting Yu , Tang Yan Yan , Lu Qing Hua , Li Chong Gui , Yan Hua
Published: April 2015

In this paper, the influence of double wire submerged arc welding parameters on the mechanical properties of high strength low alloy has been investigated. The 20mm steel plate has been welded by double wire submerged arc welding process using different welding parameters. The Charpy absorbed energy of specimens is assessed using impact test at the temperature of -50°C. Testing results show that high heat input parameters will lead to low strength of welded joint. Impact toughness of fusion line is lower than that of other areas of welded joint.
Effect of Coking Size on the Thermal Diffusion and Stress Distribution of Cr25Ni35Nb and Cr35Ni45Nb Austenitic Steels
Authors: Shen Li Min , Gong Jian Ming , Liu Huan Sheng
Published: April 2015

Cr25Ni35Nb and Cr35Ni45Nb austenitic steels, used as furnace tube material in the ethylene pyrolysis furnace, generally suffer from coking during the long operation period. In the present paper, for coked Cr25Ni35Nb and Cr35Ni45Nb austenitic steel, using the finite element ABAQUS code, a sequentially coupled thermal stress procedure was developed to calculate distribution of the temperature and thermal stress field. The results show that thermal diffusion property of Cr25Ni35Nb and Cr35Ni45Nb steel deteriorates obviously with coking layer increasing. Radial bulge and rupture at local field would generate due to excess temperature for applied subsequent measurement. Maximum stress distribute along the cross-section of coking layer and metal matrix. Finally, the critical depth of coking layer of Cr25Ni35Nb and Cr35Ni45Nb austenitic steel are predicted when decoking measurement must be executed.
Limit Load Analysis of Elbow with Local Wall Thinning under Combined Loads
Authors: Cui Peng , Zhou Chang Yu
Published: April 2015

The local wall thinning(LWT) is a kind of common volume defect in pressure pipe. The limit loads of elbows with LWT under pressure, bending moment, torque and their combined loads have been studied in detail by orthogonal experimental design and finite element method. The results have shown that the influence of depth and circumferential length of LWT on the limit load is more obvious compared to that of axial length when an elbow is under pressure, bending moment or torque. The change of limit bending moment and torque with the depth of LWT and circumferential length is significant for an elbow under combined bending moment and torque. At last, the safety assessment equations for elbow under combined in-plane closing bending moment and torque were proposed by regression analysis.
Measurement of Welding Residual Stress by Ultrasonic Technology
Authors: Chen Hu , Zhu Jin Dan , Xiang Yan Xun
Published: April 2015

An ultrasonic method was developed to measure the residual stress in a welded joint based on the modified acoustic-elasticity theory. Phase frequency analysis method was introduced by incombination with shear wave and longitudinal wave. The acoustic-elasticity parameters of joint material was derived by ultrasonic inspection during loading experiment. Transverse and longitudinal residual stress was determined by precisely measuring of short-distance acoustic travel time. The ultrasonic measurement results was confirmed by H&K theory and XRD methods with good repeatability and reliability.
Contact Nonlinear FE Analysis and Intensity Evaluation of Double-Cone Seal
Authors: Wang He Hui , Yang Ran Xia , Lu Jun Chen
Published: April 2015

In the paper double-cone seal of ammonia converter is analyzed by means of the finite element method. The contact nonlinear FEM is adopted to simulate the process of double-cone seal in the pretension condition and the operation condition. The curve of contact stress versus time is generated based on the simulation. The stress distribution of plat head and seal ring identified that the standard radial clearance design in GB150-2011 is reasonable and can meet the seal requirements. The deformation and stress distribution evaluation of the entire double-cone seal is further conducted. Bolts load obtained from analysis result and theoretical value of the two conditions are in good agreement, and the deviation is less than 2.1%, which proves that the simulation result is reliable.
Simulation of Turbulent Heat Transfer in a Tube Fitted with Twisted Tape Placed Separately from the Tube Walls
Authors: Piriyarungroj Niwat , Eiamsa-ard Smith , Promvonge Pongjet , Eiamsa-Ard Petpices , Thianpong Chinaruk
Published: April 2015

The effects of loose-fit twisted tape (LFT) on the heat transfer rate, friction factor, fluid phenomena and thermal performance of a tube under constant wall temperature are examined. It is observed that apart from the rise of Reynolds number, the reduction of the clearance ratio (c/D) leads to an increase in the heat transfer and pressure loss. According to the numerical results, the heat transfer and friction factor in the tubes with loose-fit twisted tape (LFT) for the smallest clearance ratio of c/D = 0.05 are higher those other clearance ratios. In addition, the thermal performances of clearance ratio c/D = 0.05 are found to be higher than those other clearance ratios (c/D) for all Reynolds numbers examined.
The Design and Implementation of Food Cold Chain Monitoring System Based on ZigBee
Authors: Wu Mei Mei
Published: April 2015

The article mainly introduced the design and implementation of food cold chain monitoring system, Introduces the realization method of ZigBee, GPS, GPRS, GIS, embedded system and remote database and remote access technology based on the network, Realized the environment real-time monitoring and real-time location information records to the cold chain transportation of refrigerator truck, and can access it from the remote network.
Influence of Mongolian Iron Concentrate Proportion on Roasting Characteristics
Authors: Guo Zhuo Tuan , An Sheng Li , Wu Di , Peng Jun , Wang Yi Ci
Published: April 2015

Mongolia ore is introduced in order to reduce pellet production costs in Baotou steel because of the increasing prices of iron concentrate year by year. But the production experience for pellets containing Mongolian ore is in short, and the basic characteristics of the pellets need to be analyzed. Previous analysis show that the particle size of Mongolia concentrate is relatively small, which could not be used alone but could be used with coarse grain size home-made concentrate [1,2]. The ballability index of Mongolia ore concentrate is 0.35. The Crystal stock characteristics of Mongolia mine is poor, which lead to the average strength of the pellets drop to 942.7N. With home-made concentrate mixed with Mongolian mine ratio increases, the intensity of the crystal stock also shows a downward trend, while the ratio more than 65% of Mongolia mine later, even crystal stock level dropped significantly.
Mn2+ and Co2+ Removal from Dilute Solution Using Cysteine Grafted Cobalt/Manganese Imprinted Crosslinked Chitosan
Authors: Liu Fa Bang , Jia Ming Chun , Men Jin Feng , Wang Xiao Wei
Published: April 2015

Several kinds of spherical cysteine grafted cobalt/manganese imprinted crosslinking chitosan spheres were synthesized for Mn2+ and Co2+ removal, in which Mn2+ and Co2+ were used separately or together as imprinting ions. Structures of the adsorbents were analyzed utilizing the techniques of SEM and FTIR. The effects of initial pH, contact time, presence of other cations, initial Mn2+ and Co2+ concentration on adsorption were investigated. Furthermore, adsorption kinetics and isotherm were studied, which showed sorption data fitted to pseudo-second-order and Langmuir models for both Mn2+ and Co2+. The overall results indicated the possibility of using Cys–Co/Mn–CCTS–2 for efficient removal of Mn2+ and Co2+ from dilute low-level radioactive liquid waste.
Effect of Heat Treatment on the Microstructure of Duplex Stainless Steel
Authors: Nachazel Jan , Martínek Petr , Podany Pavel , Polakova Ivana
Published: April 2015

The aim of this paper is to research the influence of a different heat treatment of duplex austenitic-ferritic stainless steel to a microstructure. First, the initial data for numerical simulation were obtained by tensile test. Numerical simulation serves to determine the state of the workpiece during open die forging. The second stage focused on the evaluation of the microstructure in state after dwell time at forging temperature (7-and 10-hour) and cooling (water, air). Metallographic analysis observed the influence on precipitation of secondary phase especially.
Development of Foot Modules of an Exoskeleton Equipped with Multiple Sensors for Detecting Walking Phase and Intent
Authors: Son Byoung Jong , Baek Yoon Su , Kim Jung Hoon
Published: April 2015

This paper presents design and application of foot modules in exoskeleton. Detecting the walking phase and intent is most important data for controlling the wearable exoskeleton. The zero moment point (ZMP) trajectory in the robot foot support area is significant criterion for a stability of the walk. The ZMP is calculated by measured force / torque data and Force / Torque sensor (F/T sensor) can measure that. But, the thick foot module is inconvenient to walking. For such a reason, most foot modules are developed using the film type sensors such as force sensing resistor (FSR), ground contact sensor such as tape switch and so on. In this paper, the foot modules equipped optimal design of 3-axis F/T sensor and ground contact sensor are presented and experimental application of detecting the walking phase using both sensors is introduced.
Development of Exoskeleton 4-Bar Linkage Gripper for Front End Module (FEM) Assembly Process
Authors: Shim Myoung Hoon , Kim Jung Hoon
Published: April 2015

In this paper, development of exoskeleton gripper targeted for FEM assembly process is described. This exoskeleton system is currently being under study for industry field application. The proposed gripper system is capable of robustly connecting bulky heavy-weighted FEM to exoskeleton robot system. In order to reduce the load on the exoskeleton, lightening method based on H-beam structure is used alongside with the usage of small actuators which was possible due to 4-bar linkage. Finally, performance of the developed gripper was validated through experiments.
Computational Study of Bone Tissue Mechanical Properties Dependence on Nanoscale Morphological Characteristics
Authors: Semenov A.S. , Grishchenko Alexey I. , Melnikov Boris E.
Published: April 2015

A bone tissue is modeled at the nanolevel as a composite with a quasiperiodic structure, consisting of the hydroxyapatite crystals, which are embedded into the collagen fibrils. The aim of the research is to analyze the influence of the bone nanostructure on its mechanical and strength properties. Such studies are important for the creating artificial bone-substitute materials. The influence analysis of the morphological characteristics (hydroxyapatite crystals disorientation, sizes and orientation of mineral bridges, shape of hydroxyapatite crystals, mineralization) on the local stress-strain state and mechanical properties of the representative volume element of bone is carried out by means of the direct finite element simulation and homogenization. The comparison of the obtained results with experimental data demonstrates a good agreement.
Employee Attendance Checker in Manufacturing Using Barcode and Mobile with Embedded Camera
Authors: Subpratatsavee Puchong , Kongtrakul Tanapas
Published: April 2015

In Thailand Manufacturing, checking employee attendance is one of the important issues for human resource, because many manufacturing evaluate employees’ attendance and while giving the final bonus, HRs considers their total number of appearances on manufacture during the whole work time. This brings to the idea of having some tool to control employees’ attendance. Some manufacturing prefer to use paper sheet for controlling attendance, whereas some manufacturing prefer to use paper sheet for checking employees' attendance and after this, fill out these information into a system manually, like Thailand Manufacturing in Siracha Province does. However, this is not an efficient way since there will be spent much of time for checking employees names and putting marks like "presence" or "absence". Moreover, some employees may call his/her friend as "presence" even though this employee is currently absent. After thinking all these issues, researcher of the following research paper decided to create a system that makes easier to check employees’ attendance automatically, and this system is implemented in Thailand Manufacturing near SiRacha province. Actually, this is the first time when such kind of system is being used in manufacturing system of Thailand. The system is based on 1D barcode technology and run on mobile application with Android OS, and in this paper, details of this system are presented.
3D Mosaic from Images
Authors: Park Ji Hun
Published: April 2015

This paper presents a tool for 3D object mosaic. Given a set of background removed input images, we first compute a 3D reconstructed volumetric model body using shape from silhouette. The granularity of a volumetric body is the user input. Voxel center coordinates, voxel color, and surface normal of the voxel are computed for 3D mosaic. The voxels of reconstructed volumetric body are replaced by primitive shapes such as sphere, cylinder, cone, etc. We call this process as a 3D mosaic. The background-eliminated input images may contain information on body parts supplied by a user.
Using information on body parts, only a part of 3D reconstructed volumetric body is replaced by a new shape while the rest of body retains voxel information. The surface normal values are used for primitive shapes with direction such as a cone. 3D mosaic can be used for emphasizing or deemphasizing a part of 3D reconstructed model body, similar to the function of a 2D image mosaic. Emphasizing and deemphasizing is done by resolution, surface normal, size of body parts, color and/or shape of the 3D primitive object.
Sintering Behavior and Microstructure Character of Magnesia Partially Stabilized Zirconia Ceramics
Authors: Jiang Lan , Guo Shu Qiang , Bian Yu Yang , Chen Song , Xu Yu Ling , Liu Yin He , Ding Wei Zhong
Published: April 2015

Commercial magnesia partially stabilized zirconia (MgO-PSZ) has been selected as the starting materials. Different sintering temperatures have been investigated to determine the optimal conditions. The sintering behavior and characteristic of MgO-PSZ are investigated in this work. Microstructures have been obviously affected by different sintering temperatures. According to dilatometer curve, sintering curve and the shrinkage ratio of sintering process have been estimated. The obtained microstructures have been characterized by scanning electron microscope (SEM).
Effective Extraction of State Invariant for Software Verification
Authors: Chun Seung Su
Published: April 2015

In software design of complex systems, more time and effort are spent on verification than on constructions. Model checking for software verification techniques offer a large potential to obtain and early integration of verification in the design process. This paper describes how to easily specify and the software properties and to understand the software generating automatically invariant. In this paper deal with issue that state invariant is a property that holds in every reachable state. Not only can be used in understanding and analysis of complex software systems. In addition, it can be used for system verifications such as checking safety, consistency, and completeness.
For these reasons, there are many vital researches for deriving state invariant from finite state machine models. In this research was to be considered to extract state invariant. Thus it is likely to be too complex for the user to understand. This paper let the user focus on some interested parts (called scopes) rather than a whole state space in a model. Computation Tree Logic (CTL) is used to specify scopes in which he/she is interested. Given a scope in CTL, forward reachability analysis is used to find out a set of states inside it. Obviously, a set of states calculated in this way is a subset of every reachable state.
Keywords: Software verification, Invariant, Scopes, Model Checking
Hybrid Distributed Correlation Noise Model and Parameter Estimation
Authors: Cai Rui , Zhang Deng Yin
Published: April 2015

In transform domain distributed video coding scheme, we found that there was a certain deviation between Laplacian statistical distribution and the distribution of small and large residual coefficients. To reduce this deviation, this paper proposes a hybrid distribution correlation noise model (HDCNM) based on K-Mediods, which models small coefficients as improved Laplacian distribution while modeling large ones as Cauchy distribution. The parameter estimation algorithm is also given. The experimental results show that the hybrid model proposed in this paper can describe the distribution of residual coefficients between WZ frame and side information accurately, so as to improve the distortion performance of transform domain distributed video coding effectively, and reduce the computational complexity of decoder.
Prediction of Indoor Millimeter Wave Propagation Characteristics Based on BP Neural Network
Authors: Sun Zeng You , Li Huan Huan
Published: April 2015

Due to the complexity of the millimetre-wave indoor propagation environment, using the conventional methods to analyze propagation characteristics of radio wave leads to great error, and the computational complexity is high. In view of the above problems, the prediction method for propagation characteristics of the indoor millimetre wave based on BP neural network is proposed; using its function approximation to describe the millimetre wave propagation parameter, finding out the mathematical relationship between its corresponding external factors and the signal attenuation, the mathematical logic relationship is constructed through establishing the prediction model. Simulation results show that using this method can quickly and intuitively obtain the relationship between the propagation distance and field intensity or path loss, respectively, with advantages of taking short time and high computational efficiency.