bluuebunny/crossref_metadata_2025 huggingface dataset:
Slip Resistance of Floors in a Supermarket
Authors: Li Kai Way , Chen Ching Chung , Liu Li Wen , Chen Chih Yong
Published: June 2013

Floor slipperiness assessment was conducted in a supermarket in central Taiwan. The floor slip resistances in the meat cutting, cooking, and baking areas were measured. The friction measurements were conducted using the Brungraber Mark II slipmeter. The results showed that the slip resistance in the meat cutting areas was significantly higher (p<0.05) than those of the other two areas. The slip resistances between the cooking (0.49) and baking (0.51) areas were not significant. The slip resistance of the dry surface (0.64) was significantly higher than those of the wet (0.28) and oily (0.34) surfaces. The slip resistances between the wet and oily surfaces were not significant. All the wet and oily floors in the shop had COF values lower than 0.5, a safety standard commonly adopted in the USA. Ergonomic interventions were recommended.
An Evolutionary Game Study on the Sustainable Product Development in Remanufacturing
Authors: Zong Xian Ling
Published: June 2013

The remanufacturability of product is mainly determined by product design and development strategy. But now most products are designed without considering the remanufacturing and recycling process. It is necessary to study manufacturers product design behavior to find measures to encourage environmentally favorable product design. Sustainable product development behavior of manufacturer population in remanufacturing was studied. An evolutionary game model with government subsidies was set up. And the evolutionary stable strategies were analyzed under different ranges of values of relative parameters. The results indicated that government subsidies were essential to make manufacturers develop sustainable product and large subsidies always worked well. Especially the results showed that small subsidies also worked under certain conditions, which including the initial state of manufacturer population and the relationship of government subsidies and manufacturers revenues under different product development strategies.
China's Railway Transportation Network Christopher Research
Authors: Lv Gao Yan , Zhou Jian Qin , Bian Wen Liang
Published: June 2013

Based on China railway freight transportation network, this paper builds the railway transport network. Then, according to uneven distribution of capacity and the problems of asymmetric information, low efficiency of railway freight transportation, the paper puts forward the resolving method by whole network Christopher of the social network analysis. In this paper, according to the China railway transportation network statistics results of China railway freight transportation network Christopher, whole Christopher coefficient is 0.39. Originally, the study also concluded that the degrees of freight volume, using to finding out the problems of multiple nodes, sorting and take the strategy to improve group coefficient better. All in all, this paper solved the problem of China railway network understanding and gave advice for improving China's railway transportation economic benefits.
The Application of Information Technology in Green Supply Chain
Authors: Yu Qiang , Liu Lan Lan
Published: June 2013

In recent years, with the rapid development of world economy, people's living standards and cultural quality improved significantly, However, the consumption of resources is also more and more , since the scarcity of non-renewable resources and the pollution of the environment increasingly aggravated, all of countries have enacted strict environmental protection law to define the environmental protection obligations of the enterprise. to achieve the purpose of environment protection and sustainable development, building a green supply chain management system is very necessary and important. Green supply chain is to realize the economic sustainable development and an important means of environmental protection a win-win situation. This article focuses on the IT technology and modern information technology in the application of the green supply chain management, such as realizing green production, green logistics.
Financial Subsidies and their Effects on Environment-Friendly Products Supply in Green Supply Chain
Authors: Hou Fang Miao
Published: June 2013

The supply of environment-friendly products is an integral part of the green supply chain. Due to such reasons as lack of high-tech and lack of price competitiveness in contrast to traditional products, the manufacturers will not have incentive to produce and supply green products, so the Government should grant financial subsidies to producers which will compensate the profits entitled to them. Through the analysis based on game theory, the article concludes that there is disadvantage in constant subsidy and the variable subsidies will have more positive effects on the supply of environment-friendly products since the subsidy amount varies with the production scale.
Multi-Agent Applied Research in Agile Supply Chain
Authors: Tang Jin Peng , Li Ling Lin
Published: June 2013

Introduced intelligent agents to agile supply chain, designed multi-agent coordination mechanism for agents, then proposed agile supply chain based on multi-agent system. This mechanism is applied to a specific enterprise. Multi-Agent strengthens the agile supply chain system reliability, flexibility and scalability, and improves the competitiveness of enterprises.
Service-Oriented Manufacturing Agility and Application Based Flexibility
Authors: Xu Xuan Guo , Li Xiao Fei , Wang Yun Fei
Published: June 2013

Introduced flexibility index method to study service-oriented manufacturing enterprise agility. Analyzed agility needs and elements of service-oriented manufacturing enterprise: customer participation, manufacturing network, mass customization mode and information integration platform. According to CTRS(Cost, Time, Robustness and Suitability) norm defined elements flexibility index. Results show elements resource utilization factor has a significant effect of agility while the time dimension is weak. Enterprises can shorten manufacturing and R & D time and expand marketing channels to improve the overall agility.
Developing Automated Production Management System for Manufacturing Green IT Products
Authors: Shim Sang Oh
Published: June 2013

This paper presents a scheduling method for a semiconductor wafer fabrication to meet daily quantities of orders with multiple product types and different due dates. Since each order has a due date, a quantity to be produced and a product type, a production planning is made to satisfy meeting due date and quantity of order. By a production planning, the daily output quantities (to be transported to wafer probe facilities) and input quantities for all product types are determined and lots associated with orders are released to a fabrication. Although production planning is obtained, it is not easy for operators and manufacturing managers to observe production planning since the unexpected incidents, such as machine breakdown, operators' mistakes and preventive maintenance, occur frequently. Therefore, it happens frequently that actual daily output quantities of orders are different with the planed ones. In this paper, to satisfy production plans in real fabrication, efficient dispatching rule that can be used in scheduling and dispatching in manufacturing execution system for a semiconductor fabrication developed.
Application of PDCA-Cycle on the Management of Critical Values Reporting
Authors: Wang Hong , Chang Ying , Che Wen Sheng
Published: June 2013

Objective: Through the PDCA (Plan-Do-Check-Act, also called quality loop) cycle in the management of Critical Value Reporting, and then the discussion on the values of their application in the medical field. Methods: Data were divided into two groups (January to March in 2012 as before the implementation of PDCA-cycle and August to October as after the implementation of PDCA-cycle). Statistical analysis was applied for these two groups. Results: After the application of PDCA-cycle, the executing rate of critical values reporting increased from 38.2% to 96.4 % (P=0.000). The percentage of reporting time, repeat critical values reporting, reporters name and staff number, receivers name and staff number rised from 96.4%, 83.6%, 83.6%, 69.1% to 100.0%, 98.8%, 98.8%, 99.8%, respectively (P=0.000). Meanwhile, critical values reporting rate of Laboratory and Radiology also increased from 47.9%, 30.6% to 96.5%, 96.3% (P=0.000). Conclusion: This study suggested that the PDCA-cycle is an important tool for quality management, and it can effectively improve the executions of critical values reporting.
Study on Browning Degree of Fresh-Cut Purple Sweet Potato and its Inhibition during Storage
Authors: Gao Lu , Li Ke Da , Zhu Min Peng , Li Ying Chang
Published: June 2013

The basic study on activity of polyphenol oxidase (PPO) from purple sweet potato (PSP) and its control method was mainly carried out by spectrophotometry. The PPO activity and browning degree (BD) of PSP peel were higher than those of inner-tissue and intact sweet potatoes. The relativity between them was positive, and relativity coefficient was 0.9895. The activity of PPO extracted from sliced PSP increased initially and decreased afterwards, with the highest activity of PPO on the third day during storage. And BD increased very quickly as time went by, especially in the first three days. The relativity between PPO activity and BD was negative, and relativity coefficient was-0.8747. The result indicated that the browning of fresh-cut PSP slices during storage was mainly due to PPO in it. The composite inhibitor was optimized by the orthogonal design, and the addition of 0.05% L-cysteine+0.03% phytic acid+0.3% ascorbic acid+0.3% citric acid would markedly inhibit the enzymatic browning caused by PPO and improve the quality of fresh-cut PSP slices.
Beneficiability Study of the Blast Furance Dust from Tangshan Iron and Steel Company
Authors: Zhang Jin Xia , Niu Fu Sheng , Li Li , Xie Jun
Published: June 2013

Through the analysis and study the properties, characteristics and present conditions of the flue slime of blast furnace dust, a suggestion was made of recovering carbon and iron concentrate from the blast furnace dust using a beneficiation technology consisting of gravity separation-flotation. The laboratory test results indicated that it can obtain the iron/carbon concentrate with a grade of iron 53.41%, carbon 65.21% at a recovery rate of iron 51.33%, carbon 69.29%. This mineral processing technology achieved good technical and economical results, reaching the expected effect. The technology can be applied in production and popularized.
Effects of Temperature on the Growth and Product Accumulation of Chlorella sp.
Authors: Lu Bi Lin , Qi Liang , Li Ming Xi
Published: June 2013

In recent years, the use of liquid biofuels in the transport sector has shown rapid global growth, driven mostly by policies focused on achievement of energy security, and mitigation of GHG emissions. Microalgae, as biomass, are a potential source of renewable energy, and they can be converted into energy such as biofuel oil and gas.In this paper, the microalgae strain of Chlorella sp. was supplied in BG11 medium, and Cultivation optimization were experimented. The results were showed that temperature was an important factor which could influence growth and accumulation of secondary metabolite in the cell from accumulation process of biological products, temperature which was suitable for the growth of chlorella was 25°C.
Environmental Dyeing Technique - The Application of Low Liquor Ratio Dyeing
Authors: Liu Jin Fa , Zeng Xian Ping
Published: June 2013

Factors affecting reactive dyeing in the laboratory by 1:4 bath ratio was analyzed, such as dyes behaviors, dye bath circulation, dyeing conditions. Dyeing in the laboratory was carried out respectively with deep-color RW and light-color RW dyes by 1:4 bath ratio. By measuring levelness and K/S value of the dyes and color fastness.
Application of TOPSIS Model Based on Vague Set Entropy in the Evaluation of Groundwater Quality
Authors: Yu Wen Zhong , Tang De Shan
Published: June 2013

Groundwater quality assessment had important guiding significance on sustainable use of groundwater resources. In order to avoid the subjective judgment on the weight of each index, this article used the Vague set entropy theory to determine the weight of each index, combined with the TOPSIS method, it established the TOPSIS groundwater quality evaluation model based on Vague set entroy. Finally, this model was applied to groundwater quality evaluation in Tailan River Irrigation District, the evaluation results matched with the actual situation. The results showed that the evaluation process of this model was reasonable and scientific, it provided a new idea for groundwater quality assessment.
Copper Pollution and its Assessment of Roadside Soils in Suzhou City
Authors: Han Ya Fen , Li Qi
Published: June 2013

Heavy metal concentration in the roadside soil collected from the four directions was determined by X-Ray Fluorescence Spectroscope. The results indicated that the average copper concentration is higher than the soil background value of Anhui province and Cu was highly enriched and accumulated; the order of copper concentration from high to low is: Commercial areas > Areas around station > Industrial areas > Residential areas >Urban green space; the pollution assessment results of Geo-accumulation index showed that some samples((19, 23 ,26 and 29) is less moderate pollution or moderate pollution, , and the others are light pollution or unpolluted.
Removal of Cadmium Ions from Aqueous Solution by Nanostructured Carbonated Fluorapatite Bearing Siliceous Phosphorite
Authors: Shi He Bin , Liu Yu , Zhong Hong , Tian Xing , Liao Ming Hang
Published: June 2013

A middle grade siliceous phosphorite from Yunnan province was selected to treat Cd2+ bearing aqueous solutions. The siliceous phosphorite was tested by X-ray fluorescence spectrometer, X-ray diffraction, infrared spectrometer and scanning electron microscopy. The results present that the valuable mineral is nanostructured carbonated fluorapatite and the major gangue mineral is quartz. The amount of Cd2+ sorbed by the siliceous phosphorite tends to increase with the increase of initial pH or the initial Cd2+ concentration of the simulated waste water. The reaction process of Cd2+ removal from aqueous solutions is highly fitted with the pseudo-second order kinetic model. The results indicate that nanostructured carbonated fluorapatite bearing siliceous phosphorite can effectively immobilize aqueous Cd2+.
Preparation of ε-Polylysine Modified Silica Nanoparticles
Authors: Tan Zhi Lei , Xing Bei , Jia Shi Ru , Yao Fang Lian
Published: June 2013

Gene vector system is the key to realize gene transduction and therapy. A proper gene vector can introduce the target gene into cells securely, efficiently, controllably and easily, and achieve purposes of gene transfection and disease treatment after its expression. ε-polylysine (ε-PL),which is rich in cationic and has high penetrability through biological membrane,can be applied in DNA carrier. In this study, we presented a novel approach for preparing ε-polylysine modified silica nanoparticles and combinating them with plasmid DNA.
Adsorption of Cr Ion by Activated Carbon Prepared from Corncob Xylitol Residue
Authors: Xue Jing Wen
Published: June 2013

Corncob xylitol residue was soaked with H3PO4 for 16h and carbonized in microwave for 9min to obtain activated carbon. Methylene blue and iodine adsorption values were determined and were 119.92mg/g and 839.47mg/g, respectively. The adsorption property on Cr6+ was determined and the proper adsorption condition was pH2, 30min, 80°C. The maximum Cr adsorption capacity was 50mg/g.
Deformation Heating and Its Effect on the Processing Maps of Ti-15-3 Titanium Alloy
Authors: Zhang Jing Qi , Di Hong Shuang , Wang Xiao Yu
Published: June 2013

In the present study, deformation heating generated by plastic deformation and its effect on the processing maps of Ti-15-3 titanium alloy were investigated. For this purpose, hot compression tests were performed on a Gleeble-3800 thermo-mechanical simulator in the temperature range of 850-1150 °C and strain rate range of 0.001-10 s1. The temperature rise due to deformation heating was calculated and the as-measured flow curves were corrected for deformation heating. Using the as-measured and corrected flow stress data, the processing maps for Ti-15-3 titanium alloy at a strain of 0.5 were developed on the basis Murty‘s and Babu’s instability criteria. The results show that both the instability maps based the two instability criteria are essentially similar and are characterized by an unstable region occurring at strain rates higher than 0.1 s1 for almost the entire temperature range tested. The unstable regions are overestimated from the as-measured data due to the effect of deformation heating, indicating a better workability after correcting the effect of deformation heating. This is further conformed by the analysis based on strain rate sensitivity.
Microstructure and Mechanical Properties of Al-12.7Si-0.7Mg Alloy Welded Joints Using Homogeneous Welding Wire
Authors: Wang Hao , He Chang Shu , Zhang Hong Jun , Wang Dong , Zhao Xiang , Zuo Liang
Published: June 2013

A novel Al-12.7Si-0.7Mg welding wire was successfully produced via DC casting, extrusion, roll die drawing and hole die drawing. An investigation was performed on the microstructure and mechanical properties of the welded joints using the as-produced special filler wire in different solid solution and artificial aging treatment conditions. The results showed that the as-produced Al-12.7Si-0.7Mg welding wire was an ideal special wire of the Al-12.7Si-0.7Mg wrought alloy and the homogeneous welded joints proved to be heat-treatable. Solid solution treatment and artificial aging treatment had significant influence on the microstructure, microhardness and tensile properties of the as-welded joints. A transformation of microstructures from a coarse structure to a fine structure occurred in the welded joints after the heat treatment. The microhardness and the strength of the joints increased remarkably as the solution temperature and aging time increased.
Characteristics of YAG-MIG Hybrid Welding 6061 Aluminum Alloy with Different States
Authors: Xu Fei , Guo Ya Fei , Chen Li , Yang Jing
Published: June 2013

With the diversification of manufacture methods, joining the same materials with different states becomes indispensable in practical application. The hybrid welding has broad application prospects. It not only reduces the strict assembled gap before welding, but also improves the joint properties by filling wire during the welding process. 6061 aluminum alloys with different states were welded by YAG-MIG hybrid welding. The characteristics of welded joint, including microstructures, the tensile properties, microhardness and fracture, were investigated. The results show that the microstructures are different significantly in different states. Besides, the grain boundaries of the joint microstructures become unclear after heat treating. The strength and the elongations of welded joints could reach to that of the base metal. The tensile fracture occurs in the fusion zone and near 6061-O alloy. And the fracture presents ductile rupture. Meanwhile, the effect of the small pores in the weld on the joints tensile properties is slight.
Study on Microstructure of a Gear Shaft during Hot Forging Process
Authors: Wang Guang Chun , Hao Bin Hai , Feng Chao , Wang Tao
Published: June 2013

The microstructure revolution of a spur gear shaft during hot forging was numerically simulated with FEM using Yada Model. The grain size distribution of the gear shaft after hot forged using initial billets with different dimensions was obtained through microstructure simulation and relative metallographic experiment show a good agreement with the simulation result. Effect laws of different forging parameters including the initial forging temperature and the punch speed, on grain size of the gear shaft after forged were given. A preforming process was proposed and the microstructure simulation shows that the preforming process can significantly improve the grain size refinement and distribution uniformity of the gear shaft by hot forging.
Exploiting the Influence of Oxidization on Ultra-Fine Copper and Nickel Sulfide Containing Pt-Pd in Yunnan Mine
Authors: Tang Min , Ge Bao Liang , Wen Shu Ming
Published: June 2013

It is known that oxidation is one of the most common ways for penlandite to be introducted into tailing during traditional coarse-particle sulfide flotation. However, it could become much more complicated and challenging problems for the low-grade, fine-disseminated Cu-Ni sulfides containing Pt and Pd in Yunnan Mine, accompanied with more than 75% of the content of MgO in the ore sample is. Direct flotation tests had been conducted to extract the metallic values as much as possible by adding traditional depressants and collectors, such as carboxylmethyl cellulose, starch, sodium silicate, butyl xanthate, (BX), butyl ammonium dithophosphate (BA) and etc., the relatively satisfied recoveries of Cu, Ni, Pt and Pd in the concentrate from bench flotation tests were obtained, however, more than 30% of metallic values still lost in the slime. In this study, bench flotation tests for the ore sample fromYunnan Mine, micro-flotation tests of serpentines and pentlandite from Jinchuan Mine and their settling rate tests were conducted to figure out how the oxidation influence the recovery of the ultra-fine nickel sulfide. All the tests results pointed to the presence of over-oxidation on the ultra-fine nickel sulfide surface and lead to the loss of Ni containing Pt and Pd in the slime tailing. Some methods which tried to slow the speed of oxidation on mineral surface during grinding and flotation were introduced in order to recover the values before over-oxidation of sulfides; however, the slime coating of serpentines also may play an important role in disturbing the floatability of ultra-fine sulfide.
The Construction, Problems and Solutions of Yunnan Germanium Technology Chain
Authors: Li Fu Chang
Published: June 2013

Germanium technology chain is technically interdependent between germanium intra-industry and industry, as a technical interface between the "chain", it's a series of processes between germanium intra-industry and related industries for the products or services of the final transaction the germanium. Yunnan has initially formed set germanium mining, deep processing, research and development of more complete integration of germanium technology chain. But Yunnan downstream processing technology chain only extended to the end products, accessories production. And the high value-added end products do not yet have the production technology to build a competitive technology chain. Therefore, Yunnan has to improve the technical level of the prior art chain, integrated innovation of technology chain, the introduction of the end-product technology chain, vigorously develop the build germanium manufacturing technology chain, development germanium reverse reuse, recycle, recycling and environmentally friendly processing technology chain positively .So that Yunnan technology chain can be developed and improved very well.
The Study on the Warm Mix Asphalt Mixture Ratio
Authors: Wang Yong Hong , Tan Xi Ming , He Xiong Jun , Wu Li , Dong Bo , Zhou Si Quan
Published: June 2013

The temperature has been reduced in the aggregate heating, mixing, transportation and paving for Warm mix asphalt mixture (WMA),but the temperature of hot mix mixes has no diversification. So the mixing ratio of warm mix asphalt mixed material cannot be completely designed to the HMA and it should be designed by the mixing ratio of WMA. Through analyzing the relationship of aggregate moisture content and getting the performance of the allowed moisture . Combining with the principle of conservation of energy and laboratory to get the conclusion of the aggregate heating time and heating temperature, in order to calculate the construction control parameters, and it will promote the application of asphalt pavement in the construction.
Properties of Alkli-Activated Slag Cement Compounded with Soluble Glasses with a High Silicate Modulus
Authors: Pan Qun , Zhu Bin , Huang Xiao , Liu Lin
Published: June 2013

Properties of alkali-activated slag cements compounded with soluble glasse with a high silicate modulus Ms=2.6 were detailedly studied in this paper, including compressive strength and flexure strength characterictics at the ages of 3,7,28 days and flow values of fresh cement mixtures on a jolting table. As a result, with the compressive strength at the age of 28 days of 95.6-107.8 MPa has been developed, and the flow values and strength characteristics of alkali-activated slag cement mortars increased with increase in a water to cement (alkaline activator solution to slag) ratio, and the flow value (determined on the cement mortar mixtures) would reach 145 mm. Moreover, the development speed of strength characteristics of mortar specimens would be affected negatively by increasing of water demand (requirement).
Use of Septic Tank Sludge as Raw Material in the Manufacture of Bricks
Authors: Ingunza Maria Del Pilar Durante , Lima Andressa Dantas , Araujo Andre Luis Calado
Published: June 2013

The present paper analyzes the feasibility of using septic tank sludge subsequently treated in an anaerobic pond as raw material in the ceramic industry. An experiment was conducted involving the manufacture of 500 bricks using 6.5% (dry weight) of sludge at a ceramic plant in the Northeast of Brazil. To reproduce the methodologies, the same conditions and methods used by the local ceramic industry were adopted. To evaluate the bricks produced and environmental risk, compressive strength, water absorption and lixiviation tests were carried out, obeying current Brazilian norms, according to international standards. Results show the technical feasibility of using sludge as raw material in the red ceramic industry, highlighting the firing temperature of the bricks as a determinant variable. Moisture content of the sludge-clay mixture emerges as limiting factor in the manufacturing process. The moisture value determined as acceptable in the study was 22%.
Development of Wear Resistant Cast Steel and Its Study on Mechanical Properties
Authors: Li Hong Bo , Wang Jing , Cheng Han Chi , Li Chun Jie , Su Xing Jun
Published: June 2013

This paper mainly through the experimental study on the heat treatment process and mechanical properties of cast steel 35CrMnSiMo.According to the effect of alloy elements in design of a high-toughness abrasion-resistant cast steel, Cr, Mn, Si, as the main alloy elements, supplemented by a small amount of Mo, the casting molding, for hardness and impact toughness test of mechanical properties of experimental steel. The results show that, the as-cast 35CrMnSiMo by 880 °C, quenching for 20min then, the same quenching temperature, quenching hardness of materials is far greater than the oil quenching hardness. Water quenching hardness up to 25% higher than the oil quenching hardness, The impact toughness of specimen is inversely proportional to the contrast relationship Hardness.
Simulation and Experimental Mechanical Properties of SiCn/2024 Al Alloy Co-Continuous Composites
Authors: Qin Yi Wei , Lu Sen Kai
Published: June 2013

The experimental and numerical simulations of mechanical properties of co-continuous composites SiCn/Al produced by infiltration of SiC preforms with melted 2024 Al alloy using Solidwork2012 Simulation code were carried out. The results showed that ultimate tensile strengths of SiCn/Al up to 410 MPa at a failure strain of up to 0.7% without any heat treatment. The compression strength was up to 710 MPa with 2% strain to failure. The composites show an excellent resistance to high cycle fatigue. Fatigue life for specimen was 4.5×105 cycles for 250 MPa while R=-1.0, and 4.9×105 cycles for 164 MPa while R=-0.05. Simulated data shows there is different mechanical behavior between SiC structs and Al matrix, difference of elasticity modulus of two constituents occasion difference of generated deflection, Al has taken place large deformation; Due to structural characteristic of SiC, the force on each rib affects other adjacent rib, Al and SiC restrict each other to prevent from producing the strain.
Optimal Structural Health Monitoring Feature Selection via Minimized Performance Uncertainty
Authors: Mao Zhu , Todd Michael D.
Published: June 2013

Power spectral measurements are very ubiquitous for their utility in generating structural health monitoring (SHM) features, because of their clear physical interpretation and easy computation through Fourier transform. In most SHM applications, optimal features are always desired to perform whatever level of assessment is required. Optimal in this sense refers to a measure of performance capability to enhance decision-making, because structural health monitoring inevitably involves, at some level, a hypothesis test: in the binary case, the question becomes are the features extracted from data derived from a baseline condition? (baseline can also mean linear, or any reference condition designated the null hypothesis) or ...from data derived from a different (test) condition. Inevitably, this decision involves stochastic data, as any such candidate feature is compromised by noise, which we may categorize as (i) operational and environmental, (ii) measurement, and (iii) computational/estimation. Regardless of source, this noise leads to the propagation of uncertainty from inception to final estimation of the feature; in all cases, the subsequent distribution of the features can lead to significant false positive (Type I) or false negative (Type II) errors in the classification of the features via the hypothesis test.
Frequency domain approaches for SHM typically involve estimation of some form of transfer function, typically the usual frequency response function (FRF). Based upon the statistical modeling of the uncertainty of feature estimations, this paper evaluates the performance of two FRF-derived features, namely the dot-product difference (DPD) and Euclidian distance (ED), and statistical significance detection qualities are quantitatively compared. In each of the feature evaluations, the performance comparison is executed under the condition of best trade-off between sensitivity and specificity, adopting receiver operating characteristics as the performance indicator. Monte Carlo simulation and lab-scaled tests on plate-like structures are both implemented to validate the optimal feature selection process and demonstrate performance enhancement. The comparisons are facilitated through computation of receiver operating characteristics (ROCs), which are data-driven methods for comparing detection rates to error rates as a function of decision boundaries established between data distributions, independent of the actual underlying distribution.
Imaging Damage Using Mixed Passive and Active Sensors
Authors: Wang Chun H. , Francis Rose L.R.
Published: June 2013

Existing damage imaging techniques rely on the use of active sensors, such as piezoelectric actuators, that can both transmit and receive guided waves. This paper presents a new time-reversal imaging approach to enable the use of passive sensors, such as optical fibre sensors and strain gauges, to augment active sensors for imaging structural damage. Computational simulations have revealed that damage size and severity can be accurately determined from the scattered wave using as few as six sensors: one active sensor and five passive sensors.
Distributed Strain Monitoring for Damage Evolution in CFRP Bolted Structures with Embedded Optical Fibers
Authors: Takeda Nobuo , Minakuchi Shu , Nadabe Takeyuki
Published: June 2013

The authors proposed fiber-optic-based damage monitoring of carbon fiber reinforced plastic (CFRP) bolted joints. Optical fibers were embedded along bolt holes and strain change along the optical fiber induced by internal damage was measured by a Brillouin Optical Correlation Domain Analysis (BOCDA), which is a high spatial resolution distributed strain sensing system. This study began by investigating damage modes of CFRP bolted joints after bearing failure. Effective embedding positions of optical fibers were then proposed and their feasibility was evaluated by finite element analysis simulating the damage propagation in the bolted joint and consequent strain change. Finally, verification tests were conducted using specimens with embedded optical fibers at various positions. It was clearly shown that damage could be detected using residual strain due to fiber-microbuckling (kinking) damage or permanent deformation of neighboring plies. Furthermore, damage size and direction could be estimated from the change in the strain distribution. The system developed is quite useful for a first inspection of large-scale composite structures in aerospace applications.
Active Evacuation Guidance and Structural Health Monitoring System for Buildings Using Sensor Agent Robots
Authors: Mita Akira , Ise Daiki
Published: June 2013

Active evacuation guidance using a sensor agent is explored. The sensor agent robot is equipped with a high precision servo-accelerometer with a uplifting mechanism for axles to ensure accurate measurement of floor response. The story drift angle is estimated from the acceleration data obtained by the sensor agent robot to decide whether evacuation is needed or not. This sensor agent robot is used for services in the living space in a normal situation. Thus, the evacuation system can be economical and feasible as the system for this evacuation added to the robot is small.
Sensor Agent Robot with Servo-Accelerometer for Structural Health Monitoring
Authors: Akiba Tatsuya , Lee Nobukazu , Mita Akira
Published: June 2013

SHM systems are becoming feasible with the growth of computer and sensor technologies during the last decade. However, high implantation cost prevents SHM from becoming common in general buildings. The reason of this high cost is partially due to many accelerometers. In this research, we propose a mobile sensor agent robot with accelerometers and a laser range finder (LRF). If this robot can properly measure accurate acceleration data, the cost of SHM would be cut down and the SHM systems would become common. Our goal is to develop a platform for SHM using the sensor agent robot. We designed the prototype robot to detect the floor vibrations and acquire the micro tremor information correctly. When the sensor agent robot is set in the mode of acquiring the data, the dynamics of the robot should be tuned not to be affected by its flexibility. To achieve this purpose the robot frame was modified to move down to the floor and to provide enough rigidity to obtain good data. In addition to this mechanism, we tested an algorithm to know the location of the robot and the map of the floor correctly to be used in the SHM system using the LRF and Simultaneously Localization and Mapping (SLAM).
Locating Point of Impact on an Anisotropic Cylindrical Surface Using Acoustic Beamforming Technique
Authors: Nakatani Hayato , Hajzargarbashi Talieh , Ito Kaita , Kundu Tribikram , Takeda Nobuo
Published: June 2013

A beamforming array technique with four sensors is applied to a cylindrical geometry for detecting point of impact. A linear array of acoustic sensors attached to the plate record the waveforms of Lamb waves generated at the impact point with individual time delay. A beamforming technique in conjunction with an optimization scheme that incorporates the direction dependent guided Lamb wave speed in cylindrical plates is developed. The optimization is carried out using the experimentally obtained wave speed as a function of propagation direction. The maximum value in the beamforming plot corresponds to the predicted point of impact. The proposed technique is experimentally verified by comparing the predicted points with the exact points of impact on a cylindrical aluminum plate and a cylindrical composite shell. For randomly chosen points of impact the beamforming technique successfully predicts the location of the acoustic source.
Recent Progress in Intelligent Vehicle Health Monitoring
Authors: Cole Ivan S. , Corrigan P. , Ganther W.D. , Galea Steve C.
Published: June 2013

Boeing, CSIRO and DSTO are collaborating on research into Intelligent Health Monitoring for Aerospace Vehicles (IHMAV). The system has the ability both to predict the probable development of corrosion and to elucidate the environmental factors that are promoting corrosion. The paper discusses the system capabilities, data output including the data derived from previous monitoring programs on B-707. In particular this data established the connection between local microclimate and corrosion events and highlights variations in microclimate and corrosion that can occur for different spaces in an airframe and different airframes.
Structural Health Monitoring of Research-Scale Wind Turbine Blades
Authors: Taylor Stuart G. , Farinholt Kevin M. , Park Gyu Hae , Farrar Charles R. , Todd Michael D. , Lee Jung Ryul
Published: June 2013

This paper presents ongoing work by the authors to implement real-time structural health monitoring (SHM) systems for operational research-scale wind turbine blades. The authors have been investigating and assessing the performance of several techniques for SHM of wind turbine blades using piezoelectric active sensors. Following a series of laboratory vibration and fatigue tests, these techniques are being implemented using embedded systems developed by the authors. These embedded systems are being deployed on operating wind turbine platforms, including a 20-meter rotor diameter turbine, located in Bushland, TX, and a 4.5-meter rotor diameter turbine, located in Los Alamos, NM. The SHM approach includes measurements over multiple frequency ranges, in which diffuse ultrasonic waves are excited and recorded using an active sensing system, and the blades global ambient vibration response is recorded using a passive sensing system. These dual measurement types provide a means of correlating the effect of potential damage to changes in the global structural behavior of the blade. In order to provide a backdrop for the sensors and systems currently installed in the field, recent damage detection results for laboratory-based wind turbine blade experiments are reviewed. Our recent and ongoing experimental platforms for field tests are described, and experimental results from these field tests are presented. LA-UR-12-24691.
Understanding of the Scattering of Incident Stress Waves by Defects on the Blind Side of Fuel Vent Hole
Authors: Doherty Cain , Chiu Wing Kong
Published: June 2013

This paper reports on findings that extend previous work for the purpose of in-situ structural health monitoring of defects on the blind side of open holes using plate waves. A series of computational studies is presented to understand how and why the ultrasonic scattered wave field can be detected on the accessible surface. The uniqueness of these findings is that the length-scale of the defect and the incident waves are comparable. The combination of the experimental-computational-analytical approach gives rise to new insights and guidance for the quantification of defects located in hard-to-inspect regions of future unitised metallic and composite structures. The outcomes advance the knowledge base of inspection of hard-to-access regions with actuators and sensors placed in easily accessible locations.
Novel Transducer for Characterization of Low-Impedance Materials
Authors: Dugnani Roberto
Published: June 2013

Piezoelectric materials such as lead-zirconate-titanate (PZT), lead-metaniobate, and piezo-composites are the materials of choice for acoustic imaging in medical diagnosis as well as underwater ultrasonic microphones and underwater sonar. PZT materials have the advantage of having high electro-mechanical coupling, low internal losses and excellent environmental durability. Nonetheless, in order to improve energy transmission the high acoustic impedance of piezoelectric ceramics needs to be matched to the lower acoustic impedance of biological tissues and water. For actuators resonated in their thickness mode, energy transmission can be improved by means of intermediate layers of material of carefully selected thicknesses and acoustic properties. Sometimes a backing layer is also added to the back of the actuator to damp the acoustic back-wave. The process of making these types of transducers is generally costly due to the nature of the manufacturing process and the required level of accuracy. This paper describes an inexpensive method of manufacture low-cost, low-impedance, piezoelectric transducers. The fundamental physical principles behind this new type of sensor-actuator, as well as various examples of imaging low-impedance targets using a prototype of this newly developed sensor-actuator system will be presented.
Modal Acoustic Emission Investigation for Progressive Failure Monitoring in Thin Composite Plates under Tensile Test
Authors: Zohari Mohd Hafizi , Epaarachchi Jayantha Ananda , Lau K.T.
Published: June 2013

Acoustic Emission (AE) is one of the popular non-destructive (NDT) techniques and its applications have increased subsequently for Structural Health Monitoring (SHM). During the past few decades, many successful research works have evidently shown remarkable capability of AE for early damage detection of composite materials. This paper investigated the application of single channel acoustic emission (AE) source location detection method, utilizing time-frequency analysis for thin composite plates. Besides, failure characterization using Modal Acoustic Emission (MAE) also presented. Modal analysis of AE signals or MAE can offers a better theoretical background for acoustic emission analysis; which is necessary to get more qualitative and quantitative result and therefore, increase the reliability of early failure characterization for thin composite plates. For this study, tensile tests were conducted on the glass fiber epoxy resin specimen with small notch; and four channels of acoustic emission system were used to acquire AE signals. The results revealed that in practical, single channel AE source location was difficult to be done. Also, the study has successfully showed that matrix cracks and fiber fracture produced AE signals which dominated by symmetric wave mode.
Improvement of Thermal Polyurethane Adhesive Compositions Parameters by Modification with Zeolite
Authors: Kozar Oksana P. , Oliynykova V.V. , Konoval V.P.
Published: June 2013

The aim of this study is to improve the heat resistance performance of polyurethane based adhesives for the manufacture of shoes. Four polyurethane adhesive compositions most used in the domestic shoe industry have been investigated: PU-503, VU-252, KYSPO-1 and D-274. The main components of polyurethane compositions are urethane rubber, zeolite, ethyl acetate and acetone. It has been found that modification of VU-252, KYSPO-1 and D-274 with zeolite in the amount of 0.5-1% allow to increase the heat resistance to 150° C while that of PU-503 - to 200° C. Besides it has been found that adhesive compositions can be recommended for the manufacture of special fire-resistant shoes that could withstand high thermal loads.
Compact Representation and Statistical Significance of Measurement Data Reflecting Electric Properties of Polymer Nanocomposites
Authors: Matīss Imants , Pentjušs Ēvalds , Krievs Oskars , Berzina Rita
Published: June 2013

The paper is devoted to investigation of frequency-dependent electric properties of polymer nanocomposites. The experimentally acquired frequency characteristics of complex dielectric permittivity are substituted by equivalent mathematical models of dielectric relaxation. It is shown that such substitution is valid, provided that the selected relaxation model allows shaping the synthesized frequency curves in a sufficient range and the statistical significance of the measurement data is within a satisfactory range.
Temperature Effect on the Shear Strength of Adhesively Bonded Joints
Authors: Osanai Kenji R. , Reis João M.L.
Published: June 2013

The purpose of this paper is to study some of the factors that affect the shear strength of Single Lap Joints (SLJ). Based in work conditions for different applications, tests were made in order to define the influence of geometry and temperature on the strength of SLJ under shear load. The adhesive used to make the joints was the epoxy adhesive ARC858 and it was tested under temperatures ranging between 21°C and 70°C and overlap length of 12.5mm and 18.75mm. Results of those tests showed that shear strength increased due to geometry with an overlap of 18.75mm and a great shear strength loss ranging from 30°C to 50°C. The failure mechanism was adhesive failure.
Mechanical Performance of Natural Fibers Reinforced Geopolymer Composites
Authors: Correia Edvaldo Amaro S. , Torres Sandro Marden , de Oliveira Alexandre Marcio Eliel , Gomes Kelly C. , P. Barbosa Normando , de Barros Silvio Romero
Published: June 2013

The use of geopolymers as matrix in composites with syntactical fibers have been studied and proposed in the literature. Nonetheless, for the best know of the authors, there are no researches about the use of geopolymers as matrix in composites with natural fibers. The use of natural fibers is increasing in the automotive industries. One of the problems to expand the use of natural fibers in composite materials is the low fire resistance of the classical type of polymers. In this sense, geopolymeric matrices open up horizons for this type of application. This paper studies composites with geopolymeric matrices reinforced with two types of natural fibers: sisal (Agave Sisalana) and pineapple leaf fiber (PALF-Ananas Comosus). The mechanical properties of these new composites are investigated by mechanical tests. The results confirm the increasing in the mechanical performance whenever the fibers are under traction stress.
Dynamics of 2-DOF Micro-End-Milling System Considering Grain-Size Variation
Authors: Araujo Anna Carla , Savi Marcelo A. , Calas Lopes Pacheco Pedro Manuel
Published: June 2013

Non-smooth systems are employed to model different cutting processes including milling and oil drilling. This article deals with the modeling of the micro-end-milling dynamics with inhomogeneous materials. The model considers a non-smooth system composed of a primary system that represents the tool and a secondary system, representing the workpiece. This system mimics micro-end-milling dynamics considering a progressive motion of the tool holder with tool run-out. The relative position of the tool holder and the chip is evaluated avoiding huge displacements of the tool tip when the tool is not in cutting. The simplified dynamics presented in this article is used as a methodology to calculate the cutting force and tool performance from the prescribed trajectory. The inhomogeneity is related to the description of the micro-machining process where material properties cannot be considered as constant due to grain structure as the tool moves for cutting. Numerical simulations consider a situation where the grain workpiece has austenitic, ferritic or ferritic-austenitic phases. Microscopic analysis is employed to obtain the property variations. The main goal is to establish a qualitative comprehension of the system dynamics comparing results with homogeneous material cutting process.