bluuebunny/crossref_metadata_2025 huggingface dataset:
Mechanical Property of the Deep Surrounding Hard Rock under Complex Environment
Authors: Liu Yong Sheng
Published: August 2013

The complicated geological condition of the deep roadway is the important factors to influence the stability of the surrounding rock and the safety of mining. The rock specimen is taken from a coal mining of Jiangxi province. The chemical solution with different ion concentrations and PH value were prepared to simulate the complex environment of the deep roadway, and the specimens were immersed in the solution then carried out the axial compression test. The strength and other mechanical parameters of the specimen were obtained and the experimental results showed that the strength of the specimen being immersed all are lower than natural state. The reduced values become large with the immersed time and acid value increasing.
Optimization Analysis of Pillar Position under Inclined Coal Seam Pillar
Authors: Liu Xin Jie , Wang Qing , Dai Jin , Fang Yi Fang
Published: August 2013

In order to get reasonable pillar position, this paper researched 20 m inclined pillar abutment pressure spread distribution rule on multiple inclined coal seam roof and floor, based on these lower coal seam have three pillar position can be determined, they were in the central or upside or downside. We are from three aspects to respectively analysis degree of pillar relief, pillars peak pressure concentration factor and pressure spread depth of the floor when pillar layout in different location. The results show that pillar abutment pressure concentration factor along the pillar normal and gravity synthesis direction spread, and with flat oval symmetrical decline distribution on roof and floor, also obtain the upper and lower pillar staggered arrangement is beneficial to the upper pillar pressure relief, at the same time, pillar itself abutment pressure peak coefficient is lower, floor propagation depth is smaller. In short, if the coal seam under inclined pillar want to layout pillars, upside better than downside, and downside is better than vertical, which the result has certain guiding significance for inclined coal seam of reasonable choice pillar position.
Geochemistry of late Permian Coals from the Yantang Mine in Xuanwei, Yunnan, China
Authors: Wang Juan , Shao Long Yi , Li Meng , Gao Cai Xia
Published: August 2013

16 samples included coals, roofs, floors and tonstein of Late Permian collected from Yantang mine, Xuanwei were characterized through a petrographic and geochemical investigation. The results showed that, Yantang coals are medium degree of coalification bituminous coals; between gas coal and rich coal; have middle to high ash yields; extraordinarily low sulphur except B2-4, and dominanted by pyritic sulphur. Yantang coals are mainly composed of vitrinite and inertinite. The major minerals are clay minerals and quartz, followed with calcite, pyrite, illite and so on. The contents of Cu, W, Zr and V in Yantang mine were higher than the coals of national and Permian of southern China. Pearson correlation analysis results show that Be, Ni, Tl, Th, Li, Ga, Cs, Zr and Hf and ash yields significantly related at the 90% confidence level (r=0.51-0.79), and it indicate the nine elements are combined in minerals in the coal or related with minerals closely.
Test Study of Water-Resisting Ability of Coal Seam Floor Rock Mass
Authors: Fan Cheng , Jing Xue Qing
Published: August 2013

According to Yang Zhuang coal mine engineering background and the actual situation, reasonable to determine the test site and experimental programs in this paper, and detailed description of the test method, and the final analysis of the coal seam floor water blocking capability, The results show that In low water pressure, the pressure of injection water in the hole with the water in the aperture of little contact, and in high water pressure will produce a good hydraulic connection. The study provides a theoretical foundation and scientific basis for the actual engineering improves safety.
The Affection of Ke of Coal Seam on Strata Behavior
Authors: Wang Wen Jie , Wang Hong Wei , Wang Zhao Hua , Xu Duo
Published: August 2013

Coal seam burst tendency is one of the main factors of rockburst. The impact energy index is an important indicator to evaluate bursting liability of coal. The research on the impact of coal seam impact energy index on the mining pressure behavior regularity is important for the rockburst prediction and prevention. This paper used FLAC3D numerical calculation software to simulate the mining process of seam workface with different Ke and studied the strata behavior regularity with different Ke. Calculations indicated that the vertical stress peak increased in the middle of the seam workface with Ke increasing and the peak position closer to face should implement the anti-impact measures. However, with Ke decrease, vertical stress superimposes at peak stress increases sharply, gradually increasing vertical stress peak distance away from the face and roadway coal wall and the peak position of moves away from face and roadway coal wall. Therefore, the stress in the roadway and face superimposed at the scour protection measures should be implemented.
Geochemistry of Sulfur in Extract from Hedong Coal Mine, China
Authors: Zhao Qiao Jing , Tang Yue Gang , Deng Xiu Jie , Yu Xiao Lei
Published: August 2013

The organosulfur compounds in the extract of the unusually organic sulfur rich of Hedong coal mine had been identified by gas chromatography and mass spectrometry. There are two series organosulfur compounds (OSC) were detected in the extract, they are benzonaphthothiophen and dibenzothiophene and the content of methylbiphenyl is overwhelming advantages in the biphenyl series. It demonstrates that the coal was formed in alkaline environment. The coal was formed in a reduction environment generally but there are exceptions, the samples HD9-2 and HD10-13 which have the value of Pr/Ph was 3.52 and 4.05 and So/St in sample HD9-2 was 78.82%, 73.08% in sample HD10-13 respectively . It show that the coal suffer strong oxidation and there are no good correlation between the content of organic sulfur and the oxidation environment.
Temperature Dependent Solid-Liquid Extraction Behavior of Rare Earths Using N-Butyl Pyridinium Hexafluorophosphate with Benzoyl Acetone
Authors: Pan Zhong Wei , Cai Zi Cheng , Bian Meng Jin , Lian Ting , Su Zeng Yi , Zhang Zhen Zhen , Huang Du Qing
Published: August 2013

Temperature dependent solid-liquid extraction (SLE) behavior of six rare earth elements (REs) was investigated using N-butyl pyridinium hexafluorophosphate ([BPy]PF6) as an ionic liquid solvent and benzoyl acetone (HA) as an extractant at 80 °C. Parameters including the amount of [BPy]PF6, HA concentration, extraction time, extraction temperature and pH were investigated and optimized. The extracted species was neutral REA(n-1)Cl (n-1 = 3 or 2) in the REn+-[BPy]PF6-HA SLE system. The extraction percentage of REn+ could be 100% at stated pH and HA concentration. The recovery of REn+ extracted into [BPy]PF6 can be achieved using the mixture of 0.1 mol·L-1 ClCH2CO2H and 0.2 mol·L-1 HCl as stripping agents. REs were extracted into solid ionic liquid phase with smaller volume and concentrated to some extent. Furthermore the temperature dependent SLE allows to recover [BPy]PF6 after the extraction procedures. These results indicate that the proposed procedure can be used for the preconcentration and separation of REs using [BPy]PF6 with high melting point.
Intensifying Magnetic Separation of Iron-Bearing Sulfide Minerals by Electron Beam Irradiation Pretreatment
Authors: Wang Huai Fa , Lu Shou Ci , Wang Cai Li
Published: August 2013

The changes of magnetic property of several iron bearing sulfide minerals after strong beam current electron irradiation are examined. Data shows that the magnetic susceptibility of arsenopyrite and chalcopyrite increases markedly compared to that of pyrite and marmatite. The magnetic susceptibility of arsenopyrite exceeds the lowest ferromagnetic limit 3000 cm3/g, while the susceptibility changes of other minerals are relatively slow. The irradiation dose is the dominate parameter determining the magnetic susceptibility change. Electron beam irradiation might be a potential method to enlarge the magnetic property distinction between the minerals for their magnetic separation.
Geoelectrochemical-Extraction Measurement Method to Look for Hidden Lead-Zinc Ore Deposit and Prospecting Effect
Authors: Hu Yun Hu , Liu Xi Jun , Luo Xiang Rong
Published: August 2013

The geoelectrochemical-extraction measurement is a ore prospecting method of deep-penetrating geochemistry, by using the element receptors to extract the mobile metal ions from the soil under the artificial electric field to look for the hidden ore deposit. The study of using the geoelectrochemical-extraction measurement method to look for blind lead-zinc ore deposit has been carried out in the Fuzichong lead-zinc polymetallic ore deposit and Panlong lead-zinc ore deposit of Guangxi, which resulted in the clearly geoelectrochemical anormaly above the known ore bodies. And the ore prospecting forecast conducted in the unknown ore regions shows that it is feasible to use the geoelectrochemical-extraction measurement method to expore the deep hidden lead-zinc ore deposits.
Mineral Processing Experiment Research of Low-Grade and Fine-Size Inseparable Lead-Zinc Ore
Authors: Yang Yong Tao , Zhang Jun Hui , Zhang Yuan
Published: August 2013

The processing experiment research was conducted on a certain fine-size and low-grade inseparable lead-zinc ore, in view of the characteristics of fine grain size composition and complex dissemination, under the conditions of grinding fineness of-325 mesh and content of 80%, as a result, the lead concentrate which has grade of 55.38% lead and recovery of 46.11% and zinc concentrate which has grade of 48.67% zinc and recovery of 66.42% were produced by adopting mineral processing flowsheet of "lead-sulfur of differential flotation partial cyclic flotation of zinc middling regrinding separations of lead and sulfur".
Present Status of China's Hematite Processing Technology Study
Authors: Li Feng Jiu , Qu Yun Long , Li Fu Ping , Zhang Jin Rui
Published: August 2013

This paper describes the hematite beneficiation technology progress and equipment,the current research has through biological flotation, flotation and selective aggregation separation process for separating iron minerals.Can reach a maximum of iron grade of 67.50%, metal recovery rate of 75% of the final concentrate of current hematite beneficiation process for gravity separation magnetic separation reverse flotation process.
Recovery Copper from a Low Grade and Ultra-Fine-Grained Dissemination Mixed Copper Ore by Flotation
Authors: Xian Yong Jun , Wen Shu Ming , Shen Hai Ying , Nie Qi
Published: August 2013

The present study aims to characterize the copper ore from east area of Yunnan province. The results indicate that the ores is a representative low grade and and ultra-fine-grained ore. As a result, a suitable flotation flow i.e. “ultrafine grinding- sulphidizing and dispersing - bulk flotation with low dosage collector” was presented for processing of eligible copper concentrate with high recovery and the main factors i.e. grinding fineness, regulators types and dosage and collector dosage affecting the indexes of roughing concentration was investigated. As a result, a close-circuit flotation test scheme was proceeded, which obtained a high quality copper concentrate with Cu grade of 25.12%, copper recovery of 87.63%. This index is successful in the aim of recovery copper for such mixed copper ore.
Research of Coal Desulfurization on Microwave
Authors: Wu Yue , Peng Su Qin , Ji Deng Gao , Liu Yi Zhou , Cai Yang Hui
Published: August 2013

Coal carry mass of high-sulfur coal, in order to solve the desulfurization problems, the use of microwave irradiation to coal desulfurization was studied. Exploring the temperature of microwave irradiation and raw coal moisture on the influence of coal desulfurization, the research results showed that the coal desulfurization rate could reach 25.91%. The proximate analysis of coal samples before and after by microwave radiation, the basic physical properties of coal sample after microwave irradiation didn’t change. Through XRD testing, founding that the coal sample’s mineral crystal did have little change after microwave irradiation, and chlorite and marcasite (FeS2) etc mineral crystal disappeared, and turned into emery and magnetite etc.
Research of the Complex Copper Slag Flotation Experiment
Authors: Guo Yan Hua , Dai Hui Xin , Yang Jun Long
Published: August 2013

A kind of complex Copper slag has been studied. The run-of-mine grade of copper was 0.93%. Through the research of the flotation separation test, the optimal grinding fineness (-0.074mm) was about to 75%. The optimum kind and dosage of collector was 150 g/t Y89. The dosage of sodium silicate which was the Slime dispersing agent was 1000g/t. The dosage of sodium carbonate was 800g/t.
Study on Flotation Techniques of Tailings in Dachang Mining
Authors: Mu Xiao , Chen Jian Hua , Kang Duan
Published: August 2013

For the characteristics of complex paragenetic relationship, the high oxidation rate of lead antimony zinc minerals and serious sliming, GZ was used as activator and depressor, and GC was used as collector. In this study, we recover lead, antimony and zinc from tailings in Dachang mining efficiently without using copper sulfite as activator.
Development of Novel Building Materials and Mining System Based on Improved Radio Frequency Identification Technology
Authors: Wang Yi
Published: August 2013

A detailed description of the application and performance characteristics of new energy-saving building materials, including the use of new wall material, thermal insulation material, waterproof sealing material. New building materials is different from the traditional brick, gray sand and gravel and other building materials, building materials of new varieties, instead of supporting a variety of various auxiliary materials and chemical materials. RFID tags by coupling components and chips, each tag has a unique electronic coding, attached to the object target object. The paper presents Development of Novel Building Materials and Mining system based on improved radio frequency identification technology. Experimental results show that the proposed method has high efficiency.
Research on Tension Control with Fuzzy PID Control in the Low Relaxation PC Strand Wire Based on Mechanical Automation
Authors: Li Dong Mei , Guo Lan Shen , Zhang Cheng Hu
Published: August 2013

The wire drawing quality fit and unfit quality, mainly rely on the wire drawing production line tension control is good or bad. According to the drawing process has a "lag", "nonlinear" features ,proposed uses the adaptive fuzzy PID control algorithm for ensuring a constant tension in the drawing process.Using the fuzzy control online real-time to adjust PID three controlled variable. In the MATLAB simulation, comparing with the conventional PID control to show that the fuzzy PID control of drawing tension system can maintain better constant.Keywords: Fuzzy adaptive PID, MATLAB-Simulink, Tension control, Mechanical automation
Study on Magnetic Materials with Numerical Calculation of Geoelectromagnetic Field in Middle-Low Latitude Region
Authors: Wu Wei Li
Published: August 2013

This paper expounds mechanism of the interact between the vary ionosphere currents and the Earth as a magnetic materials during magnetic storms which create the geoelectromagnetic fields on the Earths surface. Cauchy Distribution model of ionosphere currents above the middle-low latitude area is built for calculation of the fields. In order to predict and evaluate the levels of GIC flowing in technology systems,Complex Image Method (CIM) is applied to calculate geo-electric-magnetic fields on the Earths surface of the middle-low latitude. To test veracity,we compare calculation of the electromagnetic field by Complex Image Method and data measured practically. The good accuracy of CIM here is obtained. i.e,CIM can perform well in Middle-Low latitude area.
Calculation of Ionization Potential and Electron Affinity of the Optoelectronic Material Iridium (III) Metal Complexes Containing the 2-phenyl Pyridine-Type Ligands
Authors: Xia Hong Ying , Ge Guo Hua , Zhao Feng
Published: August 2013

Solid state ionization potential and electron affinity of iridium (III) metal complexes containing the 2-phenyl pyridine-type ligands was calculated using density functional theory (DFT). It is shown that the calculated results are in well agreement with the experimental values. With this approach, it is convince to obtain solid state ionization potentials and electron affinities of a range of neutral transition metal complexes.
Effect of Triethanolamine Addition in Alkaline Bath on the Electroplating Behavior, Composition and Corrosion Resistance of Zn-Ni Alloy Coatings
Authors: Long Jin Ming , Zhang Xiu , Pei He Zhong
Published: August 2013

Zn-Ni alloy coatings were electrodeposited on low carbon steel substrate using a cyanide-free alkaline bath containing tetraethylenepentamine (TEPA) and triethanolamine (TEA) as complexing agents for Ni2+cations. Effect of TEA/Ni2+molar ratio on electrodeposition behavior, micromophology, Ni content and corrosion resistance of coatings were studied by means of SEM/EDS, polarization curve and electrochemical impedance spectroscopy (EIS), respectively. It was found that the deposition potential and elecctrochemical impedance of the cathode sample during the electrodeposition was influenced by the TEA/Ni2+molar ratio (TNmr) in the bath. The deposition potential shifts negatively and the impedance rises with increasing TNmrup to 2. The nickel content in Zn-Ni deposit was varied in a range from 16.81 to 19.04 wt.%. The dependence of cathodic current efficiency and depositing velocity of the coating on TNmrof plating bath were also determined. A fine-grained and smooth-faced coating was obtained at TNmr=2, which exhibited the highest corrosion resistance in 3.5% NaCl environment.
Effect of Cl- Content, pH Value and CO2 on Electrochemical Corrosion Features of Cr15 Super Martensitic Stainless Steel
Authors: Long Jin Ming , Liu Quan Bin , Zhao Kun Yu , Yong Qi Long , Su Jie
Published: August 2013

The corrosion behavior of a Cr15 super martensitic stainless steel (Cr15 SMSS) was investigated in NaCl solutions by means of potentiodynamic polarization and electrochemical impedance spectroscopy (EIS). Effects of Cl-content, pH value and saturated CO2on corrosion were sdudied. It was found that the parameters of maintaining passivity current density (ip), the critical pitting potential (Eb) and charge transfer resistance (Rt) of Cr15 SMSS varied widely under different conditions. The corrosion resistance of Cr15 SMSS decrease with increasing Cl-concentration and lowering pH value. BothipandEbincrease for Cr15 SMSS in CO2-saturated NaCl solution, which verified that the CO2in NaCl solution can result in lower pitting sensitivity and higher uniform corrosion rate to Cr15 SMSS.
Exercise Intolerance in Individuals With Postconcussion Syndrome
Authors: Kozlowski Karl F. , Graham James , Leddy John J. , Devinney-Boymel Lee , Willer Barry S.
Published: August 2013

Context:

Little is known about exercise intolerance or the utility of an exercise evaluation in patients with postconcussion syndrome (PCS).

Objective:

To assess exercise intolerance in male and female patients with PCS.

Design:

Cross-sectional study.

Setting:

Laboratory setting.

Patients or Other Participants:

Participants included a convenience sample of 34 patients with PCS (17 males, 17 females; age = 25.9 ± 10.9 years) and 22 uninjured individuals on whom we gathered historical deidentified laboratory data (control group; 11 males, 11 females; age = 23.3 ± 6.2 years).

Main Outcome Measure(s):

Self-reported symptoms, heart rate, systolic and diastolic blood pressures (BPs), and the Borg rating of perceived exertion were measured before, during each minute of, and immediately after a graded treadmill exercise test (Balke protocol). Exercise was stopped when participants could no longer maintain the effort or reported the onset of or increase in PCS symptoms.

Results:

Exercise test duration (8.5 ± 4.4 minutes versus 17.9 ± 3.6 minutes; t51 = 1.8, P < .001), heart rate (142.8 ± 24.1 versus 175.2 ± 17.4; t54 = −5.5, P < .001), and systolic BP (142.1 ± 18.3 mm Hg versus 155.5 ± 24.5 mm Hg; t53 = 2.3, P = .02) were lower, and diastolic BP (78.4 ± 10.2 mm Hg versus 73.5 ± 11.7 mm Hg; t53 = 2.2, P = .03) was higher at test cessation in the PCS than control group. Cox regression showed the odds of a shorter exercise duration were nearly 8 times greater in the PCS than control group (hazard ratio = 7.93; 95% confidence interval = 3.39, 18.56). In the general linear models that adjusted for differences in test duration, rating of perceived exertion was the only physiologic measure to show an overall difference between groups, with the control group reporting higher ratings than the PCS group (t53 = −6.0, P < .001). Within the PCS group, systolic BP was the only measure to show a sex effect, with males showing higher pressure readings than females throughout the exercise tests (t31 = 2.8, P = .009).

Conclusions:

Patients with PCS had a symptom-limited response to exercise, and the treadmill test was a potentially useful tool to monitor the recovery from PCS.
Differences in Lateral Drop Jumps From an Unknown Height Among Individuals With Functional Ankle Instability
Authors: Rosen Adam , Swanik Charles , Thomas Stephen , Glutting Joseph , Knight Christopher , Kaminski Thomas W.
Published: August 2013

Context:

Functional ankle instability (FAI) is a debilitating condition that has been reported to occur after 20% to 50% of all ankle sprains. Landing from a jump is one common mechanism of ankle injury, yet few researchers have explored the role of visual cues and anticipatory muscle contractions, which may influence ankle stability, in lateral jumping maneuvers.

Objective:

To examine muscle-activation strategies between FAI and stable ankles under a lateral load and to evaluate the differences in muscle activation in participants with FAI and participants with stable ankles when they were unable to anticipate the onset of lateral loads during eyes-open versus eyes-closed conditions.

Design:

Case-control study.

Setting:

Controlled laboratory setting.

Patients or Other Participants:

A total of 40 people participated: 20 with FAI and 20 healthy, uninjured, sex- and age-matched persons (control group).

Intervention(s):

Participants performed a 2-legged lateral jump off a platform onto a force plate set to heights of 35 cm or 50 cm and then immediately jumped for maximal height. They performed jumps in 2 conditions (eyes open, eyes closed) and were unaware of the jump height when their eyes were closed.

Main Outcome Measure(s):

Amplitude normalized electromyographic (EMG) area (%), peak (%), and time to peak in the tibialis anterior (TA), peroneus longus (PL), and lateral gastrocnemius (LG) muscles were measured.

Results:

Regardless of the eyes-open or eyes-closed condition, participants with FAI had less preparatory TA (t158 = 2.22, P = .03) and PL (t158 = 2.09, P = .04) EMG area and TA (t158 = 2.45, P = .02) and PL (t158 = 2.17, P = .03) peak EMG than control-group participants.

Conclusions:

By removing visual cues, unanticipated lateral joint loads occurred simultaneously with decreased muscle activity, which may reduce dynamic restraint capabilities in persons with FAI. Regardless of visual impairment and jump height, participants with FAI exhibited PL and TA inhibition, which may limit talonavicular stability and intensify lateral joint surface compression and pain.
Challenges of locally manufactured vehicle supply chains in South Africa
Authors: Ambe Intaher M. , Badenhorst-Wess Johanna A.
Published: August 2013

Locally manufactured vehicles are destined (partly) for the export market and thus, global competitiveness  is  important.  This  article  explores  the  challenges  facing  supply  chains  of locally manufactured vehicles in South Africa. The automotive industry is perceived to be the most advanced in supply chain management practices in South Africa. It has embraced technology and management practices that have transformed the manufacturing environment by using cutting-edge design and visualisation tools. However, the industry has fragilities and faces new and emerging supply chain challenges. A survey research design was employed and  the  data  was  collected  through  face-to-face  semi-structured  interview  questionnaires based on the purposive sampling technique. Data analysis and interpretation was based on descriptive  statistics  using  SPSS  software.  The  findings  revealed  that  there  are  challenges hindering  best  supply  chain  practices  of  local  vehicle  manufacturers.  The  research  also revealed that there is a perceived difference in supply chain challenges between the different manufacturers of different origins in South Africa. Asian manufacturers felt much stronger about the adequacy of their information systems compared to the European manufacturers. Asian  manufacturers  tended  to  agree  more  than  their  European  counterparts  that  labour problems were a challenge. European manufacturers, on the other hand, tended to agree more that rail transport is unreliable. This article contributes to the body of knowledge on supply chain practices in South Africa.
A revised check-list of birds in the Kalahari Gemsbok National Park
Authors: Mills M. G. L.
Published: August 2013

A more complete list of the birds in the Kalahari Gemsbok National Park is given, including the results of three and a half years of observations. A total of 214 species have now been identified for the Park, among which 75 are resident throughout the year, 37 are migrants, 14 are nomads and 88 are vagrants.
Growth and development of the impala Aepyceros melampus
Authors: Fairall N. , Braack H. H.
Published: August 2013

Growth and development of the prenatal impala has been described by Fairall (1969) and Roettcher, Hoffman and Kayanja (1970) while weights and measurements of the mature animal have been reported by Sachs (1967) and Talbot and McCulloch (1965). Child (1964) has investigated growth in this species. This paper serves as a baseline for comparison of future changes in morphology of the species, as the animals were all obtained at the beginning of the culling programme.
Reproduction in the zebra mare Equus burchelli antiquorum from the Kruger National Park
Authors: Smuts G. L.
Published: August 2013

Reproductive characteristics of Burchell's zebra mares are described using data collected from captive and free ranging animals and the reproductive tracts of 310 mares shot during a game cropping campaign. The pubertal interval in zebra mares ranges from age 16 to 22 months, succesful mating occurring for the first time at 23 months of age. Full reproductive capacity is attained at three years. Zebra mares are seasonally polyoestrous, with an average of 85 of all mating and foaling occurring during the wet summer months (October to March).
Poetic Vignettes about Life
Authors: Branch Robin Gallaher
Published: August 2013

No abstract availbale.
Esophagobronchial fistulae: Diagnosis by MDCT with oral contrast swallow examination of a benign and a malignant cause
Authors: Hegde Rahul G , Kalekar Tushar M , Gajbhiye Meenakshi I , Bandgar Amol S , Pawar Shephali S , Khadse Gopal J
Published: August 2013

We report two cases of esophagobronchial fistulae diagnosed by Multi-detector computed tomography (MDCT) oral contrast swallow examination. It is helpful to supplement the CT study with an oral contrast swallow as it aids in confirmation of a suspected fistula and also demonstrates the fistula tract better. We present the clinical details and the imaging findings on MDCT of two cases of esophagobronchial fistulae - one secondary to chronic chest tuberculosis and the other secondary to a squamous cell carcinoma of the upper esophagus - followed by discussion of the etiology, pathogenesis, and imaging of these fistulae.
Role of radiofrequency ablation in unresectable hepatocellular carcinoma: An Indian experience
Authors: Kalra Naveen , Kang Mandeep , Bhatia Anmol , Duseja Ajay K , Dhiman Radha K , Arya Virendra K , Rajwanshi Arvind , Chawla Yogesh K , Khandelwal Niranjan
Published: August 2013

Aims: To evaluate the role of radiofrequency ablation (RFA) as an ablative technique in patients with unresectable hepatocellular carcinoma (HCC). Settings and Design: A tertiary care center, prospective study. Materials and Methods: The subjects comprised 31 patients (30 males, one female; age range 32-75 years) with HCC (41 lesions) who were treated with image-guided RFA. The follow-up period ranged from 3 months to 6 years, and included a multiphasic computed tomography (CT) at 1, 3 and 6 months post-RFA, and every 6 months thereafter. Patient outcome was evaluated and the tumor recurrence, survival and complications were assessed. Statistical Analysis Used: Discrete categorical data were presented as n (%) and continuous data as mean ± SD. Pearson correlation coefficient was used to determine the relationship between the different variables. Kaplan-Meier survival curve and Log-rank test were used to test the significance of difference between the survival time of the different groups. Results: The ablation success rate was 80.5% (33/41 HCC lesions). 12.2% (5/41) of the lesions were managed with repeat RFA due to tumor residue. 4.9% (2/41) of the lesions were managed with repeated RFA and transarterial chemoembolization. Eight patients had tumor recurrence (five patients (16.1%) had local recurrence and three patients (9.6%) had distant recurrence). Eleven patients died within 3.5-20 months post-RFA. The survival rate at 1 year in patients who completed at least 1 year of follow-up was 63.3%. There was one major complication (1/31, 3.2%) in a patient with a subcapsular lesion and ascites. This patient developed hemoperitoneum in the immediate postprocedure period and was managed with endovascular treatment. She, however, had hepatic decompensation and died 48 h post-RFA. Conclusion: RFA is an effective and safe treatment for small unresectable HCC.
Projected effect of 2000–2050 changes in climate and emissions on aerosol levels in China and associated transboundary transport
Authors: Jiang H. , Liao H. , Pye H. O. T. , Wu S. , Mickley L. J. , Seinfeld J. H. , Zhang X. Y.
Published: August 2013

Abstract. We investigate projected 2000–2050 changes in concentrations of aerosols in China and the associated transboundary aerosol transport by using the chemical transport model GEOS-Chem driven by the Goddard Institute for Space Studies (GISS) general circulation model (GCM) 3 at 4° × 5° resolution. Future changes in climate and emissions projected by the IPCC A1B scenario are imposed separately and together through sensitivity simulations. Accounting for sulfate, nitrate, ammonium, black carbon (BC), and organic carbon (OC) aerosols, concentrations of individual aerosol species change by −1.5 to +0.8 μg m−3, and PM2.5 levels are projected to change by about 10–20% in eastern China as a result of 2000–2050 change in climate alone. With future changes in anthropogenic emissions alone, concentrations of sulfate, BC, and OC are simulated to decrease because of assumed reductions in emissions, and those of nitrate are predicted to increase because of higher NOx emissions combined with decreases in sulfate. The net result is a predicted reduction of seasonal mean PM2.5 concentrations in eastern China by 1–8 μg m−3 (or 10–40%) over 2000–2050. It is noted that current emission inventories for BC and OC over China are judged to be inadequate at present. Transboundary fluxes of different aerosol species show different sensitivities to future changes in climate and emissions. The annual outflow of PM2.5 from eastern China to the western Pacific is estimated to change by −7.0%, −0.7%, and −9.0% over 2000–2050 owing to climate change alone, changes in emissions alone, and changes in both climate and emissions, respectively. The fluxes of nitrate and ammonium aerosols from Europe and Central Asia into western China increase over 2000–2050 in response to projected changes in emissions, leading to a 10.5% increase in annual inflow of PM2.5 to western China with future changes in both emissions and climate. Fluxes of BC and OC from South Asia to China in spring contribute a large fraction of the annual inflow of PM2.5. The annual inflow of PM2.5 from South Asia and Southeast Asia to China is estimated to change by −8%, +281%, and +227% over 2000–2050 owing to climate change alone, changes in emissions alone, and changes in both climate and emissions, respectively. While the 4° × 5° spatial resolution is a limitation of the present study, the direction of predicted changes in aerosol levels and transboundary fluxes still provides valuable insight into future air quality.
Short-term cropland responses to temperature extreme events during late winter
Authors: De Simon G. , Alberti G. , Delle Vedove G. , Peressotti A. , Zaldei A. , Miglietta F.
Published: August 2013

Abstract. In recent years, several studies have focused on terrestrial ecosystem response to extreme events. Most of this research has been conducted in natural ecosystems, but few have considered agroecosystems. In this study, we investigated the impact of a manipulated warmer or cooler late winter/early spring on the carbon budget and final harvest of a soybean crop (Glycine max (L.) Merr.). Soil temperature was altered by manipulating soil albedo by covering the soil surface with a layer of inert silica gravel. We tested three treatments – cooling (Co), warming (W), mix (M) – and control (C). An automated system continuously measured soil heterotrophic respiration (Rh), soil temperature profiles, and soil water content across the entire year in each plot. Phenological phases were periodically assessed and final harvest was measured in each plot. Results showed that treatments had only a transient effect on daily Rh rates, which did not result in a total annual carbon budget significantly different from control, even though cooling showed a significant reduction in final harvest. We also observed anticipation in emergence in both W and M treatments and a delay in emergence for Co. Moreover, plant density and growth increased in W and M and decreased in Co. In conclusion, from the results of our experiment we can assert that an increase in the frequency of both heat and cold waves is unlikely to have large effects on the overall annual carbon balance of irrigated croplands.
Petrophysical characterization of the lacustrine sediment succession drilled in Lake El'gygytgyn, Far East Russian Arctic
Authors: Gebhardt A. C. , Francke A. , Kück J. , Sauerbrey M. , Niessen F. , Wennrich V. , Melles M.
Published: August 2013

Abstract. Seismic profiles of Far East Russian Lake El'gygytgyn, formed by a meteorite impact some 3.6 million years ago, show a stratified sediment succession that can be separated into subunits Ia and Ib at approximately 167 m below lake floor (=~3.17 Ma). The upper (Ia) is well-stratified, while the lower is acoustically more massive and discontinuous. The sediments are intercalated with frequent mass movement deposits mainly in the proximal areas, while the distal region is almost free of such deposits at least in the upper part. In spring 2009, a long core drilled in the lake center within the framework of the International Continental Scientific Drilling Program (ICDP) penetrated the entire lacustrine sediment succession down to ~320 m below lake floor and about 200 m farther into the meteorite-impact-related bedrock. Downhole logging data down to 390 m below lake floor show that the bedrock and the lacustrine part differ significantly in their petrophysical characteristics. The contact between the bedrock and the lacustrine sediments is not abrupt, but rather transitional with a variable mixture of impact-altered bedrock clasts in a lacustrine matrix. Physical and chemical proxies measured on the cores can be used to divide the lacustrine part into five different statistical clusters. These can be plotted in a redox-condition vs. input-type diagram, with total organic carbon content and magnetic susceptibility values indicating anoxic or oxic conditions and with the Si / Ti ratio representing more clastic or more biogenic input. Plotting the clusters in this diagram allows identifying clusters that represent glacial phases (cluster I), super interglacials (cluster II), and interglacial phases (clusters III and IV).
Analyzing the effects of geological and parameter uncertainty on prediction of groundwater head and travel time
Authors: He X. , Sonnenborg T. O. , Jørgensen F. , Høyer A.-S. , Møller R. R. , Jensen K. H.
Published: August 2013

Abstract. Uncertainty of groundwater model predictions has in the past mostly been related to uncertainty in the hydraulic parameters, whereas uncertainty in the geological structure has not been considered to the same extent. Recent developments in theoretical methods for quantifying geological uncertainty have made it possible to consider this factor in groundwater modeling. In this study we have applied the multiple-point geostatistical method (MPS) integrated in the Stanford Geostatistical Modeling Software (SGeMS) for exploring the impact of geological uncertainty on groundwater flow patterns for a site in Denmark. Realizations from the geostatistical model were used as input to a groundwater model developed from Modular three-dimensional finite-difference ground-water model (MODFLOW) within the Groundwater Modeling System (GMS) modeling environment. The uncertainty analysis was carried out in three scenarios involving simulation of groundwater head distribution and travel time. The first scenario implied 100 stochastic geological models all assigning the same hydraulic parameters for the same geological units. In the second scenario the same 100 geological models were subjected to model optimization, where the hydraulic parameters for each of them were estimated by calibration against observations of hydraulic head and stream discharge. In the third scenario each geological model was run with 216 randomized sets of parameters. The analysis documented that the uncertainty on the conceptual geological model was as significant as the uncertainty related to the embedded hydraulic parameters.
Hydrological models are mediating models
Authors: Babel L. V. , Karssenberg D.
Published: August 2013

Abstract. Despite the increasing role of models in hydrological research and decision-making processes, only few accounts of the nature and function of models exist in hydrology. Earlier considerations have traditionally been conducted while making a clear distinction between physically-based and conceptual models. A new philosophical account, primarily based on the fields of physics and economics, transcends classes of models and scientific disciplines by considering models as "mediators" between theory and observations. The core of this approach lies in identifying models as (1) being only partially dependent on theory and observations, (2) integrating non-deductive elements in their construction, and (3) carrying the role of instruments of scientific enquiry about both theory and the world. The applicability of this approach to hydrology is evaluated in the present article. Three widely used hydrological models, each showing a different degree of apparent physicality, are confronted to the main characteristics of the "mediating models" concept. We argue that irrespective of their kind, hydrological models depend on both theory and observations, rather than merely on one of these two domains. Their construction is additionally involving a large number of miscellaneous, external ingredients, such as past experiences, model objectives, knowledge and preferences of the modeller, as well as hardware and software resources. We show that hydrological models convey the role of instruments in scientific practice by mediating between theory and the world. It results from these considerations that the traditional distinction between physically-based and conceptual models is necessarily too simplistic and refers at best to the stage at which theory and observations are steering model construction. The large variety of ingredients involved in model construction would deserve closer attention, for being rarely explicitly presented in peer-reviewed literature. We believe that devoting more importance to identifying and communicating on the many factors involved in model development might increase transparency of model building.
AEROSOL VARIABILITY OBSERVED WITH RPAS
Authors: Altstädter B. , Lampert A. , Scholtz A. , Bange J. , Platis A. , Hermann M. , Wehner B.
Published: August 2013

Abstract. To observe the origin, vertical and horizontal distribution and variability of aerosol particles, and especially ultrafine particles recently formed, we plan to employ the remotely piloted aircraft system (RPAS) Carolo-P360 "ALADINA" of TU Braunschweig. The goal of the presented project is to investigate the vertical and horizontal distribution, transport and small-scale variability of aerosol particles in the atmospheric boundary layer using RPAS. Two additional RPAS of type MASC of Tübingen University equipped with turbulence instrumentation add the opportunity to study the interaction of the aerosol concentration with turbulent transport and exchange processes of the surface and the atmosphere. The combination of different flight patterns of the three RPAS allows new insights in atmospheric boundary layer processes. Currently, the different aerosol sensors are miniaturized at the Leibniz Institute for Tropospheric Research, Leipzig and together with the TU Braunschweig adapted to fit into the RPAS. Moreover, an additional meteorological payload for measuring temperature, humidity and turbulence properties is constructed by Tübingen University. Two condensation particle counters determine the total aerosol number with a different lower detection threshold in order to investigate the horizontal and vertical aerosol variability and new particle formation (aerosol particles of some nm diameter). Further the aerosol size distribution in the range from about 0.300 to ~5 μm is given by an optical particle counter.
OMNIDIRECTIONAL PERCEPTION FOR LIGHTWEIGHT UAVS USING A CONTINUOUSLY ROTATING 3D LASER SCANNER
Authors: Droeschel D. , Schreiber M. , Behnke S.
Published: August 2013

Abstract. Many popular unmanned aerial vehicles (UAV) are restricted in their size and weight, making the design of sensory systems for these robots challenging. We designed a small and lightweight continuously rotating 3D laser scanner – allowing for environment perception in a range of 30 m in almost all directions. This sensor it well suited for applications such as 3D obstacle detection, 6D motion estimation, localization, and mapping. We aggregate the distance measurements in a robot-centric grid-based map. To estimate the motion of our multicopter, we register 3D laser scans towards this local map. In experiments, we compare the laser-based ego-motion estimate with ground-truth from a motion capture system. Overall, we can build an accurate 3D obstacle map and can estimate the vehicle's trajectory by 3D scan registration.
HIGH-RESOLUTION MULTISENSOR INFRASTRUCTURE INSPECTION WITH UNMANNED AIRCRAFT SYSTEMS
Authors: Eschmann C. , Kuo C.-M. , Kuo C.-H. , Boller C.
Published: August 2013

Abstract. This paper reports on the investigations made at Fraunhofer Institute for Non-Destructive Testing (IZFP) where different rotary wing micro UAS have been used to scan infrastructures including bridges and monuments at high resolutions for remote damage assessment and monitoring purposes. The aerial pictures taken at high speed and frequency have then been stitched together to obtain full 2D and 3D building reconstructions at a resolution allowing damages and cracking to be observed still in the millimeter range. With these ultra hi-res building reconstruction models a specific data base could be created for each object in order to provide extensive information for long term evaluation and life cycle management. The UAS also have been equipped with sensors for damage size estimation, which combined with an image processing software developed to allow automatic cracking pattern recognition could be used for further analysis.
REHABILITATION CLOSURE CRITERIA ASSESSMENT USING HIGH RESOLUTION PHOTOGRAMMETRICALLY DERIVED SURFACE MODELS
Authors: Fletcher A. T. , Erskine P. D.
Published: August 2013

Abstract. Relinquishment of mined land is unlikely to occur without compelling evidence that post mine landforms have a sustainable vegetation cover and represent a minimal liability to subsequent land users. Gully and rill erosion result in unstable landforms create unsafe landscapes for commonly targeted post mine land uses, such as grazing. The photogrammetric products of two small Unmanned Aerial Vehicle (UAV) platforms were compared as a means of delineating erosion gullies and comparing vegetation in rehabilitation at an open cut coal mine in the Bowen Basin, Queensland. Erosion gullies were clearly visible in both UAV products at 5 cm resolution; however, target illumination and photogrammetric processing methods largely determined the ability to identify erosion from surface models. Individual tree canopies were clearly visible in both products, as were phenological traits such as leaf flushing and flowering. The high spatial resolution resulted in unreliable detection of tree crowns in both processing methods.
DESIGN OF MWIR CONTINUOUS ZOOM WITH LIGHT WEIGHT
Authors: Ge J. J. , Qin Y. , Deng D. B.
Published: August 2013

Abstract. A thermal imaging continuous zoom system is developed with light weight for airborne optoelectronic detection and tracking apparatus. The continuous zoom system provides 4× zoom range from the focal of 37.5 mm to 150 mm. Based on the cool 640 × 512 detector with staring focal plane array (FPA), an optical system of middle infrared continuous zoom system is designed for airborne optoelectronic detection and tracking apparatus. The system is composed of a zoom system, a secondary imaging system and two reflectors. In order to improving the system performance, the whole system is adding four aspheric surfaces. The design results prove that the system worked at 3.7–4.8 μm has achieved the zoom of 37.5–150 mm, large zoom ratio of 4× and F number of 4, which can obtain the cold shield efficiency of 100% and the MTF more than 0.4 at the spatial frequency of 32 lp/mm closing to the diffraction limit. The overall lens length is 280 mm and the weight is 197 g. The optical system has the advantages of small volume, high image quality and simple structure.