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We introduce an edge-based procedural texture (EBPT), a procedural model for semi-stochastic texture generation. EBPT quickly generates large textures from a small input image. EBPT focuses on edges as the visually salient features extracted from the input image and organizes into groups with clearly established spatial properties. EBPT allows the users to interactively or automatically design new textures by utilizing the edge groups. The output texture can be significantly larger than the input, and EBPT does not need multiple textures to mimic the input. EBPT-based texture synthesis consists of two major steps, input analysis and texture synthesis. The input analysis stage extracts edges, builds the edge groups, and stores procedural properties. The texture synthesis stage distributes edge groups with affine transformation. This step can be done interactively or automatically using the procedural model. Then, it generates the output using edge group-based seamless image cloning. We demonstrate our method on various semi-stochastic inputs. With just a few input parameters defining the final structure, our method can analyze the input size of $$512\times {512}$$ in 0.7 s and synthesize the output texture of $$2048\times {2048}$$ pixels in 0.5 s.

Objective The aim of this study was to find ways of bridging the gap in opinions concerning health technology assessment (HTA) in reimbursement submission between manufacturers and payers to avoid access delays for patients of vital medicines such as oncology drugs. This was done by investigating differences and similarities of opinion among key stakeholders in Australia. Methods The survey comprised of nine sections: background demographics, general statements on HTA, clinical claim, extrapolations, quality of life, costs and health resource utilization, agreements, decision making, and capability/capacity. Responses to each question were summarized using descriptive statistics and comparisons were made using chi-square statistics. Results There were ninety-seven respondents in total, thirty-seven from the public sector (academia/government) and sixty from the private sector (industry/consultancies). Private and public sector respondents had similar views on clinical claims. They were divided when it came to extrapolation of survival data and costs and health resource utilization. However, they generally agreed that rebates are useful, outcomes-based agreements are difficult to implement, managed entry schemes are required when data are limited, and willingness to pay is higher in cancer compared to other therapeutic areas. They also agreed that training mostly takes place through on the job training and that guideline updates were a least favored opportunity for continued training. Conclusions Private sector respondents favor methods that reduce the incremental cost-effectiveness ratio when compared to the public sector respondents. There still exist a number of challenges for HTA in oncology and many research opportunities as a result of this study.

Fish biomass and stock assessment are estimated from acoustic volume backscattering strengths (Sv) obtained from various hydroacoustic equipment. Although sound attenuation due to fish schools and water influences the Sv value, only attenuation from water is considered during the acoustic data process. For these reasons, it is necessary to understand the characteristics of sound attenuation by fish. Unfortunately, little is known about sound attenuation from fish. In the present study, the attenuation from one to four fish specimens was precisely measured during ex situ experiments in a water tank. The scientific echo sounder of a split-beam 200 kHz transducer and a miniature hydrophone were used for the attenuation measurements. Results show that the maximum attenuation coefficient (α) was approximately 25 dB/cm when the 4 multiple fishes had high fish heights. The relationship between the attenuation coefficient (α200kHz) and the total fish height (Htotal) was approximately α200kHz=0.54∗Htotal±0.06(r2=0.72). This work describes the sound attenuation characteristics to provide basic information for the compensation of Sv from fish schools or layers.

Aluminum monoxide (AlO) and a nonstoichiometric alumina (n-alumina) with its chemical composition similar to that of AlO were proposed theoretically for a promising low-loss plasmonic material. However, they were rarely studied due to the high thermodynamic instability. Recently, n-aluminas with their O/Al atomic ratios close to 1 were found to form on Al nanospheres synthesized by electrical explosion. Although a new bulk plasmon resonance was observed below the excitonic transition energy from the n-aluminas, no investigation into surface plasmon resonance – the key component for plasmonics - was conducted yet. Here I report on surface plasmons of the n-aluminas discovered by spatially-resolved electron energy loss spectroscopy. Energy loss spectra collected from local spots of the n-aluminas are analyzed to reveal that there are two types of n-aluminas; one with two surface plasmons (n-alumina A) and the other with one surface plasmon (n-alumina B). Remarkably, the oscillator strengths of the novel surface plasmons are as high as that of surface plasmon of Al. The electronic band structure proposed for the n-alumina A shows a lossless energy zone. Consequently, current study demonstrates that the n-aluminas have the potential as a new low-loss plasmonic material.

Globally, harmful algal blooms (HABs) caused by marine phytoplankton pose a significant threat to human health and result in enormous economic loss. Many strategies have been implemented for their detection, management, and control. One such instrument is the red-tide acoustic sensing system (RASS) which utilizes a backscattered acoustic signal to detect microalgal cells in the water column, proving to be a cheap and easy tool for the HABs detection. In the current study, five RASSs were deployed at fish farms located in HAB-occurring areas of South Korea during the summer of 2018, and their performance examined for the HABs detection. From 26 July to 6 August 2018, the dinoflagellate Cochlodinium polykrikoides was the most abundant HAB species across all locations. A standard curve between the relative received level (RRL) of acoustic intensity as measured by RASS and cell densities of HAB species was constructed (R2 = 0.846) and was successfully applied to quantify the HAB cell density. The RRL values noticeably increased from July 25, 2018 and decreased from August 1. The RRL values corresponding to warning level of HABs (≥ 100 cells mL−1) were not measured after August 5. The highest 22 RRL was recorded on July 29, which corresponded to 2,782 cells mL−1. To evaluate the efficacy and accuracy of the RASS, a significant correlation (R2 = 0.997) between HAB cell abundance and backscattered acoustic signals was confirmed. Results from our study show that the RASS can produce accurate, real-time bloom data, providing significant advantages for the warning of HABs.

Vespid wasps (Vespa spp.) are the most noxious pests on apiculture, resulting in significant economic losses. Early monitoring and management are the first step to prevent the damages from vespid wasps. In this study, the acoustic signals from wasps and honey bees were measured by a microphone with a preamplifier and an analog-digital converter. In frequency analysis of the acoustic signals from wasps and honey bees, there were differences between the two species. While the fundamental frequency of the wasps was analyzed to be about 100 Hz with the strong harmonic frequencies, that of the honey bees was about 200~250 Hz. The 2nd harmonic signals from wasp were strongest while the fundamental ones from honey bees were. These different sound features generated by wasps or honey bees might be applied to develop the early monitoring system of the incursion of wasps to the apiary.

Harmful algal blooms (HABs), caused by the overgrowth of certain phytoplankton species, have negative effects on marine environments and coastal fisheries. In addition to cell-counting methods using phytoplankton nets, a hydroacoustic technique based on acoustic backscattering has been proposed for the detection of phytoplankton blooms. However, little is known of the acoustic properties of HAB species. In this study, as essential data to support this technique, we measured the acoustic properties of two HAB species, Akashiwo sanguinea and Alexandrium affine, which occur in the South Sea off the coast of Korea. Due to the small size of the target, we used ultrasound for the measurements. Experiments were conducted under laboratory and field conditions. In the laboratory experiment, the acoustic signal re]from each species was directly proportional to the cell abundance. We derived a relationship between the cell abundance and acoustic signal re]for each species. The measured signals were compared to predictions of a fluid sphere scattering model. When A. sanguinea blooms appeared at an abundance greater than 3 500 cells/mL, the acoustic signals varied with cell abundance, showing a good correlation. These results confirm that acoustic measurements can be used to detect HAB species.

It has recently been suggested that the extraordinary strain hardening rate in Fe-16Mn-10Al-0.86C-5Ni high specific strength steel [1] is due to the high back stresses arising from the strain incompatibility between austenite matrix and B2-ordered intermetallic second phase [2]. I argue here that the alloy matrix chemistry, particularly short-range ordering of constituent atoms, could be the intrinsic factor that affects the deformation and strain hardening, rather than the stress-strain partitioning caused by the microstructural heterogeneity.

With the growing demand of air traffic, it becomes more important and critical than ever to develop advanced techniques to control and monitor air traffic in terms of safety and efficiency. Especially, trajectory prediction can play a significant role on the improvement of the safety and efficiency because predicted trajectory information is used for air traffic management such as conflict detection and resolution, sequencing and scheduling. In this work, we propose a new framework by integratingthe two methods, called hybrid data-driven and physics-based trajectory prediction. The proposed algorithm is applied to real air traffic surveillance data to demonstrate its performance.

Energy consumption in the industrial sector can be significantly reduced by improving heat transfer rates in heat exchanger circuits, pool boiling, metal cutting industries, etc. Numerous energy-related issues can be overcome to a large extent by improving heat flow properties by utilizing nanofluids. The present contribution reviews the improvement in thermophysical properties of metal oxide-based nanofluids. Key parameters affecting the thermophysical properties of nanofluids, such as particle volume fraction, temperature, particle size and various stabilizers, were reviewed. The importance of DLVO theory and zeta potential to control the electrostatic repulsion and pH values of nanofluids for stable nanofluid formulations were discussed. It has been observed that classical theories of thermal conductivity and viscosity cannot predict exact values for a wide range of variables. Therefore, various extensive correlations have been introduced to predict the thermophysical properties of nanofluids. In these correlations, individual dependent variables such as particle size, temperature, nanofluid layer thickness, and Brownian velocity of nanoparticles, etc. were considered for more accurate prediction. The heat transfer efficiencies of nanofluids to base fluids in the laminar and turbulent regimes have been discussed using various figures of merits. Finally, the scope of industrial applications of metal oxide-based nanofluids and future research opportunities have been discussed.

This study was aimed to evaluate the relationship between the concentration and dilution factor (ratio) using the Air Dilution Olfactory Method, which is suggested in the Standard Method of Odor Compounds, by measuring dilution factor for m-xylene, toluene, methyl ethyl ketone, methyl isobutyl ketone, and butyl acetate. For the measurement, 18 panelists were selected by several criteria through panel test. Panelists chosen for their closely similar sensitivities provide more reproducible values. The estimation showed that the correlation of the concentration with dilution factor for the 5 compounds including the m-xylene, toluene, methyl ethyl ketone, methyl isobutyl ketone, and butyl acetate can be reasonably expressed by the equation log C = AflogD + F (Af : material costant, F : constant). The result of this study is suggested to be used as a base data for research on measures to improve the regulation standards for complex odor concentration on site boundary in operation, as well as a correlation between the concentration and dilution factor for the designated foul odor substances, and their characteristics.

The overgrowth of phytoplankton leads to negative effects such as harmful algal blooms (HABs, also called red tides) in marine environments. The HAB species Cochlodinium polykrikoides (C. polykrikoides) appears frequently in Korea during summer. In this study, we developed a real-time acoustic detection and remote-control system to detect red tides using an ultrasonic digital sensor. In the laboratory, the acoustic signals increased as the number of cells increased. At the same time, for field application, we deployed the system near the southern coast of Korea, where red tides frequently occurred in summer seasons 2013–2015. The system developed here detected red tides in situ, with a good correlation between the acoustic signals and C. polykrikoides populations. These results suggest that it may be useful for early detection of red tides.

The over-growth of phytoplankton causes harmful algal blooms (HABs) in marine ecological environments. Mobility measurement is important in understanding the action of HABs. In this study, the mobility of Amphidinium carterae Hulburt (A. carterae) was investigated using high-frequency ultrasound in the laboratory. Mobility in response to light was illustrated with M-mode images reconstructed from echoed signals. This study suggests that mobility of the swimming speed of A. carterae in response to light can be measured and calculated with M-mode images through high-frequency ultrasound. This finding may be helpful in understanding the fundamental behavior of HABs.

The propagation of sound waves through sea water is affected by fish schools, which act as obstacles scattering and attenuating incident sound waves, resulting in a loss of energy as the sound waves propagate through the water column. It is very difficult to measure the acoustic characteristics of fish schools because their sizes and positions vary significantly in natural conditions. The attenuation experiments were carried out in the artificial sea-cage at a coastal floating fish-farm of marine science station, which is located in the South Sea of Korea. The target fish species was the Japanese horse mackerel (Trachurus japonicus), which typically forms fish schools from summer to autumn in the coastal ocean. We carried out sound attenuation experiments for mid-frequency with a large number of fishes in a net cage. As a result, we observed that the signal attenuation varied with the number of individual fishes. The received level decreased as the number of individual fishes increased. This was mainly due to signal attenuation by the fishes at all frequencies. We applied statistical methods to analyze the signal attenuation by various free-swimming fish schools. Our results showed that the presence of the fish school affected the acoustic propagation by attenuating the sound waves.

Research is conducted to understand relatively unknown electronic behavior of a nanoscale Al/alumina system. This is acquired by a two-step process where characterization by electron microscopy is first performed for crystallography, followed by electron energy loss spectroscopy for electronic response from spatially inequivalent spots of Al nanoparticles with a protective surface oxide. A novel and unique plasmon from the surface oxide is found in the energy loss spectra between 5 and 6 eV other than the previously reported transitions for individual Al and Al2O3. In the current study, various properties of the new transition are sought by evaluating its dependence on crystal structure and particle size along with related physical functions. The results indicate that the novel transition has collective properties, preceded by a single-electron excitation at a slightly lower energy. Application of the Bethe f-sum rule shows that the concentration of charge carriers reaches around the Mott density by the t...

A titanium alloy implant of appropriate pore size can potentially enhance osseointegration and soft tissue integration. However, the human clinical application of such implants has not been reported. Here, we present a case of limb salvage surgery for a bone tumor using customized three-dimensional (3D)-printed Ti6Al4V radius and ulna implants. The patient presented with local recurrence at the proximal junction of the ulna and underwent a re-wide excision. Single forearm bone surgery was performed using another 3D-printed implant after resection of the recurrent tumor with an ulnar implant. Host osseointegration and soft tissue integration of the retrieved implant were quantified through histological evaluation. The total tissue integration rates of the implant at the proximal and distal bone junctions were 45.96% and 15.03%, respectively. The mesh structure enhanced bone integration by up to 10.81% in the proximal and by up to 8.91% in the distal bone junction. Furthermore, the soft tissue adhesion rates of the implant shaft were 59.50% and 50.26% in the axial and longitudinal cuts, respectively. No area was left unoccupied throughout the shaft of the implant. Overall, these results indicate that the 3D-printed Ti6Al4V titanium alloy implant with a rough surface has considerable tissue integration ability.

A scalable architecture for reducing power consumption in pipelined AC-DFA (Aho-Corasick deterministic finite automaton) tries for deep packet inspection (DPI) system is proposed. A new scheme for deciding the strides of the AC-DFA trie is devised where the stride of each pipeline is decided variably to reduce the power consumption. Scaling down the clock frequency of the rarely-used stages is applied to reduce wasted power consumption. As a result, a DPI system with the proposed schemes shows a reduction of up to 27% in power consumption, compared with the state-of-the-art DPI systems.

Surface salinity in the western sea of Jeju Island in Korea becomes low due to the inflow of the Chinese coastal waters during summer. One of the characteristics of low salinity water is the formation of a surface sound channel (SSC) due to the decrease in sound speed by salinity. However, a quantitative analysis between low salinity water and SSC has not been fully investigated yet. In this paper, a temperature-salinity (T-S) gradient diagram is introduced in order to assess SSC formation and its acoustic characteristics are also investigated through a case study of low salinity waters. Maximum angles of limiting rays were less than 4.6° and low frequency cutoffs were higher than 2.0 kHz for the SSCs formed in low salinity water. When the salinity gradients were large (0.5 psu/m), a SSC was formed more efficiently than other cases whose salinity gradients were small. On the other hand, a SSC was not formed in spite of highly positive salinity gradients when the amount of temperature gradients was negatively high enough (-0.5 °C/m). However, the acoustic energy transfer in the surface ducts was dependent on frequency and position of source.

In case of any coastal ocean near the mouth of huge rivers, low salinity water can be formed due to its large amount of freshwater discharge. For the acoustic analysis on the low salinity environment, some oceanographic data of the East China Sea and the Atlantic Ocean were collected through KODC (Korea Oceanographic Data Center) and NODC (National Oceanographic Data Center) online service. In this paper, the T-S gradient diagram is introduced to show a relation between the gradients of temperature and salinity in view of acoustic surface channel formation. Existence of haline channel, quantitative contribution of gradients of salinity and temperature, effectiveness of the channel formation can be known by the T-S gradient diagram. After applying the collected data into the diagram, tropical regions of the Atlantic Ocean show strong haline channel due to its nearly invariant temperature and drastic change of salinity with depth. The averaged transmission loss in the channel is about 5.7 ~ 7.5 dB less than that out of the channel by the results of acoustic propagation model (RAM: Range independent Acoustic Model). On the other hand, the East China Sea and temperate region of the Atlantic ocean have weaker haline channel with less difference of the averaged transmission loss between in and out of the channel as 3.2 ~ 6.0 dB. Although data samples used in this study have limitation to represent the general physical structures of the three ocean regions, the T-S gradient diagram is shown to be useful and acoustic field affected by low salinity environment is investigated in this study.

Although steel has been the workhorse of the automotive industry since the 1920s, the share by weight of steel and iron in an average light vehicle is now gradually decreasing, from 68.1 per cent in 1995 to 60.1 per cent in 2011 (refs 1, 2). This has been driven by the low strength-to-weight ratio (specific strength) of iron and steel, and the desire to improve such mechanical properties with other materials. Recently, high-aluminium low-density steels have been actively studied as a means of increasing the specific strength of an alloy by reducing its density. But with increasing aluminium content a problem is encountered: brittle intermetallic compounds can form in the resulting alloys, leading to poor ductility. Here we show that an FeAl-type brittle but hard intermetallic compound (B2) can be effectively used as a strengthening second phase in high-aluminium low-density steel, while alleviating its harmful effect on ductility by controlling its morphology and dispersion. The specific tensile strength and ductility of the developed steel improve on those of the lightest and strongest metallic materials known, titanium alloys. We found that alloying of nickel catalyses the precipitation of nanometre-sized B2 particles in the face-centred cubic matrix of high-aluminium low-density steel during heat treatment of cold-rolled sheet steel. Our results demonstrate how intermetallic compounds can be harnessed in the alloy design of lightweight steels for structural applications and others.

[Purpose] The purpose of this study was to identify changes in the thickness of the deep cervical flexors (DCFs) according to the degree of mouth opening (MO) in normal adults. [Subjects] The study's subjects were 50 normal adults (30 men, 20 women). [Methods] Ultrasound was used to obtain images of muscles, and the NIH ImageJ software was used to measure the thickness of each muscle. [Results] An increase in MO resulted in a corresponding increase in the thickness of the DCFs, and in isometric exercises (IEs), the thickness of the DCFs further increased during MO. [Conclusion] During MO, the thickness of the DCFs increased. This may be due to correlations between mandibular movements and DCFs. Therefore, the results are likely to be utilized as new clinical research data.

The purpose of this study is to determine the indicators and the criteria to classify types of train delays of high-speed rail in South Korea. Types of train delays have divided into the chronic delays and the knock-on delays. The Indicators based on relevance, reliability, and comparability were selected with arrival delay rate of over five minutes, median of arrival delays of preceding train and following train, knock-on delay rate of over five minutes, correlation of delay between preceding train and following train on intermediate and last stations, average train headway, average number of passengers per train, and average seat usages. Types of train delays were separated using the Ward`s hierarchical cluster analysis. The criteria for classification of train delay were presented by the Fisher`s linear discriminant. The analysis on the situational characteristics of train delays is as follows. If the train headway in last station is short, the probability of chronic delay is high. If the planned running times of train is short, the seriousness of chronic delay is high. The important causes of train delays are short headway of train, shortly planned running times, delays of preceding train, and the excessive number of passengers per train.

Soil scientists in the USA have created a large national database of written soil profile descriptions that follow a well-defined set of rules for describing soil morphological properties. Interpreting these soil descriptions is a skill that requires considerable practice and experience. While writing a soil description is straightforward, recreating a visual representation of a soil profile from a written description is very difficult. So far, there is no generalized approach for translating written or tabular soil descriptions into visual representations. We propose a novel procedural modeling approach inspired by procedural models commonly used in the field of computer graphics. Our framework takes tabular soil morphological data (i.e., soil profile descriptions) as textual input and translates it into visual features based on parametric models. These models can be used to generate two-dimensional soil profiles or to generate three-dimensional interactive models that allow rotation, scaling, and other forms of visual explorations. The procedural modeling technique enables the user to generate the soil profile visual representation with only a small amount of data. The images do not need to be stored because they are generated as needed.

PurposeThe purpose of this study was to investigate and propose the appropriate K‐mapping models as an approach to integrating key project components and technologies for the effective improvement of project performance within and across construction projects.Design/methodology/approachIn this holistic, single‐case study, one of the largest construction consulting firms in South Korea has been studied by conducting 15 semi‐structured interviews and the different loci for each of the K‐mapping components are identified and analyzed. Based on the different loci, four types of the K‐mapping model are provided and elucidated.FindingsResearch findings indicate that these four types of the K‐mapping model provide the criteria to identify the appropriate types of K‐map for construction project organizations, according to the characteristics and conditions of their own construction personnel, construction processes, and K‐transfer technologies. With the K‐mapping models, an appropriate knowledge management system (KMS) can be developed more effectively.Research limitations/implicationsFirst, as interpretivism was adopted as the research philosophy, the case study findings were subjective and qualitative to both the interviewees in the case study company and the researchers, though this study provided an important underpinning for future research on K‐mapping within construction project organizations. Second, the theory developed in this study was based on an investigation of the appropriate K‐mapping models with only a single case study. Nevertheless, this case study provided sufficient data and information to develop and propose a theory for successful K‐mapping model development within construction project organizations.Originality/valueIn the KM area, the definition, benefits, purposes, principles and types of K‐map have been already provided by many KM researchers and practitioners. However, no industry (practical)‐based K‐mapping model has been developed and proposed, especially in the construction industry. Accordingly, the originality of this study to be presented in one of the paper's conclusions: construction processes must be considered and adopted as a key component in the K‐mapping process, and the discussion of the four types of K‐map this research have generated, which significantly expands the existing literature on K‐mapping.

In simulation, perhaps the most common use of the term ‘fidelity’ refers to the faithfulness with which model behavior reflects modeled system behavior. While there have been studies of fidelity seeking absolute and quantitative measures, there is not yet a consensus on a workable fidelity metric. We propose a formal modeling framework for comparing discrete event system simulation models in terms of fidelity, using a relative fidelity indicator. Based on the framework, we consider the possibility that the higher fidelity simulation models can also be more productive, even though they are more expensive to develop and use, since they can be used to achieve multiple objectives. First, we propose a formal simulation modeling framework within which the fidelity of simulation models can be discussed. With this framework and a simple example, we then define a relative fidelity indicator that provides a systematic way of comparing the fidelity of two simulation models. The relative fidelity indicator focuses on the most important characteristics in simulation studies: the input and output interfaces and the variables used for specifying a real-world system and simulation models. It does not require any special modeling formalism for model comparison. Based on the relative fidelity indicator and simulation modeling framework, we state the optimum simulation model selection problem to achieve given simulation objectives. Under a practical assumption, we analyze the simulation model selection problem and derive properties related to simulation modeling and the fidelity of simulation models.

In order to merge complementary temporal and spatial nonlinear optical characteristics of Fullerene and carbon nanotubes, synthesis of double wall carbon nanotube–Fullerene hybrid was performed by covalently linking DWNT and C 60 by amination reaction with polyethylenimine. DWNT–Fullerene hybrids were characterized by thermogravimetric analysis, UV–vis spectroscopy and transmission electron microscopy. Optical limiting performance of DWNT–Fullerene hybrids is superior to those of Fullerenes and SWNTs at the same level (∼80%) of transmission. Whereas nonlinear scattering is an evident mechanism, reverse saturable absorption from Fullerene moieties has significant contribution. Charge transfer between the DWNT and Fullerene moieties may play an important role of optical limiting.

In this study an ionomer, an ion-containing polymer, was investigated at various degrees of neutralization and irradiated by fast electrons to see the effects on its properties by an electron-microscope-electron-spectroscopy system. It was found that electronic and chemical structures of the polymer can be changed dramatically by neutralization and irradiation. The modifications by neutralization may be attributed to reversible cross-linking and resultant vulnerability due to residual strain while those by irradiation to irreversible cross-linking and scission. The combination of neutralization and irradiation can change the chemistry of the polymer rapidly but in a controllable manner. It can also manipulate the size of the band gap and the type of interband transition along with the degree of the modifications. Since the modifications can be induced in a nanoscale area by convergent electrons the results of the current study may lead to utilizing an ionomer for nanotechnology.

A 3-dimensional double stacked 4 gigabit multilevel cell NAND flash memory device with shared bitline structure have successfully developed. The device is fabricated by 45 nm floating-gate CMOS and single-crystal Si layer stacking technologies. To support fully compatible device performance and characteristics with conventional planar device, shared bitline architecture including Si layer-dedicated decoder and Si layer-compensated control schemes are also developed. By using the architecture and the design techniques, a memory cell size of 0.0021 mum2/bit per unit feature area which is smallest cell size and 2.5 MB/s program throughput with 2 kB page size which is almost equivalent performance compared to conventional planar device are realized.

Yah1p, an [Fe 2S 2]-containing ferredoxin located in the matrix of Saccharomyces cerevisiae mitochondria, functions in the synthesis of Fe/S clusters and heme a prosthetic groups. EPR, Mossbauer spectroscopy, and electron microscopy were used to characterize the Fe that accumulates in Yah1p-depleted isolated intact mitochondria. Gal- YAH1 cells were grown in standard rich media (YPD and YPGal) under O 2 or argon atmospheres. Mitochondria were isolated anaerobically, then prepared in the as-isolated redox state, the dithionite-treated state, and the O 2-treated state. The absence of strong EPR signals from Fe/S clusters when Yah1p was depleted confirms that Yah1p is required in Fe/S cluster assembly. Yah1p-depleted mitochondria, grown with O 2 bubbling through the media, accumulated excess Fe (up to 10 mM) that was present as 2-4 nm diameter ferric nanoparticles, similar to those observed in mitochondria from yfh1Delta cells. These particles yielded a broad isotropic EPR signal centered around g = 2, characteristic of superparamagnetic relaxation. Treatment with dithionite caused Fe (3+) ions of the nanoparticles to become reduced and largely exported from the mitochondria. Fe did not accumulate in mitochondria isolated from cells grown under Ar; a significant portion of the Fe in these organelles was in the high-spin Fe (2+) state. This suggests that the O 2 used during growth of Gal- YAH1 cells is responsible, either directly or indirectly, for Fe accumulation and for oxidizing Fe (2+) --> Fe (3+) prior to aggregation. Models are proposed in which the accumulation of ferric nanoparticles is caused either by the absence of a ligand that prevents such precipitation in wild-type mitochondria or by a more oxidizing environment within the mitochondria of Yah1p-depleted cells exposed to O 2. The efficacy of reducing accumulated Fe along with chelating it should be considered as a strategy for its removal in diseases involving such accumulations.

Paste technology has progressed to a widely accepted, cost-effective backfill method, and is also used extensively in surface tailings disposal. The non-segregating nature of paste makes it a very attractive option for backfilling, and its stacking behaviour due to its low water content significantly reduces the risks associated with surface tailings dam failure. While the capital and operating costs for the preparation and transportation of paste are higher than that of hydraulic fill, there are significant benefits with respect to transportation, such as reduced pipe wear and reduced risk of pipe plugging, not to mention the benefits associated with greatly reducing the water handling issues underground. From an environmental standpoint, the benefits of paste versus hydraulic fill include the ability to place more of the fine tailings fraction underground, thereby reducing the need for surface tailings storage. Another environmental benefit is the reduced risk of downstream contamination in the case of a tailings dam failure, due to the fact that disposing of the tailings in a paste form means virtually no need for liquid containment, and therefore no means for the tailings to travel downstream. Portland cement is typically used to solidify backfill, whether paste or hydraulic. This represents a major cost in mining operations due to production and haulage costs of ordinary Portland cement. In addition, the manufacturing of cement raises environmental considerations because it produces a considerable amount of CO2 emissions. Therefore, the search for additives which allow for a reduction in the required cement content in backfill has been ongoing for decades. Acti-Gel®208 is a highly purified magnesium aluminosilicate that acts as a high performance anti-settling agent and rheology modifier used in a wide variety of water-based industrial applications. Studies have shown that as an additive in paste backfill, it results in improved strength and flow properties, such as friction loss and segregation. This paper presents the results of a study conducted by Active Minerals International LLC for a South African gold mine operation in 2013, as well as the results of a study conducted by the CanmetMINING Sudbury Laboratory for Vale Canada Ltd. in Sudbury, Ontario, Canada, in 2014. The feasibility of ActiGel®208 as a cost-effective additive for underground paste and hydraulic backfill applications was investigated through the preparation of samples to compare the strength and flowability characteristics of standard mixes to those containing different dosages of Acti-Gel®208. It was found that at a low dosage of 0.03 wt%, Acti-Gel®208 delivered enhanced performance in unconfined compressive strength tests as well as in the pilot-scale flow tests. A significant reduction in binder content could be realised with addition of Acti-Gel®208 at the gold mine operation in South Africa, as well as at the Coleman and Creighton Operations in Sudbury, Ontario, Canada. The economic benefits of such a binder reduction with respect to the Canadian operations are also discussed in this paper.

Nanometer-size iron-rich particles in carbon nanotubes have been studied by transmission electron microscopy with and without in situ and ex situ heating. Several remarkable results were found; a high temperature phase (γ-Fe) of iron stable at low temperatures and preferential presence of iron and iron carbide in carbon nanotubes. Based upon these experimental results, thermodynamics of the Fe–C phase diagram and its kinetics were used to explain the non-uniform distribution of iron and iron carbide, which also yielded a deeper insight into the formation of carbon nanotubes. Some of the results also allowed describing the role of the graphitic structure in retaining the high temperature phase (γ-Fe) of iron at low temperatures. Furthermore, methods have been demonstrated with which γ-Fe can be produced in carbon nanotubes intentionally or in a large quantity. Selected area electron diffraction patterns of iron inside nanotubes demonstrated the crystallographic relationship of the iron to the nanotube axis along with phase changes of the iron. This paper summarizes the findings and draws further conclusions on the particle shape inside multiwalled carbon nanotubes.

Crystallographic structures and orientations of nanoscale iron particles encapsulated in carbon nanotubes (CNTs) were studied with or without heat treatments at various temperatures. It was found from this study that γ-Fe with a face-centered-cubic crystal structure (known to be stable in the temperature range of 912–1394 °C for bulk iron) retains its stability in a large quantity at room temperature inside the cavities of CNTs. The relative number of γ-Fe particles was found to increase with temperature, especially with heat treatment at 1400 °C or higher. It was also found that iron particles in CNTs are oriented in specific crystallographic directions of their crystal structures along the axis of the nanotubes.

The effects of the dispersion and concentration of single walled carbon nanotube (SWNT) on the flammability of polymer/SWNT nanocomposites were investigated. The polymer matrix was poly (methyl methacrylate) (PMMA) and the SWNT were dispersed using a phase separation (‘coagulation’) method. Dispersion of SWNTs in these nanocomposites was characterized by optical microscopy on a micrometer scale. Flammability properties were measured with a cone calorimeter in air and a gasification device in a nitrogen atmosphere. In the case where the nanotubes were relatively well-dispersed, a nanotube containing network structured layer was formed without any major cracks or openings during the burning tests and covered the entire sample surface of the nanocomposite. However, nanocomposites having a poor nanotube dispersion or a low concentration of the nanotubes (0.2% by mass or less) formed numerous black discrete islands with vigorous bubbling occurring between these islands. Importantly, the peak heat release rate of the nanocomposite that formed the network layer is about a half of those, which formed the discrete islands. It is proposed that the formation of the discrete islands is due to localized accumulation of the nanotubes as a result of fluid convection accompanying bubble formation and rise of the bubbles to the surface through the molten sample layer and bursting of the bubbles at the surface. The network layer acts as a heat shield to slow the thermal degradation of PMMA.

In this study, oxidized iron particles on an amorphous carbon film were irradiated by an intensive and convergent electron beam in situ inside a transmission electron microscope. It was found that some iron particles could be fractured into several particles and also could form a graphitic film on the outer surface in a very short time by the electron beam. By the electron beam the iron particles were found to be reduced to α-Fe, γ-Fe, or Fe3C. The high temperature phase of iron (γ-Fe) was observed to be stable only when it was tightly encapsulated in a graphitic film formed during the beam irradiation. This result indicates that the high elastic modulus of graphite on the surface holds the γ-Fe phase from expanding and transforming to α-Fe (the stable phase of iron at room temperature).

Selective encapsulation of different materials or phases of a material inside a carbon nanotube leads to controlling local properties of the nanotube. We report a method of synthesizing stable γ-Fe selectively inside a carbon nanotube by transforming α-Fe through electron irradiation in situ inside a transmission electron microscope. Therefore, this method enables a single nanotube to encase both high (γ-Fe) and low (α-Fe) temperature phases of iron simultaneously. γ-Fe produced by this method may be used as a novel catalyst, and its presence inside a carbon nanotube may affect the physical properties of the nanotube, which therefore can be used to modify the nanotube.