Search

Increased opposition from environmental groups is severely restricting the operation and planning of large-scale surface mines in the world. Some projects of surface mining will have to be cancelled and downsized due to environmental issues. Under this social situation, the mining industry has started the campaign and the public relations for the importance of extracting and using coal resources in order to mitigate the protection. It has been recognized throughout the industry that planning is essential to minimize the effects of mining on the environment. Environmental management and rehabilitation are now integral parts of planning for mining.Mines have a finite life that ceases when the mineral has been fully extracted. During the life of mine, mining, especially surface mining, has the potential to have environmental effects that extend beyond the confines of the mine boundary. These include erosion with increases in sedimentation and turbidity in surrounding water courses and leaching of salts that also result in the reduction of water quality. These effects may range from minimal to quite severe and widespread, depending upon the physical and chemical properties of the overburden and reject materials, the climate and location of the mine, and its relationships with surrounding land uses. Rehabilitation of mines is aimed towards the projected future land-use of the area.This paper describes surface mining systems in Australia and then discusses the factors that should be considered in order to avoid potential environmental issues resulting from surface mining when developing a new surface mine.

Conventional highwall mining extracts coal with an auger machine or a continuous miner from exposed seams at the base of opencut or strip operations. However, under poor strata and high stress conditions, highwall mining cannot be conducted due to pillar and roof failures. In such cases, punch highwall mining is more effective than the conventional highwall mining. This paper describes conventional highwall mining and punch highwall mining systems and discusses the stability of the highwall due to punch highwall mining at opencut coal mines.

In order to understand the effects of increasing temperature and confining pressure on the fracture toughness of clay bearing rock, fracture toughness experiments were carried out at temperatures elevated from room temperature up to 200°C using single edge-notched round bar in bending (SENRBB) and semi-circular bend (SCB) specimens of Kimachi sandstone and Tage tuff. This paper describes the methodology for evaluating level 1 fracture toughness and the crack growth resistance curve. The crack growth resistance curve is shown to yield true fracture toughness even when under-sized specimens are employed. The under-sized specimens refer to those which are too small to produce valid fracture toughness value using the standard methods. The fracture toughness of Kimachi sandstone did not vary significantly with temperature up to 125°C, but above that point, it increased with temperature. SENRBB tests showed that the level 1 fracture toughness increased by approximately 40% at 200°C over its value at room temperature. The fracture toughness of sandstone and tuff was found to be significantly affected by increasing confining pressure. For example, in the arrester orientation, the fracture toughness of Kimachi sandstone increased by approximately 470% at 9 MPa confinement over its value at atmospheric pressure. A quite similar variation of fracture toughness is caused by the combined effects of temperature and confining pressure. For example, under a confining pressure of 7 MPa, the fracture toughness of sandstone decreased with temperature up to 75°C, and then increased between 75°C and 100°C.

Recently, small-diameter shallow tunnels are often constructed by using slurry pipe-jacking method. This is the sewage tunnel drivage method. This system involves the pushing or thrusting of a drivage machine through concrete pipes ahead of jacks. Chemical grout injection into the surrounding soil around the tunnel is carried out before/after the drivage and pushing processes. The purpose of the chemical grout injection is to maintain a permanent stability of the surrounding soil. However, the behavior of the chemical grout solution in the surrounding soil around the tunnel is not clarified.From these points of view, a numerical simulation model was developed in order to clarify the behavior of chemical grout solution. This model consists of a set of non-linear partial differential equations, the flow equations and the mass transport equations. The flow equation considers the effect of viscosity variation of the injected grout solution. As a chemical grouting process was analyzed by using this model, the permeation and the distribution process of the injected chemical grout solution was clearly understood.Moreover, the effectiveness of the chemical grout injection was evaluated by using non-linear FEM analysis. From this results, the relation between confining stress and Young's modules of the soil/grouted zone should be taken into consideration when the range of the grouted zone is designed.

A large amount of flyash from the coal combustion is produced. About 55% of flyash in Japan is now utilized and the remains are dumped at disposal sites; however, the life of these sites is limited. Therefore, in this study, an effort was made to analyze the lining materials by applying flyash cement as a part of its recycle and utilization. When flyash is added to Portland cement, the same kinds of oxides as those of the cement are added. As an injection component, flyash acts, in part, as a fine aggregate which has similar function to fine debris materials of slakeprone rock and, in part, as a binding component. From these points of view, in order to clarify to what degree the flyash content affects the properties of the lining materials, some different combinations of flyash, Portland cement and water were considered by means of several laboratory experiments, such as a fluidability test, unconfined compressive test, slaking index test and so on. Also, the utilization of flyash as backfilling materials in the mining engineering fields by means of laboratory testing and a numerical method was applied to analyzing the slake-prone rock slope stability when the mixtures are implemented as lining materials of the embankment.

In order to protect the safety of workers construction, as well as for environmental and cost reasons, efficient small-diameter shallow tunneling methods have recently become increasingly important in regards to outside plant engineering such as for water supplies, electricity, telecommunications and gas. The effects of the above projects in overcrowded urban areas are significant and often result in substantial impact and traffic delays associated with a loss of travel time. Clearly the solution to these utility placement problems, if the full impact of trench excavation is to be avoided, is trench less technology. In particular, for construction work near existing facilities, underground tunnels that are excavated by slurry pipe-jacking are being increasingly employed in order to avoid problems. Slurry pipe-jacking was firmly established as a special method for the non-disruptive construction of the underground pipelines of sewage systems. Pipe-jacking, in its traditional form, has occasionally been used for short railways, roads, rivers, and other projects. Basically the system involves the pushing or thrusting of a drivage machine through concrete pipes ahead of jacks. This method utilizes mud slurry that is formed around the pipes in order to stabilize the surrounding soil. Moreover, in recent years, the rectangular shape of the concrete pipe in using slurry pipe-jacking was introduced due to the effective uses of the space. Based on his reason, the rectangular shape of the concrete pipe is often adopted in Japan. From this point of view, this paper discusses the effect shapes have on the stability of surrounding soil by means of the numerical analysis. Secondly, this paper discusses the performance of the mud slurry around the drivage pipes by means of the two-dimensional Eulerian-Lagragian seepage analysis. Moreover, in slurry pipe-jacking, the performance of the mud slurry plays an important role in the pushing process. Finally, the thrusts in slurry pipe-jacking can be predicted accurately by evaluating the resistance between the mud slurry and the concrete pipes and the resistance between the soil and the pipes in the curved jacking area.

There are many sites where opencut mining operations have developed long highwalls that have been abandoned due to the economic limits of surface mining technology. Highwall mining is a technique utilized after the opencut portion of a coal seam has been mined, sometimes prior to the introduction of full-scale underground mining. In the highwall mining, the coal seam is mined by remotely operated equipment such as an auger or a continuous miner. However, a large amount of coal tends to remain isolated and undeveloped as pillars due to mining operations performed by the auger or the continuous miner. Major issues are less coal recovery and highwall instability due to pillar and roof failures of the extraction holes.Where the conventional opencut mining is difficult or impossible in a small-scale mine due to uneconomical stripping ratio, the highwall mining systems could be applied to this site. After making a small pit, the mining operation starts from the outcrop with less environmental disturbance.This paper describes highwall mining systems and their problems and also proposes new mining systems to increase the coal recovery from final highwalls with using conventional underground mining methods and equipment.

Aluminum covered with porous anodic oxide films was re-anodized in 0.5 kmolm-3-H3BO3 and 5×10-5kmolm-3-KOH solutions to examine the formation and breakdown of the oxide film.In H3BO3-solution, the pores were filled with new oxide during re-anodizing, resulting in the uniform thickening of the barrier layer until film breakdown started. The breakdown potential of the film formed by the “pore-filling” method was 200V higher at maximum than that formed by anodizing after electropolishing.In KOH solution, the pore-filling with new oxide was accompanied by local dissolution of oxide film, leading to the formation of rough interphase between oxide film and the substrate. The film breakdown potential of the film formed by the “pore-filling” was as high as that the the oxide film formed after electropolishing.Effects of the structure of porous anodic oxide films on the film breakdown potential during re-anodizing in H3BO3 solution are discussed.

Aluminum was anodized in diluted KOH solutions galvanostatically to examine the effect of KOH-concentration on the growth and breakdown of anodic oxide films. Time-variations in the anode potential, Ea, the amount of dissolved Al3+ ions, and electroluminescence intensity were measured during anodizing, and the film structure was observed by transmission electron microscopy and scanning electron microscopy.At 5×10-5 and 5×10-4M, Ea increased with time linearly at the initial stage, and the rate of increase in Ea decreased at 400V. The slow increase in Ea stopped at about 600V, and beyond the potential Ea increased at a high rate until the film breakdown started at 1600V and 1100V in 5×10-5 and 5×10-4 M solution, respectively. In both solutions, the growth of the oxide film was accompanied by the formation and growth of relatively large voids between 400V and 600V, and beyond 600V small numerous voids developed on the entire surface. The film growth can be explained by the local oxide dissolution and precipitation of hydroxide.At 5×10-3 M, Ea remained zero for the initial 1500s of anodizing, and then increased linearly with time before film breakdown started at 600V. The anodic oxide films consisted of two layers: an outer porous layer and an inner dense layer.

A bleeding examination and a flow characteristic examination of grout materials were performed to understand the fundamental characteristic of grout materials. Moreover, an injection experiment of grout materials which used a decomposed granite was conducted to understand the applicability of the analysis technique which introduced filtration theory. The results are as follows:1) When cement water ratio is large, a bleeding speed becomes slow, but the bleeding ratio becomes small.2) Plastic viscosity and yield stress become large with increase of cement water ratio. Particularly, plastic viscosity change greatly on C / W = 1 / 1.6. And as compared with yield stress, it is larger about influence on the discharge.3) Where a cement water ratio does not exceed C / W = 1 / 5, the clogging of the voids was done by a suspension custody. And where C / W = 1 / 3.5, that was done by a surface filter layer.4) The plastic viscosity measured using Brookfield viscometer is a result when some cement particles aggregate, and shows big value as compared with the theoretical relative viscosity.5) The result of injection analysis using the theoretical relative viscosity assumed that the cement particle is distributing completely is well as an experiment result in agreement. In the grout materials which flow the inside of the voids, it cleared that plastic viscosity follows the theoretical relative viscosity which the cement particles distributed.

A bleeding examination and a flow characteristic examination of grout materials were performed to understand a difference of the flow characteristic by the difference in the material mixed grout materials. Moreover, the flow characteristic of grout materials in the voids and applicability to field of injection analysis were examined. The results are as follows1) The influence of bleeding becomes the largest during a flow of W + C.2) In W + C + P + B, the bleeding is controlled by making the connection with a clay particle and the electrolyte generated from cement.3) W + C + P and W + C of 15 % or less of volume concentration can be assumed to be Newton fluid. However, W + C + P + B must be taken as Bingham fluid since yield stress changes with volume concentration a lot.4) The plastic viscosity of the grout materials which flows the inside of the voids follows the theoretical equation which Mori and Ototake (1955) introduced regardless of the kind of grout materials.5) The injection water and the injection grout materials will be flow in the laminar flow state if there is a proportional relation to the injection pressure, the discharge and Lugeon value.6) It analyzed about the stage which has the relation shown by the above 5). Consequently, the injection analysis and the field data were well in agreement, and the applicability to the field of this analysis technique was confirmed.

In order to understand the effect of elevated temperature on fracture toughness, fracture toughness experiments were carried out at increasing temperatures from room temperature to 200 °C using the single edge-notched round bar in bending (SENRBB) specimen and the semi-circular bend (SCB) specimen of Kimachi sandstone. The paper firstly describes the methodology for the evaluation of level I fracture toughness and crack growth resistance curve. Crack growth resistance curve is also shown to consider the increase of the crack growth resistance with crack growth. The experimental results showed that fracture toughness of Kimachi sandstone did not vary significantly at temperature up to 125 °C and increased with elevated temperature beyond 125 °C. The level I fracture toughness from the SENRBB testing increased by approximately 40 % at 200 °C when compared to the value at room temperature. The variation of fracture toughness can be explained in terms of thermally-induced microcracks and dehydration of interlayer water and adsorptive water included in clay material such as montmorillonite. The thermally induced microcracks, which were confirmed under microscope, lower the fracture toughness due to decrease in crack growth resistance, while the dehydration of interlayer water and adsorptive water in the rock specimen, which were confirmed by measuring weight under several temperatures, raises the fracture toughness because of increase in bonding strength between the mineral particles. Based on the strain and Young's modulus measurements under elevated temperature, it was concluded that the dehydration of interlayer and adsorptive water and the thermally induced microcracks influenced on the fracture toughness of Kimachi sandstone.

Stability of the retained goaf-side gateroad (RGSG) is influenced mainly by the movements of the roof strata near coal seam after coalface passes by. To make effective controlling technology for the stability of the RGSG, we analyze the roof structure over the RGSG to illustrate the mechanism causing the RGSG instability under different roof conditions. We then examine the dynamic evolution of the deformation and abutment stress in the rock surrounding the RGSG during coal seam mining, using the FLAC3D numerical software to reveal the instability characteristics of the RGSG under different roof conditions. Next, corresponding stability controlling technologies for the RGSGs are proposed and tested in three typical deep underground coalmines. Results show that: sink and rotation of the roof cantilever over the RGSG impose severer influence on the stability of the RGSG. The RGSG suffers disturbances three times during the coal-seam mining, and the deformation and abutment stress in the rock surrounding the RGSG increase significantly when the main roof becomes thicker and the immediate roof becomes thinner. Staged support technology involving grout cable bolts has better controlling results of the RGSG stability than that composed of conventional rock bolts, when the RGSG is beneath weak immediate roof with large thickness. Roof structure optimizing technology involving pre-split technology can improve the stability of the RGSG effectively when the RGSG is covered by hard main roof with large thickness directly.

In this paper, a series of parametric three-dimension numerical simulations were carried out to estimate the face stability and to calculate the minimum allowable slurry pressure of pipe jacking tunnel in frozen ground for the first time. In total, 5120 of simulation schemes were done with different ground temperature, diameter and cover thickness of tunnel, cohesion and friction angle of frozen soil. In order to figure out the optimal grouting pressure, 4 groups of additional simulations are computed with the uniform face support pressure of 0.5, 1.0, 1.5 and 2.0 times of horizontal stress, σH, at tunnel axis. The qualitative analysis of heading face deformation mechanism and quantitative analysis between deformation profiles and influential factors were implemented to comprehend the heading face deformation characteristics when conducting pipe jacking tunnel in frozen ground. The results show that ground temperature plays a dominant role to control the face deformation of jacking tunnel in frozen ground. And, factors of tunnel diameter and cover thickness have relatively greater influence on the deformation regulation than that of shearing parameters of frozen soil, cohesion and friction angle. Finally, the minimum allowable slurry pressure for each simulation schemes are obtained, which may be used in construction the pipe jacking tunnel in frozen ground.

Soil erosion is one of the most important problems in Indonesia coal mining reclamation area because located in tropical areas which has high average of rainfall. Severe soil erosion leads to the unsuccessful reclamation progress in the post mine surface due to impact on steep slope and limit of seedling establishment. Considering the impact of soil erosion in mining activities, Indonesian government had issued several regulations related to erosion control. Soil erodibility is one of the main factors controlling soil erosion. It will determine amount of soil loss and total sediment. Estimation of soil erodibility aims to determine the susceptibility of soil to be eroded by water. The estimation considers soil texture, percentage of organic matter, soil structure and soil permeability. This study was integration between field work to collect soil sample, soil laboratory analysis, soil erodibility analysis using erodibility equation Wischmeier and Smith (1978) and analysis to predict soil erosion/ annual total soil loss. The results show that soil erodibility in study area was calculated to range from 0.091 to 0.142 tons ha h/ha/MJ/mm and soil erodibility of the study area was categorized as very low and low. There are strong relationships between soil erodibility and soil erosion but the correlation was not fully linier due to other factors controlling soil erosion / annual total soil loss.

The technology of grouting, like the several other ground improvement methods, is in a constant state of flux, with new materials and construction techniques being developed constantly. Modern grouting began in the mining industries, concerned with seepage and strength control in mines, tunnels and shafts, then was taken up by civil engineering. In order to reduce the water flow through soil or fractured rock mass, grouting is a commonly used method and a very important method. In particular, in dam construction, grouting is the method used abundantly to ensure water-tightness and tightness. Generally, grouting in dam construction is the construction method that soil voids and crack around borehole is filled by pressurized injection of grouting material such as cement and permeability or mechanical characteristics of rock mass is improved.

Mining operation of open cut mines gives serious impacts on surrounding environment such as disturbance of the tropical rainforest, the pollution of surface and/or ground water, subsidence and erosion. Rehabilitation is one of the important and considerable topics for an environment protection under such situations. Adequate rehabilitation program will solve these environmental issues and recover the ecosystem. The basic concept of rehabilitation in open cut mines is the creation of a stable and self-sustaining land surface in post mine surface involved the creation of conditions suitable for the establishment and permanent development of a dense cover of vegetation. In usual, a lot of open cut mine keep the topsoil individually in the natural forest during soil stripping process and spread the topsoil to rehabilitation area for success of revegetation. However, there are some considerable points for dealing with topsoil in situ such as the soil properties and severe compaction by heavy equipment. Therefore, the proper topsoil management has to be considered for establishment of vegetation in post mine surface.

Acid Mine Drainage (AMD) is one of the serious problems which are caused in the mining operation. The main factors which cause the problem are H2O and O2 and sulfide minerals such as iron pyrite. Sulfide minerals are usually contained in any type of crustal structure, and there is a possibility of generation of AMD in any area. The problem may impact on the ecosystem or people in the surrounding area since the acidic water is low-pH and usually contains high level of heavy metals. Therefore, it is important to prevent the problem in mining operation. A passive treatment is low-cost and easy to maintain for dealing with AMD problems. In a passive remediation, the study on behavior of AMD generation and elution behavior of heavy metals in a laboratory is necessary before introducing it in the mine site to construct it designed for the situation. Moreover, elution behavior may be changed by management of waste rock, as a practical matter, acidic water generates due to a rough treatment of waste rock in some mine sites. Therefore, in this research, the study on the waste rock was conducted for predicting a quality of acidic water by characterizing the rock and for elucidating effects of treatment of waste rock to elution behavior of heavy metals. This paper describes the results of laboratory experiments such as a column test and a sequence extraction for predicting elution behavior of heavy metals and an occurrence of acidic water, and treatment of waste rock for effective countermeasure for dealing with acidic water for a long term is discussed.

A detailed study to propose new design support systems for underground mine was carried out in this paper. The depth was increased to develop the production in accordance with the vein.The cut and fill mining method was selected for this mine in line with the geometry of vein, topographic specifications, and annual production rates.Excavationsize, distance between stope and decline, depth, and the impact of fault governedthe induced stresses. Different depths in multiple excavations were analyzed in this study especially on decline area. The rock properties of investigated areawere defined from the field and laboratory test for each rock type. Support systems for the decline were designed based on the suggestions of the Rock Mass Rating (RMR) system and the Q system for rock mass classification. Induced stress on different levels were calculated to define Stress Reduction Factor (SRF) and applied to predict the support system by Q system. New method namely Hybrid Numerical Empirical Model was developed to support requirement analysis in cut and fill mining method. The support system requirement influenced by depth. The shotcrete will be thicker and rock bolt space more closely as increasing the depth.

In recent years, many restaurants have adopted Self-ordering systems. Conventional Self-ordering systems place tablet-type devices on tables for customers, even though such systems impose high installation costs without supporting personalized menus. They also fail to reduce food allergy incidents at restaurants. Since existing paper menus or Self-ordering systems present identical menus to all customers, individual customer information is not considered. We propose and implement a system that presents a menu using a customer information terminal which is personalized using the customer's user information. Customers can order food from it. In addition, we survey and evaluate our proposed system and show that usefulness of its superimposed display of additional menu information. We expect that additional functions will also be benefical for non-allergic holders.

The EGAT Mae Moh lignite mine is the largest open-pit coal mine in Thailand. The total geological and economical reserves of Mae Moh coal field are approximately 1,140 Mt and 825 Mt, respectively. The annual production is 12 Mton, which represents 90 % of the total coal production in Thailand, and tends to decrease gradually. In this mine, the development of underground mine from final highwall is considered after the open-pit mining operation is finished. Longwall mining is one of the common methods for extracting coal in various thickness of coal seams and is much more effective, productive and safer than any other mining methods. The productivity of longwall mining is potentially high because it is basically a continuous operation requiring fewer workers and allowing a high production rate to be sustained. Due to unfavorable geological and geotechnical conditions such as weak strata and huge final pit slopes in this mine, however, various studies on the introduction of underground mining systems have been conducted so far. Optimizing boundary and/or safety pillars and panel design for both safety and economics is a key part of planning longwall mines. This paper discribes the applicability of the longwall mining system from final highwall and its suitable design taking the slope stability into consideration by means of three-dimensional explicit finite-difference program FLAC 3D producted by ITASCA.

In modern mining industry, the blasting technique is one of the most adopted techniques for rock excavation and fragmentation due to its economical and efficient aspects. However, compared with other methods, the use of explosives in blasting is limited by law as it may have a severe impact on the surrounding environment such as vibration, noise and dust. Especially, a ground vibration induced by blasting has to be paid much attention in the mining operation as it may give an obvious impact on the surrounding facilities and buildings and In many established safe level blasting criteria, the ground vibration level is characterized by using three parameters; duration, amplitude (peak particle velocity :PPV) and frequency. Current studies on the blast-induced ground vibration focus on two parameters amplitude and frequency that suggested by USBM when the concerned subject is structure, i.e.. Hence, the control of PPV and dominant frequency are very important in order to design an appropriate blasting standard and minimize its environmental impacts.

Recently, for the concern of safety in constructions as well as for environmental and economical reasons, an efficient small-diameter shallow tunneling method has become increasingly important for outside plant engineering such as water supply, gas, electricity, telecommunications. In particular, for construction work near existing facilities, an underground tunnel excavated by the pipe-jacking is becoming increasingly popular to avoid adverse effects.Basically, the pipe-jacking system is involving the pushing or thrusting of the drivage machine through the concrete pipes ahead of jacks. The method utilizes the mud slurry that is formed around the pipes for stability of surrounding soil. However, it is not well understood the behavior of the soils and mud slurry around the pipes.From this point of view, this paper discusses the effect of mud slurry and stability of surrounding soil by means of the fundamental property tests and the laboratory tests. Moreover, this paper analyzed the performance of the behavior of mortar and mud slurry as the rehabilitation method by means of two-dimensional Eulerian-Lagragian seepage analysis.

In the present study we have experimentally investigated DRA Method (Deformation Rate Analysis Method) to understand the effect of confining pressure and stress level on the estimation of previous stress. In addition, the DRA and AE Methods were applied on the estimation of the in-situ stress from the rock cores that were obtained from Ikeshima Colliery. The following main results were obtained.(1) The previous stress can be obtained by the objective criterion that is settled for reading the laboratory data.(2) The confining pressure did not have any significant influence on the stress estimation in DRA Method.(3) DRA using the strain data in the test under a confining pressure enabled us to accurately estimate the axial stress that was previously applied under a confining pressure, even if the previous stress was very close to the uniaxial compressive strength.(4) DRA and AE Method that are carried out at a laboratory can be applied on the in-situ stress measurement method.

One-dimensional injection analysis was performed to understand the infiltration process and the filling process of grout materials into the voids of homogeneous ground. Regarding the analysis of the filling process, the material transport equation considering the filtration theory was introduced and used. Generally, a cement-based grout can be treated as a Bingham fluid characterized by plastic viscosity and yield stress. Regarding the analysis of the infiltration process, the equation of the plug flow related to the Bingham fluid inside the circular pipe was expanded and used. The results of this analysis are as follows:1) After the injection, the change of discharge by grout injection shows a rapid decline, and it becomes gradual afterward.2) As the concentration of grout thickens, the accumulated discharge of the grout material decreases and the accumulated cement amount increases conversely.

The real-time observation of a power factor will be indispensable for the maintenance and the stable voltage regulation in three-phase power distribution systems. To carry out the observation, the authors have devised and proposed an insulator built-in type of voltage-current sensor. According to their previous investigations on the sensor, it was found theoretically that a serious phase shift in the measured waveforms of the voltage and the current might occur owing to the electromagnetic interference of each phase. In the paper, they propose the compensation winding for the current sensor in the horizontal and vertical power distribution systems.

Recently, for the concern of safety in construction as well as for environmental and economical reasons, an efficient small-diameter shallow tunneling method has become increasingly important for outside plant engineering such as water supply, gas, electricity and telecommunications. In particular, for construction work near existing facilities, an underground tunnel excavated by the pipe jacking is becoming increasingly popular to avoid adverse effects. Basically, the pipe jacking system involving the pushing or thrusting of the drivage machine through concrete pipes ahead of jacks. The method utilizes the mud slurry which is formed around the pipes for stability of surrounding soil. The Japan Sewage Association proposed empirical prediction equations of the thrusts in using the pipe jacking method. However, these prediction equations are not accurate. From this point of view, the major purpose of this study is to find the way to predict the thrusts in using pipe jacking. In pipe jacking, the performance of the mud slurry plays an important role in the pushing process. The thrusts in pipe jacking can be predicted well by using the initial thrusts and the resistance between the mud slurry and concrete pipes.

Crack Projection Method has been proposed for the crack opening measurement of rocks, using the 3-dimensional data of the linear absorption coefficient given by the X-rays Computerized Tomography. This is a promising method to measure the crack opening from the X-rays projection normal to the crack surface. The fundamental formulae for the crack opening measurement have been firstly described as well as the necessary regional averaging technique and the data processing for measurement of accuracy to micron meters, and subsequently the crack model experiments using a couple of half-moon aluminum plates has been conducted to examine the accuracy and reliability of the method. As a case example of the Crack Projection Method, the Short Rod testing has been presented and discussed,that is a suggested testing method of the International Society for Rock Mechanics for determining the fracture toughness of rock. Crack growth characteristics with pull-loading has been described by showing the 2-dimensional images of the X-rays Computerized Tomography. The permanent opening displacement of the extended crack has been successfully examined by the subtraction of the crack opening profiles measured before and after the Short Rod testing, and the elastic opening of the extended crack has been also examined by analyzing the change of the crack opening profile by reloading. Moreover, the dimension of the fracture process zone has been estimated as well as the permanent strain in this zone.

Highly pure aluminum was anodized at a constant current density of 25 A m -2 at 293 K in 0.5 M boric acid/0, 0.005, or 0.05 M sodium tetraborate solutions, to examine the effect of sodium tetraborate concentration on the formation and breakdown characteristics of barrier oxide films by using inductively coupled plasma atomic emission spectrometry, electroluminescence/photoluminescence measurements, scanning electron microscopy, transmission electron microscopy, and electrochemical impedance spectroscopy. In boric acid/borate solutions, a crystalline alumina formed locally in the middle of the amorphous oxide film. Above the crystalline alumina, a void is formed and may lead to a breakdown of the oxide film at 420 to 540 V. In boric acid solution, an amorphous oxide film grew until 1180 V with the formation and development of imperfections and with enhancement of electroluminescence and gas evolution. At imperfections. the oxide/solution interface was convex and the oxide/metal interface curved in the opposite direction. This deformation is attributed to high-pressure O 2 evolved in the pores of imperfections and to the local formation and dissolution of oxide. The breakdown of the oxide film started when the O 2 evolution and oxide dissolution at imperfections become predominant. The mechanism of formation and breakdown of the anodic film in the boric acid/borate solutions is discussed in terms of pH buffering of the anodizing solution, and the electronic structure of anodic oxide films is correlated with electroluminescence and photoluminescence spectrum results.

The electric lines of force are trajectories comprising the tangents of the lines of forces that act on the electric charge in the electric field. In the complicated system of the multi-dielectric and multi-conductor media, the lines of force are not necessarily continuous on the interface of the dielectric media. In the engineering application, the visualization of the electric fields is quite essential. It has been strongly believed that the electric lines of force can relatively easily be plotted using numerical analysis. However it is practically difficult to draw the electric lines of force proportional to the intensity of electric field using a scalar potential with the 2-D finite element method. The paper proposes the novel scheme of drawing the electric lines of force based on the electric displacement using the scalar potential and illustrates the distribution of electric field of the capacitor with a long distance as an example.

Basically, the pipe jacking system involving the pushing or thrusting of the drivage machine through concrete pipes ahead of jacks. The method utilizes the mud slurry which is formed around the pipes for stability of surrounding soil. However, it is not well understood the behavior of the soil and mud slurry around the pipes. From this point of view, this paper discusses the seepage behavior of the mud slurry on soil around the pipes by means of laboratory tests and 2-D Eulerian Lagragian analysis.The results of this research are summerized as follows;1) It can be applied to the seepage behavior of the mud slurry by using 2-D Eulerian Lagragian analysis.2) Large slurry permeation zone tends to form thick mud screen around the pipe.3) The mud screen between the soil and the pipe is easily formed by high density mud slurry and high slurry pressure.4) Once the mud screen was formed, the thickness of the mud screen increased gradually because it behaves like a filter paper under pressure.5) Thick mud screen prevents the mud slurry from permeating into the soil.

Indonesia produces over 350Mt of clean coal in 2012 and is the second largest coal exporter to Japan, accounting for 30 Mt/y. Almost of the coal produced is from open cut mines. Mining operation of open cut mines gives serious impacts on surrounding environment. Therefore, an appropriate rehabilitation program has to be taken into consideration when the mine plan is designed. The basic concept of rehabilitation in open cut mines is the creation of a stable and self-sustaining land surface in post mine surface involved the creation of conditions suitable for the establishment and permanent development of a dense cover of vegetation. Hence, the soil characteristics in rehabilitation area and adequate selection of species to plant in there have to be considered. This paper describes the current situations in rehabilitation area at one of open cut coal mine in Indonesia and then discusses the application of Paper Mulberry as one of effective species planted in post mine surface based on the laboratory tests.

As the Internet, computer technology, and peripheral devices continue to grow, web services for users are increasing, including such streaming video broadcast services as YouTube and Ustream that allow users to watch the streaming in which they are interested. In the current streaming video broadcast services, users search for streaming videos by title and tag information. However, since many streaming videos have insufficient information, they are often difficult to find. In addition, since only one streaming video can be watched in one browser, simultaneously comparing two or more streaming videos is difficult. In this research, we propose Multi-Stream Viewer as a simultaneous viewing system for streaming videos with tag information added to the time axis to enable users to watch streaming videos. We also implement and evaluate our proposed system.

The popularity of home appliances continues to increase that can interconnect with other appliances through networks. For users who want to identify the network home appliances they want to operate, their operation is complex and difficult since their locations are not represented within the operating system. We propose Embodied Visualization with Augmented Reality for Networked System 3 (EVANS 3) to solve operation problems with obvious and intuitive controls by implementing augmented reality (AR) technology. We implemented our proposed LED Marker instead of the use of graphical images (image markers) as the AR markers to identify the network home appliance's location at any distant and altering light environments. By dynamically operating LED Markers, we can achieve a comfortable and effective appliance authentication environment for suitable operating conditions.

In Japanese open pit limestone quarries, the drill and blast method using the bench cut system is employed. Since the success of drilling machine is more sensitive, its application should be made after proper evaluation of geological conditions and rock characteristics in order to predict the machine performance and bit consumption and so on. Geological conditions have a significant effect on the performance of drilling machine. Unconfined compressive strength or uncofined tensile strength of intact rock which is used as an index for criterion or prediction is not good because the fragmentation mechanism is not considered well. It is more important to consider the consumed energy value in fragmentation such as the rock impact hardness number (RIHN) than the strength failure value such as the unconfined compresive strength or the unconfined tensile strength for criterion or prediction of machine performance.From these points of view, this paper discusses the predicting method of the drilling rate and the selecting method of the drilling machine by using the rock impact hardness number, RIHN.

In the fission yeast Schizosaccharomyces pombe, deletion of trt1(+) causes gradual telomere shortening, while deletion of pot1(+) causes rapid telomere loss. The double mutant between pot1 and RecQ helicase rqh1 is synthetically lethal. We found that the trt1 rqh1 double mutant was not synthetically lethal. The chromosome end fragments in both the trt1Δ rqh1Δ and the trt1Δ rqh1-hd (helicase dead) double mutants did not enter a pulsed-field electrophoresis gel. Both the trt1Δ rqh1Δ and the trt1Δ rqh1-hd double mutants were sensitive to the anti-microtubule drug thiabendazole. Moreover, the trt1Δ rqh1-hd double mutant displayed RPA foci on the chromosome bridge at high frequency in M phase cells. These phenotypes are very similar to that of the pot1Δ rqh1-hd double mutant, in which recombination intermediates accumulate at the chromosme ends in the M phase. These results suggest that the entangled chromosome ends, most likely recombination intermediates, are present in the M phase in the trt1Δ rqh1-hd double mutant.

In recent years roadheader has been a predominant method of tunnel drivage in Japanease coal mines. Since the success of roadheader is more sensitive, its application should be made after proper evaluation of geological condition and rock characteristics in order to predict the machine performance and bit consumption and so on. Prediction of the performance of roadheader has in the past been based upon unconfined compressive strength. However, this prediction is not good because the fragmentation mechanism is not considered well. It is more important to consider the consumed energy value than the unconfined compressive strength for criterion or prediction of machine performance.From these points of view, this paper discusses the specific energy in terms of surface area obtained by the impact hardness test in order to estimate the performance of heading machines. Predicting equation having good correlations with the performance of roadheader drivage has been developed by using the RIHN (Rock Impact Hardness Number) and the rock mass property, RQD (Rock Quality Designation).

The popularity of network home appliances that can interconnect with other home appliances through networks increases. The operation and function of these appliances are complex since they can share contents and data with other network home appliances. However, it remains difficult for users to identify network home appliances, since their locations are not installed and cannot be displayed easily when operating them. Because these problems, more obvious and intuitive operations are needed for controlling network home appliances. For this solution, we have implemented augmented reality (AR) technology in our past proposed system for easier, intuitive operation to control multiple network home appliances connected by home networks. AR technology can provide virtual graphics and apply additional information to specific areas through camera displays. In current AR technology, an AR marker made from a graphical image (an image marker) is necessary to display the virtual AR graphics to the devices's identified location. Unfortunately, such image markers are not suitable when they are implemented on network home appliances due to poor recognition when lighting environments or distances are changed. In this paper, we explain the LED augmented reality marker (LED marker), implement a new marker, and evaluate it, and consider a collaboration system for controlling multiple network home appliances connected to home networks.