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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.

There are various kinds of wireless network devices, such as cellular phone and wireless sensors, around us in a ubiquitous environment. Unlike a wired network, we cannot grasp the exact status of a wireless network in real space. Moreover, it is difficult to understand the relationships of connectivity intuitively, since network management software is used in a virtual two-dimensional space. We propose and implement EVANS (Embodied Visualization with AR for Network System) as a visualization system for wireless networks. EVANS shows the status of a wireless network on an interface that uses AR technology, which allows us to grasp the status among nodes intuitively. In addition, we can use EVANS to actually manipulate nodes in real space by manipulating the annotations on the AR interface.

Experimental results for the penetration of conical bits into rocks have been obtained and compared to theoretical results derived from an existing bit penetration model which is similar to the one established by Dutta. The tests were made in sandstone, andesite and granite using seven indenters with apex angles in the range 60-150°. Moreover, the effect of mechanical anisotropy on bit penetration behaviour was examined using sandstone. For the smaller apex angles chipping was predominant whereas for the larger apex angles essentially only crushing occured.Crater volume and force-penetration curves were measured, and the theoretical cutting efficiency and the ratio of volume to work were evaluated. Using those values of the mentione parameters, quantitative consistency between theory and experiment is obtained. Accordingly, the penetration model has the capability of predicting quantitatively the rock cutting and drilling behaviour.

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 impact hardness of rock is normally determined by using a ‘Protodyakonov’ type drop hammer. However, this test cannot be applied to a wide range of rocks. Therefore, standardized impact hardness test using the ‘Protodyakonov’ type drop hammer was carried out and the correlati ons of the resulting values of impact hardness with the mechanical properties obtained from usual laboratory tests were investigated.The results show that the impact hardness has, a generally good correlation with the tensile or the compressive strength of rocks. Therefore, the impact hardness can be used as a strength index in the estimation of rock properties. Moreover, the performance of rock drilling or machine roadway drivage can be predicted using the impact hardness of rock.

In this paper, we propose the wireless LAN system using the airship. The wireless LAN system on the airship is tracked by the image processing automatically and provided the Internet connectivity to users on the ground in our proposed system. We describe the requirements of the wireless LAN system for the airship and design the architecture. To estimate the performance of our proposed system, we have performed the experiment with the airship flying in the real space. Experimental results indicate the validity of the wireless LAN system of image-based tracking antenna.

A Knowledge of the mechanical properties of rocks is essential for geotechnical engineering problems. Most tests which are usually used to determine the strength of rock require the specimen to be in the precisely prescribed shape. However, it is often difficult, or practically impossible in some cases, to prepare the specimen as required, with weak rocks or potentially fractured rocks.On the other hand, considering the mechanical cutting of the rocks, it has been investigated to relate the bits with the properties of rocks. However, it is not sufficiently understood that the mechanism of the bit penetration by the reasons of which is dependent on the properties of the rocks, the shape and size of the bits etc. Accordingly, it is possible to obtain the useful correlation between the drillability and the observed chipping or crushing by the rod penetration test.From this point of view, the rod penetration test has been carried out by using a wide range of rocks from weak to hard. Various correlations have been thoroughly examined in accordance with the properties obtained from the rod penetration test and the usual mechanical tests. It is shown that the strength and deformability can be estimated from the results of the rod penetration test, for a wide strength range of rocks.In addition, the mechanism of the fracture development during the rod penetration test have been investigated by means of FEM analysis. It is shown that tensile fractures under the loaded rod and the direction of indentation play an important role in effective fragmentation of rocks.

There have been many wireless sensors equipped IEEE 802.15.4. ZigBee, the most representative upper layer protocol of IEEE 802.15.4 is non-IP-based. However an IPv6 protocol called 6LoWPAN is currently being discussed by the IETF. Until now, IP stacks have generally been too large for sensor devices, which have weak calculating ability. Thus, most of wireless sensor networks are non-IP networks. The Internet, of course, generally are using IP. If we can use IP with wireless sensor networks, we can reap the benefits of the IPpsilas superior technology. Researches in this field aim to develop wireless sensor networks using IPv6 and obtain the efficiency of IP-capable wireless sensor networks. However, problems with the buffer overflow have been reported in some implementations of 6LoWPAN. In this paper, we propose a memory buffer control mechanism for 6LoWPAN, and evaluate an implementation of a 6LoWPAN protocol stack using this mechanism. Results of this implementation have shown that the buffer control mechanism worked efficiently.

The seven members of Shaker-related K(+) channel family, which are known to regulate membrane excitability and transmitter release, have been identified in the CNS. It is known that the substantia nigra pars reticulata (SNr) receives GABAergic inputs mainly from the striatum and sends GABAergic outputs to the thalamus. An immunohistochemical study shows that the Kv1 family, particularly Kv1.4, is expressed in the SNr, while it is reported that Kv1.2 mRNA is detected in the striatal neurons. Therefore, which Kv channels may be involved in the release of GABA in the SNr remains still controversial. To address this issue, we tested the effects of various K(+) channel blockers on the synaptic transmission using mechanically dissociated SNr neurons known as "synaptic bouton preparation", that retained functional presynaptic nerve terminals which enable us to examine miniature inhibitory postsynaptic currents (mIPSCs) by conventional whole-cell patch clamp recordings. Based on the sensitivities of mIPSCs to the Kv channel blockers, we concluded that Kv channels, in particular Kv1.2 subunit play the most significant role in the release of GABA at the presynaptic terminals projecting to the SNr neurons.

The experimental study is conducted to estimate fracture process of the cylindrical rock specimen. In this experiment, an explosive is used as the explosion source, and a pipe filled with water is arranged between the explosive and the cylindrical rock specimen. The main purpose of this fracture test is to collect the experimental data on the behaviors of the dynamic fracture of the rock. In addition, one of the aims of this test is to estimate the dynamic tensile strength of the rock in wide range of strain rate utilizing Hopkinson's effect. Therefore, during the fracture process of the rock, the free surface velocity and the fracture part near the free surface were observed by a laser vibration meter and high speed camera. The precise detonator was used to control the initiation time of the explosive by using an accuratley controlled blasting machine. The results of the fracture test for Kimachi sandstone and the validity of this test are discussed. In order to understand the relationship above fracture condition and the incident underwater shock wave into the rock specimen, the numerical simulation is carried out. The 2D hydrodynamic code based on ALE finite difference scheme is employed. In the case of the fracture test with 50 mm water pipe, the incident underwater shock wave into the cylindrical rock specimen has irregular pressure distribution near the shock front.

Mobile hosts can acquire location-dependent information at any place and be connected to a network from anywhere with wireless communication devices such as cellular phones, wireless LAN, etc. In such an environment we aim to construct a system software on which mobile hosts can share the location-dependent information with other hosts. It is, however, difficult for users who request location-dependent information to identify mobile hosts providing the information, since the system presents no mechanism to specify hosts by geographic location. In this paper we propose a location management system that manages locations of mobile hosts and enables users to specify location-dependent informations by their geographic locations. Since the location management system is employed for mobile computing, the system has the mechanism to reduce the overhead of location management on wireless communication. Moreover, we implement a part of this system and show that this system is suitable for mobile environment through the experiment.

The processes of the laser initiation of pentaerythritol tetranitrate (PETN: density 1.0g/cc) are calculated using one‐dimensional hydrodynamic code to study the effects of the initiation methods on the initiation process. The simplified assumptions for the initial condition are used to model the three types of the initiation method, utilizing direct absorption of laser energy, impact of the laser driven‐flyer plate and ablation of the metal film. The governing equations are Lagrangian conservation equations and are solved by a finite difference method. The reaction rate law is used the ignition and growth model.

The donor and the acceptor charges are arranged into the water with the interval. The donor charge has a cylindrical geometry with 30 mm diameter and 50 mm long. The acceptor has a disk form with 100 mm diameter and 10 or 5 mm thickness. Composition B is used for both of the donor and acceptor charges. The propagation processes of underwater shock waves from the top end of acceptor charge along the axis of charges are taken by the image converter camera under the intervals of 10, 15, 20 and 25 mm. In the case of 10 mm thick acceptor charge, the velocities of the underwater shock wave are the almost the same up to the interval of 20 mm. However, in the case of 25 mm the underwater shock wave has remarkable low velocity compared to the other cases. In the case of 20 mm interval, the velocity of the underwater shock wave in the case of the 5 mm thick acceptor is slower than that of 10 mm. Furthermore, the numerical simulations are conducted. The reaction rate law of the high explosive is a phenomenological model that is proposed by Lee and Tarver. The results of the optical measurement and numerical simulation demonstrate a good agreement.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

This paper presents the study on the application of explosive welding technique to the field of the urgent repair of the gas and water pipe networks. The essential parameters related to the explosive welding are scrutinized from the point of view of the minimizing the damage to the steel pipe after welded explosively with a flyer plate. The emulsion explosive is contained in a rectangular hard-paper box whose bottom is the flyer plate with 100 mm length, 25 mm width and 1.5 mm thickness. The flyer motions of the flyer plates accelerated by emulsion explosive are observed by high-speed photography from the side and front view of the flyer plate. The damage to the pipe by the flyer plate is discussed with the results of the observation of flyer motion and explosive welding test under various experimental conditions. Moreover, one way to control the motion of the flyer plate is proposed. We put a PMMA buffer block into the explosive. The flying process of flyer plate is calculated by the finite different scheme based on the ALE method. The effectiveness of this method is demonstrated by the experimental and numerical studies.© (2001) COPYRIGHT SPIE--The International Society for Optical Engineering. Downloading of the abstract is permitted for personal use only.

A Knowledge of the mechanical properties of weak rocks such as shale, sandy shale and coal is essential for ground control in undeground coal mining. Most tests which are usually used to determine the strength of rock require the specimen to be in the precisely prescribed shape. However, with weak rocks it is often difficult, or practically impossible in some cases, to prepare the specimen as required by these tests.From this point of view, rod penetration test has been carried out, because in this method an unprepared specimen can be used.The results of this study are summarized as follows:1. The size of specimen should be at least 10 times the rod diameter.2. Size effect of rod on penetration strength Srp is caused by difference in fracture mechanism of rock around the top the penetrated rod.3. Penetration modulus Erp is not dependent on the rod size.4. Uniaxial strength Sc and tangent Young's modulus at 50% of compressive strength E50 can be estimated with penetration strength Srp and penetration modulus Erp as follows; Sc=0.11·Srp, E50=2.3·Erp.5. It is possible to estimate the strength reduction with water quantitatively by this test.

The interaction effects in multi-seam mining depends on many factors such as local geological and geotechnical conditions, mining depth, seam sequencing, and mining method employed, etc. The paper discusses preliminary study on the interaction effects in underground mining of double extra-thick coal seams in Mae Moh coalfield in Thailand. The Mae Moh mine is currently operated as open pit mine by EGAT (Electricity Generating Authority of Thailand) and it is the largest open -pit lignite mine in Thailand. In the near future, the final pit limit of the mine will be reached and underground mining will be commence d from the final highwall in the depth of 400-600 m from the surface. However, due to the challenges such as poor geological and geotechnical conditions, extra-thickness (20-30 m) of the coal seams and huge final pit slope, success probability for underground mining are being evaluated at the present. This paper discusses the ground response and possible interaction effects in the double extra-thick seams mining by means of numerical analyses using three dimensional finite difference code FLAC3D.

Almost all the coal is produced from open cut mines in Indonesia. As a consequence of open cut mine application, a great deal of coal is left out in the highwalls of the mined-out pits. Highwall mining systems can be used to recover this coal. The use of highwall mining systems has increasingly come into play in the US and Australia. However, it is not common in Indonesia. Moreover, Indonesia coal measure is categorized as weak geological condition. Some problems are likely to arise during the application of the highwall mining system for example instability of openings and highwalls due to the roof and pillar failures. Therefore, study of highwall mining system application in Indonesia is needed in order to increase the recovery rate of coal mining in Indonesia. This paper described the characteristics of the highwall mining system and discussed the appropriate highwall mining system application in weak geological condition, Indonesia. From the results of a series of laboratory tests and numerical analyses, it can be concluded that the stability of pillars and mine openings in auger mining systems is much higher than that in CHM and an auger mining system is suitable for such as very weak/poor strata conditions. Moreover, the application of backfilling system is very effective for improvement of the stability of pillar and openings.

In order to discuss on the assumptions of simple mixture rule for reacting explosive, shock to detonation transition processes were calculated by finite difference method for high explosive. The reacting explosive was regarded as the simple mixture phase of the reactants and products components. Four kinds of assumptions, such as thermal equilibrium, isentropic reactants, etc. were adopted as one of the assumptions to solve two components variables and to determine the pressure. The numerical results that were obtained under the each assumption had a good agreement with each other. In order to answer the reason why the difference of the assumption is insensitive to the numerical results of shock initiation, the relations of reactants and products components were considered in the specific internal energy and specific volume plane with constant pressure lines for both components.