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By using the piezocone penetration test (PCPT or CPTu), one can develop not only a better understanding of the soil stratification, but also an understanding of soil behavior parameters related to soil compressibility, as well as soil strength. This paper describes a case study that utilizes incomplete piezocone dissipation test to estimate status of consolidation of a soil deposit. Incomplete pore pressure dissipation record of PCPT is extrapolated on an inverse time scale (1/ t method) to estimate the “in situ” pore pressure and “residual excess” pore pressure. No case study has been reported in open literature where this methodology has been utilized to estimate the status of consolidation of the soil deposit. In this paper, the 1/ t method was verified using dissipation data from rigorous calibration chamber tests and field test data.

This study was performed to evaluate the operational parameters on aeration on/off time in an intermittent aeration membrane bioreactor for wastewater treatment. The membrane bioreactor has 5.5 L of effective working volume including a microfiber membrane. The influent wastewater contained 133mg/L of BOD, 195 mg/L COD, 98 mg/L SS, 30 mg/L total nitrogen, and 3.8 mg/L total phosphorous. Operational conditions related to aeration on/off time were 8.8 h HRT, 10 LMH flux, 10 L/min air flow, and 6300 mg/L MLSS. For 2 h/cycle, aeration on/off time was operated for 12 cycles in three variations: 60/60 min, 50/70 min (I), and 40/80 min. Suction on/off time was 10/2 min, 8/2 min, and 8/2 min, respectively, but also 50/70 min (II) when aeration on/off time was operated at 8300 mg/L MLSS. The BOD removal efficiency rate of this process was higher than 97% regardless of the aeration on/off time distribution. To get higher than 82% total nitrogen removal efficiency rate, aeration off time in the reactor needs to be more than 70 min. The specific denitrification rate was 2.68 mgNO 3 -N/gMv/h at 40/80 min on/off aeration times, which was 2.6 times more than at 60/60 min, and 1.4 times more than at 50/70 min (I) for 6300 mg/L MLSS. The specific nitrification rate was 1.96 mgNH 4 -N/gMv/h at on/off aeration times of 50/70 min, 1.4 times less than at 40/80 min, but was ineffective for nitrification. Microbial activity was affected only a little by variation in aeration on/off time, though oxygen demand was reduced by aeration off time and allowed microbial concentration to increased. EPS (extracellular polymeric substance) per unit of microorganisms increased with aeration off time.

The KSTAR (Korea Superconducting Tokamak Advanced Research) superconducting magnet system adopts a superconducting CICC(Cable-In-Conduit Conductor) type conductor. It consists of 16 TF (Toroidal Field) coils and 14 PF (Poroidal Field) coils and it also uses two different types of CICCs-Nb3Sn cable with Incoloy 908 conduit and NbTi cable with 316LN stainless-steel conduit. A special CICC jacketing system is developed for the KSTAR CICC fabrication: the tube-mill process, which consists of forming, welding, sizing and squaring procedure. The cabling process for TF and PF superconducting cable and the fabrication process of each CICCs (TF CICC and PF CICC) is described. The welding of conduit materials are also discussed. The fabrication results such as the geometrical specification, micro structure and the void fraction will be discussed

The KSTAR Central Solenoid Model Coils (CSMC), which are in the form of split coils with same dimension, have been tested. The CSMC were successfully charged up to 20 kA and down to zero with different ramp rates. Various pulse waveforms were applied to the CSMC to analyse the AC-loss characteristics of the coils. The measurement method was a gas-flow calorimetry. In this work, two types of waveforms, the DC-biased sinusoidal wave (Idc=2, 4 kA; DeltaIac=1 kA; f=0.08~0.67 Hz) and a single triangular pulse (Imax=6~10 kA; dI/dt=0.5~2 kA/s), are selected and analysed. From the measured data at the one outlet where helium channel 3 and 4 are merged, the AC loss parameters, related with the hysteresis loss and the coupling loss, are calculated. The B-field strength differs depending on the position within the cooling channels. The spatial field variation and the ramp rate were 0.048~1.9 T and 8.1~ 71 mT/s for the DC-biased sinusoidal waves, while 0.29~ 4.3 T and 0.024~ 0.86 T/s for the triangular pulses. The measured AC losses are compared with estimated values and the behavior agrees well. The coupling time constant (ntau) varies with the field strength. In case of the triangular pulses, ntau increases by increasing the field amplitude and the maximum value of ntau is 41 ms with Imax=10 kA

The KSTAR (Korea Superconducting Tokamak Advanced Research) superconducting magnet system which consists of 16 TF coils and 14 PF coils adopts a superconducting CICC (Cable-In-Conduit Conductor) type conductor. The KSTAR magnet system uses two different types of CICCs-Nb/sub 3/Sn cable with Incoloy 908 conduit and NbTi cable with 316LN stainless-steel conduit. A continuous CICC jacketing system is developed for the KSTAR CICC fabrication and the jacketing system uses the tube-mill process. It consists of forming, welding, sizing and squaring procedures. The welding condition of CICCs and the fabrication process is described. The repair of the CICC is also discussed.

The KSTAR superconducting magnet system consists of 16 TF (Toroidal Field) and 14 PF (Poloidal Field) coils. Both of the TF and PF coil systems use internally-cooled Cable-In-Conduit Conductors (CICC). The PF coil system, which consists of 8 coils in the CS (Central Solenoid) coil system and 6 outer PF coils, provides 17 V-s and sustains the plasma current of 2 MA for 20 seconds inductively. PF 1-5 coils use Nb/sub 3/Sn CICC in an Incoloy 908 conduit and PF 6-7 coils use NbTi CICC in a modified stainless steel 316LN(316LN+). The fabrication of PF7L/U & PF6L/U coils is completed at present. The engineering issues and fabrication process, which are related with the KSTAR PF 6-7 coil development, are presented and discussed in this paper. TF and PF coils are in the fabrication stage for KSTAR completion in the year 2006.

This study was performed to increase the treatment efficiency and to reduce operation and maintenance costs of the existing nightsoil treatment plant. The existing nightsoil plant was not established by the nitrogen removal process, and was operated ineffectively with deterioration of treatment efficiency rate, and according to the demand of many operators, the expenses of operation and maintenance have become excessive. Modified plant has been changed through two steps. The first step, liquid decayed tank using closed oxidation ditch is operated to increase retention time only for nitrification. The second step, modified liquid decayed tank including anoxic tank is operated, it has an excellent nitrogen removal rate. In first step, when HRT was increased from 10 days to 13 days in liquid decayed tank including aeration tank using closed oxidation ditch, TN concentration of effluent appeared below 51 mg/l less than discharge limit, 60 mg/L. In second step, when anoxic tank and oxic tank were installed, HRT has been increased to 13 days and 26 days, respectively. Then average TN concentration of effluent was detected less than 13 mg/L for over one year. The simple process modified the existing two processes resulted in the reduction of costs for operation and maintenance in the personnel, chemical, and filter change sphere.

High rate algal ponds (HRAP) with a filamentous algae matrix (FAM) as the predominant species, were operated to evaluate the characteristics of FAM and the basic design parameters for treating polluted rural stream water. The porous and gelatinous FAM was formed like a sponge, which functions to prevent excessive loss of the algae in the effluent and can easily be retrieved from the ponds. The organic fraction of harvested FAM was about 88%, which is suitable for use as fertilizer. The HRAP system using FAM was found to be an effective nutrient removal process not requiring any artificial carbon sources for nitrification. At HRT 4 days, the T-N and T-P removal efficiencies were 85.9% and 65.8%, respectively. When the pH and water temperature were maintained above 9 and 15°C, HRT required for achieving a 70% T-N removal efficiency could be reduced by about 3 days. The oxygen production rate by FAM was calculated as 1.45 mgO2/L/m2. The design surface area of HRAP needed per rural inhabitant was about 2.72 m2.

In this paper, we present the simple approach in study the impact of channel doping on the operation of the junctionless transistor transistor in 25 nm gate lengths through 2D-TCAD Sentaurus simulation tools. We increase the channel doping up to the level of doping source and drain, thus creating the junctionless phenomena between source and drain. The transistor parameters such as threshold voltage, transconductance, subthreshold slope, drain-induced barrier lowering are extracted. The impacts of low and high drain voltages are also considered. The higher the doping concentration the larger drain current can be produced, however the drawback is larger subthreshold slope is also obtained due to wider channel preventing fully-depletion.

The determination of different rates of endogenous nitrate respiration due to biomass stratification throughout the depth of a sludge blanket is essential to assess the factors affecting the sludge rising in secondary clarifiers. In this study, an extension of the solids flux theory in conjunction with nitrate mass balance was used to model the fate of nitrate in a sludge settling column. The model-predicted nitrate concentrations agree well with those experimentally determined. A new term, sludge stability index, was introduced to reflect the sludge rising time and the corresponding critical nitrate concentration necessary for causing sludge rising. The model predicted well the observed sludge rising times occurring under batch settling column experiments with initial biomass and nitrate concentration ranging from 2000 to 5000 mg l−1 and 10 to 30 mg-N l−1, respectively. Furthermore, simulation results indicated that both the sludge rising time and CNC are significantly affected by kENR.

A fresh perspective on the inspection planning (IP) process is considered, which views IP as a concurrent engineering (CE) activity which is carried out during the detailed design (DD) stage. Problems related to the computerised enabling of CE are highlighted. Design-by-features (DBF) methodology holds promise for bringing CE concepts out of academia into industry; although conceptually and implementationally the feature concept brings with it a host of other problems. A significant number of parameters required in an IP are decided at DD. Relevant CE-assign-able parameters are discussed under the classifications: functional, auxiliary and geometric, each of which are implementable as features in a DBF system. Some of the major hurdles to implementing ‘ interactive’ CE are also discussed. A ‘DFx cum process-planning-for-x’ orientation at the DD stage of the product life-cycle is put forward as one approach to CE.

A number of Debye-type dielectric relaxation peaks have been observed for acceptor-doped KTaO3 and CaTiO3, both of which have the perovskite structure. In the case of KTaO3, the dopants are divalent and trivalent cations of the iron group, while CaTuO3 is doped with Al3+. These peaks occur at relatively low temperatures and have activation energies in the range 0.1–0.4 eV, much lower than the activation energy for the conductivity. They are attributed to M-Vo pairs, where M represents the dopant ion and Vo the oxygen ion vacancy. The possibility that the peaks are due to partial reorientation of the pairs in “off-center” configurations is ruled out by electron paramagnetic resonance work on Mn-doped KTaO3 by Geifman and coworkers (I.P. Bykov, I.N. Geifman, M.D. Glinchuk and B.K. Krulikovskii, Sov. Phys. Solid State, 22 (1980) 1248). They must therefore be due to full reorientation, and possible reasons for the low activation energy are discussed. A study of the peak heights shows that a large correction for internal field effects is necessary for KTaO3, but this correction is not nearly so large as that given by the Lorentz factor.

Turning the free edge of an unstiffened flange inwards or outwards to form a ‘lip’, can substantially improve the local buckling resistance of a member. The lip is the most common type of edge stiffener used in cold-rolled, thin-walled sections. In this paper the behaviour of plate elements of thin-walled sections stiffened by compound lips (i.e. lips which are folded twice to form ‘lips on the lips’) is examined both theoretically and experimentally. An outline of a series of tests on compound edge-stiffened thin-walled sections of various geometries is given and some load-end compression displacement paths are compared with the theoretical predictions. Reasonably good agreement is obtained between the experimental and theoretical results. Comparisons of the theoretical predictions with experimental results of other researchers are also presented in this paper.

The ac conductivity behavior has been studied for crystalline oxygen-ion conductors: CeO 2 :Gd 3+ and CaTiO 3 :Al 3+ as well several silicate and borate glasses over a wide range of temperature. In all cases, Jonscher's universal power law behavior: σ ( ω )= σ (0)+ Aω s is observed, where σ(0) is the dc conductivity and s the power law exponent. Furthermore, there are three regions of behavior. At the higher temperatures, s is a constant (usually≈0.6) independent of T . In this range σ can be written in the form suggested by Almond and West: σ ( ω )= σ (0)[1+( ωτ ) s ]. We find that τ has the same activation energy as σ(0) and a pre-exponential ≈10 −14 s. However, the quality of the activation energies does not imply that all carriers are unassociated, as Almond and West have claimed. Rather, it suggests that the ac and dc parts of the conductivity are manifestations of a single hopping process involving ion-ion interactions. At lower temperatures, the exponent s increases as T decreases, finally leveling off at s =1.

Partial Discharge (PD) detection has been used in assessment of condition reliability of electrical insulation in high voltage equipment such as power station. Unfortunately, PD signals took during condition monitoring are often corrupted with excessive interference. The challenge to effectively and accurately determine and extract the pure PD signal from the large amount of noise still remains. The focus of this paper is to explore artificial intelligence as a new denoising method for pure PD signal detection, especially for extracting low amplitude PD signals that are initially grouped with the noise signals. A Fuzzy Self-Organizing Maps (FSOM) method has been developed. It combines the concepts of Kohonen Self-Organizing Maps (SOM) with fuzzy sets theory. A Fuzzy Classifier based on the FSOM is built to eliminate noise and extract pure PD signals. Two sets of laboratory-simulated signal data, surface and cavity, were used for the method verification. It is shown that the developed Fuzzy Classifier is superior to conventional threshold-filtering method in extracting the PD signals in the lower amplitude range.

This paper presents a method suitable for on-line estimation of RFID data traffic load in a RFID network, specifically the average arrival rate of each reader. The novel approach comprises of measuring the dynamics of tag data flow into middleware from associated readers including the average dwelling time of a tag in a reader and average tags arriving from the respective readers to the Middleware. Simulation results showed that the estimation error does not exceed 15%. Knowing the average arrival rate is important because it can be used for dynamic management of readers by a middleware to improve system response time.

A new self-driven active clamp forward converter, in which the extra driving circuit for the active clamp switch is not required, is proposed. In the proposed converter, the auxiliary winding is used instead of the extra driving circuit to drive the active clamp switch so that the converter has a simple structure comparing to the conventional one. The operation principles of the proposed converter, in which synchronous rectification is employed, are presented. Experimental results for the prototype converter of 100 W(5 V/20 A) are also presented to verify its validity.

Publisher Summary Benzene, toluene, and xylenes (BTX) are a valuable petrochemical feedstock that can be produced from aromatic rich stream by upgrading naphtha reformate or pyrolysis gasoline in the refinery. However, with the advent of the modern continuous catalyst regeneration (CCR) reformer, the operation of conventional fixed bed reformer has declined drastically. There are also ample supply of the low value naphtha reformate. It is therefore desirable to produce BTX enriched aromatic stream using the surplus reformate in the idled unit. Aromatics produced can be recovered by solvent extraction. But the extraction unit in the loop has limited processing capacity to handle the extra amount of BTX produced. A novel noble metal that promoted shape selective zeolite catalyst is developed to utilize the idled fixed bed reformer to convert surplus reformate into valuable BTX streams and liquefied petroleum gas (LPG) without adding extra burden to the solvent extraction columns.

The ac conductivity was studied for different compositions of CeO2 ceramics, undoped and doped with Y3+ ions in the composition range 1 to 12 atomic %Y over the temperature range from 50 K to 500 K. It was observed that in temperature range 300-400 K, the ac conductivity (as well as the real part of the dielectric constant, ε',) follows the universal power-law frequency dependence with exponent s ≈ 0.63. No systematic variation of s, either with temperature or with dopant concentration, was observed, although for nominally “pure” CeO2 no power-law regime was observed. The features of the ac behavior were explained on the basis of a percolation approach.

Many disordered materials both crystalline and glasses show universal dynamic response [1], which is characterized by appropriate power-laws. The ac-conductivity as a function of frequency, is given by: σ(ω)=σ(0)+ Aωs where σ(0) is the dc-conductivity and the exponent s (≤1) generally decreases with increasing temperature. In previous work on ionically conducting crystals and glasses, we have observed two ranges in which s = constant, independent of temperature: at high temperatures, s=so (a value between 0.5 and 0.6) and, at low temperatures, s = 1. Further for the s = so region, the parameter A is activated with activation energy related to that of σ(0), while for the s = 1 region, A varies only slowly with temperature. For the cases of borate and silicate glasses as well as for crystalline CaTiO3 doped with 30% A13+, careful analysis was carried out over the region in which the effective s falls from 1.0 to so. The results show that this region can be described by the relation: σ(ω)= σ(0) + Aωs0 + A'ωl.0 with parameters A and A’ consistent with those obtained from the high and low- temperature regions, respectively. Thus, we conclude that two separate types of universal behavior are superimposed throughout the entire temperature region; each is described by a constant value of s, and is due to an independent mechanism of non-Debye relaxational behavior.

The effects of lithium carbonate on the ultrastructure of the rat kidney were studied. Fifteen male rats of the Sprague-Dawley strain were given aqueous lithium carbonate by mouth, 74mg/kg/day. These rats were killed on days 5, 10 and 15. Six control rats were given NaCl solution equivalent in volume and tonicity to the lithium dosage. Blood analyses were performed on both experimental and control animals. Test animals with a serum level of 0.5mEq/L showed marked hypertrophy of endothelial and epithelial cells in the glomeruli. The capillary lumens and urinary spaces were almost completely occluded by these enlarged cells. Among the prominent features of these cells were the hypertrophy of the Golgi apparatus and an increase in the rough endoplasmic reticulum. Similar proliferation of the Golgi apparatus was also observed in the epithelial cells of the proximal, distal and collecting tubules.

The true potential of a CIM system cannot as yet be fully realised. A further requirement is for a device which can extract manufacturing information from the outset. The main aim of the research described in this paper is to develop a knowledge-base system for extracting such information and to promote a coming together of design and manufacture. The major goal must be to enable industry to manufacture without manual intervention. A prototype knowledge-base system called HOLDEX described in this paper is an implementation that relies on combining the advantages of existing technology such as AI, CAD representation schemes, advanced manufacturing systems, man-machine interface and most importantly the encapsulated knowledge of a manufacturing engineer. The aim of the prototype system is to encourage a workpiece designer towards manufacturing standards and to assist him in the use of a general purpose CAD package. One benefit to be obtained from providing such assistance is to facilitate the ease of extracting manufacturing information. The scope of the extracted information includes the detailed specification of a set of cutting tools, the recognition of a list of required activities prior to a machining operation, the recommendation of the appropriate machine tool and the automated design of fixtures.

Using specimens from various organs originally processed for routine histopathological study (wax embedding), a total of 2044 autopsy cases were reviewed to identify those with primary amyloidosis of the heart. A total of 7 such cases, involving the heart only, was identified with the aid of appropriate stains and polarized light. The heart tissue was subsequently re-processed for study by electron microscopy. In all 7 cases, large deposits of amyloid fibrils were found around the blood capillaries and smaller amounts between individual myocardial fibres. The possible origin of the amyloid fibrils is briefly discussed within the limitations imposed by the source of the material; it is suggested that they may be formed either by the muscle cells or from material reaching the tissue via the capillaries or alternatively, as the result of an interaction between the cells and circulating immunoglobulins.

The advent of CAD/CAM system, robotics simulator and off-line programming tools has provided a significance contribution to advanced manufacturing technology. A natural progression would be to integrate these computer aided tools with a robotics workcell within a flexible manufacturing system, FMS. Such an integrated approach is currently developed within GINTIC for the assembly of modular fixtures in its intelligent flexible manufacturing system, IFMS for the machining of complex shape components. This paper describes the configuration and development of this system. The functions associated with each modules within the integrated robotics off-line programming system will be also elaborated.

Subsequent to the deposition and annealing of either V or Mg on Si, the reaction to form VSi 2 or Mg 2 Si was analyzed using the following: X-ray diffraction to detect compound formation, AES to locate the two suicide interfaces, and SIMS to follow the diffusive separation of the natural abundance of Mg isotopes in the compound. The SIMS data show that the more massive Mg isotopes are found further from the Mg/Mg 2 Si interface. Such an observation is consistent with Mg being the mobile isotope in the reaction and with grain boundary diffusion being the dominant kinetic mechanism of film growth. Silicon isotope separation was not found for either reaction; however, silicon is not mobile in Mg 2 Si formation so separation is not expected. The thickening kinetics for both reactions is parabolic.

A method is proposed for the indirect determination of trace amounts of cyanide. After release and distillation of the cyanide, which is collected in 1·0 M sodium hydroxide, the cyanide is reacted with a known and excess amount of copper(II) ions. The excess of the Cu(II) ions is determined by polarography, and from the amount of Cu(II) which has reacted, the amount of cyanide originally present is calculated.

A study is made of irradiation effects on α-quartz crystals using the techniques of electrical conductivity and dielectric loss measurements. The initial radiation-induced conductivity (RIC) induced by X-ray irradiation over the temperature range from 94 to 250 K is found to have a nearly constant activation energy of 0.29 ± 0.02 eV. Since a large RIC still results from irradiation at temperatures too low for alkalis to be liberated, it is proposed that the RIC is due to holes (as small polarons) rather than to alkalis. The dielectric loss measurements in Na-swept quartz are used to follow the changes in the relaxation peaks due to the Al-Na defect as a function of radiation dose and annealing. At the same time a low-temperature “irradiation peak” is studied. Restoration of the main Al-Na peak during annealing occurs in two stages: one near 500 K and the other above 600 K. From the observed behavior of the irradiation peak in various crystals, it is concluded that this peak is probably due to alkali centers. Finally, a defect model interpreting the two annealing stages is presented.

Peroxisomes in normal human hepatocytes are catalase-containing rounded or oval organelles with an average diameter of 0.63 μm (l). They are usually surrounded by single tripartite membranes. Their presence can be easily demonstrated by the use of 3,3' diaminobenzidine (DAB) stain in the presence of H202 (2). This paper represents an ultrastructural study of peroxisomes in tne liver biopsy of an alcoholic patient with preoperative diagnosis of fatty infiltration.Biopsy tissues were fixed in 5% glutaraldehyde in 0.1 M phosphate buffer (pH 7.4), postfixed in 1% OsO4 and embedded in epoxy resin. Thin sections were stained with lead citrate and uranyl acetate and examined with a Zeiss EM 9 S-2.Light microscopic study of the liver biopsy reveals an intact hepatic architecture. The hepatocytes appear slightly edematous and possess many eosinophilic granules.Electron microscopy (Fig l) reveals that there is a marked increase in the number of randomly distributed peroxisomes in alcoholic human hepatocytes.