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AFSC processed report ; 2023-01

The temporal modulation of an electron bunch train accelerated from a foil target irradiated by an intense laser pulse is studied by measuring the coherent transition radiation (CTR) from the rear surface of a target. We experimentally obtained CTR spectra from a 1 µm thick foil target irradiated at a maximum intensity of 6.5 × 1019 W/cm2. Spectral redshifts of the emitted radiation corresponding to increases in laser intensity were observed. These measurements were compared with the theoretical calculation of CTR spectra considering ultrafast surface dynamics, such as plasma surface oscillation and relativistically induced transparency. Plasma surface oscillations induce a spectral redshift, while relativistic transparency causes a spectral blueshift. Both effects are required to find reasonable agreement with the experiment over the entire range of laser intensities.

Background Acute heart failure (AHF) is a leading cause of admissions among adults. The COVID-19 pandemic has placed a high burden on healthcare systems globally. Many countries announced lockdowns which restricted residents' movement. There is a reported reduction in AHF admissions during the pandemic in several countries, potentially leading to adverse outcomes such as increased morbidity and mortality. To date, little is known on whether similar trends are observed in Southeast Asian (SEA) countries. Purpose We aim to evaluate whether AHF admissions have been affected by the pandemic and the lockdown restrictions in a multi-ethnic, urban SEA country. We hypothesized that the pandemic and lockdown restrictions (called a “circuit breaker (CB)”) will influence heart failure (HF) admission rates. Methods We conducted a retrospective analysis of patients who were admitted with a principal diagnosis of HF to a tertiary hospital in a SEA country. The study period was from the first confirmed case of COVID-19 (January 23, 2020) to July 31, 2020 (n=378). This was further divided into 3 sub-periods for inter-year and intra-year subgroup analysis. Pre-CB: January 23, 2020 to April 6, 2020, CB: April 7, 2020 to June 1, 2020, and Post-CB reopening (Phase 1 & 2): June 2, 2020 to July 31, 2020. The control period was the same timeframe in the preceding year (January 23, 2019 to July 31, 2019) (n=398) and was similarly divided into 3 subgroups. The primary outcome was the overall HF admission rate. Where appropriate, Poisson regression or Negative Binomial regression was utilised to compare the incidence rate ratios of the HF admissions between the periods. Mann-Whitney test or student's t-test was used to compare the length of stay (LOS) and Charlson Comorbidity Index (CCI) scores. Results Details on the study cohort can be found in Table 1. The study period's overall mean admission rate was 2.08 per day, which was not significantly different from the control (2.00 per day). Subgroup analysis showed that the CB admission rates were significantly lower compared to (i) the control (1.39 per day vs. 2.02 per day) and (ii) pre-CB period in the same year (1.39 per day vs. 2.44 per day) (Fig. 1). Phase 1 & 2 admission rates were significantly higher compared to the control (2.28 per day vs. 1.68 per day), and CB admission rates (2.28 per day vs. 1.39 per day). There were no inter-year or intra-year differences for LOS. There was a significant inter-year difference in CCI scores during the CB period (CB: 2.88 vs. control: 1.97). Conclusions Our study showed significant decreases in AHF admissions during the CB period, and a significant increase in AHF admissions from CB to Post-CB reopening. These suggest that the lockdown restrictions had an influence on patients' health seeking behaviour. We also recognise the need to raise public awareness to encourage HF patients to seek timely treatment, prevent complications and adverse events. Funding Acknowledgement Type of funding sources: None. Table 1. Study cohorts demographicsFigure 1. Weekly HF admissions to hospital in 2020

This work presents fabrication of thermal-piezoresistive nanoelectromechanical silicon disk resonators and their characterization as highly sensitive mass sensors. Forest of multiwall carbon nanotubes (MWCNTs) has been grown on the top surface of the fabricated devices, increasing the resonator effective surface area, which, in turn, increases the adsorption capacity and, therefore, the frequency shift of the sensor in molecular or particulate detection applications. To investigate the effect of the enhanced surface area on frequency shift, devices with and without MWCNTs were exposed to an aqueous solution of manganese sulfate for different deposition times and the resonance frequency shift was recorded accordingly. The measured frequency shift for the devices covered with MWCNTs was $14\times $ higher than similar bare silicon devices. Furthermore, mass loading experiments were performed using gold nanoparticles as the loading mass. A novel way to attach gold nanoparticles on the carbon nanotubes (CNTs) wall was developed here. Oxygen plasma treatment introduced dangling bonds on the MWCNTs walls to facilitate the bonding between them and trimethoxysilane aldehyde molecules, forming the self-assembled monolayer (SAM). After functionalization of the device with SAM and antiinfluenza H1N1 viruses (AB), the device was exposed to a solution of Antimouse IgG (whole molecule)–gold antibody produced in goat products. The results showed more than three times response enhancement for the resonators with MWCNTs.

Accurate estimation of soil loss/deposition forced by rainfall events plays a major role in water resources management and it directly affects the quality of agricultural land and water storage capacity in reservoirs. In this paper, the soil loss model, Revised Universal Soil Loss Equation (RUSLE) was used to quantify soil loss in a small basin located in southern part of Korea. The surface characteristics, such as soil texture, elevation, and vegetation type, are needed to run the RUSLE model. Remotely sensed geospatial data has been successfully used to derive suitable model factors for this purpose. It is, however, difficult to select the grid size of elements for the best fit, which is, often, decided in a subjective and intuitive way. A GIS spatial analysis was performed to investigate the scaling effect for estimating soil loss in the RUSLE model using the remotely sensed geospatial data. The results show that the L- and S- factors are sensitive to the grid size and the optimal resolution to quantify soil loss in the RUSLE model for the study site is 125 m. This approach presents a method to select the suitable scale for estimating soil loss using the remotely sensed geospatial data and eventually improve the prediction of soil loss in a basin scale.

Setting Conventional diagnostic methods for tuberculosis (TB) have limited sensitivity and specificity or are time-consuming. Objective 16S rDNA and 16S rRNA of Mycobacterium tuberculosis complex (MTC) were used as targets to develop sensitive and specific polymerase chain reactions (PCRs) to improve the diagnosis of MTC. Design We developed conventional and real-time PCRs targeting 16S rDNA and rRNA of MTC. Results PCRs targeting 16S rRNA had a 10-100 times lower limit of detection for M. tuberculosis than PCRs targeting 16S rDNA. The sensitivities of the 16S rDNA PCR, 16S rRNA reverse transcription PCR (RT-PCR), 16S rDNA real-time PCR and 16S rRNA real-time RT-PCR for sputum specimens were respectively 92%, 94.6%, 96% and 100%. Real-time PCR showed no cross-reactivity, but conventional PCR had cross-reactivity to M. avium, M. gastri and M. nonchromogenicum. Conclusion PCRs targeting the 16S rRNA of MTC were more sensitive than those targeting 16S rDNA; 16S rRNA real-time RT-PCR showed the highest sensitivity and specificity for MTC.

Dehydroascorbate reductase (DHAR, EC 1.8.5.1) helps to maintain redox pools of ascorbate (AsA) by recycling dehydroascorbate (DHA) to AsA. To investigate whether DHAR influences the acquired tolerance of rice plants to abiotic stresses, cDNA encoding DHAR (OsDHAR1) was isolated from rice and used to develop OsDHAR1-overexpressing transgenic rice plants regulated by a maize ubiquitin promoter. The incorporation and expression of the transgene was confirmed by polymerase chain reaction (PCR) and semi-quantitative reverse transcription PCR, real-time PCR, Western blot and enzyme activity. The overexpression of OsDHAR1 greatly increased the DHAR activity and the AsA/DHA ratio, following increase in AsA content and decrease in DHA content. In addition, the enzyme activity of monodehydroascorbate reductase, glutathione reductase and ascorbate peroxidase, which are related to the ascorbate–glutathione systems, was enhanced in the presence and the absence of salt stress in homozygous transgenic rice plants (OsDHAR1-OX1, -OX2) harbouring Ubi::OsDHAR1. In addition, OsDHAR1-expressing transgenic rice plants enhanced the redox state by reducing both hydroperoxide and malondialdehyde levels under salt and methyl viologen (MV) stress conditions, which led to better plant growth, ion leakage and quantum yield (Fv/Fm). Therefore, our results show that the overexpression of OsDHAR1 increases the adaptation of rice plants to salt stress, by maintaining the AsA pool, ion homoeostasis and redox homoeostasis. Finally, the findings of this study indicate that OsDHAR1 plays an important role in attenuating the deleterious effects of various abiotic stresses.

Introduction Graft rejection remains a major cause of morbidity and mortality following renal transplantation. One of the main determinants of success after renal transplantation is histocompatibility between donor and recipient. Most of the research on this topic has addressed human leukocyte antigen (HLA), but the roles played by minor histocompatibility antigens (mHAgs), such as mitochondrially transmitted antigens, are poorly understood. In this study, we evaluated immune responses induced by minor antigens originating from mitochondrial DNA (mtDNA) in a large animal model. Methods To characterize whole swine leukocyte antigen (SLA) allele in 8 cloned pigs, we performed SLA genotyping for SLA-1, SLA-2, SLA-3, SLA-DQB1, and SLA-DRB1 as well as the hypervariable region 1 (HV1) of mtDNA. Renal transplantation was performed using SLA-matched pigs with different mtDNA as well as SLA-mismatched cloned animals. Cytokine profiling was performed by incubating peripheral leukocytes with cellular components from SLA-matched different mtDNA and SLA-mismatched cells to evaluate mtDNA-mediated immune response. Results SLA types were confirmed to be identical, but mtDNA sequences of HV1 varied among cloned pigs. Rejection episodes in the SLA-matched group with different mtDNA were similar to those in the SLA-mismatched group; that is, plasma creatinine and BUN levels were increased and mononuclear cell infiltration was observed in perivascular regions in the matched and SLA-mismatched groups. Furthermore, in vitro studies showed interleukin (IL)-1β expression to be elevated in SLA-matched and SLA-mismatched groups. Conclusion Cloned pigs are a useful preclinical model to evaluate the immunogenicity of mtDNA encoding minor antigens. The mtDNA originating from nongenomic DNA induced cell-mediated immune rejection after kidney transplantation.

The design of a two-axis micromechanical angular rate sensor based on a vibrating gyroscope of R-R type is presented in this paper. The gyroscope is built with the use of “sandwich” scheme, which uses the magnetoelectric exciter of torsional oscillations of a silicon sensitive element, two feedback loops on measurement channels consisting of capacitive pickoffs, amplifiers and magnetoelectric torquers (MT). Design features of the device provide its operability in gas-filled chamber at atmospheric pressure. Digital systems designed for the resonance tuning of the device and the maintenance of constant amplitude of angular rate of pendulum oscillations are described. The systems compensating the device zero bias and generating the output signals based on the microcontroller are also considered. The reasons for occurrence of gyroscope zero bias, connected with manufacturing defects of torsional pendulum elastic suspension and magnetic systems, are analyzed, and recommendations are given for their compensation by using such procedures as adjusting magnetic system of the exciter of torsional oscillations, modifying the elastic elements and introducing a compensating signal in a feedback loop. The results of calculating an elastic micromechanical system, modeling a gyroscope motion are presented in the paper at various ways of forming a feedback loop, as well as results from experimental research of the micromechanical angular rate sensor under development.

Contents To stably maintain pregnancy, several genes are expressed in the uterus. In particular, the endometrial expression of genes encoding growth factors appears to play a key role in maternal–foetal communication. The previous studies characterized the endometrial expression kinetics of the genes encoding epidermal growth factor (EGF), its receptor (EGFR), transforming growth factor-alpha (TGF-α), amphiregulin (Areg), heparin-binding (Hb) EGF and calbindin-D9k (CaBP-9k) in pigs during implantation. Here, we further characterized the expression patterns of these molecules during the entire porcine pregnancy. Porcine uteri were collected at pregnancy days (PD) 12, 15, 30, 60, 90 and 110 and subjected to RT-PCR. EGF and EGFR showed similar expression patterns, being highly expressed around implantation and then disappearing. TGF-α and Areg expression levels rose steadily until they peaked at PD30, after which they gradually decreased to PD12 levels. This Areg mRNA expression pattern was confirmed by real-time PCR and similar Areg protein expression patterns were observed. Immunohistochemical analysis of PD60 uteri revealed Areg in the glandular and luminal epithelial cells. Hb EGF was steadily expressed throughout the entire pregnancy, while CaBP-9k was expressed strongly on PD12, and then declined sharply on PD15 before recovering slightly for the remainder of the pregnancy. Thus, the EGF family may play a key role during implantation in pigs. In addition, CaBP-9k may help to maintain uterine quiescence during pregnancy by sequestering cytoplasmic Ca2+.

The cryogenic system for the KSTAR superconducting (SC) magnets has been commissioned. It consists of a cold box, distribution boxes (DB) and cryogenic transfer lines. The cold box and DB #1 provide 600 g/s of supercritical helium to cool the SC magnets, their SC bus-lines, and the magnet support structures. It also provides 17.5 g/s of liquid helium to the current leads and supplies cold helium flow to the thermal shields. The main duties of the DB #2 are the relative distribution of the cryogenic helium among the cooling channels of each KSTAR cold component and the emergency release of over-pressurized helium during abnormal events such as quenches of the SC magnets. After individual commissioning, the system was integrated and cooled down with the KSTAR device. In this paper, the construction and commissioning results of the KSTAR cryogenic system will be introduced. In addition, we will present the cool-down results of the KSTAR device.

An 84-GHz, 500-kW electron cyclotron (EC) heating (ECH) system is under installation for ECH-assisted start-up in the Korea Superconducting Tokamak Advanced Research (KSTAR) facility. An 84-GHz, 500-kW gyrotron, and 1.5-MVA power supply system have been installed at KSTAR, and the initial test of the gyrotron has been carried out with a short-pulse condition of 20 μs and maximum beam parameters of 80 kV and 25 A that generate an output radio-frequency (rf) power of 500 kW. The planned 2-s-long operation with 500-kW rf output power is beginning with a long-pulse test of the gyrotron power supply. The launcher system was fabricated in collaboration with Princeton Plasma Physics Laboratory. It will inject 500-kW rf power into the KSTAR plasma with a highly flexible steering mirror system, allowing toroidal and poloidal beam deposition scans. KSTAR will employ 170-GHz EC current drive (CD) in ITER-relevant experiments such as the suppression of the neoclassical tearing modes and the creation of an electron internal transport barrier. The Japan Atomic Energy Agency will provide a 170-GHz, 1-MW gyrotron on loan in 2008 in accordance with a Korea-Japan fusion collaboration agreement, and it will be used for the 170-GHz, 1-MW ECCD system in 2010. This paper describes the current status of the installation and initial conditioning tests of the 84-GHz gyrotron system as well as the development plan of the 170-GHz ECH and CD system. Also, this paper discusses the CD efficiency and the steering range of the second-harmonic X-mode injection at 170 GHz and 5 MWfrom an equatorial launcher.

As a global pollutant, mercury (Hg) is of particular concern in East Asia where anthropogenic emissions are the largest. In this study, speciated Hg concentrations were measured in the western most island in Korea, located between China and the Korean mainland to identify the importance of local, regional and distant Hg sources. Various tools including correlations with other pollutants, conditional probability function, and back-trajectory based analysis consistently indicated that Korean sources were important for gaseous oxidized mercury (GOM) whereas, for total gaseous mercury (TGM) and particulate bound mercury (PBM), long-range and regional transport were also important. A trajectory cluster based approach considering both Hg concentration and the fraction of time each cluster was impacting the site was developed to quantify the effect of Korean sources and out-of-Korean source. This analysis suggests that Korean sources contributed approximately 55 % of the GOM and PBM while there were approximately equal contributions from Korean and out-of-Korean sources for the TGM measured at the site. The ratio of GOM / PBM decreased when the site was impacted by long-range transport, suggesting that this ratio may be a useful tool for identifying the relative significance of local sources vs. long-range transport. The secondary formation of PBM through gas-particle partitioning with GOM was found to be important at low temperatures and high relative humidity.

Conventional diagnostic methods for tuberculosis (TB) have limited sensitivity and specificity or are time-consuming.16S rDNA and 16S rRNA of Mycobacterium tuberculosis complex (MTC) were used as targets to develop sensitive and specific polymerase chain reactions (PCRs) to improve the diagnosis of MTC.We developed conventional and real-time PCRs targeting 16S rDNA and rRNA of MTC.PCRs targeting 16S rRNA had a 10-100 times lower limit of detection for M. tuberculosis than PCRs targeting 16S rDNA. The sensitivities of the 16S rDNA PCR, 16S rRNA reverse transcription PCR (RT-PCR), 16S rDNA real-time PCR and 16S rRNA real-time RT-PCR for sputum specimens were respectively 92%, 94.6%, 96% and 100%. Real-time PCR showed no cross-reactivity, but conventional PCR had cross-reactivity to M. avium, M. gastri and M. nonchromogenicum.PCRs targeting the 16S rRNA of MTC were more sensitive than those targeting 16S rDNA; 16S rRNA real-time RT-PCR showed the highest sensitivity and specificity for MTC.

An electrochemical sensor is built using vertically grown multi-walled carbon nanotubes (MWNTs) micro-array to detect methanol concentration in water. This study is done for the potential use of the array as methanol sensor for portable units of direct methanol fuel cells (DMFCs). Platinum (Pt) nanoparticles electro-deposited CNTs (Pt/CNTs) electrode shows high sensitivity in the measurement of methanol concentration in water with cyclic voltammetry (CV) measurement at room temperature. Further investigation has also been undertaken to measure the concentration by changing the amount of the mixture of methanol and formic acid in water. We compared the performance of our micro array sensor built with Pt/CNTs electrodes versus that of Pt wire electrode using CV measurement. We found that our Pt/CNTs array sensor shows high sensitivity and detects methanol concentrations in the range of 0.04 M to 0.10 M. In addition, we found that co-use of formic acid as electrolyte enables us to measure up to 1.0 M methanol concentration.

An electrochemical sensor is built using vertically grown multi-walled carbon nanotubes (MWNTs) micro-array to detect methanol concentration in water. This study is done for the potential use of the array as methanol sensor for portable units of direct methanol fuel cells (DMFCs). Platinum (Pt) nanoparticles electro-deposited CNTs (Pt/CNTs) electrode shows high sensitivity in the measurement of methanol concentration in water with cyclic voltammetry (CV) measurement at room temperature. Further investigation has also been undertaken to measure the concentration by changing the amount of the mixture of methanol and formic acid in water. We compared the performance of our micro array sensor built with Pt/CNTs electrodes versus that of Pt wire electrode using CV measurement. We found that our Pt/CNTs array sensor shows high sensitivity and detects methanol concentrations in the range of 0.04 M to 0.10 M. In addition, we found that co-use of formic acid as electrolyte enables us to measure up to 1.0 M methanol concentration.

The mission of Korea Superconducting Tokamak Advanced Research (KSTAR) project is to develop an advanced steady-state superconducting tokamak for establishing a scientific and technological basis for an attractive fusion reactor. Because one of the KSTAR mission is to achieve a steady-state operation, the use of superconducting coils is an obvious choice for the magnet system. The KSTAR superconducting magnet system consists of 16 Toroidal Field (TF) coils and 14 Poloidal Field (PF) coils. Internally-cooled Cable-In-Conduit Conductors (CICC) are put into use in both the TF and PF coil systems. The TF coil system provides a field of 3.5 T at the plasma center and the PF coil system is able to provide a flux swing of 17 V-sec. The major achievement in KSTAR magnet-system development includes the development of CICC, the development of a full-size TF model coil, the development of a coil system for background magnetic-field generation, the construction of a large-scale superconducting magnet and CICC test facility. TF and PF coils are in the stage of fabrication to pave the way for the scheduled completion of KSTAR by the end of 2006.

As there is substantial progress in the KSTAR tokamak engineering, all the major structures and sub-systems are under fabrication and in procurement phase. The vacuum vessel, port, cryostat cylinder, lid, and bellows are being rigorously fabricated in the factory. The lower part of the KSTAR such as cryostat base and gravity support has been almost finished in its fabrication. There are also great progresses and significant results in manufacturing of the superconducting magnet, including four Toroidal Field (TF) coils, lower and upper PF7 coils which are the largest Poloidal Field (PF) coils. The TF00 coil, which has been made for test and back-up of the TF magnet system, was successfully tested in the cool-down and current charging. As the fabrications and procurements of major structures have been actively proceeded, assembly works were also launched from Aug. 2003. More detailed description on these status, results, and plans will be described in this paper.

A magnet-supporting post installed between the lower TF coil cooled by 4.5 K supercritical helium and the cryostat base is one of the most important components of the superconducting magnet-supporting structure for KSTAR Tokamak. This structure should be flexible to absorb thermal shrink of the magnet and should also be rigid to support the magnet weight and the plasma disruption load. The post was designed with stainless steel (SS) 316 LN and carbon fiber reinforced plastic (CFRP) that has low thermal conductivity and high structural strength at low temperature. In order to verify the fabricability and the structural safety, a whole scale prototype of the KSTAR magnet-supporting post was manufactured and tested. Both static and compressive cyclic load tests under the maximum plasma vertical disruption load and the magnet dead weight were performed. The test results showed that the magnet-supporting post of KSTAR Tokamak was fabricable and structurally rigid.

The surface of the insect stages of the protozoan parasite Trypanosoma brucei is covered by abundant glycosyl phosphatidylinositol (GPI)-anchored glycoproteins known as procyclins. One type of procyclin, the EP isoform, is predicted to have 22–30 Glu-Pro (EP) repeats in its C-terminal domain and is encoded by multiple genes. Because of the similarity of the EP isoform sequences and the heterogeneity of their GPI anchors, it has been impossible to separate and characterize these polypeptides by standard protein fractionation techniques. To facilitate their structural and functional characterization, we used a combination of matrix-assisted laser desorption ionization and electrospray mass spectrometry to analyze the entire procyclin repertoire expressed on the trypanosome cell. This analysis, which required removal of the GPI anchors by aqueous hydrofluoric acid treatment and cleavage at aspartate-proline bonds by mild acid hydrolysis, provided precise information about the glycosylation state and the number of Glu-Pro repeats in these proteins. Using this methodology we detected in a T. bruceiclone the glycosylated products of the EP3 gene and two different products of the EP1 gene (EP1-1 and EP1-2). Furthermore, only low amounts of the nonglycosylated products of theGPEET and EP2 genes were detected. Because all procyclin genes are transcribed polycistronically, the latter finding indicates that the expression of the GPEET andEP2 genes is post-transcriptionaly regulated. This is the first time that the whole procyclin repertoire from procyclic trypanosomes has been characterized at the protein level.

One of the major difficulties in neural network applications is the selection of the parameters in network configuration and the coefficients in learning rule for fast convergence. This paper develops a network design by combining the Taguchi method and the back-propagation network with an adaptive learning rate for minimum training time and effective vibration suppression. Analyses and experiments show that the optimal design parameters can be determined in a systematic way thereby avoiding the lengthy trial-and-error.

The Hanbit magnetic mirror device, which is operated as a joint plasma research facility, has been constructed at Korea Basic Science Institute for basic study and technology development of high te...

To conduct plasma research with a steady-state high magnetic field, a magnetic mirror system with a pair of superconducting magnets (SCMs), named Superconducting Magnet Plasma Research Facility (SPRF), is under development. Major components of the system are a pair of NbTi solenoid SCMs, two cryostats, a plasma chamber, and a dc power supply. Each SCMs is separated by 1-m distance and operated at 800 A. The magnetic flux density on the axis of the SPRF is 0.23 T at the mid point and 3.1 T at the magnet center, which gives the mirror ratio of 13.4. In this paper, we describe the design consideration of SPRF, including the development activities of the magnets and the cryostats. Also, the test results of the magnets and the cryostats are described.

We report the plasma production experiment in the central cell of the Hanbit device. In the experiment, an RF wave is excited by a slot antenna with a driving frequency of 3.75 MHz, and the RF power is applied up to 200 kW with a flat-top pulse length of 100 ms. The reproducible plasmas are produced without preionization with an averaged density of 2×10 12 cm -3 . The power absorption characteristics of the slot antenna are investigated by measuring the plasma resistance. The measured value of plasma resistance is in the range of 0.2 to 1.2 Ω. The discharges show transitions of the plasma density as the RF power increases.

An optimal neural network design is to select the network configuration and the learning rule for fast convergence and best system performance. This paper develops a network design methodology so that the optimal design can be determined in a systematic way. The methodology combines the Taguchi method of quality engineering and the back-propagation network with an adaptive learning rate for their advantages in implementation feasibility and performance robustness. Vibration suppression experiments of a composite smart structure with embedded piezoelectric sensor/actuator validate that the methodology provides an efficient neural controller design, including the plant order, the number of hidden layer neurons, the number of training patterns, and the coefficients of adaptive learning rate.

Smart structure with build-in sensor(s) and actuator(s) that can actively and adoptively change its physical geometry and properties has been considered one of the best candidates in vibration control applications. Implementation of neural networks to system identification and vibration suppression of a smart structure is conducted in this paper. Three neural networks are developed, one for system identification, the second for on-line state estimation, and the third for vibration suppression. It is shown both in analysis and in experiment that these neural networks can identify, estimate, and suppress the vibration of a composite structure by the embedded piezoelectric sensor and actuator. The controller is also shown to be robust to system parameter variations.

In supraoptic nucleus (SON) magnocellular neurosecretory cells (MNCs), γ-GABA, via activation of GABAA receptors (GABAA Rs), mediates persistent tonic inhibitory currents (Itonic ), as well as conventional inhibitory postsynaptic currents (IPSCs, Iphasic ). In the present study, we examined the functional significance of Itonic in SON MNCs challenged by 24-h water deprivation (24WD). Although the main characteristics of spontaneous IPSCs were similar in 24WD compared to euhydrated (EU) rats, Itonic , measured by bicuculline (BIC)-induced Iholding shifts, was significantly smaller in 24WD compared to EU rats (P < 0.05). Propofol and diazepam prolonged IPSC decay time to a similar extent in both groups but induced less Itonic in 24WD compared to EU rats, suggesting a selective decrease in GABAA receptors mediating Itonic over Iphasic in 24WD rats. THIP (4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol), a preferential δ subunit agonist, and L-655,708, a GABAA receptor α5 subunit selective imidazobenzodiazepine, caused a significantly smaller inward and outward shift in Iholding , respectively, in 24WD compared to EU rats (P < 0.05 in both cases), suggesting an overall decrease in the α5 subunit-containing GABAA Rs and the δ subunit-containing receptors mediating Itonic in 24WD animals. Consistent with a decrease in 24WD Itonic , bath application of GABA induced significantly less inhibition of the neuronal firing activity in 24WD compared to EU SON MNCs (P < 0.05). Taken together, the results of the present study indicate a selective decrease in GABAA Rs functions mediating Itonic as opposed to those mediating Iphasic in SON MNCs, demonstrating the functional significance of Itonic with respect to increasing neuronal excitability and hormone secretion in 24WD rats.

In the case of internal gear pumps, the eccentricity of the outer rotor, which resembles a circular lobe, must be limited to a certain value in order to avoid the formation of cusps and loops; furthermore, the tip width of the inner rotor, which has a hypocycloid curve and an epicycloid curve, should not be allowed to exceed the limit value. In this study, we suggest that the tip width of the inner rotor be controlled by inserting a circular-arc curve between the hypocycloid and epicycloid curves. We also suggest that the outer rotor be designed using the closed-form equation for the inner rotor and the width correction coefficient. Thus, it is possible to design a gerotor for which there is no upper limit on the eccentricity, as in this case, undercut is prevented and there is no restriction on the tip width. We also develop an automated program for rotor design and calculation of the flow rate and flow rate irregularity. We demonstrate the superior performance of the gerotor developed in this study by analyzing the internal fluid flow using a commercial computational fluid dynamics (CFD)-code.

The purposes of the Lawrence Livermore National Laboratory Environmental Report 2010 are to record Lawrence Livermore National Laboratory's (LLNL's) compliance with environmental standards and requirements, describe LLNL's environmental protection and remediation programs, and present the results of environmental monitoring at the two LLNL sites - the Livermore site and Site 300. The report is prepared for the U.S. Department of Energy (DOE) by LLNL's Environmental Protection Department. Submittal of the report satisfies requirements under DOE Order 231.1A, Environmental Safety and Health Reporting, and DOE Order 5400.5, Radiation Protection of the Public and Environment. The report is distributed electronically and is available at https://saer.llnl.gov/, the website for the LLNL annual environmental report. Previous LLNL annual environmental reports beginning in 1994 are also on the website. Some references in the electronic report text are underlined, which indicates that they are clickable links. Clicking on one of these links will open the related document, data workbook, or website that it refers to. The report begins with an executive summary, which provides the purpose of the report and an overview of LLNL's compliance and monitoring results. The first three chapters provide background information: Chapter 1 is an overview of the location, meteorology, and hydrogeologymore » of the two LLNL sites; Chapter 2 is a summary of LLNL's compliance with environmental regulations; and Chapter 3 is a description of LLNL's environmental programs with an emphasis on the Environmental Management System including pollution prevention. The majority of the report covers LLNL's environmental monitoring programs and monitoring data for 2010: effluent and ambient air (Chapter 4); waters, including wastewater, storm water runoff, surface water, rain, and groundwater (Chapter 5); and terrestrial, including soil, sediment, vegetation, foodstuff, ambient radiation, and special status wildlife and plants (Chapter 6). Complete monitoring data, which are summarized in the body of the report, are provided in Appendix A. The remaining three chapters discuss the radiological impact on the public from LLNL operations (Chapter 7), LLNL's groundwater remediation program (Chapter 8), and quality assurance for the environmental monitoring programs (Chapter 9). The report uses System International units, consistent with the federal Metric Conversion Act of 1975 and Executive Order 12770, Metric Usage in Federal Government Programs (1991). For ease of comparison to environmental reports issued prior to 1991, dose values and many radiological measurements are given in both metric and U.S. customary units. A conversion table is provided in the glossary.« less

The ITER coil power supplies provide controlled DC current to charge and stabilize the current in a toroidal field (TF) coil, and to establish and control the currents in a central solenoid (CS) module, poloidal field (PF) coils, and correction coils (CC) for the position and shape control of plasma. They consist of different types of AC/DC converters to meet the various operating requirements. The controller design for ITER AC/DC converters is based on the plant control design handbook as an ITER design guideline. There are basically three networks such as CODAC (COntrol, Data Access and Communication) network, central interlock network, central safety network for ITER instrumentation and control. Korean Domestic Agency has been being performing converter R&D to establish the technical basis for the procurement package of ITER AC/DC converter. The R&D on converter controller is under progress to implement a real time control and monitoring, interlock for equipment protection and emergency shutdown, personnel safety. The dynamic control algorithm to realize a fast response with high fidelity, high speed real time control, communication hardware and configuration are key issues. ITER converters are simulated by small-scaled test bed for AC/DC converters controlled by a CODAC simulator using a cPCI (compactPCI), a fast controller using a cPCI, a Plant System Host and a Siemens S7-300 PLC. The small-scaled test bed has an embedded controller based on digital signal processing and field-programmable gate array technology. This paper shows the detail description of the test bed and test results of the real time control and monitoring, sequential control, circulating current mode, etc.

The CuIn1‐xGaxSe2 (CIGS) solar cells show a good spectral response in a wide range of the solar spectrum and the bandgap of CIGS. It can be adjusted from 1.0 eV to 1.7 eV by increasing the gallium‐to‐indium ratio of the absorber. Generally, the co‐evaporator method have used for development and fabrication of the CIGS absorption layer. However, this method should need many steps and lengthy deposition time with high temperature. For these reasons, in this paper, a new growth method of CIGS layer was attempted to mixed source pellet method. The CIGS absorber layer was deposited for using by E‐beam evaporator on the ITO glass substrate. For crystallization of CIGS thin film, we measured SEM, EDS and XRD.

CuInGaSe(CIGS) mixed‐source was prepared by hydride vapor transport method (HVT). The new source synthesis method was attempted by mixing several metals such as Cu, In, Ga and Se with 3:5:1:4 mass ratios. This mixed‐source was soaked at 1090 °C for 90 minutes in nitrogen atmosphere. After grinding the mixed‐source to powder, the shape of pellet was made by casting. The horizontal type HVT system was used for the growth of CIGS layer. The HCl gas was flowed over CIGS source and its flow rate was 60 sccm. The temperature of source zone and growth zone were 650 °C and 750 °C, respectively. The growth time was about 4 hours. The EDS result shows that the composition of the Cu, In, Ga, and Se were 8.64 %, 5.62 %, 11.81 %, and 73.93 %, respectively. We suggest that the newly fabrication method of CIGS compound semiconductor for solar cell device was prepared by HVT method.

In this study, we investigate the trap‐based memory characteristics at sub‐5 nm silicon nitride layer in the conventional oxide‐nitride‐oxide capacitors. As a result, based on the experimental data, sub 5‐nm storage layer has considerable charge trapping capability and thus embodies nonvolatile memory operation.

Two types of largest subunit RNA polymerase II (pol II) genes (pol IIA and pol IIB), differing in 3 amino acid substitutions, are encoded in the Trypanosoma brucei (stock 427-60) genome. As a result, the alpha-amanitin-resistant transcription of the procyclic acidic repetitive protein (PARP) and variant surface glycoprotein (VSG) genes was proposed to involve a modified, alpha-amanitin-resistant form of the largest subunit of pol II. Alternatively, pol I could transcribe the PARP and VSG genes. To discriminate between these two models, we deleted the N-terminal domain (about one-third of the polypeptide), which encodes the amino acid substitutions which discriminated the pol IIA and pol IIB genes, at both pol IIB alleles. The pol IIB- trypanosomes still transcribe the PARP genes and the VSG gene promoter region in insect-form trypanosomes by alpha-amanitin-resistant RNA polymerases, while control housekeeping genes are transcribed in an alpha-amanitin-sensitive manner, presumably by pol IIA. We conclude that the alpha-amanitin-resistant transcription of protein coding genes in T. brucei is not mediated by a diverged form of the largest subunit of pol II and that the presence of both the pol IIA and pol IIB genes is not essential for trypanosome viability. This conclusion was further supported by the finding that individual trypanosome variants exhibited allelic heterogeneity for the previously identified amino acid substitutions and that various permutations of the polymorphic amino acids generate at least four different types of largest subunit pol II genes. The expression of the PARP genes and the VSG gene promoter region by alpha-amanitin-resistant RNA polymerases in the pol IIB- trypanosomes provides evidence for transcription of these genes by pol I.

The influence of temperature on tuber yield and development of internal heat necrosis (IHN) in Atlantic (Solanum tuberosum L.) was examined in field trials in two locations over three years (seven plantings). Under simulated commercial production, yield and development of IHN varied significantly between Virginia (VA) and New Jersey (NJ) in 1986, 1987, and 1988. Marketable yield ranged from 49.8 mt.ha−1 for the early planting in 1986 in New Jersey (NJ86E) to 17.9 for VA87. Tubers developing IHN to a level which potato chip processors would rate unacceptable (off-grade) varied with year and location. Significant correlations were found between the number of days to off-grade and the mean maximum temperature for 0–30 (r = −.83), 30–60 (r = −.86) and 60–90 DAP (r = −.81) as well as the mean minimum temperature for the same periods (r = −.91,, −.80 and −.91, respectively). The relationship between yield or IHN and temperature was examined using heat-sum models with a penalty for maximum daily temperature > 25C but with or without a penalty for minimum temperature > 21C. The multiple coefficients of determination for yield were similar using either variables generated from the heat-sum model with maximum and minimum temperature penalties or from the model with maximum temperature penalty only (R2 = 0.83 and R2 = 0.82). The prediction of the time from first symptom of necrosis to off-grade (interval) was improved by including variables generated by the heat-sum model that included both the minimum and maximum temperature penalty (R2 = 0.50 vs. R2 = 0.27), respectively. High minimum temperatures as reflected in the days to maximum heat-sum were found to significantly affect tuber yield and the expression and development of IHN.