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Recently, as the damage of air pollution due to fine dusts, etc. has been continuously increased, there is a growing need for a low-cost air quality monitoring system to observe air pollution information at public facilities or homes. In this paper, we propose an IoT (Internet of Things)-based atmospheric environment monitoring system which can effectively observe air pollution information without restriction of place or space. The proposed system consists of an atmospheric environment measuring device and an atmospheric environment analyzer, in which the system has been developed to be able to collect and analyze atmospheric environment measurement results in a server through an LTE communication network. The atmospheric environment information obtained from the development system was compared with the observation results provided by the National Ambient air quality Monitoring Information System (NAMIS).

The high-NA angle-resolved scatterometer YieldStar 1250D, with a small 12x12μm2 inspection area, has been used to inspect CD variation After Develop (ADI) and After Partition/Final Etch (APEI/AFEI) on various layers and features of a HVM DRAM process. During recipe set-up, CD-SEM data were used to verify full recipe quality. The high sampling density enabled by the small inspection area and high speed of the YieldStar angle-resolved scatterometer could be used to reveal various kinds of CD variations. An intra-field control-loop with scanner dose corrections was tested, using very dense ADI and APEI measurements, 400ppf, 4fields. This strategy demonstrated a 21% improvement in intra-field CDU, in line with expectations from predictions. Inter-field control loops with different strategies have been simulated for APEI CD control. To capture all variations in the inter-field fingerprints a dense sampling, 24ppf full wafer, in combination with a dynamic, context-based control strategy, appeared to be necessary. An improvement of 30% of the wafer CDU (excluding the intra-field) is feasible. For the Self-Aligned Double Patterning process, essential for the dense DRAM cells, the CD variation at APEI contributes to pitch-walking at final etch. Pitch walking is an alternating OV error, therefore these control strategies will also contribute to improvement of the OV control budget.

In order to optimize yield in DRAM semiconductor manufacturing for 2x nodes and beyond, the (processing induced) overlay fingerprint towards the edge of the wafer needs to be reduced. Traditionally, this is achieved by acquiring denser overlay metrology at the edge of the wafer, to feed field-by-field corrections. Although field-by-field corrections can be effective in reducing localized overlay errors, the requirement for dense metrology to determine the corrections can become a limiting factor due to a significant increase of metrology time and cost. In this study, a more cost-effective solution has been found in extending the regular correction model with an edge-specific component. This new overlay correction model can be driven by an optimized, sparser sampling especially at the wafer edge area, and also allows for a reduction of noise propagation. Lithography correction potential has been maximized, with significantly less metrology needs. Evaluations have been performed, demonstrating the benefit of edge models in terms of on-product overlay performance, as well as cell based overlay performance based on metrology-to-cell matching improvements. Performance can be increased compared to POR modeling and sampling, which can contribute to (overlay based) yield improvement. Based on advanced modeling including edge components, metrology requirements have been optimized, enabling integrated metrology which drives down overall metrology fab footprint and lithography cycle time.

We investigated pseudo-Josephson current effects in magnetite. Compared with the original Josephson junctions applied to superconductors, we obtained theoretical results that correlate well with experimental current data. Even though we applied a pseudo-Josephson junction to the current along the axis of energy (i.e. the momentum space), the theoretical form of DC-type currents was proportional to a tan function for the time parameter or a tanh function for the temperature parameter, which agrees with the experimental data. These pseudo-Josephson junctions occur in momentum space rather than in real space. The currents in magnetite are not primarily due to the electron–phonon interactions that induce a gap opening in band structures. We hypothesize that the Verwey Transition (VT) mechanism is pseudo-Josephson in nature.

Spin density waves (SDWs) may be thought of as comprising charge density waves (CDWs) in pairs, with one CDW composed of up-spin electrons and the other composed of down-spin electrons. The superconductivity in cuprates may then be said to be caused by the BCS-type pairing of these SDWs. This is no longer a simple Cooper pairing of singlet electrons but one that involves a collection of Cooper pairs. Transport in normal metallic states is then governed by CDW pinning, as in a quantum well that is characterized by linear temperature dependence. The pseudo-gap may be understood as originating from this BCS-type gap with SDW, where the parameters used are from those of the original BCS scheme except that the electron–electron interaction is multiplied by N CDW , which is the number of electrons that have the same spin direction belonging to one CDW branch of the pair that comprises the SDW.

The propagation velocity of light emission is observed to be up ~0.92 times10+5 m/s along a tube of an inner diameter ro ~1.5 times10-3 m with an external electrode fluorescent lamp filled with 97% Ne and 3% Ar at a total pressure of 30 torr, a mercury-free lamp without phosphor coating the inside glass wall. The origin of this propagation is shown to be ambipolar diffusion with a plasma diffusion speed of up ~ (4.8/ro)Da for diffusion coefficient Da along the positive column. When a high voltage magnitude is applied at the external electrode, a high-density plasma is generated inside the hollow electrode, and the plasma diffuses along the positive column toward the ground electrode.

The different degrees of blackening were observed at the inner surface of borosilicate, soda-lime, and aluminosilicate glass tubes having different sodium (Na) contents. The sodium contents () within the borosilicate, soda-lime, and aluminosilicate glass tubes were found to be 4%, 14%, and 0.06%, respectively. The degree of blackening was shown to increase as the sodium content within the glass of the fluorescent lamp containing Ne+Ar+Hg gas mixture. Higher degree of blackening was observed from the inner surface of the glass tube coated with . The blackening was found to be originated from the amalgam of generated by the chemical reaction between the mercury ions within the discharge gas and sodium within the glass tube during operation.

The amount of vapor mercury for the generation of glow discharge plasma has been calculated in a fine tube fluorescent lamp having a mixed gas of Ne+Ar including a mercury. When the ionization of atom is considered by the collision between neutral atoms (Ne, Ar, Hg) and electrons of energy , the density of vapor mercury atom has been obtained as for the plasma density . In the fluorescent lamps of out diameter 4 mm used for -inch LCD-TVs having a mixture gas of Ne(95%)+Ar(5%) with the pressure of 50 Torr, the quantity of vapor mercury for the glow discharge has been caculated as .

Luminance properties of external electrode fluorescent lamps and optical components in backlight unit (BLU) and optical transmission rates of optical sheets, are investigated for LCD-TV of 32" in diagonal with WXGA level resolution (1366768). The luminance is measured in 12-lamps and 18-lamps of BLU. The luminance uniformity preserves about 85 % in the 12-lamps backlight, while the luminance of optical components and the efficiency of backlight in the 12-lamps are lower than those in the 18-lamps backlight. When the lamp luminance in BLU having 12-lamps and 18-lamps is normalized as 100 %, the relative luminance of a diffusion plate, a diffusion sheet, a prism sheet (BEF), a polarization sheet (DBEF), has a constant value without dependence on a lamp luminance. The relative luminance of optical components in 12-lamps BLU is lower than that in 18-lamps backlight. The light transmission rate, the relative luminance of liquid crystal display panel with the luminance 100 % of backlight, is 7.14 % in the use of DBEF and BEF, 6.12 % in the use of only DBEF, and 3.21 % in the use of only BEF. Those Data obtained in this experiment for the lamps and optical components, are the design parameters for the LCD backlight.

Influence of glass dielectric property (dielectric constant K, dielectric loss) on the external electrode fluorescent lamps of the dielectric barrier discharge has been investigated with 4-different glasses. Conventional borosilicate glass tubes with $K

A new non-invasive method for the determination of electron drift velocity has been investigated by measuring the light propagation signals in external electrode fluorescent lamps with two usual operation methods. At the luminance of 12 000 cd m−2 with an operation frequency of 65 kHz, the electron drift velocity in accordance with the propagation speed of light emission is measured to be 2.72 × 105 m s−1. From the electron drift velocity, the electron temperature and the plasma density in the positive column are estimated to be kTe ~ 1.6 eV and ne ~ 4.3 × 1016 m−3, respectively, which agree well with data in the glow discharge plasma of typical fluorescent lamps.

From the light propagation observed along the tube of CCFLs and EEFLs, the electron temperature and the plasma density are estimated as kTe∼2 eV and ne∼1016 m−3. This might be a new diagnostic technology to measure the plasma parameters in the fine tube of gas discharge.

The efficiency of EEFLs with the new glass tube of high dielectric constant K∼6.6 and low dielectric loss tan δ, reaches 45 lm/W which is ∼ 20 % higher than 38 lm/W in the conventional glasses of K ∼ 5.5. And this new glass tube EEFL also shows a high reliability against pinholes.

The commercialized EEFL-BLUs of 32″, 37″, and 42″ LCD-TVs are reported with respect to the basic characteristics of luminance and efficiency. The capacitive and resistive reactance is also presented to design the inverter for lamps and BLUs.

We present a mechanism that explains currents in solar cells using charge density wave (CDW) concepts. We treated pinned CDWs as being equivalent to moving CDWs that have been confined within a typical quantum well, using the many different examples where pinning occurs at the barrier. The currents in the solar cells are not described in terms of the unique semiconductor difference between electrons and holes, but are instead explained by making use of pinned CDWs in terms of the electrons contained therein, with a potential barrier that is lower than the energy gap in the solar cell material. The mechanism of the function of the solar cell is thus herein ascribed to the transport of pinned CDWs. The functions of solar cells are indispensable with impurities in the case of our CDW model different from conventional explanation.

Pd thin films and Co/Pd multilayered films with progressively thicker Pd underlayers are prepared by physical vapor depositions. Their growth behaviors are investigated using atomic force microscopy and transmission electron microscopy. We observed that a mound occurs on top of each crystallite of (111) oriented polycrystalline Pd films and that the average mound size increases according to the capillary-induced coalescence mechanism. We attribute this observed growth instability to the step barrier which resists step-down diffusion of deposited atoms. We also observed that the mound slopes of Co/Pd multilayers are smaller than those of their Pd underlayers. We suggest that this results from a downhill current driven by the interface energy between the Co and Pd layers.

Using x‐ray photoelectron spectroscopy (XPS), W 4f core level spectra of electrochromic HxWO3 films have been investigated as a function of the injected charge. W 4f peaks become broader with increasing injected charge. The line shape analysis of W 4f XPS spectra of amorphous HxWO3 films reveals that each spin‐orbit split component consists of two peaks. It is also found that, as the injected charge increases, the intensity of the low binding energy (BE) peaks, the asymmetry factor of core lines, and the intrinsic lifetime width increase systematically. Composite structures of W 4f peaks have been attributed to the existence of the different final states, screened by different numbers of W 5d electrons. The low BE peaks are considered to correspond to the locally screened final states, with one more W 5d electrons than in the ground state, which arise from midgap state conduction electrons near EF. There is also a possibility that a mixture of fine scale phases contributes to composite structures and broader linewidths in HxWO3.

Plasma enhanced chemical vapor deposition (PECVD) and crystallization of amorphous-Si (a-Si) by post-annealing are used in the formation of poly-Si films. In respect of a low-price glass plate as the substrate of flat panel display (FPD), the current issues of annealing systems are a good uniformity, a large area capability, and a low-temperature processing, and a fast annealing time. One of the challenging technologies is the xenon flash lamp (XFL) annealing.

The plasma purification of air-pollution is studied with the flowing gases of automobile exhaust fumes and chimney smokes.

Polycrystalline silicon (poly-Si) film is widely used for silicon-gate metal oxide semiconductor (MOS) integrated circuits, solar cells, thin-film transistors (TFTs). Amorphous silicon (a-Si) films formed by plasma enhanced chemical vapor deposition (PECVD), are crystallized to be poly-Si films by annealing, such as solid-phase crystallization, pulsed XeCl excimer laser annealing (ELA), and xenon flash lamp (XFL) annealing. In the annealing processes of XFL, it is a large area capability about 1 m, and a low-temperature processing, and a fast annealing time, required for the inexpensive glass plate as the substrate of flat panel display (FPD). However, it also has the limitation of lamp length since the uniformity and the operation conditions become worse as the gap distance between two electrodes increases in the arc discharge.

EEG based brain computer interface has provided a new communication pathway between the human brain and the computer. It can be used for handicap or disabled users to interact with human using the computer interface. It can also be used in controlling human's muscles movement. In this paper, we show that meaningful information can be extracted from EEG signal through incremental approach. We applied principal component analysis incrementally which recognizes patterns in the series of EEG data that consists of actual and imaginary limb movements. Our experiments have proven that the approach is promising especially in time series data because it works incrementally.

The electric circuit of backlight operation has been analyzed with respect the impedance matching between the backlight of external electrode fluorescent lamps and a transformer of inverter. The resistance and capacitance of the system has been determined from phase difference between current and voltage and a Q-V Lissajous' graph from oscilloscope signals. The coupling coefficient and inductance of the primary and secondary coils of the transformer has been introduced using LRC meter. Analytic solution of the impedance matching frequency are well in agreement with the experimental results.

Summary form only given, as follows. Summary form only given. Platinum(Pt) is a biocompatible material which exhibits strong thermal and electrical conductivity due to its high melting point and good durability And thus it is used commonly in bio-electrodes and bio-chips. Tungsten (W) wire was coated with platinum film, and analyzed for their mechanical and biocompatibility properties. Platinum film has been deposited by magnetron sputter with unbalanced magnetic field system (UBM) experiment was performed under a variety of conditions by changing deposition temperature, bias voltage, magnetic field and deposition time in order to deduce the optimum process We examined exfoliation and sedimentation state of anode and cathode by microscope and EPMA under the test of electro-chemical corrosion using Hank's solution and analyzed the film surface by AES survey and depth profile Film adhesion was analyzed by micro scratch tester Cross-section and diffraction was analyzed by SEM and XRD. Film showed very low impurity level, and surface and cross-section of the film is elaborate It also did not have sedimentation in film, and the crystallization in [110], [200], [220] and [222] was observed. However at high current density (800mA/cm/sup 2/) sedimentation was observed in corrosion test.

In this study, Co/Pd multilayered films with a few atomic layers of Co were prepared by alternating deposition in an ultrahigh‐vacuum physical‐vapor‐deposition system. The structural parameters were estimated accurately making use of only the angular positions of x‐ray diffraction peaks. The magnetic properties were found to vary greatly depending on Pd predeposition and Pd‐sublayer thicknesses as well as Co‐sublayer thickness. The Pd‐predeposited films were found to have a remarkably high coercivity of 4723 Oe and a greatly enhanced interfacial magnetic anisotropy of 0.72 mJ/m2, which indicates an excellent potential as a magneto‐optical recording medium.

The properties of longitudinal and transverse discharges are investigated with the use of external electrode tubular lamps, with respect to the characteristics of current and voltage, luminance and spectral radiation. With the mercury-rare gases, a high luminance of over 10 000 cd m−2 is readily obtained in the longitudinal discharge with a long positive column where the spectral radiations from Hg are dominant. However, the luminance is extremely low, a few hundred cd m−2, in the transverse discharge with a short gap where all kinds of atom species are ionized and the intensity of the spectral lines from Ne and Ar is rather high. With pure Xe and a mixture of Xe, the transverse discharge is superior to the longitudinal discharge in that the breakdown voltage is low and the luminance for a high pressure above 200 Torr is relatively high.

The propagation velocity of a light-emitting wave-front is observed to be u p∼2×10+5 m/s before Townsend breakdown and u p∼5×10+6 m/s after Townsend breakdown along a discharge tube of inner diameter r o∼1.2 mm and length of 900 mm relevant to liquid crystal display television backlighting. Before Townsend breakdown, the origin of this wave is the ambipolar diffusion of plasma flux with the propagation speed u p∝D a/r o for the plasma bounded by the radius r o with the diffusion coefficient D a along the positive column. After Townsend breakdown, the light-emitting wave-front propagates with the electron plasma wave generated by the pulses of driving voltage. The electron plasma wave propagates such a long distance along the tube without damping due to the effect of localized plasma generation by electron impact ionization collisions. The propagation velocity is described by u p∼2u e 2/u d, which is larger than the electron thermal velocity u e as well as the electron drift velocity u d.

In fluorescent lamp tubes, a few millimetres in radius, operating at several tens of kilohertz, the initiation of light radiation is characterized by the propagation of an electron plasma wave, accompanied by ionization caused by electron collision. Due to the effects of the ionization collision of electrons on the dispersion behaviour of the plasma waves, the electron plasma waves generated by the pulses of operation voltage, propagate along the positive column plasma without experiencing damping. The propagation velocity of radiated light, which represents the propagation of the electron plasma wave, can be higher than the electron thermal velocity.

The lamp length 0.6∼2.0 m of external electrode fluorescent lamps for the backlight of LCD-TVs has been investigated with respect to the lamp property, such as the current and voltage, the luminance and efficiency, and the luminance uniformity along the tube.

The origin of optical emission in a fine-tube fluorescent lamp is verified. The diffusion of plasma generated at a high voltage electrode, causes a radiation before Townsend discharge. At the normal glow, the propagation of electron plasma wave causes the light emission.

The optical propagation observed along the positive column of external electrode fluorescent lamps is shown to be an electron plasma wave propagating with the electron thermal speed of (kTe∕m)1∕2. When the luminance of the lamp is 10000–20000cd∕m2, the electron plasma temperature and the plasma density in the positive column are determined to be kTe∼1.26–2.12eV and no∼(1.28–1.69)×1017m−3, respectively.

Using the ionization rates of each atom species in a mixture gas of Ne(95%) + Ar(5%) + Hg(∼mg), the minimum quantity of mercury in the glow plasma discharge of CCFLs and EEFLs for a large area LCD backlight, is calculated to be 0.05 ∼ 0.36 mg without considering the mercury consumption.

External electrode fluorescent lamps of aluminosilicate glass with high dielectric constant, a low dielectric loss and a lowest sodium composition were compared with the conventional EEFLs of borosilicate and soda-lime glasses. The luminance efficiency increases by 15∼25 %, the pinhole stability improves remarkably, and the blackening of Hg-consumption is not observed.

A glass tube of aluminosilicate glass, with high dielectric constant K∼6.0 and low dielectric loss tan δ∼8.0×10−4, was investigated for the external electrode fluorescent lamps (EEFLs) of a dielectric barrier discharge. Compared with conventional EEFLs made out of borosilicate glass tubes with K∼(4.9−5.3) and tan δ∼(2.3−2.4)×10−3, the efficiency of the aluminosilicate EEFL increases by 15%−25% even at high luminance above 20 000 cd/m2 and the pinhole stability of the aluminosilicate EEFL also improves remarkably. In a soda-lime glass EEFL with a high dielectric loss tan δ∼7.0×10−3, the luminance and pinhole stability deteriorate even with a high dielectric constant K∼7.2 at room temperature, because the value of tan δ escalates as the temperature on the external electrode increases due to the dielectric heat dissipation.

The plasma propagation has been investigated by observing the optical signal along the tube of the EEFL for 32″ LCD backlight unit. The light starting from the electrode of high voltage moves toward the other side of electrode grounded electrically with the electron plasma propagation speed about 4×105 m/s.

The circuit of the inverter has been analyzed with EEFL-BLU for 32″ LCD-TV. The analytic solutions of a lamp current and a lamp voltage are compared with the experimental data with respect to the impedance matching with the inductance and the reactance of lamp system.