bluuebunny/crossref_metadata_2025 huggingface dataset:
A Survey of Register Labelling in Japanese Dictionaries: Towards the Labelling of Words in Dictionaries for Learners of Japanese
Authors: MAEBO Kanako
Published: March 2014

Writing by learners of Japanese as a foreign language often contains words that do not fit the style of their context. One possible reason for this is the lack of information on word connotation and usage labels in existing dictionaries. The present study examines the current state of connotational information and register labels in Japanese learner’s dictionaries, Japanese language dictionaries and dictionaries of synonyms, and proposes a possible technique for analysing the words’ descriptions. The study reveals that Japanese learner’s dictionaries and dictionaries for Japanese native speakers use different register labels and assign them from a different perspective. In the case of synonyms, presenting them in their context of use appears to be more useful than only listing them. Finally, the Balanced Corpus of Contemporary Written Japanese (BCCWJ - Gendai Nihongo Kakikotoba Kinkoo Koopasu) is used to show how corpora can be a very important linguistic resource for the analysis of lexical register.
Passives in South Asian Languages
Authors: CHANDRA Pritha , SAHOOA Anindita
Published: March 2014

Haspelmath (2010) debates whether universal (descriptive) categories of the types that generativists (cf. Newmeyer, 2007) envisage are real and needed for cross-linguistic studies. Instead every language has its own unique set of categories. We raise doubt on this “categorial particularism” position by drawing on underlying similarities of passive constructions of three South Asian languages - Oriya (Indo-Aryan), Malayalam (Dravidian) and Kharia (Austro-Asiatic). Unlike English-type passives, they retain subject properties for their logical subjects and object properties for their logical objects, suggesting commonalities that a “categorial particularism” approach would not allow us to posit. Our further contention is that like English passives, they too satisfy Shibatani’s (1985) minimal condition for passives – the underscoring or the optionality of agents. Passive voice must therefore be a universal found in all languages primarily resulting in the optionality of agents. We also show how adopting this approach helps us re-analyse Meitei and Ao (Tibeto-Burman) as languages involving passives.
Language Shift – The Case of Punjabi in Sargodha Region of Pakistan
Authors: NAZIR Barirah , AFTAB Umair , SAEED Ammara
Published: March 2014

This paper examines the linguistic scenario of Punjabi (second major language in Pakistan after Urdu) in Sargodha and the social mechanism which poses threat to the sustainability of Punjabi on a broader scale. It deals with the attitudes, causes and effects of the language shift from Punjabi to other languages due to prestige, modernity and social mobility issues. Triangulation (Questionnaires from n=80 and In-depth interviews from n=3) was used in order to observe the trends of shift. The findings exhibit that Punjabi speakers are not so loyal to their language, Punjabi language shift is a real not perceived phenomenon and a day may not be far away when Punjabi will be considered endangered language in Pakistan.
A Study of Rate of Speech and Intelligibility of Speech in Hearing impaired Pupils of Baghcheban School of Zahedan, Iran
Authors: SAEDI Mahla , ALAVI Fateme , SHEKARIAN BEHZADI Akram
Published: March 2014

Hearing loss results in disruption of coordination in muscles and structures engaged in speech timing tasks and consequently acquisition of speech sounds is affected. The purpose of this study is to investigate and compare the speed and intelligibility of speech in hearing impaired and normal hearing Persian speaking elementary school boys and girls. 33 hearing impaired students are randomly selected from three hearing impaired groups (profound, severe and moderately-severe) and compared with 60 normal hearing students. The speed of speech was measured according to reading Words Per Minute (WPM), and speech intelligibility was tested by a 5-rank scale method. As expected, the normal hearing had more speed and intelligibility of speech in contrast to the hearing impaired group. Also hearing impaired boys had a better speed and intelligibility of speech compared to hearing impaired girls but in normal hearing group, girls had better speed. The amount of P-value for moderately-severe and sever hearing impaired was 0.006 and this amount for profound and moderately-severe hearing impaired was 0.002, so p-value is <0.05 and significantly important. Profound hearing impaired group read the text more slowly and had lower speech intelligibility than other two hearing impaired groups.
Predation of threespine stickleback (Gasterosteus aculeatus) on the eggs of Atlantic herring (Clupea harengus) in a Baltic Sea lagoon
Authors: Kotterba Paul , Kühn Carsten , Hammer Cornelius , Polte Patrick
Published: March 2014

We analyzed the predation of threespine stickleback (Gasterosteus aculeatus) on the spawn of Atlantic herring (Clupea harengus) in a mesohaline lagoon of the Baltic Sea, hypothesizing a significant predation effect of a resident estuarine fish on the recruitment of an anadromous oceanic species. A predator exclusion field experiment using artificially spawned experimental units was combined with tank feeding experiments to estimate the effects of temperature and prey density on the herring egg consumption by estuarine G. aculeatus. The predator exclusion experiment showed a significant mortality of herring eggs caused by estuarine predatory fish species. A strong increase in the consumption of herring eggs by sticklebacks was observed between 11°C and 15°C (Q10 = 3.15). Additionally, we found a significant positive correlation between egg concentration per area and predation intensity. Nearly all eggs were consumed at concentrations ≥ 25 eggs cm−2, but predation was less intense at egg concentrations below that threshold. Field data on herring egg concentrations, stickleback abundances, and stomach contents were combined with the findings of the experiments to estimate the percentage of spawned herring eggs that is consumed by the local stickleback (MPS). The highest MPS (11.4%) was estimated for a week in April in the second half of the spawning season. We conclude that stickleback predation on herring eggs potentially affects the local herring year class strength.
The empirical relationship between satellite-derived tropospheric NO2 and fire radiative power and possible implications for fire emission rates of NOx
Authors: Schreier S. F. , Richter A. , Kaiser J. W. , Burrows J. P.
Published: March 2014

Abstract. Nitrogen oxides (NOx) play key roles in atmospheric chemistry, air pollution, and climate. While the largest fraction of these reactive gases is released by anthropogenic emission sources, a significant amount can be attributed to vegetation fires. In this study, NO2 from GOME-2 on board EUMETSAT's MetOp-A and OMI on board NASA's Aura as well as fire radiative power (FRP) from the measurements of MODIS on board NASA's Terra and Aqua satellites are used to derive fire emission rates (FERs) of NOx for different types of vegetation using a simple statistical approach. Monthly means of tropospheric NO2 vertical columns (TVC NO2) have been analyzed for their temporal correlation with the monthly means of FRP for five consecutive years from 2007 to 2011 on a horizontal 1° × 1° grid. The strongest correlation is found to be largely confined to tropical and subtropical regions, which account for more than 80% of yearly burned area, on average, globally. In these regions, the seasonal variation of fire intensity, expressed by the FRP data, is similar to the pattern of TVC NO2. As chemical models typically require values for the amount of NOx being released as a function of time, we have converted the retrieved TVC NO2 into production rates of NOx from fire (Pf) by assuming a constant lifetime of NOx. The comparison between Pf and NOx emissions from the Global Fire Emissions Database (GFEDv3.1) over 5 characteristic biomass burning regions in the tropics and subtropics shows good agreement. By separating the monthly means of Pf and FRP according to land cover type, FERs of NOx could be derived for different biomes. The estimated FERs for the dominating types of vegetation burned are lowest for open shrublands and savannas (0.28–1.03 g NOx s−1 MW−1) and highest for croplands and woody savannas (0.82–1.56 g NOx s−1 MW−1). This analysis demonstrates that the strong empirical relationship between TVC NO2 and FRP and the following simplified assumptions are a useful tool for the characterization of NOx emission rates from vegetation fires in the tropics and subtropics. Possible factors affecting the magnitude of the obtained values are discussed.
Investigating PAH relative reactivity using congener profiles, quinone measurements and back trajectories
Authors: Alam M. S. , Delgado-Saborit J. M. , Stark C. , Harrison R. M.
Published: March 2014

Abstract. Vapour and particle-associated concentrations of 15 polycyclic aromatic hydrocarbons (PAH) and 11 PAH quinones have been measured in winter and summer campaigns at the rural site, Weybourne in eastern England. Concentrations of individual PAH are relatively smaller than average concentrations measured previously at urban sites in the UK. The concentrations of PAH of the air masses originating from southern England and mainland UK are significantly larger than those from Eastern Europe and the North Atlantic, while quinone to parent PAH ratios show an inverse behaviour, being highest in the more aged North Atlantic polar air masses. While concentrations of 1,2-naphthoquinone decline from winter to summer, those of 1,4-naphthoquinone and anthraquinone increase suggesting a photochemical formation pathway. A comparison of congener concentration profiles measured at Weybourne with those from an urban source area (Birmingham) reveals differential losses at the rural site, especially evident in fluoranthene : pyrene ratios and consistent with the known rates of vapour phase reactions of 3 and 4 ring compounds with hydroxyl radical. The ratios of quinones to their parent PAH at Weybourne are greater than those in the urban source area indicating either more rapid loss processes for PAH, or formation of quinones during advection of the air mass, or probably both.
Skill in forecasting extreme ozone pollution episodes with a global atmospheric chemistry model
Authors: Schnell J. L. , Holmes C. D. , Jangam A. , Prather M. J.
Published: March 2014

Abstract. From the ensemble of stations that monitor surface air quality over the United States and Europe, we identify extreme ozone pollution events and find that they occur predominantly in clustered, multi-day episodes with spatial extents of more than 1000 km. Such scales are amenable to forecasting with current global atmospheric chemistry models. We develop an objective mapping algorithm that uses the heterogeneous observations of the individual surface sites to calculate surface ozone averaged over 1° by 1° grid cells, matching the resolution of a global model. Air quality extreme (AQX) events are identified locally as statistical extremes of the ozone climatology and not as air quality exceedances. With the University of California, Irvine chemistry-transport model (CTM) we find there is skill in hindcasting these extreme episodes, and thus identify a new diagnostic using global chemistry-climate models (CCM) to identify changes in the characteristics of extreme pollution episodes in a warming climate.
Sesquiterpenoids and Diterpenes from Chamaecyparis obtusa var. breviramea f. crippsii
Authors: Xu Jian , Zeng Guang-Zhi , Liu Yi-Mei , Chen Ke-Li , Sun Zhang-Hua , Zhang Yu-Mei , Tan Ning-Hua
Published: March 2014

Four new sesquiterpenoids, 1α-hydroxymethyl-3β-hydroxy-7,8-dihydro-ionol (1), 1α-hydroxymethyl- 3β-hydroxy-7,8-dihydro-ionol-9-O-β-D-glucopyranoside (2), (1α,5β,7β)-3,10(14)-guaiadien- 11,12-diol (3), and (6S)-13-O-β-D-glucopyranosyl-abscisic acid (4), together with 10 known sesquiterpenoids and 5 diterpenes were isolated from the branches and leaves of Chamaecyparis obtusa var. breviramea f. crippsii. Their structures were mainly determined on the basis of MS, IR, 1D and 2D NMR spectral evidence. Compound 13-epi-toruolsol (17) showed cytotoxicities against BGC-823 and Hela cancer cell lines with IC50 values of 23.0 and 49:9 μM, and compound 3-epitriptobenzene B (19) showed cytotoxicities against BGC-823, Hela and A549 cancer cell lines with IC50 values of 19.1, 30.3 and 24:5 μM, respectively
Orthoamide und Iminiumsalze, LXXXIII [1]. Die Synthese von starken Formylierungsmitteln im präparativen Großmaßstab: Triformamid (Triformylamin) / Orthoamides and Iminium Salts LXXXIII [1]. The Synthesis of Strong Formylating Reagents on Large Preparative Scale: Triformamide (Triformylamine)
Authors: Kantlehner Willi , Ziegler Georg , Scherr Oliver , Kreß Ralf , Leonhardt Sylvia
Published: March 2014

The preparation of sodium diformamide (7) from formamide and sodium methanolate under azeotropic removal of methanol with cyclohexane, or from formamide and sodium ethanolate in ethanol, is described. Diformamide (8) can be prepared by treatment of sodium diformamide (7) with formic acid. Triformamide (triformylamine) (1) is formed in the reaction of sodium diformamide with inorganic acid halides such as SOCl2, SO2Cl2 or PCl3 in acetonitrile at low temperatures. Triformamide (1) can be prepared on a large scale by the action of methanesulfonyl chloride on finely powdered sodium diformamide (7) in acetonitrile. Tris(diformylamino)methane (4) can be formed as a side product. A procedure was developed for the large-scale preparation of N;N-diformylacetamide (6) from sodium diformamide and acetyl chloride. Triformamide (1) can be prepared from N;Ndiformylacetamide (6) and diformamide with good yields
Crystal Structure and NMR Study of Tetrakis(acetonitrile)silver(I) Fluorosulfonate [Ag(CH3CN)4]+[SO3F]–
Authors: Dörtbudak Can-Carlo , Lux Karin , Kornath Andreas
Published: March 2014

The title compound [Ag(CH3CN)4]+[SO3F]- crystallizes in the orthorhombic space group Pna21, a = 24:383(24), b = 8:632(11), c = 20:755(17) Å, V = 4368(6) Å3, Z = 12, with three independent formula units in the unit cell. A comparison with the isostructural compound [Ag(CH3CN)4]+ [ClO4]- is given. The salt has also been characterized by solution 1H and 19F NMR spectroscopy and the data compared to that of fluorosulfonic acid
The New Ternary Silicide ErCo3Si2
Authors: Dzevenko Mariya , Bigun Inna
Published: March 2014

The new ternary silicide ErCo3Si2 adopts the ErRh3Si2 structure type (space group Imma, Pearson code oI24, Z = 4, a = 6:950(1), b = 9:020(2), c = 5:230(1) Å, R1 = 0:0565, wR2 = 0:0355, 253 F2 values, 23 variables). It is a deformation derivative of the CeCo3B2 structure type. The coordination of the Er atom shows a normal 20- vertex polyhedron [Er(Si6Co12Er2)]. The two similar coordination polyhedra of Co are a distorted icosahedron [Co(Si4Co4Er4)], and a distorted icosahedron with one capped face [Co(Si4Co5Er4)]. The Si atom is surrounded by the polyhedron [Si(Co6Si2Er3)]
Different Structural Models of YB2C2 and GdB2C2 on the Basis of Single-Crystal X-Ray Data
Authors: Reckeweg Olaf , DiSalvo Francis J.
Published: March 2014

Samples of YB2C2 and GdB2C2 were synthesized by arc-melting and subsequent annealing of the products. Single crystals of the title compounds were examined with single-crystal X-ray methods. Five different tetragonal unit cell settings from the literature (obtained on the basis of symmetry considerations) were used for the refinement of the crystal structure of YB2C2, but a converging refinement was only achieved for the structural model in the space group P4=mbm (no. 127, Z = 2) with a = 533:27(3) and c = 354:58(3) pm, without obvious inconsistencies. Nevertheless, the results for the five different unit cell settings are compared and discussed. A refinement of the crystal structure of the isotypic compound GdB2C2 was also performed with the lattice parameters a = 537:46(6) and c = 364:98(11) pm. Neither EuB2C2 nor YbB2C2 were obtained by melting coldpressed pellets with the nominal composition RE1.5B2C2 in an arc-furnace or an induction furnace, or by just heating the pellets in sealed Ta ampoules
Residential water meter selection using the analytical hierarchy process
Authors: Mutikanga Harrison E.
Published: March 2014

The need for accurate measurement of water used by customers has led to technological advances in diverse types of water meter designs. However, the question of which meter is the best continues to trouble water utility managers. Until now, there have been no set guidelines for water meter selection. The traditional approach for selecting a water meter has been based on initial meter error performance and price. Although this information is useful, it is inadequate for optimal meter selection because water meter performance is influenced by multiple factors in real‐world operating conditions. This article proposes a methodological framework for residential water meter selection using an analytical hierarchy process and performance/ economic criteria. The application of the proposed procedure is illustrated using the Kampala water utility in Uganda as an example. The best meter for the water utility was the multijet meter type.
Can a snow structure model estimate snow characteristics relevant to reindeer husbandry?
Authors: Rasmus Sirpa , Kumpula Jouko , Siitari Jukka
Published: March 2014

Snow affects foraging conditions of reindeer e.g. by increasing the energy expenditures for moving and digging work or, in contrast, by making access of arboreal lichen easier. Still the studies concentrating on the role of the snow pack structure on reindeer population dynamics and reindeer management are few. We aim to find out which of the snow characteristics are relevant for reindeer in the northern boreal zone according to the experiences of reindeer herders and is this relevance seen also in reproduction rate of reindeer in this area. We also aim to validate the ability of the snow model SNOWPACK to reliably estimate the relevant snow structure characteristics. We combined meteorological observations, snow structure simulations by the model SNOWPACK and annual reports by reindeer herders during winters 1972-2010 in the Muonio reindeer herding district, northern Finland. Deep snow cover and late snow melt were the most common unfavorable conditions reported. Problematic conditions related to snow structure were icy snow and ground ice or unfrozen ground below the snow, leading to mold growth on ground vegetation. Calf production percentage was negatively correlated to the measured annual snow depth and length of the snow cover time and to the simulated snow density. Winters with icy snow could be distinguished in three out of four reported cases by SNOWPACK simulations and we could detect reliably winters with conditions favorable for mold growth. Both snow amount and also quality affects the reindeer herding and reindeer reproduction rate in northern Finland. Model SNOWPACK can relatively reliably estimate the relevant structural properties of snow. Use of snow structure models could give valuable information about grazing conditions, especially when estimating the possible effects of warming winters on reindeer populations and reindeer husbandry. Similar effects will be experienced also by other arctic and boreal species.
Electromagnetic wave absorption characteristics of multiwalled carbon nanocoils
Authors: Eguchi Usaburo , Takikawa Hirofumi , Suda Yoshiyuki
Published: March 2014

We have studied the electromagnetic wave absorption properties of a multiwalled carbon nanocoil (MWCNC), a promising lightweight and wide-band electromagnetic wave absorber. Experiments were conducted using several types of paste with various weight concentrations of MWCNC compounded into an organic binder. The results revealed the significant electromagnetic wave absorption potential of the MWCNC. They also verified that its electromagnetic wave absorption effect is strongly dependent on MWCNC concentration, so that there is an optimal MWCNC composition. The increased sample thickness enhances electric conduction loss and encourages electromagnetic wave absorption, even in a high-frequency range. Consequently, the MWCNC has been demonstrated as a new outstanding electromagnetic wave absorber.
Precision Reactive Sputter Etching and Its Applications
Authors: Lechaton J. S. , Srinivasan G. R. , Gaur S. P.
Published: March 2014

A precision reactive sputter etching process was developed for accurately etching single crystal silicon. This allows one to modify existing device structures and to create new devices in a repeatable way. The process relies on the in situ monitoring of an optical interference signal from a polysilicon film deposited over an SiO2 layer. By this method the etch depth can be controlled to within ±10 nm. This technique has been used to study the device characteristics of thin base and thin emitter transistors without any noticeable device degradation arising from ion impact damage. This is achieved by using Cl2/Ar gas. Two wafers etched at a time in four runs showed a standard deviation of less than 14% in current gain. For the thin emitter study, the current gain decreased significantly for emitters thinned below 200 nm because of enhanced hole diffusion. We believe that this technique will become increasingly important in the future for studying the device characteristics and for making new device structures.
High Voltage Electron Beam Writing for Submicron Design Rule VLSI Fabrications
Authors: Yoshimi Makoto , Takahashi Minoru , Kawabuchi Katsuhiro , Kato Yoshihide , Takigawa Tadahiro
Published: March 2014

The advantages of high voltage electron beam lithography in submicron VLSI fabrications have been established. By electron beam lithography with 50 kV acceleration voltage, vertically walled PMMA pattern is obtained at a relatively low dose, 50 µC/cm2. This fact, combined with the increase in beam current, brings about the improvement of throughput in 50 kV writing by a factor of 5 over 20 kV writing. Proximity effect is markedly reduced in 50 kV writing. The pattern size variation due to the proximity effect is within 0.05 µm for line patterns ranging from 10 µm to 0.25 µm. Vertically walled PMMA pattern of 0.25 µm space, which is equal in size
to the beam spot, is obtained at 50 µC/cm2 in 50 kV writing. In addition, it is shown that radiation damage of MOSFET's due to the 50 keV beam is essentially the same as that due to 20 keV beam.
(Invited) Laser Annealing of Semiconductors
Authors: White C. W.
Published: March 2014

Transient processing using directed energy sources provides unique capabilities for the processing of semiconductors. This article reviews the status of transient processing with the emphasis on laser annealing. Areas are identified where the unique capabilities of transient processing can be utilized.
Radiation Damage in MOS Devices Underlying an Electron Beam Annealed SOI Structure
Authors: Saitoh Shuichi , Higuchi Kohei , Okabayashi Hidekazu
Published: March 2014

Radiation damage due to electron beam annealing has been investigated in MOS devices underlying an electron beam annealed Silicon-on-Insulator structure. A high degree of residual damage (surface state and positive charge) is found to exist in MOS devices. The damage can be easily annealed out by low temperature (500–550°C) furnace annealing, when underlying MOS devices exist outside the electron beam range. However, high temperature furnace annealing at about 1000°C is necessary to eliminate the damage, when the electron beam penetrate through the gate oxides in MOS devices. Use of a low energy electron beam is recommended, based on these results, for the Silicon-on-Insulator formation for three-dimensional ICs.
Threshold Condition and Design of Surface Emitting GaInAsP/InP Injection Lasers
Authors: Soda Haruhisa , Motegi Yoshihiro , Iga Kenichi
Published: March 2014

The threshold condition of a GaInAsP/InP surface emitting laser (λg=1.3 µm) has been discussed. It has made clear that the short cavity structure made of only epitaxial layers, the thicker active layer and high reflectivity mirror could improve the laser characteristics. By taking these points into consideration we have fabricated a surface-emitting GaInAsP/InP injection laser with short cavity length (∼10 µm) which operates at 1.22 µm of wavelength with threshold current of 160 mA (33 kA/cm2) at 77 K. The discussion was made also on the threshold current density by comparing the experimental and theoretical result.
Monolithic Hot Electron Transistors in Silicon with FT>1 GHz
Authors: Shannon J. M. , Slatter J. A. G.
Published: March 2014

Monolithic Hot Electron Transistors have been made in silicon using dopant implantation at low energies. A reverse biassed metal-semiconductor barrier was used as an emitter and a camel diode as a collector. A maximum available gain of >20 dbs was measured at low frequencies but the performance of these transistors was degraded by a large base contact series resistance. The F
T increased with emitter current up to a value of 3 GHz and was determined solely by the charging time of the tunnel emitter.
A New Short Channel MOSFET with an Atomic-Layer-Doped Impurity-Profile (ALD-MOSFET)
Authors: Yamaguchi Ken , Shiraki Yasuhiro , Katayama Yoshifumi , Murayama Yoshimasa
Published: March 2014

A new device structure with an atomic-layer-doped (ALD) impurity profile is proposed to decrease device size and to achieve high speed operation. Device performance is evaluated by computer simulation, and it is clarified that the potential and current flow distributions in MOSFETs with the ALD profile are effectively modulated. Punch-through in ALD MOSFETs is completely suppressed even for L
eff=0.2 µm. The minimum channel length, L
min, restricted by V
TH lowering is extended into the submicron range, while the L
min of conventional structure MOSFETs remains near 1 µm. Furthermore, it is shown that the process margin is sufficient to fabricate ALD MOSFETs by molecular beam epitaxy technology. Thus, it is concluded that the ALD structure is attractive and promising for developing devices with short channels.
Heterojunction Effect on Spectral and Frequency Responses in InP/InGaAsP/InGaAs APD
Authors: Yasuda Kazuhito , Shirai Tatsunori , Kishi Yutaka , Yamazaki Susumu , Kaneda Takao
Published: March 2014

Influence of the valence band discontinuity on the spectral and frequency responses in InP/InGaAsP/InGaAs APDs has been reported. Quantum efficiency showed gradual increases in the wavelength range from 1.0 to 1.3 µm, where the absorption coefficients decrease with increasing wavelength. Frequency response deteriorations, which cannot be explained by usual deterioration mechanisms, were found at around 300 MHz. These two characteristics are due to holes piled up at the heterointerface which was confirmed experimentally. Recombination and thermionic emission of piled up holes cause the deterioration of quantum efficiency and frequency response, respectively. High speed APDs are realized by increasing the electric field of the heterointerface in InP/InGaAsP/InGaAs APDs.
(Invited) InGaAsP Visible Laser Crystal
Authors: Watamabe Hisatsune , Usui Akira
Published: March 2014

InGaAsP crystal is proposed as a new visible laser material. Two advantages, i.e. no aluminum and the large tetragonal distortion, are expected to be effective for the realization of higher reliability lasers. With comparing with other epitaxial techniques, the dual-growth-chamber hydride VPE is explained as a successful technique to grow an InGaAsP visible laser structure. InGaAsP visible laser characteristics including the room temperature cw operation and a preliminary aging test are described.
Visible GaAlAs Laser with a Buried-Convex Waveguide Structure
Authors: Shima Katsuhito , Hanamitsu Kiyoshi , Wakao Kiyohide , Takagi Nobuyuki , Tabuchi Haruhiko , Takusagawa Masahito
Published: March 2014

A new buried-heterostructure visible GaAlAs laser, called a buried-convex waveguide structure (BCS) laser, has been developed. BCS lasers exhibit a highly stable transverse and single longitudinal mode operation in the 750 to 870 nm wavelength range. Very low threshold currents of 10–20 mA are obtained for the wavelength at about 750 nm. The output beam of BCS lasers has an aspect ratio of 2.0–2.5 and has no astigmatism. The relative intensity noise of BCS laser is very low at a level below -150 dB/Hz and is constant in the temperature range between 10 and 50°C. The maximum output power ofBCS lasers with facet coating is almost independent of the lasing wavelength between 750 and 870 nm.
(Invited) Surface Acoustic Wave Devices on Silicon
Authors: Gunshor R. L. , Martin S. J. , Pierret R. F.
Published: March 2014

Surface acoustic wave (SAW) devices can be used to perform a number of real-time signal processing functions. Originally, SAW devices were constructed on single-crystal piezoelectric materials such as LiNbO3 and quartz. In this paper we discuss the manner in which several SAW devices can be implemented on non-piezoelectric silicon substrates, thereby facilitating their use in integrated circuits. The pn diode memory correlator and the SAW resonator are discussed in detail. The ZnO/SiO2/Si layered medium can be made temperature stable by controlling the thermal SiO2 thickness. This, together with new ageing data, demonstrates the practicality of including SAW devices in monolithic integrated circuits.
Inter facial Trapping and MIS Device Stability on InP
Authors: Lile Derek , Taylor Marylin , Meiners Larry
Published: March 2014

The time dependent response of MIS-gated enhancement-mode FETs on InP has been studied as a function of temperature for a variety of surface and dielectric preparation conditions including direct versus indirect plasma-enhanced CVD and the use of SiO2 as compared to Al2O3 for the insulator. The results suggest that thermally-activated tunneling is the mechanism responsible for the long term changes of channel current observed in these devices and that its magnitude is critically dependent on the details of device preparation employed.
Design Considerations of Coupling Capacitors in GaAs Integrated Circuits
Authors: Livingstone Alec , Welbourn David
Published: March 2014

Capacitor coupling of GaAs depletion mode FETs is being pursued as a method of achieving low power integrated circuits which are tolerant of widely varying process parameters. The performance of these capacitors has been examined in three particular areas; the effect of backbias applied to an adjacent contact, the effect of geometry on the frequency dependence of the capacitance and alternative capacitor structures. The results have significance beyond capacitor coupling because they reveal the interaction of active device layers with other circuit elements, results which become increasingly important as high packing densities are approached on GaAs wafers.
Electrical Properties of Mo/III-V Compounds Schottky Barriers
Authors: Lin M. S. , Su W. H. , Lou J. C. , Lei T. F.
Published: March 2014

0.1 µm Mo layers are deposited on III-V compounds by electron-beam evaporation. The electrical properties and interface of Schottky barriers are assessed by I-V, C-V, DLTS and Rutherford Backscattering (2 MeV He+, θ=160°). The near-ideal Schottky diodes (n<1.05) are formed and thermionic emission mechanism is applicable in these Mo/III-V systems. In the defect-free Mo/GaAs (epitaxy) system, the reverse current behavior can be expressed by the Andrews and Lepselter model. The deep hole trap with energy of E
v+(0.93±0.04) eV is observed in the Mo/GaAs (undoped) system and attributed to the native defects of bulk GaAs. The thermal stability of Mo/GaAs Schottky barrier is greater than that of Mo/GaAs0.6P0.4, and the Mo/GaAs Schottky barrier can be used in high power IMPATT and MESFET devices.
Characterization of Computer Controlled GaP Single Crystals
Authors: Watanabe Masayuki , Ushizawa Jisaburo , Washizuka Shoichi , Kokubun Yoshihiro
Published: March 2014

GaP single crystals grown by computer-controlled liquid encapsulated Czochralski (C-LEC) method were characterized as compared with commercially available <111> and <100> oriented crystals. The C-LEC crystals grown with temperature gradients lower than 70°C/cm had dislocation densities less than 5×104 cm-2, and the etched surface showed smooth background with only D-pits (B-pit free). All C-LEC crystals included no macroscopic defects such as impurity precipitates and voids which were frequently observed in the commercially available crystals grown using a “coracle”.
Yellow LEDs fabricated using the C-LEC <100> crystal having less than 5×104 cm-2 dislocation density showed high external quantum efficiency of 0.3%, which was the highest ever reported for yellow LEDs. Green emission in GaP: N epitaxial layer using C-LEC <111> crystals showed high efficiency and uniform distribution.
(Invited) Polyacetylene: A Typical Semiconducting and Metallic Polymer
Authors: Shirakawa Hideki
Published: March 2014

This paper presents an introductory review of polyacetylene, a typical semiconducting and metallic organic polymer. The electrical conductivity of polyacetylene can be tailored by appropriate “chemical and/or electrochemical doping” with electron accepting or electon donating reagents, spanning the range of insulators (10-12 S/cm) and metals (103 S/cm). Some of the potential applications of the doped polyacetylene are described.
(Invited) Amorphous Silicon Transistors and Integrated Circuits
Authors: Matsumura Masakiyo
Published: March 2014

Theoretical and experimental studies of amorphous-silicon field-effect-devices developed in Tokyo Institute of Technology are reviewed in this paper. Mobility as high as 1.9 cm2/Vsec, which is about an order of magnitude higher than the one reported to data, was observed. The first amorphous-silicon logic circuits, image sensors and charge coupled devices are presented. Problems which must be overcome, are described.
Fast Switching Array using Liquid Crystal for Electrophotographic Printer
Authors: Sugimura Akihiko , Ueda Yasuhiro , Moriwaki Kohsuke , Yamamoto Nobuyuki , Kawamura Takao
Published: March 2014

A new type of high speed liquid crystal switching array is developed. The device has a simplified electrode configuration which allows a simple high speed operation and a small size cell design. Short response time of 0.5 msec and high ON/OFF light transmission ratio of 80 with 18% of total transmission are obtained for a switching array of 10 dots/mm. By applying this type of array to a character printer with loaded by amorphous silicon drum, a good hard copy is obtained at 1400 lines/min (14 pages/min for A4 size).
A New Method for Measuring Noise Figure of Microwave Transistor
Authors: Yulu Cao
Published: March 2014

This paper introduces a fast and accurate method for measuring noise figure of microwave transistor using a microwave modulating receiver. The result measured by this method indicates only the noise figure of device without the contribution of receiver. The noise figures of Si microwave transistor and GaAs MESFET have been tested. Finally, some possible influences on the accuracy of measurement are discussed.
Redundancy Techniques for Dynamic RAMs
Authors: Shimohigashi Katsuhiro , Ishihara Masamichi , Shimizu Shinji
Published: March 2014

This paper describes redundancy techniques designed for a 256 K dynamic RAM with polysilicon fuses which are used as electrically programmable ROMs. It shows that four spare rows and columns are suitable for obtaining the maximum yield improvement in the RAM. The first level polysilicon is used for the fuse and a two step etching process is employed to remove the PSG and final passivation layers.
Fusing characteristics have been studied and a model based on a thermal equation is presented.
A 256 K dynamic RAM test device with redundancy was designed and fabricated using 2 µm lithography. It was found that the yield could be improved by a factor of 5–10, if four spare rows and columns were incorporated.
Diffusion Length Measurement Using Dynamic MOS RAM
Authors: Kumanoya Masaki , Taniguchi Makoto , Yamada Michihiro , Kobayashi Toshifumi , Nagayama Yasuji , Nakano Takao
Published: March 2014

A new method for the diffusion length measurement has been proposed using the minority carrier injection in the conventional 64 K dynamic RAM. The temperature dependence of the diffusion length has been measured by this method. The experimental results confirmed the validity of this method for the dynamic RAM analysis.
Nonlinear Interaction of Surface Acoustic Waves in Waveguide
Authors: Nakagawa Yasuhiko , Ono Mitsuhiro
Published: March 2014

Theoretical and experimental results are reported for the nonlinear interaction of the surface acoustic waves (SAW) in a (Δv/v) waveguide on YZ · LiNbO3. The generation of the SAW at the sum frequency of the two input SAWs propagating in opposite directions is analyzed. It is shown in this paper that the propagation direction of the SAW at the sum frequency is controllable by changing the wave-vector ratio of the two input SAWs. The efficiency of generation strongly depends on the (Δv/v) velocity ratio and the width of the waveguide.
Investigation of a SAW Resonator for a Voltage Controlled Oscillator
Authors: Kojima Toshihiro , Obara Hiroyuki , Shibayama Kimio
Published: March 2014

Two kinds of SAW resonators using IDT reflectors on the substrate of LiNbO3 are described. One is a tunable resonator and the other is a compact resonator. Utilizing these resonators, two kinds of voltage controlled oscillators were developed and exhibited 0.14∼0.25 percent tuning ranges.
High Frequency Operation for Resin-Coated BAW Beam Devices
Authors: Yamaguchi Masatsune , Hashimoto Ken-ya , Uzawa Koichi , Kogo Hiroshi
Published: March 2014

The paper deals with an effective high frequency operation for resin-coated bulk acoustic wave (BAW) beam devices. Theoretical analysis for 41°-rotated Y-cut LiNbO3 showed that by using mode conversion on reflection from fast shear to longitudinal wave beams or vice versa, centre frequencies of the device can be increased by up to about 2.3 times compared with SSBW devices. Experimental results were in good agreement with the theoretical prediction.
Fabrication Techniques and Properties of Piezoelectric Thin Films of ZnO and AlN
Authors: Kawabata Akira
Published: March 2014

Piezoelectric films of ZnO and AlN have been fabricated by sputtering. The film is assessed to be of good quality by means of X-ray diffraction, scanning electron microscopy, resistivity and electromechanical measurements. The ZnO/glass and ZnO/crystal composites have been used as SAW devices. A c-axis oriented AlN film has been grown on a glass or metal film substrate at substrate temperature as low as 20∼500°C. An epitaxial ZnO and A1N film has been grown onto a basal plane sapphire substrate. A SAW propagated along c-axis of the ZnO films on the (011̄2) planes of sapphire will be available as a high frequency filter device above 1 GHz.
Laser-Acoustic Microscope
Authors: Itoh Masahide , Yatagai Toyohiko , Hino Makoto , Takahashi Ichirou , Saito Hiroyoshi , Kim Pil Hyon , Namba Susumu
Published: March 2014

We have developed a laser-acoustic microscope system to obtain non-destructively the subsurface structures of optically opaque samples. The modulated laser beam focused on the sample generates a photoacoustic signal which is detected by a microphone. Two-dimensional scanning provides for the subsurface images of optically opaque samples. The surface absorption of the samples, to which the photoacoustic signal is proportional, are cancelled by measuring their reflectivity. A unique feature of this technique is that the image contrast comes from spatial variation in the sample thermal properties. The optical spot size of about 1 µm is obtained for the photoacoustic imaging.
Load Test of Bolt-Clamped Langevin Type Vibrator
Authors: Mori Eiji , Ueha Sadayuki , Tsuda Yoneo , Kaneko Seiji , Okada Kozo , Masuda Michiyuki , Ohoya Kanji
Published: March 2014

The temperature rise of several kinds of bolt-clamped Langevin type vibrators which are used in the design of high power ultrasonic vibration equipment is measured as a function of operating time. Employing the wattmeter method and the variable mechanical load resistance proposed by the authors, the measurements are carried out for various values of the parameters of mechanical output power, mechanical load resistance and vibration velocity. The electroacoustic efficiencies of the vibrators are also measured using the same method.
Universality in Critical Anomaly of Acoustic Properties of Binary Mixtures
Authors: Tanaka Hajime , Nishi Toshio , Wada Yasaku
Published: March 2014

The universality of acoustic anomaly near the consolute point is verified for three binary mixtures, aniline/cyclohexane, nitrobenzene/n-hexane and nitrobenzene/n-heptane. Relative dispersion δ=[u–u(0)]/u(0) (u is the ultrasonic velocity and u(0) the zero-frequency sound velocity) and critical absorption per wavelength αλ were obtained from precise measurements of ultrasonic velocity, absorption and low frequency adiabatic compressibility. The ratios δ/αλ, δ/A and αλ/2πA (A is the critical amplitude) plotted against the reduced frequency ω* coincide respectively among the three mixtures in the range of ω* from 10-1 to 5×104.
Ultrasonic Elastic Constants of Muscle
Authors: Hatta Ichiro , Hasegawa Masahiko , Nakayama Hideo , Tamura Youjirou
Published: March 2014

All of the elastic stiffness components of striated muscle are composed c
11, c
33, c
12, c
13 and c
44. In the resting state, c
11 and c
33 are found to be 2.25×109 N m-2 and 2.41×109 N m-2, respectively. In the active tetanus state, c
11 and c
33 become 2.18×109 N m-2 and 2.47×109 N m-2, respectively. On the other hand, c
44 is negligible in comparison with c
11 and c
33, and c
12 is nearly equal to c
11 in the resting state. From a consideration of elastic energy, it is revealed that muscle lies near an unstable state elastically.
A Pulsed Ultrasonic Radar Vehicle Detector Realization
Authors: Futsuhara Koichi
Published: March 2014

This paper describes the construction of a highly reliable pulsed ultrasonic radar vehicle detector used in the measurement of roadway vehicular traffic. The system of this detector is constructed with three types of ultrasonic transducers and a single ultrasonic transceiver and has the following characteristics: 1) the standard detection zones where vehicle detection is desired reappear when transducers are exchanged without tuning of the transceiver, because particular interfaces are built into the transducers, and 2) vehicle detections are accurate because the gated receiver has the function of a follow-up control on a time base for atmospheric temperature variations and the detector's outputs are synchronized with the transmitting pulses.
Pseudo Surface Acoustic Wave Resonator for UHF Range VCO
Authors: Sato Hiroaki , Morishita Shigefumi
Published: March 2014

A design procedure of a piezoelectric resonator for a wide tunable voltage-controlled Colpitts-type oscillator and the successful realization of a low noise oscillator using a 36° Y-X LiTaO3 pseudo surface wave resonator with capacitance ratio γ≃32 are described. The realized performances of C/N≧82 dB and S/N≧51 dB in the tunable range of Δ
f/f
0≃0.43% are adequate for the local oscillator in a mobile radio communication unit with channel separation of 25 kHz.
SAW Properties of PLZT Epitaxial Thin Films
Authors: Adachi Hideaki , Mitsuyu Tsuneo , Wasa Kiyotaka
Published: March 2014

Thin films of PLZT with (111) orientation were epitaxially grown on c-plane of sapphire by rf-magnetron sputtering. The poling treatment was carried out under an applied field along <1̄1̄2> direction of PLZT and SAW was excited along the same direction by an interdigital transducer. The coupling constant k
2 was about 0.85% for the fundamental mode of SAW at normalized thickness K
d=0.42. The result indicates that the piezoelectric effect of the present PLZT thin film is as strong as BaTiO3.
A Phase Shift Keying Communication System Using SAW Devices
Authors: Toda Kohji , Ohkubo Hiroshi
Published: March 2014

A method is described for constructing a phase shift keying (PSK) system using surface acoustic wave (SAW) devices. The SAW device having three interdigital transducers, two for input and one for output, operates as the key element in the communication system. In the transmitting system, the device is used to generate a phase shift keyed rf signal corresponding to an input binary impulse train. The device is also requisite for synchronization and demodulation in the receiving system. A total communication system is demonstrated practically.
Studies on Ultrasonic Plastic Welding with Two Longitudinal Vibration Systems
Authors: Tsujino Jiromaru
Published: March 2014

Ultrasonic plastic welding with two longitudinal vibration systems is proposed and studied. The welding limit of this system is double that of a conventional ultrasonic welding method with one vibration system. In transmission welding, the vibration distribution along a welding specimen can be changed by controlling the vibration phase difference between upper and lower welding tips. The welding position can be set at a vibration stress maximum position by controlling the vibration phase difference. This method with two vibration systems has various useful features and is effective in plastic welding.
Ultrasonic Fractography Studies on Discontinuous Fracture Propagation in Polymers
Authors: Takahashi Kiyoshi , Mada Toshio
Published: March 2014

Ultrasonic fractography studies were performed on glassy polymers, PMMA and epoxy. Transient fracture velocity change during highly discontinuous propagation in DCB type PMMA specimens has been measured precisely. It has been shown that fracture abruptly slows down with a speed on the order of 100 m/s. Measurements in pre-cracked epoxy resins, araldite-B and -D, revealed that the former had two kinds of initial fast fracture velocities just after the onset of instability, while the latter exhibited behavior similar to pre-cracked PMMA tensile specimens.
Frequency Modulator using Ultrasonic Vibrator
Authors: Kato Terumasa , Georgiev Zdravko , Hatta Ichiro
Published: March 2014

An ultrasonic bulk wave delay line oscillator is presented composed of a piezoelectric vibrator and an amplifier. The field effect of the oscillation frequency is explained in terms of the ultrasonic wave velocity change by higher order elastic effect which is generated with inner stress by piezoelectric effect.
A stress coefficient K and a field coefficient K
e
31 resulting from the higher order elastic effect are obtained as K=1030×10-6 MPa-1 and K
e
31=1.77×10-3 cm/KV, respectively.
Characteristics of the Piano-Convex Ultrasonic Transducer
Authors: Kobayashi Tsutomu
Published: March 2014

The plano-convex transducer has the superior features of broad frequency bandwidth, transmission and reception of a very short ultrasonic pulse and radiation of focused ultrasonic waves. Those features can improve the resolution in ultrasonic imaging and non-destructive testing.
In order to design and use these sorts of transducers, more detailed characteristics are necessary. The following characteristics are investigated in this paper: radiation patterns for continuous and pulse waves in water, vibration modes, ringing for an applied impulse voltage and its suppression, and radiation patterns of impulse waves in steel and focal distance.
Mass Screening of Breast Cancer by Ultrasound Transmission Technique–Theoretical Considerations
Authors: Hayakawa Yoshinori , Inada Tetsuo , Ueno Ei , Aiyoshi Yuji , Aoshima Nobuharu , Yosioka Katuya , Wagai Toshio
Published: March 2014

A method of mass screening for breast cancer by ultrasound transmission technique is proposed. The method uses pulsed ultrasound waves that pass through the pressed breast. Distribution of mean velocity of transmission subtracted by a constant, e.g., velocity of ultrasound in water, should be displayed in an image. The feasibility of the method is theoretically discussed with the affirmative results. In this discussion, the thickness of the pressed breast is assumed to be 5×10-2 m, that of a malignant tumour to be 5×10-3 m. The velocity of ultrasound in normal tissue is assumed to be 1430 m/s, that in a tumour to be 1471 m/s.