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As variáveis qualitativas possuem características de influenciar variáveis quantitativas. As séries temporais são exemplo de variáveis quantitativas que podem ser modificadas por alterações abruptas de variáveis qualitativas. O objetivo desta pesquisa é identificar uma lacuna de conhecimento entre modelos de previsão de séries temporais e variáveis qualitativas por meio deuma revisão sistemática de literatura aplicada em artigos científicos publicados em bases internacionais. Foram encontrados 37 artigos que unem séries temporais e variáveis qualitativas no período de 1985 a 2020, nos quais novos modelos foram criados utilizaram as variáveis qualitativas como entradas de informação para a geração de previsões. A lacuna encontrada foi em aproximados 57% dos casos a capacidade de melhoria dos modelos criados e a aplicação em outros sistemas, e em 19% a possibilidade de melhorar a previsão de outras variáveis do sistema. Os resultados indicaram que a inclusão de variáveis qualitativas em modelos quantitativos auxilia na qualidade da precisão das previsões geradas.

This study aimed to price croplands in Rio Grande do Sul State (southern Brazil) and point which variables had the most significant impact on prices. The main purpose was achieved using multiple linear regression and principal component analysis. The variables used in this study were planted area, production, price, and yield of the commodities soybean, wheat, and corn. The period under analysis was from January 1994 to December 2017 (biannual observations). Multiple linear regression showed that five variables contributed to land pricing, being three related to soybean and two to wheat. Multivariate analysis grouped the investigated variables into clusters and indicated their influence, in addition to providing information on land prices and reducing variable dimensionality from fourteen original variables to three principal components to be analyzed. The two analyses complemented each other so that the croplands’ price was explained by three variables, in which two corroborated in constructing the pricing model for croplands. RESUMO: Este estudo teve como objetivo a precificação de terra para lavouras no Rio Grande do Sul e apresentar quais variáveis possuem maior impacto no preço. O objetivo foi alcançado por meio da aplicação da análise de regressão linear múltipla e de componentes principais. Variáveis relacionadas às commodities soja, trigo e milho, como a área plantada, produção, cotação e rendimento, formaram o banco amostral para as duas metodologias, compreendendo o período de janeiro de 1994 a dezembro de 2017, em observações bianuais. A regressão linear múltipla mostrou que três variáveis relacionadas à soja e duas ao trigo contribuem na precificação das terras. A análise multivariada agrupou as variáveis investigadas, indicando a influência entre as mesmas, fornecendo informações sobre o preço de terras e diminuindo a dimensionalidade do problema de 14 variáveis originais para três componentes a serem analisados. As duas análises se complementaram de forma que o preço de terras foi explicado por três variáveis e duas corroboraram na construção do modelo de precificação das lavouras.

O Sistema Toyota de Producao (STP) e uma metodologia para formular acoes gerenciais de melhoria em sistemas de producao. Dentro desse sistema, uma etapa e a eliminacao de perdas nos processos produtivos, tecnica conhecida como a identificacao das sete perdas. Em sistemas produtivos simples, como empresas produtoras de mel, apiarios, normalmente nao sao elaboradas tecnicas de melhoramento, devido principalmente ao pequeno tamanho dessas empresas e serem apenas atividades de complemento de renda a pequenos agricultores. Porem, a producao de mel representa uma das atividades que fornece grandes oportunidades para a agricultura familiar. Com isso, o objetivo desse estudo de caso e identificar as perdas por meio do Sistema Toyota de Producao em um apiario e realizar as proposicoes de melhorias. A justificativa do estudo consiste em melhorar o sistema produtivo de um apiario para aumentar a lucratividade dessa empresa e servir de exemplo para outras empresas produtoras de mel, a utilizar o STP para melhorar seu sistema produtivo. As perdas identificadas sao principalmente relacionadas ao transporte, movimentacao, estoque e espera, uma das sugestoes e minimizar a distância entre as colmeias e o entreposto, as outras sugestoes estao dispostas mais detalhadas no estudo. Palavras-chave: Sistema Toyota de Producao. Identificacao de Perdas. Apiario. Apicultura. ABSTRACT The Toyota Production System (STP) is a standard for managerial actions to improve production systems. Close up system, one face for the exhaustion processes in product processes, technological software with the identification of seven loss. In simple production systems, honey-producing companies, their own, usually do not elaborate breeding techniques, have their origins, and are just supplementary income activities. However, honey production represents one of the activities that provides the greatest opportunities for family farming. With this, the study of the theme is used as loss through the Toyota Production system in an apiary and perform as propositions for improvements. The justification for the method is to improve the productive system of a program to increase the profitability of a company and to serve as an example for other energy producing companies, such as STP for its production system. The losses are related to the transport, the movement, the stock and the wait, the output of videos is minimal between the colias and the warehouse. Keywords: Toyota Production System. Losses Identification. Apiary. Beekeeping.

O presente trabalho aborda um estudo de caso sobre os fatores que influenciam o retorno indevido de biscoitos dos varejistas do sul do Estado de Minas Gerais, realizado em uma indústria de médio porte produtora deste item. As justificativas são expostas para a realização do estudo, fundamentação teórica acerca da logística reversa, canais de distribuição, gestão de vendas e estoques, bem como roteirização. Para a aplicação do estudo, utilizaram-se questionários e entrevistas com o gestor da empresa, os quais visavam entender como o processo de gestão de vendas afetava o retorno de biscoitos e a lucratividade da empresa.

Purpose – This paper aims to present a Systematic Literature Review (SLR) of studies in Brazil with applications of multivariate control charts indexed in journals on the Web of Science. Design/methodology/approach – The following steps were carried out: a detailed synthesis was performed on the general characteristics of the corpus, co-citation and collaboration networks analyzed; and a co-occurrence of terms in the text corpus was verified. A Systematic Literature Review was carried out using the protocols set out by Biolchini et al. (2007), Kitchenham (2004) and Tranfield, Denyer and Smart (2003). Papers were selected from the Web of Science database, and after applying filters, results for 29 articles were given to compose the corpus. Findings – A tendency was found for an increase in publications, along with more international research on the issue. The journal most used for publication was the Microchemical Journal. This analysis provided relevant authors for research in this area: Harold Hotelling, Douglas Montgomery, and John Frederick MacGregor. Important Brazilian researchers were highlighted who work mainly in the pharmaceutical and biodiesel industry. Originality/value – No articles were found that had carried out a Systematic Literature Review of Brazilian research on multivariate control charts. The main contributions to this manuscript related to an increase in scientific know-how in the area of multivariate and bibliometric analysis. Keywords - Multivariate Control Charts. Systematic literature review. Bibliometric analysis.

The impact of air pollution on humans is a worrisome factor that has gained prominence over the years due to the importance of the topic to society. Lung cancer and chronic obstructive pulmonary disease are among the diseases associated with pollution that increase the mortality rate in Brazil and worldwide. Therefore, this study aimed to determine the impacts of air pollutants on mortality rates from chronic obstructive pulmonary disease (COPD) and lung cancer (LC) using vector autoregressive (VAR) modeling. The adjusted model was a VAR(1) and, according to the Granger causality test, the air pollutants selected were PM10, O3, CO, NO2, and SO2. The shocks applied to the variables O3, using the impulse response function, negatively impacted COPD; in the eighth period, which is stabilized. The LC variable suffered more significant variations from O3 and after a shock in this variable, an initially negative response in LC occurred and the series stabilized in period nine. After one year, 20.19% of COPD variance was explained by O3. After twelve months, the atmospheric pollutant O3 represented 5.00% and NO2 represented 4.02% of LC variance. Moreover, the variables that caused the highest impact on COPD and LC mortality rates were O3 and NO2, indicating that air pollution influences the clinical state of people who have these diseases and even contributes to their development. The VAR model was able to identify the air pollutants that have the most significant impact on the diseases analyzed and explained the interrelationship between them.

The bee Apis mellifera plays an important role in the balance of the ecosystem. New technologies are used for the evaluation of hives, and to determine the quality of the honey and the productivity of the hive. Climatic factors, management, flowering, and other factors affect the weight of a hive. The objective of this research was to explain the interrelationship between climatic variables and the weight of an Apis mellifera beehive using a vector autoregressive (VAR) model. The adjustment of a VAR model was carried out with seven climatic variables, and hive weight and its lags, by adjusting an equation that represents the studied hive considering all interrelationships. It was proven that the VAR (1) model can effectively capture the interrelationship among variables. The impulse response function and the variance decomposition show that the variable that most influences the hive weight, during the initial period, is the minimum dew point, which represents 5.33% of the variance. Among the variables analyzed, the one that most impacted the hive weight, after 20 days, was the maximum temperature, representing 7.50% of the variance. This study proves that it is possible to apply econometric statistical models to bee data and to relate them to climatic data, contributing significantly to the area of applied and bee statistics.

O desemprego tem sido fator de grande preocupacao para toda a populacao do Brasil e do mundo. Desde a crise internacional economica de 2008, diversos paises tem sofrido com seu avanco, e seus efeitos sao sentidos em todos os nucleos da sociedade, familiar, empresarial e governamental. Este estudo tem por objetivo investigar a taxa mensal de desemprego no Brasil, por meio de modelos da classe geral ARIMA. O banco de dados coletado para o estudo refere-se a serie de desemprego nas regioes metropolitanas do Brasil: Recife, Salvador, Belo Horizonte, Rio de Janeiro, Sao Paulo e Porto Alegre, em percentuais e com coleta mensal, correspondendo ao periodo de marco de 2002 a junho de 2016, com 172 observacoes. A metodologia empregada e da modelagem ARIMA. O modelo ajustado possibilitou a realizacao de previsoes in sample . O processo gerador da serie e um auto regressivo de ordem 12, necessitando de uma diferenca para tornar a serie estacionaria, apresentando ainda sazonalidade de lag 12 e o modelo selecionado para representar a serie foi o SARIMA (1,1,0) 16(1,0,0)12"> . Palavras-Chaves: Taxa de Desemprego. Regioes Metropolitanas do Brasil. Modelagem ARIMA. Previsoes. Modelagem SARIMA. ABSTRACT Unemployment has been reason of great concern for the Brazilian people and the world's population. Since the economic international crisis of 2008, several countries have suffered from its advance and their effects are felt in all society’s nuclei: family, business and government. This study aims to investigate the monthly unemployment rate in Brazil, through models of general class ARIMA. The database collected refers to the number of unemployment in the metropolitan regions of Brazil: Recife, Salvador, Belo Horizonte, Rio de Janeiro, Sao Paulo and Porto Alegre, in percentage and monthly collection, from March 2002 to June 2016, with 172 observations. The methodology used is the ARIMA modeling. The adjusted model enabled the realization of forecasts in sample. The generating process of the series is an autoregressive of order 12, requiring a difference to make the series stationary and with seasonality in lag 12 and and the model selected to represent the series was SARIMA (1,1,0) 16(1,0,0)12"> . Key words: Unemployment Rate. Metropolitans Regions of Brazil. ARIMA Model. Forecast. SARIMA Model.

Sugar production and exportation are important factors for the Brazilian economy, because Brazil produces the largest amount of sugar and accounts for almost half of the world´s sugar exports. This research aimed to monitor the sugar export from January 2000 to April 2019, by means of residual control charts with pretreatment of autoregressive integrated moving average (ARIMA) models. The data used in the study were collected from the Portal Única website. We opted for the application of ARIMA modeling because the data was not stationarity and presented autocorrelated values. The best model to predict the Brazilian sugar exports was SARIMA (1,1,1)(1,0,1)6 due to the seasonal behavior of the series, which may be related to the sugarcane planting and harvesting period. It was possible to observe the presence of upper-limit outliers in the residual control chart, in October 2012 and February 2016, which characterize a sugar exports higher than forecasted exports.

Brazilian industries in the electro-electronic sector impact other areas of the economy, as they contribute to the generation of employment and income. The objective of this research is to analyze the short-term dynamic behavior vector autoregressive (VAR) models of admission and dismissal, using cluster analysis as a pretreatment to classify variable endogeneity and observe the macroeconomic variables that most impact unemployment. Cluster analysis will be used to determine if the macroeconomic variables related to the Brazilian electro-electronic sector can be classified and selected based on their exogeneity. The VAR model will be used to show the contemporary relationship among the variables and, through the use of the impulse response function and the variance decomposition, help explain their dynamics. The shock imputed by the macroeconomic variables causes employment rate instability that takes two months to return to normal. There is a significant relationship (p ≤ 0.01) between the macroeconomic variables and the number of people admitted and dismissed in the sector, indicating that abrupt changes in the macroeconomic variables will result in fluctuations in the number of employees in the Brazilian electro-electronic industry. The cluster analysis was able to classify the variables as endogenous or exogenous variables, but it was not able to order them based on exogeneity.

A crescente competitividade dos mercados em que as organizações atuam, tem exigido que elas utilizem cada vez mais métodos acurados de previsão para auxiliar nos processos decisórios. O objetivo do presente trabalho foi analisar o desempenho de técnicas individuais e de combinação de previsões no processo de previsão de demanda da ração de peixe de uma agroindústria de pequeno porte. Desta forma, utilizou-se os modelos de Box-Jenkins e de Holt-Winters, assim como a combinação de ambos, visando ajustar um modelo com maior acurácia. A combinação das previsões se deu pelos métodos de média aritmética, de regressão e da variância mínima com erros das previsões individuais não correlacionados, resultando em 5 modelos de previsões. Com os resultados obtidos, constatou-se que o modelo de combinação por regressão foi o que apresentou o melhor desempenho, devendo ser utilizado pelos gestores da empresa na obtenção da previsão da demanda futura.

Novel polyethyleneglycol dialkylglycerol surfactants, 3-methyl-penta ethyleneglycol-2-octyl-1-pentylglycerol (CH 3 (OCH 2 CH 2 ) 5 OCH 2 CHO((CH 2 ) 7 CH 3 )CH 2 O(CH 2 ) 4 CH 3 ), 3-methylpentaethyleneglycol-2-pentyl-1-octylglycerol (CH 3 (OCH 2 CH 2 ) 5 O CH 2 CHO((CH 2 ) 4 CH 3 )CH 2 O(CH 2 ) 7 CH 3 ), 3-methylpentaethyleneglycol-2-(2-ethylhexyl)-1-octhylglycerol (CH 3 (OCH 2 CH 2 ) 5 OCH 2 CHO(CH 2 CH(C 2 H 5 )(CH 2 ) 3 CH 3 )CH 2 O(CH 2 ) 7 CH 3 ), 3-methylpentaethyleneglycol-2-(2-ethylhexyl)-1-(2-ethylhexyl)glycerol (CH 3 (OCH 2 CH 2 ) 5 CH 2 CHO(CH 2 CH(C 2 H 5 )(CH 2 ) 3 CH 3 )CH 2 OCH 2 CH(C 2 H 5 )(CH 2 ) 3 CH 3 ), were synthesized to evaluate the solubility and the possibility for the formation of stable microemulsions in supercritical CO 2 . The surfactants synthesized in this study were satisfactorily dissolved in supercritical CO 2 . However, the quantity of water, which can dissolve into the same system, was very little. It has also become obvious that small water droplets in CO 2 microemulsions stabilized by synthesized surfactants have an ability to incorporate hydrophiles, water-soluble dyes, at the same system.

Simultaneous dyeing and enzyme processing of wool fabrics in a non-ionic surfactant reverse micellar system has been investigated using Polyoxyethylene Sorbitan Trioleate (Tween-85) as a surfactant. Solubilization of enzymes in the Tween-85 reverse micellar system was evaluated by small angle X-ray scattering method. Small angle X-ray scattering analyses showed that the Tween-85 reverse micellar system had an ability to incorporate enzymes and dyes in the interior of reverse micelles without changing their structure. The acid dye and the reactive dye solubilized in the Tween-85 reverse micellar system were effectively adsorbed on wool fabrics. Activities of enzymes in the same system were different depending on the used enzyme and took negative effects from dyes in the system.

Speeds of sound in the liquid phase of 1,1-difluoroethane, CHF2CH3, were measured by a sing-around technique operated at a frequency of 2 MHz. The results cover the temperature range along six isotherms from (243 to 333) K and pressures from near the saturation line to about 30 MPa. The combined uncertainty is estimated to be within ±0.2% except for the region near the coexistence line in the upper temperature range. The vapor pressure was also measured with an uncertainty lower than ±20 kPa by detecting the phase change using an acoustic absorption technique. The speeds of sound in the saturated liquid were estimated by the extrapolation to the vapor pressure from those in the compressed liquid. The temperature and/or pressure effects on the speed of sound are discussed and compared with data for some other hydrofluorocarbons reported elsewhere.

Speeds of sound in liquid tetrachloromethane and benzene were measured at temperatures from 283.15 K to 333.15 K and pressures up to about 30 MPa. The method used was a sing-around technique employing a fixed path acoustic interferometer operated at a frequency of 2 MHz. The probable uncertainty of the present results is less than ±0.2 percent taking into account the errors of ±20 mK for the temperature, and ±(3 to 5) kPa for the pressure measurements. Measured values are fitted to a polynomial equation as functions of temperature and pressure, and the reliability of the present results is discussed in the light of a comparison with reference data reported in the literature.

Dyeing of wool fabrics with conventional acid dyes in a supercritical CO 2 has been investigated using a reverse micellar system. A reverse micelle composed of perfluoro 2,5,8,11-tetramethyl-3,6,9,12-tetraoxapentadecanoic acid ammonium salt/CO 2 /water had a high potential to solubilize conventional acid dyes and to dye wool fabrics in this system. It has found that dyeability of the acid dye on wool in this system take no influence of the density of CO 2 . On the other hand, variation of dyeing temperature resulted in the remarkable differences of the dyeability of the acid dye on wool even though the solubility of dye in the system was not varied by the variation of temperature.

Photocatalytic hydrophilic treatment of polyester surfaces is investigated using TiO2 as a photocatalyst. The hydrophilicity of photocatalyzed polyester film and fabric is evaluated by means of water absorbency, contact angles, and XPS analyses. Irradiation of uv light with an approximate wavelength of 352 nm produces effective photocatalytic action of TiO2 on polyester. The surface properties of photocatalyzed polyester materials significantly improve and show high hydrophilicity. XPS analysis also indicates that the photocatalytic reaction of TiO2 generates C—O and C==O groups on the surface of polyester.

The characteristics of the running of color (“nijimi”) were quantitatively analyzed in order to elucidate the difference of natural indigo dyeing and conventional synthetic indigo dyeing. The luminance distribution curves and half-widths of the running of color were evaluated for the clothes tie-dyed with traditional natural indigo and conventional synthetic indigo. A single Gaussian function fits to the profile of the running of color produced by natural indigo reduced by fermentation, while the running of color produced by synthetic indigo prepared with sodium hydrosulfite was approximately represented by a linear sum of two Gaussian functions. The half-width profile of the running of color is in the following order : synthetic indigo ⁄ reduction method (sodium hydrosulfite) > synthetic indigo ⁄ reduction method (zinc powder) > natural indigo ⁄ reduction method (fermentation). The running of color is thus concluded to be due to the mode of indigo penetration into fiber, which depends on dyebath preparation. A critical difference in dyeing process is the speed of reduction of indigo, and could not be attributed to a small amount of impurity contained in natural indigo.

The effects of washing on color were quantitatively examined using a colorimeter to elucidate subtle color difference between cotton cloth samples dyed with natural indigo and synthetic indigo. Color produced by reactive dye and indigo was also compared and the results were analyzed by a CIELAB color system. Color unevenness was subjectively evaluated by seven professional indigo dyers. With repeated washing, L* value in cloth dyed with natural indigo increased at a lower rate than in cloth dyed with synthetic indigo. Color unevenness is related to dye absorption and dye aggregation.

Color reflectance from the cloth dyed with natural indigo was quantitatively compared with that from the cloth dyed with synthetic indigo by the spectrophotometric method, and the results were analyzed by a CIELAB color system. The cause of the color difference between the clothes dyed with natural and synthetic indigo was attributed to the mode of dye dispersion in fiber resulted from the aggregation of dye molecules during the reduction process. The results are summarized as follows: 1) The color produced by natural indigo is bluer and brighter than color produced by synthetic indigo reduced by sodium hydrosulfite. 2) The color produced by synthetic indigo using zinc powder is more similar to the color of natural indigo than the color of synthetic indigo prepared with sodium hydrosulfite. 3) The chroma and hue of the cloth dyed with natural indigo are higher than the respective values of the cloth dyed with synthetic indigo reduced by sodium hydrosulfite when the clothes are dyed repeatedly. 4) The diffusion coefficient of synthetic indigo reduced by sodium hydrosulfite is higher than that of natural indigo, where the diffusion coefficient of synthetic indigo reduced by zinc powder is similar to that of natural indigo.

Fixation of chitosan on cellulosic fabrics with using a cross-linking reaction of polycarboxylic acid has been investigated. Cotton fabrics that was cross-linked with polycarboxylic acid such as citric acid (CA) and butanetetracarboxylic acid (BTCA) showed to have appreciable amount of free carboxylic acid residues on the fabric that came from the polycarboxylic acid without participating the cross-linking reaction. Chitosan could be fixed on the fabric with good fastness to acid washing by padding and following curing process. Relatively high wrinkle recovery characteristics of the cross-linked and chitosan fixed fabric was obtained. The fixation of the chitosan on cotton fabric could also be done by the simpler process that consists of padding of mixture of polycarboxylic acid and chitosan onto untreated cotton fabric followed by high-temperature curing. With this process, simultaneous chitosan fixation could be achieved with the cross-linking reaction of polycarboxylic acid with cotton substrate. Intermolecular ester linkage formation by the polycarboxylic acid was suggested by the FTIR measurements.

Color fastness of a wool fabric that was low-temperature air-plasma treated and dyed with an acid dye has been evaluated. Color fading of the plasma treated fabric by carbon arc light irradiation was lesser at initial stage than that of the fabric without plasma treatment. The oxidized substrate through the plasma treatment may inhibit the photo-reduction reaction of the dye. Color fastness of the plasma treated fabric to laundering was poorer than that of untreated fabric. The phenomena may be attributed to an enhancement of dye diffusion in wool substrate by relaxation of intercellular material of wool by the plasma treatment.

Colorimetric determination method of D-galacturonic acid in reverse micellar solution has been investigated in order to assay pectinase catalyzed enzymatic hydrolysis of pectin in reverse micellar solution as a model study for bio-scouring of cotton in organic media. D-galacturonic acid produced by the hydrolysis of pectin could be detected by a specific condensation reaction with naphthoresorcinol. Condensation products showed clear blue color in reverse micellar solution that can be monitored by a spectroscopic determination method. Apparent rate of hydrolysis of pectin with pectinase enzyme in the reverse micellar solution obtained by the spectroscopic determination method was found to be slower than that in aqueous media, whereas the apparent rate of removal of the pectin from cotton fabrics by the pectinase assisted bio-scouring process in reverse micellar system was appreciably faster than that in aqueous media. The above difference between the results from the model study and from the practical bio-souring study would be attributed to the influence of cotton wax exist on actual cotton substrate that acts as gluing material for pectin and inhibit hydrolysis of pectic substances. Quick removal of cotton wax must be taken into account in the bio-scouring process to obtain effective scouring results.

Polyester (PET) fabrics were alcoholyzed at 90°C in triethylene glycol (TEG) or diethylene glycol (DEG) in the presence of 2% (wt/wt) of the corresponding sodium alkoxide, STEG or SDEG, or in ethylene glycol (EG) or glycerol (GR) in the presence of 2% (wt/wt) of sodium carbonate (SC) and the rate of the weight loss of the fabrics by the alcoholysis was studied in comparison with that by hydrolysis with a 10% (wt/wt) aqueous sodium hydroxide solution at 100°C. Alcoholysis with a EG solution in the presence of 1% (wt/wt) of calcium oxide (CO) was also studied at 100°C. The weight loss proceeded linearly with treating time (zero-order reaction) as with alkaline hydrolysis. The rate of the weight loss increased in the order: SC-GR< SC-EG

Fixation of chitosan on cotton and poly (ethylene telephthalate) (PET) fabrics irradiated with ultraviolet (UV) light was studied. The amount of chitosan fixed on UV-irradiated fabrics was found to be appreciably higher than that on fabrics that did not undergo irradiation. In comparing the fixation of chitosan on chemically oxidized cotton fabrics that contain large amounts of aldehydes and carboxyl groups, it can be deduced that electrostatic interactions between chitosan and carboxyl groups formed on the UV-irradiated fabrics may be involved in the fixation reaction. We were able to obtain chitosan fixation durable enough to withstand washing. A similar fixation effect was also observed on fabrics that were treated with low temperature air plasma.

In recent years, the soft-switching techniques have attracted attention for its peculiar advantages such as low swtching loss, high-power density, EMI/RFI noise reduction and so on. Authors have already reported before about quasiresonant DC-DC converter using new phase-shift PWM control scheme. By using proposed control scheme, circulating current is elimineted and ZVS (Zero Voltage Switchig) is achieved with small commutating current. As a result, the conduction losses caused by their currents are substantially reduced.In this paper, authors apply a proposed control scheme to a quasi-resonant high-frequency transformer link DC-AC converter. As a result, all switching devices in this DC-AC converter can achieve soft-switching with small commutating current irrespectively of inverter mode and rectifier mode. Its operating principle and unique features are described as compared with the symmetrical control scheme of DC-ACconverter. Operating performance of this DC-AC converter in steady-state are illutrated by means of simulating results.

Rate of weight loss of cellulosic fiber substrate by cellulase treatment was studied. The weight loss curves of cellulosic substrates by the cellulase treatment could be classified into two types. Fabrics of staple fibers such as cotton and linen broadcloths showed a weight loss curve that had at least two stages in weight loss process, whereas fabrics of filaments such as rayon taffetacloth showed a simple smooth decay curve. The two stages in the weight loss process of the fabrics of staple fibers could be attributed to the enzymatic hydrolysis and the mechanical removal of fuzz from the surface of the fabrics during the cellulase treatment. The weight loss curves of all cellulosic fabrics studied could be fitted to a linear combination of first order decay equation by a non-linear regression with high accuracy. Effects of cellulase concentration, mechanical action of treating apparatus and nature of surface of the fabrics on the rate of weight loss could be apparently represented by the simple decay equation.

Two kinds of poly (ethylene terephthalate) fibers, regular and partially oriented yarns, were heat set at 100°C-220°C in the unstressed state and then alkali hydrolyzed with 10% aqueous NaOH solution at 90°C. The rate of hydrolysis of the fibers with alkali was found to depend on heat setting temperature, i.e., weight loss initially decreased with increasing heat setting temperature up to 140°C and then increased at high temperatures. Shrinkage, disperse dyeing property, crystallinity and X-ray diffraction patterns were also measured with respect to the changes in the fine structure of fiber during heat treatment and alkali hydrolysis.

Poly (ethylene terephthalate) partially oriented yarn (PET POY) was heat set at 100 to 220°c in a fixed state and then treated with hydrazine. Although crystallinity of the heat-set PET POY increased with increased heat-setting temperature, weight loss from the hydrazine treatment initially decreased at a temperature up to 120°c and subsequently increased above 120°c. The hydrazinolyzed POY fiber is dyeable with acid dyes because of the hydrazide groups incorporated by hydrazinolysis. Nitrogen content and dye exhaustion with CI acid orange 7 showed trends similar to the weight loss of the hydrazinolyzed POY fibers. On the other hand, the dyeability of the hydrazinolyzed POY fibers with CI disperse violet 1 was lower than that of the untreated fibers. Many cracks appeared on the surface of the hydrazinolyzed fibers, and they were smallest on the fibers that were heat set at 120°c.

States of the solubilized water in reverse micellar solution of aerosol-OT (AOT, bis(2-ethylhexyl) sodium sulfosuccinate) in isooctane were investigated by determining the apparent molar volume of water, Vw, through density measurements at different temperatures and water contents wo ([H2O]/[AOT]) of the solution. The low Vw values in the range up to wo = ∼ 2 are due to the strong interaction of H2O molecules with the ionic headgroup of AOT. Then, Vw exhibits a steep rise with water content in the range of wo = 2−6 owing to the swelling of the spherical reverse micelle, which is caused by the weaker binding of the additional water molecules to the ester group of AOT. In the range of wo = 6−12, Vw exhibits a complex behavior as a function of the water content with a distinct minimum in the vicinity of wo = 10. This nonmonotonic course of Vw as a function of water content in this range cannot be rationalized in terms of monotonic changes of the characteristics of the solubilized water in the micelle, or in ...

Arterial tonometry is a technique used to measure arterial blood pressure noninvasively. The authors developed a new tonometer system containing an array of 15 piezoresistive pressure transducers, a mechanical positioning system, signal conditioning and multiplexing electronics, and a display and control console. The authors evaluated the accuracy, reliability, and clinical acceptability of this system by comparing tonometric blood pressure measurements with intraarterial blood pressure measurements in 60 anesthetized patients. Blood pressure was measured intraarterially in either the right or left radial artery by a Gould P23XL calibrated transducer, whereas blood pressure was measured by tonometer at the radial artery of the other arm. The tonometric waveform was similar to the intraarterial waveform. Simultaneous tonometer and intraarterial systolic blood pressures of the 60 patients (3,036 data sets) had an overall regression coefficient, r = 0.97, and an equation, regression equation = 0.95X + 5.8. Similar values were obtained for mean and diastolic pressures. Regression analyses of the paired tonometric and intraarterial blood pressure values showed good correlations in both sexes and in ages ranging from 8 to 82 yr (r = 0.94-0.97). Mean absolute values of error (precision) for the systolic, mean, and diastolic measurements did not differ significantly among the five systolic, five mean, and four diastolic pressure groups and ranged from 3.6 to 6.6 mmHg, with negligible bias, with intraarterial pressure used as the reference. Bias for the various pressure groups was small: -0.9-3.6 mmHg for systolic; -3.0-0.7 mmHg for mean; and -2.1-4.5 mmHg for diastolic. The "limits of agreement" (mean difference +/- two standard deviations) were within an acceptable range for clinical anesthesia.(ABSTRACT TRUNCATED AT 250 WORDS)

The methods to analyze the color of dyed or printed materials utilizing computer image analyzing systems were studied. Spectral reflectance curves and tristimulus values of the samples could be obtained as two dimensional data from the image of the sample. The reflection image of the sample was filtered and spectrally divided with 20 types of interference monochromatic glass filters (20 nm intervals, 400 - 780 nm) to 20 divisions of monochromatic images. Each monochromatic image was recorded by video camera, digitalized, and stored on the computer memories. From the images on the memories, spectral reflectance curve and CIE-XYZ tristimulus values at any point of the sample could be obtained with high accuracy. The technique could be applied to the quantitative analysis of the colorant absorbed on a solid substrate. The image of the sample formed by monochromatic reflection was converted to that formed by K/S values by computer calculation using the Kubelka-Munk equation. Since an intensity at any point in the K/S image could be related to the density of colorant at the corresponding point of the sample, the integration of the intensities of K/S image over enfire surface represents the total amount of colorant on the sample. Some examples of the method were demonstrated.

The authors evaluated the effi ciency and reproducibility of cardiac output measurement by esophageal continuous-wave Doppler ultra sonography (ECO). A total of 114 si multaneous measurements of ECO and thermodilution cardiac output (TDCO) were compared in 25 surgi cal patients undergoing general anes thesia in the supine position. ECO could be obtained easily with mini mal experience by means of a com mercially available Doppler cardiac output monitor. There was a signifi cant correlation between ECO and TDCO (

先天性第V因子欠乏症を合併する小児の口蓋裂形成術の麻酔管理を経験した.手術に先立ち正常血漿添加試験を行い,活性部分トロンボプラスチン時間(APTT)が第V因子活性の指標として有用であること,血漿添加によりAPTTが短縮されることを確認した.術中の第V因子補充療法として新鮮凍結血漿(FFP)投与を行い,初回補充として20ml/kg投与した.小児患者では循環系に対する容量負荷が懸念されることからFFP投与と同時に脱血を行った.初回投与後にAPTT値が40秒と改善したのを確認後,手術を開始した.術後2日間に10ml/kgのFFP追加投与を2回行いAPTT値を50秒以下に維持し,全経過を通じ異常な出血をみることもなく良好な経過を得た.

Poly (p-phenylene terephthalamide) films, poly (phenylene sulfide) films and poly (m-phenylene isophthalamide) fibers were irradiated with a XeCl excimer laser to modify their surface structure. The change in surface morphology of laser-irradiated polymer materials was found to be dependent on the laser irradiation angle. At an irradiation angle of 60° or 45°, anisotropic roll -like structure was created by the laser ablation. The friction coefficient of the poly (m-phenylene isophthalamide) fibers changed with the laser irradiation angle. The fibers irradiated at an irradiation angle of 90° did not show any directionality in the friction coefficient, while the fibers irradiated at an angle of 60° or 45° showed the directionality in the friction coefficient.