A framework for analysis of the effect of time on shopping behavior

Due to technological developments, data about how many items a customer buys and how long the customer spends in a supermarket are available. A major problem with the data, however, is that there is no framework that considers the heterogeneity hidden in the data. In this article, we propose a framework that considers heterogeneity in the number of items a customer buys. The first step of our framework is based on the Poisson mixture regression model using a stationary time in the department where the items are sold as its independent variable. This model finds latent homogeneous groups of customers and gives the regression models within each group. It simultaneously classifies the customers into the homogeneous groups. In the second step of our framework, a method to investigate whether another factor (variable) influences the classification into homogeneous groups is presented. This proposed framework is applied to real data collected from the customers, and the effectiveness of the framework is shown. The managerial implications are drawn from the result of the analysis.     

Toward a quizmaster robot for speech-based multiparty interaction

This paper presents an interactive quizmaster robot that can manage a multiparty speech-based quiz game. The basic flow of the quiz game is that (1) the robot reads a question, (2) one or more players answer it, and (3) the robot judges the correctness of the answers. We categorize such speech-based quiz games into school-type interaction and auction-type interaction. The former asks players to say ‘Yes’ to get the right to answer before answering a question and the latter allows players to directly answer a question without any advance notice. To realize such interaction, the robot needs the capability of recognizing utterances from multiple people using its own microphones (i.e. ears), even if those utterances are made simultaneously. To cope with such situations, the robot estimates which player made the fastest utterance and recognizes it by localizing and separating a mixture of audio signals. Experiments were conducted to evaluate the success rates of the fastest player identification and speech recognition. The results showed that the robot could identify the fastest speakers with a success rate of 90.0% more accurately than humans when only one speaker slightly preceded the other speakers. We found that although the success rate of speech recognition for the fastest speakers did not reach that of humans, the robot attains amusing quiz game interaction.     

Genetic Profiling of Malignant Melanoma Arising from an Ovarian Mature Cystic Teratoma: A Case Report

Ovarian mature cystic teratomas comprise tissues derived from all three germ layers. In rare cases, malignant tumors arise from ovarian mature cystic teratoma. A variety of tumors can arise from mature cystic teratoma, among which primary malignant melanoma (MM), for which no molecular analyses such as genomic sequencing have been reported to date, is exceedingly rare, thereby limiting possible therapeutic options using precision medicine. We used targeted gene sequencing to analyze the status of 160 cancer-related genes in a patient with MM arising from an ovarian mature cystic teratoma (MM-MCT). KRAS amplification and homozygous deletion in PTEN and RB1 were detected in tumor samples collected from the patient. No KRAS amplification has been previously reported in cutaneous MM, indicating that the carcinogenesis of MM-MCT differs from that of primary cutaneous melanomas. A better understanding of the underlying genetic mechanisms will help clarify the carcinogenesis of MM-MCT. In turn, this will enable treatment with novel targeting agents as well as the initial exploration of gene-based precision oncological therapies, which aim to improve treatment outcomes for patients with this disease.     

Adsorptive removal of As(V) and As(III) from water by a Zr(IV)-loaded orange waste gel

Orange waste, produced during juicing has been loaded with zirconium(IV) so as to examine its adsorption behavior for both As(V) and As(III) from an aquatic environment. Immobilization of zirconium onto the orange waste creates a very good adsorbent for arsenic. Adsorption kinetics of As(V) at different concentrations are well described in terms of pseudo-second-order rate equation with respect to adsorption capacity and correlation coefficients. Arsenate was strongly adsorbed in the pH range from 2 to 6, while arsenite was strongly adsorbed between pH 9 and 10. Moreover, equimolar (0.27 mM) addition of other anionic species such as chloride, carbonate, and sulfate had no influence on the adsorption of arsenate and arsenite. The maximum adsorption capacity of the Zr(IV)-loaded SOW gel was evaluated as 88 mg/g and 130 mg/g for As(V) and As(III), respectively. Column adsorption tests suggested that complete removal of arsenic was achievable at up to 120 Bed Volumes (BV) for As(V) and 8 0BV for As(III). Elution of both arsenate and arsenite was accomplished using 1 M NaOH without any leakage of the loaded zirconium. Thus this efficient and abundant bio-waste could be successfully employed for the remediation of an aquatic environment polluted with arsenic.     

Synthesis and characterization of a series of mesoporous nanocrystalline lanthanides phosphate

A series of lanthanide (LA) phosphate were prepared by using N-(2-hydroxyethyl) ethylenediane-N,N′,N′-triacetic acid (H₃hedtra) as a chelating agent. The obtained samples were characterized by using X-ray diffraction (XRD), nitrogen adsorption-desorption isotherm, thermal analysis (TG-DTA), transmission electron microscope (TEM) and TPD-ammonia desorption. The results showed that samples prepared through chelating agent route possessed smaller particle size which led to higher specific surface area with increased acidic sites compared with the reference samples prepared free of H₃hedtra. It was also found that the acidic strength increased gradually from the light lanthanide phosphate to heavy lanthanide phosphate. Besides, pore size of the samples could be controlled by altering the mole ratio of the lanthanide(LA): H₃hedtra. Pore size distribution of the samples became narrower through synthesis in the presence of H₃hedtra. The precursor sol complex was investigated by FTIR and XRD and mesopore formation mechanism had been discussed.     

Influence of calcination procedure on the catalytic property of sulfated zirconia

Calcination parameters, such as atmosphere, duration and catalyst bed depth have a marked influence on the catalytic and spectroscopic properties of sulfated zirconia. Sulfated zirconia calcined in nitrogen or synthetic airflow, in deep bed, exhibited comparable activity in n-butane isomerization at 373 K, which suggests that oxygen is not necessary for formation of active sites. Catalysts calcined in shallow bed are catalytically inactive. Thus, the bed depth is concluded to be crucial for the formation of active sites. The samples calcined in shallow bed possessed lower sulfate content and the S=O stretching vibration was located at lower frequency. Calcination in the presence of water vapor also led to lower catalytic activity, sulfate content, and BET area. Extended calcination reduced gradually the activity and the sulfate content, which underlines the labile property of the active sites. A new interpretation of the function of the calcination step is proposed and compared with models described in the literature.     

Assessment of the offshore wind resource in Japan with the ASCAT microwave scatterometer

We analysed wind speed and direction off the coast of Japan using data from the satellite-borne Advanced Scatterometer (ASCAT) and the Weather Research and Forecasting model (WRF), validated these data using in situ wind measurements from 20 buoys, and evaluated the effect of the long time intervals from ASCAT observations on wind resource assessment. More than 25 km from the coast, and at heights of 10 m, the ASCAT wind speed has negative biases of up to 3.4% and root mean square errors of up to 18.5%; its wind direction has 11° to 27° of mean absolute error compared to buoy measurements at a height of 10 m. These accuracies are better than either the expected accuracies reported in the technical manual or those simulated with WRF with its spatial resolution of 10 km. We also evaluated long-term average ASCAT wind speeds in comparison to 4- and 5-year averages of in situ buoy wind speeds measured at three buoys, with resulting differences of –0.3%, –6.3%, and – 1.6%. Furthermore, wind roses show that appearance frequencies of the ASCAT wind direction for the long term are in a good agreement with those of the measurements at the three buoys. Our results show that the ASCAT-derived wind speed and direction are appropriate more than 25 km from the coast, and that the long time interval between ASCAT observations has an insignificant effect on wind resource assessment, if at least 4 or 5 years of averaged ASCAT data are used.     

Estimation of heat of dilution of polymer solution: a trial on a correction of the heat of stirring ascribed to the viscosity difference before and after dilution

The heat of dilution for the polystyrene and methyl ethyl ketone system was measured using an isothermal calorimeter, and the heat correction due to the change of stirring before and after dilution was estimated from the observed change in heat of dilution. The net heat of dilution of the polystyrene and methyl ethyl ketone system obtained was very small and the system was considered to be almost athermal. The heat correction due to the change of stirring was unexpectedly large, and often exceeded the net heat of dilution. The interaction parameters obtained for the polystyrene and methyl ethyl ketone system were +0·035, +0·012, ?0·022, and ?0·062 for molecular weights of 2100, 22 000, 57 500, and 212 000, respectively, at 298·15K.