Classification into homogeneous groups using combined cluster and discriminant analysis

The classification of observations into groups is a general procedure in modern research. However, when searching for homogeneous groups the difficulty of deciding whether further division of a classification is necessary or not to obtain the desired homogeneous groups arises. The presented method, Combined cluster and discriminant analysis (CCDA), aims to facilitate this decision.CCDA consists of three main steps: (I) a basic grouping procedure; (II) a core cycle where the goodness of preconceived and random classifications is determined; and (III) an evaluation step where a decision has to be made regarding division into sub-groups. These steps of the proposed method were implemented in R in a package, under the name of ccda.To present the applicability of the method, a case study on the water quality samples of Neusiedler See is presented, in which CCDA classified the 33 original sampling locations into 17 homogeneous groups, which could provide a starting point for a later recalibration of the lake's monitoring network.     

A partial binary tree DEA-DA cyclic classification model for decision makers in complex multi-attribute large-group interval-valued intuitionistic fuzzy decision-making problems

This paper proposes the idea of combining “interest groups” with the practical decision information to classify the decision makers (DMs) in complex multi-attribute large-group decision-making (CMALGDM) problems in interval-valued intuitionistic fuzzy (IVIF) environment. It constructs a partial binary tree DEA-DA cyclic classification model to achieve the multiple groups’ classification of DMs. Not only does this method provide references for the classification of DMs when the decision information is known, but it also lays foundations for DMs’ effective weight determination and the aggregation of decision information. First, this paper normalizes all of the cost attributes into benefit attributes to avoid the wrong decision result. Second, it employs the C-OWA operator to transform IVIF number (IVIFN) samples into single-valued samples. With respect to this transformation, this paper provides the corresponding BUM functions of DMs according to their risk attitudes; therefore, the preference information of DMs can be more objectively aggregated. Third, this paper adopts the partial binary tree DEA-DA cyclic classification model to present an accurate classification of DMs. Thus, for each interest group, group members with different interest preferences can be distinguished and distributed to the appropriate groups. Finally, to show the feasibility and validity of the model, we give an illustrative example.     

Can Our Group Survive? An Investigation of the Evolution of Mixed‐Mode Groups

Applying an ecological and evolutionary perspective, this study examines the evolution and the sustainability of “mixed‐mode groups,” a type of voluntary association created and organized online to interact physically in geographically defined ways. Meetup.com is a website that facilitates the creation and coordination of mixed‐mode groups. Analysis of interviews with 34 Meetup group organizers and a longitudinal analysis of 100 randomly selected Meetup groups revealed the evolutionary processes at the group and population level, respectively. Specifically, the ecological factor of population density, the demographic factor of group age, the group's profit orientation, experience of leadership change and shared leadership, and external ties played decisive roles in predicting group survival. Implications of the findings for theoretical and practical contributions are discussed.     

On extensions of subshifts by finite groups

λ-Graph systems are labelled Bratteli diagrams with shift operations. They present subshifts. Their matrix presentations are called symbolic matrix systems. We define skew products of λ-graph systems and study extensions of subshifts by finite groups. We prove that two canonical symbolic matrix systems are G-strong shift equivalent if and only if their presented subshifts are G-conjugate.     

Consumer Input for Developing Human Food Products Made with Sorghum Grain

Abstract: Because sorghum grain has important characteristics (for example, great antioxidant profile) for introduction into the regular human diet, producers and industry aim to develop successful products using sorghum as the base. The 1st step in developing products attractive for consumers is understanding consumer needs and expectations. Conjoint analysis determines attributes which may be important or unimportant for one product. In this study, focus groups and conjoint analysis were used to establish which attributes are helpful for promoting purchase intent of sorghum grain products. Once those characteristics were chosen, a national survey was conducted to confirm the selection. During the focus groups, the heath aspects of grain products seemed to be the most appealing for consumers, whereas conjoint analysis showed that sensory attributes were the principal drivers for purchase intent. Practical Application: The data presented in this study are essential for industry as a starting point for developing sorghum grain based food products. It is necessary to address consumers’ demands to ensure new products’ success in the market, and the present study clearly shows this consumers’ input.     

User perceptions of ICT impacts in Swedish construction companies: ‘it’s fine,just as it is’

The use of information and communication technologies (ICT) in construction companies has been growing steadily during the last decade. However, few studies inquire into either perceptions of the impact of actual ICT use or perceptions among different occupational groups in construction companies. The aim of the paper is to explore users’ general perceptions of ICT impacts in the post-adoption stage and analyse the implications for construction management practice. A mixed methods approach was used. Quantitative data were collected using a web-based survey both in a major construction company and among medium-sized companies in Sweden. Data from 294 returned completed questionnaires were analysed with t-tests and multiple regression analysis. In addition, participant observations and semi-structured interviews were conducted within the major construction company in order to strengthen the analysis. It can be concluded that respondents are generally fairly satisfied with the ICT. Differences in perceptions among occupational groups can be explained by the nature of work tasks and the original intentions for using ICT as a means of control and calculation. Even if respondents perceive that a further development of ICT could improve competitiveness, they do not want to increase their use of it in their workplaces. They basically think that ‘it is fine, just as it is’. This indicates that a challenge in construction management is to investigate how prevailing and new ICT applications can be used to develop the industry.     

黄河流域：商丘城市空间营造

该文是个案研究系列之泛黄河流域商丘城市空间营造研究,对商丘城市族群的更替叠累及城市空间营造进行了分析研究.     

Synergistic Role of Pumice Surface Composition in Hydroxyl Radical Initiation in the Catalytic Ozonation Process

This study investigated the catalytic ozonation of p-chloronitrobenzene (p-CNB) in aqueous solution by using different pumice surface compositions as catalysts. The results indicate that the surface hydroxyl groups of metal oxides on pumice play an important role in ozone decomposition to generate the hydroxyl radical (?OH). An increase in the mass ratio of SiO₂/metal oxides results in the acceleration of ozone adsorption on the catalyst surface. The synergistic mechanism confirms that SiO₂ induced ozone enrichment on the pumice surface and increased the probability of reaction between surface hydroxyl groups on metal oxides and ozone molecules to initiate ?OH from ozone decomposition and to stimulate p-CNB degradation.     

Novel chalcone-based aromatic polyamides: synthesis,characterization, and properties

Two novel diacid-based monomers have been synthesized by anchoring a benzylideneacetophenone (chalcone) moiety through an amide or ester bridge at the fifth position of the isophthalic acid ring. Two series of new polyamides bearing chalcone side chains were prepared by direct polycondensation reaction of the aforementioned dicarboxylic acids and various aromatic diamines in N-methyl-2-pyrrolidinone, using triphenyl phosphite and pyridine as condensing agents. Their molecular structure and the basic properties were investigated by nuclear magnetic resonance, Fourier-transform IR and UV–vis spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and wide-angle X-ray diffraction. The inherent viscosity, molecular weights measurements (by gel permeation chromatography), water uptake, and solubility tests completed the research study. Introduction of the rigid and bulky chalcone units into the polymer side chains improved remarkably the solubility of the aromatic polyamides, endowed them with an amorphous nature, good thermal stability, and photosensitivity. The resulting polymers were obtained in good yields, inherent viscosities varied between 0.49 and 0.86 dL/g, and their relative high molecular weights conferred them film-forming properties. They were soluble in amide-type polar solvents, such as N,N-dimethylformamide, dimethyl sulfoxide, N,N-dimethylacetamide, and N-methyl-2-pyrrolidone. These polyamides had glass transition temperatures between 219 and 264 °C, and 10% weight loss temperatures in the range of 394–436 °C and around 50% residue at 700 °C in nitrogen atmosphere. The polyamides underwent a [2 + 2] photocycloaddition reaction upon UV light irradiation both in solution and film state in the absence of a photoinitiator or photosensitizer. The polymer films became insoluble in solvents as a result of the crosslinking .     

霍林河煤田一号露天矿煤层显微煤岩特征

文中应用煤岩学方法 ,对霍林河煤田具代表性的 17号煤层的显微煤岩特征进行了系统研究 ,阐述了不同组分分布特征及其变化规律 ,并指出了煤的加工利用方向