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A two-level factorial design was set up where five factors in a kraft paper process were varied, from wood chip origin to paper machine roll pressure. Nine paper properties were selected for a more ...

By investigating how properties of a finished paper product are related to different process variables as well as pulp characteristics throughout the fiber line, the understanding of the process will increase. In this paper we investigate the correlation between some key paper quality parameters and five tunable process variables, along the entire fiber production line. A full two-level factorial experiment has been conducted, where five factors were varied. The factor settings were based on a laboratory replica of a specific kraft mill’s paper product. The mill replicate was then used as a center point in the factorial design and appropriate levels of the factors were set based on these center points. Several experimental runs could be simulated via a Monte Carlo approach making it possible to get a reliable estimate of the significance of each factor effect. Analysis of the results shows that there are interaction effects present between variables, and that these interaction effects can be utilized to achieve similar paper properties using different variable settings.

In this paper we correct a mistake in [C. Ciliberto, F. Russo, On surfaces with two apparent double points. Adv. Geom. 5 (2005), 223–235].

In this paper we correct an inaccuracy that appears in the proof of Theorem 1. in Czerwik's article "Contraction mappings in $b$-metric spaces.", Acta Math. Inform. Univ. Ostraviensis, 1:5--11, 1993., 3 pages

Pulp and paper industries have provided great research opportunities to control systems. The objective of this study was to investigate the relationships between 80 process variables of CMP tower and stock preparation, and 17 newsprint quality properties in Mazandaran Wood and Paper Industries (MWPI). After the preparation of two suitable data series considering the time needed for pulp to paper, the relations between process dependent and newsprint independent variables were determined using partial least squares (PLS) regression. As a result, two PLS models were developed. The first model with 4 latent vectors categorized and related CMP tower variables and the second one, through 8 latent vectors connected stock preparation variables with paper properties. PLS regression coefficients determined how much the most influencing process variables impact each paper properties

A new method is reported for measuring the short span stress-strain curve of paper using a zero/short span tester with additional instrumentation to measure load and displacement during a test. The method is to subtract the zero-span displacement-load curve from the short-span displacement-load curve, so as to obtain the displacement-load curve of the free span. An analysis of the short span test shows that if the sample is well-bonded and the free span is small compared to the fibre length, then the stress-strain behaviour of the free span is independent of span. The new method was used to examine the effect of refining on the short span stress-strain curve of a paper made from an unbleached, never-dried commercial Scandinavian softwood kraft. The breaking strain increased from 12% for sheets made from the unrefined pulp to 23% for sheets made from pulp refined to 6,000 PFI revolutions.

A model for the web consolidation process in the paper dryer is developed and compared with experimental data for the kraft pulps. The model contains one parameter called the shrinkage factor which is used as the fitting parameter to the experimental data. The shrinkage factor can have a value between zero implying no shrinkage and a value of one which implies that all the liquid volume removed leads to shrinkage. The fitted shrinkage factor is below unity in all experiments with kraft pulps except one. This indicates that not all the removed liquid causes shrinkage. The fact that the shrinkage is higher than for ideal shrinkage (which assumes that all the water removed leads to shrinkage), can be caused by the assumption that the liquid is only located in the non-gaseous phase, and thus spreads over a smaller area than the total surface area. The results for the new model were compared with three previous models from the literature. Taking the whole range of beating degrees into account the new model showed the best agreement with the experimental data. (Less)

This expository paper presents known results on distribution functions g(x) of the sequence of blocks where xn is an increasing sequence of positive integers. Also presents results of the set G(Xn) of all distribution functions g(x). Specially: - continuity of g(x); - connectivity of G(Xn); - singleton of G(Xn); - one-step g(x); - uniform distribution of Xn, n = 1, 2, . . . ; - lower and upper bounds of g(x); - applications to bounds of ; - many examples, e.g., , where pn is the nth prime, is uniformly distributed. The present results have been published by 25 papers of several authors between 2001-2013.

On a recent paper Benchohra and Mostefai [2] presented some existence results for an integral equation of fractional order with multiple time delay in Banach spaces. In contrast to the classical case, when assumptions are expressed in terms of the strong topology, they considered another case, namely with the weak topology. It has some consequences for the proof. We present here some comments and corrections.

In this paper we improve Theorem 7 in [1] which deals with the existence and uniqueness of solutions of the three dimensional globally modified Navier-Stokes equations.

We deduce new properties of the orbicyclic function $E$ of several variables investigated in a recent paper by V. A. Liskovets. We point out that the function $E$ and its connection to the number of solutions of certain linear congruences occur in the literature in a slightly different form. We investigate another similar function considered by Deitmar, Koyama and Kurokawa by studying analytic properties of some zeta functions of Igusa type. Simple number theoretic proofs for some known properties are also given., Comment: 10 pages

In 2002, F. Luca and P. G. Walsh studied the Diophantine equations of the form (

This note gives the correct form of a result (Theorem 2, p. 478) published recently in [Math. Slovaca 60 (2010), 471–484].

The goal of this paper is to model the pulp properties fiber length, shives width and freeness. This will be done utilizing specific energy, flat zone inlet consistency and the internal variables, consistencies and fiber residence times estimated from refining zone soft sensors. The models are designed using more than 3600 hours of data from a RGP82CD refiner. The pulp properties are sampled using a measurement device positioned after the latency chest. Such measurements are noisy and irregularly sampled which opens for a number of challenges to overcome in modeling procedures. In this paper it is shown that the models for shives width and fiber length are capable of predicting most of the major dynamics. However, for freeness no reliable linear models can be derived. When estimating fiber length, the specific energy together with flat zone inlet consistency, fiber residence times and the consistency in the conical zone were the dominant inputs. For shives width it was found that a similar set of inputs resulted in the best models, except that the consistencies during normal process conditions did not significantly influence shives width. Furthermore, fiber residence times were shown to have considerably more pronounced impact on fiber length compared with shives width estimates.

In a recent paper [1] S. Golden is trying an interpretation of Einstein's theory of special relativity solely based on the propagation of light-pulses which aims at circumventing the problems scientists sometimes do have with the "twin paradox", i.e. with the physical reality of the kinematical dilation-of-time. However it is well known that propagation of light does not cover the whole structure of relativistic spacetime because of the conformal invariance of the Maxwell equations. Thus the paper [1] is fundamentally incomplete in its applied physical tools. In my comment it will be shown that the title of the paper is a misconception and that another aspect in the paper is false too. If S. Golden would have treated in the paper not only light-pulses but also decaying systems the shortcomings would not have occurred. The sole tool of the author for relating inertial systems is the exchange of light-pulses (including reflections) between two inertial systems, called A-system and B-system, with time coordinates t and r, respectively. The light-pulses are propagating either into the direction of the inertial-systems relative velocity or into the opposite direction. No doubt, the ratio At/AT of the time-intervals between fixed-position (origins of the systems) passage-times of the same two light-pulses in the A-system and in the B-system is given by, combine the Eqs. (6) and (12) in the paper in question

In his comment G. Schäfer [1] points out that S. Golden's [2] time-dilation equations (12) and (13) are of kinematic type and that the title of Golden's paper is therefore a misconception. He also states that Golden's treatment of the time-dilation problem is incomplete, since Golden has not considered particle decay in his paper. I should like to present my comment on these two points raised by G. Schäfer. Although Golden describes his equation (13) as "spatially dependent," he says at the beginning of Sect. 4 of his paper that his equations (12) and (13) can be regarded as "either velocity dependent or spatially dependent." But this is not at all the essence of his paper. The essence of his paper is that the two time-dilation equations that he has derived do not imply "any actual dilation-of-time in clocks that may be stationed in the systems." Hence he concludes that Einstein's time-dilation relation is merely a transformation relation and that the motion of the systems does not affect "the intrinsic time-rates of any clocks stationed within them." In order to judge the significance of Golden's paper, it is important to remember that Einstein arrived at the ideas of kinematic time-dilation and length contraction in moving systems not as a result of a rigorous deduction from any mathematical, physical or logical relations, but simply by interpreting in his own way the physical significance of transformation equations for space and time (Lorentz transformation equations) [3]. Ever since the publication of his 1905 article, Einstein's ideas of kinematic length contraction and time dilation

Internal variables in (C)TMP-refining processes (e. g. temperature, consistency, fiber residence time, backward flowing steam and forces acting upon the chips and pulp) are defined as physical states obtained in different parts of the refining zones. In short, they differ from the traditional external variables (e. g. dilution water feed rate and specific energy) which are not obtained from measurements or physical models of the process in the refining zone. The internal variables are the backbone of physical models and are used in this paper as soft sensors for advanced process control. Besides the shape of the temperature profile, the position of the maximum temperature and the shape of the consistency profiles inside the refining zones are important to control as they are directly linked to the development of different pulp and handsheet properties. To illustrate the capability when using combined modeling and control strategies, the concept is applied on a full scale CD82 refiner. This means both temperature and consistency control in the flat zone and the conical zone, together with an overall estimator for fiber development. Finally, in this paper it is shown that the production can be increased significantly without changing the refiner motor load nor violating the pulp property specification.

The objective of this study is to analyze and foresee potential outliers in pulp and handsheet properties for larger data sets. The method is divided into two parts comprising a generalized Extreme Studentized Deviate (ESD) procedure for laboratory data followed by an analysis of the findings using a multivariable model based on internal variables (i. e. process variables like consistency and fiber residence time inside the refiner) as predictors. The process data used in this has been obtained from CD-82 refiners and from a laboratory test program perspective, the test series were extensive. In the procedure more than 290 samples were analyzed to get a stable outlier detection. Note, this set was obtained from pulp at one specific operating condition. When comparing such “secured data sets” with process data it is shown that an extended procedure must be performed to get data sets which cover different operating points. Here 100 pulp samples at different process conditions were analyzed. It is shown that only about 60 percent of all tensile index measurements were accepted in the procedure which indicates the need to oversample when performing extensive trials to get reliable pulp and handsheet properties in TMP and CTMP processes.

This paper presents a case study of sound symbolism, cases in which certain sounds tend to be associated with particular meanings. We used the corpus of all Japanese Pokémon names available as of October 2016. We tested the effects of voiced obstruents, mora counts, and vowel quality on Pokémon characters' size, weight, strength parameters, and evolution levels. We found that the number of voiced obstruents in Pokémon names correlates positively with size, weight, evolution levels, and general strength parameters, except for speed. We argue that this result is compatible with the frequency code hypothesis of Ohala. The number of moras in Pokémon names correlates positively with size, weight, evolution levels, and all strength parameters. Vowel height is also shown to have an influence on size and weight - Pokémon characters with initial high vowels tend to be smaller and lighter, although the effect size is not very large. Not only does this paper offer a new case study of sound symbolism, it provides evidence that sound symbolism is at work when naming proper nouns.

Seven-hundred kilograms of subtropical Barki wool was collected to study the effect of a subjective grading system and blending with polyester on selected wool and yarn characteristics. Wool was graded subjectively into coarse, fine and raw; then each grade was blended with 0%, 15%, 25%, 35% and 45% of polyester. Staple and yarn strengths were higher in both coarse and fine grades compared with raw wool. Staple elongation of the fine grade reached 3 times that of coarse grade and twice as much as raw grade. Also, in the 100% wool blend, yarn elongation of the fine grade was twice as much as both coarse and raw grades. The fine grade had the highest yarn friction, followed by other grades. Generally, adding polyester to coarse and fine grades led to an improved yarn strength compared with the raw grade. Adding 15% polyester caused the highest improvement among other percentages. Correlations among traits were also discussed.

In this study, the effects of low consistency refining (LCR) energy and intensity on mechanical pulp properties have been studied for three different types of reject pulps (softwood TMP, softwood CTMP and hardwood CTMP), which were refined at varying intensity. Resulting pulp properties have been compared with high consistency refining (HCR) of the same reject pulps. For all furnish types, it was shown that LCR can develop pulp properties matching those developed through HCR with significantly less energy. The resulting pulp properties were found to be affected not only by refining intensity and energy, but also by initial fibre morphology. Pilot LCR trials demonstrated that high freeness reject pulp is initially insensitive to refining intensity as specific energy is applied. This enables the first stage of LCR to be carried out at a higher specific energy and intensity, which can reduce the number of stages of LCR required to reach a target quality. This work shows that low intensity LCR is capable of achieving the same tensile index as HCR pulp at a target freeness of 200 ml CSF.

The evenness of raw silk is one of its most valuable qualities. Seriplane inspection is a common test for raw silk evenness but is prone to human error and lacks accurate repeatability; the Uster evenness tester is another common approach but is costly and vulnerable to environmental factors. An image-based raw silk evenness detection system is proposed in this paper. The system is comprised of an image acquisition segment with a CCD image sensor, telecentric lens, light source, over feeding device, and raw silk winding device, plus an image processing segment tasked with threshold segmentation and morphology operations. Images of the raw silk are first captured with the image acquisition segment, then the images are processed by threshold segmentation and morphology processing; the diameters obtained in this segment are then used to calculate the variation coefficient (CV), which characterises the evenness of the raw silk. We conducted three experiments to test the stability, repeatability, and accuracy of the system. The results showed that the system proposed is stable, repeatable, and accurate.

The objective of the paper was assessment of the selected qualities of carrot from retailer's shops, organic and traditional food shops in Krakow. The following quality parameters of the fruit pulp were investigated: content of extract, sugars, polyphenols, nitrite, flavonoids, beta-carotene, colour, and antioxidant activity. The investigation shows that the content of nitrogen (V) in the samples of carrot from traditional cultivations was higher than in case of carrot from organic crops, and in case of a sample from traditional cultivation it exceeds the admissible norms. However, the research which was carried out provides no justification for the statement that the content of nitrate (III) depends on the production system of carrot. The research on the content of polyphenols, flavonoids and antioxidant activity of juice proved the increased antioxidant ability of carrot that was traditionally cultivated with reference to carrot cultivated organically. However, the differences were not statistically confirmed. Beta-carotene content in all samples was comparable regardless the cultivation system. Content of extracts, total carbohydrates and sucrose was significantly higher for carrot from traditional crops than for eco-carrot.