bluuebunny/crossref_metadata_2025 huggingface dataset:
Bilateral Smell Preservation is Routinely Possible following Endoscopic Endonasal Approach for Sellar/Suprasellar Lesions
Authors: Ting Kuan-Chung , Wang Wei-Hsin , Kuan Edward C. , Lin Yung-Yang , Lan Ming-Ying
Published: November 2019

Objective The endoscopic endonasal approach (EEA) has been shown to be an effective means to access sellar lesions. However, there are limited studies centered on evaluating olfactory function after surgery. In this study, we assessed the pre- and postoperative olfactory function of patients who underwent EEA for sellar and suprasellar lesions. The impact of nasoseptal flap use on olfaction was further analyzed.

Study Design A retrospective study.

Setting A tertiary-care referral center in Taiwan.

Participants Patients with sellar and suprasellar lesions who underwent EEA and pre- and postoperative olfaction assessment from August 2015 to March 2018 were included in the study.

Main Outcome Measures The patients' olfactory function was examined pre-and postoperatively using the Sniffin' Sticks odor identification test. Data regarding demographics, olfactory scores, pathology, reconstructive technique, graft usage, and extent of resection were retrieved.

Results A total of 106 patients (36 males and 70 females) were enrolled, with a mean age of 51 years. There were 76 pituitary tumors, 12 Rathke's cleft cysts, 7 craniopharyngiomas, 7 meningiomas, and 4 other lesions. The nasoseptal flap was used in 39 patients for skull base reconstruction, and these patients had no statistically significant change between pre- and postoperative olfactory scores (p = 0.283). Moreover, a statistically significant improvement of olfactory scores was found in patients in whom the nasoseptal flap was not used.

Conclusion Olfactory function may be reliably preserved after EEA, with or without nasoseptal flap harvest and use.
Operative Times in Primary Total Knee Arthroplasty: Can We Predict the Future Based on Contemporary Nationwide Data
Authors: Sultan Assem A. , Samuel Linsen T. , Karnuta Jaret M. , Acuña Alexander J. , Mahmood Mustafa , Kamath Atul F.
Published: November 2019

Recently, the Centers for Medicare & Medicaid Services announced its decision to review “potentially misvalued” Current Procedural Terminology (CPT) codes, including those for primary total knee arthroplasty (TKA). CPT 27447 is being reevaluated to determine contemporary relative value units for work value, with operative time considered a primary factor in this revaluation. Despite broader indications for TKA, including extension of the procedure to more complex patient populations, it is unknown whether operative times may remain stable in the future. Therefore, the purpose of this study was to specifically evaluate future trends in TKA operative times across a large sample from a national database. The American College of Surgeons National Surgical Quality Improvement Project database was queried from January 1, 2008 to December 31, 2017 to identify 286,816 TKAs using the CPT code 27447. Our final analysis included 140,890 TKAs. Autoregressive integrated moving average forecasting models were built to predict 2- and 10-year operative times. While operative times were significantly different between American Society of Anesthesiologists (ASA) classes 1 and 2 (p = 0.035), there were not enough patients in ASA class 1 to perform rigorous inference. Additionally, operative times were not significantly different between ASA classes 3 and the combined ASA classes 4 and 5 cohort (p = 0.95). Therefore, we were only able to perform forecasts for ASA classes 2 and 3. Operative time was found to be nonstationary for both ASA class 2 (p = 0.08269) and class 3 (p = 0.2385). As a whole, the projection models indicated that operative time will remain within 2 minutes of the present operative time, up to the year 2027. Our projections indicate that operative times will remain stable over the next decade. This suggests that there is a lack of evidence for reducing the valuation of CPT code 27477 based on intraservice time for TKA. Further study should examine operative time trends in the setting of evolving alternative payment models, increasing patient complexity, and governmental restrictions.
2.1.2 Palladium/Organocatalyst Dual Catalysis
Authors: Vitale M. R.
Published: November 2019

This chapter describes the recent development of original asymmetric transformations based on the synergistic merger of palladium catalysis with organocatalysis. Thanks to this association, the orthogonal and complementary activation of different reaction partners has proven to be key to the discovery of efficient enantioselective catalytic processes that would not otherwise be possible. To illustrate this, several selected examples are discussed. The combination of πallylpalladium catalysis with organocatalysis allows a considerable widening of the scope of enantioselective allylic alkylation reactions of carbonyl-containing compounds. Moreover, innovative asymmetric arylation of aldehydes, ketones, and alkenes has also been developed. Finally, palladium/organocatalyst dual catalysis constitutes a unique opportunity for the discovery of new cycloaddition processes.
Study of multimode semiconductor lasers with buried mesas
Authors: Shamakhov V.V. , Nikolaev D.N. , Golovin V.S. , Veselov D.A. , Slipchenko S.O. , Pikhtin N.A.
Published: November 2019

A buried-mesa AlGaAs/GaAs/GaInAs laser heterostructure emitting at a wavelength of 1050 nm is formed on a GaAs substrate by MOCVD. Mesa-stripe laser diodes with an aperture of 100 μm based on the obtained heterostructure are fabricated and studied. The internal optical losses of the laser diodes are 2.4 cm−1. The output powers in both directions achieved at a cavity length of 2900 μm in the cw and pulsed regimes were 2.1 and 23 W, respectively.
Composite three-layer potassium and silver halide fibre for the mid-IR range
Authors: Butvina A.L. , Butvina L.N. , Okhrimchuk A.G.
Published: November 2019

We report for the first time the possibility of co-extrusion of silver and potassium halide crystals to produce double-clad polycrystalline IR fibres. This combination allows the disadvantages inherent in each of the crystals separately to be overcome. The resulting fibres have stable long-term transmission and can be used to transmit CO2 laser radiation. The loss in the fibre at a wavelength of 10.6 μm constitutes 0.75 dB m−1.
Propagation of megawatt subpicosecond light pulses with the minimum possible shape and spectrum distortion in an air- or argon-filled hollow-core revolver fibre
Authors: Gladyshev A.V. , Yatsenko Yu.P. , Kosolapov A.F. , Myasnikov D.V. , Bufetov I.A.
Published: November 2019

We have examined the feasibility of undistorted subpicosecond pulse transmission at peak powers of up to 100 MW and a wavelength of 1030 nm in a hollow-core revolver fibre having a core filled with atmospheric air or argon. A hollow-core revolver fibre has been fabricated which has a low-dispersion (β
2 ≈ – 0.25 ps2 km−1) transmission band in the spectral range of ytterbium and neodymium lasers. Conditions for the nonlinear (soliton) regime of megawatt picosecond pulse propagation over up to 1-km lengths of revolver fibre in atmospheric air and argon at pressures in the range 10−5 to 1 atm have been found theoretically. We have experimentally demonstrated transmission of pulses of 0.8-ps duration and up to ∼100-MW power over an ∼3-m length of revolver fibre with the minimum possible distortion of their shape and spectrum.
Sensory effects of fluorescent organic dyes
Authors: Traven Valerii F. , Cheptsov Dmitrii A.
Published: November 2019

Organic dyes are very promising substrates for modern sensing technologies. Their utility is based on the ‘push-pull’ polarization of a π-electron system, as well as their polyfunctionality. These properties make organic dyes capable of fluorescent sensory response to many analytes and provide different mechanisms of both fluorescence increase and fluorescence quenching. Specific organic reactions and structural transformations of fluorescent organic dyes are under consideration in this review. The data confirming the structures of the products of the related analytical reactions are discussed in more detail. Knowledge of the transformations that fluorescent organic dyes undergo in sensory effects can contribute to successful design of specific probes for novel sensory technologies.

The bibliography includes 365 references.
White clover incorporation at high nitrogen application levels: results from a 3-year study
Authors: Guy C. , Hennessy D. , Gilliland T. J. , Coughlan F. , McClearn B. , Dineen M. , McCarthy B.
Published: November 2019

Context
High nitrogen (N)-fertiliser application levels and high stocking rates have been shown to optimise herbage dry-matter (DM) production in grass-only systems. Conversely, swards including white clover (Trifolium repens L.) are commonly suited to production systems at low N-fertiliser application levels (<150 kg N/ha) and low stocking rates (fewer than two livestock units (LU) per hectare). Despite this, the use of N fertiliser on grass–clover swards has generally increased during the past few decades, particularly in more intensively managed swards under dairy farming. Increasing inorganic N decreases sward white clover content in grass–clover swards, and increasing stocking rate on grass–clover swards can result in damage to white clover plants. However, under high N-application levels, a high stocking rate can also potentially minimise the negative effects of increased grass growth on sward white clover content.

Aims
The objective of the present study was to investigate the persistency of white clover in an intensive animal-grazing system, under a high N-fertiliser application level (250 kg N/ha) and at a high stocking rate (2.75 LU per hectare) over a 3-year period (2014–2016).

Methods
The study was a 2 × 2 factorial design, consisting of two perennial ryegrass ploidies (diploid, tetraploid) and two white clover treatments (grass-only, grass–clover). Four sward treatments (diploid-only, tetraploid-only, diploid + clover, tetraploid + clover) were evaluated over a full grazing season at a system scale. Sward measurements were taken at each grazing occasion for 3 years.

Key results
Over the 3 years, grass–clover swards produced an additional 1468 kg DM/ha when compared with grass-only swards. Sward white clover content decreased by 17% over the three study years.

Conclusions
This decrease in sward white clover content led to a decrease in contribution to cumulative herbage DM production.

Implications
Although the present study showed that white clover inclusion can increase herbage DM production at high N-fertiliser application levels, in association with high stocking rates, the initial extra herbage DM production on grass–clover swards decreased each year. Further studies should be undertaken to investigate whether the decline in white clover persistence observed is progressive over a longer time period.
Use of reflexive interactive design to address challenges to New Zealand dairy farming
Authors: Romera Álvaro J. , Neal Mark , Bos Bram
Published: November 2019

The New Zealand dairy industry will undergo significant changes over the next decades, so as to meet sustainability challenges (environmentally, economically, socially and ethically). The objective of the current study was to tackle these challenges by attempting a radical re-design of the dairy system. The study took a structured approach called reflexive interactive design. The intention was to address complex trade-offs between competing goals, deliberately targeting structural system changes in the systems. Through a series of interviews and design workshops, two concepts were drafted. These concepts are intended to be used as vehicles to construct shared meanings, in conversation with farmers, policy makers, scientists, the public, and other influential actors. Two findings relevant for consideration in redesigning dairy systems were as follows: first, the sustainability issues the industry is facing are interconnected, so solutions to one issue have implications for the others; second, the boundaries of the system to be designed may need to go beyond the farm gate, to include other parts of the value chain, groups of farms and possibly interconnected land uses.
The clonal grass Leymus chinensis overcomes salt stress by over-compensatory growth of individual ramets
Authors: Zheng Congcong , Ma Huimin , Gao Yingzhi , Sun Hao , Yang Haijun , Baskin Carol C.
Published: November 2019

Soil salinisation and overgrazing are two important factors limiting plant growth in the Songnen Grassland, Northeast China. Leymus chinensis, a dominant rhizomatous grass, resists grazing and tolerates saline–alkali stress. However, its adaptive mechanisms to the dual effects of grazing and saline–alkali stress remain largely unknown. A two-factorial field experiment was conducted in two consecutive years in the natural L. chinensis community, combining the addition of mixed saline–alkali solution (NaCl:NaHCO3:Na2CO3 1:1:1, amount 559.13 g m–2 year–1) with clipping (removal of 60% of aboveground biomass, AGB). Saline–alkali addition significantly increased AGB and total biomass in the no clipping but not in the clipping treatment. Irrespective of clipping, ramet density was significantly decreased, and individual ramet biomass was significantly increased under salt stress. The significant increase in AGB was due to a high K+:Na+ ratio, high water-use efficiency, and an increase in leaf area index and net photosynthesis rate of individual ramets under salt–alkali stress. Clipping significantly decreased AGB and total biomass regardless of saline–alkali addition, possibly because of decreased sugar content of rhizomes. Saline–alkali and clipping had an interactive effect on AGB and total biomass of L. chinensis. The significant reduction in AGB and total biomass were mainly caused by reduced proline and water-soluble carbohydrate content under dual stress. A modified and simplified graphic model of the limiting resource model was proposed based on our results. Leymus chinensis can grow well under saline–alkali stress via ramet biomass compensation, in which the significant decrease in ramet density is compensated by the significant increase in individual ramet biomass. Ramet compensation and clonal integration were identified to be main mechanisms of herbivory and saline–alkali tolerance.
Variation in root morphology and P acquisition efficiency among Trifolium subterraneum genotypes
Authors: McLachlan Jonathan W. , Haling Rebecca E. , Simpson Richard J. , Li Xiaoxi , Flavel Richard J. , Guppy Chris N.
Published: November 2019

Trifolium subterraneum L. is widely grown in the phosphorus (P) deficient soils of southern Australia. However, this pasture legume has a high critical external P requirement and requires frequent applications of P fertiliser to achieve high productivity. Twenty-six genotypes of T. subterraneum were grown to determine: (i) differences in shoot growth and P acquisition under low-P supply; (ii) the root morphological traits important for P acquisition; and (iii) the feasibility of selection among genotypes for these root morphological traits. Micro-swards of each genotype were grown with a topsoil layer that was either moderately P-deficient or had P supplied in excess of the critical requirement for maximum yield; the subsoil layer was P-deficient. Yield and P content of shoots and roots were determined after 5 weeks’ growth, and root samples were assessed for diameter, length and root hair length. All genotypes were equally highly productive when excess P was supplied. However, relative shoot yield in the moderately P-deficient soil ranged from 38–71%. Total root length ranged from 63–129 m pot–1, and was correlated with total plant P uptake (R2 = 0.78, P < 0.001). Variation was also observed in average root diameter (0.29–0.36 mm) and root hair length (0.19–0.33 mm). These traits were combined with root length to calculate the total surface area of the root hair cylinder, which was also correlated with total plant P uptake (R2 = 0.69, P < 0.001). The results demonstrated that there was significant variation in P acquisition efficiency and shoot yield among genotypes of T. subterraneum when grown in P-deficient soil, and that root length was important for improved P uptake. The results indicate potential to identify superior genotypes that achieve improved P acquisition and higher shoot yields in low-P soil.
Microwave-assisted fabrication of slight-expanded graphite under normal temperature
Authors: Liu Zhen-Xue , Zhang Xiao-Wen , Zhang Wan-Jia , Wei Xiao-Xuan , Liang Peng
Published: November 2019

Different from traditional expanded graphite, novel slight-expanded graphite with only four times expansion was produced. The preparation method presented here includes an improved Hummers method to change the natural flake graphite to graphite oxide by using lower amounts of concentrated sulfuric acid and concentrated phosphoric acid. Then, the graphite oxide is expanded via microwave irradiation instead of temperature increase. Scanning electron microscope images and X-ray diffraction patterns show that the lamellar structure of natural graphite was changed to a complex, overlapped, curled-up structure in the slight-expanded graphite.
Understanding the attributes of the dual oasis effect in an arid region using remote sensing and observational data
Authors: Bie Qiang , Xie Yaowen , Wang Xiaoyun , Wei Baocheng , He Lei , Duan Hanming , Wang Ju
Published: November 2019

Investigating the attributes of the dual oasis effect and oasis–desert interactions is crucial for understanding the climatic and ecological effects of oases. In this study, oasis effect intensity (OEI) was used as an indicator to investigate the factors that contribute to the dual oasis effect. The oasis effect has two attributes: the surface oasis heating effect (OHE) occurred in winter, while the oasis cooling effect (OCE) occurred in the other three seasons, especially in summer. During the day, the OEI of the whole oasis was −12.8°C, −5.2°C, and −4.5°C in summer, spring, and autumn, respectively, which indicated a strong OCE; and OEI was 0.5°C in winter, which indicated a weaker OHE. In arid regions, the OCE dominated most of the time, but the OHE occurred in winter and cannot be ignored. In addition, through statistical analysis and energy balance analysis, high evapotranspiration of the oasis was the main factor leading to the occurrence of OCE in the summer, while low albedo to the occurrence of OHE in winter.
Field emission microscopy pattern of a single-crystal diamond needle under ultrafast laser illumination
Authors: Mammez M H , Borz M , Blum I , Moldovan S , Arnoldi L , Idlahcen S , Hideur A , Kleshch V I , Obraztsov A N , Vella A
Published: November 2019

We report herein on the spatial beam properties of a field emission electron source based on a single-crystal diamond needle illuminated by ultrashort light pulses. We show that the increasing of the laser intensity strongly modifies the emission pattern, leading to the emergence of a new emission region at high peak power. This region is situated on the opposite side of the diamond needle to the one irradiated by the laser. By spatially-resolved energy spectrometry, we prove that the electrons emitted from this region are governed by a multi-photon absorption process. The occurrence of this emission pattern can be explained by accounting for the inhomogeneous distribution of the optical field enhancement and the laser absorption induced by light diffraction within the nanometric needle. The numerical simulations performed on a real sub-wavelength tip confirm this localization of the optical field enhancement and reveal that the electrons trajectories match the spatial beam distribution evidenced experimentally. This work underlines the need to closely monitor the surface roughness of the field emitter as well as the laser illumination conditions to finely control its emission pattern.
Tunable multistability and nonuniform phases in a dimerized two-dimensional Rydberg lattice
Authors: Zhang Han-Xiao , Fan Chu-Hui , Cui Cui-Li , Wu Jin-Hui
Published: November 2019

We study the multistability of fixed points for a dimerized system of Rydberg atoms driven by two laser fields and trapped in a two-dimensional (2D) square lattice. For identical driving fields, the fixed points of this system exhibit stable uniform, unstable uniform, stable nonuniform, or oscillating nonuniform phases in the presence of a bistable region. For different driving fields, however, all (stable, unstable, or oscillating) phases become nonuniform instead, which then results in two islets isolated from the mainland of Rydberg excitation. We also show that a tristable region may stretch out from the (nonuniform) bistable region near the islets, indicating that a richer phase diagram can be attained by tuning the Rabi frequencies and/or detunings of the driving fields. Last but not least, the fixed points can adiabatically evolve from the islets to the mainland but can not inversely evolve from the mainland to the islets.
Rainfall and Wave Height Prediction in Semarang City Using Vector Autoregressive Neural Network (VAR-NN) Methods
Authors: Sugito  , Mustafid  , Safitri D , Ispriyanti D , Hakim A R , Yasin H
Published: November 2019

In the past few months in Semarang City, high rainfall and high waves give negative impact because the activities of fishermen to be stopped due to the waves of water. Another disadvantage is ROB flood. This is quite detrimental in addition to disrupting transportation and economic activities, but also causing damage to both government-owned assets and personal assets. This damage is caused by flood water which is mixed with sea water containing salt, so that it can cause corrosion. Vector of Autoregressive Neural Network (VAR-NN) is a development of the Autoregressive Vector (VAR) method using the Neural Network (NN) algorithm. The VAR method does not need to distinguish between endogenous and exogenous variables, its means that all variables used in the VAR model are used as endogenous variables. The VAR model can be used to explain and make predictions from endogenous variables from past data on these variables. VAR is developed using the Neural Network (NN) algorithm, where the basic principle of NN itself is an information processing algorithm that resembles the workings of the human brain, which uses a number of neurons to perform simple tasks. VAR-NN is often used in the economic, financial fields and believed to be able to make predictions of high rainfall and wave height. In this study using VAR-NN with FeedForward algorithm or called Backpropagatian. The results of rainfall prediction and wave height in Semarang city using this method have a Mean Square Error of 12,325 with the VAR-NN model (3, 2, 4).
Optimizing the traffic control system of Sultan Agung street Yogyakarta using fuzzy logic controller
Authors: Mualifah L N A , Abadi A M
Published: November 2019

The traffic control system is a system that functions to regulate and control traffic flow at crossroads, pedestrian crossings (zebra crossing) and other traffic flows. A good traffic control system is a system that is able to adjust the duration of the traffic lights with the density of traffic flow automatically. In big cities like Yogyakarta, traffic congestion is one of the most common problems. It is caused by the traffic lights that use a conventional regulation system. This study aims to discuss the establishment of a traffic light regulation system on Sultan Agung street and surrounding areas where there are nearby traffic lights and are interrelated with one another. Determining the duration of the green light is calculated using the fuzzy logic controller method with 3 input variables namely the number of cars, the number of motorcycles, and the length of the queue. The results of the traffic light regulation system using fuzzy logic controllers are more effective than conventional system settings. It is because the system is able to adjust the duration of the traffic lights with traffic conditions at that time, so the duration of traffic light is varied for each traffic conditions.
The Improvement Technique in Assessing Teaching Skills using Fuzzy Weighted Grading Method
Authors: Andayani S
Published: November 2019

The assessment of education is the process of providing the decision on the performance and quality of student achievement. Many cases indicate that the educational assessment involves many criteria of uncertain value, and therefore fuzzy assessment studies have grown rapidly in recent years. In this paper, a method is proposed to improve the assessment of the basic teaching skills of prospective teachers in a Micro-teaching course by using a fuzzy grading system. This method is also based on group decision-making (GDM) because it involves several decision makers who give preferences in the assessment process and negotiate to determine the criteria and sub-criteria for the assessment. The result of the method is a fuzzy value which is represented by a letter grade for the Micro-teaching course and letter grade for each of the basic teaching skills. By using this method, students may have the same final grade, but their mastering of teaching skills is very different.
An Analysis of Errors in Solving Limits of Algebraic Function
Authors: Nurhayati Rosnida , Retnowati Endah
Published: November 2019

By knowing types of mistakes made by students when solving mathematics problems, teacher can choose right learning strategy to avoid similar errors. This study aims to identify students’ errors in solving problems on limits of algebraic function. A total of 30 students in Yogyakarta vocational school who have studied concept of limits algebraic function, were asked to complete six questions without looking at the book in 45 minutes. Documents on student work were corrected by three mathematics teachers and identified the type of error that appeared. The results of the study are categorized into two types of errors: (1) procedural errors, including: errors not writing lim appropriately during executing limits, errors in substituting values into variables, errors not simplifying the final results, or no attempts; (2) conceptual error, including: errors in clearing fractions, errors in factoring, errors in rationalisation.
Increasing HOTS and student belief towards mathematics through learning with a roleplaying method
Authors: Sumantri C M S , Widjajanti D B
Published: November 2019

Belief in mathematics attitude of students towards mathematics, where students can give a positive or negative response to mathematics learning activities. Students are given math problems and when completing them, they will think first, then when finishing them, students are expected to be sure of the answers and the concepts they use are correct. When students experience difficulties in solving problems, negative beliefs appear in students because they feel unsure of the right answer. To help students so that confidence in mathematics (belief in math)becomes better, it is necessary to have an interesting learning method for students, namedrole-playing.The methodof role-playingis a learning method that prioritizes the role of students in the classroom, the teacher just gives the material without giving an explanation, and the rest of the students will deliver the material in a different way so that other students understand. Submission of different material uses a role-playing orrole-playing game, where students will play in a social environment and deliver material through previous roles compiled by the teacher using ahigh order thinking skill (HOTS) system.So, students are free to deliver material in accordance with what they understand and can be connected in a coherent way.
Djalaluddin Gorontalo Airport Passenger Data Forecasting with Holt’s-Winters’ Exponential Smoothing Multiplicative Event-Based Method
Authors: Djakaria Ismail
Published: November 2019

An appropriate time series model for predicting passenger data of Djalaluddin Gorontalo Airport, the interval between 2003 - 2017 with the multiplicative of Holt’s-Winters’ exponential smoothing as

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, so the smoothing parameter used are α = β = γ = 0.2. After several treatments, the mean square deviation (MSD) is 3287241 for arrival passenger data and MSD is 2490279 for passenger departure data with a seasonal length of 12 by do not event-based. The next, the MSD is 1334585 for arrival passenger data and MSD is 1433867 for passenger departure data with a seasonal length of 12 by Eid al-Fitr event-based, the MSD is 1259600 for arrival passenger data and MSD is 1252548 for passenger departure data with a seasonal length of 12 by Eid al-Adha event-based.
Comparison of Modelling Tasks in Indonesian and Singaporean Mathematics Textbooks
Authors: Syam S S , Wijaya A , Retnawati H
Published: November 2019

The ability of students to apply mathematics has been regarded as an important goal of mathematics education in many countries, including Indonesia and Singapore. One of such abilities is the competence of mathematical modelling. Presenting students with mathematical modelling task is one of the efforts to improve their competence of mathematical modelling. This study aims to describe the characteristics of mathematical modelling task in Indonesian and Singaporean mathematics textbooks. This study used a qualitative approach with content analysis technique. The books analyzed in this study were an Indonesian mathematics textbook published by the government and a Singaporean mathematics textbook: Discovering Mathematics. Classification category for the modelling tasks is adapted from the classification made by Katja Maaß (2010). The results of analysis showed that there is no significant difference between Indonesian and Singaporean mathematics textbooks. Indonesian mathematics textbook contains contexts that are still small as well as Singaporean mathematics textbook. Therefore, more comprehensive research is needed with regard to curriculum content and learning strategies in Indonesia and Singapore.
An analysis mathematical problem solving and mathematical critical thinking skills of junior high school students
Authors: Susanti E , Hartono
Published: November 2019

This article describes mathematical problem solving and critical thinking skills and examines the relationship between junior high school students’ problem solving skills and critical thinking skills in learning mathematics. The research samples consisted of thirty-six students at the age of 13 to 14 having mathematical abilities on above average who were selected through purposive random sampling technique from one public junior high school of Yogyakarta. Data were obtained from tests of problem solving skills and critical thinking skills. Both instruments are essay questions. Quantitative analysis is used to determine level of problem solving skills, level of critical thinking skills, and relationship between them. The results revealed that the average of students’ problem solving skills and mathematical critical thinking skills was in the medium criteria where critical thinking skills were slightly higher than problem solving skills. Besides, the relationship between them belonged to medium category.
An Analysis of Student Difficulties in Solving the Word Problem
Authors: Habibullah  , Hartono
Published: November 2019

This research is a qualitative descriptive research that aims to describe the types and factors of difficulty in solving mathematics problems in the form of word problems. The research subjects were 22 students who were selected by random sampling technique from one of the junior high schools in Indragiri Hilir. The data was collected through diagnostic tests and interviews conducted openly but not structured. In analyzing the students’ difficulties, the revised Bloom’s Taxonomy theory was used to find the difficulties in factual, conceptual, procedural, and metacognitive knowledge. The results of research showed that 14.77% of students had difficulties in factual knowledge, 17.05% of students had difficulties in conceptual knowledge, 45.46% of students had difficulties in procedural knowledge, and 53.41% of students had difficulties in metacognitive knowledge. The factors that cause difficulties were experienced by students, such as: their sense in lack of time, carelessness, anxiety, giving up easily, and being hasty in doing the given problem.
Expanding hypothetical learning trajectory in mathematics instructional
Authors: Ulfa Charina , Wijaya Ariyadi
Published: November 2019

The purpose of this article is to present a description of Hypothetical Learning Trajectory (HLT) which can be used as an instrument in mathematics learning activities in the classroom. More than 25 years, HLT has been introduced and developed in every learning especially mathematics learning. An HLT is developed based on the learning objectives, characteristics of students and the material to be taught. In HLT contains three important things that are: (1) learning objectives, (2) learning activities used in building students’ knowledge, and (3) allegations of the learning activities process. This article uses a literature review of previous theories. HLT can be developed with various learning methods that are adjusted to the characteristics of students and the material to be taught. However, this article only discusses important things that need to be considered in the development of HLT in mathematics learning. So that it is obtained that HLT can help students in building knowledge in a reflective manner.
Identification of student’s metacognition level in solving modeling mathematical problem
Authors: Thufaila Dewi , Sugiman
Published: November 2019

This study aims at identifying the students’ metacognition level in solving mathematical modeling problem. Subjects of this study is eight seventh grade students in junior high school which selected based on their latest mathematics test exam score and communication ability test. The results of this study are obtained by using mathematical modeling problem test and interview. The results of this study are that students in the tacit use level is not know the reason why did they use the certain ways that they did to solve the problem, most of the time they just use ‘try and error’ method. Students in the aware use already know the reason why they use a certain ways to solve a certain problem. Students in the strategic use are capable on create their own strategy before solving the problem. Students in reflective use are not only building a plan before solving the problem, but also reflecting and evaluating during and after they obtain the result of the problem.
Student-teacher’s perception of mathematical representation in mathematics learning
Authors: Novianti M , Retnawati H
Published: November 2019

This research aims to know student-teacher’s perception of mathematical representation in mathematical learning. This research is a qualitative research. The subject of this research are 12 student-teacher. Data collection technique are carried out through interview. Data analyze using Bogdan and Biklen. Data analysis includes steps to collected data, reducted data, categorizing the data and made conclusions. The result show that the twelve subjects can describe the definition of mathematical representation. The subjects considered mathematical representation is important in mathematical learning, which is for: 1) Understanding the concepts, 2) Problem Solving, 3) Construction the concepts and 4) Communication. The subjects considered that it is difficult to develop mathematical representation in mathematical learning.
Experimental investigation on the effect of geometry on cryogenic transfer line chilldown
Authors: Mohammed Jesna , Rasheed Rizwan , Junaid Faraz P , Roy K E Reby
Published: November 2019

In order to analyze the effect of geometry on cryogenic chilldown, experiments were performed on straight, one twisted and twin twisted copper tubes using liquid nitrogen. Data presented in this paper is for the experiments conducted under terrestrial gravity conditions at supply pressures of 1.2 bar and 1.3 bar. Test sections considered were copper tubes (7.9375 mm OD, 0.8128 thick) of straight, one twisted and twin twisted geometry traversing a distance of 220mm under Polyurethane foam insulation. Pressure measurements at test section inlet and outlet was monitored using transducers. Temperature measurement at four equidistant sections along the length were tracked in real-time using a data acquisition system. Temperature and pressure profiles were obtained. The results of the experiment indicated that, for a given mass flux, the transition during chilldown occurs earlier in one twisted transfer lines compared to straight and twin twisted tubes. This indicates the earlier occurrence of film boiling for the one twisted channels. Thereby, changing the transfer line geometry from straight tubes to one twisted sections, the chilldown time can be reduced to a considerable extend further resulting in reduction of cryogen consumption during the initial stages of transfer process.
Helmholtz resonator based metamaterials for sound manipulation
Authors: Mahesh K , Mini R S
Published: November 2019

Metamaterials are tailored artificial structures that received wide attention now a days due to their extraordinary properties like negative density, negative bulk modulus, negative permeability, negative refractive index etc.. Shape, geometry, size, orientation and arrangement of the basic units in metamaterials give them their smart properties capable of manipulating electromagnetic and acoustic waves by blocking, absorbing, enhancing, or bending waves to achieve benefits that go beyond what is possible with conventional materials. Acoustic metamaterial with Helmholtz resonators (HRs) is considered in this study. The behaviour of acoustic waves in the presence of array of Helmholtz resonators in series and parallel arrangement is studied numerically using finite element method. Series arrangement of Helmholtz resonators resulted in the extraordinary transmission of acoustic waves of certain frequencies and parallel arrangement resulted in the focusing of sound.
Influence of nano (h –BN) cutting fluid on machinability of Inconel 625
Authors: Singh Pariniti , Padhy Chinmaya P.
Published: November 2019

Inconel 625 has got wide applications across industries (aerospace, petrochemical etc.) in various machining operations. During machining, large amount of heat is generated due to the friction, lowering the tool life and adding to various wear mechanism. This is sorted by conventional cooling/lubrication, but, with its harmful effect on environment and human health, it’s imperative to pursue other cleaner, greener though efficient alternatives. In this regard, MQL assisted with h-BN nano fluid is an effective option. Hexagonal Boron Nitride (h-BN) having unique structure and composition displays advanced mechanical properties which enhances its versatility in applications. To investigate effectiveness of nano (h –BN) cutting fluid on machinability, first h-BN nanofluid was prepared and characterized for its mechanical properties for nanoparticle concentrations (0.05,0.1 % Vol.). Further, the machining performance and sustainability associated with turning of Inconel-625 under different lubricating conditions viz. dry, wet, MQL with conventional cutting fluid and MQL with (h-BN) nano cutting fluid (NCF) are investigated for machining characteristics. Results showed that MQL integrated with h-BN nano cutting fluid is an effective and sustainable option.
Comparison of Mechanical Properties of Zn-27A1 Alloy Using Various Casting Techniques
Authors: Sreejith J , Nishad K , Krishnadas M , Krishnaprasad C N , Muralidharan Mamatha , Krishnaprasad V , Rajesh Menon B
Published: November 2019

Zinc-aluminium alloys are cost effective substitute for wide range of applications in the industrial purpose mainly as bearing materials. Zn- 27 Al is the material selected due to its good mechanical and tribological properties. Casting is one of the methods which can be used to fabricate the alloys. Sand casting and stir casting are used to develop Zn- 27 Al alloy. Both mechanical and wear properties were studied. Hardness, tensile strength and impact strength is highest for the stir casted alloy when compared to sand casted Zn-27 Al.. The composition of the prepared alloys justifies the better properties of stir casted alloy and the compositions are analysed by Energy Dispersive X-Ray (EDX) analysis.
Measurement science in methodological instruction of Ph.D. students of technoscience
Authors: Morawski Roman Z
Published: November 2019

Technoscience is a result of integration of technology with empirical sciences, including not only physical sciences, but also life sciences, social sciences and cognitive sciences. The development of technoscience is unthinkable without measurement and mathematical modelling, being two interrelated operations used for acquisition and representation of knowledge. Measurement fundamentals must, therefore, belong to the core of methodological instruction of Ph.D. students of technoscience. This keynote speech will provide an outline of a graduate course on methodological aspects of technoscientific research, whose programme includes conceptual analysis of the dialectical relationship between measurement and mathematical modelling, of the role of measurement in scientific explanation, of the role of measurement in the context of discovery and in the context of justification, as well as of the role of measurement in mitigating uncertainty of scientific knowledge.
Probabilistic measurement modelling may overcome the opposition between the Bayesian and the frequentistic views
Authors: Battista Rossi Giovanni , Crenna Francesco
Published: November 2019

The probabilistic modelling of measurement systems is discussed, in regards to uncertainty evaluation and different models representing the same real system from different standpoints are compared. We suggest that proper probabilistic modelling directly yields evaluation of measurement uncertainty, without making any commitment to specific philosophical schools, such as the frequentistic and the Bayesian ones. We suggest that this model-based approach may have advantages in education and in the development of recommended practices in measurement.
Dissolved oxygen and pH detection system based on the fluorescence characteristics of coumarin-modified CdSe quantum dots
Authors: Zheng Chao , Tao Wei , Liu Quan , Lv Na , Wang Kan , Zhao Hui
Published: November 2019

In the field of biomedicine, the pH and dissolved oxygen (DO) content of the cell metabolism fluid can reflect the health of the cell and provide an auxiliary reference for the early detection of cancer. Based on the preliminary research results of the same group, a dual-parameter synchronous detection system for cell metabolic fluid was established. The system is based on the fluorescence characteristics of 7-Amino-4-methylcoumarin-modified CdSe quantum dots. Both of pH and DO are solved by the voltage signal of the photodetection module. Firstly, the characteristics of 7-Amino-4-methylcoumarin-modified CdSe quantum dots were introduced. Then the dual-parameter detection method was briefly proposed. Next, the hardware components and software functions of the system were introduced. Finally, the detection algorithm was proposed and the solution model was built according to the calibration experiment. The verification experiment showed that the sensitivity for detecting pH was 0.05 and the accuracy was 0.07. The sensitivity for detecting DO was 0.04 mg/L, and the accuracy was 0.07 mg/L. As the prototype machine, the system can basically realize the dual-parameter detection of the cell metabolism liquid with high accuracy, fast speed and small loss of the original liquid.
Conformity assessment of glare in buildings considering the uncertainty of the parameter UGRL
Authors: Ribeiro A S , Martins L , Santos A
Published: November 2019

The evaluation of discomfort related to glare is a common need in buildings, requiring conformity assessment defined in the standard EN 12464-1:2011, using the parameter UGRL
index and a related scale with threshold levels associated with perceptible behaviour transitions. The scale is defined for a dimensionless parameter related to the degree of psychological (discomfort) glare of an electric lighting installation in an indoor space. The aim of this paper is to provide a comprehensive understanding of the role of the UGRL
uncertainty in the conformity assessment procedure, being a critical quantity used in the definition of a decision rule under the new edition of the ISO / IEC 17025 standard. The impact of the uncertainty of the UGRL
quantity is shown using examples of decision rules in measurements near the transition limits of the scale.
Can there be one meaning of “measurement” across the sciences?
Authors: Mari Luca , Maul Andrew , Wilson Mark
Published: November 2019

The International Vocabulary of Metrology (VIM) gives the following definition of ‘measurement’: “process of experimentally obtaining one or more quantity values that can reasonably be attributed to a quantity”. In pursuit of a common understanding of measurement, we explore this condition of reasonableness across the sciences, asking in particular whether there are common features of the structure of measurements in different fields of study that could meet this criterion. We propose that a general sufficient condition for measurement is that it is an experimental process of evaluation of empirical properties that produces explicitly justifiable information, which, we argue, is consistent with characterizations of science and epistemology more generally.
Addressing traceability in social measurement: establishing a common metric for dependence
Authors: Salzberger T , Cano S , Abetz-Webb L , Afolalu E , Chrea C , Weitkunat R , Fagerström K , Rose J
Published: November 2019

Measurement in the social sciences is characterised by a multitude of incompatible paradigms, most of which fail to adhere to fundamental principles of measurement explicated in metrology. This has led to a fragmentation of instruments that are hard to interpret and lack a common reference. Rasch measurement theory, the metrological framework of the Rasch model, combined with strong substantive theories of the measurand, has the potential to advance measurement in the social sciences significantly. The Rasch model establishes a reference standard with a common unit of measurement against which different instruments can be calibrated ensuring traceability in social measurement. Uncertainty in the calibration process is addressed by a standard error of measurement for a specific estimate taking into account that precision varies over the continuum of the measurand. A strong substantive theory of the measurand allows for concrete predictions that can be tested empirically with positive evidence supporting accuracy. We exemplify the potential of the Rasch model by developing the ABOUT-Dependence, a new instrument for the measurement of dependence on tobacco- and nicotine-containing products (TNP). The instrument provides comparable measurements of dependence on different TNPs as well as dependence on multiple TNPs used concurrently. A co-calibration of the new instrument and existing, product-specific instruments allows for a conversion of scores of existing instruments into scores on the new instrument, and vice versa, via the established equal-unit reference scale. The score comparability adds to traceability in the measurement of dependence, is likely to facilitate the acceptance of the new instrument, and helps avoid a discontinuity in the research of dependence.