bluuebunny/crossref_metadata_2025 huggingface dataset:
Immersed boundary–simplified thermal lattice Boltzmann method for incompressible thermal flows
Authors: Chen Z. , Shu C. , Yang L. M. , Zhao X. , Liu N. Y.
Published: January 2020

An immersed boundary–simplified lattice Boltzmann method (IB-STLBM) is proposed in this paper for the simulation of incompressible thermal flows with immersed objects. The fractional step technique is adopted to resolve the problem in two successive steps. In the predictor step, the simplified thermal lattice Boltzmann method (STLBM) is utilized to resolve the intermediate flow variables without considering the immersed objects. The STLBM is advantageous over the conventional thermal lattice Boltzmann method (TLBM) in memory cost, boundary treatment, and numerical stability. In the corrector step, the boundary condition-enforced immersed boundary method (IBM) is used to give correction values of velocity and temperature for accurate interpretation of the Dirichlet boundary conditions on the surface of the immersed objects. Based on the present IBM, some novel strategies can be applied in the evaluation of hydrodynamic forces or thermal parameters of the immersed objects. Five numerical examples are presented for comprehensive validation of the accuracy and robustness of IB-STLBM in various two- and three-dimensional thermal flow problems.
Memristive phase switching in two-dimensional 1T′-VSe2 crystals
Authors: Sun Yue , Dai Tian , He Zhihao , Zhou Wenqi , Hu Ping , Li Shuwei , Wu Shuxiang
Published: January 2020

Charge density waves (CDWs) have received extensive attention due to their unique physical properties and potential applications in oscillators and memory devices. Transition metal dichalcogenides are typical prototypes for studying CDWs. 1T′-VSe2 films grown by molecular beam epitaxy exhibited a sudden change in resistance at about 270 K, corresponding to a critical temperature of transition from the normal phase to the CDW phase. In addition, the phase transition can be modulated by voltage and the corresponding resistance states are controllable due to local Joule heating, which could be applied to the memory device. Temperature-dependent Raman characterization showed a significant change in the Raman pattern of the 1T′-VSe2 films around 270 K, further confirming the CDW phase transition observed by electrical transport measurements. The results are important not only for understanding the microscopic physics and electrical control of CDW phases, but also probably play an important role in the future applications of these CDW materials.
The modeling of grain surface chemistry
Authors: Chen Long-fei , Li Fang-fang , Chang Qiang
Published: January 2020

Astrochemistry has made great progress in recent years. Especially the grain surface chemistry played important roles in the explanation of the formation of the interstellar molecules. In this review, we will discuss the progress, including the different numerical methods to simulate the ice mantles in the astrochemical models. We will also introduce the laboratory astrochemical experimental results, and their contributions to the grain surface chemistry in the review.
Maxwell Frank Cooper Day 1915–2017
Authors: Robin Libby , Day Jon C.
Published: January 2020

Max Day (1915–2017) entomologist, scientific diplomat and conservationist, was a national scientific leader across the twentieth century, a time that spanned the rise of the idea of the environment and of concern about ecological limits. He was a pioneer in Australia of integrated, cross-disciplinary science and an important advocate of evidence-based policy-making. His fundamental disciplinary work in entomology, virology, ecology and forestry focused on nationally significant problems and their international context.
The importance of transient social dynamics for restoring ecosystems beyond ecological tipping points
Authors: Martin Romina , Schlüter Maja , Blenckner Thorsten
Published: January 2020

Significance

Managing regime shifts is often associated with “turning back from the brink” assuming that once a system has transgressed a tipping point, it moves unavoidably toward the undesired state. We show that a regime shift is rather a slippery slope that can be managed and even reversed when transient dynamics and time lags in the coupled social-ecological system are taken into account. We constructed an empirically based simulation model that includes the combined effect from nonlinear ecological dynamics and human adaptation. Delayed policy response and slow implementation introduce time lags that can strongly affect lake restoration time. Our model demonstrates how time lags in municipal policy making can be compensated for by individual action mediated through social pressure.
Pressure sensing through Piezo channels controls whether cells migrate with blebs or pseudopods
Authors: Srivastava Nishit , Traynor David , Piel Matthieu , Kabla Alexandre J. , Kay Robert R.
Published: January 2020

Significance

Cells migrating within the body perform vital functions in development and for defense and repair of tissues. In this dense environment, cells encounter mechanical forces and constraints not experienced when moving under buffer, and, accordingly, many change how they move. We find that gentle squashing, which mimics mechanical resistance, causes cells to move using blebs—a form of projection driven by fluid pressure—rather than pseudopods. This behavior depends on the Piezo stretch-operated ion channel in the cell membrane and calcium fluxes into the cell. Piezo is highly conserved and is required for light touch sensation; this work extends its functions into migrating cells.
Structural elements regulating the photochromicity in a cyanobacteriochrome
Authors: Xu Xiuling , Höppner Astrid , Wiebeler Christian , Zhao Kai-Hong , Schapiro Igor , Gärtner Wolfgang
Published: January 2020

The three-dimensional (3D) crystal structures of the GAF3 domain of cyanobacteriochrome Slr1393 (
Synechocystis
PCC6803) carrying a phycocyanobilin chromophore could be solved in both 15-
Z
dark-adapted state, Pr, λ
max
= 649 nm, and 15-
E
photoproduct, Pg, λ
max
= 536 nm (resolution, 1.6 and 1.86 Å, respectively). The structural data allowed identifying the large spectral shift of the Pr-to-Pg conversion as resulting from an out-of-plane rotation of the chromophore’s peripheral rings and an outward movement of a short helix formed from a formerly unstructured loop. In addition, a third structure (2.1-Å resolution) starting from the photoproduct crystals allowed identification of elements that regulate the absorption maxima. In this peculiar form, generated during X-ray exposition, protein and chromophore conformation still resemble the photoproduct state, except for the D-ring already in 15-
Z
configuration and tilted out of plane akin the dark state. Due to its formation from the photoproduct, it might be considered an early conformational change initiating the parental state-recovering photocycle. The high quality and the distinct features of the three forms allowed for applying quantum-chemical calculations in the framework of multiscale modeling to rationalize the absorption maxima changes. A systematic analysis of the PCB chromophore in the presence and absence of the protein environment showed that the direct electrostatic effect is negligible on the spectral tuning. However, the protein forces the outer pyrrole rings of the chromophore to deviate from coplanarity, which is identified as the dominating factor for the color regulation.
Nucleosomal proofreading of activator–promoter interactions
Authors: Shelansky Robert , Boeger Hinrich
Published: January 2020

Significance

We show that kinetic proofreading of activator–promoter interactions solves a fundamental problem in gene regulation: that the specificity of eukaryotic activators cannot be explained by activator–DNA recognition alone. In light of our theory, multiple observations point to a role of nucleosomes in the kinetic proofreading of activator-DNA recognition. Our theory explains, among other findings, why transcription may occur in stochastic bursts.
Decoding of the other’s focus of attention by a temporal cortex module
Authors: Ramezanpour Hamidreza , Thier Peter
Published: January 2020

Faces attract the observer’s attention toward objects and locations of interest for the other, thereby allowing the two agents to establish joint attention. Previous work has delineated a network of cortical “patches” in the macaque cortex, processing faces, eventually also extracting information on the other’s gaze direction. Yet, the neural mechanism that links information on gaze direction, guiding the observer’s attention to the relevant object, has remained elusive. Here we present electrophysiological evidence for the existence of a distinct “gaze-following patch” (GFP) with neurons that establish this linkage in a highly flexible manner. The other’s gaze and the object, singled out by the gaze, are linked only if this linkage is pertinent within the prevailing social context. The properties of these neurons establish the GFP as a key switch in controlling social interactions based on the other’s gaze.
Molecular mechanism for the recognition of sequence-divergent CIF peptides by the plant receptor kinases GSO1/SGN3 and GSO2
Authors: Okuda Satohiro , Fujita Satoshi , Moretti Andrea , Hohmann Ulrich , Doblas Verónica G. , Ma Yan , Pfister Alexandre , Brandt Benjamin , Geldner Niko , Hothorn Michael
Published: January 2020

Plants use leucine-rich repeat receptor kinases (LRR-RKs) to sense sequence diverse peptide hormones at the cell surface. A 3.0-Å crystal structure of the LRR-RK GSO1/SGN3 regulating Casparian strip formation in the endodermis reveals a large spiral-shaped ectodomain. The domain provides a binding platform for 21 amino acid CIF peptide ligands, which are tyrosine sulfated by the tyrosylprotein sulfotransferase TPST/SGN2. GSO1/SGN3 harbors a binding pocket for sulfotyrosine and makes extended backbone interactions with CIF2. Quantitative biochemical comparisons reveal that GSO1/SGN3–CIF2 represents one of the strongest receptor–ligand pairs known in plants. Multiple missense mutations are required to block CIF2 binding in vitro and GSO1/SGN3 function in vivo. Using structure-guided sequence analysis we uncover previously uncharacterized CIF peptides conserved among higher plants. Quantitative binding assays with known and novel CIFs suggest that the homologous LRR-RKs GSO1/SGN3 and GSO2 have evolved unique peptide binding properties to control different developmental processes. A quantitative biochemical interaction screen, a CIF peptide antagonist and genetic analyses together implicate SERK proteins as essential coreceptor kinases required for GSO1/SGN3 and GSO2 receptor activation. Our work provides a mechanistic framework for the recognition of sequence-divergent peptide hormones in plants.
A combined rheometry and imaging study of viscosity reduction in bacterial suspensions
Authors: Martinez Vincent A. , Clément Eric , Arlt Jochen , Douarche Carine , Dawson Angela , Schwarz-Linek Jana , Creppy Adama K. , Škultéty Viktor , Morozov Alexander N. , Auradou Harold , Poon Wilson C. K.
Published: January 2020

Suspending self-propelled “pushers” in a liquid lowers its viscosity. We study how this phenomenon depends on system size in bacterial suspensions using bulk rheometry and particle-tracking rheoimaging. Above the critical bacterial volume fraction needed to decrease the viscosity to zero,

ϕ

c

≈
0.75
%

, large-scale collective motion emerges in the quiescent state, and the flow becomes nonlinear. We confirm a theoretical prediction that such instability should be suppressed by confinement. Our results also show that a recent application of active liquid-crystal theory to such systems is untenable.
Widespread remodeling of proteome solubility in response to different protein homeostasis stresses
Authors: Sui Xiaojing , Pires Douglas E. V. , Ormsby Angelique R. , Cox Dezerae , Nie Shuai , Vecchi Giulia , Vendruscolo Michele , Ascher David B. , Reid Gavin E. , Hatters Danny M.
Published: January 2020

The accumulation of protein deposits in neurodegenerative diseases has been hypothesized to depend on a metastable subproteome vulnerable to aggregation. To investigate this phenomenon and the mechanisms that regulate it, we measured the solubility of the proteome in the mouse Neuro2a cell line under six different protein homeostasis stresses: 1) Huntington’s disease proteotoxicity, 2) Hsp70, 3) Hsp90, 4) proteasome, 5) endoplasmic reticulum (ER)-mediated folding inhibition, and 6) oxidative stress. Overall, we found that about one-fifth of the proteome changed solubility with almost all of the increases in insolubility were counteracted by increases in solubility of other proteins. Each stress directed a highly specific pattern of change, which reflected the remodeling of protein complexes involved in adaptation to perturbation, most notably, stress granule (SG) proteins, which responded differently to different stresses. These results indicate that the protein homeostasis system is organized in a modular manner and aggregation patterns were not correlated with protein folding stability (ΔG). Instead, distinct cellular mechanisms regulate assembly patterns of multiple classes of protein complexes under different stress conditions.
Insect herbivory antagonizes leaf cooling responses to elevated temperature in tomato
Authors: Havko Nathan E. , Das Michael R. , McClain Alan M. , Kapali George , Sharkey Thomas D. , Howe Gregg A.
Published: January 2020

Significance

Crop damage by insect pests is predicted to increase as rising surface temperatures accelerate insect metabolism, population size, and range expansion. The plant defense hormone jasmonate promotes resistance to diverse herbivores, but how this wound signal impacts the plant’s ability to cope with a combination of herbivory and elevated temperature remains unknown. Here, we show that heat shock proteins contribute to enhanced jasmonate responses in tomato plants subjected to simulated heat waves. Herbivore-induced jasmonate signaling at elevated temperature, however, blocked stomatal opening and leaf hyponasty, leading to leaf overheating, reduced photosynthesis, and growth inhibition. Our results show how signal conflict between biotic and abiotic stress may exaggerate crop losses under warming conditions that accelerate herbivory, potentially jeopardizing food security.
Single-cell RNA sequencing of
Trypanosoma brucei
from tsetse salivary glands unveils metacyclogenesis and identifies potential transmission blocking antigens
Authors: Vigneron Aurélien , O’Neill Michelle B. , Weiss Brian L. , Savage Amy F. , Campbell Olivia C. , Kamhawi Shaden , Valenzuela Jesus G. , Aksoy Serap
Published: January 2020

Tsetse-transmitted African trypanosomes must develop into mammalian-infectious metacyclic cells in the fly’s salivary glands (SGs) before transmission to a new host. The molecular mechanisms that underlie this developmental process, known as metacyclogenesis, are poorly understood. Blocking the few metacyclic parasites deposited in saliva from further development in the mammal could prevent disease. To obtain an in-depth perspective of metacyclogenesis, we performed single-cell RNA sequencing (scRNA-seq) from a pool of 2,045 parasites collected from infected tsetse SGs. Our data revealed three major cell clusters that represent the epimastigote, and pre- and mature metacyclic trypanosome developmental stages. Individual cell level data also confirm that the metacyclic pool is diverse, and that each parasite expresses only one of the unique metacyclic variant surface glycoprotein (mVSG) coat protein transcripts identified. Further clustering of cells revealed a dynamic transcriptomic and metabolic landscape reflective of a developmental program leading to infectious metacyclic forms preadapted to survive in the mammalian host environment. We describe the expression profile of proteins that regulate gene expression and that potentially play a role in metacyclogenesis. We also report on a family of nonvariant surface proteins (Fam10) and demonstrate surface localization of one member (named SGM1.7) on mature metacyclic parasites. Vaccination of mice with recombinant SGM1.7 reduced parasitemia early in the infection. Future studies are warranted to investigate Fam10 family proteins as potential trypanosome transmission blocking vaccine antigens. Our experimental approach is translationally relevant for developing strategies to prevent other insect saliva-transmitted parasites from infecting and causing disease in mammalian hosts.
Acrosin is essential for sperm penetration through the zona pellucida in hamsters
Authors: Hirose Michiko , Honda Arata , Fulka Helena , Tamura-Nakano Miwa , Matoba Shogo , Tomishima Toshiko , Mochida Keiji , Hasegawa Ayumi , Nagashima Kiyoshi , Inoue Kimiko , Ohtsuka Masato , Baba Tadashi , Yanagimachi Ryuzo , Ogura Atsuo
Published: January 2020

Significance

Mammalian oocytes are surrounded by the zona pellucida, a glycoprotein coat that protects the oocyte and embryo from mechanical damage during their preimplantation development within the oviduct. Fertilizing spermatozoa must penetrate the zona, but we do not know the exact mechanisms underlying this process. Sperm proteases were thought to work as zona lysins, but gene-knockout studies in mice did not support this assumption. In this study, we generated hamsters without acrosin, the major acrosomal protease, to examine its role in both in vivo and in vitro fertilization. Surprisingly, mutant male hamsters were completely infertile because their spermatozoa were unable to penetrate the zona. We thus demonstrated that, at least in hamsters, acrosin is essential for sperm penetration through the zona.
African climate response to orbital and glacial forcing in 140,000-y simulation with implications for early modern human environments
Authors: Kutzbach John E. , Guan Jian , He Feng , Cohen Andrew S. , Orland Ian J. , Chen Guangshan
Published: January 2020

A climate/vegetation model simulates episodic wetter and drier periods at the 21,000-y precession period in eastern North Africa, the Arabian Peninsula, and the Levant over the past 140,000 y. Large orbitally forced wet/dry extremes occur during interglacial time, ∼130 to 80 ka, and conditions between these two extremes prevail during glacial time, ∼70 to 15 ka. Orbital precession causes high seasonality in Northern Hemisphere (NH) insolation at ∼125, 105, and 83 ka, with stronger and northward extended summer monsoon rains in North Africa and the Arabian Peninsula and increased winter rains in the Mediterranean Basin. The combined effects of these two seasonally distinct rainfall regimes increase vegetation and narrow the width of the Saharan–Arabian desert and semidesert zones. During the opposite phase of the precession cycle (∼115, 95, and 73 ka), NH seasonality is low, and decreased summer insolation and increased winter insolation cause monsoon and storm track rains to decrease and the width of the desert zone to increase. During glacial time (∼70 to 15 ka), forcing from large ice sheets and lowered greenhouse gas concentrations combine to increase winter Mediterranean storm track precipitation; the southward retreat of the northern limit of summer monsoon rains is relatively small, thereby limiting the expansion of deserts. The lowered greenhouse gas concentrations cause the near-equatorial zone to cool and reduce convection, causing drier climate with reduced forest cover. At most locations and times, the simulations agree with environmental observations. These changing regional patterns of climate/vegetation could have influenced the dispersal of early humans through expansions and contractions of well-watered corridors.
Interaction potentials for modelling GaN precipitation and solid state polymorphism
Authors: Wonglakhon Tanakorn , Zahn Dirk
Published: January 2020

We outline a molecular mechanics model for the interaction of gallium and nitride ions ranging from small complexes to nanoparticles and bulk crystals. While the current GaN force fields allow the modelling of either bulk crystals or single ions dispersed in solution, our model covers both and hence paves the way to describing aggregate formation and crystal growth processes from molecular simulations. The key to this is the use of formal  +3 and  −3 charges on the gallium and nitride ions, whilst accounting for the charge transfer in GaN crystals by means of additional potential energy terms. The latter are fitted against experimental data of GaN in the wurtzite structure and benchmarked for the zinc-blende and rock-salt polymorphs. Comparison to quantum chemical references and experiment shows reasonable agreement of structures and formation energy of [GaN]
n
aggregates, elastic properties of the bulk crystal, the transition pressure of the wurtzite to rock-salt transformation and intrinsic point defects. Furthermore, we demonstrate force field transferability towards the modelling of GaN nanoparticles from simulated annealing runs.
Stability, geometry and electronic properties of BHn (n  =  0 to 3) radicals on the Si{0 0 1}3  ×  1:H surface from first-principles
Authors: Fang C M , Mohammodi V , Nihtianov S , Sluiter M H F
Published: January 2020

A new generation of radiation detectors relies on the crystalline Si and amorphous B (c-Si/a-B) junctions that are prepared through chemical vapor deposition of diborane (B2H6) on Si at low temperature (~400 °C). The Si wafer surface is dominated by the Si{0 0 1}3  ×  1 domains that consist of two different Si species at low temperature. Here we investigate the geometry, stability and electronic properties of the hydrogen passivated Si{0 0 1}3  ×  1 surfaces with deposited BH
n
(n  =  0 to 3) radicals using parameter-free first-principles approaches. Ab initio molecular dynamics simulations using the density functional theory (DFT) including van der Waals interaction reveal that in the initial stage the BH3 molecules/radicals deposit on the Si(–H), forming (–Si)BH4 radicals which then decompose into (–Si)BH2 with release of H2 molecules. Structural optimizations provide strong local relaxation and reconstructions at the deposited Si surface. Electronic structure calculations reveal the formation of various defect states in the forbidden gap. This indicates limitations of the presently used rigid electron-counting and band-filling models. The attained information enhances our understanding of the initial stage of the PureB process and the electric properties of the products.
Monte Carlo calculation of beam quality correction factors in proton beams using TOPAS/GEANT4
Authors: Baumann Kilian-Simon , Kaupa Sina , Bach Constantin , Engenhart-Cabillic Rita , Zink Klemens
Published: January 2020

To provide Monte Carlo calculated beam quality correction factors (k

Q
) for monoenergetic proton beams using

, a toolkit based on the Monte Carlo code

.

Monte Carlo simulations of six plane-parallel and four cylindrical ionization chambers were carried out. The latest ICRU 90 recommendations on key data for ionizing-radiation dosimetry were used to calculate the electronic stopping powers and to select the mean energy necessary to create an ion pair in air (

).

factors were calculated for a 60Co spectrum at a depth of 5 g cm−2. f 

Q
factors and

ratios as well as k

Q
factors were calculated at the entrance region of monoenergetic proton beams with energies between 60 MeV and 250 MeV.

Additionally, perturbation correction factors for the Exradin A1SL ionization chamber at an energy of 250 MeV were calculated.

factors agreed within 0.7% or better, f 

Q
factors within 1.7% or better and

ratios within 2.2% or better with Monte Carlo calculated values provided in the literature. Furthermore, k

Q
factors calculated in this work were found to agree within 1% or better with experimentally determined k

Q
factors provided in the literature, with only two exceptions with deviations of 1.4% and 2.4%.

The total perturbation correction factor for the Exradin A1SL chamber was 0.969(7) and hence significantly different than unity in contrast to the assumption from the IAEA TRS-398 code of practice (CoP).

can be used to calculate k

Q
factors in clinical proton beams. k

Q
factors for six plane-parallel and four cylindrical ionization chambers were calculated and provided for the upcoming update of the IAEA TRS-398 CoP.
Spectroscopic study of plasma nitrocarburizing processes with an industrial-scale carbon active screen
Authors: Puth A , Kusýn L , Pipa A V , Burlacov I , Dalke A , Hamann S , van Helden J H , Biermann H , Röpcke J
Published: January 2020

The active screen plasma nitrocarburizing technology is an improvement of conventional plasma nitrocarburizing by providing a homogeneous temperature distribution within the workload and reducing soot formation. In this study, an industrial-scale active screen (AS) made of carbon-fibre-reinforced carbon serves as the cathode as well as the carbon source for the plasma-chemical processes taking place. The pulsed dc discharge was maintained at a few mbar of pressure while simultaneously being fed with a mixed gas flow of hydrogen and nitrogen ranging from 10 to 100 slh. Using in situ infrared laser absorption spectroscopy with lead salt tuneable diode lasers and external-cavity quantum cascade lasers, the temperatures and concentrations of HCN, NH3, CH4, C2H2, and CO have been monitored as a function of pressure and total gas flow. To simulate industrial treatment conditions the temperature of the sample workload in the centre of the reactor volume was kept at 773 K by varying the plasma power at the AS between 6 and 8.5 kW. The resulting spectroscopically measured temperatures in the plasma agreed well with this value. Concentrations of the various species ranged from 6 × 1013 to 1 × 1016 cm−3 with HCN being the most abundant species.
Optical complex integration-transform for deriving complex fractional squeezing operator*
Authors: Zhang Ke , Fan Cheng-Yu , Fan Hong-Yi
Published: January 2020

We find a new complex integration-transform which can establish a new relationship between a two-mode operator’s matrix element in the entangled state representation and its Wigner function. This integration keeps modulus invariant and therefore invertible. Based on this and the Weyl–Wigner correspondence theory, we find a two-mode operator which is responsible for complex fractional squeezing transformation. The entangled state representation and the Weyl ordering form of the two-mode Wigner operator are fully used in our derivation which brings convenience.
Nonlocal symmetries and similarity reductions for Korteweg–de Vries–negative-order Korteweg–de Vries equation*
Authors: Hu Heng-Chun , Liu Fei-Yan
Published: January 2020

The nonlocal symmetries are derived for the Korteweg–de Vries–negative-order Korteweg–de Vries equation from the Painlevé truncation method. The nonlocal symmetries are localized to the classical Lie point symmetries for the enlarged system by introducing new dependent variables. The corresponding similarity reduction equations are obtained with different constant selections. Many explicit solutions for the integrable equation can be presented from the similarity reduction.
Performance test of prototype of mini compact crucible furnace
Authors: Soemowidagdo A L , Ristadi F A , Ardian A
Published: January 2020

Mini compact crucible furnace prototype is aimed at reducing dimensions and weight without sacrificing capacity. The performance test was conducted in order to found its weaknesses. The performance parameters tested were crucible, support, and exhaust pipe as economizer. The crucible dimensions are (ø170 x 250) mm and (ø110 x 210) mm while the support’s high are 80 mm and 40 mm. The test was done in two conditions which are with and without economizer. The performance is defined by the temperature change rate in melting 3 kg of aluminium. A digital infrared thermometer was used to measure temperature changes. The result shows that position of economizer is too low so the residual gas combustion could not smoothly thrown out and it flow back and collide with the combusted gas from high pressure stove below. Reducing the heating chamber could enhance the furnace efficiency but economizer should be in proper position and support should be in optimum height. Redesign of heat insulator should be done related to the smash by combusted gas from high pressure stove.
Timekeeping strategy in the oxygen acetylene welding practicum through attendance ranking approach
Authors: Widodo S F A , Alif M , Sukardi S , Setiadi B R , Nuchron N
Published: January 2020

The culture of industry in vocational schools needs to be applied optimally to shape the work character of graduates who are increasingly fierce in competition. The trade starts to look at graduates with a better attitude than hard skills. This research is directed at how the fundamental problem of timely attendance is a phenomenon that deserves to be studied as part of the formation of soft skills. This study has objectives including (1) observing students’ participation at Oxygen Acetylene Welding (OAW) lectures and (2) reading of student attendance patterns after the implementation of timekeeping strategy-based ranking. The research method uses quantitative descriptive by collecting data by observing student attendance directly. The continuing collection was carried out for 14 weeks at the OAW practicum. Based on the results of the study showed that there was a significant increase in timely attendance and was gradually consistent until the end of the meeting. Besides, the presence sequence builds the habits of students to arrive on time.
The influence of work knowledge and industrial practice experience to learning motivation
Authors: Rofiq Z , Prananda Y , Syauqi K
Published: January 2020

This study aimed to find out the influence of work knowledge and industrial practice experience to students’ learning motivation. This study was an assosiative research with quantitative approach. The samples were decided by cluster random sampling technique. Closed-questionnaires were used to collecting the datas. Then by descriptive analysis and regression analyis technique the data were processed. The results showed there was no positive and significant influence between work knwoledge and learning motivation, shown by tcount=0, 081 < ttable=2, 069 with regression equation Y = 45, 926-0, 010X1. There was no positive and significant influence between students’ industrial practice experience and learning motivation shown by tcount=1, 056 < ttable=2, 069 with regression equation Y = 37, 464+0, 151X2. The world of work knwoledge and industrial practice experience also did not influence positively dan signficantly to students’ learning moivation simultaneously, shown by Fcount=0, 618 < Ftable=3, 39 and the regression equation Y = 38, 171-0, 080X1+0, 191X2.
Learning evaluation using work preparation in turning machine process lessons
Authors: Harjanto C T , Kartowagiran B , Maryanto A E
Published: January 2020

This study aims to implement of learning by using work preparation in the subject of turning machining in the Mechanical Engineering Major of Muhammadiyah 1 Bantul vocational high school. This research is an evaluation research. The results showed the ability of students to understand work preparation was in the high category, with a percentage in the high category 29.11%, and a very high category 24.05%. Achievement of the practice of students who completed the work preparation was in the very high category, with the percentage of achievement at job 1 of 94.36% and job 2 of 70.42 percent, so that the overall job was 82.39%. The ability of students to apply work preparation is in the high category with an average percentage of 72.67%. The completeness of the work preparation format made by the teacher is incomplete because 10 of the 18 elements that must be present in the work preparation format are not fulfilled.
The proofing validation of conventional mechanical drawing job sheet
Authors: Setiadi B R , Nuryanto A , Ahmad N D
Published: January 2020

The research aims to develop and assess the feasibility of a Job Drawing course in Mechanical Drawing (MD) in the Department of Mechanical Engineering Education, Yogyakarta State University (DMEE-UNY). This study uses the 4-D Thiagarajan model. The study was conducted at DMEE-UNY. Research subjects were media expert lecturers, content experts, and student responses. Data collection techniques using interviews and questionnaires. The questionnaire was used to evaluate the validation of expert lecturers and student responses. Data were analysed descriptively quantitatively. The results showed that the development of the job sheet was successfully carried out by the MD Semester Learning Plan (SLP) in DMEE, consisting of 43 drawing tasks divided into 13 sections. The level of eligibility of the MD course’s job sheet from the validation of content expert lecturers, media experts, and student responses stated that it was very feasible.
Approach and engineering assessment of automotive vocational engineering
Authors: Pambayun N A Y , Haryana K , Sudiyanto
Published: January 2020

This study aims to identify approaches and assessment techniques that are appropriate for vocational courses in Automotive Engineering. This research is a quantitative research with survey method. The respondents of this study were 150 alumni of the Faculty of Engineering Universitas Negeri Yogyakarta who had worked in the automotive field. Data were collected through a questionnaire, then analyzed with descriptive analysis techniques. The results showed that the most widely considered appropriate, namely, 1) assessment approach: assessment for learning (theoretical & practical courses); 3) attitude assessment techniques: observation techniques by lecturers; 4) knowledge assessment techniques: written test; 5) skills assessment techniques: assessment of practice.
The current state of the TVET teachers’ workplace learning in China
Authors: Liu H , Liu M , Hariyanto D
Published: January 2020

Workplace learning emphasizes a learning paradigm that considers learners to be active and self-directed rather than passive learning in the traditional training paradigm. The aim of this article is to try to synthesize the existing literature and studies as well as summarize the relevant information and available evidence to find the current state of teachers’ Workplace Learning in TVET (Technical and Vocational Education and Training) institute. In practice, this study will help vocational schools understand the current situation of vocational education teachers’ workplace learning and provide evidence for vocational colleges to take reformation and transformation. For the future, researchers could explore the relationships among workplace learning environment, learning strategies, and learning outcomes in the TVET context.
Applying google classroom based on prospective teacher
Authors: Prihaswati M , Mawarsari V D , Winaryati E
Published: January 2020

Teachers and prospective teachers must be technology-educated, they are equipped with technology-based that vary in knowledge which will be taught to the next industrial revolution 4.0 generation. This study aims to create a technology-educated prospective teacher. Applying Google Classroom, the teacher can distribute the assignments to give grades in one place. The target of the implementation is to increase the level of technological literacy of prospective teachers in teaching. The research is quantitative research with the data collection using a questionnaire in pretest-posttest. The results showed that there is an increase in the ability of prospective teachers after implementing of Google Classroom and prospective teachers respond well to the implementation of Google Classroom on learning.
The development of three-dimentional media chart to make golbi cleavage in sewing technology course
Authors: Wardhany T M , Suprihatin S E Y
Published: January 2020

This study aims at developing the three-dimensional (3D) media chart for Making Golbi Cleavage of Sewing Technology course in State Vocational High School 1 Depok and knowing the feasibility of the 3D media chart in making Golbi Cleavage. This media is expected to be able to help the learning process and improve the efficiency and effectiveness of learning. This research can be categorized as Research and Development with the 4D development model based on Thiagarajan. The research development was done through 4 stages, i.e. define, design, develop and disseminate. The data collection techniques were using observation, interviews, and questionnaires. The data analysis techniques used descriptive statistical analysis. The instrument validity used the construct validity and Alpha Cronbach reliability testing. The media validation of the Three-Dimensional (3D) Chart was carried out by 3 media experts, 2 material experts and the students through the small scale test on 6 students and the large scale test on 29 students. The Three-Dimensional (3D) Media Chart was considered very feasible by obtaining the percentage of 100% from the experts and 83.2% from the students. This media was feasible based on the content and the appearance aspect.
Developing a multimedia presentation for making fragments of passepoille pockets as a learning solution for the 21st century
Authors: Haqi L , Astuti E B
Published: January 2020

This study aimed to produce a multimedia presentation for making fragments of passepoille pockets and determine its feasibility level based on the assessment of theoretical experts, media experts, and students. This research was done referring to the research and development (R&D) procedure with the 4D model developed by Thiagarajan (1974). The subjects of this study were 2 theoretical experts and 1 media expert who was a lecturer of the Culinary and Clothing Department, Faculty of Engineering, Universitas Negeri Yogyakarta and the teacher of sewing technique at Vocational High School 1 Ngawen and 30 students of X class in Fashion Design. The results of this study were the developed product of multimedia presentation for making fragments of a passerelle pocket and the results of the feasibility of multimedia presentations based on the assessment of theory and media experts with the percentage of 100% (very feasible); limited trial results obtained the percentage of 88.35% (very feasible), and the real test results obtained the percentage of 94.98% (very feasible). The appropriate multimedia presentation showed that this media was suitable to be applied in the learning process based on the 2013 curriculum and it was able to help teachers and students to achieve the expected learning competencies.
Blood Collection Strategy: A Lesson Learned from Indonesian Blood Supply Chain
Authors: Mansur A , Vanany I , Arvitrida NI
Published: January 2020

Blood collection management consists of complex processes that impact the blood outdated rate. This research intends to build an effective collection strategy for the blood bank so expiration rates could be reduced. According to the observed system complexity, a suitable method in this research is discrete event simulation. Three scenarios are used in this research is the strategy of PMI in collecting the blood supply, which is a Mobile Unit Model (MUM) strategy. With the 95% minimum target of order fulfilment rate, this research is succeeded in decreasing expiration rates by 4%, by changing the supply rate of MUM, from 40 hours of time between arrivals to be 44 hours.
Platelet Inventory Management System Using Monte Carlo Simulation
Authors: Mansur A , Mar’ah FI , Amalia P
Published: January 2020

Improper of blood management will lead to wastage due to the nature of blood that is not durable and easily damaged, so if the blood is stored too much and not used until the expired date, the blood will be damaged. Platelet components have a limited lifetime for 5 days. With a short blood age, every month there will be two possibilities, one is shortage of blood inventory (stockout) or two, over blood inventory (overstock) in the storage area. From the data obtained, the expired rate in 2017 reached 743 blood bags. Until now Indonesian Red Cross has not been able to predict the level of blood demand because of the uncertain level of demand. In this study, simulation will use Monte Carlo to develop a number of policies that can optimize inventory levels and minimize inventory costs.
Evaluation of the Centralized HVAC Chilled Water Pumps of Suranaree University of Technology Hospital Main Building
Authors: Prasetyadi A , Koonsrisuk A
Published: January 2020

Pumps are the main issue of the chilled water distribution in a centralized system. In purpose of evaluating the chiller pump system of the centralized HVAC for Suranaree University of Technology Hospital (SUTH) main building, a model comprised evaporator, pump and pipe network was proposed. An analysis of energy rate losses due to pressure losses was applied in a model composed of vertical and horizontal distribution pipes. Pressure loss in pipes was assumed to follow Darcy-Weisbach equation. The resistance of the systems were also calculated. The results show that distribution of losses in vertical shaft and stories were unequal. The pressure loss and energy rate loss were function of flow-rate. But the resistance was an inverse function of the flow-rate. The difference distribution emphasized the need of reconfiguring chilled water pump for accommodating flexibility usage.
Categorization of Reliability Performance Indicators of Humanitarian Response Supply Chain
Authors: Sutrisno A , Handayani D , Caesarendra W , Gunawan I
Published: January 2020

To minimize a number of disaster victims due to certain disaster, identifying performance indicators representing reliable disaster response operation are very necessary to drive success in humanitarian action. However, literature in disaster response managements that focused on reliability performance measures are very few. To fill in this gap, in this paper presents categorization of humanitarian supply chain reliability performance indicators. This method consists of both hard and soft indicators. Our classification enables humanitarian practitioners to possibly develop unified reliability estimation indices containing of both qualitative and quantitative reliability performance indicators. At the end, conclusions and new research directions from the preliminary study are presented.
The mental workload analysis of gojek drivers
Authors: Prabaswari A D , Hamid A N , Purnomo H
Published: January 2020

Gojek is a service that is very helpful for people’s lives by opening jobs for the community and also making it easier for the community itself to live their lives. So many users of the GOJEK application, it also does not rule out the possibility of excessive passengers during rush hour. The needs of passengers who want to be fast and the needs of the company cause gojek drivers to arise workloads on the driver itself. Therefore a study was conducted by analyzing the relationship between mental workload and work stress experienced by gojek drivers using the NASA-Task Load Index (TLX) method. 30 gojek drivers were respondents in this study. By observing the indicators on NASA TLX the results obtained are as many as 3 respondents categorized as having a very high mental workload, 26 respondents having a high category and 1 respondent having a rather high category. it is necessary to improve immediately to make the work become not hampered. the workload is a significant stressor that raises a type of destructive psychological reaction.
Modelling the continuance intention towards the use of mobile hospital appointment system
Authors: Taufiq A R , Widyanti A , Muslim K , Wijayanto T , Trapsilawati F , Arini H M , Wibawa A D
Published: January 2020

Effective management of patient flow in the outpatient unit of a hospital is the key to achieving operational excellence. Hospital X, as one of the major hospitals in Indonesia, launched a mobile hospital appointment system (X-Go) to increase the effectiveness of patient flow management. Although the application has a good rating, only less than 28% of the patients are still using it. Aim of this study is to observe the factors affecting the continuance intention towards X-Go, using the Technology Acceptance Model. A questionnaire consisted of 15 questions, using 7 point Likert Scale was used to develop the model. Ninety eight respondents were involved voluntarily in this study by filling out the questionnaire. Results showed that relationship quality has the most significant direct influence on the continuance intention to use the system. Meanwhile, perceived ease of use has the most significant indirect influence on the continuance intention to use the system.
The Smart Village Model for Rural Area (Case Study: Banyuwangi Regency)
Authors: Aziiza A A , Susanto T D
Published: January 2020

Smart Village refers to a concept developed in rural area that provides solutions to problems occurred and improves the quality of life. The main problems faced by rural areas are cover poverty, low level of education, and limited access to technology. Smart village concept emerged due to some different characteristics between rural and urban areas. Banyuwangi Regency is one of regions that created smart concept starting from rural area, called smart kampung. So far, smart kampung only focused on public services, which included only a small part of smart city concept. Hence, this research was intended to propose the model of smart village examined through initial interview in village sample of Banyuwangi, literature reviews related to smart city, smart village, and smart rural. Then, the results were confirmed and adjusted to support local regulations. This research created a smart village model that was capable to be a guide for each village to develop towards better future. The proposed smart village model was categorized into 6 dimensions including 1) Governance, (2) Technology, (3) Resources, (4) Village Service, (5) Living, and (6) Tourism. This research is expected to be applied to villages in other Regencies by adjusting the characteristics of each region.
Comparison Clustering Performance Based on Moodle Log Mining
Authors: Pradana C , Kusumawardani S S , Permanasari A E
Published: January 2020

The use of digital data now saves a lot of information, but still raw and not in the form of knowledge that can be directly seen, therefore we need a data processing to get useful particular understanding from raw data. Data Mining has an important role to process and find useful information from data. This process is also called Knowledge Discovery. Educational Data Mining is a Knowledge Discovery process in the world of education using data mining techniques. One method used in data mining is clustering. By using clustering analysis techniques, data can be grouped into groups without the need for prior knowledge (previous knowledge), so that the data is grouped based on similarity of patterns. This paper compares the K-means, Hierarchical and Louvain clustering methods to see the most appropriate clustering technique in analyzing log activity data in Moodle Learning Management System (LMS). The results of clustering are measured using the Silhouette Coefficient, and then we compare the values and distribution between clusters. In conclusion, Hierarchical clustering produces the highest Silhouette Coefficient value and also this algorithm can detect outlier data as new cluster. Louvain clustering perform very well to find cluster groups in new dataset as the algorithm does not required the number of clusters to be specified before. Louvain clustering can divide more evenly and precision compare to K-means and hierarchical cluster techniques.