bluuebunny/crossref_metadata_2025 huggingface dataset:
Wideband square spiral metamaterial absorbers based on flaky carbonyl iron/epoxy composites
Authors: Yang Ruey-Bin , Yang Jyun Jhih , Lo Shen Tee
Published: January 2020

A broadband and thin microwave absorber composed of metal-base planar metamaterials (MMs) sandwiched between two layers of flaked-shaped carbonyl iron (FCI) composites is presented. FCI powder was prepared by ball milling spherical carbonyl iron powder and then added to epoxy resin to prepare FCI composite (FCIC) samples with different weight fractions. With these electromagnetic characteristics, a broadband, polarization-insensitive and thin metamaterial absorber comprising of arrays of square spirals embedded between two different layers of FCIC is optimally designed through a genetic algorithm. The reflection loss of the measured square spiral MM absorber with a thickness of 3.4 mm can reach –26 dB at matching frequency 4.4 GHz and the absorbing bandwidth below –9.3 dB is covered from 3.6 to 18.0 GHz which almost 4 fourfold bandwidth compared to that of the FCIC without the incorporation of MM layers.
Amplitude enhancement of plasma wakefield by interaction of relativistic Gaussian electron beam with inhomogeneous magnetized plasma
Authors: Sharifzadeh Tabrizi J. , Khorashadizadeh S. M. , Fallah R. , Niknam A. R.
Published: January 2020

The nonlinear dynamics of plasma wakefield in the interaction between a relativistic Gaussian electron beam and an inhomogeneous plasma is theoretically studied. The effects of physical parameters, such as the length of the driving electron bunch, the initial plasma density profile, and the static magnetic field strength on the evolution of the plasma wakefield amplitude, are discussed. It is found that the amplitudes of both the longitudinal electric field and the perturbed electron density behind the beam are larger in an inhomogeneous plasma than in a homogeneous plasma. Moreover, in a medium with periodical density variations, the change in the plasma wakefield amplitude is periodical and so the perturbed density behind the beam. It is also found that the plasma wakefield is maximum for a definite length of the drive bunch along the propagation direction. Thus, for a special system of plasmas and drive bunches, it is possible to transfer the maximum energy from a driving electron beam to the particles in the witness bunch and accelerate them to higher energies.
Optically-generated Overhauser dynamic nuclear polarization: A numerical analysis
Authors: Cheney Daniel J. , Wedge Christopher J.
Published: January 2020

Recently, an alternative approach to dynamic nuclear polarization (DNP) in the liquid state was introduced using optical illumination instead of microwave pumping. By exciting a suitable dye to the triplet state which undergoes a diffusive encounter with a persistent radical forming a quartet-doublet pair in the encounter complex, dynamic electron polarization (DEP) is generated via the radical-triplet pair mechanism. Subsequent cross-relaxation generates nuclear polarization without the need for microwave saturation of the electronic transitions. Here, we present a theoretical justification for the initial experimental results by means of numerical simulations. These allow investigation of the effects of various experimental parameters, such as radical and dye concentrations, sample geometry, and laser power, on the DNP enhancement factors, providing targets for experimental optimization. It is predicted that reducing the sample volume will result in larger enhancements by permitting a higher concentration of triplets in a sample of increased optical density. We also explore the effects of the pulsed laser rather than continuous-wave illumination, rationalizing the failure to observe the optical DNP effect under illumination conditions common to DEP experiments. Examining the influence of the illumination duty cycle, the conditions necessary to permit the use of pulsed illumination without compromising signal enhancement are determined, which may reduce undesirable laser heating effects. This first simulation of the optical DNP method therefore underpins the further development of the technology.
Microscopic modeling of transverse mode instabilities in mode-locked vertical external-cavity surface-emitting lasers
Authors: McLaren S. , Kilen I. , Moloney J. V.
Published: January 2020

The generation and control of higher order transverse modes within a mode-locked vertical external-cavity surface-emitting laser with a semiconductor saturable absorber mirror are studied using a numerical solver for the two dimensional Maxwell Semiconductor Bloch Equations. In this work, the complex spatiotemporal evolution of the pulse toward a mode-locked state depends sensitively on the pumping level and pump to pulse spot size ratio. Microscopic physics sourced effects such as kinetic hole burning and filling, occurring on femtosecond timescales, play a central role. In particular, unsaturated charge carriers, both spectrally and transversally, initiate the development of asymmetric pulse profiles that transform over various characteristic time scales in a carrier chasing behavior.
Three-axis atomic magnetometer for nuclear magnetic resonance gyroscopes
Authors: Qiu Xuyang , Xu Zhengyi , Peng Xinxin , Li Lianhua , Zhou Yinmin , Wei Mengmeng , Zhou Min , Xu Xinye
Published: January 2020

A three-axis atomic magnetometer for nuclear magnetic resonance gyroscopes (NMRGs) is demonstrated. To satisfy the miniaturization demand of NMRGs, a magnetic-resonance-based atomic magnetometer is used to detect the longitudinal magnetic field. Simultaneously, the longitudinal field is modulated to measure the magnetic field in x and y axes based on a nonlinear magneto-optical rotation magnetometer. Magnetic field sensitivities of 100 fT/Hz1/2 in x and y axes and 20 fT/Hz1/2 in the z axis are achieved. The bandwidths of this magnetometer are 96 Hz in x and y axes and 6 Hz in the z axis. A high-sensitivity three-axis magnetometer is essential to accomplish the rotation detection in NMRGs and also plays a vital role in optimizing the performance of gyroscopes.
CagA–ASPP2 complex mediates loss of cell polarity and favors
H. pylori
colonization of human gastric organoids
Authors: Buti Ludovico , Ruiz-Puig Carlos , Sangberg Dennis , Leissing Thomas M. , Brewer R. Camille , Owen Richard P. , Sgromo Bruno , Royer Christophe , Ebner Daniel , Lu Xin
Published: January 2020

Significance

Infection by the bacterium
Helicobacter pylori
is the main risk factor for stomach cancer. Strains of
H. pylori
that produce the virulence factor CagA substantially increase stomach cancer risk compared with strains without CagA. CagA disrupts cell polarity—the specialized asymmetric organization within cells—but the mechanism it uses and its influence on colonization are not fully understood. Using a three-dimensional culture of stomach cells (human gastric organoids) and cell lines, we find that the tumor suppressor ASPP2 is crucial in disruption of cell polarity by CagA during
H. pylori
infection. Interfering with the CagA–ASPP2 interaction, using small molecules or a specific peptide, blocks loss of cell polarity and reduces bacterial colonization in organoids.
Chronic Dicer1 deficiency promotes atrophic and neovascular outer retinal pathologies in mice
Authors: Wright Charles B. , Uehara Hironori , Kim Younghee , Yasuma Tetsuhiro , Yasuma Reo , Hirahara Shuichiro , Makin Ryan D. , Apicella Ivana , Pereira Felipe , Nagasaka Yosuke , Narendran Siddharth , Fukuda Shinichi , Albuquerque Romulo , Fowler Benjamin J. , Bastos-Carvalho Ana , Georgel Philippe , Hatada Izuho , Chang Bo , Kerur Nagaraj , Ambati Balamurali K. , Ambati Jayakrishna , Gelfand Bradley D.
Published: January 2020

Significance

DICER1 processes micro-RNAs into their bioactive forms and metabolizes RNAs from short interspersed nuclear element genetic repeats, principally
Alu
RNAs in humans. DICER1 deficiency is implicated in retinal pigmented epithelium (RPE) degeneration in atrophic age-related macular degeneration (AMD). Here, we report that three independent mouse models of DICER1 deficiency develop RPE degeneration and aberrant choroidal and retinal neovascularization (CRNV), both hallmarks of advanced AMD. These pathologies were dependent on inflammatory caspases 1 and 11 and the signaling adaptor MyD88. We observed reduced DICER1 abundance in a separate model of spontaneous CRNV and developed an adenoassociated vector-mediated DICER1 delivery construct, which reduced the severity of established spontaneous CRNV. Thus, persistent deficiency in DICER1 results in RPE degeneration and CRNV.
Far-field midinfrared superresolution imaging and spectroscopy of single high aspect ratio gold nanowires
Authors: Aleshire Kyle , Pavlovetc Ilia M. , Collette Robyn , Kong Xiang-Tian , Rack Philip D. , Zhang Shubin , Masiello David J. , Camden Jon P. , Hartland Gregory V. , Kuno Masaru
Published: January 2020

Significance

Traditional optical microscopy methods are limited by diffraction. This makes it hard to image and study nanostructures in the midinfrared, a relatively unexplored spectral region of chemical significance. Here we use infrared (IR) photothermal heterodyne imaging (IR-PHI), a far-field superresolution optical technique, to study the Fabry–Pérot resonances of single gold nanowires in the 2,800 to 4,000-cm
−1
region. Because the spatial resolution of IR-PHI is on the order of a few hundred nanometers, we are able to directly resolve the structure of the Fabry–Pérot resonances and assign the mode order. This cannot be done with traditional optical measurements. IR absorption spectra recorded using IR-PHI show narrow linewidths, in several cases below the limit imposed by Au’s Drude relaxation parameter.
Coordination of host and symbiont gene expression reveals a metabolic tug-of-war between aphids and
Buchnera
Authors: Smith Thomas E. , Moran Nancy A.
Published: January 2020

Symbioses between animals and microbes are often described as mutualistic, but are subject to tradeoffs that may manifest as shifts in host and symbiont metabolism, cellular processes, or symbiont density. In pea aphids, the bacterial symbiont
Buchnera
is confined to specialized aphid cells called bacteriocytes, where it produces essential amino acids needed by hosts. This relationship is dynamic;
Buchnera
titer varies within individual aphids and among different clonal aphid lineages, and is affected by environmental and host genetic factors. We examined how host genotypic variation relates to host and symbiont function among seven aphid clones differing in
Buchnera
titer. We found that bacteriocyte gene expression varies among individual aphids and among aphid clones, and that
Buchnera
gene expression changes in response. By comparing hosts with low and high
Buchnera
titer, we found that aphids and
Buchnera
oppositely regulate genes underlying amino acid biosynthesis and cell growth. In high-titer hosts, both bacteriocytes and symbionts show elevated expression of genes underlying energy metabolism. Several eukaryotic cell signaling pathways are differentially expressed in bacteriocytes of low- versus high-titer hosts: Cell-growth pathways are up-regulated in low-titer genotypes, while membrane trafficking, lysosomal processes, and mechanistic target of rapamycin (mTOR) and cytokine pathways are up-regulated in high-titer genotypes. Specific
Buchnera
functions are up-regulated within different bacteriocyte environments, with genes underlying flagellar body secretion and flagellar assembly overexpressed in low- and high-titer hosts, respectively. Overall, our results reveal allowances and demands made by both host and symbiont engaged in a metabolic “tug-of-war.”
Subsecond total-body imaging using ultrasensitive positron emission tomography
Authors: Zhang Xuezhu , Cherry Simon R. , Xie Zhaoheng , Shi Hongcheng , Badawi Ramsey D. , Qi Jinyi
Published: January 2020

A 194-cm-long total-body positron emission tomography/computed tomography (PET/CT) scanner (uEXPLORER), has been constructed to offer a transformative platform for human radiotracer imaging in clinical research and healthcare. Its total-body coverage and exceptional sensitivity provide opportunities for innovative studies of physiology, biochemistry, and pharmacology. The objective of this study is to develop a method to perform ultrahigh (100 ms) temporal resolution dynamic PET imaging by combining advanced dynamic image reconstruction paradigms with the uEXPLORER scanner. We aim to capture the fast dynamics of initial radiotracer distribution, as well as cardiac motion, in the human body. The results show that we can visualize radiotracer transport in the body on timescales of 100 ms and obtain motion-frozen images with superior image quality compared to conventional methods. The proposed method has applications in studying fast tracer dynamics, such as blood flow and the dynamic response to neural modulation, as well as performing real-time motion tracking (e.g., cardiac and respiratory motion, and gross body motion) without any external monitoring device (e.g., electrocardiogram, breathing belt, or optical trackers).
Transformative experience and social connectedness mediate the mood-enhancing effects of psychedelic use in naturalistic settings
Authors: Forstmann Matthias , Yudkin Daniel A. , Prosser Annayah M. B. , Heller S. Megan , Crockett Molly J.
Published: January 2020

Past research suggests that use of psychedelic substances such as LSD or psilocybin may have positive effects on mood and feelings of social connectedness. These psychological effects are thought to be highly sensitive to context, but robust and direct evidence for them in a naturalistic setting is scarce. In a series of field studies involving over 1,200 participants across six multiday mass gatherings in the United States and the United Kingdom, we investigated the effects of psychedelic substance use on transformative experience, social connectedness, and positive mood. This approach allowed us to test preregistered hypotheses with high ecological validity and statistical precision. Controlling for a host of demographic variables and the use of other psychoactive substances, we found that psychedelic substance use was significantly associated with positive mood—an effect sequentially mediated by self-reported transformative experience and increased social connectedness. These effects were particularly pronounced for those who had taken psychedelic substances within the last 24 h (compared to the last week). Overall, this research provides robust evidence for positive affective and social consequences of psychedelic substance use in naturalistic settings.
Multimodal processing in simultaneous interpreting with text
Authors: Chmiel Agnieszka , Janikowski Przemysław , Lijewska Agnieszka
Published: January 2020

The present study focuses on (in)congruence of input between the visual and the auditory modality in simultaneous
interpreting with text. We asked twenty-four professional conference interpreters to simultaneously interpret an aurally and
visually presented text with controlled incongruences in three categories (numbers, names and control words), while measuring interpreting
accuracy and eye movements. The results provide evidence for the dominance of the visual modality, which goes against the
professional standard of following the auditory modality in the case of incongruence. Numbers enjoyed the greatest accuracy across
conditions possibly due to simple cross-language semantic mappings. We found no evidence for a facilitation effect for congruent
items, and identified an impeding effect of the presence of the visual text for incongruent items. These results might be
interpreted either as evidence for the Colavita effect (in which visual stimuli take precedence over auditory ones) or as
strategic behaviour applied by professional interpreters to avoid risk.
Fungal community dynamics during degradation of poly(butylene succinate-co-adipate) film in two cultivated soils in Japan
Authors: Yamamoto-Tamura Kimiko , Hoshino Yuko Takada , Tsuboi Shun , Huang Chuan , Kishimoto-Mo Ayaka Wenhong , Sameshima-Yamashita Yuka , Kitamoto Hiroko
Published: January 2020

Fungi play an important role in the degradation of biodegradable plastics (BPs) in soil. However, little is known about their dynamics in the soil during the degradation of BPs. We studied the community dynamics of BP-degrading fungi during poly(butylene succinate-co-adipate) (PBSA) film degradation in two different types of soils using culture-dependent and culture-independent methods. The Fluvisol and the Andosol soils degrade embedded PBSA films at high and low speeds, respectively. The number of PBSA emulsion-degrading fungi that increased in the Fluvisol soil was higher than that in the Andosol soil after embedding with PBSA films. We succeeded in detecting internal transcribed spacer 1 (ITS1) regions those matched that of the fungi by polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE) in both soils. Our results suggest that fungal community analyses using PCR-DGGE in combination with BP degraders isolation techniques enables the monitoring of BP films-degrading fungi.
NuMA1 facilitates the assembly of the axon initial segment by promoting the retention of neurofascin-186
Authors: Abouelezz Amr , Hotulainen Pirta
Published: January 2020

Axon initial segment (AIS) functionality relies on a specific organization of the AIS with high enrichment of structural and functional proteins. In this issue, Torii et al. (2019. J. Cell. Biol.https://doi.org/10.1083/jcb.201907048) describe a mechanism for achieving a high density of proteins in the nascent AIS.
Iannis Aifantis: An accidental scientist
Authors: Houston Stephanie
Published: January 2020

Iannis Aifantis is a principal investigator at NYU Langone Medical Center, and his laboratory works on the molecular mechanisms that drive normal stem cell differentiation and malignant transformation. Specifically, they’re interested in the genomic, epigenetic, and proteomic regulation of hematopoietic stem cell differentiation and the induction of leukemia and lymphoma; some of their basic research has led to clinical trials in leukemia and myelodysplastic syndromes. I chatted with Iannis to find out about his career in science so far.
Analytical results for the dynamics of parabolic level-crossing model
Authors: Kam Chon-Fai , Chen Yang
Published: January 2020

We study the dynamics of a two-level crossing model with a parabolic separation of the diabatic energies. The solutions are expressed in terms of the tri-confluent Heun equations—the generalization of the confluent hypergeometric equations. We obtain analytical approximations for the state populations in terms of Airy and Bessel functions. Applicable expressions are derived for a large part of the parameter space. We also provide simple formulas which connect local solution in different time regimes. The validity of the analytical approximations is shown by comparing them to numerical simulations.
Preliminary study of fragment simulating projectile on epoxy-ramie composite
Authors: Mukhammad A F H , Murni  , Mujiyono  , Nurhadiyanto D , Hassan S A , Riyadi T W B
Published: January 2020

This research is a preliminary study to determine the feasibility of the ballistic test equipment using fragment-simulating projectiles (FSP) and the ability of the rami-epoxy composite against bullet penetration. Tests have been conducted in which FSP were fired at epoxy ramie composites. Ballistic test equiment was equipped with a chronograph and high speed camera. The composites were manufactured using manual hand lay-up compression moulding 60% volume fraction. Based on the high speed camera result shows that the FSP projectile when crashing into the specimen was not in perfect position (tilted) and the ramieepoxy composite was fail in 6, 9, and 12 layers.
Development of interactive learning media in producing straight gears of milling subjects
Authors: Rahdiyanta D , Prasetya H T , Rezani R
Published: January 2020

This study aims to develop interactive learning media produce straight gears in subjects of milling machining. This type of research is research and development. Media development procedures include the identification stage, the design and development stage, the validation stage, user responses and the final product results. Data collection techniques are done by observation, interviews and questionnares. Data analysis techniques using quantitative descriptive techniques. This research resulted in an interactive learning media produce straight gears at 284 MB in the form of files. exe which is equipped with images, video, audio and animation. Assessment of the appropriateness of interactive learning media produce straight gears from media experts get grades with very good categories, from material experts get assessments with good categories, from teachers get grades in very good categories, and from student responses get grades in very good categories.
The development of mechanical drawing job-sheet for vocational high school instructional
Authors: Nuryanto A , Rahayu N S , Setiadi B R
Published: January 2020

This study aims to develop a mechanical engineering drawing job sheet and determine the feasibility of the media. This research uses research and development by referring to the Four-D development model (define, design, develop, disseminated). Data collection techniques with observation and interviews. The instrument used was a non-test instrument in the form of a closed questionnaire with a Likert scale of five answer choices. The results showed that the job sheet learning media was carried out with several steps, namely defining needs, designing, developing and distributing. The feasibility of the job sheet media for learning engineering drawings based on the results of the validation of media experts has a score of 4.58 and a material expert score of 4.66 which is included in the very feasible category. The results of teacher user responses with a mean score of 4.21 and 4.5 students in a very feasible category.
Analysis of multi-cell hexagonal crash box design with foam filled under frontal load model
Authors: Choiron M A
Published: January 2020

This study aim is to determine the effect of Multi-Hexagonal crash box design variations on energy absorption. The research method used ANSYS Academic software version 18.1. The crash box model analysed consists of 3 models, namely the multi-cell hexagonal outer foam filled crash box, inner foam filled and without foam filled. Crash box testing refers to the instrumented drop mass setup test model, impactor with a mass of 103 kg crashing crash box with a speed of 7.67 m/s. Deformation pattern and energy absorption are observed as design criteria to determine the best crash box design specifications. The simulation results show that the highest energy absorption value is the multi-cell hexagonal outer foam filled crash box with that Ea is 30, 606 kJ. There is a significant difference between the multi-cell hexagonal crash box model with foam filled and without foam filled. The addition of foam filled on the multi-cell hexagonal crash box has important effect to improve energy absorption performance. The deformation pattern that occurs in all three models is concertina mode. Based on the force reaction-displacement curve, it can be denoted the crash box that uses foam filled produces upward trend of curves in the end of the deformation. It can be connected to deformation pattern, folding increment is more identified compared to crash box without foam filled.
The analysis of machining job risk in vocational workshop
Authors: Djatmiko R D , Adhitama R K , Prasetya T A
Published: January 2020

This study was purposed to identify the hazards that might occurred in the machining workshop of Public VHS of 2 Wonosari, identify the probabilities that might occurred in machining workshop of Public VHS of 2 Wonosari, identify the risks that would occur in machining workshop of Public VHS of 2 Wonosari, and recognize how the workshop management, teachers and schools controlled and prevented the risks in the machining workshop, in order to avoid the accidents in the machining workshop of Public VHS of 2 Wonosari. This research was descriptive. Data was obtained through observation, interviews and photographic documentation of machining workshop conditions. The validity of the data was done by testing credibility, dependability and confirmation test. Data analysis was using Miles and Huberman analysis methods, by reducing data, presenting data and drawing the conclusions or verification. The results of the study proved that there were 29 hazards sources which identified in the machining workshops, there were 30 opportunities probability which identified in the machining workshop, there were 31 risks which identified in the workshops if without accurate treatment, and the average of risk control in the machining workshops was 86.0%.
The effectiveness of internship information system application in vocational high school
Authors: Purnomo E , Pratama Y R , Rezani R
Published: January 2020

This study aims to determine the implementation of the internship information system application in vocational high school (VHS), measure the effectiveness of the internship information system application in VHS and determine the appropriateness of the internship information system application as media in VHS. Research conducted at VHS of Muhammadiyah Prambanan uses quantitative approach with a descriptive method. Samples were taken using a random sampling technique. Data collection techniques used were observation and questionnaires where the data are analysed using descriptive analysis and quantitative data analysis. The results of this study indicate that the implementation of internship information system by 73%. The level of effectiveness of internship information system applications, including both categories. The details are quality systems 72%, the quality of information 74%, quality of service 70% user satisfaction 71% and profit 70% as well as the application of internship information system fit for use as a media internship services with the percentage of the effectiveness of the application of internship information system by 71% and internship service by 72%.
Implementing student teams-achievement division to improve student’s activeness and achievements on technical drawing courses
Authors: Sutopo  , Wibowo A N , Wibowo Y E
Published: January 2020

The purpose of this research is to find out the process of cooperative learning action type student teams achievement division (STAD) and its effect on the activeness and learning outcomes of students in class X Mechanical Engineering of Vocational High School 2 Depok Sleman. This research is a classroom action research using STAD type cooperative learning model, using a qualitative approach to compare the results of observations of cycle I, cycle II, and cycle III. The results of the study show that the implementation of the STAD type cooperative learning model can increase student activity and learning outcomes in each cycle. There are increasing in learning activeness of students who received the minimum score of good categories and increasing in the number of students who received the minimum completion criteria.
ICT-based learning media development
Authors: Setuju  , Ratnawati D , Wijayanti A , Widodo W , Setiadi B R
Published: January 2020

This research aimed at developing ICT-based learning media for independent learning. The subjects of the research were Mechanical Engineering students of Universitas Sarjanawiyata Tamansiswa. By adopting Borg & Gall’s research and development model, this research was done in four stages, namely: (1) identification stage; (2) design and development stage; (3) production stage; and (4) evaluation stage. Questionnaires were the instrument used for data collection techniques, and the descriptive quantitative method was the data analysis technique. The results of the development of ICT-based learning media earned positive appraisals on the ease of use aspect with a percentage of 50%, and the display aspect with a percentage of 62.50%. In conclusion, ICT-based learning media that was developed on several vocational materials can be used as a learning media for independent learning.
Developing heat sink method in gas metal arc welding to minimize distortion
Authors: Wibowo H , Djatmiko R D , Marwanto A
Published: January 2020

Efforts to minimize distortion of welding results need to be done, considering that it can reduce the accuracy of the weld dimensions, increase the repair process, and increase the production costs. This study aims to reduce distortion by the heat sink (HZ) method and its effect on mechanical properties. The heat sink method was applied in conjunction with Gas Metal Arc Welding (GMAW) process by liquid nitrogen coolant with a variable of the HZ’s contact area. The HZ areas of contact were designed in 3 dimensions, namely 10 L, 20 L, and 30 L, and it was placed on the surface of the plate with 10 mm space from the welding line. The results show that the surface area in contact with the coolant affects the quality of the welding joint. Based on visual tests, the greater the HZ’s contact area, the greater the defected impacts due to the lack of penetration. Besides, the greater the surface area of the HZ, the more effective it is to minimize welding distortion, especially the distortion in the longitudinal direction. The HZ contact area has somewhat little influence on the hardness and microstructure of the weld metal (WM) and heat affected zone (HAZ), but probably does not affect the tensile strength of the welding joint.
The risk analysis of rice husk of co-firing fuel for boilers in sugar mills
Authors: Yunaidi  , Surahmanto F , Harnowo S
Published: January 2020

Biomass is a very important energy source in the sugar mill industry as the main fuel in the power plant boilers. The efficiency of boilers for most sugar mills in Indonesia is quite low and the availability of bagasse is lacking so that in its operations, co-firing has to be applied with an alternative biomass fuels such as rice husk, cane trash, wood and saw dust. Based on the analysis, rice husk has a lower calorific (3248 cal/gr) value than that of bagasse (4076 cal/gr), but it has a higher ash content (20.67%) than that of bagasse (3.66%), so adjustments in boiler operation is required when using rice husk as co-firing. The higher ash content in biomass can affect the performance of the furnace and superheater in the boiler and increase the potential for deposit formation. The composition of rice husk ash was dominated by silica (SiO2) which reached 95.52%. It is higher than the silica content of bagasse which reached 74.99%. The high silica content in rice husks has the potential to conduce melting ash in boiler grate. The alkali content of rice husk which was around 3.64% is less than that found in bagasse which reached 17.33%. Even though, the ash composition analysis shows quite small potential for slagging, fouling, melting, sintering, and agglomeration, but the large amount of ash content in rice husks can increase the potential for the occurrence of the risks.
Utilisation of mind map and TPACK within-pair check to enhance communication skill
Authors: Wijayanti A , Widyawati A , Septiani D , Setuju S , Widowati A , Kusdiyanta A
Published: January 2020

The urgency of improving skills is a problem in one of the schools in Yogyakarta, especially communication skills in learning. Therefore, this study aims to improve communication skills by utilising mind mapping and TPACK (Technological Pedagogical and Content Knowledge) in a pair of checks. The subjects of this study were thirty-eighth-grade students of Junior High School (JHS) of 5 Banguntapan Yogyakarta, totalling thirty-two students. This research is qualitative research with a class action research design. Classroom action research by referring to the Kemmis & McTaggart model, namely through stages (1) planning; (2) implementation; (3) observation; (4) reflection. The four stages are carried out in cycles. Data collection is done by observation, questionnaire and documentation. Observations were made to find out the pair of mind check assisted with mind maps. The questionnaire is filled in by students to find out communication skills. Documentation to document student and teacher activities during pair check assisted with a mind map. Data analysis techniques using quantitative descriptive analysis with percentages and qualitative descriptive. The results showed that the average communication skills increased by 5.55%.
Pedagogical competence of productive lesson teachers of vocational high schools in Banten province
Authors: Ramdani S D , Burhanudin  , Fawaid M , Abizar H , Fatkhurokhman M
Published: January 2020

This study aims to reveal the pedagogical competence of productive subject teachers in Banten Province in the learning process, the urgency of the pedagogical competency aspects of productive subjects and the perception of productive subjects’ teachers on pedagogical competencies. This research is a quantitative descriptive study conducted in 16 Vocational High Schools in Banten Province. Data collection techniques used were questionnaires, observations, and interviews. The data analysis technique used is descriptive statistical analysis. The results of the study are as follows: (1) The pedagogical competence of productive subject teachers in Vocational High Schools in Banten Province is generally included good category, (2) the urgency of the pedagogical competence of productive subject teachers at Vocational High Schools in Banten Province is generally included fundamental category, and (3) teacher teaching and learning activities there are still difficulties in the application of pedagogical competencies. Efforts by teachers to improve competence and knowledge are in participating in workshops and discussions with peers to increase knowledge and knowledge.
Development of mechanics techniques learning media-based three-dimensional flipbook
Authors: Setiyo E , Harlin  , Kistiono
Published: January 2020

This research aims to produce a valid and practical three-dimensional-based learning media. This research was a research and development. Materials and media experts assessed the validation of this learning media. The results of this study showed a valid learning media with excellent categories by media expert assessment. Assessment by materials expert showed in the good category. Based on a small group test and field test, the product practically was in useful categories.
Optimal knot selection in spline regression using unbiased risk and generalized cross validation methods
Authors: Utami T W , Haris M A , Prahutama A , Purnomo E A
Published: January 2020

Spline regression is a nonparametric regression method that estimates data patterns that do not form certain patterns with the help of knots. The best model is obtained from the optimal knot. There are several methods that can be used to select optimal knots, including Generalized Cross-Validation (GCV) and Unbiassed Risk (UBR). The best model selection criteria used are based on the Mean Squared Error (MSE) and R-Square values. This study discusses the comparison of spline regression models using the UBR and GCV methods as a method for selecting optimal knots in data generation simulations. This research resulted in the best nonparametric spline regression model from the UBR method obtained by using three knots which produced an MSE value of 738.67 and R -Square of 85.65%. Whereas, the best nonparametric spline regression model of the GCV method was obtained using three knots which produced an MSE value of 121.43 and R-Square of 97.64%. It can be concluded that the more appropriate method used for the selection of optimal knot is the GCV method because it produces a smaller MSE value and a larger R-Square compared to the UBR method.
Assessing the indicators of economic growth in Indonesia using spatial principal components analysis
Authors: Karim A , Utami T W , Fathurohman A , Setyowati C I , Suhartono  , Prastyo D D
Published: January 2020

The objective of this study is to reduce the number of indicators that affect correlated economic growth into the main component variables. The variables used Gross Regional Domestic Product (GRDP) (X1), Foreign Direct Investment (X2), Domestic Direct Investment (X3), Employment (X4), Human Community (X5), Export (X6), and Import (X7). The data used are secondary data taken from Statistics Indonesia in 2018. This study uses the Geographical Weighted Principal Component Analysis (GWPCA) with the kernel weighting used is exponential kernel weighting. The results of this study are the main component variables or new variables that can be explained about 89% of the original variables. Based on the first main component (PC1) which consists of three groups of variables that affect economic growth indicators, namely: the area of which economic growth indicators are influenced by the Human Resources variable (X5) followed by the GRDP variable (X1), the region whose indicators of economic growth are influenced by the Export variable (X6) is followed by the Import variable (X7), and the region which is an indicator of economic growth is influenced by the Import variable (X7) is accepted by the Export variable (X6).
Modelling of spatial lag of X regression in the School Operational Aid
Authors: Wasono R , Karim A , Darsyah M Y , Ismunarti D H , Suwardi
Published: January 2020

The issue of the allocation and distribution of the School Operational Aid (BOS) in Central Java Province is a complex problem since each region has different characteristics. The distribution formulation requires a spatial model as the neighbouring regions have dependencies. The variables in this research were BOS value, supervision/building cost, management cost, Human Development Index (HDI) analysed using the Spatial Lag of X (SLX) model with the weighting of Rock Contiguity. It is concluded that all variables have a spatial dependency with the BOS variable influenced by the variables of building and management costs significantly.
The feasibility of an android-based e-module to support learning PLC applications as controllers for automatic bottle filling and capping machines
Authors: Sukir  , Nurkhamid  , Nurdiyansyah
Published: January 2020

The objective of this study was to determine the performance and the feasibility of an Android-based e-module to support the learning process of PLC applications as the controller of automatic bottle filling and capping machines in the competency of Electrical Power Engineering Skills in SMK N1 Pundong, Bantul. The method applied was research and development that refers to the ADDIE model from Branch. The results revealed that the developed Android-based e-module named PLC TOI Module in the .apkfile format, showed good performance indicated by all menus that function properly. In addition, thee-module has a very high feasibility level to be applied in the learning process, proven by a combined score of 84.46% from the material and media expertsvalidation, and students’ response.
Functional test of the online Recognition of Work Experience and Learning Outcome System using black box testing
Authors: Zamtinah  , Supriyadi E , Soeharto
Published: January 2020

This paper describes: (1) the development of the online Work Experience and Learning Outcome (ReWELO) website, (2) the feasibility testing of the online ReWELO system, and (3) the functional testing of the ReWELO system using black-box testing. The method used to develop the ReWELO website was the design method. The instruments used for testing were questionnaires and observation sheets. The instrument’s validity was tested through expert judgment and the instrument’s reliability was examined with Cronbach’s Alpha. The feasibility of the website was analyzed by information technology experts and users (assessors and candidates). The function of the ReWELO Website was tested by using black-box testing. The collected data were then analyzed descriptively. The test results revealed that ReWELO’s website was rated “good” by information technology experts, assessors, and candidates. The average score of evaluation from information technology experts, practitioner, assessors, and candidates were 3.3; 3.5; 3.4; and 3.2 respectively. All features of the online ReWELO system were able to function properly as planned.
Safety education management in welding robotic laboratory
Authors: Ismara K I , Prianto E
Published: January 2020

The purpose of this study is to develop the OSH education management system for the laboratory of the welding robot arm. This study employed Research & Development (R & D) with the ADDIE model. The research consisted of two industries that have used welding robotic arms and the vocational schools of technology, which have welding workshops. The feasibility of the research results was done through audit-trail triangulation from relevant experts, i.e educators, competency test assessors, operators and/or experts from the industry. The results were in the form of the OSH for educational management system and the redesign draft of vocational education laboratory model on welding techniques using robotic arms to accommodate OSH, 5S - Seiri (Sort), Seiton (Set in order), Seiso (Shine), Seiketsu (Standardize) and Shitsuke (Sustain) and the ergonomics of the room. The results of the needs analysis related to the welding robot arm of the industrial arm are used as the basic pattern to redesign, develop and to compile the implementation of the welding education laboratory model assisted by robotic arms and complete with the OSH education management system.
The development of interactive android-based learning multimedia on the beef and its processing results course
Authors: Ayuningtyas F B , Rinawati W
Published: January 2020

This study aimed to develop interactive multimedia based on android on the course of beef and its processing results and to know its feasibility based on the material experts, the media experts, the teachers, and the students. This research can be categorized as Research and Development (R&D) with ADDIE model, namely Analysis, Design, Development, Implementation, and Evaluation. This study only covers the implementation stage. The results of the study showed that the development of multimedia includes analyzing students’ needs, designing multimedia products, making multimedia products with Adobe Flash CS6 software and validating with experts, testing the multimedia products to 24 students. The validation results revealed that the development of multimedia in the small-scale test in the case of the linguistic aspect was 83.38%, the presentation aspect was 82.25%, the interactive learning aspect was 86%, and the overall viewing aspect was 80%, respectively. These results indicate that these android-based interactive learning multimedia is very suitable to be used as a learning media for Food Material Knowledge with the Basic Competence of Analyzing Food Materials from beef and its procession results.
The relevance of airframe powerplant competencies in Bina Dhirgantara vocational high school with the aviation industry
Authors: Hariyanto E
Published: January 2020

The level of relevance of airframe powerplant expertise competencies with industry affects the opportunities for students to work in the industry according to their area of expertise. For this reason, it is important in this research to conduct research on the Relevance of Airframes Powerplant Competence of Vocational High School Bina Dirgantara with the aviation industry. The method used in this research uses descriptive qualitative case study research. The population in this study was the competence of students of class XII Airframe Powerplant expertise at the Bina Dhirgantara Aviation Vocational School taken randomly. Based on data analysis, the results of this study show that: Competence of airframe and powerplant expertise in Vocational School Bina Dhirgantara Surakarta on average 65% of learning at Vocational School Bina Dirgantara is less relevant to the industrial world.
The nexus between financial literacy and entrepreneurship ability among university students in emerging markets
Authors: Ogbolu A N , Sukidjo
Published: January 2020

This study investigates the level of financial literacy and entrepreneurship ability among university students in emerging markets while examining the relationship between university student’s financial literacy level and their entrepreneurial abilities. Data was collected by distributing 90 questionnaires to students of Yogyakarta State University, Indonesia covering cross educational majors. Out of the sample, a total of 84 returned completed questionnaires were used for analysis. The findings from this study revealed that 45% of the respondents were able to answer one of The Big 3 financial literacy questions correctly, 21.4% answered two questions correctly while none answered all three questions correctly. This implies that the level of financial literacy Yogyakarta State University is low and corroborates findings of similar studies done in Indonesia. However, the respondents reported a high level of entrepreneurial ability as almost 80% of the respondents reported having satisfactory levels of entrepreneurial abilities, 7% had an outstanding entrepreneurial ability while the remaining 13% had a considerable level of entrepreneurial ability. Using Pearson correlation analysis, the study revealed that although financial literacy and entrepreneurial ability are positive related, the relationship is however not statistically significant at alpha 5%.
The effect of the occupational health and safety practices on the boutique production quality
Authors: Fatimah I , Jerusalem M A
Published: January 2020

This study aims to find out: (1) the application of occupational health and safety in boutiques in the Special Region of Yogyakarta, (2) the quality of boutique productions in the Special Region of Yogyakarta, and (3) the effect of occupational safety health on the quality of boutique productions in the Special Region of Yogyakarta. This study can be categorized as an associative study using a survey method and a descriptive study related to fact collection, identification, and prediction of relationships within and between variables. The sample was selected using the random sampling technique referring to Isaac and Michael’s formulas with the error margin of 5%. From a population of 35 employees, the sample consisted of 32 employees was selected. The data were analyzed using the descriptive analysis technique. The hypothesis testing used the product-moment test. The study was conducted at Seyvia Charis Couture and Bridal Boutique, Gavrilla Fashion Studio, and Punky Rima Design of Indonesia. The results of the study are as follows. 1) The OSH application by boutiques in Yogyakarta was very good. This showed that employees and leaders have implemented occupational health and safety very well with the score of 1901 that can be categorized as very good. 2) The quality of boutique productions in Yogyakarta as a whole obtained the score of 2303 that can be categorized as very good. 3) The effect of the OSH application on productions is very strong on the stage of the production process with the correlation coefficient of 0.676 but it is getting weak on the final preparation and completion stages with the correlation coefficients of 0.426 and 0.330, respectively.
Studies on Nickel-based Bimetallic Catalysts for the Hydrodeoxygenation of Stearic Acid
Authors: Rafiani A , Aulia F , Dwiatmoko A A , Rinaldi N , Nurhasni  , Widjaya R R
Published: January 2020

Fatty acids, which are contained in vegetable oils, can be converted into alkanes through the hydrodeoxygenation (HDO) reaction, as an alternative fuel. In this study, the HDO of stearic acid was carried out in the presence of nickel-based bimetallic catalysts supported on Silica-Alumina (SiAl) in an autoclave batch reactor using decane as a solvent. Various metals, including Fe, Cu, and Co, were added into Ni catalysts using conventional wet impregnation method. Among others, additional Cu on Ni/SiAl increased the performance of the catalyst for the reaction.