bluuebunny/crossref_metadata_2025 huggingface dataset:
Observation of weakly damped modes using high resolution measurement of turbulence in a dipole confined plasma
Authors: Qian T. M. , Mauel M. E.
Published: January 2020

When plasma is confined by a levitated superconducting current ring, the turbulent radial particle flux changes the direction depending upon the gradient of the particle number within tubes of equal magnetic flux [Garnier et al., Phys. Plasmas 24, 012506 (2017)]. When the density profile is highly peaked, the particle flux is outward. When the density profile is less peaked, turbulence drives an inward “particle pinch.” This change in the direction of particle flux coincides with a reversal of the mean toroidal propagation direction of turbulent fluctuations. Previously, only the mean wavenumber of the fluctuations was reported. The mean wavenumber was computed from the ensemble correlation between two probes. Here, the full frequency-wavenumber power spectrum of the saturated turbulence is calculated by applying Capon's “maximum likelihood method” to floating potential measurements from an array of probes. The power spectrum shows that the highest intensity modes are due to unstable entropy modes, and the less intense modes coincide with weakly damped convective cells, which rotate toroidally in the direction opposite to the unstable modes. Because the weakly damped modes make up a significant fraction of the fluctuating power, these measurements imply that saturated turbulence in a dipole-confined plasma involves the excitation of weakly damped rotating convective cells.
Rectification behavior of polarization effect induced type-II n-GaN/n-type β-Ga2O3 isotype heterojunction grown by metal organic vapor phase epitaxy
Authors: Li Weijiang , Zhang Xiang , Zhao Jie , Yan Jianchang , Liu Zhiqiang , Wang Junxi , Li Jinmin , Wei Tongbo
Published: January 2020

We demonstrated the growth of high-quality and compressive-stressed single-crystal c-GaN on (2¯01) β-Ga2O3 utilizing metal organic vapor phase epitaxy. Rectification behavior of the n-GaN/n-Ga2O3 isotype heterojunction was observed. Valence and conduction band offsets were determined to be 1.625 eV ± 0.07 eV and –0.165 eV ± 0.07 eV, respectively, confirming a type-II heterojunction due to the polarization effect. The extracted forward (0.702 V) and reverse (0.178 V) turn-on voltages could be ascribed to the band bending (0.695 eV) effect and the conduction band offset, respectively. The present work may lead to a deeper understanding of the GaN/β-Ga2O3 heterojunction and play a guiding role in the development of the GaN-based vertical structure light-emitting diodes on β-Ga2O3.
Development of microfluidic concentrator using ion concentration polarization mechanism to assist trapping magnetic nanoparticle-bound miRNA to detect with Raman tags
Authors: Chen Wen-Yu , Wang Chih-Hsien , Wang Kai-Hao , Chen Yuh-Ling , Chau Lai-Kwan , Wang Shau-Chun
Published: January 2020

MicroRNAs (miRNAs) are small noncoding single-stranded ribonucleic acid molecules. This type of endogenous oligonucleotide could be secreted into the circulation and exist stably. The detection of specific miRNAs released by cancer cells potentially provides a noninvasive means to achieve early diagnosis and prognosis of cancers. However, the typical concentration of miRNAs in blood is below the ultratrace level. This study uses a simple thermoplastic microfluidic concentration device based on an ion concentration polarization mechanism to perform enrichment and cleanup and Raman sensing beads to determine miRNA quantitatively. One sample solution containing target miRNA molecules having been hybridized with two nucleotide probes, where one probe is on a Raman tag of a nanoaggregate embedded bead (NAEB) and the other probe is on a magnetic nanoparticle (MNP), is first filled into the device. When an external field is applied across a cation exchange membrane stationed in the middle conduit of the device, the MNP-miRNA-NAEB complexed particles are enriched near the membrane edge of the cathode side. The concentrated complexed particles are further trapped using an external magnet to perform washing steps to remove excess noncomplexed NAEBs. When cleanup steps are accomplished, the remaining complexed particles are loaded into one detection capillary to acquire Raman signals from the sensing beads. Compared with that using a conventional magnetic trapping device, the cleanup time is shortened from nearly an hour to less than 10 min. Sample loss during the washing steps becomes more controllable, resulting in adequate standard curve linearity (R > 0.99) ranging from 1 to 100 pM.
Experimental investigation of interactions between turbulent cylinder wake and spherical shock wave
Authors: Aruga Kenta , Inokuma Kento , Watanabe Tomoaki , Nagata Koji , Sakai Yasuhiko
Published: January 2020

Interactions between a spherical shock wave and a turbulent cylinder wake are studied with wind tunnel experiments. The shock wave is generated outside the wake and propagates across the turbulent wake. Instantaneous streamwise velocity is measured on the wake centerline while peak overpressure of the shock wave is measured outside the wake after the shock wave has passed across the wake. The experiments are performed for various conditions of the cylinder wake to investigate the influences of the root-mean-squared (rms) velocity fluctuation and of the length of the turbulent region through which the shock wave propagates. The velocity fluctuation opposite to the shock propagation direction is positively correlated with the peak-overpressure fluctuation. The mean peak overpressure decreases after the shock wave propagates in the wake. These relations between velocity and peak overpressure are explained by the shock-surface deformation, where the peak overpressure is increased and decreased, respectively, for the shock surfaces with concave and convex shapes in relation to the shock propagation direction. The correlation coefficients between the velocity and peak-overpressure fluctuations and the rms peak-overpressure fluctuation increase with the rms velocity fluctuation. The rms peak-overpressure fluctuation becomes independent of the turbulent length on the shock ray once the shock wave has propagated through a sufficiently long turbulent region. The peak-overpressure fluctuation has a probability density function (PDF) close to a Gaussian shape even though the PDF of velocity fluctuations in the wake is negatively skewed.
A comparative study of the operational characteristics of CdSe quantum dots and BeZnCdSe quantum well laser diodes
Authors: Akimoto Ryoichi
Published: January 2020

In this study, the operational durability of laser diodes (LDs) with CdSe quantum dot (QD) active region is examined through a detailed comparison with its BeZnCdSe quantum well (QW) counterpart. To focus on the impact on the difference caused by the nature of the active region, other layers such as the waveguide layer, cladding layer, and contact layer, which influence the mode profile of the optical confinement and electrical properties, are maintained under the same condition. Although the threshold current of the CdSe QD LD is higher than that of the BeZnCdSe QW LD by a factor of 1.6–1.7 under a fresh condition, the degradation of the former proceeds much more slowly than that of the latter. This is confirmed by a reliability test conducted under the current injection condition both below and above the lasing threshold. The result indicates that the stronger carrier localization in the CdSe QDs compared to that in the BeZnCdSe QWs prevents the interaction with remote defects in the active layer. Consequently, the CdSe QD LD is less sensitive to degradation due to recombination-enhanced defect reactions.
Exchange bias in La0.7Sr0.3CrO3/La0.7Sr0.3MnO3/La0.7Sr0.3CrO3 heterostructures
Authors: Olmos Rubyann , Iturriaga Hector , Blazer Dawn S. , Koohfar Sanaz , Gandha Kinjal , Nlebedim Ikenna C. , Kumah Divine P. , Singamaneni Srinivasa R.
Published: January 2020

In the recent past, heterostructures of magnetic oxide thin films have attracted a great deal of research excitement due to very interesting physical properties such as antiferromagnetic interlayer coupling, tunable exchange-bias, interfacial driven magnetic properties and high mobility electron gas across the interfaces. In this work, we report on the comprehensive magnetic properties observed from the heterostructures of (2 unit cells) La0.7Sr0.3CrO3/(8 unit cells) La0.7Sr0.3MnO3/(2 unit cells) La0.7Sr0.3CrO3, which are epitaxially deposited on SrTiO3 substrate by plasma-assisted oxide molecular beam epitaxy. Using SQUID magnetometer, the magnetic properties are studied when the magnetic field was applied both in plane and out of plane. The Curie temperature of this structure is found to be at 290 K. Most significantly, at 2 K, we observed a complete up/down shift (along magnetization axis) of hysteresis loop when the sample was cooled under a magnetic field of ± 5000 Oe in the in-plane configuration. We believe that the strong antiferromagnetic (super) exchange coupling of Mn-Cr across the two interfaces is responsible for the observed exchange bias. We will present and discuss our in-detailed experimental findings collected on this heterostructure as a function of temperature and magnetic field.
Lateral straggling of implanted aluminum in 4H-SiC
Authors: Müting J. , Bobal V. , Neset Sky T. , Vines L. , Grossner U.
Published: January 2020

The implantation of aluminum into 4H-SiC is studied using secondary ion mass spectrometry. In particular, two-dimensional concentration profiles are obtained, which allow the investigation of lateral straggling and its dependence on the crystallographic orientation. A high dose, medium energy aluminum implantation is studied in great detail. It shows an asymmetric distribution due to the 4°-off axis growth of the epitaxial layer. The lateral straggling is found to be in the range of several micrometers for a concentration of 1×1015 cm−3, which is contrary to the expectation given by most simulation studies. Implantations performed at different orientations support the idea that lateral straggling highly depends on the particular channeling opening.
Thermomagnetic control of spintronic THz emission enabled by ferrimagnets
Authors: Fix Mario , Schneider Robert , Bensmann Jannis , Michaelis de Vasconcellos Steffen , Bratschitsch Rudolf , Albrecht Manfred
Published: January 2020

In this Letter, we present a material system with two ferrimagnetic GdxFe100-x layers where the relative orientation of the Fe magnetic moments can be set by temperature in the presence of an external magnetic field. We demonstrate that, depending on the relative alignment of the Fe moments, the spintronic emitter system can be either in a high- or in a low-amplitude terahertz emitting state. Nonmagnetic metal layers with opposite spin Hall angles were utilized for further improvement of the efficiency. This study opens a route for an efficient type of spintronic terahertz emitter system based on the ferrimagnetic properties of rare earth-3d transition metal alloys, which allows switching the emission state from high to low power.
New approach to an underwater discharge simulation using elliptic coordinates
Authors: Stelmashuk Vitaliy
Published: January 2020

In this study, a system of two equations is developed that allows the time evolution of the underwater spark channel to be calculated numerically from a given power input. The proposed mathematical model utilizes the elliptical coordinates. This approach has the advantage of considering the underwater spark as an expanding ellipsoid, which closely corresponds to experimental observations. Similar to spherical or cylindrical models, the proposed method considers only one spatial coordinate as a function of time, which simplifies the analysis. The predictions of this model are compared with the experimental results.
Strong coupling between magnetic resonance and propagating surface plasmons at visible light frequencies
Authors: Wang Jingyu , Yang Weimin , Radjenovic Petar M. , He Yonglin , Yang Zhilin , Li Jian-Feng
Published: January 2020

Light-matter interactions in nanostructures have shown great potential in physics, chemistry, surface science, materials science, and nanophotonics. Herein, for the first time, the feasibility of strong coupling between plasmon-induced magnetic resonant and propagating surface plasmonic modes at visible light frequencies is theoretically demonstrated. Taking advantage of the strong coupling between these modes allowed for a narrow-linewidth hybrid mode with a huge electromagnetic field enhancement to be acquired. This work can serve as a promising guide for designing a platform with strong coupling based on magnetic resonance at visible and even ultraviolet light frequencies and also offers an avenue for further exploration of strong light-matter interactions at the nanoscale.
Li2S growth on graphene: Impact on the electrochemical performance of Li-S batteries
Authors: Longo Roberto C. , Camacho-Forero Luis E. , Balbuena Perla B.
Published: January 2020

Lithium-sulfur batteries show remarkable potential for energy storage applications due to their high-specific capacity and the low cost of active materials, especially sulfur. However, whereas there is a consensus about the use of lithium metal as the negative electrode, there is not a clear and widely accepted architectural design for the positive electrode of sulfur batteries. The difficulties arise when trying to find a balance between high-surface-area architectures and practical utilization of the sulfur content. Intensive understanding of the interfacial mechanisms becomes then crucial to design optimized carbon-hosted sulfur architectures with enhanced electrochemical performance. In this work, we use density functional theory (DFT)-based first principles calculations to describe and characterize the growing mechanisms of Li2S active material on graphene, taken as an example of a nonencapsulated carbon host for the positive electrode of Li-S batteries. We first unravel the two growing mechanisms of Li2S supported nanostructures, which explain recent experimental findings on real-time monitoring of interfacial deposition of lithium sulfides during discharge, obtained by means of in situ atomic force microscopy. Then, using a combination of mathematical tools and DFT calculations, we obtain the first cycle voltage plot, explaining the three different regions observed that ultimately lead to the formation of high-order polysulfides upon charge. Finally, we show how the different Li2S supported nanostructures can be characterized in X-ray photoelectron spectroscopy measurements. Altogether, this work provides useful insights for the rational design of new carbon-hosted sulfur architectures with optimized characteristics for the positive electrode of lithium-sulfur batteries.
Analysis of the Fe 2p XPS for hematite α Fe2O3: Consequences of covalent bonding and orbital splittings on multiplet splittings
Authors: Bagus Paul S. , Nelin Connie J. , Brundle C. R. , Lahiri N. , Ilton Eugene S. , Rosso Kevin M.
Published: January 2020

The origins of the complex Fe 2p X-Ray Photoelectron Spectra (XPS) of hematite (α-Fe2O3) are analyzed and related to the character of the bonding in this compound. This analysis provides a new and novel view of the reasons for XPS binding energies (BEs) and BE shifts, which deepens the current understanding and interpretation of the physical and chemical significance of the XPS. In particular, many-body effects are considered for the initial and the final, 2p-hole configuration wavefunctions. It is shown that a one-body or one-configuration analysis is not sufficient and that the many-body, many-determinantal, and many-configurational character of the wavefunctions must be taken into account to describe and understand why the XPS intensity is spread over an extremely large number of final 2p-hole multiplets. The focus is on the consequences of angular momentum coupling of the core and valence open shell electrons, the ligand field splittings of the valence shell orbitals, and the degree of covalent mixing of the Fe(3d) electrons with the O(2p) electrons. Novel theoretical methods are used to estimate the importance of these various terms. An important consequence of covalency is a reduction in the energy separation of the multiplets. Although shake satellites are not considered explicitly, the total losses of intensity from the angular momentum multiplets to shake satellites is determined and related to the covalent character of the Fe-O interaction. The losses are found to be the same for Fe 2p1/2 and 2p3/2 ionization.
Using Molecular Modelling to Understand and Predict the Impact of Organic Additives as Crystal Growth Modifiers
Authors: Jones Franca , Rohl Andrew L.
Published: January 2020

Empirical molecular modelling was used to investigate the impact of organic additives on crystal morphology and inhibition. The replacement energy was found to correlate reasonably well with the degree of inhibition as determined from conductivity data. The replacement energy was also able to predict the barium sulfate face on which additive adsorption was most likely. While the ability of the organic functional groups to sit in the vacant sulfate lattice positions (the so-called ‘lattice matching’ criteria) appears intuitively sensible, it was found that this is not a sufficient criterion to predict real behaviour. A better criterion is the overall replacement energy as it takes into consideration the number of Ba–Oorganic interactions and whether the adsorption process overall is energetically favourable (by including the hydration energy of the ions). Thus, the replacement energy can successfully predict the effect of organic molecules on the crystal growth modification of barium sulfate.
Carbon monoxide in the process of uncontrolled combustion - occurrence, hazards and first aid
Authors: Majstorović A , Babić V , Todić M
Published: January 2020

Carbon monoxide (CO) is a highly toxic gas, odorless and tasteless, belongs to the group of flammable and explosive gases, and is produced by incomplete combustion of fossil fuels in power plants, automobiles, households and various industrial processes. It is very active in chemistry, reacts with many metals, sulfur, chlorine, etc.

As it is flammable and explosive gas, it is a significant risk of its ignition if found near an open flame. Carbon dioxide, dry chemical or water is used for quenching, [1].

The concentration of 1 % carbon monoxide in the air is lethal. Carbon monoxide is toxic and indirectly contributes to global warming as a precursor to ozone. Carbon monoxide emissions from the atmosphere come from a number of sources, most of all traffic.The introduction of catalytic converters, and especially diesel vehicles, has significantly reduced carbon monoxide emissions in the EU and in countries in transition.
Influence of the thickness of the Tungsten Carbide (WC) coating deposited on martensitic stainless steel on corrosion resistance
Authors: Benea M L , Benea L P
Published: January 2020

On the martensitic non-corrosive steel support (Z12CNDV12) it is deposited by plasma jet, tungsten carbide, in three different thicknesses. We determined the electrochemical potential of both the coating layer and the substrate for different concentrations of NaCl in a solution. The experimental results are mathematically processed. From each protective coating a 1, 2 and 3 degree polynomial fit were obtained. Also, the comparison between the three obtained thicknesses mathematical function is realized.
Modification of the average durability for CuSn12 bronze at cavitation erosion using volumetric treatments
Authors: Lazar I , Bordeasu I , Popoviciu M O , Hluscu M , Podoleanu C E , Duma S T , Pirvulescu L D , Sava M
Published: January 2020

The bronze CuSn is used sometimes for equipment components working in cavitation conditions, as for example ship propellers, bodies and other parts of valves. To increase the working time, in cavitation conditions, those elements can be subjected to volumetric thermal treatments. The present research is concerned with the increase of the mean durability

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¯

c
a
v

, of the bronze CuSn12 by applying two volume treatments: quenching both at 700°C and 800°C, with tempering at 500°C. The cavitation erosion behavior was experimentally tested using the standard vibratory device of the Cavitation Laboratory of Timisoara Polytechnic University. Comparing the results we found that the durability, in both cases, is substantial increased, the better solution being the quenching with the lower temperature.
Mining exploitation forecasted effects caused by a hard coal extraction from a thick seam
Authors: Orwat J
Published: January 2020

Paper describes an example of underground mining exploitation which in a thick seam divided into a few layers has been conducted. It took place in the years 2013 – 2018 in the southern part of Poland, in the Upper Silesian Coal Basin and was carried out by the use of four, high longwalls with a roof rocks cave-in. In article a reprognosis of the mining exploitation impacts on a terrain surface has been done. For this purpose the EDN – OPN computer program was used. Extraction influences by the use of the Bialek’s formula for subsidence have been predicted. There the subsidence, inclinations and horizontal strains after the end of every exploitation stage have been calculated. Thanks to that it is possible to determine the expected range and size of exploitation impacts on a terrain surface and the objects located on it.
About the calculus of the relative frequency shifts for a beam with multiple cracks
Authors: Gillich G R , Nedelcu D , Hamat C O , Wahab M Abdel , Barbinta C I
Published: January 2020

We propose in this paper a mathematical relationship to calculate the natural frequency shifts of beams due to multiple cracks. The relationship is based on the application of the superposition principle. A crack alters the frequencies for the bending vibration modes in a particular manner, with respect to the crack depth and location. We have shown that the affected beam have the same natural frequencies as a healthy beam with a smaller thickness; this thickness has to be calculated separately for each vibration mode. As a consequence, we can consider the next crack affects healthy beams, one different beam for each considered mode. Subsequent cracks affect a bigger number of beams. For the last crack, we have to calculate the frequencies for a number of beams that is the number of the considered vibration modes to the power equal with the number of cracks. To automate the process of calculating the resulted natural frequencies, we have written a program in Visual Basic for Excel Applications (VBEA), which permits finding the natural frequencies of a beam with up to nine cracks. This application can calculate the natural frequencies for four beam types: with fixed-free, fixed-fixed, simply supported and free-free restraints. The results obtained by calculating the frequencies for several damage scenarios and boundary conditions fit those obtained from simulations by involving the finite element method.
Optimal and stable energetic operation of wind power systems at variable wind speed
Authors: Chioncel C P , Murarescu C , Dudu M , Tirian O G
Published: January 2020

In the present paper we analyse the stable and optimal operation of wind power systems, WPS, composed of wind turbines, TV, coupled with synchronous generators with permanent magnets (SGPM), high power SGPM in the Dobrogea area, 4MW turbines manufactured at General Electric. Based on the experimental data, the wind turbine models MM-WT and the MM-SGPM permanent magnet synchronous generator are determined. Using these mathematical models, simulations are made of rapid variations in wind speed over time and the conditions for stable and energy-efficient EEA operation are highlighted. It mainly analyses the evolutions in time of power and speed from the generator, in direct connection with the change in wind speed over time. At the end of the paper is given a power calculation algorithm at SGPM, based on wind velocity measurements and VUM, ω, so that the operation is stable and energy optimal.
Influence of meteorological factors on modelling the thermal regime of a river
Authors: Neagoe A , Tică E I , Ahmad-Rashid K , Popa F , Popa B
Published: January 2020

The aim of the paper is to determine whether the use of several parameters in a multi-linear regression equation can estimate the evolution of the water temperature. Thus, a simplified physical-based non-spatial model is designed for calculating the time variation of river water temperature. The water-to-air transfer function is constructed using the recorded environmental factors, instead the flow rate, respectively the depth of water in the riverbed, is assumed to be constant over the 31-days analysis period. A comparison between logistic relation, according to a classical proposed model and multiple linear regression with four parameters is done.
Impact of the ecological flow of some small hydropower plants on their energy production in Romania
Authors: Popa F , Dumitran G E , Vuta L I , Tica E I , Popa B , Neagoe A
Published: January 2020

In this paper, for 24 SHPPs with significant installed capacity, between 676 and 6430 kW, totalizing almost 76 MW, with installed flows between 1.3 and 80 m3/s, the energy production is evaluated without and with an ecological flow representing 35 to 4.6 % from the mean flow in SHPP intake cross section. The energy loss is evaluated and there are presented some conclusions and assumptions regarding the way to impose an increased ecological flow without affecting too much the green energy produced in SHPPs.
Fuzzy Logic Based Approach for Possibility of Road Accidents
Authors: Upadhya S Mamatha , Vinothina V
Published: January 2020

Deaths and injuries occurring from road accidents remain severe issue globally. Currently, it is estimated by the World Health Organization that deaths from road accident have increased to 1.35 million a year. This shows closely 3700 people are dying on the world’s roads each day, every year 50 millions are disabled or injured. These fatalities take a massive toll on families as well as on communities. Some of the reasons for this increase in road accidents are rapid urbanization, lack of enforcement, poor safety standards, people driving fatigued or distracted, influence of alcohol, drugs, speeding, failure to wear helmets, seat-belts etc. The fact is every one of these deaths as well as injuries can be preventable by enforcing operational measures such as safety standards for vehicles and roads. Hence, this paper analyzes the possibility of road accident for different distraction parameters.
Optimizing sowing window and cultivar choice can boost China’s maize yield under 1.5 °C and 2 °C global warming
Authors: Huang Mingxia , Wang Jing , Wang Bin , Liu De Li , Yu Qiang , He Di , Wang Na , Pan Xuebiao
Published: January 2020

Climate change, with increased temperatures and varied rainfall, poses a great challenge to food security around the world. Appropriately assessing the impacts of climate change on crop productivity and understanding the adaptation potential of agriculture to climate change are urgently needed to help develop effective strategies for future agriculture and to maintain food security. In this study, we studied future maize yield changes under 1.5 °C (2018–2037) and 2 °C (2044–2063) warming scenarios and investigated the adaptation potential across China’s Maize Belt by optimizing the sowing date and cultivar using the APSIM-Maize model. In comparison to the baseline scenario, under the 1.5 °C and 2 °C warming scenarios, we found that without adaptation, maize yields would increase in the relatively cool regions with a single-cropping system but decrease in other regions. However, in comparison with the baseline scenario, under the 1.5 °C and 2 °C warming scenarios with adaptation, maize yields would increase by 11.1%–53.9% across the study area. Across the maize belt, compared with the baseline scenario, under warming of 1.5 °C, the potential sowing window would increase by 2–17 d, and under warming of 2 °C, this sowing window would increase by 4–26 d. The optimal sowing window would also be significantly extended in the regions with single-cropping systems by an average of 10 d under the 1.5 °C warming scenario and 12 d under the 2 °C warming scenario. Late-maturing cultivar achieved higher yield than early-middle maturing cultivars in all regions except the north part of Northeast China. Adjusting the sowing date by increasing growth-period precipitation contributed more (44.5%–96.7%) to yield improvements than shifting cultivars (0%–50.8%) and climate change (−53.1% to 23.0%) across all maize planting regions except in the wet southwestern parts of the maize belt. The differences among the maize planting regions in terms of high adaptation potential provide invaluable information for policymakers and stakeholders of maize production to set out optimized agricultural strategies to safeguard the supply of maize.
Regenerating the Identity in Historic Waterfront: A Case Study of Central Market Waterfront, Kuala Lumpur
Authors: Iqbal T , Rani W N M W M , Wahab M H
Published: January 2020

The study focused on assessing the attributes of identity in the historic waterfront to regenerate the historic waterfront with eroding identity. Kuala Lumpur, the capital city of Malaysia, is succumbed by unprecedented urbanization in the past few decades. Thus, Sungai Klang and Sungai Gombak are overshadowed by new developments which are insensitive to the existing character and setting of the historic waterfronts. Consequently, this threatens the historic waterfront identity, even though the rivers were the starting point of Kuala Lumpur. This study aimed at assessing the factors to regenerate the identity in the historic waterfront and propose strategies that can contribute to the regeneration of identity of the area. The research methodology adopted is qualitative approach. Attributes that contribute to the identity of the historic waterfront were identified through literature review and evaluated by townscape appraisal and field observation. The area selected as the case study is the Central Market area at the historic Klang waterfront. Central Market is a Category Two Heritage building separated from water edge by the new LRT infrastructure. Historically the former wet market, Jalan Benteng and the water body created a combined genius loci for the place, as boats carried goods to and from the Central Market, forming a significant node. Key findings indicated that several attributes of identity are eroding, causing poor accessibility and legibility, poor water quality and no block permeability to extend activities. Also, the new landscape elements by ROL Project at Jalan Benteng affect the enclosure of the historic waterfront promenade. The natural and man-made landscape elements surrounding the waterfront are not coherent, does not aid in legibility to the waterfront but rather affect the meaning and association with the historic setting. The open spaces in the waterfront precinct are misused, such as the car park of Central Market, which has immense potential to be a major node. These scenarios are deteriorating the identity of the historic waterfront. Finally, the study proposed several urban design recommendations aimed at regenerating the identity in the historic waterfront.
The Removal of Organic Materials and Nutrients with Addition of Artificial Supporting Materials in The Water Body (A Case Study of Cikapayang River, Bandung City Hall)
Authors: Prayogo W , Soewondo P , Zakiyya N M , Putri D W , Muntalif B S
Published: January 2020

Cikapayang River is a branch from Citarum River that flows across Bandung City, starting from Dago to Riau Street. Ninety percent of the community living around the river dispose of domestic wastewater directly into a water body without any treatment. This condition causes a decline in river quality. Various technological efforts have been made to enhance the water quality in the river, including efforts in dealing with pollution prevention from the source treatment in the water body. One of the technical options in providing therapy in the water body is using the filtration with supporting materials. It is hoped that through this supporting material, physical, chemical, and biological processes will occur, so that organic material and nutrients can be eliminated. In this study, removal of organic materials and nutrients was carried out by using artificial supporting materials in Cikapayang River with two different sizes, Block I is 350x15x100 cm, and Block II is 325x15x100 cm. Cikapayang River quality is classified as lightly pollute based on PI calculation. The average removal efficiency of Block I is 50% COD, 33% TSS, 23% TP, and 39% TN, meanwhile Block II has a removal efficiency of 38% COD, 30% TSS, 28% TP, and 49% TN. The difference in material surface area between the two materials causes different removal efficiency. But these results indicate that the content can be used to remove organic materials and nutrients. The addition of artificial support material in Cikapayang River can reduce IP value, from 4.74 to 3.71.
The Awareness Level of Building Owners to Conserve Cultural Heritage Area in Kotagede, Yogyakarta
Authors: Dharmasanti R , Dewi S P
Published: January 2020

The concept of cultural heritage conservation is not only about architecture but also about people / communities who are related to cultural heritage. The local community is one of the actors who play a role in the conservation of cultural heritage areas. There are 41,7% of Kotagede's old buildings that are not maintained, damaged, and extinct. Building changes were carried out by the owner itself. Therefore, it is important to identify the level of awareness of old building owners to conserving the Kotagede area. The research method used quantitative research. The respondents in this study were the owners of the old building Kotagede. The research data were collected using a questionnaire and observation. The likert scale aims to determine the level of awareness of building owners. The results of this study indicate that the condition of building owners can affect the conservation awareness of building owners. The limited conservation information causes the owners to change the old buildings. The problem of building heritage causes owners to have doubts about the sense of ownership of old buildings. The building owners, who have a medium and low economic level, feel unable to spend on building maintenance costs. The old building was located near the modern environment so that the owners became affected, breaking the government rules, and cared less so that the authenticity of the old building forms became reduced. The conclusion of this study shows that the awareness of the owners' buildings is still at a doubt level. It means that actually, the owners already understand that it is significant to conserve their old buildings. However, they have not been able to do it optimally because there are still obstacles that hinder them.
The Position and Function of Masjid Jami’ and City Square in The Dynamics of Pekalongan Development
Authors: Astuti S P , Ulya I
Published: January 2020

Identical to other cities in Java, Pekalongan city center is characterized by the presence of city square (alun-alun). Pendopo (palace/central government) - alun-alun (city square) – mosque are characteristic features of the Islamic Mataram city. Commonly, the square as the heart of the city is located in the middle, it is surrounded by the Jami mosque at west side of the square, the pendopo/governance office at the south side of the square, plaza at the east side of square, and settlement at the north side of square . Nowadays, the position of the pendopo in Pekalongan still remained as the beginning of its existence, but there is a change of its function especially in the square and the pendopo. The pendopo that was previously the office and official residence of the Pekalongan Regent no longer functions as before since the government of Pekalongan Regency was moved to Kajen in 2003. Furthermore, slowly but surely, the city square was switched its dominant role as an economic function, that is surrounded by stalls, culinary and fashion products sellers started from afternoon to the middle of night. In addition to the reason for the movement of the central government of Pekalongan Regency from this place to Kajen, this also happened because it was built the center of the Pekalongan city government buildings in other area (Mataram street) that is supported with the square. Therefore, a research on the position and function of Jami’ mosque and city square needs to be held, considering that in this case there were time dimensions and historical values that must be preserved in the context of urban development. This study uses a phenomenological approach. The findings of this study are the existence of Jami mosque is timeless, meanwhile the city square is needed to be revitalized so that it has functions in accordance with its era without leaving its function as a safe and comfortable public open space and having continuity with the function of the mosque.
The Distinctiveness of Plant Characteristic in Reinforcing the Place Identity for Royal Town of Kuala Kangsar, Perak
Authors: Khalid I K M , Tahir O M , Ismail N A , Muslim Z
Published: January 2020

Plants are a valuable indicator for aesthetic-visual probity in order to manifest the type and degree of the human-nature relationship over time. The study aims to identify the distinctiveness of plant characteristics in order to reinforce townscape elements in establishing the place identity for the case study of the Royal Town of Kuala Kangsar, Perak. The study methodology involved a semi-structured interview, with purposive sampling in three categories, which is professionals, policymaker, and skilled practitioner. The results show that there is a significance between the royal plants and the distinctiveness of traditional plants which are intended to be the townscape element’s identity of the royal town of Kuala Kangsar, Perak. The findings of the study are expected to assist the city council in their town planning by proposing the plants’ character images or the identity of the royal town of Kuala Kangsar. Besides, the findings could apply a guideline for future developments in the Royal Town of Kuala Kangsar, Perak.
Resiliency of Prembaen as a Market Kampong in Inner City of Semarang
Authors: Kurniawati W , Dewi D I K , Nurini  , Rahmat R R B
Published: January 2020

The intensification of commercial activities in the triangle area along the Pemuda, Pandanaran, and Gajahmada roads in Semarang City changed land use along the main roads and resulted in a spatial, economic, and socio-cultural transformation of the community inside the area. Based on history, the kampong behind the three main streets are old kampong, including Prembaen. Prembaen, a market kampong, is facing with migration, and spatial use activities conversion. This market kampong has persisted more than 50 years and created a mutualism symbiosis between residents and migrant sellers. Although it is surrounded by giant economic activities on the main roads, the kampong and its market are resilient and continued. For this reason, research on the market kampong sustainability is significant to determine the survival of the downtown neighbourhood. The main objective of this study is to describe the Role of Prambaen Market in the golden triangle area of Semarang, to identify social interactions in the Prambaen Market, analyze the resilience of the Prambaen Market, and identify spatial sustainability in the Prambaen Market. This research tries to conduct qualitative methods to capture phenomena in selected locations. This research needs to understand the situation that remains of the downtown environment in the face of large economic forces. The results of the study show that the Prembaen Market has historical strength as well as the potential of tangible local wisdom of economic activity manifested in the daily lives of the community. The strategy to achieve Prembaen market resilience is the social interaction between traders, visitors, and residents to continue to maintain and strengthen the joint activities of Prambaen Market activities. In addition, the morphology of the Prambaen Market area is still maintained, which has not changed since long ago in the urgency of the surrounding commercial / industrial offices.
Spatial Expression of Malay Kampung Semarang in Facing Flood Disaster
Authors: Kurniawati W , Mussadun  , Nugraha M F
Published: January 2020

Disaster is one of the most significant global challenges confronting the society and environment in recent days. It poses a threat to the cultural heritage of conservation areas, including Malay Kampung (Kampung Melayu) Semarang. Today, it is experiencing physical, social and economic degradation, triggered by environmental factors and disasters such as flooding. This research therefore aims to identify the areas of residual disasters and monitor its impact on spatial expression and the resilience patterns. New adaptation and spatial expression develop when there is prolonged contact between flood disaster and the environment. Hence, a spatial expression transformation due to disaster adaptation occurs this expression is a type of resiliency pattern vulnerable in the area. During flood disasters, this pattern is essential to observe and understand the resiliency along with the sustainability of the cultural heritage of these affected areas. This research used qualitative method, Descriptive analysis technique conducted in this study to determining the research area delineation, identifying phenomena of flood disasters in Malay Kampung Semarang, analyzing spatial expression of Malay Kampung Semarang, and determining flood effects on spatial expression. Banjar Kampung was then chosen to represent the entire Semarang Malay Kampung. The spatial expression affected the building conditions, resulting in damage to some inhabited and non-inhabited buildings though some were not severely affected (are in good condition), and however, the buildings can be renovated. Out of the 57 buildings, in the region, 41 are in good condition and 16 others are in damaged condition. The result obtained from the study indicated that the flood phenomenon that occurred is now improved. The occurrence, depth, affected areas and duration of flood has improved as shown in this study.
Effectiveness of Strategic Environmental Studies in Supporting Sustainable Development Goals
Authors: Aryani R V
Published: January 2020

Abctract

Development is the process of optimizing all the resources for specific purposes and objectives so that it can be expected that all activities to be carried out by the community will be achieved. The problem is, development often causes a decrease in the quality of the environment resulting an environmental problems. The concept of Sustainable Development is a major concern in various development planning and implementation processes. With sustainable development, development is expected to have a minimum impact on the occurrence of environmental damage. Strategic Environmental Assessment is a study that evaluate policies, plans and programs contained in spatial plans and development plans. The purpose of this study is to identify the effectiveness of strategic environmental assessment activities in supporting sustainable development in Sumbawa Regency. This study uses a descriptive qualitative method by examining the substance of the strategic environmental assessment in Sumbawa Regency. The type of data obtained is primary data obtained from the results of focus group discussions with the community and related agencies. The results of the research are that the strategic environmental study has been quite effective in assessing the negative impacts of a policy, plan and program on the environment, but has not been effective in solving the problem of sustainable development.
The influence of earthquake force directions on building construction in Lombok Island: a case study of Pandanduri dam in East Lombok
Authors: Afrizal F , Agustawijaya D S , Lestari A
Published: January 2020

Lombok Island is one of the regions in Indonesia that has a relatively high risk of earthquakes due to being flanked by two earthquake sources, namely from the south in the form of Indo-Australian plate thrusting (subduction mega-thrust) and north there is a north arc pressure (Flores thrust). Pandanduri Dam is located in the direction of the earthquake force N 171° E. This study aims to determine changes in dam planning using earthquake force calculations from SNI 1726-2002 to SNI 1726-2012 and the effect of the direction of earthquake strength on dam stability. The analysis results show that earthquake risk in Lombok Island is 0.34 g and 0.42 g for the possibility of exceeding 10% and 2% in 50 years. SNI changes in earthquake force calculations have decreased by 26% for 500 years and an increase of 10% for 2500 years. The percentage of the earthquake force directions is not known to be greater than the percentage the earthquake force directions known that N 171°E is influenced by the angle produced by the earthquake direction N 171° E which is 0.094° for the main force direction of the dam and 89,906° for the direction perpendicular to the dam.
The impact of tailings flow on the abundance of deep-sea meiofauna in Sumbawa waters
Authors: Susetiono  , Witasari Y , Prayogo W , Yusuf M S , Waworuntu J
Published: January 2020

The potential effect of the mining activity in Batu Hijau, Sumbawa, Indonesia, is a by-product called tailings. Before being discharged into the sea, the tailings have been carefully processed on land, so that do not contain chemical elements that are harmful to living resources. The tailing slurry flowing with velocity of 5.7 – 6.4 meters/second at the opening of pipeline and 0.5 – 1.0 meter/second along the seabed, and finally come to rest at a depth of 3,000 – 4,000 meters. From forty sediment sampled was observed that six sampling sites were not found any meiofauna, whereas other sites meiofauna found with varied taxa diversity and its abundance. From the analysis on relationship between meiofauna abundance and the percentage of tailings it can be concluded that high percentage of tailings greatly influences the taxa diversity and meiofauna abundance in sediments. However, besides the presence of tailing as mentioned above, physical instability of the sediment as the impact of tailings flow is highly influential to the meiofauna community.
High pressure acid leaching: a newly introduced technology in Indonesia
Authors: Gultom T , Sianipar A
Published: January 2020

PT Halmahera Persada Lygend (PTHPL) plans to construct new technology for nickel laterite ore processing in Obi Island, North Maluku Province. The facility is expected to produce 247,000 tonnes of NiSO4.7H2O and 32,000 tonnes of CoSO4.7H2O to be sold for the raw material of electric vehicle battery. Indonesia is one of world largest nickel laterite resources and currently only nickel ore saprolite has been exploited while nickel limonite is abandoned as waste due to the lack of technology. In the last decade, nickel smelter is booming in Indonesia to process nickel saprolite to become Ferro Nickel, Nickel Pig Iron, Nickel Matte. This study is aimed to assess the potential implementation of High-Pressure Acid Leaching (HPAL). HPAL is a proven technology but not utilized in Indonesia due to the high investment, and it requires a large media for waste disposal. Nickel limonite ore with grade 1.1 – 1.4 % can be processed using HPAL technology to produce more than 37% nickel and another beneficial product, which is cobalt. Nickel world demand shifts to support electric vehicle battery even though stainless steel demand is still high. The Government of Indonesia is currently starting to support the electric vehicle market program. Therefore HPAL project in Indonesia is a high opportunity and a good investment for investors.