bluuebunny/crossref_metadata_2025 huggingface dataset:
Trade Rules for the Digital Economy: Charting New Waters at the WTO
Authors: NEERAJ R. S.
Published: January 2019

This Article attempts to explore the challenges in situating a multilateral digital trade agreement within the legal framework of the World Trade Organization (WTO). Section 1 of the article discusses the broad challenges that digitization poses for the international legal framework for trade regulation. I argue first that the traditional classification of products into goods and services under the WTO system is structurally incompatible with the digital economy. I also argue that striking the appropriate balance between trade liberalization and the pursuit of legitimate public policy objectives in a digital trade agreement will be uniquely challenging because certain features that are intrinsic to the digital industry and business strategies of established players in the digital market raise serious anticompetition challenges. A multilateral agreement regulating digital trade needs to acknowledge and address these challenges. Section 2 surveys the efforts that have been undertaken to regulate digital trade as manifested in the WTO Work Program on Electronic Commerce. Acknowledging that the digital trade agenda of the Trans-Pacific Partnership (TPP) agreement could be used as a benchmark for discussions on e-commerce at the WTO, I argue that future negotiations for a multilateral digital trade policy will not benefit from using the TPP's digital trade agenda as a benchmark. The TPP does not reconcile systemic tensions between the digital economy and the extant WTO system or address the anticompetition challenges that are unique to the digital ecosystem.
Beware of Inertial Instability Masquerading as Gravity Waves in Stratospheric Temperature Perturbations
Authors: Harvey V. Lynn , Knox John A.
Published: January 2019

Rapp, Dörnbrack, and Preusse (2018, https://doi.org/10.1029/2018GL079142) uses radio occultation observations and meteorological data from the European Centre for Medium Range Weather Forecasting to quantify the effect of inertial instability on stratospheric temperature variability. A very interesting by‐product of their study is the take‐away message that inertial instability “pancake structures” may be misidentified as being caused by gravity waves. We place this result in the context of inertial instability research. We concur with Rapp et al.'s caution to researchers to first examine the large‐scale meteorological environment to rule out inertial instability when analyzing temperature fluctuations that appear to be gravity wave signals in vertical profile data.
On the Close Correspondence Between Storm Time ULF Wave Power and the POES VLF Chorus Wave Amplitude Proxy
Authors: Dimitrakoudis Stavros , Mann Ian R.
Published: January 2019

Ground‐based Pc5 ultralow frequency (ULF) wave power in multiple ground‐based meridians is compared to the very low frequency (VLF) wave amplitude proxy, derived from Polar Operational Environmental Satellite (POES) precipitation, for the 33 storms studied by Li et al. (2015, https://doi.org/10.1002/2015GL065342). The results reveal common L‐shell and time profiles for the ULF waves and VLF proxy for every single storm, especially at L ≤ 6, and identical discrimination between efficient and inefficient radiation belt electron acceleration. The observations imply either ULF waves play a role in driving precipitation, which is falsely interpreted as VLF wave power in the proxy, ULF waves drive VLF waves (the reverse being energetically unfeasible), or both have a common driver with nearly identical L‐shell and time dependence. Global ground‐based ULF wave power coherence implies that a small number of meridians can be used to estimate storm time radial diffusion coefficients. However, the strong correspondence between ULF wave power and VLF wave proxy complicates causative assessments of electron acceleration.
Leukemic transformation among 1306 patients with primary myelofibrosis: risk factors and development of a predictive model
Authors: Vallapureddy Rangit R. , Mudireddy Mythri , Penna Domenico , Lasho Terra L. , Finke Christy M. , Hanson Curtis A. , Ketterling Rhett P. , Begna Kebede H. , Gangat Naseema , Pardanani Animesh , Tefferi Ayalew
Published: January 2019

Among 1306 patients with primary myelofibrosis (PMF), we sought to identify risk factors that predicted leukemic transformation (LT) in the first 5 years of disease and also over the course of the disease. 149 (11%) LT were documented; patients who subsequently developed LT (n = 149), compared to those who remained in chronic phase disease (n = 1,157), were more likely to be males (p = 0.02) and display higher circulating blasts (p = 0.03), ASXL1 (p = 0.01), SRSF2 (p = 0.001) and IDH1 (p = 0.02) mutations. Logistic regression analysis identified IDH1, ASXL1 and SRSF2 mutations, very high-risk karyotype, age > 70 years, male sex, circulating blasts ≥ 3%, presence of moderate or severe anemia and constitutional symptoms, as predictors of LT in the first 5 years of diagnosis. Time-to-event Cox analysis confirmed LT prediction for IDH1 mutation (HR 4.3), circulating blasts ≥ 3% (HR 3.3), SRSF2 mutation (HR 3.0), age > 70 years (HR 2.1), ASXL1 mutation (HR 2.0) and presence of moderate or severe anemia (HR 1.9). HR-based risk point allocation resulted in a three-tiered LT risk model: high-risk (LT incidence 57%; HR 39.3, 95% CI 10.8–114), intermediate-risk (LT incidence 17%; HR 4.1, 95% CI 2.4–7.3) and low-risk (LT incidence 8%). The current study provides a highly discriminating LT predictive model for PMF.
The association between genetic variants of angiopoietin-like 3 and risk of diabetes mellitus is modified by dietary factors in Koreans
Authors: Park Clara Yongjoo , Moon Jiyoung , Jo Garam , Lee Juhee , Kim Oh Yoen , Oh Hannah , Lim Hyunjung , Shin Min-Jeong
Published: January 2019

The role of angiopoietin-like 3 (ANGPTL3) in blood lipid levels, cardiovascular disease risk, and glucose metabolism has received wide attention. This study aimed to examine whether rs11207997 in ANGPTL3 is associated with a 10-year risk of diabetes mellitus (DM) and if the association is modified by the consumption of certain food groups or nutrients. A prospective cohort study was designed using the Ansan–Ansung data of the Korean Genome and Epidemiology Study (n = 7,358; age ≥40 years at baseline). Participants with the T allele of rs11207997, particularly TT homozygotes, had lower triglyceride (TG) and total cholesterol levels than those with CC. There was no association with fasting blood glucose or other biochemical parameters. ANGPTL3 mRNA was positively associated with circulating TG levels and blood pressure (all p < 0.05). Cox proportional hazard models showed that the rs11207997 T allele is associated with a lower risk of DM after adjusting for covariates (hazard ratio: 0.90, 95% confidence interval: 0.812–0.998, p = 0.046). Furthermore, the association between rs11207997 and the risk of DM was modified by dietary factors. These associations were no longer statistically significant when additionally adjusted for baseline TG, a potential mediator. Our data suggest that genetic variation of rs11207997 in the ANGPTL3 gene is associated with risk of DM, possibly through contributing to a lifelong set point of TG.
Peptide-grafted dextran vectors for efficient and high-loading gene delivery
Authors: Hu Yang , Wang Huifeng , Song Haiqing , Young Megan , Fan Yaqian , Xu Fu-Jian , Qu Xinjian , Lei Xia , Liu Ying , Cheng Gang
Published: January 2019

Among various polymeric gene delivery systems, peptide-based vectors demonstrate great potential owing to their unique structure and properties, including flexibility; however, there is insufficient molecular understanding of the role and properties of amino acids as building blocks in gene delivery.
Synthesis of 9-borafluorene analogues featuring a three-dimensional 1,1′-bis(o-carborane) backbone
Authors: Yruegas Sam , Axtell Jonathan C. , Kirlikovali Kent O. , Spokoyny Alexander M. , Martin Caleb D.
Published: January 2019

The synthesis of [1,1′-bis(o-carboranyl)]boranes was achieved through the deprotonation of 1,1′-bis(o-carborane) reagents followed by salt metathesis with (iPr)2NBCl2.
Molecular engineering of polymeric supra-amphiphiles
Authors: Chang Yincheng , Jiao Yang , Symons Henry E. , Xu Jiang-Fei , Faul Charl F. J. , Zhang Xi
Published: January 2019

Polymeric supra-amphiphiles are amphiphiles that are fabricated by linking polymeric segments, or small molecules and polymeric segments, by noncovalent interactions or dynamic covalent bonds.
Novel ternary transition metal oxide solid solution: mesoporous Ni–Mn–Co–O nanowire arrays as an integrated anode for high-power lithium-ion batteries
Authors: Zhou Junxiang , Li Donglin , Han Jiaxing , Fan Xiaoyong
Published: January 2019

Mesoporous Ni–Mn–Co–O ternary solid solution nanowire arrays grown on Cu substrates as integrated anodes for high-power lithium-ion batteries.
Usingparahydrogen induced polarization to study steps in the hydroformylation reaction
Authors: Guan Dexin , Godard Cyril , Polas Stacey M. , Tooze Robert P. , Whitwood Adrian C. , Duckett Simon B.
Published: January 2019

Para-hydrogen assisted NMR spectroscopy allows the detection of an array of reaction intermediates during iridium catalyzed hydroformylation.
One-dimensional magnetic chain composed of CuII and polychlorinated dipyridylphenylmethyl radical: temperature-dependent Jahn–Teller distortion correlated to π-conjugation and magnetic properties
Authors: Kimura Shun , Uchida Hikaru , Kusamoto Tetsuro , Nishihara Hiroshi
Published: January 2019

The Jahn–Teller distortion, π-conjugation mode, and magnetic properties were coupled in the ferromagnetic CuII-radical chain, resulting in unique properties.
Synthesis, characterisation, molecular docking, biomolecular interaction and cytotoxicity studies of novel ruthenium(ii)–arene-2-heteroarylbenzoxazole complexes
Authors: De Sourav , Chaudhuri Shreya Ray , Panda Arpita , Jadhav Gajanan Rahosaheb , Kumar R. Selva , Manohar Prasanth , Ramesh N. , Mondal Ashaparna , Moorthy Anbalagan , Banerjee Subhasis , Paira Priyankar , Kumar S. K. Ashok
Published: January 2019

Ru(ii)–arene-2-heteroarylbenzoxazole complexes were synthesized and implemented for their biological evaluation.
Mitochondrial directed ratiometric fluorescent probe for quantitive detection of sulfur dioxide derivatives
Authors: Gao Congcong , Tian Yong , Zhang Rubo , Jing Jing , Zhang Xiaoling
Published: January 2019

A good biocompatibility fluorescence probe for imaging of sulfur dioxide derivatives in cancer cells.
Selectivity, ligand deconstruction, and cellular activity analysis of a BPTF bromodomain inhibitor
Authors: Kirberger Steven E. , Ycas Peter D. , Johnson Jorden A. , Chen Chen , Ciccone Michael F. , Woo Rinette W. L. , Urick Andrew K. , Zahid Huda , Shi Ke , Aihara Hideki , McAllister Sean D. , Kashani-Sabet Mohammed , Shi Junwei , Dickson Alex , dos Santos Camila O. , Pomerantz William C. K.
Published: January 2019

19F NMR-guided development of a BPTF chemical probe through SAR and ligand deconstruction.
Directed tubule growth from giant unilamellar vesicles in a thermal gradient
Authors: Talbot Emma L. , Kotar Jurij , Di Michele Lorenzo , Cicuta Pietro
Published: January 2019

We demonstrate experimental control over tubule growth in giant unilamellar vesicles with liquid–liquid phase coexistence, using a thermal gradient to redistribute lipid phase domains on the membrane.
Tuning of thermoresponsive pNIPAAm hydrogels for the topical retention of controlled release ocular therapeutics
Authors: Bellotti Elena , Fedorchak Morgan V. , Velankar Sachin , Little Steven R.
Published: January 2019

Reduction of the LCST of a pNIPAAm-based thermoresponsive hydrogel through modification of PEG content and molecular weight.
Peptide-biofunctionalization of biomaterials for osteochondral tissue regeneration in early stage osteoarthritis: challenges and opportunities
Authors: Bicho D. , Ajami S. , Liu C. , Reis R. L. , Oliveira J. M.
Published: January 2019

Osteoarthritis is a degenerative joint disease characterized by the progressive deterioration of articular cartilage, synovial inflammation and changes in periarticular and subchondral bone, being a leading cause of disability.
Correction: Ionic-liquid supported rapid synthesis of an N-glycan core pentasaccharide on a 10 g scale
Authors: Li Wei , Gao Yu , Li Qing , Li Zhong-Jun
Published: January 2019

Correction for ‘Ionic-liquid supported rapid synthesis of an N-glycan core pentasaccharide on a 10 g scale’ by Wei Li et al., Org. Biomol. Chem., 2018, 16, 4720–4727.
Characterization of recombinant fructose-1,6-bisphosphatase gene mutations: evidence of inhibition/activation of FBPase protein by gene mutation
Authors: Topaz Gemma , Epiter-Smith Victor , Robalo Cristina , Emad Megan , Ford Vanessa , Daley Jadine , Byron Jennifer , Stieglitz Kimberly A.
Published: January 2019

Specific residues of the highly regulated fructose-1,6-bisphosphatase (FBPase) enzyme serve as important contributors to the catalytic activity of the enzyme. Previous clinical studies exploring the genetic basis of hypoglycemia revealed two significant mutations in the coding region of the FBPase gene in patients with hypoglycemia, linking the AMP-binding site to the active site of the enzyme. In the present study, a full kinetic analysis of similar mutants was performed. Kinetic results of mutants Y164A and M177A revealed an approximate two to three-fold decrease in inhibitory constants (Ki’s) for natural inhibitors AMP and fructose-2,6-bisphosphate (F2,6-BP) compared with the Wild-type enzyme (WT). A separate mutation (M248D) was performed in the active site of the enzyme to investigate whether the enzyme could be activated. This mutant displayed an approximate seven-fold increase in Ki for F2,6-BP. Interfacial mutants L56A and L73A exhibited an increase in Ki for F2,6-BP by approximately five-fold. Mutations in the AMP-binding site (K112A and Y113A) demonstrated an eight to nine-fold decrease in AMP inhibition. Additionally, mutant M248D displayed a four-fold decrease in its apparent Michelis constant (Km), and a six-fold increase in catalytic efficiency (CE). The importance—and medical relevance—of specific residues for FBPase structural/functional relationships in both the catalytic site and AMP-binding site is discussed.
Supervised control strategy in trajectory tracking for a wheeled mobile robot
Authors: Gheisarnejad Meysam , Khooban Mohammad‐Hassan
Published: January 2019

In this study, a single input interval type‐2 fuzzy logic (SI‐IT2‐FLC) supervised adaptive neural‐fuzzy interface system (ANFIS) controller is proposed for the velocity tracking task of a two‐wheeled mobile robot (WMR). The suggested technique can handle the inherent nonlinearities, uncertainties and external disturbances in the system model by a new supervised controller. The robot control design is accomplished by two separate phases including kinematic controller, which is characterized using the kinematic model of the robot, and dynamic controller, which is designed using the physical features of the robot dynamics. In particular, an SI‐IT2‐fuzzy PD (SI‐IT2‐FPD) controller is initially applied for the trajectory tracking problem in the two‐WMR. In this way, the impact of the footprint of uncertainty (FOU) on control surface (CS) generation is studied, i.e. several CSs were generated by changing a single coefficient which shapes the FOU. Then, a new SI‐IT2‐FPD supervised ANFIS controller is developed for the concerned robot system. To enhance the efficiency of the suggested controller, the baseline PD gains of the SI‐IT2‐FPD are adjusted in a heuristic manner. Finally, a prototype of the concerned robot is implemented to investigate the feasibility and applicability of the proposed framework in a real‐time platform.
Embedded dual switched‐capacitor based continuous input current switched‐inverter for renewable energy application
Authors: Ahmad Anish , Singh Rajeev Kumar
Published: January 2019

This study presents a high voltage gain embedded dual switched‐capacitor‐based continuous input current impedance source inverter for renewable energy applications. Renewable energy resources have low‐output voltage generation capability, and the converter needs to operate on the extreme duty cycle for high voltage requirements. To achieve high voltage gain, a conventional impedance source inverter needs to operate on a high duty cycle, which leads to the reduction in modulation index. Operating at a reduced value of modulation index leads to poor inversion operation with poor output power quality. In order to take care of this issue, an embedded dual switched‐capacitor‐based inverter is presented for high voltage gain in low shoot‐through duty cycle. The proposed inverter is suitable for DC–AC power conversions such as solar photovoltaic where a low‐input voltage is available, and it needs to be converted into high DC–AC output voltages. Anatomisation of operating principle, steady‐state analysis, passive design criteria, and comparison are discussed. The proposed inverter also has less capacitor voltage stress, less diode current stress, and higher efficiency than other impedance‐source inverters. The operation of the proposed inverter is verified through simulations and experimental results with a 600 W prototype.
Continuous provision of synthetic inertia with wind turbines: implications for the wind turbine and for the grid
Authors: Gloe Arne , Jauch Clemens , Craciun Bogdan , Winkelmann Jörg
Published: January 2019

In future power systems with little system inertia, grid operators will require the provision of synthetic inertia (SI) from renewable energy sources. Unlike today, grid operators may require continuous provision of SI. This can lead to an unwanted disconnection of wind turbine generators (WTGs) from the grid, and has the potential to cause a significant decrease of the energy yield and financial losses for the turbine operator. In order to avoid such situations a controller is proposed, which interprets the grid codes to the benefit of all parties involved. This can be achieved by a variable inertia constant, which changes with the operating point of the WTG. In this study, the behaviour of the variable inertia constant controller is described, assessed and verified with time domain simulations.
Integrated battery model in cost‐effective operation and load management of grid‐connected smart nano‐grid
Authors: Heidari Mehran , Niknam Taher , Zare Mohsen , Niknam Solmaz
Published: January 2019

This paper presents a comprehensive model of dynamic optimal operation management of the smart nano‐grids (NGs) including the micro wind turbines (WTs) and micro photovoltaics (PVs) as renewable energy sources (RESs) while micro turbines (MTs) and fuel cell (FC) are considered as non‐RESs. Furthermore, two types of lead‐acid and lithium‐ion batteries are considered besides the three types of controllable, curtailment‐able and must run loads to increase the flexibility of the proposed formulation. The different objective functions of NG operation problem to be minimised include operating cost, environmental damage cost of pollution gases and exchanged power cost with the main grid. Also the power losses of batteries are modelled using the quadratic functions based on types and output powers of considered batteries, while these losses impose additional cost to operation cost functions of batteries. A modified teaching‐learning‐based optimisation (MTLBO) algorithm is used to cope with the multiobjective problem considering the constraints.
Image edge detection method based on anisotropic diffusion and total variation models
Authors: Abdullah Yahya Ali , Tan Jieqing , Su Benyu , Liu Kui , Hadi Ali Naser
Published: January 2019

In this study, a novel image edge detection technique based on the combination of total variation (TV) and anisotropic diffusion (PM) models is presented. In the proposed technique, the authors first use the gradient magnitude to eliminate the noise, then utilise the adaptive weight function to detect the edges of the image. The adaptive weight function has a high ability to adapt and change according to the areas information (edges or flats areas). More specifically, TV filter is applied on the areas which suffer from double and false edges, whereas, anisotropic diffusion filter is applied on the areas which suffer from weak and discontinuous edges. Applying TV filter on the double edges areas will allow one to remove most of the false edges, and thus to obtain much sharper edges. While, applying anisotropic diffusion filter on the discontinuous edges areas will lead to obtaining robust and continuous edges. Consequently, less false edges besides high localisation accuracy were obtained. Experimental results demonstrate the superiority of the new approach in terms of removing the false edges and improving the localisation accuracy of the edges. As objective quantitative performance measures, the peak signal‐to‐noise ratio (PSNR) and Pratt's figure of merit (FOM) were used.
Energy supply in the Khabarovsk territory: intra-regional differentiation and problems of budgetary support
Authors: Dyomina Olga , Naiden Svetlana
Published: January 2019

The article is devoted to measuring solvable demand of population for energy supply services and the level of budgetary guardianship in Khabarovsk Krai. The authors show the differentiation in availability of energy supply services for consumers, explained by the geographical contrasts and existing system of settlement. There are two sources of energy supply in Krai: “Far Eastern Generating Company” (AO “DGK”) and objects of public energetics. The population pays for only a part of actual producers’ costs for energy supply services; the remaining part is compensated by the state through budgetary means. There are two ways to compensate high tariffs on energy supply for population: subsidies and privileges for consumers and subsidies for producers. The population that gets its energy from AO “DGK” pays for energy supply services almost entirely, while population that uses the services of public energetics pays only partially, with the state taking the burden upon itself to compensate the producers’ costs. In case of transitioning to full compensation, the scale of social budgetary support will increase significantly, which contradicts the logic of institutional transformation, aimed at lowering the financial burden of the state.
Role of Russia’s Asian regions in the energy sector of the country: priorities and prospects for development in the first half of the 21st century
Authors: Lagerev Anatoly , Khanaeva Valentina
Published: January 2019

This paper shows the role of Russia’s Asian regions in the production and consumption of energy resources for two scenarios (conservative and target) of the economy development in the country until 2035 and for the 2050 perspective. The dynamics and structure for the energy resources supply from the Asian regions to the European part of Russia and for export to the European and Asian countries is presented. The Asian regions are shown to still remain the main suppliers of energy resources in the country. By 2050, about 80% of the energy resources produced in the Asian regions will be resupplied outside their borders, 5657% of them for export.
Coal industry of the Republic of Sakha (Yakutia): tools and forecast
Authors: Pavlov Nikita , Petrov Nikolai
Published: January 2019

An approach to the development of tools for the formation of promising indicators characterizing the development of the coal industry of the Sakha Republic (Yakutia) is considered. Briefly, a possible version of the development of coal mining and coal consumption in the energy sector of the republic is presented.
Energy industry of the Republic of Buryatia: current state and prerequisites for further development
Authors: Borisov Gennadiy , Dondokov Zorikto
Published: January 2019

The article contains the results of a study of the state of the fuel and energy complex (FEC) of the Republic of Buryatia. The role of fuel and energy complex in the economy of the republic is analyzed in the article. The main problems, the solution of which is necessary for further development of the industry, including energy security and low efficiency of heat and power production in the power system, are identified by the author. The tasks of development of transboundary interaction with the energy system of Mongolia are defined. Possible options for gasification of Buryatia were studied. To ensure increased energy security of the Republic of Buryatia and the efficiency of the Buryat energy system, the main activity is the continuation of the construction of Ulan-Ude Thermal Power Station-2. The necessity of actualization of the development strategy of the fuel and energy complex of the Baikal region based on the diversification of the fuel and energy balance due to gasification, the development of gas processing and gas chemistry, the use of non-traditional and renewable types of energy is substantiated.
Features of the transport system of the Republic of Sakha (Yakutia) and the substantiation of the need for searching of ways to increase the reliability of coal supply
Authors: Zakharov Vasiliy
Published: January 2019

The article describes the transport corridors of coal delivery to remote hard-to-reach consumers of the Republic of Sakha (Yakutia). A brief description of the waterways and the timing of their operation are given. The conditions of functioning of winter roads are reflected. The main risks of coal delivery are described. The article describes the whole cycle of finding coal in the open air from the moment of production to the final consumption in boiler houses. The results of experimental analysis and modeling of oxidation state during delivery are presented. The economic inexpediency of forming long-term coal reserves is explained, while maintaining the traditional technology of transportation and storage. The economic difficulties of the organization of coal supply have been singled out. As a result of the analysis of the current state of coal supply, key points of improving the coal supply system of the Republic of Sakha (Yakutia) are highlighted.
Prerequisites for using solar potential to supply power to consumers in the central ecological area of the Baikal natural territory
Authors: Khalgaeva Nadezhda , Tuguzova Tatyana
Published: January 2019

We address the possibility for using solar potential to supply power to consumers in the central ecological zone of the Baikal natural territory, given its special conservation status. Based on an analysis of observations made during expeditions, we revealed the specific features of the location of the settlements and the sites where solar equipment is installed. The considered territory was zoned based on an analysis of the solar potential parameters. The paper presents the priority areas for the solar potential implementation for energy purposes, with a focus on the potential sites for installation of photovoltaic power plants and solar heating systems. Key words: total solar radiation, sunshine duration, annual distribution of direct and diffuse radiation, priority areas of solar potential implementation, effects of solar plants
Workability and Strength Properties of Class C Fly Ash-Based Geopolymer Mortar
Authors: Cornelis Remigildus , Priyosulistyo Henricus , Satyarno Iman , Rochmadi
Published: January 2019

Fly ash-based geopolymer mortar normally achieves expected properties by heat curing. This becomes one of the obstacles for in-situ applications. The development of high calcium fly ash-based geopolymer mortar, suitable for ambient curing, will gain the applicability of such a material in civil structures. This article reports the results of an experimental study on mortar workability and the increasing of compressive strength of class C fly ash-based geopolymer mortar created in ambient curing condition. The main synthesis parameters such as alkali to the cementitious mass ratio varied from 30% to 40% by an increment of 5% and absolute volume of paste to absolute volume of voids of the aggregate ratio varied from 1 to 2 by an increment of 0.25. These parameters were designed to figure out their individual effects on mortar workability and the mechanical properties for the production of geopolymer mortar. The results suggested that the workability of mortar generally increased by using alkali to the cementitious mass ratio. The compressive strength of 60 MPa and the direct tensile strength of 2.8 MPa, the ratio of alkali to the cementitious mass of 0.35 and absolute volume of paste to absolute volume of voids of the aggregate ratio was 1.5; it was obtained at ambient temperature after 28 days of age. The results will be useful for developing the knowledge for the use of class C fly ash in producing geopolymer concrete, which is currently in progress. Hopefully, this contribution of research will improve the applications of such new binding material in the future.
A study into flexural, compressive and tensile strength of coir-concrete as sustainable building material
Authors: Rumbayan Rilya , Sudarno  , Ticoalu Adriana
Published: January 2019

Coir has been known as a potential natural fiber for many sustainable construction material developments due to its wide availability and sustainable resource of coconut tree. This research study aims to investigate the flexural, compressive and tensile properties of concrete incorporating coir fiber and to find the fiber content which gives optimum results. In this study, coir concrete specimens were cast and tested with variations of fiber content of 0%, 0.25%, 0.5%, 0.75%, and 1% by weight of aggregates. Flexural test was conducted based on SNI 4431:2011, compressive test was conducted based on SNI 1974:2011 and tensile test was conducted based on SNI 2491:2014. Slump tests and unit weight showed reduced values when fiber content was increased. Flexural, compressive and tensile strengths of coir-concrete at a 28-day curing were optimum for the variation with 0.25% fiber content. Compressive strength of control concrete at 28 days was approximately 23 MPa while BS-0.25 was 27.5 MPa. Flexural strength of control concrete was 5 MPa while BS-0.25 was 6 MPa. Tensile strength of control concrete was 3 MPa while BS-0.25 was 2.5 MPa. Results from the study showed that the presence of 0.25% fiber (by total weight of aggregate) in the concrete gives approximately 19% improvement in 28 days compressive strength and flexural strength.
Mechanical properties of sulphate reduction bacteria on the durability of concrete in chloride condition
Authors: Tambunan Teddy , Juki Mohd. Irwan , Othman Norzila
Published: January 2019

In construction, concrete durability is an important material globally used in engineering, material of which can be applied in the fields of specialized marine construction. The ingress of chloride into concrete causes deterioration in the concrete due to the reinforcement corrosion. Adding bacteria into concrete can improve material properties and increase durability with mechanism resist chloride ingressed in the concrete . Ingress of Chloride into the concrete of bacteria is particularly suited for applications of chloride ion penetration in concrete. The objective of the research is to determine the effect of adding bacteria into the concrete properties. The bacteria used in this research is locally isolated and enriched to the suite with the concrete environment. The type of the bacteria used is identified as Sulphate Reduction Bacteria (SRB). The SRB added into the concrete mix with concentrations of 3%, 5% and 7%. Whereas, concentration of bacteria water of cement is 0.5. The mechanical properties test conducted with 28th, 56th, 90th, 180th and 360th day of curing period. The test was using cyclic wetting and drying to study the exposure to chloride condition, such as compressive strength, tensile strength and flexural test. Cubes in the size of 150 mm × 150 mm × 150 mm were prepared for compressive strength test and cylinder 150 mm × 300 mm were prepared for the tensile strength test. The flexural strength test was on the prism in the size of 100 mm × 100 mm × 500 mm. The result of compressive strength test shows, that gave significant strength of 66.3 MPa on the 360th day. The tensile strength and flexural strength have a similar trend as compressive strength results, where both results were optimum . The tensile strength test shows that 4.52 MPa tends to control 3.96 MPa. The result of flexural strength test was 8.23 MPa for compared to control of 5.99 MPa. The overall results of the bacteria indicate promising outcome and further study on chloride condition capability is encouraging.
Optimization of Reinforced Concrete Column Using Android- based Mobile Application
Authors: Lautan Wijaya Nusantara Johan , Aminullah Akhmad , Triwiyono Andreas
Published: January 2019

Reinforced concrete column has complicated calculations. Designer usually acts trial and error to get the optimum dimension and reinforcement according to the occurred loads. It takes long process and the result is not always be the most economical section. Nowadays smartphone with its various applications is very popular among societies. Besides being more flexible in place and time, smartphone has ease in operation and is commonly used by people. Hence, those advantages can be used to optimize reinforced concrete column quickly and accurately. The application named “C2 App” (Concrete Column Application) had been created by accommodate regulation in Indonesia (SNI 2847:2013). Biaxial calculation used Bresler’s approach, while calculation of slender column applied Moment Magnification Method. The application is able to show interaction diagram, section drawing, and result tables. Moreover, the application was equipped with local database, and detailed calculations in pdf format to support the real project. Validation was done with computer-based software named CSiCol and ASDIP Concrete, whereas the optimization result was compared with other designs which used ACI Diagrams and Particle Swarm Optimization method. The application was pretty accurate and could provide a more economical section.
Analysis of accident in Indonesian construction projects
Authors: Ghuzdewan Toriq , Damanik Petrus
Published: January 2019

The numbers of accidents in construction projects in Indonesia is the highest in the industries as mentioned by the Ministry of Manpower and Transmigration’s publication. Construction accidents are often reported in the media such as televisions, newspapers, magazines, and the internet. This study employs construction accident data from the internet, from the year 2012 to 2014 using search engines with keywords such as construction work accident, falling from height, an accident from falling objects, electrical shock, etc. The data are then analyzed to understand the types, causes and impacts of accidents and suggestion for future improvement. The results showed that of the 332 data obtained, accidents in building projects are the highest (47%), followed by that in housings (42%) and others (11%). According to the types of accidents, electrical shock is the highest (115 cases), followed by falling from height (91 cases) and stricken by objects (83 cases). The causes of accident due to unsafe acts was 61% and unsafe condition was 39%. Most of the accidents can be categorized as fatal (68%), serious (16%) and catastrophic (14%). It is recommended that administrative action and Personal Protective Equipment (PPE) should be applied to reduce the risk of accident.
Apartment project risk assessment under market uncertainty; a case study in Wonokromo, Surabaya
Authors: Sutantio Aditya , Wiguna I Putu Artama , Tri Joko Wahyu Adi
Published: January 2019

Apartment projects are developed based on a set of assumptions; therefore they have to face risks and uncertainties. One of the most important risks is the uncertainty of the market. The economic condition that causes market slow-down in Indonesia recently has led to some certain of stagnation of apartment development, of which impacts remain for years. In such condition, it is necessary to understand how to measure risks before making a decision. The objective of this paper is to assess risk in apartment project under market uncertainty, using quantitative tools selected from the theory associated with the investment decision. The parameters are market risks and operating risks. Market risk is subdivided into capital market risk(CMr), valuation risk (Vr) and market growth rate risk (MGRr), while real estate operating risk is subdivided into operating risk (Or), development risk (Dr), leasing risk (Lr), leasehold risk (LHr) and leverage risk (LVr). The riskiness values are categorized into three classes: conservative, moderate and aggressive. A leased apartment development project in Wonokromo, Surabaya was selected as a case study. The project covered 8,773 square meters of land and consisted of one tower with total 31,829 square meters gross floor area, equipped with parking lots and amenities. The study found out that The CMr was 36%, Vr was 13 %, MGRr was 50%, Or was 112%, Dr was 47%, Lr was 215%, LHr was 61% and LVr was 156%. Although the overall project risk values lie in conservative category, since the level of leasing risk is in aggresive range, more comprehensive investigation should be carried out during a decision-making to reduce the negative impact of risks.
Seismic Performance Evaluation of a Multistory RC Building in Padang City
Authors: Tanjung Jafril , Maidiawati  , Nugroho Fajar
Published: January 2019

Since a long time ago, Padang City has been recognized as one in most-earthquake and tsunami prone city in the world. The successive significant earthquakes that have struck western coast of Sumatra Island from 2004 to 2010 seems to warn the city about its prone condition. The last major Padang-Pariaman earthquake on September 30, 2009, for instance, has caused hundreds of death and lousy damage to thousands of houses and buildings in city. Recently, several new multistory reinforced concrete (RC) buildings have been established in this area. Its include such buildings as government office, mosques, hotels, school and university. The city government plans to use these buildings as vertical evacuation facilities if an earthquake followed by a tsunami hit the city in the near-future. As a consequence, of course, these infrastructures should be well designed and constructed to resist the future earthquakes motion. This paper discusses an evaluation of the seismic performance of an existing multistory RC building in Padang city. The building was a ten-story of hotel RC building located near the coastline of Padang city. A series Pushover and Time History Analyses were conducted to examine the seismic performance of the target R/C building. It uses STructural Earthquake Response Analysis (STERA-3D), a computer software based on the nonlinear finite element method. The Pushover analysis was conducted for maximum drift ratio 1/200 in X and Y directions, respectively. The input ground motion in a maximum acceleration of about 400 gals and 600 gals for 60 seconds’ excitation were used for the Time History Analysis. These input ground motions were generated from the recorded ground motion of 2009 Padang-Pariaman earthquake. The result of the analyses suggest that the current target multistory RC building has outstanding seismic performance. The result is based on the level of damage of the structural components, base shear, inter-story drift, lateral displacement, dynamic responses and the seismic capacity spectrum of the analytical model.
The effect of tsunami loads on Pasar Raya Inpres Block III building in Padang City based on FEMA P-646
Authors: Fauzan  , Anas Ismail Febrin , Siregar Nurpadila , Al Jauhari Zev
Published: January 2019

Pasar Raya Inpres Block III building in Padang City is a traditional market building that located in the high seismic zone and prone to tsunami. The building consists of five floors that planned to be used as a vertical evacuation for the surrounding community. However, in designing the building structure, it is only planned to strongly against the earthquake load and it does not take into account the tsunami load. In this study, the effect of tsunami load on the building was investigated. This building will be analyzed and modeled by using ETABS v.9.7.1 software. The applied earthquake load in the building refers to SNI 1726:2012, while the tsunami loads refer to FEMA P-646/2012. From the analysis results, it was found that the columns of the building are capable of restrained the tsunami loads, but the beams were not strong enough to withstand the tsunami loads. The beam failure occurred due to the small load-bearing capacity of the beams against the tsunami loads includes buoyant force, additional gravity load, and uplift hydrodynamic force. Furthermore, the retrofitting of the building should be carried out, especially on the beams of the building before being used as a tsunami vertical evacuation building.
Effects of horizontal web reinforcement on cyclic behavior of RC squat walls
Authors: Wibowo Leonardus S.B. , Cheng Min-Yuan
Published: January 2019

This paper evaluates the effects of horizontal web reinforcement on cyclic behaviour of RC squat wall using test results of three pairs of specimens. One specimen was tested by the authors while the other five were adopted from the existing researches. Each specimen pair was designed with approximately the same design parameters, except that uniformly distributed horizontal web reinforcement was provided in one specimen only. Shear stress demand, evaluated based on the shear associated with the development of flexural strength at the base, was approximately $3.5\sqrt {{{f'}_c}} (psi)$, $6.0\sqrt {{{f'}_c}} (psi)$, and $8.0\sqrt {{{f'}_c}} (psi)$, respectively, for each specimen pair. Test results show that specimen with uniformly distributed horizontal web reinforcement exhibited larger deformation capacity compared to specimens without it. Specimen peak strengths, on the other hand, appear to be similar with and without uniformly distributed horizontal reinforcement and can be satisfactorily predicted by nominal flexural strength.
Investigation of brick masonry with using of bad quality of bricks and reinforced concrete frame
Authors: Triwiyono Andreas , Eratodi I Gusti Lanang Bagus
Published: January 2019

In some region typical resident houses are made of brick masonry. Ministry of Public Work Indonesia and JICA [2] have published a guideline as key requirements for safer houses. A study was carried out to obtain the effect of disparities material quality on the performance of the brick masonry. Six wall specimens were experimentally tested in-plane direction until failure by observing deformation, cracks, and uprooting of the wall. Study based on the finite element was also used by implementing the three-dimensional stress state of concrete and masonry and elastic-plastic for reinforcement. From the study it can be concluded that: the wall following guideline has enough strength but could not reach the load capacity because the wall was uprooted. Bad quality of concrete did not affect the stiffness and strength of the walls. The strength of the walls with a poor quality of mortar and poor quality of bricks comparison to the wall with standard quality of bricks had the strength of about 78%. Wall without plastering with a poor quality of the bricks, mortar, and concrete reduced the strength and stiffness to about 41% compared to the wall with standard quality. The proposed FE model can predict the strength of the wall well but not for its stiffness. The model especially the masonry material model still needs to be developed in order to obtain the close result with the laboratory test.
The experiment of four-point bending behaviours of helicoidally laminated CFRPs
Authors: Ishizawa Ikuma , Matsumoto Takashi , Kondo Kenta
Published: January 2019

The purpose of this study is to mitigate the brittle behaviour of CFRP. CFRP is a composite material of carbon fibre and a thermosetting resin. As a feature, it has a low density than metallic materials such as steel and aluminium, and it is excellent in specific strength, specific stiffness, and is corrosion resistant. In the civil engineering field, CFRP is expected to be utilized for durability improvement and long life achievement. However, it is necessary to be careful when using it as a primary member, because the behaviour at the time of fracture is very brittle, thereby it is necessary to set a large safety factor at the time of design. One way to achieve the purpose of the current study is to follow a biological structure, so-called biomimetics. In this study, mantis shrimp is selected. The characteristic structure of its forefoot is that chitin fibres are stacked while changing helicoidally their angles. It is said that the forefoot can withstand a thousand times the force of its own weight because of its structure. Helicoidally laminated CFRP is fabricated by processing prepreg sheets of unidirectional carbon fibres. Four laminated structures were examined in which four-point bending experiments were carried out under displacement control of 2 mm/min, and load and displacement were recorded. During the experiments, the specimens were observed until fracture with a video camera. As a result, the brittle behaviour was improved significantly as the orientation angle difference of the fibre sheets decreased.
An Analysis of elastic and inelastic lateral torsional buckling of web-tapered I beams using the finite element method
Authors: Karta Wijaya Paulus , Lauw Giok Swan Cecilia , Sadrina Noor Ghassani
Published: January 2019

Elastic and inelastic lateral torsional buckling of simply web tapered I beam is studied using the finite element method. The length of the beams is 8000 mm for elastic lateral torsional buckling and 4000 mm for inelastic lateral torsional buckling. The depth of cross section at one end is 500 mm and at the other end it is varied. The thickness of the flange is 16 mm and the thickness of the web is 10 mm. The section of the beams is compact. The beams are loaded by end moments. The ratio of end moments at one end and the moments at the other end are varied. The beams are assumed to have geometric imperfection and the distribution of imperfection follows the shape of the first buckling mode of elastic lateral torsional buckling of the beam. The amplitude of the imperfection is taken one milimeter at the top flange in lateral direction. The load is increased until the beams collapse. The ultimate load is considered as the critical moments of the beams. The results of the analysis are compared to nominal lateral torsional buckling moments using the method presented in the AISC Design Guide 25 (Design Guide for web tapered members). It can be concluded that usually the critical moments of the collapse analysis are close to the critical moments of the design guide. But sometimes it is less than the design guide and it means design guide is sometimes is not on the safe side.