bluuebunny/crossref_metadata_2025 huggingface dataset:
Experimental study on ultra-low raw emissions in diesel/methanol dual fuel engine based on dual-loop EGR
Authors: Wu Taoyang , Yao Anren , Qu Guofan , Ai Youkai , Wang Wenchao , Ma Baodong , Yao Chunde
Published: November 2022

In this paper, an experimental investigation on achieving ultra-low raw emissions in a diesel/methanol dual fuel engine based on dual-loop EGR was carried out. The effect of dual-loop EGR (High pressure EGR and low pressure EGR) on the combustion, performance and emissions of methanol engine has been studied comprehensively. The results show that ultra-low NOx (<0.4g/kWh) and PM (<10 mg/kWh) emissions can be achieved simultaneously in diesel methanol dual fuel engine with the help of EGR. The combustion phase is delayed with the increase of EGR rate in both EGR modes. However, the methanol equivalence ratio and in cylinder combustion temperature in high pressure EGR mode are significantly higher than those in low pressure EGR mode. Therefore, the CO and THC emissions are obviously lower in high pressure EGR mode than that in low pressure EGR mode. The combustion efficiency and brake thermal efficiency of the engine are 1.9% and 9.6% higher in high pressure EGR mode than those in low pressure EGR mode, respectively.
Characterization of roadside air pollutants: An artery road of Lanzhou city in northwest China
Authors: Zhang Yonglin , Yang Daoyuan , Wu Rui , Li Yue , Yang Xiaowen , Wang Renjie , Xu Honglei
Published: November 2022

Due to the lack of air and traffic monitoring data in China, this study employed a remote sensing (RS) system and air quality monitoring sensors to investigate the air pollutant concentrations, traffic profiles and meteorological data in order to characterize roadside pollutant concentrations and identify their influence factors for a major road in Lanzhou. The results suggested that the temporal variations of concentrations of SO2, NO2, PM2.5, PM10 and CO peaked at 5:00-7:00 while O3 peaked at 17:00. The concentrations of roadside air pollutants were lower on weekdays than weekends except O3. The concentrations of PM2.5 and PM10 declined with the height of the monitoring sites increased, peaking at 2-meter height whereas SO2, NO2, CO, and O3 reached their highest concentrations at 4-meter height. The concentrations of roadside NO2 and CO show positive correlations with the volume of heavy-duty trucks (HDTs) and light-duty passenger vehicles (LDPVs), respectively. This study provided scientific support to the establishment of roadside air quality monitoring systems and the assessment of the environmental and health impact from vehicle emissions.
Distance classifier ensemble based on intra-class and inter-class scatter
Authors: Guo Yaqin
Published: November 2022

Distance classifier ensemble method based on Intra-class and Inter-class Scatter is proposed in this paper. By Bootstrap technology, the training samples are sampled repeatedly to generate several subsample set, define Intra-class and Inter-class Scatter matrix with subsample set, train subsample set with scatter matrix, generate individual classifier. In the classifier ensemble, the results are integrated with the relative majority voting method. Experiment is tested on UCI standard database, the experimental results show that the proposed ensemble method based on Intra-class and Inter-class Scatter for distance classifier is effective, and it is superior to other methods in classification performance.
Deformation prediction programming based on MATLAB and BP neural network
Authors: Zheng Haoxin , Chang Zhanqiang , Liu Jiaxi
Published: November 2022

In order to solve land tension problems, high-rise buildings become more and more common in the modern big cities. Meanwhile, it is necessary to monitor the deformation of the high-rise buildings for their safety. Based on the deformation monitoring data, we can predict subsequent data, and then analyze the security situation of buildings. In this paper, we will introduce a prediction method, in which BP neural network and MATLAB program are applied. BP neural network is an algorithm that simulates biological neurons to train network learning. The principle of artificial neural network is to build a mathematical model of brain neural activity by imitating the neural activity of human brain. BP neural network has strong learning ability, generalization ability, nonlinear mapping ability and fault tolerance ability.
Review on the kerogen deformation mechanism
Authors: Zheng Huimin , Zhang Haozheng , Tang Zheyuan
Published: November 2022

Shale gas is unconventional natural gas energy stored in shale, and is one of the important substitutes for conventional oil and gas resources. Since amorphous kerogen is the main component of shale organic matter and has a high degree of deformation ability, it is a key factor to improve shale gas recovery. As an emerging mining technology CS-EGR, the CO2 injection method replaces the hydraulic pressure method, thereby alleviating the greenhouse effect and energy crisis. The basic understanding of the microscopic mechanism of the multicomponent competitive adsorption and diffusion of the adsorbate in kerogen will provide a theoretical basis and guidance for further understanding of kerogen deformation and further CS-EGR. Starting from the summary of experimental research, this paper systematically summarizes the kerogen model used for kerogen deformation research and discusses the effects of adsorbate, load, moisture, temperature, pressure, and geological depth on different kerogen structures of different maturity. The effect of kerogen deformation.
Evaluation and analysis of the sustainable development ability of enterprise supplementary medical insurance fund based on PSR Model -- a case study of a large state-owned enterprise in Anhui Province
Authors: An Siqing , Wu Xiaoyong , Zhou Tian , Huang Jin , Tang Qinqin , Zhang Ning
Published: November 2022

Objective: In order to evaluate the sustainable development ability of the supplementary medical insurance fund of a large state-owned enterprise in Anhui Province, this paper puts forward the countermeasures to promote the sustainable development of the supplementary medical insurance fund of enterprises. Methods: By constructing PSR evaluation model and using entropy method to determine the index weight, the comprehensive evaluation value of sustainable development ability of supplementary medical insurance fund of a large state-owned enterprise in Anhui was calculated. Results: Horizontally, the highest comprehensive ability is the headquarters of the large state-owned enterprise, which is 0.430, and the lowest is Qingyang County, which is 0.147; Vertically, the comprehensive evaluation value of the sustainable development ability of enterprise supplementary medical insurance increased from 0.200 in 2016 to 0.239 in 2020, with an average annual increase of 4.55%. Conclusion: The influence of pressure factors on fund operation in different regions is quite different, and the development among regions is unbalanced. It is necessary to improve the management level of enterprise, enhance the fund raising ability, pay attention to overall planning and top-level design, promote regional coordinated development as a whole, continuously improve the fund investment management ability, and actively broaden the fund investment channels.
STF-based diagnosis of AUV thruster faults
Authors: Jiang Chunmeng , Lv Jinhua , Liu Yanli , Wang Gaoyang , Xu Xin , Deng Ying
Published: November 2022

The diagnosis of thruster faults of autonomous underwater vehicles is studied in this paper. Based on the theory of strong tracking filter (STF), the AUV motion model and the thruster fault model are established. The STFs are designed for each thruster for the purpose of fault diagnosis. The AUV state and the fault deviation of the thruster are estimated online before the thruster faults are diagnosed based on residual analysis. The simulation experiments were conducted to verify the feasibility and effectiveness of the STF-based diagnosis of AUV thruster faults.
The influence of environmental regulation on green total factor productivity——based on the Yangtze River panel data empirical research
Authors: Lyu Hongfen , Qiu Ting
Published: November 2022

At present, the environmental problem is increasingly serious, how to achieve the sustainable development has become very important recently. This paper used the data of 106 prefecture-level cities of the Yangtze River Economic Belt to study the effect of environmental regulation on green total factor productivity. The results show that environmental regulation can significantly improve the GTFP. There is significant heterogeneity. Also found that the level of economic development has a threshold effect.
Characterization of porous media by nuclear magnetic resonance beyond fast diffusion limit with numerical simulation
Authors: Zhang Yan , Zhou Yu
Published: November 2022

Nuclear magnetic resonance logging is an important formation detection technique in the petroleum industry, which is always used to detect formation pore structure and fluid identification. However, conventional nuclear magnetic resonance characterization methods assume that the formation pore medium are in fast diffusion regime. In complex formations, non-fast diffusion regimes (intermediate diffusion and slow diffusion) are also present. In the previous paper [13], a new method for characterizing porous media with non-fast diffusion regime and uniform pore size distribution by T2-T2 pulse sequence is proposed. In this research, the T2-T2 signals of periodic stacked pore models beyond fast diffusion regime are numerically simulated by the random walk algorithm, and the pore size - surface relaxivity maps are respectively inverted, the relationship between pore structure and correlation maps are discussed. The results provide theoretical foundation for characterizing pore structure beyond fast diffusion limit.
Study on a method of prolonging the life of catalytic combustion sensor
Authors: Wang Bowen
Published: November 2022

The catalytic combustion combustible gas sensor is restricted by the principle, process, environment and other factors. When it is used in the actual working environment, the output value will drift and the measurement error will increase with the passage of time. The longer the service time is, the more serious the problem of sensitivity degradation will be, until it completely fails. In general, the effective service life of the sensor is only 1-2 years. Based on the conventional detection technology, this paper proposes the constant temperature bridge method based on the programmable constant current source. By reducing the use frequency of the catalytic sensitive element, it can avoid the problem that the sensitivity of the element drops too fast under frequent use, and can effectively extend the service life of the sensor to about one time.
Numerical studies of the interaction mechanism between the pilot flame and main flame
Authors: Zhang Lili , Cui Yongzhang , Yin Pengfei
Published: November 2022

The interaction mechanism between the rich premixed pilot flame and lean premixed main flame was investigate in this paper. A two-dimensional numerical model was adopted with detailed chemistry and species transport and with no artificial flame anchoring boundary conditions. The transport and reaction characteristics on the both sides of the main flame were analysed with the equivalence ratio via from 0.6 to 0.75. The results show that the radicals diffuse from the pilot flame to the reaction zone of the main flame, which contributing to the change of species concentration and chemical reaction rate. The pilot flame can the increase flame propagation speed, lowered the position of flame base and enhance the flame stability of the main flame.
Artificial intelligence of cultivating the communication ability of college students majoring in accounting in the context of the Internet
Authors: Zhang Xiaojiao , Zhang Liheng
Published: November 2022

With the impact of the development of artificial intelligence on the accounting industry, the society puts forward new requirements for the professional quality of accountants, especially the communication ability. This change leads to the communication ability of accounting students can not meet the changing needs of social development. In order to study this difference, this paper, in the form of Web information analysis and questionnaire survey, analyse the problems existing in the cultivation of communication ability of college students majoring in accounting in the era of artificial intelligence from three aspects - market demand, talent cultivation and cultivation subject, and puts forward some targeted suggestions on the curriculum and teaching content of colleges and universities according to the industry and market demand, so as to cultivate the students’ communication ability Cultivate modern accounting professionals to meet the needs of the market.
Artificial intelligence technology in battlefield situation awareness
Authors: He Ling , Hu Yahui , He Song , Luo Gang
Published: November 2022

In order to make further significant researches on battlefield situation awareness, the paper summarized the challenges in the field at first, which can be listed as the following: the massive and large data makes situation understanding difficult; the rapid change of data makes situation prediction difficult; the complex and heterogeneous data makes situation display difficult. Aiming at the above problems, the paper then discussed the application of artificial intelligence technology, such as knowledge graph, natural language processing and expert system. The appropriate applyment of relevant artificial intelligence technology will greatly improve the capability of battlefield situation awareness.
A method to estimate urban work zone intersection capacity under multiple influencing factors
Authors: Qie Entian , Li Ruoyang , Li Danna
Published: November 2022

Work zones generate significant congestion in urban centers, yet the influence of various capacity factors in urban arterials and intersections are poorly understood. This paper analyzes the influence of the following factors on urban arterial and intersection work zone capacity from 22 intersections: heavy vehicle flow, heavy vehicle percentage, work zone length, maximum speed limit, entrance lane width, left turn volumes, entrance and exit lane width reductions, and intersection length and width. An urban work zone was modeled using VISSIM simulation software, and regression models were developed based on the reduction coefficients with MATLAB software for fitting analysis. The results show that the proposed model estimated work zone capacity with high accuracy. Urban work zones were found to reduce capacity by 64% in the selected arterial and by 35% in the selected intersection, with corresponding increases in delay and queue length. The model also estimates the capacity improvement that can be expected given various mitigation factors. Transportation agencies may find work zone capacity estimates useful when planning construction in critical urban centers.
State identification of large diameter wet steam pipeline in nuclear power conventional island
Authors: Wu Qingqun , Fan Shaohua , Li Gaoqiao , Yang Zhiping , Wang Ningling
Published: November 2022

The safety of nuclear power plant is an inevitable condition for maintaining the long-term and stable development of nuclear power. Pipeline vibration is one of the common causes of power plant operation faults. Therefore, the state identification of pipeline vibration is very important. Taking a nuclear power heating pipeline as an example, the original vibration signal is decomposed and reconstructed by Wavelet Packet Transform, and the energy eigenvectors in X, Y and Z directions are established. In order to analyze the state of pipeline more accurately, two recognition algorithms of support vector machine (SVM) and SOM neural network are proposed. By comparing the classification effect and classification accuracy of the SVM before and after optimization, the optimized SVM and SOM neural network, it is concluded that the optimized SVM has better effect on pipeline state recognition, and the effectiveness of this method on pipeline state recognition is verified.
Numerical simulation of formation optimization for a fleet of unmanned surface vehicles based on a minimum energy consumption requirement
Authors: Dong Zhenpeng , Liang Xiao
Published: November 2022

This study proposes a hydrodynamic optimization strategy focusing on minimum energy consumption to construct the formation of a fleet of unmanned surface vehicles (USVs) by transforming the longitudinal offset and transverse separation. USVs were used instead of Autonomous Underwater Vehicles (AUVs) to fully consider the influence of a wave on energy-savings and to address undersize spacing and limited wake. The numerical model provided reasonably accurate results when compared against a series of experimental prototype results. The body force model was used to replicate the impact of the propeller, and an echelon formation was arranged considering the aft wedge wave pattern region induced by the Kelvin wave. The energy consumption equations of two-, three-, and four-hull formations were denoted by resistance components and used to determine the energy relationship between individuals and collectives. Additionally, an optimization platform was developed to integrate the application programs because the computation times were extensive for numerical simulations of spacing configurations transformation
Prediction and optimization of tourists’ spatial-temporal behavior during peak period in scenic spots: a simulation-based analysis
Authors: Chen Liqiong , Ge Peng , Liu Zhusheng
Published: November 2022

Tourists’ spatial-temporal behavior has complex and dynamic randomness, which affects the intelligent management of scenic spots. Understanding and mastering the spatial-temporal behavior of tourists within the peak period of scenic spots is one of the key means to improving the competitiveness of scenic spots and enhancing tourism satisfaction. This paper explores how to effectively optimize the tourists’ spatial-temporal behavior and improve the overall efficiency of scenic spots. Firstly, we built a simulation model and found the transfer change law between attractions through historical data. Then, we predicted the spatial-temporal distribution of the number of tourists to their subsequent attractions and selected the minimum load attraction as the next destination for tourists. Finally, the simulation experiment proves that the dynamic selection optimization based on individual tourist behavior can balance the scenic spot load and alleviate the congestion level.
Fault diagnosis of AUV based on sliding-mode observer
Authors: Jiang Chunmeng , Lv Jinhua , Wu Xiang , Chen Shuangquan , Zhang Hongrui
Published: November 2022

Designing of a sliding mode observer was finished based on the motion model of autonomous underwater vehicle (AUV). A Flutter decrease strategy for the sliding mode observer was discussed and the sliding mode observer was applied to the fault diagnosis of the AUV. Simulation experiment without faults was designed. Simulation experiment of sensor fault diagnosis and field trial of thruster fault diagnosis were undertaken. The validity and feasibility of this method were validated based on the analysis of the simulation and field trial results.
Design of dual mode power supply distribution circuit with detection and control functions
Authors: Wang Fengge , Fan Ji , Wang Baohua , Zeng Yuyun , Chen Xiaoming , Lu Ying , Wang Haiwen
Published: November 2022

Aiming at single mode of Underpan generator power supply, and the feature of being not meet the regular work of system under special working conditions, engine fuel exhaustion, unexpected faults, Design of Dual Mode Power Supply Distribution Circuit With Detection And Control Functions which includes Battery power, power distribution module, anti-diode, generator detection module, underpan on-off control module, Battery anti-loss detection module was proposed .The tests show that the generator power supply mode and battery power supply mode can convert freely, and the Supply Distribution Circuit is stable and reliable.
A quick Heuristic and a general search algorithm for traveling salesman problem
Authors: Wang Chao , Wang Deguang , Jin Chun
Published: November 2022

This paper puts forward a constructive heuristic algorithm called the method of inserting the minimum neighbor edge from outside to the center (IMNEFOTC) that can be applied to solve large-scale and ultra-large-scale travelling salesman problems. Through it and the randomized greedy heuristic algorithm (RGH) which greedy heuristic algorithm is modified, a general meta-heuristic search algorithm framework is built. The general search algorithm (GSA) is based on a set of initial solutions, and continuous 2-opt operations are performed, so as to search for solutions in better quality. The data from the experiment reveals that the performance of IMNEFOTC is better than the traditional greedy algorithm, and the GSA can obtain a pretty satisfactory solution in a reasonable range of time.
Floral constituents of the Australian tar tree,
Authors: Park Soo Jean , Cheesman Jodie , Cameron Donald N. S. , De Faveri Stefano G. , Taylor Phillip W.
Published: November 2022

Floral constituents of the Australian tar tree, Semecarpus australiensis, distributed in Melanesia and Northern Australia, were extracted with solvent, and analyzed by gas chromatography-mass spectrometry. The main constituents were 16- and 18-carbon fatty acids and their ethyl esters. Amongst the 67 identified compounds, zingerone was detected in minute quantity, providing the chemical basis for previous observations of fruit fly attraction to the flowers. The present study is the first to report the chemical profile of tar tree flowers.
The classifiability scale
Authors: Holz Christoph
Published: November 2022

In many languages, nouns need a numeral classifier to combine with number words or quantifiers. Even though
languages may have an elaborate system of numeral classifiers, there usually are exceptional nouns that combine directly with
number words. This paper deals with the following questions: Which nouns trigger a numeral classifier when counted? Which nouns
are more likely to occur without an additional classifier in a numeral context? Data from 32 languages reveal a classifiability
scale of nouns depending on their semantics. The more animate a noun, the more likely is the occurrence of a classifier. With
inanimate nouns, classifiers often may or must be omitted. The investigation extends to units, with units of time being much more
likely to be accompanied by a numeral classifier than other units. These findings are surprising in the light of the predominant
view that numeral classifiers are individuating units in languages where nouns appear to be uncountable mass nouns. I discuss
several approaches, of which animacy and the form-frequency correspondence principle are most promising.
Classifiers in Dimasa and (in-)definite marking
Authors: Evans Jonathan P.
Published: November 2022

Dimasa (ISO 639-3 dis) is a Bodo-Garo language within the Tibeto-Burman family of languages. Like other Tibeto-Burman languages of Northeast India, it has a system of numeral classifiers which occur prefixed to their respective numerals. Across the dozen or so languages of Bodo-Garo, it has been noted that the classifier-numeral word can be placed either before or after the counted noun. The existence of numeral classifiers, as well as theclf-numorder may have arisen in this area due to contact with Tai languages during the Ahom kingdom period from the 1200’s to 1800’s. In the Tai languages, classifiers precede the number “one”. By comparing occurrences of classifiers in Dimasa texts, it can be seen that the order Nclf-numcorresponds to definite nouns, while the orderclf-num nmarks indefinites. In addition to classifier placement, Dimasa definiteness is also marked by demonstratives, case marking, topic marking, and/or combinations of these strategies.
Numeral classifiers in the Austronesian languages of Taiwan
Authors: Pan Chia-Jung
Published: November 2022

This paper is a typological exploration of the nominal classification systems found in the Austronesian languages of Taiwan, with special focus on their meanings, forms and functions within the Austronesian typological context. Based on Aikhenvald’s defining properties and classifications of classifiers (2000, 2017, 2019, 2021, forthcoming), the Austronesian languages of Taiwan investigated in this study display a set of relatively small classifier systems consisting of numeral classifiers and other classifier-like terms, such as measure words and verbal action classifiers. Numeral classifiers can be free or bound morphemes. The choice of a numeral classifier is based on the semantic features of a noun referent, mostly involving ‘humanness’. Though not every referent has to be assigned to a numeral classifier, numeral classifiers always accompany numerals. In these languages, none of them have numeral classifiers without presupposing the presence of sortal classifiers.
Classifiers: Setting the scene
Authors: Aikhenvald Alexandra Y.
Published: November 2022

Classifiers are morphemes which occur under specifiable conditions and which categorise nominal referents in terms
of their animacy, shape, and other properties. The most widely represented type is numeral classifiers, which occur next to a
number word or a quantifier. Further types include noun classifiers, verbal classifiers, classifiers in possessive constructions,
and deictic classifiers. One language can have more than one type of classifier. In some, the same set of classifiers occurs in
several classifier contexts, corroborating the unity of the phenomenon. Classifiers categorise nouns, and have to be distinguished
from verbal action markers used to categorise and count actions. Classifiers have a variety of functions, and are never
semantically redundant. Classifiers mirror social attitudes and hierarchies, physical environment and means of subsistence, and
are susceptible to change in language contact situations. Contributions to this issue adress the systems and the functions of
numeral classifiers and also classifiers in multiple contexts across Asia and beyond, including Austronesian languages of Taiwan,
a selection of Tibeto-Burman (or Trans-Himalayan) languages, Zhuang, a Tai-Kadai language, and Kazakh, a Turkic language.
When support is “pawsed”: Increased attachment mediates the association between loss of support and pet bereavement during the pandemic
Authors: O’Connor Victoria L. , Vonk Jennifer , Compitus Katherine
Published: November 2022

The COVID-19 pandemic has introduced and exacerbated innumerable stressors for Americans. Pet ownership has been shown to help individuals cope with stress and loneliness. However, given the shorter life spans of most pets compared to humans, many pet owners inevitably dealt with pet loss and its associated grief during the pandemic. We surveyed 284 community and college participants that had suffered the loss of a pet during the pandemic. We asked these pet owners about their pandemic-related experiences over the preceding year with regard to the types of losses they experienced, whether they experienced isolation through quarantine and their perception of social support. We also measured their general attachment to pets along with the grief they felt as a result of pet loss. We hypothesized that greater loss, increased isolation, and reduced social support would lead to increased attachment to pets, which would intensify the experience of grief. Mediated regression analyses revealed a direct effect of loss on grief that was not mediated through attachment. Unexpectedly, greater perceived social support showed an indirect effect on grief through stronger attachment to pets. Results confirm prior findings that greater pet attachment leads to more intense pet grief, but the attachment was not intensified through loss of support social or increased isolation as predicted. It is important to recognize the substantial impact of pet loss, especially during stressful times, and this topic deserves further investigation, perhaps with a greater focus on the type of pet and pet-specific measures of attachment.
Latest data constraint of some parameterized dark energy models
Authors: Yang Jing , Fan Xin-Yan , Feng Chao-Jun , Zhai Xiang-Hua
Published: November 2022

Using various latest cosmological datasets including Type-Ia supernovae, cosmic microwave background radiation, baryon acoustic oscillations, and estimations of the Hubble parameter, we test some dark energy models with parameterized equations of state and try to distinguish or select observation-preferred models. We obtain the best fitting results of the six models and calculate their values of the Akaike Information Criteria and Bayes Information Criterion. And we can distinguish these dark energy models from each other by using these two information criterions. However, the ΛCDM model remains the best fit model. Furthermore, we perform geometric diagnostics including statefinder and Om diagnostics to understand the geometric behaviour of the dark energy models. We find that the six DE models can be distinguished from each other and from ΛCDM, Chaplygin gas, quintessence models after the statefinder and Om diagnostics were performed. Finally, we consider the growth factor of the dark energy models with comparison to ΛCDM model. Still, we find the models can be distinguished from each other and from ΛCDM model through the growth factor approximation.
A new two-dimensional fractional discrete rational map: chaos and complexity
Authors: Shatnawi Mohd Taib , Abbes Abderrahmane , Ouannas Adel , Batiha Iqbal M
Published: November 2022

In this paper, a new two-dimensional fractional-order discrete rational map with γth-Caputo fractional difference operator is introduced. The study of the presence and stability of the fixed points shows that there are four types of these points; no fixed point, a line of fixed points, one fixed point and two fixed points. In addition, in the context of the commensurate and incommensurate instances, the nonlinear dynamics of the suggested fractional-order discrete map in different cases of fixed points are investigated through several numerical techniques including Lyapunov exponents, phase attractors and bifurcation diagrams. These dynamic behaviors suggest that the fractional-order discrete rational map has both hidden and self-excited attractors, which have rarely been described in the literature. Finally, to validate the presence of chaos, a complexity analysis is carried out using approximation entropy (ApEn) and the C
0-measure.
A Smooth Nadir-Pointing Attitude Guidance law for Satellites Constrained by the Deviation of Sun-Pointing
Authors: Yang Zhibo , Qin Yang , Liu Jia , Sun Ningbo , Huo Da , Ji Haoran , Cong Qiang , Li Yanzhang
Published: November 2022

This paper proposes a novel nadir-pointing guidance method for satellites constrained by the deviation of sun-pointing, to ensure the attitude of the satellite steering smoothly. The main idea of establishing the expected attitude contains two steps. Firstly, establishing a temporary attitude according to the nadir direction and the normal direction of the ecliptic. Secondly, in order to reduce the deviation between the expected Sun-pointing axis and the Sun-pointing direction, the temporary attitude will be rotated along one Euler axis, and ensure that the expected nadir-pointing axis fixed in the nadir direction at the same time. The nadir-pointing method provided in this paper overcomes the singular phenomenon that the expected attitude of the satellite flips, without serious loss of Sun-pointing. In this way, the peak expected angular velocity and the peak power consumption will be greatly reduced.
Control Method for the Deorbit of Geostationary Satellite in the State of Gas-Liquid Mixing Variable Thrust at the End of its Service Life
Authors: Zhang ShuHua , Li JianPing , Yao Heng , Lei ZhongMou
Published: November 2022

By analyzing the gas-liquid mixing phenomenon in the thruster pipeline at the end of the service life of geostationary satellite, it is found that the gas in the pipeline leads to insufficient propellant combustion and unstable thrust output, which brings great difficulties to the orbit control of satellite. Aiming at the problem of thrust instability caused by gas-liquid mixing in the process of geostationary satellite orbit control, a joint orbit control method of normal mode + station keeping mode is proposed, which effectively solves the problem of deorbit at the end of the life of geostationary satellite in actual on orbit operation.
Optimization of Cooling Channel for Spark Plug Based on Conjugate Heat Transfer Simulation
Authors: Liu Yongchao , Li Yadong , Wang Tingting , Zhou Xiaoming
Published: November 2022

Air cooling channel is very important to avoid the ablation of ignition spark plug by reducing the temperature on the end face, and thus increase the service life of the spark plug. For a typical aero-engine ignition spark plug, coupled simulation model describing the flow in the air cooling channel as well as the heat transfer overall the spark plug has been established with a CFD software. Orthogonal experiments have been performed to analyze the influence of the design parameters on the air flowrate and end surface temperature On the basis of orthogonal experiment, the cooling channel is optimized by multi-factor analysis of variance The results demonstrate that: (1) The most important issue that influence the overall flowrate in cooling channel and the maximum temperature on the ignition end face is the number of holes on end face, and second one is the outlet diameter, while the influence of inlet diameter is not significant. (2) There is a better structural design for the cooling channel of the spark plug. The optimized air cooling channel increases the volume flow rate by 52.21% compared to the original scheme, which helps maintain the maximum temperature of the ignition end face of the spark plug below 368.2°C.
Preparation of TiO2/ZrO2 Composite as Photoanode of Ruthenium-Based Dye-Sensitized Solar Cells
Authors: Kusdiana Rochmat Fadillah , Aprilia Annisa , Safriani Lusi
Published: November 2022

Photoanode of dye-sensitized solar cell (DSSC) is an inorganic semiconductor layer with a nanoporous structure that has a function as a charge carrier transport layer and dye storage. Oxide semiconductor material such as titanium dioxide (TiO2) is widely used as a photoanode because of its wide band gap (3.2 eV) and high active surface area (80 m2/g), but TiO2 has low electron diffusion with high recombination (electron-hole pair pairing). To improve the electron diffusion and reduce recombination, TiO2 was modified with zirconia (ZrO2). The synthesis process was carried out using sol-gel method with variations of ZrO2 concentrations at 5 mol%, 10 mol%, and 15 mol%. Composite of TiO2/ZrO2 was then applied as a photoanode of DSSC. XRF results show that in all variations of ZrO2, the composites of TiO2/ZrO2 has been formed. Based on the results of UV-Vis spectroscopy, it was shown that the energy gap of TiO2/ZrO2 decreased as the increasing of ZrO2 concentration. The current density-voltage measurement was done to investigate the effect of ZrO2 addition to the TiO2 photoanode using light irradiation with power intensity of 100 mW/cm2. There is an increasing of photocurrent from 1.63 mA/cm2 of DSSC with TiO2 photoanode to 2.79 mA/cm2 of DSSC with TiO2/ZrO2 10 mol% photoanode. The highest efficiency obtained from DSSC with TiO2/ZrO2 photoanode is 1.15%. It was found that the presence of ZrO2 in the composite of TiO2/ZrO2 increased electron transport and reduced charge recombination to improve the photocurrent of DSSC.
The development of simple microcontroller-based QCM with some treatment on the crystal oscillator surface
Authors: Faizal Ferry , Maulana Mochamad Irfan , Wuled Lenggoro I. , Panatarani Camellia , Made Joni I
Published: November 2022

The low-cost quartz crystal microbalance (QCM) instrument with the microcontroller as the basis of the embedded system of the frequency counter was implemented. The system uses a quartz crystal transducer from the crystal oscillator component. The frequency shifting was observed and analysed in association with some experimental tests. The experiments such as ethanol evaporation, water vapor in the humidity chamber, and coating the surface with TiO2 particles had been conducted. The developed QCM instrument has shown the ability to measure the frequencies in response to the addition or reduction of mass on the surface of the crystal oscillator. These responses are caused by evaporation, humid condition, and deposited particle on the quartz crystal surface. The QCM was varied into two initial frequencies, 5 and 10 MHz. The 5 MHz system represents the proper “in range” frequency counters, inside a counting limit of the microcontroller up to 5.6 MHz. On the other side, the 10 MHz is an experimental development system. Both types utilise a D flip-flop frequency divider that made a microcontroller-based frequency counter and can count the frequency twice the limit. The more stable 10 MHz have shown promising potential application related to the surface interaction with other material and can hold thicker deposition on its surface with a better stability response than the lower frequency counterpart.
Development of A Two-storage Reservoir Operation Rules for Flood Control Case Study of Wonogiri Multipurpose Reservoir, Central Java, Indonesia
Authors: Jayadi R , Istiarto  , Pratiwi E P A , Windianita K
Published: November 2022

Wonogiri Reservoir, one of the large reservoirs in Indonesia, regulates water for flood control, irrigation, domestic use, and hydropower. It is located at the upper part of Bengawan Solo River Basin, Central Java. A closure dike has recently been constructed as a countermeasure against severe sedimentation that separates the reservoir into two parts, i.e., Sediment Storage Reservoir (SSR) and Main Reservoir (MR). A two-gate spillway was constructed in the SSR to facilitate sediment flushing and sluicing. During flood events, it controls reservoir water level jointly with the MR spillway. This brings the need for an update on the reservoir operation rules, especially on the gates opening of the new spillways to maintain the flood control performance. An assessment of reservoir routing simulation results was carried out by considering the overflow from SSR to MR, or vice versa with two options of Control Water Level (CWL), i.e. +135.8 m and +136.3 m. The flood control performance of the new reservoir operation rules was evaluated by considering the reservoir water level recovery, the maximum total outflow discharge, and the dam safety due to the risk of overtopping. These assessments give a foundation for the selection of CWL and the spillway operation to ascertain an optimal flood control of the reservoir.
Slope stability analysis during an earthquake in flow-slide affected area of Jono Oge
Authors: Andiny A N , Faris F , Adi A D
Published: November 2022

On September 28th, 2018, the earthquake with a moment magnitude (Mw) 7.5 due to strike-slip Palu-Koro Fault in Central Sulawesi caused a major geological failure. In the Jono Oge area, the earthquake-induced liquefaction and flow-slide occurred on relatively flat ground with an average slope of 2%. In this paper, the safety factor for slope stability analysis was determined by shear strength reduction caused by the earthquake at the potentially liquefied soil layer, varying peak ground acceleration values, and groundwater level conditions. This analysis evaluated the potential of ground movement occurrence in Jono Oge with the condition of soil layer pre and post the Palu-Donggala earthquake that happened in 2018 using GeoStudio Slope/W geotechnical software. The analysis was conducted on the cross-section of the soil layer based on three boreholes incorporating standard penetration test (SPT) data on the study area. The analysis results showed ground movement potential because of the seismic loads and groundwater level conditions. The lower the safety factor of slope stability, the higher the ground movement potential in flow-slide affected area. This ground movement potential could trigger the occurrence of flow-slide in Jono Oge area.
Liquefaction Potential Analysis and Mitigation at The Sediment Control Structures on Bangga River, Central Sulawesi
Authors: Fauzan  , Rifa’i A , Ismanti S
Published: November 2022

The Palu Earthquake in 2018 has triggered a debris flow incident in Bangga River. As a form of protection for similar disasters, it is planned to construct Sediment Control Structures in the Bangga River. The Bangga River area also has liquefaction potential that needs to be considered to ensure the structure’s stability. This study aims to perform liquefaction analysis at the Sediment Control Structure area. Liquefaction potential is calculated using the Simplified Method and Liquefaction Potential Index Method based on 15 bore-log data that includes SPT. Further analysis is conducted by calculating lateral spreading and settlement potential. Liquefaction potential is found in the Consolidation Dam area, leading to lateral spreading and settlement at the footing of the structure. The lateral spreading potential is found from a depth of 11 to 13 m, with the potential movement of 0.886 m and located only 1 m below the Consolidation Dam foundation. Mitigation planning is proposed by compaction method to increase the liquefaction resistance. The safety against liquefaction is achieved by increasing NSPT value of the vulnerable soil to be greater than 36. This increasing soil strength can reduce lateral spreading potential up to 95% and the settlement potential up to 89%.
Assessing Flood Hazard Index using Analytical Hierarchy Process (AHP) and Geographical Information System (GIS) in Stung Sen River Basin
Authors: Khoeun Chanseyma , Sok Ty , Chan Ratboren , Khe Sotheanea , Ich Ilan , Chan Kimsan , Oeurng Chantha
Published: November 2022

Flood is a water-related disaster that causes negative impacts on Human and societies. In Cambodia, flood has become more severe and frequent in most regions, especially, in the floodplain areas. This study aims to simulate the flood hazard index and vulnerability located in the Sen River Basin using the Analytical Hierarchy Process (AHP) method and Geographical Information System (GIS). GIS was applied for the estimated Flood Hazard Index (FHI) in which seven parameters were selected: Flow accumulation, Elevation, Density Drainage, Rainfall Intensity, Slope, Soil Type, and Land Use. Additionally, the relative importance of each parameter of physical factors has been compared in the pairwise matrix 7×7 to gain the weight value by AHP Method. The Flood Hazard Zones was classified into five classes from Very Low to Very High and were observed as Very low 6175 Km2, Low 4094 Km2, Medium 2002 Km2, High 818 Km2, and Very High 859 Km2. The FHI was verified with the flood hazard map from global surface water and Flood history from Google Earth Engine. Consequently, the results were found to be reasonable and adequate, revealing a realistic representation of hazards on the corresponding flood hazard map.
River Water Quality Implication after the Earthquake
Authors: Kong Leangkim , Nor Aznah , Hakim Mohd , Said NF. , Asanuma J.
Published: November 2022

The earthquake of 6.0 Magnitude occurred in the Ranua district of Sabah lasted for 30 seconds on 5th June 2015. This study investigated the various water quality parameters such as turbidity, color, dissolved oxygen, pH, electric conductivity, total dissolved solids, and so on from two monitoring stations (Bambangan and Kimolohing). The secondary data was requested from the Water Department of Sabah, where the Liwagu river is the downstream system of Mesilau. Through the temporal trace of each parameter, the water quality parameters showed an abrupt change one day before the earthquake. Consequently, around two weeks after the quake, it reached its initial state rapidly. After the earthquake, the mean turbidity is 436.25 NTU with a standard deviation of 1416.86 NTU. Its peak was on 17th June with 5550 NTU, total dissolved solids were 58.68 mg/l, and the electrical conductivity was 122.98 μs/cm at the Bambangan station, while it was 673.00 NTU with a standard deviation of 1869.90 NTU and it peaked on 17th June with 3750 NTU in the Kimolohing. The dissolved oxygen hit the lowest level of 3.27 mg/l on 17th June when 4.19 mg/l. The nitrate concentration increased to the maximum of 0.18 mg/l and 0.15 mg/l in the Bambangan, and the Kimolohing station, respectively. The metal concentrations also increased after the earthquake at both stations. However, alkalinity and hardness had decreased since 30th April before the earthquake and continued to decline until 14th August, when it reached the initial level. The value of pH and chloride did not seem to be affected by the earthquake, as the concentration maintained the average level.
Utilizing Google Street View for Rapid Seismic Vulnerability Assessment: Case Study in the City of Manila, Philippines
Authors: Evangelista M K , Aquino D H , Ramos J A
Published: November 2022

Earthquake Impact Reduction Study for Metro Manila (MMEIRS) estimated that around 40% of the total number of residential buildings within Metro Manila will either collapse or be affected by the M7.2 generated by the West Valley Fault. Need arises to evaluate the seismic vulnerability of structures in the area to enhance the city’s resilience to seismic hazards. Rapid seismic vulnerability assessments are typically conducted by means of sidewalk surveys. However, advances in digital technologies such as Google Street View (GSV) provide the potential to do remote assessments, particularly amid mobility restrictions brought about by the COVID-19 pandemic. This paper aims to demonstrate the usefulness of GSV in collecting data needed for rapid seismic vulnerability assessments through the case of buildings in the City of Manila. Six 300 m x 300 m blocks were evaluated using GSV for identifying seismic-related building parameters. Results show the ease of use of GSV in data collection on areas encompassing commercial and residential zones within the city and poses difficulty for blocks dominated by informal settlements. Among the challenges observed in formal zones include blockages in views due to fences, trees, and/or vehicles parked in front. For informal settlements, much of the buildings are not visible in GSV for evaluation thereby necessitating supplemental data collection. Overall, GSV demonstrates usefulness, and has the potential to speed up seismic vulnerability assessments in urban areas in conjunction with existing in situ assessments currently conducted.
Analysis of the Effective Length of Handil Channel for Tidal Irrigation at Palingkau Irrigation Area in Central Kalimantan Province for National Food Estate Program
Authors: Ramadhani E.E. , Sujono J. , Taryono
Published: November 2022

The handil irrigation system is a traditional water management system developed by local farmers and the government to irrigate rice fields using tidal power for supply and drainage. The canal with a width of 25 meters and a length of about 2 kilometres was developed to irrigate 1,397 ha of irrigated agricultural land in the Palingkau Irrigation Area. At high tide, freshwater enters the canal from the Kapuas Murung River, and drains into the river at low tide. After a long period of development of the area, sediment deposition and changes in channel cross-section occur so that the water system does not function optimally. For the sake of rehabilitation, an analysis was carried out to determine the effective canal length of the canal that is influenced by tidal water, considering channel capacity, tides and land elevation. Hydraulic analysis was performed by using HEC-RAS mathematical modelling. The results showed that tidal fluctuations could not irrigate two handil’s rice fields out of 8 existing handils. Canal rehabilitation in the form of increasing channel capacity is carried out by considering the length of the canal and the irrigation area irrigated, including its effect on improving water quality.