bluuebunny/crossref_metadata_2025 huggingface dataset:
Application of DBSCAN Algorithm in Data Sampling
Authors: Deng Dingsheng
Published: August 2020

Data sampling is to sample hidden, previously unknown knowledge and rules that have potential value for decision-making from massive data. Cluster analysis is an important research topic in the field of data sampling. How to extract the information and knowledge that people care about, unknown, and help to analyze the decision-making process from massive data is a problem that people urgently need to solve. In this paper, after using the genetic algorithm-based method to obtain a better initial clustering center, the DPDGA algorithm divides the data set according to the obtained initial clustering center point. For each local data set obtained by division, the parameters MinPts of each local data set are calculated, and then each local data set is clustered using the DBSCAN algorithm, and finally the clustering results of each local data set are merged. Aiming at the shortcomings of the DBSCAN algorithm, this paper proposes a DBSCAN algorithm that uses particle swarm optimization to divide data and uses the MapReduce model to perform parallel calculations. The DPDPSO algorithm first uses the particle swarm optimization algorithm to obtain the optimal initial clustering center, and then partitions the data set according to the optimal initial clustering center. After partitioning, the DBSCAN’s own k-dist graph is used to determine the ε and MinPts, finally merge each partition according to certain rules, and merge data points that may be mistaken for noise points. Research shows that when the amount of data reaches about 7M, the clustering method used in this article may take up to 1 hour. If the number of iterations is less, the time it takes will be less.
Chaotic Time Series Prediction Using LSTM with CEEMDAN
Authors: Yanan Guo , Xiaoqun Cao , Bainian Liu , Kecheng Peng
Published: August 2020

Chaotic systems are complex dynamical systems that play a very important role in the study of the atmosphere, aerospace engineering, finance, etc. To improve the accuracy of chaotic time series prediction, this study proposes a hybrid model CEEMDAN-LSTM which combines Complete Ensemble Empirical Mode Decomposition with Adaptive Noise (CEEMDAN) and long short-term memory (LSTM). In the model, the original time series is decomposed into several intrinsic mode functions (IMFs) and a residual component. To reduce the difficulty of predicting chaotic time series and provide a high level of predictive accuracy, the LSTM prediction model is built for all each characteristic series from CEEMDAN deposition. Finally, the final prediction results are obtained by combining all the prediction sequences. To test the effectiveness of this model we proposed, we examined the CEEMDAN-LSTM model using the Lorenz-63 system. Further compared to Autoregressive Integrated Moving Average (ARIMA ), Support Vector Regression (SVR), multilayer perceptron (MLP), and the single LSTM model, the results of the experiment show that the proposed model performs better in the prediction of chaotic time series. Besides, the hybrid model proposed in this paper has better results than the LSTM model alone. Therefore, hybrid models based on deep learning methods and signal decomposition methods have great potential in the field of chaotic time series prediction.
The bioclimatic extent and pattern of the cold edge of the boreal forest: the circumpolar taiga-tundra ecotone
Authors: Montesano Paul M , Neigh Christopher S R , Macander Matthew , Feng Min , Noojipady Praveen
Published: August 2020

Current configurations of forest structure at the cold edge of the boreal may help understand the future of ecosystem functioning in high northern latitudes. The circumpolar biome boundary at the boreal (taiga) forest and tundra interface is an ecological transition zone (taiga-tundra ecotone; TTE) experiencing changes that affect its forest structure. We accounted for the TTE’s horizontal forest structure with an estimate of its extent and pattern as represented by tree canopy cover (TCC). We quantified TCC patterns with an algorithm that describes its spatial gradient, and summarized landscape patterns of structure to represent heterogeneity, capturing abrupt, diffuse, and uniform forest at mesoscales. We used these landscape patterns to constrain the spatial extent of sparse and open canopy forest, and non-forest (forest-adjacent) edge that defines the TTE extent. The resulting map of the TTE extent is based on forest structure spatial patterns resolved at 30 m, highlights structural variability across landscapes, and helps distinguish tundra from boreal domains. We classified 14 594 landscapes as those associated with the TTE within a circumpolar bioclimatic envelope (11.575 million km2), where 44.83% of the area of these landscapes were forest and non-forest edge, yet 36.43% contributed to the TTE extent. We report the overall extent of the TTE (3.032 million km2) across North America and Greenland (53%), and Eurasia (47%), where 0.697 million km2 is non-forest edge, 0.549 million km2 is sparse forest, and 1.787 million km2 is open canopy forest. Diffuse forest landscapes dominate the TTE (79%), and abrupt landscapes (∼19%) indicate portions of the TTE where sparse forest and non-forest edge are the prevailing structural patterns. This account of the TTE quantifies the area of the cold edge of the boreal forest where previous global estimates show high discrepancies, and can help target monitoring and prediction of circumpolar dynamics.
Thermodynamic vs statistical entropy production in thermostatted Hamiltonian dynamics
Authors: Ramshaw John D
Published: August 2020

Sufficient conditions were recently established for the rates of thermodynamic entropy production and phase space volume contraction to be identically equal in thermostatted Hamiltonian systems in non-equilibrium steady states (Ramshaw 2017 Phys. Rev. E
96 052122). This equality has previously been interpreted as a statistical analogue of the second law of thermodynamics (SLT). However, that interpretation is unjustified because the volume contraction rate represents the production rate of the statistical entropy of the system and thermostat together, which differs in general from that of the Hamiltonian system itself. This logical lacuna is remedied by identifying two further conditions which combine with the previous conditions to imply a proper statistical analogue of the SLT. The first of these new conditions can simply be imposed a priori, whereas the second, like ergodicity and mixing, involves the asymptotic statistical properties of the dynamics as t → ∞. The latter condition seems likely to be analytically intractable in general, and therefore to require numerical investigation and confirmation in systems of practical interest.
Hydrocarbon Penetration in Multi-Porosity Soil
Authors: Rashid M F A , Alias N , Ahmad K , Sa’ari R , Ramli M Z , Shahrin M I , Ibrahim Z
Published: August 2020

Groundwater contamination is crucial, particularly due to hydrocarbon liquid leakages. Additionally, the vibration impact affects the migration of hydrocarbon through the subsurface soil to the groundwater surface which is causes by the dynamic stress that is imposed on the soils. Therefore, this paper presents the investigation and discussions on the penetration of Light Non-Aqueous Phase Liquid (LNAPL) in vibrated unsaturated double-porosity laterite soil with 30% moisture content. The apparatus used for this experiment are a vibrating table, acrylic soil column, mirror, LNAPL and a Nikon D90 digital camera. The LNAPL migration pattern in laterite soil was monitored and recorded using a digital image processing technique (DIPT) at certain time intervals. The images were processed using Surfer software and Matlab routine to plot the LNAPL hue-saturation-intensity (HSI) values. As a result, the migration rate of LNAPL decreased with the impact of vibration towards the soil due to the rearrangement and porosity of the soil structure and this was found to affect the speed of liquid penetration.
A journey towards sustainability: a review on sustainable development implementation in Malaysia
Authors: Idham Bin Mohd Yusof Mohd , Ariffin Mariani
Published: August 2020

Since its inception, Malaysia is committed in developing the country. As a member of the United Nations (UN), Malaysia has always becoming the frontrunner in fulfilling the development agenda as proposed by various regional and international organizations. The government ever since has embracing the concept of sustainability through its national framework. This can be seen when this country adopting the Local Agenda 21 (LA21), Millennium Development Goals (MDGs) and now the Sustainable Development Goals (SDGs). In 2017, Malaysia is among the earliest countries to present the Voluntary National Report (VNR) in the SDGs progress. With a participatory from various parties, this was done at the Higher Level Political Forum (HLPF) in the UN. This has made Malaysia as a good example among the developing and Islamic countries. It serves as the best platform for Malaysia and the other members to share theirs’s best practice and learn from each other as a community of practice. This paper seeks to examine sustainable development implementation in Malaysia through review of literatures and content analysis. It aims to analyze the sustainability efforts by identifying the themes of the development, the attention of the government towards the sustainability, its various policies, the involvement of actors and the challenges throughout its implementation. It is not easy for the country to make its people aware on the meaning of sustainability. It requires political commitment and integrated actions by its key players as the driving forces. Sustainable development will always be the focus for Malaysia as this global effort will make this country a better place for the future generation.
Variations in physico-chemical parameters and Chl-a concentration in Setiu Wetlands lagoon during the northeast and inter-monsoon seasons 2018
Authors: Suhaila Ismail Shaharul , Hafiza Ramli Nur , Mat Semawi Nurhayati , Azrinkhuzaini Abdul Kadir Mohd , Nazila Ali Ahmad
Published: August 2020

This study presents the seasonal changes of physico-chemical parameters and chlorophyll-a (Chl-a) concentration in Setiu Wetlands lagoon during the NEM (February 2018) and inter-monsoon (April 2018) seasons. The Chl-a and physico-chemical parameters of water temperature, dissolved oxygen (DO), pH and salinity were investigated for both surface and bottom waters at 3 sampling sites that are located in the upstream and downstream of the lagoon. The was a strong seasonal signal and spatial gradient in physico-chemical parameters within the Setiu lagoon. In February, when the strong northeast monsoon (NEM) prevailed, the surface and bottom waters of the lagoon were dominated by high pH and low water temperature, DO and salinity. As the weaker inter-monsoon dominated in April, the study area was characterized by low pH and high water temperature, DO and salinity. While the seasonal variation in physico-chemical properties of Setiu lagoon is well described, Chl-a concentrations varied between seasons and sampling locations. Chl-a showed an increased or only a slight change in the downstream stations but recorded a significant decreased in concentrations in the upstream station from the NEM to inter-monsoon season. Analysis of seasonal relationships clearly indicated the interchangeable negative and positive correlations of Chl, DO and salinity. These results suggest the influence of other environmental factors of the lagoon (e.g., nutrient enrichment, tidal and freshwater influx) that vary with seasons which require more detailed investigation.
A Proposed Model of Fishpond Water Quality Measurement and Monitoring System based on Internet of Things (IoT)
Authors: Ismail Rosli , Shafinah Kamarudin , Latif Kamil
Published: August 2020

Aquaculture in Malaysia is now being promoted as an important engine of growth and eventually becoming the pillar of the economy of the nation. However, healthy fish production requires intensive care, and to ensure a stable and healthy production environment inside the fishpond is a challenging task. While cultivating aquatic organisms, water quality is a critical factor. It depends mainly on various parameters such as dissolved oxygen, ammonia, pH, temperature, salt, nitrates, carbonates, etc. In most places, this testing is performed by fishpond farmers manually or by researchers through laboratory testing where there is no real-time monitoring. Today, with the advancement of the Internet of Things (IoT) and sensors, the technology is reaching the ground level with its application uses in agriculture and aquaculture. It is highly desirable to have an IoT - based automated system that can continuously measure and monitor fishpond with optimum utilization of resources. This paper proposes a model for real time measurement and monitoring system based on IoT technology for measuring and monitoring the water parameters in fishpond. We used a qualitative method to investigate perceptions, experiences, and ideas of fishpond farmers in order to propose the model. With the help of the proposed model, the quality of water can be continuously measured and monitored to ensure the growth and survival of fish in pond. As a result, preventive action can be taken in a timely manner to minimize losses and increase productivity.
A study to expose quail eggs for two different periods of incubation with low-intensity magnetic flooding on the growth of chicks and their productive performance
Authors: Khaleel Ibrahim Firas , Seddiq Mohmood Bakar , Mohamad Shukri Malik
Published: August 2020

An experiment was conducted in the fields of the poultry unit - Livestock Division - Nineveh Research Department, to find out the effect of using low-intensity magnetic flux (110 Gaos) in two periods of incubate quail eggs, on the growth and production performance of the resulting birds, the results showed a significant increase (P ≤0.05) for the magnetic flux treatment on control treatment for hatchability% and fertility%, the percentage of dead embryos decreased significantly (P ≤0.05) for the second exposure period treatment than the control treatment, the two magnetic exposure treatments were significantly superior (P ≤ 0.05) to control treatments in the body weight at one and four weeks age (g), weight gain (g) and food conversion ratio (g/g). The magnetic exposure treatment also achieved a significant decrease (P ≤0.05) for the number of days to reach sexual maturity (or the days to obtain 5% egg production) and for food consumed / kg. The two magnetic treatments were also significantly superior in food conversion ratio (kg feed / kg egg) for the eight-week period of egg production.
First report of the parasitoid wasp Platygaster oebalus (Hymenoptera: Platygastridae) from Iraq
Authors: Kareem Ali A. , Lahuf Adnan A. , Aljaafari Raad K. , Buhl Peter N.
Published: August 2020

The parasitoid wasp Platygaster oebalus was collected from Karbala city in April 2019 and recorded for the first time from Iraq.
Effect of melatonin in adult quail males exposed to oxidative stress induced by H2O2
Authors: Taha Ahmed T. , Al-Jumaily Tareq KH , Al-Samrai Muna K.
Published: August 2020

In the dark, the pineal gland secreted melatonin hormone after produced from tryptophan that is Responsible for organizing many vital functions such as Wake up and sleep, circadian rhythm, Immune response and reproduction. As well as that Melatonin act as antioxidant and inflammatory.

Thirty-six of 45 days-old Japanese quail male randomly divided to four treatments nine replicates per each. The control treatment consisted of the basal diet and normal water, 2nd treatment of (1%) hydrogen peroxide in drinking water.3rd and 4th treatment the ratio supplemented with (20 mg melatonin / kg diet) with or without(1%) hydrogen peroxide in drinking water. At 28 days, hematological parameters, antioxidant measurement determined and testes histological assessment.

From the results noted a significant reduction in the total counting of red blood cells (RBC) and the relative weight of the testicles with a deterioration in antioxidants status, represented by a significant increase in MDA level and a significant decrease in GSH level of with H2O2 treatment . The supplemented of melatonin led to a decrease in the total number of WBC, PCV, and the concentration of Hb. Moreover, the treatment with the use of melatonin led to an improvement in antioxidants indicators represented by an increase in the level of GSH and a decrease MDA level. As the fourth treatment did not record significant differences compared to the first treatment. Adding melatonin at 20 mg melatonin / kg diet lead to significant improvement in area of germinal layer and its thickness.
Detection Beta-lactam residues in imported and local dairy products in Mosul city
Authors: Albanna Ayman , Fadhel Mazin N. , Al-Shaker Yusra M. S.
Published: August 2020

Two hundred and forty samples of milk products were examined for ß-Lactam antibiotics residues by using a quantitive technique (Sandwich-ELISA). Basically, the study comprised three different dairy farm animals (buffalo, cow, and sheep), the samples were collected from Mosul city farms, and compared to imported dairy products from exotic sources. Apparent ß-Lactam residues were found most of the milk products, considerably local and imported products. In terms of local milk products were 50% of cow, 60% of sheep, and 20% of buffalo mostly free from antibiotic residue. In contrast, imported milk products were 90% of cow, 70% of Sheep, and 10% of buffalo, also free from antibiotic residue and suitable for human consumption. However, there were many samples of milk products contaminated with ß-Lactam residue, in particular, buffalo products were high concentrations of ß-Lactam compounds, regardless of whether local and imported products. With respect to cow products, 50 % of local samples compared to 10 % of imported samples were contaminated with ß-Lactam residues. Whereas in sheep products, 40% of local products compared to 30% of imported products were high concentration of antibiotic residues. Surprisingly, for all samples of this study, it has been noticed within the same product, the concentration of ß-Lactam was high level in cheese and cream compared to milk raw, however, in yogurt were decreased sharply 45% compared to cream, cheese, and milk respectively.
Effect of Organic and Inorganic Fertilizers on Growth and Yield of Hybrid Cucumber Cucumis sativus L. Grown under Unheated Plastic House
Authors: Jawad Muharram Al-Bayati Hussein
Published: August 2020

The experiment was conducted in one of the unheated plastic houses of the Department of Agriculture and Landscape Design / College of Agriculture and Forestry / University of Mosul during the agricultural season 2018 to study the impact of two factors: The first addition of organic fertilizers decomposed poultry residues fertilizer (Atalpolina) 100 kg. 1000 m2 and rice residues fertilizer 10 t. ha−1 and sheep residues fertilizer 10 t. ha−1 and compound chemical fertilizers 300 kg. ha−1, In addition to the comparison treatment, the second: Two cucumber hybrids Sultan and Zain. The experiment applied in the field of split system with in randomized complete block design RCBD with three replicates. Analysis statistically the results were as follows: The hybrid Zain increased plant height, number of leaves, leaf area per plant, length of fruit and number of fruits per plant, while the hybrid Sultan increased fruit weight. The inorganic treatment caused decreased number of days for flowering plants and increased plant height, number of leaves, leaf area pre plant, and number of fruits per plant, yield per plant, early fruits yield and total yield of fruits comparison with control treatment. The interaction of treatments the addition of inorganic fertilizers with Zain hybrid gave the lowest number of days to flowering the plants and increased plant height, number of leaves per plant, leaf area per plant, number of fruits per plant, yield per plant and number of fruits per plant. The treatment of sheep waste in the same hybrid increased early fruits compared with other treatments.
Effect of adding different levels of vitamin B7 to the diet on some blood for the of parameters Japanese quail (Coturnix coturnix japonica ) exposed to oxidative stress
Authors: Hamza Yasser Al-Awadi Ibrahim , Abdul-Lateef Ali Al-Nadawi Nihad
Published: August 2020

This experiment was conducted at the poultry farm of the college of Agriculture, University of Al-Qasim Green for the period from 26/9/2019 to 8/11/2019. The study was aimed to the effect of adding different levels of vitamin B7 to the diet on some blood for the of parameters Japanese quail (Coturnix coturnix japonica ) exposed to oxidative stress. in the experiment, 300 unsexed Japanese quail birds were used. The eggs were obtained from the Agricultural Research Department in Abu Ghraib and the eggs hatched in Al-Nasr hatchery in Babylon province. They were raised together until the age of 8 days and then were randomly distributed to 5 treatments with 3 replicates each treatment ( 20 birds / replicate). The oxidative stress was induced by adding 0.5% H2O2 to drinking water and the experimental treatments were as follows: The first treatment: a negative control treatment that is free of vitamin B7 or H2O2. The second treatment: a positive control treatment that was free of adding vitamin B7 + water with H2O2 added by only 0.5%. The third treatment: adding vitamin B7 at a concentration of 500 micrograms/kg feed + water added with H2O2 at a concentration of 0.5%. The fourth treatment: adding vitamin B7 at a concentration of 600 micrograms/kg + water with H2O2 added at a concentration of 0.5%. The fifth treatment: adding vitamin B7 at a concentration of 700 micrograms/kg + water with H2O2 added at a concentration of 0.5%. The treatment lasted from 8 to 42 days. The experiment included the study of the following traits: red blood cell count, white blood cell count, percentage of Haematocrit (%), Hemoglobin concentration, percentage of the heterophile cells (%), percentage of lymphocyte cells (%) and H/L ratio. The results indicated that the fourth and fifth treatment (adding of 600 and 700 micrograms of vitamin B7 / kg feed) showed a significant improvement (p≤0.05) in the numbers of red blood cells compared to the first treatment (negative control) and the second treatment (positive control), as for the Haematocrit and haemoglobin concentration The adding treatments (third, fourth, and fifth) significantly differed (p≤0.05) on the first treatment (negative control) and the second treatment (positive control) at the age of 42 days. All treatments of adding vitamin B7 recorded a significant decrease (p≤0.05) in the numbers of white blood cells, percentage of the Heterophil cells (%) and increase in Lymphocytosis cells and decrease in the percentage of H/L cells as compared with the second treatment (positive control). It is concluded from the present experiment that adding of the vitamin B7 at a concentration of (600, 700 μg/kg feed) to the diet can lead to improving some blood parameters for Japanese quail.
The effect of using three different levels of Fish Meal on growth criteria and feeding efficiency in Cyprinus Carpio.
Authors: Al-Bachry Waleed Sami J. , Abd Al-Jabbar Ibrahim Ali , Al-Humairi Kadhim O. M.
Published: August 2020

Study the effect of three different levels of adding a fishmeal protein concentrate on the growth rates of the common carp fish (Cyprinus carpio) through laboratory experiments, which lasted for 40 days. 27 common carp fish were used with a weight of 2 ± 93.27 g and distributed over 9 concrete ponds with a capacity (300) liters, according to three treatments T1, T2, and T3 distributed in three replicates for each treatment, and put 9 fish (3 fish / repeated). The fish were fed on three different diets, with a protein concentrate ratio of 23%, 15% and 10%, respectively. Measurement of weight, relative specific growth rates and food conversion rates. The best total weight gain increase for the second treatment was recorded (35.478 ± 2.29 g). The best relative growth rates were (37.769 ± 2.51) and specific (0.346 ± 0.02)% g/day and protein efficiency ratio ( 2.365 ± 0.23) for the second treatment also, and significant differences were recorded at (P <0.01) on the two treatments T3; T1 in all the studied characteristics.
Growth and Yield Response of Basil (Ocimum basilicum L.) to Different Rates of Urea Fertilizer Under Field Conditions
Authors: Sabah Alhasan Ali , Kadhem Abbas Majeed , Al-Ameri Maryam , Tareq Al-Ameri Dalal
Published: August 2020

Basil plant (Ocimum basilicum L.) is aromatic and medicinal plants, cultivated for producing essential oil, and utilizing in culinary, biopesticides, and pharmaceutical productions. Notwithstanding, basil production can be used in different markets. Nitrogen deficiency is the main factor influences basil production in the world. Thus, this study was performed during the summer season of 2019 to evaluate the impact of the application of urea fertilizer (applied at seven rates; 0, 20, 40, 60, 80, 100, and 120 kg N/ha) on chlorophyll, agronomic traits, seed yield, and essential oil production. Using a moderate rate of urea fertilizer is proposed to be sufficient for some agronomic traits. Moreover, a nonlinear-relationship between essential oil and urea fertilizer rate was found. This study”s results proved that utilizing urea fertilizer at a moderate rate can increase agronomic traits and essential oil of basil.
Effect of essential oil of colocynth, Citrullus colocynthis and spearmint, Mentha spicata against the khapra beetle, Trogoderma granarium Everts (Coleoptera: Dermestidae)
Authors: Tareq Al-Ameri Dalal , Hamza Abbas K. , Hasson Hassan Bassim , Sabah Alhasan Ali
Published: August 2020

Khapra beetle Trogoderma granarium is considered to be the most severe primary pests, affected both the quality and quantity of wheat during storage. Therefore, khapra beetle is a serious problem in developing and developed countries. A laboratory study was performed to evaluate the influence of the essential oil rate of spearmint Mentha spicata and colocynth Citrullus colocynthis against khapra beetle T. granarium to determine the mortality rate of egg, larvae, pupa, and adults. Throughout the experiment, increasing the doses of essential oil of spearmint resulted in the highest rate of mortality of the khapra beetle egg, larvae, and pupa compared with increasing the rate of essential oil of colocynth. Thus, a linear relationship was found between the mortality rate of khapra egg, larvae, and pupa with the essential oil rate of spearmint. The highest mortality rate of adults (94%) was obtained by applying 50 µL of spearmint. In contrast, the highest concentrations (40 and 50 µL) of essential oil of colocynth showed the lowest mortality rate of khapra beetle adults. This study suggested that the essential oil of spearmint could be utilized as potential control agents for stored-product insects in wheat.
Application progress of scour-abrasion resistant materials of hydraulic concrete
Authors: Xu Tao , Ma Yu , Wang Yuanli , Tao Jianqi , Li Xiulin
Published: August 2020

As the concrete surfaces of the sluice structure in the water conservancy and hydropower engineering would often suffer from the erosion of high speed sandy flow or water flow with bed load, there will often appear different degrees of wear and cavitations damages after a certain time of operation. Therefore, it is especially important to use the materials with high performance in resisting erosion and abrasion. Based on analyzing the abrasion damage mechanism and form of concrete, this paper mainly summarizes the research and application of scour-abrasion resistant materials, introduces the new development of scour-abrasion resistant materials, and finally provides an effective way of solving the impact of high silt-laden water erosion.
A Comprehensive Evaluation Model of Dam Failure Consequences Based on Combined Weighted Cloud Model
Authors: Xiong Fangjin
Published: August 2020

In order to solve the uncertainty and fuzziness of various factors, the cloud model theory is introduced to establish evaluation indexes from four aspects of life loss, economic loss, social impact and environmental impact. AHP and grey correlation method are applied to subjective and objective weight respectively, and a combination weight based on cloud model is proposed the evaluation model of dam break consequence. According to the evaluation index system and evaluation standard of dam breach, the cloud model parameters of different accident levels under the evaluation index are determined in the model; the combined weight of each index is calculated based on AHP and correlation degree method, and the comprehensive evaluation model of dam breach consequences is constructed. Taking five reservoirs in Jiangxi Province as an example, the results show that the model is effective and feasible, which provides a new way for the comprehensive evaluation of the consequences of dam break.
A Brief Analysis of Green Construction of Prefabricated Building Based on Guide Frame Climbing Lifting Platform
Authors: Liao Chenya , Li Shuxun , Chen Shuyuan
Published: August 2020

With the development of the construction industry and the vigorous support of national policies, prefab building has become the trend of future development of construction industry, which also makes the use of mechanical equipment in construction gradually enriched. Among them, the guide frame climbing lifting platform belongs to the building elevation construction equipment, which is more efficient in the construction process of prefabricated building. Its main characteristic is to reduce the construction personnel’s allocation, and the construction personnel’s burden, to ensure the quality and efficiency of construction, and to ensure that the safety of construction personnel played a huge role. It has played a great role in ensuring the safety of construction personnel and so on.
Research on propagation law of one-dimensional stress wave in jointed rock mass under in-situ stress
Authors: Dong Qian
Published: August 2020

The propagation law of stress wave in jointed rock mass under in-situ stress has important engineering significance on blasting excavation and protection engineering design of deep rock mass. Based on theoretical analysis, the propagation law of stress wave across multiple nonlinear deformation joints under the initial stress is studied. Firstly, the propagation equation of stress wave across multiple nonlinear joints considering the influence of initial stresses is established, through the discontinuous deformation method (DDM) and the recursive analysis method of stress wave in time domain. On this basis, parametric studies are conducted for the effects of stress wave propagation, such as initial stress, the amplitude of stress wave, the distance and the number of joints. The results show that the existence of initial stress will affect the propagation of stress wave, the geometric distribution of joints, such as spacing and number, can also cause the change of stress wave transmission coefficients, and the amplitude of incident wave varies can also lead to the change of stress wave propagation.
Reservoir dam operating risk dynamics modelling for safety control in the emergency response process
Authors: Shen Guangze , Lu Yi , Zhang Shichen , Xiang Yan , Sheng Jinbao , Fu Jilei , Fu Shan
Published: August 2020

As revealed by the dam break accident investigation statistics, flawed organizational behavior determines the safety level of the reservoir dam. Its operating risk revolution process involves water, disaster, relief material dispatching, information interaction, and so on. The multiple information transferring mode and dynamic processes perform with the characteristics of the social-technical system, but little prior research on the risk causality can be found in such a view. The traditional risk analysis and assessment techniques based on linear accident model and the partial probability calculation cannot effectively satisfy the requirements for dam-break emergency decision-making in a dynamic and systematic way. Based on the system dynamics approach, this study proposed risk dynamics models aiming for risk interaction mechanisms involving organizational, human, and technical system factors leading to dam break. The models guided the development of a quantitative risk assessment tool to integrate relevant professional modules and data. The derived policy suggestions which guarantee the life and property of downstream residents can improve the abilities of dam operating management organization for more effective responses under emergency circumstances.
Study on Bearing Capacity Influence Factors of the PBL Shear Connector
Authors: Qingxuan Shi , Fengzhu Yang , Jiangran Guo
Published: August 2020

In order to study the main influencing factors of the ultimate bearing capacity of the PBL connector, the large-scale nonlinear finite element analysis software ABAQUS was used to establish the solid model of the PBL connector, and the accuracy of the model was verified by comparison with the test results. Based on this, the main influencing factors of the ultimate bearing capacity of PBL connectors are analyzed. The results show that it is feasible to apply ABAQUS to the finite element analysis of the mechanical properties of PBL connectors, which can be assisted by experiments and empirical formulas; The concrete strength, the diameter of rebar and the number of holes have a significant effect on PBL connectors’ force, but the diameter of holes has little effect.
Analysis of the Influence of Bridge Piers on River FlowII-Computation of Bridge Crossing Choking
Authors: Deng Chunyan , Ge Hua , Long Rui , Yuan Yuan
Published: August 2020

The analysis of the impact of pier backwaters is very important in bridge design. The composition of the bed sand across the river, the shape of the pier, the hydraulic gradient of the channel, and the water resistance of the pier all have an impact on the water level backwater height and backwater distance. Considering the actual situation of the project, the influence of piers on flood discharge is analysed and calculated by different backwater empirical formulas. The results show that the calculation results of the formulas are not far apart. Considering the most unfavourable situation, the calculation results of Cao Ruizhang formula of the Chinese Academy of Railway Sciences are selected as the final results. Combined with the analysis of water resistance, the construction of the project has little impact on the flood discharge of the river.
PCA-NARX Time Series Prediction Model of Surface Settlement during Excavation of Deep Foundation Pit
Authors: Ma Qingwen , Liu Sihan , Zhao Xianchang
Published: August 2020

In order to ensure that the excavation of the foundation pit can proceed smoothly in complex environment, the deformation prediction is particularly important. Because the traditional model can not accurately predict the surface settlement when the external environment changes, so the PCA-NARX foundation pit settlement prediction model is proposed. The principal component analysis(PCA) method is used to analyze the main components that affect the surface settlement and use them as parts of the external input to dynamically predict the surface settlement. Combined with Beilong Lake Foundation Pit Project in Zhengzhou, the applicability and accuracy of the model are evaluated. The results show that: (1) Comparing with the prediction results of BPNN model, NAR model and NARX model, PCA-NARX model has higher accuracy, the mean square error is only 0.1677. (2) Comparing with NARX model without PCA method, PCA-NARX model can achieve higher accuracy in the same training time, and the accuracy is improved by 12.89%, so it is more effective to predict the surface settlement during excavation. (3) The prediction results of PCA-NARX at different monitoring points also performed well, which means that it can be applied to the prediction of other monitoring contents of the foundation pit.
Time Iteration for Service Life Prediction of Concrete Structure in Marine Environment
Authors: Jiang Qiongming , Ji Xuekuan , Nong Zhonglin
Published: August 2020

On the basis of chloride diffusion model, the time-varying and randomness of chloride diffusion in concrete are considered, Based on the reliability method, the service life of cross sea bridge structure can be predicted by the double cycle iteration of reliability and service life, and the service life of concrete of cross sea bridge structure can be directly calculated by the double iteration. In order to reduce the iterative calculation, through the improvement of the time iteration strategy, the tangent slope is replaced by the cut line slope, which not only makes the iterative convergence fast and accurate, but also solves the problem of service life and It is difficult to derive the implicit function of reliability.
Analysis of seismic performance of gravity dam based on ultra-high performance concrete reinforcement
Authors: Shi Junfei , Ma Tianxiao , Gao Lingang
Published: August 2020

Damage and crack of gravity dams under earthquakes directly affect the dam’s safety. Ultra-high performance concrete has high strength and durability. Whether to replace steel bars for seismic reinforcement becomes the focus of consideration. In the paper, the plastic damage model of ultra-high-performance concrete is established. Taking the gravity dam section as an example, referring to the design concept of the “gold coated silver” gravity dam, three different forms of seismic-reinforced schemes of ultra-high-performance concrete in weak areas of the dam are presented and analyze damage time histories. The calculation results show that the application of ultra-high performance concrete for reinforcement can greatly reduce the damage of the dam and improve the seismic performance of the dam. The study suggests that proper reinforcement measure can be taken according to the conditions of dams.
Analysis of Seismic Performance of the New Self-centering Buckling Restrained Brace
Authors: Qingxuan Shi , Yanchun Wang , Feng Wang
Published: August 2020

A new structure of self-centering buckling restrained brace was proposed. The finite element model was established by ABAQUS software. The mechanical failure mechanism of this kind of self-centering buckling restrained brace was studied. The influence of the parameters such as the area of self-centering reinforcement and the sectional area of core tube on its hysteretic performance and self-centering ability was analyzed. The results show that with the increase of the area of the reset reinforcement, the hysteretic curve of the brace is more pinched, and the self-centering ability is increased by 46%; it was suggested that the weakening degree of the cross-sectional area of the core tube should not exceed 50%.
Sensitivity analysis and instability study of mechanical parameters of deterioration layer of RCC dam
Authors: Liu Yongtao , Zhang Hailong , Zheng Dongjian , Cao Enhua , Kuai Pengcheng
Published: August 2020

Aiming at the characteristics of multi-layer structure of roller compacted concrete (RCC) dam and the complicated combination of layers, the three-dimensional calculation of the structure of RCC dam adopts the multi-layer elastoplastic constitutive model. The influence of various parameters of RCC dam deterioration on the strength of the dam body was analyzed in detail. The Latin hypercube algorithm was used to randomly sample each material parameter. The sensitivity of the degraded interlayer parameters was studied based on the Spearman rank correlation coefficient. To solve the simulation The non-stationary randomness of the degradation process, the introduction of the impact factor attenuation function to smooth the degradation, the establishment of a time-varying model of material parameter degradation, and on the basis of the strength reduction coefficient method, the degradation driving level of the RCC dam is calculated. Through the research results, it is possible to focus on monitoring the relevant aspects of the dam during operation, take relevant measures in real time, and feedback on the design and construction plan, which is of great significance for the research on the stability of the RCC dam against sliding.
Stability evaluation of soil sites based on fuzzy analytic hierarchy process
Authors: Ma Qingwen , Fan Xinyu , Liu Sihan
Published: August 2020

In order to accurately evaluate the stability of the present situation of the soil site, considering that the stability of the soil site is affected by its own structural characteristics and the external environment, the multiple factors affecting the stability of the soil site are determined, and the stability evaluation system of the soil site is constructed. The evaluation system is divided into three levels: target level, three primary levels and fifteen secondary levels, and four evaluation levels. Firstly, the weight value of the soil site stability evaluation index was determined by AHP, and the rationality of the evaluation index was verified by consistency test. Based on the expert experience and two kinds of ridge type membership functions, the fuzzy comprehensive evaluation model of soil site stability at three levels and two stages was established. Finally, combined with the analysis of engineering examples, it is shown that the fuzzy analytic hierarchy process is an effective method for the stability evaluation of soil sites, which can not only achieve the dual goals of safety, reliability and economic rationality, but also provide a basis for the selection of soil site disease control schemes.
Study on the long-lasting Anti-corrosion Construction Technology of Steel Structure of Service Tower in a Coastal Launching Site
Authors: Gu Yufei , Zhang Lijun , Chen Shaojiang , Feng Jiaoni , Xu Feiran
Published: August 2020

In order to realize the long-lasting corrosion protection of the steel structure of service tower in a coastal launch site under C5-M corrosion environment, a five-layer heavy anti-corrosion system with hot spray zinc aluminum alloy as the base, and the supporting process and control requirements are put forward. And this paper studied on the difficult problems encountered in the site construction process, such as the high requirements of pre-treatment of substrate surfaces, difficulty of the protection of finished products and difficulty of coating process control. The actual construction shows that the proposed measures are limited, the coating effect is good, and the research results can guide the anti-corrosion construction.
Novel concepts for establishing expert support systems to investigate the defect occurring in metallurgical phases in the technology of ISD DUNAFERR Zrt.
Authors: Wizner K , Kővári A
Published: August 2020

Competition among steel companies is intense in order to retain customers and get/gain new ones. Economic operators are much more critical of their suppliers and of the quality of their products due to increasing quality requirements. In addition to quality improvement measures to meet quality demands, cost optimization measures pose a major challenge for manufacturers.

Complaints always require an overview of the manufacturing process of the particular product, as it is essential for product development and can highlight technological issues that can eliminate similar types of complaints (improve product quality).

The investigation of the complaints requires extensive professional experience. Deep theoretical knowledge of the technological process, practical experience and knowledge of the local circumstances are essential. This amount of knowledge is available to the experts in varying degrees, and therefore, in addition to examining the main parameters, the aspects of the investigation may vary considerably. By creating or expanding a unified knowledge base, certain parts of the investigation can be analyzed and automated in higher detail. With this solution, the burden on experts is reduced, uniform investigation becomes possible, and examination aspects can be classified. Further statistical analysis may even make it possible to filter out technological parameters that are critical for quality.

The system described below is primarily designed from a metallurgical point of view, but with the expansion of its knowledge base it is also possible to study additional technological phases.
Investigation of the Melting Point Depression of Copper Nanoparticles
Authors: Somlyai-Sipos L , Janovszky D , Sycheva A , Baumli P
Published: August 2020

In this paper copper nanoparticles (Cu NPs) have been produced by solvothermal method. One of the objectives of the present research was to create Cu NPs using aqueous medium technology. The analysis of the produced particles was performed by X-ray diffraction (XRD) and Scanning Electron Microscopy (SEM). In the course of the experiments, copper core and organic shell nanoparticles were created successfully. It has been found that the average diameter of the created Cu NPs was 50 nm. The thermal behaviour of these particles was investigated by Differential Scanning Calorimetry (DSC). The melting temperature depression of the one-pot synthesized Cu NPs was 633 °C.
Mechanical property evaluation of closed and open-cell foam structures with finite element method
Authors: Kulcsár K , Kónya J , Zsoldos I
Published: August 2020

In this study, different lattice structures were examined with finite element method. Mechanical stress evaluations were performed on porous structured lattices that consisted simple cubic, face-centered cubic, body-centered cubic, and diamond unit cells. Finite element method simulations showed that structured foams with open and closed cells produced significantly different stress levels depending on their packing fraction. The aim of this study is to provide a basis for the design of an implant system that would promote the process of osseointegration.
Characterization of chemically foamed poly(lactic acid)
Authors: Litauszki K , Kmetty Á
Published: August 2020

This paper presents the characterization of poly(lactic acid)-based chemically foamed foam structures. We used extrusion grade, high molecular weight poly(lactic acid) as matrix material and azodicarbonamide as foaming agent. The resulting foams were characterized by foam density, cell population density, scanning electron microscopy, and based on the fracture surface of the foam cross-section, we calculated cell size distribution. The obtained distributions were fitted with the use of log-normal distribution in each case. We presented the effect of chemical blowing agent content (0.5 wt%, 1 wt%, 2 wt%, 4 wt% and 8 wt%) on the PLA-based foam structure and the effect of processing temperature (190 °C, 210 °C and 230 °C) on cell size distribution.
Simulation of hot rolling by cellular automata
Authors: Hegyes T , Barkóczy P
Published: August 2020

This development is focusing on one of the most complex and important production steps of flat rolled products that is the simulation of hot rolling. During hot rolling two phenomena, work hardening and the process of regeneration of microstructure have strong influence for physical properties of aluminium alloys. Dynamic recovery has importance in the dynamic softening beside dynamic recrystallization in aluminium alloys. Hot rolled and newly modified grain structure is influenced by these dynamic phenomena. Hot rolled grain structure goes through significant changes under further production steps like cold rolling and heat treatments. But aside from these intermediate production steps the microstructure that we get after hot rolling has significant effect on mechanical and grains structure of the final flat rolled product. Proper cellular automata simulations of recrystallization and recovery can be the basis for good technology planning practices.