bluuebunny/crossref_metadata_2025 huggingface dataset:
Mapping Flexibility of Urban Energy Systems (FIRST) project: Rationale and study design of an exploratory project
Authors: Aelenei D , Amaral Lopes R , Silva C , Aelenei L , Costa F , Majdalani N , Simões T , Martins J , Gonçalves H
Published: August 2019

With the publication of the new Energy Performance of Buildings Directive, a large number of buildings are expected to become high energy performance and explore more the availability of renewable energy resources. Such buildings are often described in literature as nearly Zero-Energy Buildings (nZEB). Because renewable energy sources, such as wind and solar power, have an intrinsic variability, the zero-energy annual balance of nZEBs is difficult to reach at short time resolution (e.g. hourly). Thus, since electricity generation from small-scale solar renewable (typical case in Portugal) in individual households has limited capacity to be adjusted according to the power system needs, it is relevant to consider the demand flexibility potential, specially at community level (cluster of buildings). Unfortunately, there is a lack of studies on the impact of changes in electricity use at urban level on the future energy systems. Therefore, an approach addressing the energy flexibility (EF) in buildings may allow obtaining useful exploratory directions for the construction sector and related markets, policy makers and regulatory bodies. For these reasons, an exploratory project aimed at examining the potential of EF at the level of an existent neighbourhood in Lisbon was initiated. In this article we describe the objectives, design, and methods of the FIRST project, designed to map out the potential for EF in terms of benefits and costs in Lisbon.
Virtual Singapore integration with energy simulation and canopy modelling for climate assessment
Authors: Ignatius M , Wong N H , Martin M , Chen S
Published: August 2019

Urban heat island (UHI) can be described as characteristics of warmth for both the atmospheres and surfaces in cities compared to rural surroundings. The attention on UHI has helped to advance the development of urban cooling strategies in Singapore. However, these strategies are often implemented at different levels with different mechanisms, and studies on the environmental implications of these strategies are often segregated. Therefore, understanding on how the urban canopy works is vital to analyse the energy performance, because canopy modelling is significant in estimating urban weather conditions, which affects the heat gain intake for buildings. It is thus become imperative to develop an integrated model for accurate prediction of weather conditions at different scales. By utilizing the Virtual Singapore (VSg) database, this study explores the development an integrated simulation platform, named BESCAM, for climate assessment and district energy demand. It focuses on urban canopy modelling and building energy simulation. The approach is to use CityGML from VSg as input, which comprises converted Building Information Modelling (BIM) buildings. Then, an urban canopy modelling (UCM) is developed to assess the microclimate condition with urban morphology consideration. Afterwards, building energy simulation can be conducted consecutively using EnergyPlus by integrating microclimate and building information. Hence, the BESCAM platform would offer a unique opportunity to architects, engineers, and scientists to use the same source of information, using VSg database, for conducting their own analysis and compare their conclusions.
Spatial quality of renovated open space in Tokyo via the experiences of users with urban gardening
Authors: Nguyen Tran Y K , Murata R
Published: August 2019

Since last century, megacities have been seeking measures to enhance the living condition of its urban dwellers by green infrastructures like parks or rooftop greening. Their social and environmental benefits offer considerable solutions for sustainable urban design, which is a critical concern in the era of climate change. Additionally, other concern of compacts cities is to improve the quality of their neglected open space and accommodate the city lifestyle. These concerns mentioned above lead to a noticeable trend of designing renovated open space (OS) using urban gardening (UG) in recent years, intending to raise awareness of natural resource in the urban area. In Japan particularly, research proves that gardening for leisure is improving the well-being of urban citizen, especially in Tokyo metropolitan. However, the past research focus was on the impact of UG on people, the management or the technic employed but not on the spatial quality itself, like the one in the author’s previous study. In the author’s recent work, open space with urban gardening (OSUG) was examined firstly through the user’s eyes to reveal their experience in space. Then seven scenarios were identified to determine the quality of urban space in OSUG, as characterized by the variation of three factors: Usage, Space Affordance, and Image of Identity. In this study, space itself will be analysed in connection with the design concept to understand the user’s experience linked to Space Affordance (SA). The finding will reveal the impact of SA in the relation of design concept and the user’s experience. Based on that a method for the future design of urban green space for compacts cities can be defined.
Estimation of time series urban energy demand and Examination of optimal energy supply system
Authors: Takahashi K , Ueno T , Sumiyoshi D
Published: August 2019

From the background of the liberalization of electricity and city gas retail market, it is considered that in the future Japan will move to a distributed supply form from each building and household. In order to properly place and operate this decentralized supply facility in the city, knowledge of time-series demand fluctuation in urban scale is necessary, but since there is no data or estimation method corresponding to this, it is necessary to develop one.

In this research, we first developed a program to estimate the energy demand fluctuation at five-minute intervals of non-residential buildings in urban scale into four energy applications (electricity, cooling, heating, and hot water supply). First, we acquire the building information (usage, extended floor, and coordinates) of the target city by GIS (Geographic Information System) data. Based on this data, we predict the demand fluctuation by building as a reference. By distributing the value, using probability density based on statistical and measurement data, we reproduced the variation of demand due to the difference of building characteristics which cannot be obtained via GIS data. We estimate the demand fluctuation for a city by integrating the building-specific demand fluctuation estimation values.

In this paper, the calculation was carried out using a program for Fukuoka city, Tenjin and Hakata districts, and the estimation result was compared and verified.

Based on the data obtained by the urban energy demand estimation program, we will consider optimal placement and operation methods of distributed supply equipment typified by PV panel, cogeneration, and storage battery. By flagging the presence or absence of equipment for each building and calculating it, we compared and examined the amount of energy reduction in each pattern.
A design-driven approach to integrate high-performance photovoltaics devices on the building façade
Authors: Chen T , Lau S Y , Zhang J , Xue X , Lau S K , Khoo Y S
Published: August 2019

To promote sustainable development, the Singapore government has set an aggressive target for PV deployment. However, as a highly urbanized city-state, Singapore has limited land space. Hence, innovative PV deployment is one area where Singapore is actively exploring. In urban environment, Singapore has a lot of vertical building surfaces; building-integrated PV (BIPV) is one of the good options to further increase PV adoption. Using a design-driven approach, this paper explores a different way of integrating PV modules on the building façade, considering the aesthetic as well as the building performance of PV modules.
Field Study of Passive Techniques and Adaptive Behaviour in the Traditional Courtyard Houses of Kabul
Authors: Fazeel Hosham Ayaz , Kubota Tetsu
Published: August 2019

This paper examined the passive techniques used in the traditional courtyard houses of Kabul using on-site measurements of their thermal environment during winter and summer. It was found that the high thermal mass structure was efficient in creating a stable indoor environment during both seasons. The adaptive behaviour of migrating horizontally to the northern and southern rooms during winter and summer was found to be effective. Moreover, the added insulation from the attached neighbour building and the thermal mass effect on the second layer rooms were found to play a major role in creating cool and stable indoor spaces in summer. The basements were among the coolest spaces during the summer months regardless of their opening conditions. However, a permanently closed basement was as cool as the minimum outdoor air temperature during the daytime. During the winter days, indoor thermal comfort varied based on solar orientation and the south facing rooms received direct solar radiation therefore provided longer comfort periods. The central courtyard was found to be a sheltered space during the winter and summer, which created a comfortable semi-outdoor space for specific periods during these months.
Development of a rating scale to measuring the KPIs in the generation and evaluation of holistic renovation scenarios
Authors: Kamari A , Kirkegaard PH
Published: August 2019

Future building renovation concerns sustainability in broader perspectives facilitated by holistic renovation scenarios. The aim of this paper is firstly identification of both objective and subjective used sustainability sub-criteria and their relevant most effective Key Performance Indicators (KPIs) in building renovation context. It is carried out by adopting a five-stage systematic methodology including review of Danish Standards for the renovation of dwellings. This is a focal point for most – if not all – design team and consultancies interested in renovation projects. Whilst the answer to this is of course very contextual, this paper presents an overview of the sustainability criteria beside their relevant KPIs and how they are perceived and measured by the professional practitioners. To do so, the efforts are put in place towards the development of a rating scale to measuring the sustainability-related measurable KPIs in the generation and evaluation of holistic renovation scenarios for dwellings.
A simulation based framework to optimize the interior design parameters for effective Indoor Environmental Quality (IEQ) experience in affordable residential units: Cases from Mumbai, India
Authors: Sarkar A , Bardhan R
Published: August 2019

This study intends to optimise the interior layout of two low-income multi-rise tenement designs that would provide effective indoor environmental quality (IEQ) over the breathing zone. A variety of interior layouts were generated for both space constrained tenement units by introducing and varying interior architectural parameters and their respective design variables such as partition wall, cook-stove and furniture location. The study initiated with in-situ sensor development coupled with a stepwise simulation based framework involving sampling based parametric modelling followed by CFD simulations and multi-objective optimisation. Air velocity, temperature, and pollutant concentrations were considered as surrogate measures of IEQ. The research finally delivered two varying interior design layout with optimised design variables that would deliver indoor air quality within comfort range over the breathing zone in nat-vent conditions. Dearth of sustainable design strategies is a major dead-spot in habitat planning policies of India and needs urgent attention. This data driven research heuristics if applied through building design guidelines would help the architects, building engineers and urban planners to design and rejuvenate slum and low-income habitats by imbibing the environmental sustainability aspect in habit design policies.
A New Through-Wall Air Conditioning System with Improved Performance for High-Rise Office Buildings
Authors: Tsukami Shiro , Kubo Hirotaka , Icinose Masayuki , Kato Takaya
Published: August 2019

As one type of perimeter air conditioning (AC) systems, there is a through-wall unit (TWU) that processes perimeter heat by exchanging heat with an outdoor fan from an exterior grill on the outer wall of a building. In this study, we improved the TWU by adding a new operation mode to cascade-use room exhaust air for the compressor heat exchange and developed a high efficiency perimeter air-conditioning system. This paper shows the outline of the new air-conditioning system by combining various operation patterns of the TWU. This enables selection corresponding to various air-conditioning needs in an office building, and it improves comfort and saves energy. In addition, the TWU exhaust performance tests of a sash shape model and a full scale model were carried out. From the viewpoint of exhaust performance when using a TWU in a high-rise building, and achieving the necessary cooling and heating capacity, it was confirmed that this would perform well.
Impact of occupants’ behaviour on energy consumption and corresponding strategies in office buildings
Authors: Dong Zhao , Zhao Kang , Hua Ying , Xue Yucong , Ge Jian
Published: August 2019

Among commercial buildings, office buildings have the largest number and have the highest total energy consumption (about 14% of the energy consumed by all commercial buildings). Energy used by the HVAC and lighting systems to create comfort indoor thermal and visual environments account for more than half of the total energy usage. The utilization rate of space affects the actual requirement of space heating, cooling and lighting, as well as the performance of equipment and systems. A slow but steady increase in office vacancy is observed as more people work asymmetrically across increasingly remote locations or with a more flexible schedule. Unlike in traditional offices, work style in many new offices involves towards a shared workplace with diverse work activities. This paper focuses on the impact of occupants’ behaviour on energy utilization in different types of office buildings and corresponding workplace spatial strategies. The features of the energy use for space cooling, heating and lighting with different occupant rates in different spatial settings, such as private office, open office and coworking office, are depicted. Furthermore, the potential for energy savings with optimization technique, i.e., integrating the real time occupancy data into building air-conditioning and lighting systems for usage-based demand control strategies, are estimated with the method of simulation. According to the calculation results, strategies for improving energy consumption for different office settings are proposed respectively for design and operation.
Comparative Study on Energy Consumption in the Asian Landlocked Countries
Authors: Fukuyo K , Hirohata N
Published: August 2019

This paper focuses on the present and future of the residential energy consumption in the Asian landlocked countries: Laos (Lao PDR) and Nepal. Although Laos and Nepal are classified as the least developed countries (LDCs) and share many similarities in terms of geographical and socio-economic features, energy use, especially electricity use, is very different. In 2016, the residential electricity consumption (per capita per annum) of Laos and Nepal are 256.8kWh and 79.5kWh, respectively. The regression analysis and the Granger causality test show that there is quantitative and causal relationship between the economic growth and residential electricity consumption. The difference in the electricity consumption is thus able to be illustrated by their economic disparity. And moreover, if the linear relationship between the per capita GDP and residential electricity consumption continues in Nepal for many years to come, Nepal can catch up with Laos in terms of residential electricity use when the level of economic development reaches to that of Laos. However, a detailed consideration draws attention to the fact that Nepal is way behind in the electricity generation capacity per capita as compared with Laos. The limitation of installed capacity may suppress the growth of ownership of home appliances and the residential electricity use in Nepal in the near future despite of the high access to electricity and their abundant water resources.
Optimization of process parameters for pipeline CO2 transportation with impurities
Authors: Chen Bing , Guo Huanhuan , Bai Shixing , Cao Shuangge
Published: August 2019

According to the actual engineering experience of many years of abroad, and impurities will have an impact on pipeline transportation parameters. This paper takes the 300,000 tons/year CCUS project of an oilfield in China as an example. The Pipe phase simulation software was used to simulate the supercritical dense phase carbon dioxide pipelines with different inlet diameters under the same inlet parameters, and analyze the most suitable pipeline transportation process parameters for impurities containing supercritical dense phase carbon dioxide. The feasibility plan of carbon dioxide pipeline transportation has laid a foundation for the comprehensive construction of carbon dioxide pipeline network in China.
Design and Exploration of Drainage System based on Pressure Pipeline in Buildings
Authors: Jiang Xiaoxin , Wu Bi
Published: August 2019

In order to improve the drainage system of buildings in China, the drainage system based on pressure pipeline is studied. Firstly, the development background of building drainage in China is described, and the flow algorithm of pressure pipeline is introduced. On this basis, the drainage test of single riser and double riser system is designed. Through comparative analysis of the test, the drainage characteristics of the pipeline drainage system are obtained, and the relevant design methods of the drainage system in buildings are obtained based on the pressure pipeline. The drainage performance of double risers is better than that of single risers. Double risers should be used as much as possible in construction, especially in high-rise buildings. Drainage of high-rise buildings is complex, and large changes in water pressure are easily formed in pipeline, which may damage indoor water-using equipment, make odorous gases in pipelines enter indoors, and destroy living environment. The research results can provide data reference for building drainage design, provide parameter basis for testing standards of drainage capacity of residential drainage system, and improve building drainage system in China.
Study on durability of ultra high performances concrete with aeolian sand
Authors: Wang Jurui , Ou Zhongwen , Liu Jinming , Xiong Zhiqing , Wang Jingwei , Wang Yueyang , Luo Wei , Liu Yang
Published: August 2019

Compared with ordinary concrete and high strength concrete, ultra-high performance concrete has more excellent mechanical properties and durability. It has great social and economic benefits to prepare ultra-high performance aeolian sand concrete using aeolian sand as aggregate. It is of great significance to study the durability of ultra-high performance aeolian sand concrete. The mechanical properties and durability of ultra-high performance concrete are analyzed and compared by optimizing mix ratio and optimizing mix ratio. The test results show that the compressive strength of ultra-high performance aeolian sand concrete loses obviously after 300 freeze-thaw cycles. However, the splitting tensile strength is not affected by the number of freeze-thaw cycles; the strength of ultra-high performance aeolian sand concrete is not affected by sulfate immersion; with the increase of the number of drywet cycle-sulfate erosion coupling cycles, the compressive strength and splitting tensile strength of ultra-high performance aeolian sand concrete decrease rapidly at first, then increase gradually, and then decrease rapidly.
Regional terrain complexity evaluation based on GIS and K-means clustering model: a case study of Ningdu County, China
Authors: Kang Wenjing , Huang Faming , Du Yaoxian , Liu Dalin , Cao Zhongshan
Published: August 2019

In order to accurately quantify the terrain complexity, a simple and accurate terrain complexity assessment (TCA) model is proposed. Taking Ningdu county in Jiangxi Province of China as an example, firstly, six terrain factors (named slope, topographic relief degree, surface cutting depth, surface roughness, elevation variation coefficient and topographic factors) of Ningdu county are extracted based on the Digital Elevation Model (DEM) with 30 m resolution and ARCGIS 10.2 software. Secondly, terrain complexity indexes of Ningdu County are obtained using k-means clustering. Results show that a current and effective spatial distribution characteristic of topographic complexity in Ningdu county is produced, and the very low and low terrain complexity indexes account for 33.28%, 28.35% respectively. The terrain complexity can be evaluated effectively by k-means clustering model. The terrain complexity can be provided for environmental protection and land use planning.
Dynamic mechanism of non-ferrous metal processing industry transfer in Qinghai province based on production function
Authors: Zou Di , Ma Shichang
Published: August 2019

Non-ferrous processing industry is related to all aspects of residents’ life and has a prominent industrial position in Qinghai Province. The driving force of industry transfer is closely related to the production function of enterprises. The OP method established by Olley and Pakes, the LP method established by Levinsohn and Petrin have guiding significance for the estimation of the production function of enterprises. In this paper, OP method and LP method are used to estimate the production function of the non-ferrous metal processing industry in Qinghai province based on the statistical data of industrial economy over the years, calculate the total factor productivity of the industry, and summarize the transfer power mechanism of the non-ferrous metal processing industry in Qinghai province.
Experimental analysis and parameter optimization of pdc bit for rock drilling trolley
Authors: Zhang Jinchun , Li Qing , Yi Wencui
Published: August 2019

The design parameters of PDC bits for rock drilling trolley have not been studied in depth and it is lack of theoretical research basis. So the service life of the bits for tunnel tunneling construction cannot meet the design and application requirements. Taking three-arm rock drilling trolley as the experimental platform, the key parameters of PDC bit crown profile shape, caster angle, cutting tooth size, tooth arrangement density, inner cone angle, outer swing angle and crown top shape for rock drilling trolley are designed by combining the optimum design method, empirical numerical value and experimental correction. The key parameters were optimized and improved through a set of manufactured bits, and a set of drills were manufactured again for the following experiment. The experimental data in second stage shows that the broken and drop defects of the improved bits are greatly reduced. The drilling depth is significantly increased, and the service life is also improved, which meets the requirements of design and operation.
Dynamic response study of buried pipe subjected to dynamic compaction
Authors: Du Jifang , Wu Shuaifeng , Zhang Yinqiu , Hou Sen
Published: August 2019

Monitoring the internal vibration of the soil under dynamic compaction is often influenced by the environment. If the sensor is located in the crushed rock soil, its monitoring data often do not have typical representativeness. Therefore, a monitoring method of sensors placed in pipe is proposed. Based on the experience of earthquake and blasting engineering, the feasibility of the measurement method is studied and the results showed that the sensors placed in PVC pipes can reflect the response of soil. Two field tests, low energy and high energy, were conducted to verify the conclusion. After comparison of various vibration characteristics including waveform, Fourier spectrum, and amplitude attenuations with distance, the velocity of the sensors in PVC pipe showed linear relationship with sensors in soil. It can be concluded that the sensors placed in PVC pipe can be used for the test of vibration in soil and represent the typical vibration of the whole stratum.
Evaluation model of two-stage gravel packing sand control well based on additional pressure drop
Authors: Qi Minhui , Li Mingzhong , Li Tong , Liang Jun , Liu Chunting , Ma Junjie
Published: August 2019

Two-stage gravel pack sand control technology solves the problem of silt sand blockage in traditional high-pressure gravel pack, effectively improves the effective period and flow conductivity of the gravel pack. This technique has been widely used in the development of unconsolidated sandstone reservoirs, but the related studies still remain insufficient. In this paper, a sand control evaluation model based on additional pressure of the gravel packed layer is proposed for two-stage gravel packing sand control wells. Firstly, the complex mechanisms of sand plugging in gravel pack is divided into two types, horizontal and vertical, and the calculation model of dynamic permeability of the gravel pack is established. The finite element model of two-stage gravel packing sand control wells based on fluid-solid coupling is established by multi-physical coupling software COMSOL. The additional pressure drop of the sand control wells under various construction parameters is evaluated. Applying this method to evaluate a two-stage gravel packing well in Shengli Oilfield, it is concluded that after 200 days of production, the gravel pack’s additional pressure drop of the traditional packing increases to 2.5 MPa, while the overall additional pressure difference of two-stage gravel packing is stable at about 1.3 MPa. It is proved that two-stage gravel packing sand control technology can effectively reduce the additional pressure drop and improve the productivity of oil well after completion.
Study on feeding system performance of CBM carrier mounted rig
Authors: Chang Jianghua , Zhang Yang , Fan Dong , Tian Hongliang
Published: August 2019

Feeding system is the main mechanism of carrier mounted rig, and determines the rig’s performance. The feeding system contains stretching mast, which pulls the drive head through two hydraulic cylinders and steel cables, as a result, the rig has a compact structure and long feeding distance. The feeding system’s hydraulic system including two pumps and two control circuits is designed to meet the demand of fast round trip and pressure’s accurate control of drilling based on the analysis of drilling procedure and load performance. The two explosionproof valves on the head end of feeding cylinders guarantee the stable suspend and avoid percussion drilling after pipelines bursting and drilling tools dropping on account of maloperation. Furthermore, the two explosionproof valves make the pressure of the two head ends of feeding cylinders equal to ensure the two feeding cylinders to run in step through control ports in parallel. In the end, ZMK5530TZJ100 is developed and applied to construct a “L” horizontal directional well with a depth of 1675 m to verify the rationality and reliability of the rig’s feeding system.
Study on Wiped Area Measurement Method Based on 3D Scanning
Authors: Liang Haojie , Jiao Zhiwei
Published: August 2019

The coverage rate of wiped area is a critical index for designing the windshield wiper system and driver forward field of view in particular. SAE Recommended Practice clearly define the minimum requirements for wiped area that must be met before a passenger car can be sold. The challenge is to develop measurement methods which transfer wiper pattern extracted from the windshield glazing surface to the data that can be calculated. In this paper, we apply hand-held laser scanners to produce the point clouds of wiper pattern, convert them into computer-aided design model, and then trim areas A, B, and C according to the edge feature of wiper pattern, finally calculate the percentages of areas A, B, and C that are wiped. Compared with traditional photography-based measurement method, the application result showed that scanning-based method possess better accuracy performance for wiped area test.
Research on Main Geological Controls and Enrichment Model of Coalbed Methane Distribution in China
Authors: Wang Kexin
Published: August 2019

The distribution and enrichment of coalbed methane in China are controlled by various geological factors. A systematic study has been carried out on six aspects: geological structure conditions, burial depth, hydrogeological conditions, sedimentary environment, physical properties and magmatic activities of coalbed methane. The results show that tectonic subsidence, hydraulic sealing and gas control, reverse faults and synclinal core are controlled by structural subsidence, hydraulic sealing and gas control. It is advantageous to CBM occurrence; tectonic uplifting, hydraulic migration and dissipation, normal faults, anticlinal core and subsidence pillars are disadvantageous to CBM occurrence; with the increase of coal seam burial depth, the adsorption capacity of CBM increases gradually, and decreases after the critical burial depth; the thicker the thickness of coal seam roof and floor, the more dense of the lithology, the more favorable to CBM preservation; the content of CBM is positively correlated with coal thickness. According to the influence degree of geological factors, the distribution and occurrence of coalbed methane can be summarized as two types: comprehensive control of multiple factors and main control of one or two factors.
The dividing and value technique on well logs for Lithology identification of pyroclastic rocks
Authors: Dai Linlin , Lin Lili
Published: August 2019

The ability of logging curves to reflect the rock interface is related to logging principles, which is often different from the layer interface determined by coring. According to basic principle of logging curve, analyze the corresponding relationship between comprehensive lithologic boundary determined by coring and the boundary determined by well logging curve. The identification method combining the two technique is given. In view of that the logging curves are insensitive to some thin layers and transition lithology, the reasonable value method are given as a result. Using this result can well judge the change trend of lithologic profile.
Comparison and Research of Fisheye Image Correction Algorithms in Coal Mine Survey
Authors: Xu Mengxue
Published: August 2019

Fisheye lenses are widely used in scene surveillance, robot navigation and engineering measurement due to their wide field of view and short focal length. However, the image taken by the fisheye lens has a large degree of distortion, so image correction is the key point of research. In this paper based on the distortion of fisheye image in coal mine underground video surveillance system, the latitude and longitude coordinate method, spherical perspective projection method and panoramic stitching method commonly used in fisheye correction are compared and given an improved algorithm. In the actual survey image correction, preprocessing is an important process, that is, to find the center and radius of the fisheye image. The advantages and disadvantages of the algorithm for finding a circle are also compared.
Mechanical model of safety thickness for resource recovery of complex & difficult mining ore body
Authors: Xie Chengyu , Lu Hao , Chao Lei , Feng Renwu , Shi Dongping , Zhang Xiaoqiang , Tao Zhijie , Liu Guojun , Wang Xinfeng
Published: August 2019

In view of the difficulty in calculating the safe thickness of complex and difficult-to-mine orebody in the process of resource recovery, based on the elastic-plastic theory and mechanics method, the mechanical models of the safe thickness of orebody recovery above the collapse area and that of orebody recovery at the side of the collapse area are constructed respectively. The results show that: 1. Using the fixed beam model to calculate the safety thickness, the additional load on the roof, the volume weight and span of the rock stratum, the width of the rock stratum and the water pressure are the important influencing factors. When the water pressure exists, the safety thickness can be reduced; 2. When the safety thickness is calculated by the elastic plate model with fixed support around, the safety thickness decreases with the increase of the tensile strength or shear strength of rock mass, and increases with the increase of the external load; 3. When the collapse area is located at the side of the ore body to be mined, the safety thickness decreases with the increase of the tensile or shear strength of rock mass, and with the increase of the external force. The load increases with the increase of load. The research can provide theoretical support for mining residual mineral resources.
Analysis on Geological Conditions of Chang 7 Shale Gas Accumulation in Longdong Area in Ordos Basin
Authors: Li Zhenhua , Gai Ke , Yu Lan , Zhang Suya , Sun Ning , Li Xiangyang
Published: August 2019

The geological conditions of Chang 7 shale gas accumulation in Longdong area are analyzed from sedimentology, petrology and organic geochemical characteristics in this paper. The study shows that Chang 7 shale in Longdong area is mainly deposited in deep lake and semi deep lake, with thickness ranging from 10 m to 40 m. The shale is mainly composed of quartz, feldspar, clay minerals and a small amount of carbonate and pyrite, and its brittleness is high. TOC ranges from 1.5% to 20.0%, with an average of 7.9%, and hydrocarbon generation potential (S1+S2) ranges from 0.67 mg/g to 33.53 mg/g, with an average of 15.81 mg/g. The main organic matter belongs to type I and II, Ro ranges from 0.7% to 1.2%. It can be concluded that Chang 7 shale in Longdong area possesses favourable conditions for shale gas accumulation.
Comprehensive lithology identification of the Qingcheng formation in LS1 well area
Authors: Fan Yuanxun , Li Hongyu
Published: August 2019

Igneous reservoir, as a deep dominant reservoir, will mostly get high production once developed, but this kind of reservoir has long been the key and difficult point of well logging evaluation due to its complex lithology, various reservoir forming control factors and strong heterogeneity. Lithology identification is the primary task of well logging evaluation of igneous reservoir. Guided by the idea of sequential separation, this paper adopts conventional logging crossplot method and TAS chart method to identify the lithology of igneous rocks successively, meanwhile, the characteristics of igneous rocks imaging logging are summarized. Through the above research, a set of systematic lithology identification criteria for Yingcheng formation igneous rocks has been established.
Consolidation and Pore Pressure Characteristics of Remolded Unsaturated Loess Under Isotropic Stress
Authors: Jia Yajun , Chen Cunli , Zhang Dengfei
Published: August 2019

Loess is a typical unsaturated soil. The unsaturated constitutive model of loess is an important research direction of loess engineering characteristics. In this paper, the constant load K0 consolidation tests of unsaturated undisturbed loess with different water content are carried out, and the effects of water content on secant modulus, stress-strain characteristics and lateral pressure coefficient are analyzed.
Changes in The High-Latitude Headwater Basin of The Nenjiang River Basin, Northeast China, 1970s-2000s
Authors: Dong Liqin , Gong Hede , Wu Lihua
Published: August 2019

The Nenjiang River Basin (NRB), an important wetland area in China, has experienced large-scale degradation of the wetland area and the evolution of land-use patterns over the last 50 years due to global warming, changes in precipitation patterns and anthropogenic activities, especially in the headwater basin of the NRB. In order to investigate these changes, temperature, precipitation, runoff, land-use/vegetation and wetland changes from 1970s-2000s were analyzed using the Mann-Kendall non-parametric test and Arcgis10.2 software. Our results show that a temperature increase was recorded in the headwater basin of the NRB, and precipitation showed an overall increasing trend which became more evident in the headwater basin. Runoff presented an increasing trend on the right side of the basin and a decreasing trend on the right side. The occupation of agricultural land on the wetland area and a decrease of forest and grassland areas did not result in a significant reduction in floodplain wetland area. These land-use changes, however, did have an impact on water supply shortages in the agricultural zone to the left side of the NRB.
Experimental Study on The Effect of Charge Structure of Blasting on Damage to Dirt Band in Thin Coal Seam
Authors: Pan Yangbo , Zheng Mingliang , Xing Zhenqiang
Published: August 2019

Based on the coalmines with thin coal seam containing hard dirt band in Shandong Province, aiming at the problem of difficult mining caused by hard dirt band in the process of thin coal seam mining, the damage to hard dirt band by blasting in different charge structures was studied. According to the propagation law of blasting stress wave in coal and dirt band in different charge structures, an experimental platform was set up, and the damage characteristics of dirt band by blasting stress wave under the action of ordinary charge blasting and shaped charge blasting were studied through similar simulated comparative tests. The results show that in the ordinary blasting, the cracks spread out disorderly along the radial direction of the blasting hole and the damage of the dirt band is not so good; however, in shaped charge blasting, the peak stress increases 1.32 times in the direction of energy accumulation, while decreases 22% in the direction of non-energy accumulation, making the explosive energy more concentrated in the dirt band and forming a long and wide directional main crack in the dirt band.
Vertical Pullout Behaviour of a Torpedo Anchor Vertically in Stiff-Over-Soft Cohesive Soil Bed
Authors: Wang Cheng , Zhang Minxi , Yu Guoliang
Published: August 2019

This paper reports the results from a large deformation finite element (LDFE) model to provide insights into the vertical pullout behaviors of torpedo anchors in stiff-over-soft soil beds. 10 sets of numerical data were obtained by varying the top layer thickness, soil shear strength of the stiff-over-soft soil bed, tip embedment depth ratio, and pullout speed. The tip embedment depth ratio of the torpedo anchor (the ratio of the embedment depth at anchor tip to the anchor shaft length) varied from 1.48 to 2.91. Soil flow characteristic was discovered by the finite element analysis. The observation of soil flow characteristics provided deep insight with the interaction between the torpedo anchor and its surrounding soil.
Study on The Genesis of The Chedu Gold Deposit in Bikou Block
Authors: Wang Dequan , Wang Jianguo , Deng Shengbo , Wang Yizhong
Published: August 2019

The Chedu gold deposite is located in the south rim of bikou terrane. It is the first BIF-type gold deposit in shaanxi province. Experiment with electronic probes and scanning electron microscopy, we first discovered silver gold mine and calaverite wrapped in single-grain magnetite.According to the results of hydrogen and oxygen isotope analysis of quartz in gold ore, the value of δ18O is from 16.4 ‰ to 16.6 ‰ and δD is from 16.4 ‰ to 16.6 ‰. This value is similar to the hydrogen and oxygen isotope values of quartz in BIF type iron ore. The discovery of wrapped gold and non-visible gold in magnetite suggests that gold is formed earlier or at the same time as the magnetite crystallizes. It is of great significance to study the genesis mechanism of BIF type gold deposit.
Research on repeated loading and sinkage characteristics of soil by numerical analysis
Authors: He Jian , Wu DaLin , Ma JisSheng , Wang Hongkai
Published: August 2019

The research on repeated loading and sinkage characteristics of soil can calculate the sinkage of wheel and track in driving process more precisely, so it can help calculate the vibration characteristics and driving resistance of vehicle more accurately. This paper analysis the soil repeated loading and sinkage characteristics based on finite element method. The results shows that the unloading and reloading process of soil can be assumed as a straight line with slope of k on load-sinkage curve, here k is called rebound coefficient. The research conclusion can provide reference to the vehicle terramachanics and other research involved soil deformation.
Sedimentary Succession and Model of Gravel Beach-Bars in The Southeastern Qinghai Lake
Authors: Peng Biao , Ye Shenglan
Published: August 2019

The modern is the key to the past. Based on the field investigation of the Qinghai Lake, the authors have carried out the elaborate dissection of profiles parallelly and vertically with the shoreline and the surface analysis of the forming beach-bars. The sedimentary successions of gravel beach-bars are summarized and the model of gravel beach-bars are established. The gravel beach-bars have a fixed sedimentary succession, the “ABC” sequence. A interval, the bottom of the sedimentary succession, is composed of coarse sands and gravels, which are sub-rounded, poorly-sorted, massive, and gravels oriented floating in the coarse sands; B interval, the middle of the sedimentary succession, is composed of gravels, which are sub-round, well-sorted, and massive bedding; C interval, the top of the sedimentary succession, is composed of coarse sands, which are well-sorted and normally graded bedding. In the actual gravel beach-bars, three intervals are often presented in a variety of combinations, such as “ABCABC”, “BCBCBC”, “ABABAB” and other combinations. The hydrodynamic conditions of gravel beach-bars can be divided into three zone, wave asymmetric zone, breaker zone and surfing zone. The three zones respectively correspond with the A interval, B interval, and C interval. These findings provide an important basis for the reconstruction of paleoenvironment and the identification and distribution prediction of beach-bars in the ancient continental lake basins.
Study on the Viscosities of MDEA-Amino Acid Ionic Liquid Aqueous Solutions
Authors: Li Mengying , Lu Chunjie , Zhang Pan
Published: August 2019

The viscosities of 1-butyl-3-methylimidazolium glycine ([Bmim][Gly])-N-methyldiethanolamine (MDEA), tetramethyl amine glycine ([N1111] [Gly])-MDEA and l-butyl-3-methyl-imidazolium lysine ([Bmim][Lys])-MDEA aqueous solutions were respectively measured by using the NDJ-5S digital rotational viscometer. The temperatures ranged from 303.2K to 323.2K. The mass fractions of MDEA and amino acid ionic liquids (AAILs) respectively ranged from 0.30 to 0.45 and 0.05 to 0.15. The Weiland equation was used to correlate and predict the viscosities of [Bmim][Gly]-MDEA, [N1111] [Gly]-MDEA and [Bmim][Lys]-MDEA aqueous solutions. The temperature and mass fraction dependences of the viscosity of MDEA-AAIL aqueous solutions were demonstrated on the basis of experiments and calculations.
Application of combined remediation in heavy metal polluted soil
Authors: Xu Yan , Lu Yangjie , Tian Chang , Yang Jianqiang
Published: August 2019

Whether it is single or compound heavy metal pollution, it is universal, complex, and invisible. The soil pollution cannot be completely resolved only relying on a single repair technology, requiring multiple approaches often. The combined remediation technologies of soil pollution can exert respective advantages, abandon their shortcomings, and optimize the repair effect. Based on a large number of literature surveys, this article discussed the application of combined remediation in heavy metal-contaminated soils, in order to provide reference for the rehabilitation of heavy metal-contaminated soils.
The preparation of a straw engineering sand-fixing plank and its sand-fixing and replanting performance exploration
Authors: Pu Hongqin , Gao Dekuan , Wang Haiwang , Wu Zhengjie , Li Yuanming , Wang Guanqi , Zhang Yukai , Ma Yuan , Wang Bingzhu , Qi Xiwei
Published: August 2019

To improve the shortcoming of sand fixation in traditional engineering, the study prepares a kind of porous composite for sand fixation and replanting by taking waste straw as the skeleton, polyvinyl alcohol and aquasorb as the composite agent, then pressing moulding by a press machine. Firstly, the effect of PVA on the mechanical properties is studied by sheering strength. In addition, the fracture mechanism of the composite is analysed by infrared spectrum of the PVA and photos under the optical microscope. Then, it is studied the influence of the amount of aquasorb on the water absorption and retention ability of the composite through the water absorption ratio and water content. Besides, the good water retention and replanting performance of aquasorb is visualized through the macro humidity contrast. The results show that, with the increase of PVA content, its sheering strength first decreases and then increases to the peak value, which is as high as 4.79MPa. It can be seen through the analysis of fracture morphology, that the composite crosslinking of PVA and aquasorb forms a three-dimensional network structure. And the structure enhances the toughness of the composite. With the increase of the content of the aquasorb, the water absorption ratio and the water content first increase and then decrease. When the content is 33.33%, the effect reaches to the optimal level, the water absorption ratio reaches to 3.76 and the repeated water absorption ratio reaches to 2.71. What’s more, the water content is always higher than other proportions. Therefore, the composite can effectively cooperate with plants and extend the years of sand control. The study provides a new idea and basis for the combination of sand fixation and waste straw.
Life cycle assessment on metal supply from environmental perspective
Authors: Liu Yongquan , Diao Shujuan , Chang Yan
Published: August 2019

Metal supply is very important for economic development and the environmental effect on metal supply has become a serious problem. The main challenge is to decide how to quantify the environmental effect. A series of researches have promoted different methods. This paper promotes an improved approach for assessment of environmental effect on metal supply. LCA method was used and system steps of the mining and processing during LCA method of a specific metal was first identified. The midpoint and endpoint data were derived separately for Al and Cu as case study. Then normalization was applied to the endpoint data and the section with biggest value was considered most serious environmental effect. And the endpoint value for this section is chosen as environmental implication for a specific metal. We hope this approach can be a convenient and practical method for the environmental effect assessment.