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Innovation practice in engineering management of the Shenzhen International Low-Carbon City

Yimin LIU, Longbin HE, Xuan LI, Qin ZHENG

《工程管理前沿(英文)》 2019年 第6卷 第2期   页码 302-307 doi: 10.1007/s42524-019-0031-6

摘要: Shanghai Baoye Group Engineering Co., Ltd. Shenzhen Longgang Construction and Works Bureau Shenzhen Institute of Building Research Co., Ltd. Shenzhen Yinjian’an Engineering Project Management Co., Ltd. Shenzhen Jiuyi Green Operation Management Co. Ltd.

关键词: low-carbon city     low-carbon design     city-industry integration     low-carbon development     low-carbon management    

Simulation on thermodynamic state of ammonia carbonation at low temperature and low pressure

Jingcai ZHAO, Xingfu SONG, Ze SUN, Jianguo YU

《化学科学与工程前沿(英文)》 2013年 第7卷 第4期   页码 447-455 doi: 10.1007/s11705-013-1370-1

摘要: This study on thermodynamic property of NH -CO -H O system provided the basic data for ammonia carbonation. Simulations on vapor-liquid equilibrium (VLE) of ammonia carbonation with different physical properties were discussed in NH -H O and NH -CO -H O systems, respectively. The results indicated that at low temperature (303.15 K–363.15 K) and pressure (0.1–0.4 MPa), the PR (Peng-Robinson) equation was suitable for the description of the thermodynamic state in NH -H O system. NRTL (Non-Random-Two-Liquid) series models were selected for NH -CO -H O mixed electrolyte solution system. VLE data regression results showed that NRTL series models were suitable for describing thermodynamic properties of NH -CO -H O system, because average relative error fitting with each model was about 1%. As an asymmetric electrolytes model in NRTL model, E–NRTLRK (Electrolyte NRTL Redlich Kwong) could most accurately fit VLE data of NH -CO -H O system, with fitting error less than 1%. In the extent temperature range of 273.15 K–363.15 K, the prediction of product component using E-NRTLRK model for ammonia carbonation agreed well with the data reported in literature.

关键词: vapor-liquid equilibrium     activity coefficient     carbon dioxide     ammonia     NRTL    

Energy transition management towards a low-carbon world

《工程管理前沿(英文)》 2022年 第9卷 第3期   页码 499-503 doi: 10.1007/s42524-022-0201-9

关键词: energy transition     low-carbon technology     system modeling     transition path     emission reduction    

A hybrid method for product low-end disruptive innovation

《机械工程前沿(英文)》 2022年 第17卷 第3期 doi: 10.1007/s11465-022-0690-6

摘要: Product innovation is often a process for improving existing products. Low-end disruptive innovation (LDI) enables a product to meet the most price-sensitive customers in the low-end market. The existing LDI methods are mainly based on unnecessary characteristics of disruptive innovations. Thus, they cannot easily identify and respond to the LDI design needs. This study proposes a hybrid method for the product LDI in two levels of the product design based on the summarized definition and essential characteristics of LDI. Feasible areas of the product LDI are determined using a hybrid relational function model to identify the maturity of dominant technologies. The technologies are identified through the technical search and evaluation of the feasible area for innovation to form an initial LDI scheme. Then, the product function is optimized using the trimming concept of theory of inventive problem solving based on the characteristics of LDI. The final LDI scheme is formed and evaluated based on the essential characteristics of the product LDI. The feasibility of the proposed method is verified in the design of a new dropping pill machine.

关键词: low-end disruptive innovation     product design     design improvement     theory of inventive problem solving     TRIZ     trimming    

Acupuncture is ineffective for chronic low back pain? A critical analysis and rethinking

Xuqiang Wei, Baoyan Liu

《医学前沿(英文)》 2021年 第15卷 第5期   页码 767-775 doi: 10.1007/s11684-020-0785-6

摘要: Acupuncture is a promising treatment for relieving pain and improving lower back function in clinical practice. However, evidence from randomized clinical trials (RCTs) remains controversial. Most RCTs conclude that acupuncture procedures for chronic low back pain (CLBP) had no significant difference in efficacy and belonged to placebo. We carefully reviewed and analyzed the methodology and implementation of sham acupuncture in RCTs. Controversial evidence of acupuncture for CLBP is only a microcosm of the evaluation methodological limitation of acupuncture. Inappropriate selection of sham acupuncture controls, rigorous RCT research models, and incorrect interpretation of results may contribute to negative evidence. Evaluating and disregarding the holistic efficacy of acupuncture with an explanatory RCT model based on evaluation drugs may be unwise. Moreover, sham acupuncture is often proven to be non-inert, unreasonable, and with low fidelity. Pitfalls of the explanatory RCT model and sham acupuncture design should be avoided. Establishing a new evaluation system that is in line with the clinical characteristics of acupuncture and obtaining high-quality evidence are difficult but promising tasks.

关键词: chronic low back pain     sham acupuncture     acupuncture     methodology     therapeutic evaluation    

Research progress on low dielectric constant modification of cellulose insulating paper for power transformers

《化学科学与工程前沿(英文)》 2023年 第17卷 第8期   页码 991-1009 doi: 10.1007/s11705-022-2259-7

摘要: Because of the increase in the transmission voltage levels, the demand for insulation reliability of power transformers has increasingly become critical. Cellulose insulating paper is the main insulating component of power transformers. To improve the insulation level of ultrahigh voltage transformers and reduce their weight and size, reducing the dielectric constant of oil-immersed cellulose insulating paper is highly desired. Cellulose is used to produce power-transformer insulating papers owing to its excellent electrical properties, renewability, biodegradability and abundance. The dielectric constant of a cellulose insulating paper can be effectively reduced by chemical or physical modification. This study presents an overview of the foreign and domestic research status of the use of modification technology to reduce the dielectric constant of cellulose insulating papers. All the mentioned methods are analyzed in this study. Finally, some recommendations for future modified cellulose insulating paper research and applications are proposed. This paper can provide a reference for further research on low dielectric constant cellulose insulating paper in the future.

关键词: low dielectric constant     chemical and physical modification     cellulose insulating paper     transformer     nanomaterials.    

An improved low-complexity sum-product decoding algorithm for low-density parity-check codes

Michaelraj Kingston ROBERTS,Ramesh JAYABALAN

《信息与电子工程前沿(英文)》 2015年 第16卷 第6期   页码 511-518 doi: 10.1631/FITEE.1400269

摘要: In this paper, an improved low-complexity sum-product decoding algorithm is presented for low-density parity-check (LDPC) codes. In the proposed algorithm, reduction in computational complexity is achieved by utilizing fast Fourier transform (FFT) with time shift in the check node process. The improvement in the decoding performance is achieved by utilizing an optimized integer constant in the variable node process. Simulation results show that the proposed algorithm achieves an overall coding gain improvement ranging from 0.04 to 0.46 dB. Moreover, when compared with the sum-product algorithm (SPA), the proposed decoding algorithm can achieve a reduction of 42%-67% of the total number of arithmetic operations required for the decoding process.

关键词: Computational complexity     Coding gain     Fast Fourier transform (FFT)     Low-density parity-check (LDPC) codes     Sum-product algorithm (SPA)    

Research on low carbon management using a scientific classification method

Shanna QI, Meiting JU, Meng DUAN, Wei XING

《环境科学与工程前沿(英文)》 2012年 第6卷 第4期   页码 524-530 doi: 10.1007/s11783-011-0333-3

摘要: This research is aimed at the rapid development of a low-carbon economy, in which we propose the classification and application of relevant management measures to affect the development of environmental management ideas and measures of the low-carbon economy, which we called as low carbon management measures. According to scientific analysis of the low-carbon economy, we can divide low-carbon management measures into three parts: measures for reduction of carbon sources, carbon flow planning, and increase of carbon sinks. Furthermore, we list the advantages that China can utilize to develop its own low-carbon management measures. In the end, necessary adjustments to environmental management measures in China can be made according to this scientific classification.

关键词: low-carbon economy     low carbon management     carbon source     carbon flow     carbon sink    

Early-life famine exposure, adulthood obesity patterns, and risk of low-energy fracture

《医学前沿(英文)》 doi: 10.1007/s11684-023-1023-9

摘要: Malnutrition in early life increases the risk of osteoporosis, but the association of early-life undernutrition combined with adulthood obesity patterns with low-energy fracture remains unknown. This study included 5323 community-dwelling subjects aged ≥40 years from China. Early-life famine exposure was identified based on the participants’ birth dates. General obesity was assessed using the body mass index (BMI), and abdominal obesity was evaluated with the waist-to-hip ratio (WHR). Low-energy fracture was defined as fracture occurring after the age of 40 typically caused by falls from standing height or lower. Compared to the nonexposed group, the group with fetal, childhood, and adolescence famine exposure was associated with an increased risk of fracture in women with odds ratios (ORs) and 95% confidence intervals (CIs) of 3.55 (1.57–8.05), 3.90 (1.57–9.71), and 3.53 (1.05–11.88), respectively, but not in men. Significant interactions were observed between fetal famine exposure and general obesity with fracture among women (P for interaction = 0.0008). Furthermore, compared with the groups with normal BMI and WHR, the group of women who underwent fetal famine exposure and had both general and abdominal obesity had the highest risk of fracture (OR, 95% CI: 3.32, 1.17–9.40). These results indicate that early-life famine exposure interacts with adulthood general obesity and significantly increases the risk of low-energy fracture later in life in women.

关键词: famine     obesity     body mass index     waist-to-hip ratio     low-energy fracture    

Investigation on the performance and detoxification of modified low temperature coal tar pitch

Fengyan SUN, Yu LIU

《结构与土木工程前沿(英文)》 2017年 第11卷 第3期   页码 315-321 doi: 10.1007/s11709-017-0386-x

摘要: In this paper, studies on the modification on the low temperature coal tar pitch extracted from coal tar residue in Inner Mongolia are conducted. First, the low temperature coal tar pitch in liquid state is solidified with a higher softening point by chemical crosslinking modification. The modified coal tar pitch can achieve the standard pavement performance requirements. Then, the effects of chemical crosslinking agent and physical modification additives on the mechanical performance and toxic properties of coal tar pitch are investigated. The detoxification mechanism is also studied, which further promote the applicability of modified low temperature coal tar pitch in the pavement constructions.

关键词: coal tar pitch     low temperature     modification     detoxification    

A review on the development of electrolytes for lithium-based batteries for low temperature applications

《能源前沿(英文)》 2023年 第17卷 第1期   页码 43-71 doi: 10.1007/s11708-022-0853-5

摘要: The aerospace industry relies heavily on lithium-ion batteries in instrumentation such as satellites and land rovers. This equipment is exposed to extremely low temperatures in space or on the Martian surface. The extremely low temperatures affect the discharge characteristics of the battery and decrease its available working capacity. Various solvents, cosolvents, additives, and salts have been researched to fine tune the conductivity, solvation, and solid-electrolyte interface forming properties of the electrolytes. Several different resistive phenomena have been investigated to precisely determine the most limiting steps during charge and discharge at low temperatures. Longer mission lifespans as well as self-reliance on the chemistry are now highly desirable to allow low temperature performance rather than rely on external heating components. As Martian rovers are equipped with greater instrumentation and demands for greater energy storage rise, new materials also need to be adopted involving next generation lithium-ion chemistry to increase available capacity. With these objectives in mind, tailoring of the electrolyte with higher-capacity materials such as lithium metal and silicon anodes at low temperatures is of high priority. This review paper highlights the progression of electrolyte research for low temperature performance of lithium-ion batteries over the previous several decades.

关键词: electrolyte     lithium-ion     low temperature     aerospace     solid-electrolyte interface    

Case-based reasoning for selection of the best practices in low-carbon city development

Zhenhua HUANG, Hongqin FAN, Liyin SHEN

《工程管理前沿(英文)》 2019年 第6卷 第3期   页码 416-432 doi: 10.1007/s42524-019-0036-1

摘要: Cities emit extensive carbon emissions, which are considered a major contributor to the severe issue of climate change. Various low-carbon development programs have been initiated at the city level worldwide to address this problem. These practices are invaluable in promoting the development of low-carbon cities. Therefore, an effective approach should be developed to help decision makers select the best practices from previous experience on the basis of the impact features of carbon emission and city context features. This study introduces a case-based reasoning methodology for a specific city to select the best practices as references for low-carbon city development. The proposed methodology consists of three main components, namely, case representation, case retrieval, and case adaption and retention. For city representation, this study selects city context features and the impact features of carbon emission to characterize and represent a city. The proposed methodology is demonstrated by applying it to the selection of the best practices for low-carbon development of Chengdu City in Sichuan Province, China.

关键词: low-carbon city     carbon emission     best practices     case-based reasoning    

A review of low-temperature plasma-assisted machining: from mechanism to application

《机械工程前沿(英文)》 2023年 第18卷 第1期 doi: 10.1007/s11465-022-0734-y

摘要: Materials with high hardness, strength or plasticity have been widely used in the fields of aviation, aerospace, and military, among others. However, the poor machinability of these materials leads to large cutting forces, high cutting temperatures, serious tool wear, and chip adhesion, which affect machining quality. Low-temperature plasma contains a variety of active particles and can effectively adjust material properties, including hardness, strength, ductility, and wettability, significantly improving material machinability. In this paper, we first discuss the mechanisms and applications of low-temperature plasma-assisted machining. After introducing the characteristics, classifications, and action mechanisms of the low-temperature plasma, we describe the effects of the low-temperature plasma on different machining processes of various difficult-to-cut materials. The low-temperature plasma can be classified as hot plasma and cold plasma according to the different equilibrium states. Hot plasma improves material machinability via the thermal softening effect induced by the high temperature, whereas the main mechanisms of the cold plasma can be summarized as chemical reactions to reduce material hardness, the hydrophilization effect to improve surface wettability, and the Rehbinder effect to promote fracture. In addition, hybrid machining methods combining the merits of the low-temperature plasma and other energy fields like ultrasonic vibration, liquid nitrogen, and minimum quantity lubrication are also described and analyzed. Finally, the promising development trends of low-temperature plasma-assisted machining are presented, which include more precise control of the heat-affected zone in hot plasma-assisted machining, cold plasma-assisted polishing of metal materials, and further investigations on the reaction mechanisms between the cold plasma and other materials.

关键词: low-temperature plasma     difficult-to-cut material     machinability     hydrophilization effect     Rehbinder effect    

Remediation of soil heavily polluted with polychlorinated biphenyls using a low-temperature plasma technique

Xiuhua LI, Haibo ZHANG, Yongming LUO, Ying TENG

《环境科学与工程前沿(英文)》 2014年 第8卷 第2期   页码 277-283 doi: 10.1007/s11783-013-0562-8

摘要: Polychlorinated biphenyls PCBs) were removed by low-temperature plasma technique (dielectric barrier discharge) from heavily polluted soil and their intermediate products were analyzed. The removal rate ranged from 40.1 to 84.6% by different treatments, and they were also influenced significantly ( <0.01) by soil particle-size, electric power, gas flow rate and reaction time. The optimal reaction conditions of PCB removal from the soil were obtained experimentally when soil particle-size, electrical power, flow rate and reaction time were 5–10 mm, 21 w, 120 mL· min and 90 min, respectively. However, decreasing electrical power, flow rate and reaction time to 18 w, 60 mL· min and 60 min respectively were also acceptable in view of the cost of remediation. This technique was characterized by the additional advantage of thorough oxidation of PCBs in the soil, with no formation of intermediate products after reaction. The technique therefore shows some promise for application in the remediation of soils contaminated with persistent organic pollutants in brown field sites in urban areas.

关键词: polychlorinated biphenyls     low-temperature plasma     soil contamination     intermediate products    

The linkage mechanism between urban intelligence and low carbon innovation

Ming LIN

《工程管理前沿(英文)》 2019年 第6卷 第4期   页码 584-586 doi: 10.1007/s42524-019-0076-6

标题 作者 时间 类型 操作

Innovation practice in engineering management of the Shenzhen International Low-Carbon City

Yimin LIU, Longbin HE, Xuan LI, Qin ZHENG

期刊论文

Simulation on thermodynamic state of ammonia carbonation at low temperature and low pressure

Jingcai ZHAO, Xingfu SONG, Ze SUN, Jianguo YU

期刊论文

Energy transition management towards a low-carbon world

期刊论文

A hybrid method for product low-end disruptive innovation

期刊论文

Acupuncture is ineffective for chronic low back pain? A critical analysis and rethinking

Xuqiang Wei, Baoyan Liu

期刊论文

Research progress on low dielectric constant modification of cellulose insulating paper for power transformers

期刊论文

An improved low-complexity sum-product decoding algorithm for low-density parity-check codes

Michaelraj Kingston ROBERTS,Ramesh JAYABALAN

期刊论文

Research on low carbon management using a scientific classification method

Shanna QI, Meiting JU, Meng DUAN, Wei XING

期刊论文

Early-life famine exposure, adulthood obesity patterns, and risk of low-energy fracture

期刊论文

Investigation on the performance and detoxification of modified low temperature coal tar pitch

Fengyan SUN, Yu LIU

期刊论文

A review on the development of electrolytes for lithium-based batteries for low temperature applications

期刊论文

Case-based reasoning for selection of the best practices in low-carbon city development

Zhenhua HUANG, Hongqin FAN, Liyin SHEN

期刊论文

A review of low-temperature plasma-assisted machining: from mechanism to application

期刊论文

Remediation of soil heavily polluted with polychlorinated biphenyls using a low-temperature plasma technique

Xiuhua LI, Haibo ZHANG, Yongming LUO, Ying TENG

期刊论文

The linkage mechanism between urban intelligence and low carbon innovation

Ming LIN

期刊论文