Effects of cotton field management practices on soil CO2 emission and C balance in an arid region of Northwest China

Changes in both soil organic C storage and soil respiration in farmland ecosystems may affect atmospheric CO2 concentration and global C cycle. The objective of this field experiment was to study the effects of three crop field management practices on soil CO2 emission and C balance in a cotton field in an arid region of Northwest China. The three management practices were irrigation methods（drip and flood）, stubble managements（stubble-incorporated and stubble-removed） and fertilizer amendments（no fertilizer（CK）, chicken manure（OM）, inorganic N, P and K fertilizer（NPK）, and inorganic fertilizer plus chicken manure（NPK＋OM））. The results showed that within the C pool range, soil CO2 emission during the whole growing season was higher in the drip irrigation treatment than in the corresponding flood irrigation treatment, while soil organic C concentration was larger in the flood irrigation treatment than in the corresponding drip irrigation treatment. Furthermore, soil CO2 emission and organic C concentration were all higher in the stubble-incorporated treatment than in the corresponding stubble-removed treatment, and larger in the NPK＋OM treatment than in the other three fertilizer amendments within the C pool range. The combination of flood irrigation, stubble incorporation and application of either NPK＋OM or OM increased soil organic C concentration in the 0-60 cm soil depth. Calculation of net ecosystem productivity（NEP） under different management practices indicated that the combination of drip irrigation, stubble incorporation and NPK＋OM increased the size of the C pool most, followed by the combination of drip irrigation, stubble incorporation and NPK. In conclusion, management practices have significant impacts on soil CO2 emission, organic C concentration and C balance in cotton fields. Consequently, appropriate management practices, such as the combination of drip irrigation, stubble incorporation, and either NPK＋OM or NPK could increase soil C storage in cotton fields of Northwest China.

Perovskite/Silicon Tandem Solar Cells: From Detailed Balance Limit Calculations to Photon Management

Energy conversion efficiency losses and limits of perovskite/silicon tandem solar cells are investigated by detailed balance calculations and photon management.An extended Shockley-Queisser model is used to identify fundamental loss mechanisms and link the losses to the optics of solar cells.Photon management is used to minimize losses and maximize the energy conversion efficiency.The influence of photon management on the solar cell parameters of a perovskite single-junction solar cell and a perovskite/silicon solar cell is discussed in greater details.An optimized solar cell design of a perovskite/silicon tandem solar cell is presented,which allows for the realization of solar cells with energy conversion efficiencies exceeding 32%.

Balance Between Jobs and Housing from Perspectives of Real Estate Development and Management and Urban Planning

Jobs-housing balance is the balance between employment and housing. Its philosophy has a long history and development process in urban planning. The concept of jobs-housing balance generally refers to that the number of employed people is roughly equal to the number of occupants within a certain range. This kind of balance is conducive to reducing the commuting time and the change of transportation mode on the way that the employed people spend at work. The realization of jobs-housing balance not only helps to optimize the structure between residence and employment in the region but also is conducive to improving the work enthusiasm and work efficiency of the employed in the region and reducing the commuting costs of workers in the region. In addition, the relegalization of jobs-housing balance also has a certain impact and effect on alleviating the traffic congestion and improving the environment of the region. In summary, the realization of jobs-housing balance has a multi-faceted impact on the development of a city, and promoting the balance between occupation and housing is conducive to promoting the development of the city. The realization of jobshousing balance involves many areas. In this article, In this article, the development history of jobshousing balance is sorted out from perspectives of real estate development and management and urban planning, and its development enlightenment is discussed.

A Study on Development of Balanced Scorecard for Management Evaluation Using Multiple Attribute Decision Making

Recently, most businesses have introduced a system for improving their responsibility to the customers in terms of job improvement. For example, small-quantity batch production increases cost but improve efficiency of management. Companies have been introduced the balanced scorecard to evaluate their management as part of improvement, while they suffer from many trials and errors. Many businesses still have difficulty in introducing balance scorecard concept in their process, but we suggest a method to successfully introduce the balance scorecard. This study aims to suggest a new performance measurement model reflecting relative importance of the key performance indicators for each factor. Our model is applied to several companies in real-world to validate the new model. Also, our study proposes a methodology for an adequate performance measurement using multiple attribute decision making.

Cross-Domain Authentication Scheme Based on Blockchain and Consistent Hash Algorithm for System-Wide Information Management

System-wide information management(SWIM)is a complex distributed information transfer and sharing system for the next generation of Air Transportation System(ATS).In response to the growing volume of civil aviation air operations,users accessing different authentication domains in the SWIM system have problems with the validity,security,and privacy of SWIM-shared data.In order to solve these problems,this paper proposes a SWIM crossdomain authentication scheme based on a consistent hashing algorithm on consortium blockchain and designs a blockchain certificate format for SWIM cross-domain authentication.The scheme uses a consistent hash algorithm with virtual nodes in combination with a cluster of authentication centers in the SWIM consortium blockchain architecture to synchronize the user’s authentication mapping relationships between authentication domains.The virtual authentication nodes are mapped separately using different services provided by SWIM to guarantee the partitioning of the consistent hash ring on the consortium blockchain.According to the dynamic change of user’s authentication requests,the nodes of virtual service authentication can be added and deleted to realize the dynamic load balancing of cross-domain authentication of different services.Security analysis shows that this protocol can resist network attacks such as man-in-the-middle attacks,replay attacks,and Sybil attacks.Experiments show that this scheme can reduce the redundant authentication operations of identity information and solve the problems of traditional cross-domain authentication with single-point collapse,difficulty in expansion,and uneven load.At the same time,it has better security of information storage and can realize the cross-domain authentication requirements of SWIM users with low communication costs and system overhead.KEYWORDS System-wide information management(SWIM);consortium blockchain;consistent hash;cross-domain authentication;load balancing.

Joint position optimization,user association,and resource allocation for load balancing in UAV-assisted wireless networks

Unbalanced traffic distribution in cellular networks results in congestion and degrades spectrum efficiency.To tackle this problem,we propose an Unmanned Aerial Vehicle(UAV)-assisted wireless network in which the UAV acts as an aerial relay to divert some traffic from the overloaded cell to its adjacent underloaded cell.To fully exploit its potential,we jointly optimize the UAV position,user association,spectrum allocation,and power allocation to maximize the sum-log-rate of all users in two adjacent cells.To tackle the complicated joint optimization problem,we first design a genetic-based algorithm to optimize the UAV position.Then,we simplify the problem by theoretical analysis and devise a low-complexity algorithm according to the branch-and-bound method,so as to obtain the optimal user association and spectrum allocation schemes.We further propose an iterative power allocation algorithm based on the sequential convex approximation theory.The simulation results indicate that the proposed UAV-assisted wireless network is superior to the terrestrial network in both utility and throughput,and the proposed algorithms can substantially improve the network performance in comparison with the other schemes.

Optimization of Energy Resource Management for Assembly Line Balancing Using Adaptive Current Search

This paper aimed to present the optimization of energy resource management in a car factory by the adaptive current search (ACS)—one of the most efficient metaheuristic optimization search techniques. Assembly lines of a specific car factory considered as a case study are balanced by the ACS to optimize their energy resource management. The workload variance of the line is performed as the objective function to be minimized in order to increase the productivity. In this work, the ACS is used to address the number of tasks assigned for each workstation, while the sequence of tasks is assigned by factory. Three real-world assembly line balancing (ALB) problems from a specific car factory are tested. Results obtained by the ACS are compared with those obtained by the genetic algorithm (GA), tabu search (TS) and current search (CS). As results, the ACS outperforms other algorithms. By using the ACS, the productivity can be increased and the energy consumption of the lines can be decreased significantly.

平衡计分卡(Balanced Scorecard)新的效绩评价和战略管理系统

平衡计分卡作为新兴的效绩评价系统,在美国应用已近十年。它弥补了传统效绩评价偏重财务指标的不足,增加了评价企业长期成功驱动因素的新指标。从财务、客户、内部业务和学习成长等多角度全面衡量企业效绩,并帮助管理者将组织的战略目标转化为实施的具体指标。着重阐述平衡计分卡的起源、特点、结构和应用及发展趋势。

A Study of the Balanced Scorecard： The Rockwater Case

Over the past decades，various performance appraisal methods have been raised and developed by many scholars and managers for years.It seems that each kind of performance appraisal techniques has its strengths and limitations and none of them is able to avoid all of the pitfalls.Today，driven by the power of innovation，dozens of new companies are trying to reinvent the performance management tools market.This paper analyzes how the Balanced Scorecard (BSC) implemented to provide line managers with a performance appraisal system in the private sector companies through the case study of Rockwater，and critically identify its main strengths and limitations，and then make some recommendations for improvement.

Balance-Peer:负载均衡的结构化P2P模型

为了有效实现结构化P2P系统中数据均衡分布,借鉴并行数据库中数据划分的基本思想,通过在节点加入和数据加入时的存储均衡算法实现大数据量在系统中存储均衡,使得系统存储差异系数大大降低。设计了一个使用数据划分的结构化P2P模型Balance-Peer。在不需要全局信息的情况下,实现动态数据划分方法。实验结果表明了该存储均衡策略是有效的。

A Dynamic Knowledge Model for Nitrogen Fertilizationin Wheat Management

By analyzing and extracting the research progress on nitrogen fertilization in wheat, a dynamic knowledge model for management decision-making on total nitrogen rate, ratios of organic to inorganic and of basal to dressing nitrogen under different environments and cultivars in wheat was developed with principle of nutrient balance and by integrating the quantitative effects of grain yield and quality targets, soil characters, variety traits and water management levels. Case studies on the nitrogen fertilization model with the data sets of different eco-sites, cultivars, soil fertility levels, grain yield and quality targets and water management levels indicate a good performance of the model system in decision-making and wide applicability.

建筑企业管理中的Balanced Scorecard法

本文通过万科企业股份有限公司运用“Balanced Scorecard”法的案例,介绍了“Balanced Scorecard”法在建设企业管理中的应用。从财务绩效、顾客满意、业务流程、创新与成长四个方面进行了分析,提出了整合、发展的建议。

Water and Nitrogen Management Effects on Biomass Accumulation and Partitioning in Two Potato Cultivars

Biomass accumulation and partitioning into different plant parts is a dynamic process during the plant growing period, which is influenced by crop management and climate factors. Adequate knowledge of biomass partitioning is important to manage the crops to gain maximum partitioning of assimilates into plant parts of economic significance, i.e. tubers in potato. This study was conducted using two potato cultivars grown in a sandy soil with center pivot irrigation under full irrigation (FI;irrigation to replenish 100% of water loss by evapotranspiration [ET]) and deficit irrigation (DI;replenish only 80% ET) and two nitrogen(N) rates (pre-plant + in-seasonN rates of 56 + 112 or 168 + 336 kg/ha). Plant samples were taken on 22, 44, 66, and 98 days after seedling emergence (DAE). With high N rate, tuber biomass of ‘Umatilla Russet’ cultivar in relation to total plant biomass varied from 23% - 88% and 25% - 86% over 22 to 98 DAE for the FI and DI treatments, respectively. The corresponding partitioning ranges were 30% - 93% and 38% - 93% at the low N rate. With respect to the‘Ranger Russet’ cultivar, biomass partitioning to tubers ranged from 36% - 82% and 23% - 84% for the FI and DI, respectively, at the high N rate, and 29% - 87% and 39% - 95% at the low N rate. Overall, this study demonstrated that within the range of N rate and irrigation treatments the biomass portioning into tubers was largely similar in both cultivars.

Prospect of energy management system for large steel enterprise

The energy management system(EMS),which acts as the heart of the energy management center of a steel enterprise,is a large computer system focused on the concentrative monitor and control of the production and utilization of energy.Although Chinese steel industry was well developed in the latest decade, so far the levels of the comprehensive energy consumption per ton steel among Chinese steel enterprises are remarkably distinct,and the average value of the comprehensive energy consumption per ton steel of them has still been much higher than the value of those in developed countries.This bad situation,in the opinion of the author,partially results from the poor ability for most Chinese steel enterprises to manage the production and utilization of energy.National policies associated to energy-saving and ejection-decreasing call for steel enterprises to build the EMS;and more and more steel enterprises themselves also desire to achieve EMS projects so that they can optimize their energy production and utilization.Baosteel,the largest and most advanced steel enterprise in China,has got plenty of experience in the EMS due to its incessant practice for more than 30 years in the design,construction,application,and revampment of its EMS.In the present article,the features of an advanced EMS is described and discussed based on the design practice of the EMS of Baosteel Zhanjiang Project.An advanced EMS should be an optimized and integrated system,which possesses of the characteristic of high managing efficiency,enough openness in expansion,friendly interfaces, and simple structure.Furthermore,it could support many-sided applications,e.g.,energy related data mineing,energy network combination and co-supply,application of geographic information technology,and other technical researched on energy-saving aspects.It is known that some energy-related indexes of Baosteel have stood on a high level better than those of some worldwide famous steel enterprises.Moreover,it goes without saying that the indexes of Baosteel Zhanjiang will be better than those of present Baosteel.Therefore, one can easily expect that the new EMS of Baosteel Zhanjiang will be much more advanced,which will be more helpful to fulfil systematiclly saving of energy,to elevate the efficiency of energy utilization,to lower the comprehensive energy consumption per ton steel.

Photodegradation for Nutrient Management in the Dry Tropics

Nutrient limitation in agriculture is a big problem in many tropical areas. Much research has focused on the optimal use of crop residues in agriculture. Recent work indicates that plant residue decomposition rates, including nutrient release rates can be increased by pre-exposure to sunlight. This has potential as a technology to manipulate nutrient release from residues to match crop demands. The possible development and use of this technology is discussed. There is some evidence that this could increase emissions of trace gases, but the increase is thought to be small. Research needs are discussed.

Management Performance Evaluation Model of Korean Construction Firms

Corporate management performance evaluation currently focuses on financial aspects;however, it is necessary to identify and manage elements that contribute to increased economic values in the long run. When it comes to construction firms, most previous research did not cover weighting and estimation approaches for non-financial elements that ultimately influence financial status. In this research, the objective is to develop a management performance evaluation model for Korean construction firms. The model includes financial factors and non-financial factors. This research investigated actual data from Korean construction firmsandclassifiedtheir characteristics. This study is performed in two steps. First, this study derives KPIs for performance measurement techniques and weights the KPIs. And then, it applies the performance data of construction firms to the technique. The findings of this study show that Korean construction firms consider customers to be the foremost priority, converse to previous research which argued that the internal business process was the top priority. The performance measurement results can be fed back into strategies and plans to shed light on issues, reflect on management plans for subsequent years and modify mid to long-term strategies. Therefore, the developed model can help decision-makers effectively revise their management plans.

Production Balance of Ship Erection

A network plan model of ship erection was established based on the network planning technology and the work-package breakdown system. The load-oriented production control method was introduced to build up a throughput diagram model thus it is possible to describe the ship erection process numerically. Based on the digitalized models some cases of production balance of ship erection were studied and three balance indexes were put forward, they are the load balance rate, the input manpower balance rate and the maximum gantry crane operating times. Such an analytic method based on the balance evaluation is the important foundation for digitization and intelligentization of shipyard production management.

Realty Service Contracts and the Legal System of Realty Management in China

The realty(real estate)management of ownership of buildings includes the owner(homeowner)entrust-management and the owner self-management,the former through the way of realty service contracts,the latter through the resolution of the owners’assembly and the owners’committee.The legal disputes of realty service contracts involve balancing interests among the realty service enterprise,individual owner,and all the owners.We should use dynamic balancing of the interests of the three parties to implement the interests of the win-win cooperation rather than the interests of the trade-off of“all or nothing.”The realty service contract is similar to the entrustment contract,both of which are based on the owners’entrustment.The duty to provide realty service is not simply equivalent to fiduciary duty.The realty service contract has the essence of both behavior debt and result debt.For the former,the general provisions of the entrustment contract can be referred to,and for the latter,the general provisions of the contract for work can be referred to.In view of the group characteristics of the realty service contract,owners have no right to terminate the realty service contract at any time but should obey the principle of due process and take the majority mechanism to make a dismissal resolution resolution.The resolutions and management stipulations worked out by the owners’assembly in a majority mechanism,both of which belong to resolution behavior and are legal tools of the owners’autonomy,shall be binding on all the owners.The relationship between the owner,the owner’s assembly,and the owner’s committee is similar to the fiduciary relationship.If the decision made by the owners’assembly or the owners’committee and the management stipulation infringes upon the legal rights and interests of the owners,the injured owner has the right to revocation litigation.At present,residential commodity owners have a relatively low degree of autonomy in China,and legal disputes over realty services are frequent.In the future,we need to perfect the legal incentive and constraint measures,and stimulate the vitality of owner autonomy to promote better implementation of the owner self-management and owner entrust-management.

The Role of Management Accounting in Adding Value to Organisations

The rapid development of digital world has provided modern organisations with challenges and opportunities at the same time.Especially,the use of advanced technology such as internet well improves transparency of many organisations.However,this also brings volatility and uncertainty to an organisation’s business environment,thereby leading to a more complex and time-consuming decision-making process.To solve this problem,two management accounting techniques,ABC System and BSC,have accordingly been adopted by many managers.In this article,the purpose is to briefly discuss some of the challenges faced by organisations;and then,the two initiative management methods are well explained individually with reference to appropriate examples.