Analysis of Peukert and Liebenow Equations Use for Evaluation of Capacity Released by Lithium-Ion Batteries

The Peukert and Liebenow equations were obtained from experimental studies of lead–acid batteries. Currently, they are used to evaluate capacity released by batteries of other electrochemical systems (alkaline, lithium-ion, etc.), as well. In this paper, it is experimentally proved that for lithium-ion batteries, the Peukert equation can be used in two intervals of the discharge currents. The first interval includes currents from 0.2Cn up to the first inflection point of the experimental function of the battery capacity dependence on the discharge currents C(i). The second interval covers currents from the second inflection point of the experimental function C(i) up to the maximum currents that were used in the experiments. For some lithium-ion batteries, the range of low discharge currents, where the Peukert equation is applicable, is quite large and often completely covers the range of the discharge currents used in practice for these batteries. Therefore, many authors, when estimating the capacity of lithium-ion batteries, use the Peukert equation. However, the research in this paper shows that for lithium-ion batteries, the use of the Peukert equation is limited to the two discharge current ranges indicated above. Unlike the Peukert equation, the Liebenow equation can be used only in the range of small discharge currents from zero to the first inflection point of the experimental function C(i).

Identifying the causes of waterlogging on people's perception towards a resilient community: a case study on Pabna Municipality, Bangladesh

PurposePabna is suffering from waterlogging problems from ancient times. The previous Drainage Master Plan was failed due to the lack of reflection of the general people of Pabna Municipality. As a result, this study focuses on identifying the causes of waterlogging in people's eyes. This paper will help the local authority and planners eradicate the waterlogging problem and build a planned and resilient community.Design/methodology/approachBoth primary and secondary data were used for the study. Present drainage pattern, topology climatic elements were collected from the journals, websites and Municipal Ingratiated Development Plan (MIDP), Pabna-2008. The sample size was 246, and this respondent was surveyed. By the survey, the people's perception of waterlogging was collected. For that, five independent variables and one dependent variable were determined. These variables were determined by previous studies, reconnaissance survey of the study area. It used multiple linear regression and the correlation method; the causes of waterlogging were determined.FindingsThe study found solid waste disposal into the drainage, absence of operation and maintenance system, small discharge capacity with blocked in the current drains, nonappearance of combined drainage network of roadside drains and unplanned drainage system as the leading causes of waterlogging from the perception of the people. Also found that the absence of operation and maintenance system, solid waste disposal into the drainage and unplanned drainage system as the influencing causes on small discharge capacity with blocked in the current drains.Originality/valueThis study has focused on people's perceptions rather than secondary data. That is why this study will significantly impact eradicating the waterlogging problem from the Pabna Municipality and will carry out the core problems without any bias. This will lead to a sustainable, planned and resilient community.

DIFFERENCES OF CULEX SPP AND AEDES SPP LARVAE MORTALITY RATES ON THE USE OF THEMEFOS

Eradication of the mosquito vectors that cause several diseases is still being carried out today where methods are still being developed. This research aims to identify the mortality rate of Culex spp. and Aedes spp. larvae for the use themefos or abate with sowed and wrapped of filter paper. The author uses quasi-experimental to observe that mortality. The design was devided into two groups, giving themepos/abate with a national dose of (1gr/10 liters of water) in 24 hours with threatment sowed and wrapped of filter paper through the analysis of varians/annova test to observe the varians of the time of mortality of Culex spp. and Aedes spp. larvae as well as probit analysis to see the probability of time of the larvae’s death.The result of this research is no defference in the mortality of Culex spp. and Aedes spp. larvae for the uses of themefos/abate with sowed and wrapped of filter paper. The authors suggestion is giving themefos or abate by wrapping filter paper preverably for larvae in a stagnant water such as Aedes spp larvae because it does not provide residual granules in water reservoirs used for human activities while the used of themepos/abate with sowed can also be used for a stagnant water or has a small discharge.

Spontaneous initiation of debris flow surges from sedimentary deposits

<p>Spontaneous initiation of debris flow surges from sedimentary deposits</p><p>Wang Baoliang<sup>1 </sup>, Li Yong<sup>2</sup>, Guo Xiaojun<sup>2</sup></p><p>1 Yellow River Engineering Consulting Co., Ltd., Zhengzhou, 450004, China</p><p>2 Key Laboratory of Mountain Hazards and Surface Process / Institute of Mountain Hazards and  Environment, Chinese Academy of Sciences, Chengdu, 610041, China</p><p> </p><p>We report here that a small gully of sedimentary deposit has spontaneously produced a sequence of debris flow surges in great variety of appearances. The event occurred in a tributary gully of 0.16km<sup>2</sup>, without slope failures and rainstorms; the only triggering force was the groundwater at small discharge (0.5L/s). Individual surges originated separately from the sediment in different manners and appeared in a variety of flow regimes and material compositions(Fig.1). We’ve taken a detailed scrutiny on the whole processes, i.e., the surge sequence spontaneously occurring in the stream (Fig.2), and suggested a mechanism for the surge scenario. It is proposed that the sediment is heterogeneously composed of blocks of granular aggregates, featured by the grain size distribution (GSD). With different GSD parameters, sediment blocks have different critical condition of liquefaction or fluidization, which determines the manner of surge initiation (Fig.3). Fine grains are easily to run out with infiltration to form slurry and lubricate the substrate sediment layer, facilitating the mobility of succeeding surges; while coarse grains collapse as Coulomb failure and turn into high concentrated surges. And variation of the substrate granular structure causes on and off of the surges. In summary, it is the randomness of GSD and block of sediment that lead to the variety of surge initiation; and the initiation and motion of tributary surges provides a vivid scenario for intermittent surges in the mainstream channel.</p><p> </p>

Virtual Signal-Based Pulse Discrimination in Micro-Electro-Discharge Machining

Owing to the contaminations in the small discharge gap of micro-electro-discharge machining (μEDM), generation of nonuniform nature of discharge pulses is more significant than in macro-EDM. To address the contribution in material removal of workpiece by each of these pulses, a pulse discriminating (PD) system which discriminates them into contributing and noncontributing types is generally used. Developing a PD system in μEDM is a time-consuming process that requires an availability of continuously running machine. Such requirement could be eliminated if virtual signals, similar to the actual once, are made available and provided continuously to the PD system developer. An innovative idea of generating such virtual signals, based on ni multisim, is, therefore, proposed and a robust PD system based on these signals is developed and validated. The strategy for discriminating the pulses in various types is developed through virtual instrumentation in ni labview. The robustness is validated in terms of its applicability over a wide range of parametric settings, acquisition length, and time.

Small Hydro Power Schemes: Technical Aspects

<p>Small hydro systems play a major role in meeting power requirements of remote, isolated, hilly areas in a decentralized manner by tapping water streams, rivulets and canals of small discharge. Small hydroelectric system captures the energy in flowing water and converts it to electricity.</p>Of all the non-conventional renewable energy sources, small hydro stands first as it is more resourceful, reduces system losses, environment friendly, non-consumptive and source is renewable due to their enormous advantages over large hydro and other power plants, lot of small hydro-power plants have come up across the world to meet the ever increasing demand of electrical energy. Lowering the high initial cost of the small hydro-power plants and its popularization is today’s challenges. This paper describes basic techniques design of the small hydro-power development.

Coating Onto a Prewet Substrate With Low Weber Number Liquid Curtain

In recent years, miniaturization and high precision of the LCD screen used for small display has been developed fast. The thin and high-precision film covering the LCD screen is manufactured by slide coating. In slide coating, however, the distance between the slot and the substrate is too small. On the other hand, curtain coating can avoid the influence of the mechanical disturbance and is also a good method for coating on rugged substrate. Nevertheless, curtain coating has not been applied to the LCD screen because the liquid curtain with small discharge, i.e. small Weber number, causes instabilities of the flow and the free surfaces. In the present study, we performed the experiment of the liquid curtain bridged between the exit of slot die and moving roller under very small Weber number (We ∼0.1). It is found that the surface waves are reduced by using a roller pre-wetted by mists and by changing the viscosity of the liquid. Also, the coating window can be drawn in a plane of surface tension and viscosity. Finally, we tried to explain these phenomena by analyzing the equations of liquid curtain.