Explore the vast range of titles available.

Access to a reliable and safe domestic water supply is a serious challenge for many developing countries worldwide. In the capital of Vietnam, Hanoi, the municipal government is facing a number of difficulties in providing sufficient water in a sustainable manner due to the increasing urban population and the serious pollution of both surface and groundwater resources, but this is also due to a lack of resources to invest in the supply system. This study aimed to investigate water users’ willingness to pay for the improvement of Hanoi’s domestic water supply system. A contingent valuation process based on a survey of 402 respondents was used to explore citizens’ willingness to pay (WTP) for the improvement of their urban water supply. The results show that Hanoi’s urban communities (more than 90%) were generally satisfied with the quantity of their water supply, but tended to be dissatisfied with its quality, with 80% of the respondents using advanced water purifiers before drinking and cooking. Respondents were also concerned about the overall reliability of the service, with 40% of respondents indicating that they received no check and maintenance service. A WTP regression model was developed based on the survey findings. The average WTP is 281,000 dong/household/month (approximately 12.2 USD at the exchange rate of 1 USD to about 23,000 VND), equivalent to 1.4% of the average household income at the end of 2019, indicating the level of affordability of monthly water payments among Hanoi citizens.

The purpose of the work is to assess both the position and tendency of the competitiveness of Mexican pork carcass versus the foreign supply, as well as the relationship between this commercial advantage, the domestic production and exportation thath may a llow proposing strategies to enhance this activity in the medium term. To achieve this goal, the four competitiveness indices postulated by the Inter - American Institute for Cooperation on Agriculture were estimated, and the degree of association between va riables was determined using Pearson´ s coefficient. It was found that the volume of the primary supply of pork positions Mexico in the fifteenth place worldwide, while as an exporter country it occupies the forty - second place; that the exportation of this meat has as its main destinations the markets of the United States of America and Japan, and that the domestic production has a low level of competitiveness in the international market. It was also found that on the behavior of the production and exportati on of Mexican pork influences factors linked to the particularities of the market and of the commercial process, which determine both productivities, as the generation of exportable surpluses of pork carcass and of value for México s economy.

This paper presents the objectives of reclaimed water use in China and the current quantities used at the national and provincial levels. Using 2015 statistical data as an example, this paper studies the influences of water resources quantity, gross domestic product and policy promotion hierarchy on reclaimed water use in all provincial administrative regions in China. Reclaimed water use in Beijing and Jiangsu are presented as two representative examples. China's reclaimed water experience can provide some guidance for other countries facing similar water resource situations.

The main purpose of this study was to investigate whether machine learning can be used to detect leak sounds in the field. A method for detecting water leaks was developed using a convolutional neural network (CNN), after taking recurrence plots and visualising the time series as input data. In collaboration with a pipeline restoration company, 20 acoustic datasets of leak sounds were recorded by sensors at 10 leak sites. The detection ability of the constructed CNN model was tested using the hold-out method for the 20 cases: 19 showed more than 70% accuracy, of which 15 showed more than 80%.

With per capita water resources at only around a quarter of the world average, China’s water resources are limited and unevenly distributed. Past research on water resource utilization has mainly focused on industrial water use (agriculture and industry), water plant ownership efficiencies (private or public operation), or water resources and economic production; however, there have been few studies focused on water supply livelihood. Therefore, this paper considered both industrial production water services, non-production water services (public sector and residential water use), and water leakage losses, which is a water supply problem seldom mentioned in other studies. An undesirable directional distance function (DDF) dynamic data envelopment analysis (DEA) model was employed for the dynamic analysis as it was able to deal with both desirable and undesirable outputs at the same time. The model examined collected water supply and water leak efficiency data from 30 Chinese provinces/municipalities from 2007 to 2018, from which it was found that (1) Beijing, Gansu, Guangdong, and Ningxia had efficient water supply and water leak losses from 2007 to 2018 and the most improved province was Jiangxi; (2) the eastern provinces, in general, had better water efficiencies and the central and western provinces needed greater improvements; and (3) the lowest water leakage loss efficiencies were in Inner Mongolia, Jiangxi, and Heilongjiang, all of which required significant improvements.

Domestic supply wells meet much of the world’s potable water demand. These wells tend to fail as regional groundwater levels decline from intensive agricultural groundwater use, especially during drought when additional pumping occurs. This work examines approaches for addressing impacts on domestic wells in much of the San Joaquin Valley in California, USA, where groundwater management is now required. Mitigation actions and their costs are considered to allow continued well operations as groundwater levels decline to target levels specified in groundwater management plans. The estimated total mitigation cost for groundwater-level declines to the planned management targets ranges from$42 to $ 96 million depending upon well retirement age. If groundwater levels decline further to defined limits below the management targets allowed during drought, costs increase by$78 to $ 153 million. There will likely be competition for specialized labor to implement the mitigation actions since agricultural wells will also be affected. Unless current groundwater management plans become more stringent and specify shallower groundwater depth targets, proactive mitigation should be considered for the most vulnerable areas to prevent impacts from growing beyond the capacity for timely mitigation and to avoid widespread failure of rural domestic water supplies. The cost of mitigation for impacted wells is estimated to be less than 2% of the benefit to agriculture from being allowed to pump groundwater in excess of management targets during a multiyear drought.

Nontuberculous mycobacteria (NTM) refer to mycobacteria other than Mycobacterium tuberculosis and Mycobacterium leprae. Some NTM are known to cause pulmonary and skin diseases. As NTM are prevalent in water supply systems, the health burden of waterborne NTM is concerned. However, little is known about NTM in building plumbing. This study revealed the abundance and diversity of NTM in building plumbing by using culture-dependent and culture-independent approaches. Moreover, the chlorine susceptibility of NTM isolates in tap water was evaluated. The increase in the abundance of Mycobacterium spp. was observed in some taps after 24 h of stagnation, indicating that NTM could have the potential to regrow in building plumbing. While Mycobacterium mucogenicum and Mycobacterium avium were detected by cultivation, amplicon sequencing of NTM-specific hsp65 genes revealed that Mycobacterium gordonae was dominant in most of the samples, which was not detected by cultivation. The chlorine susceptibility experiment demonstrated that NTM strains related to M. avium and M. mucogenicum were 119 and 426 times more tolerant to chlorine than Escherichia coli, respectively. As M. mucogenicum, M. avium, and M. gordonae are regarded as opportunistic pathogens, intensive monitoring of NTM in tap water in building plumbing is necessary.

This paper proposes a hybrid NBO–SDRN approach for a solar PV (SPV) array fed water pumping system utilizing a single-ended primary inductor converter (SEPIC) based BLDC motor drive. The proposed hybrid method combines Namib beetle optimization algorithm (NBO) and spiking deep residual networks (SDRN). Commonly, it is named the NBO–SDRN technique. The main goal of the NBO–SDRN method is enhanced energy efficiency, improved control algorithms, and optimal utilization of available solar energy resources. This paper focuses on integrating a SEPIC converter-based brushless DC motor drive in such systems to optimize energy conversion, enhance control, and promote environmentally friendly water supply. The BLDC (brushless direct current) motor drive and advanced control algorithms enable precise speed and torque control, improving overall energy efficiency and adaptability to varying water demand. By then, the NBO–SDRN method is done in the MATLAB working stage, and the execution is calculated with the present procedures. The proposed approach performs better outcomes in all existing singular spectrum analysis (SSA), heap-based optimization (HBO), and bee circle search algorithm (CSA) methods. From the result, the NBO–SDRN method-based efficiency is 95% higher than the existing methods.

Fresh groundwater, as an essential component of global water resources and a special type of mineral wealth, has a whole set of features that affect social infrastructure, the economy and the environmental well-being of the population. At the same time, groundwater is vulnerable and limited despite its replenishable nature and vast reserves. Recently, in some countries, the practice of extracting groundwater resources by private individuals on their territory has been actively spreading, but not in all states. This is considered acceptable and is enshrined in national regulations. Uncontrolled exploitation of aquifers by small water users can affect the safety of ecosystems and the depletion of drinking groundwater reserves. In this regard, the state policy and system for regulating access to groundwater resources for all subsoil users should be based on a well-thought-out concept. This article is devoted to the organizational, economic, and regulatory issues of groundwater extraction by individuals for their own needs in the Russian Federation. A comparative analysis of the state approach to groundwater extraction by private individuals in other states (mainly in the example of Germany and China) is made. The latest trends in legislation in this area are analyzed, shortcomings in the system of state regulation of groundwater use are identified, and mechanisms for legalizing the activities of individual water users are proposed. Global groundwater regulation should be based on rationality, control, safety, protection, sustainability, and future generations’ care.