Internet pyramid selling causes great harm and has difficulty in obtaining evidence. As most of internet pyramid selling often uses virtual coins to complete cash settlement, criminals can exchange ...virtual coins by controlling visual accounts to transfer funds illegally. The purpose of the work is to mine the key accounts and build evidence chain of personnel and funds. In order to deal with a large number of transaction data, we characterize the virtual currency trading data, which is divided into seven transaction characteristics. The key accounts are these outliers which have too prominent trading behaviour. So we use positive samples to train One Class Support Vector Machine (OCSVM) classification to find trading behaviours' boundary and detect outliers in classification. Then, the correlation between member's information and pyramid selling hierarchical relationship can also be obtained by further linking the trading behaviour of key accounts. Finally, we can screen out the virtual accounts directly controlled by the pyramid selling organization, analyse the flow of funds, investigate and obtain evidence on amount of money involved in pyramid selling. The experimental results show that the classification model cannot only establish the normal model for account transfer behaviour, but also effectively identify abnormal transfer behaviour, thus improving efficiency of investigation and evidence collection for economic investigation departments.
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•A united microbial electrolysis cells-anaerobic system was designed.•The use of microbial electrolysis cells improved dewaterability of digestate.•Electrical regulation induced ...2.8-fold increase in biomethane production.•The united system internal mechanism was speculated.•Syntrophic interaction of microorganisms promoted system performance.
Microbial electrolysis cell (MEC) was integrated into conventional anaerobic digestion (AD) system (i.e. MEC-AD) to electrochemically regulate the co-fermentation of food waste (FW) and sewage sludge (SS). Two anaerobic systems (i.e. MEC-AD, and single AD) were operated in parallel to explore the potential stimulation of electrical regulation in metabolic behaviors of FW and SS and subsequent biomethane production. The highest accumulative methane yield was achieved at an applied voltage of 0.4 V and the FW and SS ratio of 0.2:0.8, increasing by 2.8-fold than those in AD. The combined MEC-AD system mitigated N2O emission and considerably improved ammonia removal and the dewaterability of digestate, in contrast to AD. Scanning electron microscope (SEM) visualized the presence of a large number of rod-like and cocci-like electroactive microbes on the electrode surface. Electrical regulation stimulated the self-growth and proliferation of typical Methanobacterium and Methanosaeta, accordingly contributing to biomethane production greatly.
Orthodontics is a common treatment for malocclusion and is essential for improving the oral health and aesthetics of patients. Currently, patients often rely on the clinical expertise and ...professional knowledge of doctors to select orthodontic programs. However, they lack their own objective and systematic evaluation methods to quantitatively compare different programs. Therefore, there is a need for a more comprehensive and quantitative approach to selecting orthodontic treatment plans, aiming to enhance their scientific validity and effectiveness.
In this study, a combination of the analytic hierarchy process (AHP) and semantic analysis was used to evaluate and compare different orthodontic treatment options. An AHP model and evaluation matrix were established through thorough research and semantic analysis of patient requirements. This model considered various treatment factors. Expert panels were invited to rate these factors using a 1-9 scale. The optimal solution was determined by ranking and comparing different orthodontic treatment plans using the geometric mean method to calculate the weights of each criterion.
The research indicates a higher preference for invisible correction compared to other orthodontic solutions, with a weight score that is 0.3923 higher. Factors such as comfort and difficulty of cleaning have been given significant attention.
The Analytic Hierarchy Process (AHP) method can be utilized to effectively develop orthodontic treatment plans, making the treatment process more objective, scientific, and personalized. The design of this study offers strong decision support for orthodontic treatment, potentially improving orthodontic treatment outcomes in clinical practice and ultimately enhancing oral health and patients' quality of life.
Bone marrow aspiration is a crucial medical procedure to obtain bone marrow samples for diagnosis and treatment. However, traditional bone marrow aspiration needles face several challenges such as ...operational difficulties, inadequate sample acquisition, and patient discomfort. To address these issues, we aimed to design a bone marrow aspiration needle product by using fuzzy analytic hierarchical process (FAHP). The FAHP method was used to identify key factors in the design of the bone marrow aspiration needle, including technicality, usage, and application characteristics. The importance weights and priorities of each factor were determined through questionnaires and interviews with experts. A new bone marrow aspiration needle product was developed based on the results of the FAHP. The new product design considers the weights and priorities assigned to key factors, resulting in improved convenience during operation and a higher success rate of sample acquisition. This was achieved by optimising the structure and material selection of the needle. This study presents a novel bone marrow puncture needle product that effectively integrates the importance and priority of the key factors. It successfully enhances operational performance and patient experience, thereby offering an innovative solution to improve the success rate and therapeutic effect of bone marrow punctures.
A large pool of ammonia in mature leachate is challenging to treat with a membrane bioreactor system to meet the discharge Standard for Pollution Control on the Landfill Site of Municipal Solid Waste ...in China (GB 16889-2008) without external carbon source addition. In this study, an engineering leachate treatment project with a scale of 2,000 m
/d was operated to evaluate the ammonia heat extraction system (AHES), which contains preheat, decomposition, steam-stripping, ammonia recovery, and centrifuge dewatering. The operation results showed that NH
-N concentrations of raw leachate and treated effluent from an ammonia heat extraction system (AHES) were 1,305-2,485 mg/L and 207-541 mg/L, respectively. The ratio of COD/NH
-N increased from 1.40-1.84 to 7.69-28.00. Nitrogen was recovered in the form of NH
HCO
by the ammonia recovery tower with the introduction of CO
, wherein the mature leachate can offer 37% CO
consumption. The unit consumptions of steam and power were 8.0% and 2.66 kWh/m
respectively, and the total operation cost of AHES was 2.06 USD per cubic metre of leachate. These results confirm that heat extraction is an efficient and cost-effective technology for the recovery of nitrogen resource from mature leachate.
•A model for describing the heat transfer characteristics of the ETSC is derived.•A method by performing roughness treatment is proposed to change the emissivity.•Increasing the receiver’s back ...surface emissivity can greatly affect the heat loss.•Real weather test verifies the proposed method in controlling overheat phenomenon.
The receiver’s back surface radiative characteristics of a heat-pipe evacuated-tube solar collector (ETSC) may have a significant influence on its performance. This influence is generally related to the back surface emissivity and temperature; however it has been not studied previously. This paper firstly presents a heat transfer model for the ETSC, which is then derived to characterize the relationship between the heat loss and the back surface emissivity of the ETSC. A steady state experiment has been also performed to measure the heat loss of ETSC with different back surface emissivity values. The experimental results indicate that the heat loss of the ETSC increases with the increase of the back surface emissivity, but the rate of increase differs for different operation temperatures. When the back surface emissivity increases from 0.03 to 0.12, the heat loss of ETSC only increases by 31% when the operation temperature is below 100°C, but the heat loss will increase to 96% when the operation temperature is over 200°C. This means that the change of back surface emissivity can significantly affect the performance of the ETSC at higher temperature but affect little at lower temperature. Based on this, a novel method by performing roughness treatment on the receiver’s back surface is proposed to solve the overheating problem of ETSC in summer. Two solar water heaters including 6 ETSCs with standard and roughness-treated tubes were tested under real weather condition. Experiment reveals that when the water temperature in tank is below 60°C, the two solar water heaters own similar temperature change. But when the temperature is over 80°C, the solar water heater with roughness-treated tube shows obviously lower temperature increase than that with standard tube. Therefore, it is very effective to prevent overheating of some solar water heaters used in high latitudes in summer by increasing the receiver’s back surface roughness.
Bad information filtering is conducive to creating a healthy network. A two-level filtering method based on topic and sensitive words is proposed. In the first stage, the network text is filtered by ...using thesaurus, by setting the weight of different topics. In the second stage, according to the frequency, position and sensitivity of sensitive words, the value of bad tendency is obtained by weighting the web text. Finally, taking the text set recognition of bad financial publicity content in the network as an example, the result proves that it can improve the efficiency and accuracy of filtering of bad investment information.
The wan Internet storage system based on Distributed Hash Table uses fully distributed data and metadata management, and constructs an extensible and efficient mass storage system for the application ...based on Internet. However, such systems work in highly dynamic environments, and the frequent entry and exit of nodes will lead to huge communication costs. Therefore, this paper proposes a new hierarchical metadata routing management mechanism based on DHT, which makes full use of the node stabilization point to reduce the maintenance overhead of the overlay. Analysis shows that the algorithm can effectively improve efficiency and enhance stability.
The traditional network theory is unsuitable for money laundering path analysis because of the complexity of financial transaction. The abnormal accounts are identified only by effectively mining the ...characteristics of fund flow. The importance of transaction node in the whole illegal capital flow is equivalent to that of the connection among these nodes. Through combining the page rank algorithm with the characteristics of fund flow, an improved weighted and iterative initial value mechanism is designed to calculate the transaction heat value of the account, thus the abnormal capital transaction account is screened out. When the method is applied to a money laundering case, the results show the improved page rank algorithm can effectively screen out the key account nodes in the money laundering network and provide clues for the monitoring of money laundering crimes.
Money laundering is an activity of transferring money through fraud and concealment. And its behaviour is different from normal transaction. The key to identifying money laundering crime is to find ...illegal account from massive capital flow data. The paper studies a method to identify the money laundering nodes by constructing the structural features of the capital flow network. According to the characteristics, we define the calculation methods of node outgoing, incoming and connectivity in the capital flow network, and identify the key nodes. The experimental results show that this method can find abnormal account from large-scale capital transaction data. Although the accuracy needs to be improved, it can help extract evidence of money laundering by ranking the weight and analyzing the capital flow from high-weight account.