Hasil untuk "River, lake, and water-supply engineering (General)"

Haimo Joehri

This paper gives an overview about aspects of mechanical engineering of undulators. It is based mainly on two types that are used in the SwissFEL facility. The U15 Undulator is an example of an in-vacuum type and the UE38 is an APPLE-X type. It describes the frame, the adjustment of the magnets with flexible keepers and the adjustment of the whole device with eccentric movers.

Md Saeed Siddik, Hao Li, Cor-Paul Bezemer

Context: Jupyter Notebook has emerged as a versatile tool that transforms how researchers, developers, and data scientists conduct and communicate their work. As the adoption of Jupyter notebooks continues to rise, so does the interest from the software engineering research community in improving the software engineering practices for Jupyter notebooks. Objective: The purpose of this study is to analyze trends, gaps, and methodologies used in software engineering research on Jupyter notebooks. Method: We selected 146 relevant publications from the DBLP Computer Science Bibliography up to the end of 2024, following established systematic literature review guidelines. We explored publication trends, categorized them based on software engineering topics, and reported findings based on those topics. Results: The most popular venues for publishing software engineering research on Jupyter notebooks are related to human-computer interaction instead of traditional software engineering venues. Researchers have addressed a wide range of software engineering topics on notebooks, such as code reuse, readability, and execution environment. Although reusability is one of the research topics for Jupyter notebooks, only 64 of the 146 studies can be reused based on their provided URLs. Additionally, most replication packages are not hosted on permanent repositories for long-term availability and adherence to open science principles. Conclusion: Solutions specific to notebooks for software engineering issues, including testing, refactoring, and documentation, are underexplored. Future research opportunities exist in automatic testing frameworks, refactoring clones between notebooks, and generating group documentation for coherent code cells.

Ana Arauzo

This lecture presents an overview of the basic concepts and fundamentals of Engineering Materials within the framework of accelerator applications. After a short introduction, main concepts relative to the structure of matter are reviewed, like crystalline structures, defects and dislocations, phase diagrams and transformations. The microscopic description is correlated with physical properties of materials, focusing in metallurgical aspects like deformation and strengthening. Main groups of materials are addressed and described, namely, metals and alloys, ceramics, polymers, composite materials, and advanced materials, where brush-strokes of tangible applications in particle accelerators and detectors are given. Deterioration aspects of materials are also presented, like corrosion in metals and degradation in plastics.

Amr S. Mohamed, Emily Nguyen, Deepa Kundur

Amidst the growing demand for implementing advanced control and decision-making algorithms|to enhance the reliability, resilience, and stability of power systems|arises a crucial concern regarding the safety of employing machine learning techniques. While these methods can be applied to derive more optimal control decisions, they often lack safety assurances. This paper proposes a framework based on control barrier functions to facilitate safe learning and deployment of reinforcement learning agents for power system control applications, specifically in the context of automatic generation control. We develop the safety barriers and reinforcement learning framework necessary to establish trust in reinforcement learning as a safe option for automatic generation control - as foundation for future detailed verification and application studies.

FENG Huan, SU Huaying, LIU Chenliang et al.

Based on the analysis of the importance of different time periods for flood control, this paper proposed a solution approach that segments flood control into key and non-key periods. An efficient solution algorithm for the flood control model that coupled dynamic programming and grey wolf algorithm was proposed through a bidirectional feedback loop mechanism, which used the grey wolf algorithm to provide boundary conditions for the dynamic programming, while the dynamic programming influences the fitness values of the grey wolf algorithm. The extreme and frequent floods of Goupitan Reservoir were solved. Compared to the actual situation, the peak flow of the control section was reduced by 42% and 43%. The time computation of the two scenarios was 19.54 s and 71.27 s, respectively, while that of the dynamic programming is 90~141 s and 300~500 s with the same accuracy. This indicated that the coupled algorithm balanced solution efficiency and accuracy by combining the strengths of both dynamic programming and grey wolf algorithm, providing a new solution for the flood control scheduling model of the reservoir.

Ari Azhar Maulana, Harnita Rosalina

Rainfall plays a crucial role in shaping the weather in Indonesia, influenced by factors such as latitude, elevation, wind patterns, land and water distribution, as well as topography. Rising temperatures contribute to the increased intensity of extreme rainfall, amplifying the potential risk of disasters. Therefore, it is necessary to conduct analyses to predict weather based on historical time series data. This study aims to identify short-term rainfall patterns and trends using the SARIMAX method. The initial stage involves data processing and splitting the data into training data (2005-2014) and test data (2015-2019). Time series decomposition is then performed to identify patterns, followed by period identification and stationarity testing using the ADF test. The SARIMAX model is selected based on the lowest AIC value, followed by parameter estimation and diagnostic tests. Rainfall predictions are evaluated using model performance evaluation methods, while inferential statistics are used to describe population attributes through confidence intervals. The forecasting results show that using the SARIMAX (0, 0, 1)(0, 1, 1, 12)12 model for short-term rainfall prediction achieved the best performance with the smallest MSE, MAE, and MAPE values on the test sample with a 95% confidence level. Repeating rainfall patterns with a mid-year decline and significant variation in magnitude were identified from the sample data for August 2020-2027, with the lowest rainfall at 39.05 mm and the highest at 397.03 mm in December. The implications of this study support efforts to mitigate natural disasters due to unexpected weather changes by integrating this model into early warning systems and water resource planning.

HUANG Lixiang, WANG Jianquan, DI Qimeng et al.

The ecological footprint and ecological carrying capacity of water resources are of key directive significance for the balance between supply and demand of regional water resources and are increasingly important in the construction of ecological civilization and sustainable water resource utilization. However, existing research lacks accounting and evaluation of the ecological footprint of water resources in Shandong Province. Based on the ecological footprint model of water resources and the system dynamic model of water supply and demand in Shandong Province, the ecological footprint and ecological carrying capacity of water resources in Shandong Province from 2001 to 2022 are calculated and evaluated. The results show that: ① From 2001 to 2022, the ecological footprint of water resources in Shandong Province showed a fluctuating downward trend, with the average per capita ecological footprint and the average per capita ecological carrying capacity of water resources being 0.379 hm²/person and 0.106 hm²/person, respectively, showing a slow downward trend. As a result, the per capita ecological profit and loss of water resources were both negative (with an average of-0.273 1 hm²/person), indicating that there were ecological losses of water resources in all years. Water resources in Shandong Province have always been in an unsustainable state of utilization, enduring significant ecological losses of water resources. ② From 2001 to 2022, the ecological pressure index of water resources in Shandong Province was greater than 1 and showed an upward trend, with an average value of 3.581. The ecological and economic coordination index of water resources had little fluctuation, with an average value of 1.232. The ecological footprint intensity of water resources showed a significant downward trend, with an average value of 0.143 hm²/10⁴ RMB and a decrease of up to 90.9%. Shandong Province suffered from significant ecological pressure on water resources from 2001 to 2022, and water resources were in an unsafe state of utilization. The ecological and economic coordination of water resources was good, but there was still a gap from the optimal ecological and economic coordination of 1.414. It is necessary to further strengthen the ecological and economic coordination of water resources in Shandong Province, and the efficiency of water resource utilization has been greatly improved. ③ Shandong Province needs to invest a lot of effort in promoting water-saving facilities, adopting water-saving cultivation techniques, and improving water efficiency. In terms of domestic water use, as the population is constantly growing, it is necessary to increase efforts in cultivating public awareness of water-saving, vigorously promoting the protection of existing water resources, and popularizing water-saving measures in the whole society. Only by making the awareness and behavior of water-saving deeply rooted in people's hearts can we better and more effectively promote the sustainable use of regional water resources.

GAO Aiping, HUANG Tinglin, MA Xu et al.

Flood season runoff is an important factor affecting reservoir operation, and timely understanding of the runoff transport and the corresponding water quality responses during flood season can provide suggestions for reservoir operation. In-situ field monitoring is conducted at the Jinpen Reservoir, and water quality is analyzed through photometry and atomic absorption to study the reservoir runoff. It is found that the runoff's transport progress and the location where it enters the reservoir area are mainly influenced by its volume. The inflow on October 3 is three times larger than that on April 4 and 2.6 times larger than that on June 3, while the TP content is five times higher than that on June 3, and the COD_Mn is 1.8 times and 1.7 times higher than that on these two days, respectively, indicating that the TP and COD_Mn in the inflow are related to its volume. The inflow on April 4 and June 3 is nearly the same, but the TN and NO₃-N on April 4, when the initial runoff happens, are 2.2 times and 1.7 times larger than that on June 3 respectively, indicating that TN and NO₃-N are greatly influenced by the initial runoff. On October 3, the runoff contains over 70% of suspended particles larger than 10 μm. The turbidity reduction turned slow when it decreased to 30 NTU after the runoff entered the reservoir. Moreover, the pollutants carried by the particle are inversely proportional to the particle's size, leading to substandard water quality in the reservoir during the flood season. Under the rapid deterioration of reservoir water quality during the flood season, the quality of the water supply can be improved by releasing the high-turbidity water carried by the runoff through the flood discharge tunnel to ensure clean water storage and using elevated water intakes.

Christian Himpe

Metadata management for distributed data sources is a long-standing but ever-growing problem. To counter this challenge in a research-data and library-oriented setting, this work constructs a data architecture, derived from the data-lake: the metadata-lake. A proof-of-concept implementation of this proposed metadata aggregator is presented, too, and also evaluated.

A. I. Vedenev, O. Yu. Kochetov, A. A. Lunkov et al.

Simultaneous measurements of underwater and airborne noises produced by Griffon Hoverwork BHT130 hovercraft were carried out in environmentally sensitive area - wildlife preserve in the area of the Ural River estuary near the Caspian Sea shelf. Measurements were organized to assess the possible negative impact of noise from hovercraft on fish and birds in wildlife preserve. The particle velocity of underwater noise was estimated by using a gradient-type vector receiver. That was a distinctive aspect of the underwater noise studies since the majority of fish perceives the sound in terms of vibration of particles, and only a few as the pressure. Using synchronous recording of underwater and airborne noises, the mutual correlation of these data was investigated. The obtained correlation levels between underwater and airborne noises produced by hovercraft can be used for simplified estimation of the upper boundary of underwater noise level by measuring levels of airborne noise. The measured and estimated maximal levels of underwater noises of hovercraft are considerably lower than noises from conventional vessels with underwater engines, that makes hovercraft attractive alternative for use in locations with high underwater noise requirements, such as Ural River estuary and Caspian Sea shelf.

Shan-hu Jiang, Lin-yong Wei, Li-liang Ren et al.

A comprehensive assessment of representative satellite-retrieved (Integrated Multi-satellite Retrievals for Global Precipitation Measurement (IMERG) and Tropical Rainfall Measuring Mission Multi-satellite Precipitation Analysis (TMPA)), reanalysis-based (fifth generation of atmospheric reanalysis by the European Centre for Medium Range Weather Forecasts (ERA5)), and gauge-estimated (Climate Prediction Center (CPC)) precipitation products was conducted using the data from 807 meteorological stations across mainland China from 2001 to 2017. Error statistical metrics, precipitation distribution functions, and extreme precipitation indices were used to evaluate the quality of the four precipitation products in terms of multi-timescale accuracy and extreme precipitation estimation. When the timescale increased from daily to seasonal scales, the accuracy of the four precipitation products first increased and then decreased, and all products performed best on the monthly timescale. Their accuracy ranking in descending order was CPC, IMERG, TMPA, and ERA5 on the daily timescale and IMERG, CPC, TMPA, and ERA5 on the monthly and seasonal timescales. IMERG was generally superior to its predecessor TMPA on the three timescales. ERA5 exhibited large statistical errors. CPC provided stable estimated values. For extreme precipitation estimation, the quality of IMERG was relatively consistent with that of TMPA in terms of precipitation distribution and extreme metrics, and IMERG exhibited a significant advantage in estimating moderate and heavy precipitation. In contrast, ERA5 and CPC exhibited poor performance with large systematic underestimation biases. The findings of this study provide insight into the performance of the latest IMERG product compared with the widely used TMPA, ERA5, and CPC datasets, and points to possible directions for improvement of multi-source precipitation data fusion algorithms in order to better serve hydrological applications.

LI Wenhuan, ZHI Huanle, JIANG Shuihua et al.

Since the rapid economic development within the dike is inconsistent with the level of flood control management,dike break is prone to occur under over-standard floods and causes serious losses of life,economy,and ecological environments.Taking a key dike in the Poyang Lake area as an example,this paper proposed a dike-break-induced flood evolution simulation method based on hydrodynamics.The proposed method adopted the MIKE 21 software for dike-break-induced flood evolution analysis.The roughness of the underlying surface was determined reasonably according to different types of land use.Meanwhile,quantitative evaluation models of life,economic,and environmental losses that had clear physical meaning were established in the Python platform.The research results can provide references for flood warning and risk management and control of flood disasters in protected areas.

L. Siddharth, Jianxi Luo

Aiming to support Retrieval Augmented Generation (RAG) in the design process, we present a method to identify explicit, engineering design facts - {head entity :: relationship :: tail entity} from patented artefact descriptions. Given a sentence with a pair of entities (based on noun phrases) marked in a unique manner, our method extracts the relationship that is explicitly communicated in the sentence. For this task, we create a dataset of 375,084 examples and fine-tune language models for relation identification (token classification) and elicitation (sequence-to-sequence). The token classification approach achieves up to 99.7 % accuracy. Upon applying the method to a domain of 4,870 fan system patents, we populate a knowledge base of over 2.93 million facts. Using this knowledge base, we demonstrate how Large Language Models (LLMs) are guided by explicit facts to synthesise knowledge and generate technical and cohesive responses when sought out for knowledge retrieval tasks in the design process.

Sankalpa Timilsina, Justin Presley, David Reddick et al.

As the growth of genomics samples rapidly expands due to increased access to high resolution DNA sequencing technology, the need for a scalable platform to aggregate dispersed datasets enable easy access to the vast wealth of DNA sequences available is paramount. In this work, we introduce and demonstrate a novel way to use Named Data Networking (NDN) in conjunction with a Kubernetes cluster to design a flexible and scalable genomics Data Lake in the cloud. In addition, the use of the NDN Data Plane Development Kit (DPDK) provides an efficient and accessible distribution of the datasets to researchers anywhere. This report will explain the need to deploy a Data Lake for genomics data, what is necessary to deploy successfully, and detailed instructions to replicate the proposed design. Finally, this technical report outlines future enhancement options for further improvements.

CUI Fan, KOU Xinyue, FENG Youbin et al.

In order to resolve the contradiction between the high demand for water resources,water ecology and water environment in the Guangdong-Hong Kong-Macao Greater Bay Area (GBA) and the insufficient supervision capabilities in the water conservancy industry,and achieve the transformation from passive management to active management of key drinking water sources in the GBA,this paper carries out supervisory monitoring of key drinking water sources through remote sensing macro monitoring,UAV cruise monitoring,fixed-point monitoring and other intelligent monitoring technology system.The results show that:①After application of a supervisory monitoring technology system for key drinking water sources,the full-coverage,dynamic and quasi-real-time monitoring of 35 key water sources in the GBA is realized,and the risk sources and water problems can be identified efficiently.②For identifying five suspected risk sources in water source areas,namely construction projects,key river (reservoir) tributaries,temporary shipping stops,material stacking places,agricultural production activities by remote sensing macro monitoring and UAV cruise monitoring,the accuracy rate is 65.7%.③For the chlorophyll a and COD_Mnmonitoring of the water source of main Guangzhou-Dongguan-Huizhou Dongjiangbei River by remote sensing macro monitoring and artificial fixed-point monitoring during the same period,the monitoring results of the two technical means are in good agreement.Therefore,with application of the technology system in supervision and management of key drinking water sources,the smart water conservancy supervision and business management are deeply integrated,and the effective technical means for supervision and management are available.

K. Zhao, E. W. Tedford, M. Zare et al.

Methane ebullition (bubbling) from lake sediments is an important methane flux into the atmosphere. Previous studies have focused on the open-water season, showing that temperature variations, pressure fluctuations and wind-induced currents can affect ebullition. However, ebullition surveys during the ice-cover are rare despite the prevalence of seasonally ice-covered lakes, and the factors controlling ebullition are poorly understood. Here, we present a month-long, high frequency record of acoustic ebullition data from an ice-covered lake. The record shows that ebullition occurs almost exclusively when atmospheric pressure drops below a threshold that is approximately equal to the long-term average pressure. The intensity of ebullition is proportional to the amount by which the pressure drops below this threshold. In addition, field measurements of turbidity, in conjunction with laboratory experiments, provide evidence that ebullition is responsible for previously unexplained elevated levels of turbidity during ice-cover.

Liang Wei, Luiz Fernando Capretz

The design of recommendation systems is based on complex information processing and big data interaction. This personalized view has evolved into a hot area in the past decade, where applications might have been proved to help for solving problem in the software development field. Therefore, with the evolvement of Recommendation System in Software Engineering (RSSE), the coordination of software projects with their stakeholders is improving. This experiment examines four open source recommender systems and implemented a customized recommender engine with two industrial-oriented packages: Lenskit and Mahout. Each of the main functions was examined and issues were identified during the experiment.

Jaydeb Sarker, Asif Kamal Turzo, Amiangshu Bosu

Automated filtering of toxic conversations may help an Open-source software (OSS) community to maintain healthy interactions among the project participants. Although, several general purpose tools exist to identify toxic contents, those may incorrectly flag some words commonly used in the Software Engineering (SE) context as toxic (e.g., 'junk', 'kill', and 'dump') and vice versa. To encounter this challenge, an SE specific tool has been proposed by the CMU Strudel Lab (referred as the `STRUDEL' hereinafter) by combining the output of the Perspective API with the output from a customized version of the Stanford's Politeness detector tool. However, since STRUDEL's evaluation was very limited with only 654 SE text, its practical applicability is unclear. Therefore, this study aims to empirically evaluate the Strudel tool as well as four state-of-the-art general purpose toxicity detectors on a large scale SE dataset. On this goal, we empirically developed a rubric to manually label toxic SE interactions. Using this rubric, we manually labeled a dataset of 6,533 code review comments and 4,140 Gitter messages. The results of our analyses suggest significant degradation of all tools' performances on our datasets. Those degradations were significantly higher on our dataset of formal SE communication such as code review than on our dataset of informal communication such as Gitter messages. Two of the models from our study showed significant performance improvements during 10-fold cross validations after we retrained those on our SE datasets. Based on our manual investigations of the incorrectly classified text, we have identified several recommendations for developing an SE specific toxicity detector.

Hans van Haren, Sebastiano Piccolroaz, Marina Amadori et al.

Deep water circulation and mixing processes in deep lakes are largely unknown, although they are responsible for the transport of matter, nutrients and pollutants. Such a lack of knowledge cannot be reliably provided by numerical hydrodynamic modelling studies because detailed observations are typically not available to validate them. To overcome some of these deficiencies, a dedicated yearlong mooring comprising 100 high-resolution temperature sensors and a single current meter were located in the deeper half of the 344 m deepest point of the subalpine Lake Garda (Italy). The observations show peaks and calms of turbulent exchange, besides ubiquitous internal wave activity. In late winter, northerly winds activate episodic deep convective overturning, the dense water being subsequently advected along the lake-floor. Besides deep convection, such winds also set-up seiches and inertial waves that are associated with about 100 times larger turbulence dissipation rates than that by semidiurnal internal wave breaking observed in summer. In the lower 60 m above the lake-floor however, the average turbulence dissipation rate is approximately constant in value year-around, being about 10 times larger than open-ocean values, except during deep convection episodes.