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Robust steganography with boundary-preserving overflow alleviation and adaptive error correction

EXPERT SYSTEMS WITH APPLICATIONS 2025年 281卷

作者： Cheng, Yu Luo, Zhenlin Yin, Zhaoxia East China Normal Univ Shanghai Key Lab Multidimens Informat Proc Shanghai 200241 Peoples R China

With the rapid evolution of the Internet, the vast amount of data has created opportunities for fostering the development of steganographic techniques. However, traditional steganography faces challenges in social networks due to lossy operations such as spatial truncation during JPEG recompression, with limited research on their effects. Existing methods aim to ensure the stability of the quantized coefficients by reducing the effects of spatial truncation. Nevertheless, these approaches may induce notable alterations to image pixels, potentially compromising anti-steganalysis performance. In this study, we analyze the overflow characteristics of spatial blocks and observe that pixel values at the boundaries of spatial blocks are more prone to overflow. Based on this observation, we propose a preprocessing method that performs overflow removal operations according to the actual overflow conditions of spatial blocks, enhancing coefficient stability while minimizing modifications to spatial block boundaries, thereby ensuring image quality. Subsequently, we employ adaptive error correction coding to reduce coding redundancy, thereby augmenting robustness and mitigating its impact on anti-steganalysis performance. The experimental results indicate that the proposed method possesses a strong embedding capacity, maintaining a high level of robustness while enhancing security.

关键词： Robust steganography overflow Adaptive error correction Dither modulation Social networks

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Uncertainty Analysis of overflow Due to Sea Dike Failure During Typhoon Events

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JOURNAL OF MARINE SCIENCE AND ENGINEERING 2025年第3期13卷 573-573页

作者： Huang, Wei-Che Liu, Wen-Cheng Liu, Hong-Ming Natl United Univ Dept Civil & Disaster Prevent Engn Miaoli 360302 Taiwan

Taiwan is frequently affected by typhoons, which cause storm surges and wave impacts that damage sea dikes, resulting in overflow and subsequent flooding. Therefore, it is essential to analyze the damage to sea dikes caused by storm surges and wave impacts, leading to overflow, for effective coastal protection. This study employs the ADCIRC model coupled with the SWAN model to simulate storm surges and waves around Taiwan and develops a sea dike failure model that incorporates mechanisms for impact damage, run-up damage, and overflow calculation. To ensure model accuracy, three historical typhoon events were used for calibration and validation of the ADCIRC+SWAN model. The results show that the ADCIRC coupled with SWAN model can effectively simulate storm surges and waves during typhoons. Typhoon Soulik (2013) was simulated to examine a breach in the Tamsui Youchekou sea dike in northern Taiwan, and an uncertainty analysis was conducted using the Monte Carlo method and Bayesian theorem. The results indicate that when the compressive strength of the sea dike is reduced to 5% of its original strength, impact and run-up damage occur, leading to overflow. In the case of impact damage, the overflow volume due to the breach falls within a 95% confidence interval of 0.16 x 106 m3 to 130 x 106 m3. For run-up damage, the 95% confidence interval for the overflow volume ranges from 0.16 x 106 m3 to 639 x 106 m3. The ADCIRC+SWAN model is used to simulate storm surge and waves, incorporating impact damage and run-up damage mechanisms to represent concrete sea dike failure. This approach effectively models dike failure and calculates the resulting overflow.

关键词： uncertainty analysis sea dike failure storm surge wave overflow typhoon

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Enhancing stormwater network overflow prediction: investigation of ensemble learning models

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ACTA GEOPHYSICA 2025年第1期73卷 875-899页

作者： Boughandjioua, Samira Laouacheria, Fares Azizi, Nabiha Badji Mokhtar Annaba Univ Fac Technol Lab Soils & Hydraul POB 12 Annaba 23000 Algeria Badji Mokhtar Annaba Univ Fac Technol LABGED Lab POB 12 Annaba 23000 Algeria

This study addresses the critical issue of urban flooding caused by stormwater network overflow, necessitating unified and efficient management measures to handle increasing water volumes and the effects of climate change. The proposed approach aims to improve the precision and efficiency of overflow rate predictions by investigating advanced machine learning algorithms, specifically ensemble methods such as gradient boosting and random forest algorithms. The main contribution lies in introducing the SWN-ML approach, which integrates hydraulic simulations using MIKE + with machine learning to predict average overflow rates for various rainfall durations and return periods. Mike + model was calibrated for the only available observed data of water depth at the outlet point during the storm event of February 4, 2019. The datasets for model calibration used in ML models consisted of many input variables such as peak flow, max depth, length, slope, roughness, and diameter and average overflow rate as output variable. Experimental results show that these methods are effective under a variety of scenarios, with the ensemble methods consistently outperforming classical machine learning models. For example, the models exhibit similar performance metrics with an MSE of 0.023, RMSE of 0.15, and MAE of 0.101 for a 2-h rainfall duration and a 10-year return period. Correlation analysis further confirms the strong correlation between ensemble method predictions and MIKE + simulated models, with values ranging between 0.72 and 0.80, indicating their effectiveness in capturing stormwater network dynamics. These results validate the utility of ensemble learning models in predicting overflow rates in flood-prone urban areas. The study highlights the potential of ensemble learning models in forecasting overflow rates, offering valuable insights for the development of early warning systems and flood mitigation strategies.

关键词： Stormwater overflow Flooding Mike plus model Machine learning Ensemble learning models

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overflow in systems with two servers: the negative consequences

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FLEXIBLE SERVICES AND MANUFACTURING JOURNAL 2023年第3期35卷 838-863页

作者： Chen, Yanting Xie, Jingui Zhu, Taozeng Univ Shanghai Sci & Technol Business Sch Shanghai 200093 Peoples R China Tech Univ Munich Sch Management D-74076 Heilbronn Germany Dongbei Univ Finance & Econ Inst Supply Chain Analyt Dalian 116025 Peoples R China

We investigate a system with two types of customers wherein each customer type has a dedicated server. When the corresponding dedicated server is busy, we allow customer overflow to the non-dedicated server, and the service time of each server is customer-dependent. The objective of this study is to assess the negative consequences of overflow. On the basis of the analytical stationary distribution of the proposed two-server model, we first identify the conditions under which overflow leads to improvement of throughputs. Second, we obtain customers' overflow rates and ratios. For a symmetric system under heavy traffic, the wrong assignment ratio comes close to 50%. Third, we analyze the probability that a customer is served by a non-dedicated server. The probability that both servers are serving non-dedicated customers approaches 25% in a symmetric system under heavy traffic. Finally, we determine various overflow conditions while including the overflow costs.

关键词： overflow Customer-dependent service time Negative consequences

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overflow and loss probabilities in a finite ATM buffer fed by self-similar traffic

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QUEUEING SYSTEMS 1999年第1-3期32卷 233-256页

作者： Tsybakov, B Georganas, ND Qualcomm Inc San Diego CA 92121 USA Univ Ottawa Sch Informat Technol & Engn Multimedia Commun Res Lab Ottawa ON K1N 6N5 Canada

In [13], real-time measurements from LANs, variable-bit-rate video sources, ISDN control-channels, the World Wide Web and other communication systems have shown that traffic exhibits a behaviour of self-similar nature. In this paper, we give new lower bounds to buffer-overflow and cell-loss probabilities for an ATM queue system with a self-similar cell input traffic and finite buffer. The bounds are better than those obtained in [20], in an important region of parameters. As in [20], they decay hyperbolically with buffer size, when the latter goes to infinity. However, in some region, a factor which accompanies the decay is higher in this paper than in [20].

关键词： buffer overflow loss probabilities ATM self-similar traffic

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overflow-assisted laser machining of titanium alloy: surface characteristics and temperature field modeling

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INTERNATIONAL JOURNAL OF ADVANCED MANUFACTURING TECHNOLOGY 2017年第1-4期88卷 147-158页

作者： Tangwarodomnukun, Viboon King Mongkuts Univ Technol Thonburi Dept Prod Engn Fac Engn Bangkok 10140 Thailand

Underwater laser machining process is a promising method to cut materials with less thermal damage. A variation of underwater technique is overflow-assisted laser ablation. This process can introduce a higher thermal convection and more uniform water layer than the typical underwater method. Such characteristics can encourage the damage-free fabrication and also stabilize the laser ablation in water. In this study, cut profile and temperature distribution of workpiece induced by the overflow technique were investigated. Titanium alloy (Ti-6Al-4V) used as a work sample was grooved by a nanosecond pulse laser under different overflow conditions. The effects of laser power, laser repetition rate, and water flow velocity were experimentally and numerically examined. A clean and smooth cut surface can be fabricated when the overflow technique was used. Microcracks and porosities found on the laser-ablated area were also addressed in this study. The temperature field of titanium alloy under the different ablation conditions was simulated by using the finite difference computation. The transient heat conduction model was implemented together with the enthalpy method and temperature-dependent material properties. By using the developed model, the groove depths obtained from the experiment and simulation were in a good agreement.

关键词： Laser Water overflow Ablation Modeling Titanium

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overflow risk analysis for stormwater quality control basins

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JOURNAL OF HYDROLOGIC ENGINEERING 2002年第6期7卷 428-434页

作者： Guo, JCY Univ Colorado Dept Civil Engn Denver CO 80217 USA

The operational cycle of a stormwater quality control basin can be divided into the waiting period between events and the filling and draining period during an event. In this study, an inherent overflow risk is defined as the probability of having a large event exceed the basin storage capacity. Such a probability is prescribed by the basin storage capacity and the local distribution of rainfall event depths. An operational overflow risk is defined as the probability of having the basin overwhelmed by a subsequent storm event during the draining process. An operational risk is found to be dependent on watershed runoff coefficient, basin drain time, local average rainfall event depth, and average rainfall interevent time. In practice, the selection of a basin drain time is a tradeoff between the removal of suspended solids in stormwater and the overflow risk. The concept of "the longer, the better" applies to the sedimentation process, but concern for the overflow risk requires that the basin drain as fast as possible. This paper presents a design method by which the overflow risk associated with a basin storage volume can be evaluated for various drain times. The mathematical models developed to describe the distribution of rainfall interevent time and the runoff capture curve provide good agreement with the long-term continuous rainfall data recorded in seven metropolitan areas in the United States. The risk-based approach developed in this study provides a quantifiable basis for making the decision on the operation of a stormwater quality control basin.

关键词： overflow stormwater water quality risk analysis urban areas

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overflow handling in inner-product processors

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IEEE TRANSACTIONS ON CIRCUITS AND SYSTEMS II-EXPRESS BRIEFS 2000年第10期47卷 1086-1090页

作者： Elguibaly, F Univ Victoria Dept Elect & Comp Engn Victoria BC V8W 3P6 Canada

In complemented-coded arithmetic, overflow can occur and the final result could be incorrect;We present in this brief an extended precision technique to carry out chained additions without error using a datapath whose width is minimum, dictated only by the required precision, not the prevention of overflow. The technique is based on the use of an up/down counter that is controlled by overflow conditions after each add operation. The proposed technique is superior to traditional approaches of controlling overflow since it does not require extending the width of the datapath or limiting the dynamic range of data. We illustrate how the technique is used in three hardware structures that perform the inner-product operation.

关键词： Baugh-Wooley multiplication carry-save addition carry-save multiplication inner-product multiply-accumulate overflow two's-complement arithmetic

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overflow warning and remote monitoring technology based on improved random forest

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NEURAL COMPUTING & APPLICATIONS 2021年第9期33卷 4027-4040页

作者： Liang, Haibo Han, Haochen Ni, Pengbo Jiang, Yingjun Southwest Petr Univ Sch Mech Engn Chengdu 610500 Peoples R China China France Bohai Geoserv Co Ltd Tianjin 300457 Peoples R China CNPC Chuanqing Drilling Engn Technol Res Inst Deyang 618300 Peoples R China

overflow accident is one of the accidents with the greatest impact on safe drilling. An unclear diagnosis of an overflow accident or improper post-processing may cause serious drilling accidents. Based on this, a remote monitoring platform for overflow accidents is proposed. The diagnosis method of overflow accidents was researched and optimized, and a random forest overflow accident identification and classification model based on bat algorithm optimization was established. This model can optimize the optimal parameter combination and has the ability to handle a large number of eigenvalues. Through comparative analysis, the optimization model has higher accuracy, and the accuracy rate is increased by 6.67%.

关键词： overflow Remote monitoring Bat algorithm Random forest Early warning

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overflow characteristics of circular-crested weirs

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JOURNAL OF HYDRAULIC RESEARCH 2012年第2期50卷 241-242页

作者： Castro-Orgaz, Oscar CSIC Inst Agr Sostenible E-14080 Cordoba Spain

Journal of Hydraulic Research overflow characteristics of circular-crested weirs By SARA BAGHERI and MANOUCHEHR HEIDARPOUR, Journal of Hydraulic Research, Vol. 48, No. 4 (2010), pp. 515-520

关键词： equipotentials scale effect velocity distribution Writers discharge coefficient Weirs weir flow overflow

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