Comparison of the robustness-based optimal designs of water distribution systems in three different formulations

Jung, Donghwi,Kang, Doosun,Chung, Gunhui,Kim, Joong Hoon IWA Publishing 2013 Journal of hydroinformatics Vol.15 No.4

<P>Robustness is generally defined as a system's ability to stay within satisfactory bounds against variations in system factors. Recently, robustness has been indicated to be a useful objective function for the optimal design of water distribution systems (WDSs). While various formulations are possible to represent WDS robustness, few efforts have been made to compare the performances of these formulations. This study examined three potential formulations for quantifying system robustness to provide guidelines on the usage of a robustness index. Giustolisi <I>et al</I>.'s robustness index (see Giustolisi <I>et al.</I> (2009) ‘Deterministic versus stochastic design of water distribution networks’, <I>J. Water Resour. Plann. Manage.</I> <B>135</B> (2), 117–127) was adopted to calculate nodal robustness, while the system robustness was defined using three different formulations: (1) minimum among nodal robustness values; (2) total sum of nodal robustness; and (3) sum of nodal robustness at multiple critical nodes. The three proposed formulations were compared through application to identify the most appropriate one for enhancing system robustness in general; three representative benchmark networks were optimally designed to minimize the economic cost while maximizing the system robustness.</P>

Robustness Management with Data Quality in Information Systems

Zhiting Song,Yanming Sun 보안공학연구지원센터 2016 International Journal of Hybrid Information Techno Vol.9 No.9

The data quality in information systems affects system robustness significantly. Although a large body of research focuses on the issue of data quality, seldom has literature been done to develop effective control policies to manage system robustness associated with data errors. A process-oriented methodology is proposed to manage system robustness measured by performance, control cost and control time, which is achieved through establishing formal model of information systems and mathematical optimization models of system robustness. The proposed methodology captures how structural and functional characteristics of tasks affect system robustness and finds the optimal control policies, which facilitates the robustness-based design and management of information systems respectively. The methodology is illustrated in the case study.

A Quantitative Method for Seismic Robustness of RC Frame Considering Resistance Vulnerability of Column and Storey Drift Ratios

Guohua Sheng,Shengji Jin,Lintao Ma,Quan Bai,Chao Xu,Xiaoyu Wang 대한토목학회 2024 KSCE Journal of Civil Engineering Vol.28 No.1

The concept of seismic robustness is proposed by combining the concept of seismic performance and structural robustness. The existing qualitative, quantitative and evaluation methods of seismic robustness are all direct researched on the whole structure, and the influence mechanism of its internal components on the overall seismic robustness is still unclear. It is very important to establish a clear relationship between component design and structural seismic robustness for the structural design, reinforcement design and final evaluation of structural seismic robustness. Based on this, taking the column as the starting point, a quantitative method for the seismic robustness of RC frame by the seismic robustness index is proposed, which takes into account the resistance vulnerability of column and influence of column on the storey drift ratios (SDRs). In which, the resistance vulnerability is represented by the defined control vulnerability coefficient Pimax, and the influence on the SDRs are represented by the storey drift ratio importance coefficients (SDRCs) . The method not only reflects the essential mechanical properties of the column, but also reflects the effects brought about by different SALs. The feasibility of the method is demonstrated by numerical examples of two types of failures (assuming single column and two columns failure), and four optimization design proposals are proposed for it. The analysis shows that  of the target columns to the floor where the target columns located are obviously greater than those on the remaining floors of the target frame. The seismic robustness index R decreases sharply with the increase of the seismic action level (SAL). R is different compare single column failure with two columns failure under 4 SALs. The most effective way to improve the R of the frame under a certain SAL is to retrofit its control column.

악성코드 변종 분석을 위한 AI 모델의 Robust 수준 측정 및 개선 연구

이은규,정시온,이현우,이태진 한국정보보호학회 2022 정보보호학회논문지 Vol.32 No.5

Today, AI(Artificial Intelligence) technology is being extensively researched in various fields, including the field of malware detection. To introduce AI systems into roles that protect important decisions and resources, it must be a reliable AI model. AI model that dependent on training dataset should be verified to be robust against new attacks. Rather than generating new malware detection, attackers find malware detection that succeed in attacking by mass-producing strains of previously detected malware detection. Most of the attacks, such as adversarial attacks, that lead to misclassification of AI models, are made by slightly modifying past attacks. Robust models that can be defended against these variants is needed, and the Robustness level of the model cannot be evaluated with accuracy and recall, which are widely used as AI evaluation indicators. In this paper, we experiment a framework to evaluate robustness level by generating an adversarial sample based on one of the adversarial attacks, C&W attack, and to improve robustness level through adversarial training. Through experiments based on malware dataset in this study, the limitations and possibilities of the proposed method in the field of malware detection were confirmed. 오늘날 AI(Artificial Intelligence) 기술은 악성코드 분야를 비롯하여 다양한 분야에서 광범위하게 연구되고 있다. 중요한 의사결정 및 자원을 보호하는 역할에 AI 시스템을 도입하기 위해서는 신뢰할 수 있는 AI 모델이어야 한다. 학습 데이터셋에 의존적인 AI 모델은 새로운 공격에 대해서도 견고한지 확인이 필요하다. 공격자는 악성코드를 새로 생성하기보단, 기존에 탐지되었던 악성코드의 변종을 대량 생산하여 공격에 성공하는 악성코드를 탐색다. AI 모델의 Misclassification을 유도하는 Adversarial attack과 같이 대부분의 공격은 기존 공격에 약간에 변형을 가해 만든 공격들이다. 이러한 변종에도 대응 가능한 Robust한 모델이 필요하며, AI 평가지표로 많이 사용되는 Accuracy, Recall 등으로는 모델의 Robustness 수준을 측정할 수 없다. 본 논문에서는 Adversarial attack 중 하나인 C&W attack을 기반으로 Adversarial sample을 생성하여 Robustness 수준을 측정하고 Adversarial training 을 통해 Robustness 수준을 개선하는 방법을 실험한다. 본 연구의 악성코드 데이터셋 기반 실험을 통해 악성코드 분야에서 해당 제안 방법의 한계 및 가능성을 확인하였다.

공급사슬에서의 리스크 대응 활동과 강건성 및 공급사슬성과 간의 관계에 대한 연구

박찬권(Park, Chan-Kwon),박성민(Park, Sung-Min) 한국물류학회 2021 물류학회지 Vol.31 No.3

본 연구는 공급사슬 네트워크에서 발생할 수 있는 리스크 요인들을 구분하고 이들 리스크 요인에 대하여 적절하게 대응하는활동이 리스크 발생 상황에서 공급사슬 회복탄력성의 일환인 강건성 역량으로 연결될 수 있으며, 이러한 강건성 역량이 궁극적으로 공급사슬성과로 나타날 수 있는가에 대하여 확인하는 것이다. 이러한 연구 목표를 달성하기 위하여 우리나라 제조기업체들 중108개 업체의 설문지를 연구에 활용하였으며, 2차에 걸쳐서 연구항목별로 신뢰성과 타당성을 확인하고 경로분석 방식으로 연구를진행하였다. 연구가설 검정 결과를 살펴보면 먼저 운송리스크 대응, 재고리스크 대응, 정보리스크 대응, 공급자리스크 대응은 강건성에 유의한 정(+)의 영향을 미친다. 그러나 시장리스크 대응은 강건성에 부(-)의 영향을 미치지만 유의하지는 않았으며, 예측리스크 대응은 강건성에 정(+)의 영향을 미치지만 유의하지는 않았다. 마지막으로 강건성은 공급사슬성과에 유의한 정(+)의 영향을 미치는 것으로 검정되었다. 또한 공급사슬 리스크 대응과 공급사슬성과 사이에서 강건성의 매개효과를 분석한 결과 강건성은 매개변수의 역할을 하는 것으로 검정 되었다. 따라서 리스크 대응 활동과 공급사슬 회복탄력성으로써 강건성, 공급사슬성과 간의 전체적인 관계구조에 대하여 실증하였다. This study categorizes risk factors that may occur in supply chain networks, and activities that respond appropriately to these risk factors can be linked to robustness capabilities as a part of supply chain resilience in the event of a risk. As a result, it is to check whether it can appear as a performance in the supply chain. In order to achieve this research goal, questionnaires of 108 manufacturers among Korean manufacturing companies were used for the study, and the reliability and validity of each study item were checked in the second phase, and the study was conducted in a path analysis method. Looking at the research hypothesis test results, first, transport risk response, inventory risk response, information risk response, and supplier risk response have a significant positive (+) effect on robustness. However, over-market risk response had a negative (-) effect on robustness, but not significant, while predictive risk response had a positive (+) effect on robustness, but not significant. Finally, robustness was tested to have a significant positive (+) effect on supply chain performance. Also, as a result of analyzing the mediating effect of robustness between supply chain risk response and supply chain performance, it was verified that robustness plays a role as a parameter. Therefore, the overall relationship structure between robustness and supply chain performance as risk response activities and supply chain resilience was demonstrated.

Robustness-Improvement Strategy and Modeling under Uncertainty of Chinese Catering Service Supply Chain

Juanqiong Gou,Jing Xiang,Shujun Zhang,Wei Dai 보안공학연구지원센터 2015 International Journal of u- and e- Service, Scienc Vol.8 No.7

Catering Service Supply Chain (CSSC) is a new supply chain, of which Catering Service Integrator (CSI) is in the center accompany with Functional Catering Service Provider (FCSP). The core objective of CSSC is to provide different catering enterprises with supply chain services. Instability, non-standardization, specialty and diversity characteristics of the Chinese catering industry inevitably lead to demand uncertainty of CSSC, directly resulting in the uncertainty of operation and supply side. The uncertainty of supply chain system is the basis of robust optimization study, under the influence of uncertainty, robustness is extremely important to ensure stable income and continuous operation of supply chain. This research classifies various uncertainty scenarios, based on robust optimization method. Two strategies, service coordination with widely knowledge sharing, and synchronous decision with intelligent inducement, are designed to induce and integrate personalized demand to get the scale effect and the coordination of the entire supply chain. From a point of quantitative view, this research builds up robust optimization model to improve robustness of CSSC, deposing the target into two coordinated parts. The coordination is of great sense, including two objectives simultaneously, the first one aims to maximize the delivery rate of order demand, the second one aims to optimize profit of CSI and FCSP. According to data examination, the coordinative strategies and robust optimization model can effectively control the uncertainty of the whole supply chain, and then improve the robustness of CSSC.

Robustness Analysis of a Flexible Cable-Strut Tensile Structure

Lian-meng Chen,Wei-feng Gao,Zhichao Jiang,Yi-yi Zhou,Fu-bo Zhang,Shi-lin Dong 한국강구조학회 2020 International Journal of Steel Structures Vol.20 No.5

Currently, the robustness analysis of structure is primarily related to rigid structures, and little has been done to study the robustness of spatial fl exible cable-strut tensile structures with larger span, more complex forms, lower redundancy, more sensitivity to unexpected interference such as construction deviations, etc. Based on the H ∞ theory, this paper starts with the fundamental theory and develops analysis method for the robustness of fl exible cable-strut tensile structures, and then the relationships between the structural robustness and some design parameters such as initial pre-stress level, load distribution form, structural span, cross-section area, rise-span ratio, etc. are analysed through a case study of a concrete cable-strut tensile structure in China. On this basis, the eff ects of construction errors such as element-length error and supporting node position error are further analysed. Finally, the importance of each kind of element is analysed by means of conceptual removal of element. The results show that the higher the initial pre-stress level, the larger the element cross-section, the smaller the structural span, the larger the rise-span ratio and the more uniform the load distribution, the stronger the structural robustness. In the limited construction error range, the element-length error and the supporting node position error have little eff ects on the robustness of the structure. The hoop cables are the more important elements and the elements in inner region of the structure are of comparatively lower importance in the cable dome structure in this study.

Network Robustness of Major Asian Airlines and the Impact of Airports’ Brokerage Roles

권오경,이수비,정혜민,프렘 체트리,한옥순 인하대학교 정석물류통상연구원 2019 JOURNAL OF INTERNATIONAL LOGISTICS AND TRADE Vol.17 No.4

This study aims to evaluate the network robustness of major Asian airlines and to explore which airport types have the greatest impact on robustness. We also analyze airports’ specific brokerage roles and their impacts on the robustness of the entire air route network. We select 10 major Asian full-service airlines that operate the main passenger terminals at the top-ranked hub airports in Asia. Data is collected from the Official Airline Guide passenger route dataset for 2017. The results of the network robustness analysis show that Air China and China Eastern Airlines have relatively high network robustness. In contrast, airlines with broader international coverage, such as Japan Airlines, Korean Air, and Singapore Airlines have higher network vulnerability. The measure of betweenness centrality has a greater impact on the robustness of air route networks than other centrality measures have. Furthermore, the brokerage role analysis shows that Chinese airports are more influential within China and Asia but are less influential globally when compared to other major hub airports in Asia. Incheon International Airport, Singapore Changi Airport, Hong Kong International Airport, and Narita International Airport play strong “liaison” roles. Among the brokerage roles, the liaison role has a greater impact on the robustness of air route networks.

Network Robustness of Major Asian Airlines and the Impact of Airports’ Brokerage Roles

Oh Kyoung Kwon,Soobi Lee,Hye Min Chung,Prem Chhetri,Ok Soon Han 인하대학교 정석물류통상연구원 2019 JOURNAL OF INTERNATIONAL LOGISTICS AND TRADE Vol.17 No.4

This study aims to evaluate the network robustness of major Asian airlines and to explore which airport types have the greatest impact on robustness. We also analyze airports’ specific brokerage roles and their impacts on the robustness of the entire air route network. We select 10 major Asian full-service airlines that operate the main passenger terminals at the top-ranked hub airports in Asia. Data is collected from the Official Airline Guide passenger route dataset for 2017. The results of the network robustness analysis show that Air China and China Eastern Airlines have relatively high network robustness. In contrast, airlines with broader international coverage, such as Japan Airlines, Korean Air, and Singapore Airlines have higher network vulnerability. The measure of betweenness centrality has a greater impact on the robustness of air route networks than other centrality measures have. Furthermore, the brokerage role analysis shows that Chinese airports are more influential within China and Asia but are less influential globally when compared to other major hub airports in Asia. Incheon International Airport, Singapore Changi Airport, Hong Kong International Airport, and Narita International Airport play strong “liaison” roles. Among the brokerage roles, the liaison role has a greater impact on the robustness of air route networks.

Structural robustness: A revisit

João André 국제구조공학회 2020 Structural Engineering and Mechanics, An Int'l Jou Vol.76 No.2

The growing need for assuring efficient and sustainable investments in civil engineering structures has determined a renovated interest in the rational design of such structures from designers, clients and authorities. As a result, risk-informed decision-making methodologies are increasingly being used as a direct decision tool or as an upper-level layer from which performance-based approaches are then calibrated against. One of the most important and challenging aspects of today’s structural design is to adequately handle the system-level effects, the known unknowns and the unknown unknowns. These aspects revolve around assessing and evaluating relevant damage scenarios, namely those involving unacceptable/intolerable damage levels. Hence, the importance of risk analysis of disproportionate collapse, and along with it of robustness. However, the way robustness has been used in modern design codes varies substantially, from simple provisions of prescriptive rules to complex risk analysis of the disproportionate collapse. As a result, implementing design for robustness is still very much a grey area and more so when it comes to defining means to quantify robustness. This paper revisits the most common robustness frameworks, highlighting their merits and limitations, and identifies one among them which is very promising as a way forward to solve the still open challenges.