• Title/Summary/Keyword: Meta modeling

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Neoadjuvant chemoradiotherapy versus immediate surgery for resectable and borderline resectable pancreatic cancer: Meta-analysis and trial sequential analysis of randomized controlled trials

  • Shahab Hajibandeh;Shahin Hajibandeh;Christina Intrator;Karim Hassan;Mantej Sehmbhi;Jigar Shah;Eshan Mazumdar;Ambareen Kausar;Thomas Satyadas
    • Annals of Hepato-Biliary-Pancreatic Surgery
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    • v.27 no.1
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    • pp.28-39
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    • 2023
  • We aimed to compare resection and survival outcomes of neoadjuvant chemoradiotherapy (CRT) and immediate surgery in patients with resectable pancreatic cancer (RPC) or borderline resectable pancreatic cancer (BRPC). In compliance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses statement standards, a systematic review of randomized controlled trials (RCTs) was conducted. Random effects modeling was applied to calculate pooled outcome data. Likelihood of type 1 or 2 errors in the meta-analysis model was assessed by trial sequential analysis. A total of 400 patients from four RCTs were included. When RPC and BRPC were analyzed together, neoadjuvant CRT resulted in a higher R0 resection rate (risk ratio [RR]: 1.55, p = 0.004), longer overall survival (mean difference [MD]: 3.75 years, p = 0.009) but lower overall resection rate (RR: 0.83, p = 0.008) compared with immediate surgery. When RPC and BRPC were analyzed separately, neoadjuvant CRT improved R0 resection rate (RR: 3.72, p = 0.004) and overall survival (MD: 6.64, p = 0.004) of patients with BRPC. However, it did not improve R0 resection rate (RR: 1.18, p = 0.13) or overall survival (MD: 0.94, p = 0.57) of patients with RPC. Neoadjuvant CRT might be beneficial for patients with BRPC, but not for patients with RPC. Nevertheless, the best available evidence does not include contemporary chemotherapy regimens. Patients with RPC and those with BRPC should not be combined in the same cohort in future studies.

A meta analysis of the climate change impact on rice yield in South Korea (기후변화가 국내 쌀 생산량에 미치는 영향에 대한 메타분석)

  • Shin, Deok Ha;Lee, Mun Su;Park, Ju-Hyun;Lee, Yung-Seop
    • Journal of the Korean Data and Information Science Society
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    • v.26 no.2
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    • pp.355-365
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    • 2015
  • As the global climate has dramatically changed over the past decades, there has been active research on evaluating its effects on food security, which has been recognized as one of the most important issues in the field. In this study, we analyzed the impact of the climate change on the Korean agriculture using meta-analysis methods. Especially, our research focus is on estimating the effect of CO2 concentration and two adaptations (planting-date and cultivar adjustments)on rice that accounts for a larger proportion of the Korean domestic agriculture. Unlike traditional general meta-analysis methods that use summary statistics of effects of interest, meta analysis specific to the agriculture literature was conducted by integrating the data on rice yield that were generated under various CO2 emission scenarios and general circulating models of the 6 collected individual studies. As a modeling approach, the rice yield change ratio was set as the dependent variable and the main and interaction effects of CO2 concentration and adaptation were considered as independent variables in a regression model, As a result, CO2 is estimated to have opposite effects on rice yield depending on whether any of the two adaptations is applied or not; decreasing effect without adaptation and increasing effect with adaptation. In addition, it turns out that the cultivar adjustment has a higher increasing effect on rice yield than the planting-date adjustment. The results of the study are expected to be used as basic quantitative data for establishing responsive polices to the future climate changes.

Discovering Interdisciplinary Convergence Technologies Using Content Analysis Technique Based on Topic Modeling (토픽 모델링 기반 내용 분석을 통한 학제 간 융합기술 도출 방법)

  • Jeong, Do-Heon;Joo, Hwang-Soo
    • Journal of the Korean Society for information Management
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    • v.35 no.3
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    • pp.77-100
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    • 2018
  • The objectives of this study is to present a discovering process of interdisciplinary convergence technology using text mining of big data. For the convergence research of biotechnology(BT) and information communications technology (ICT), the following processes were performed. (1) Collecting sufficient meta data of research articles based on BT terminology list. (2) Generating intellectual structure of emerging technologies by using a Pathfinder network scaling algorithm. (3) Analyzing contents with topic modeling. Next three steps were also used to derive items of BT-ICT convergence technology. (4) Expanding BT terminology list into superior concepts of technology to obtain ICT-related information from BT. (5) Automatically collecting meta data of research articles of two fields by using OpenAPI service. (6) Analyzing contents of BT-ICT topic models. Our study proclaims the following findings. Firstly, terminology list can be an important knowledge base for discovering convergence technologies. Secondly, the analysis of a large quantity of literature requires text mining that facilitates the analysis by reducing the dimension of the data. The methodology we suggest here to process and analyze data is efficient to discover technologies with high possibility of interdisciplinary convergence.

The Economic Impact of Contaminated and Noxious Sites : A Meta Analysis (오염-유해시설의 경제적 영향 : 메타분석)

  • Won, Doo Hwan
    • Environmental and Resource Economics Review
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    • v.17 no.1
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    • pp.165-196
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    • 2008
  • This paper reports a quantitative meta analysis of the economic impacts of localized noxious and contaminated sites. Using either hedonic property value or stated preference methods, economists have studied the effects of contamination or noxious activities, or the benefits realized from their elimination, on real estate prices at more than 40 sites. In support of wise public and private investments in environmental quality, most of these studies aim to inform decision makers about the benefits of remediation and cleanup. Their results vary considerably, but there has been no previous systematic effort to analyze the differences and identify shared insights. This study uses established methods of meta analysis to identify points of agreement and differences in this body of literature. The studies are characterized by the type of site, modeling approach, geographic extent of impacts, data features, and other key factors that underlie their value estimates. The impact estimates are normalized as proportional effects on property values. This study attempts to discover whether the estimated economic impacts of contamination or noxious activity differ according to these characteristics of the studies, and whether anything general can be said about the economic consequences of site contamination and remediation. Bivariate, multivariate, and logit techniques are applied to the data. The results suggest that the property value is the most sensitive to water base contamination, published case studies result in systematically greater environmental value than those in unpublished reports, and real estate markets show responses to environmental condition changes.

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A Load-Balancing Approach Using an Improved Simulated Annealing Algorithm

  • Hanine, Mohamed;Benlahmar, El-Habib
    • Journal of Information Processing Systems
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    • v.16 no.1
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    • pp.132-144
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    • 2020
  • Cloud computing is an emerging technology based on the concept of enabling data access from anywhere, at any time, from any platform. The exponential growth of cloud users has resulted in the emergence of multiple issues, such as the workload imbalance between the virtual machines (VMs) of data centers in a cloud environment greatly impacting its overall performance. Our axis of research is the load balancing of a data center's VMs. It aims at reducing the degree of a load's imbalance between those VMs so that a better resource utilization will be provided, thus ensuring a greater quality of service. Our article focuses on two phases to balance the workload between the VMs. The first step will be the determination of the threshold of each VM before it can be considered overloaded. The second step will be a task allocation to the VMs by relying on an improved and faster version of the meta-heuristic "simulated annealing (SA)". We mainly focused on the acceptance probability of the SA, as, by modifying the content of the acceptance probability, we could ensure that the SA was able to offer a smart task distribution between the VMs in fewer loops than a classical usage of the SA.

A Study About Verification Model for Cooperation of Software Components of AUML Base (AUML기반의 소프트웨어 컴포넌트들의 협력성을 위한 검증 모텔에 관한 연구)

  • Gawn, Han-Hyoun;Park, Jae-Bock
    • Journal of the Korea Computer Industry Society
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    • v.6 no.3
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    • pp.529-538
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    • 2005
  • AUML (Agent Unified Modeling Language) is specification anger of agent software system, sight anger, language that do creation by purpose. Do so that may apply Together that is one of automation application program creation system to Agent's BDI in trend sophistication of software, large size Tuesday in this research and investigate this about operation between component system. Standard detailed statement (FIPA:Foundation for Inteligent Physical Agent) that use can consist by data exchange between component and cooperate each other even if type of component is different mutually to base ACL message, and protocole use and study about method and accuracy and consistency that minimize error when embody this using meta model base etc.. through object intention modelling.

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A Construction of the C_MDR(Component_MetaData Registry) for the Environment of Exchanging the Component (컴포넌트 유통환경을 위한 컴포넌트 메타데이타 레지스트리 구축 : C_MDR)

  • Song, Chee-Yang;Yim, Sung-Bin;Baik, Doo-Kwon;Kim, Chul-Hong
    • Journal of KIISE:Computing Practices and Letters
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    • v.7 no.6
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    • pp.614-629
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    • 2001
  • As the information-intensive society in 21c based on the environment of global internet is promoted, the software is getting more large and complex, and the demand for the software is increasing briskly. So, it becomes an important issue in academic and industrial field to activate reuse by developing and exchanging the standardized component. Currently, the information services as a product type of each company are provided in foreign market place for reusing a commercial component, but the components which are serviced in each market place are different, insufficient and unstandardized. That is, construction for Component Data Registry based on ISO 11179, is not accomplished. Hence, the national government has stepped up the plan for sending out public component at 2001. Therefore, the systems as a tool for sharing and exchange of data, have to support the meta-information of standardized component. In this paper, we will propose the C_MDR system: a tool to register and manage the standardized meta-information, based upon ISO 11179, for the commercialized common component. The purpose of this system is to systemically share and exchange the data in chain of acceleration of reusing the component. So, we will show the platform of specification for the component meta-information, then define the meta-information according to this platform, also represent the meta-information using XML for enhancing the interoperability of information with other system. Moreover, we will show that three-layered expression make modeling to be simple and understandable. The implementation of this system is to construct a prototype system of the component meta-information through the internet on www, this system uses ASP as a development language and RDBMS Oracle for PC. Thus, we may expect the standardization of the exchanged component metadata, and be able to apply to the exchanged reuse tool.

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Analysis of the Front Disk Brake Squeal Using Kriging Method (크리깅기법을 이용한 전륜 디스크 브레이크 모델의 스퀼 저감 해석)

  • Sim, Hyun-Jin;Park, Sang-Gil;Kim, Heung-Seob;Oh, Jae-Eung
    • Transactions of the Korean Society for Noise and Vibration Engineering
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    • v.18 no.10
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    • pp.1042-1048
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    • 2008
  • Disc brake noise is an important customer satisfaction and warranty issue for many manufacturers as indicated by technical literature regarding the subject coming from Motor Company. This research describes results of a study to assess disk brake squeal propensity using finite element methods and optimal technique (Kriging). In this study, finite element analysis has been performed to determine likely modes of brake squeal. This paper deals with friction-induced vibration of disc brake system under contact friction coefficient. A linear, finite element model to represent the floating caliper disc brake system is proposed. The complex eigen-values are used to investigate the dynamic stability and in order to verify simulations which are based on the FEM model. In this paper, Kriging from among the meta-modeling techniques is proposed for an optimal design scheme to reduce the brake squeal noise.

Evaluation of Optimization Models for a Dimpled Channel to Enhance Heat Transfer (딤플 유로의 열전달 증진을 위한 최적화모델 비교)

  • Shin, Dong-Yoon;Kim, Kwang-Yong;Samad, Abdus
    • Proceedings of the KSME Conference
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    • 2007.05b
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    • pp.2552-2557
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    • 2007
  • Shape optimization of an internal cooling passage with staggered dimples on single surface is performed and performances of surrogates are evaluated in this paper. Optimizations are performed so that turbulent heat transfer can be enhanced compromising with pressure loss due to friction. The three-dimensional governing differential equations have been solved to find the overall Nusselt number and friction factor which are related to the objective functions of this problem. Three design variables were selected among the dimensionless geometric variables. Basic surrogate models such as second order polynomial response surface approximation (RSA), Kriging meta-modeling technique, radial basis neural network (RBNN), and derived press based averaged (PBA) surrogate model are constructed. The optimal points are searched from the above constructed surrogates by sequential quadratic programming (SQP). It is shown that use of multiple surrogates can increase the robustness in prediction of better design with minimum computational cost.

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A Situation-Based Dialogue Management with Dialogue Examples (대화 예제를 이용한 상황 기반 대화 관리 시스템)

  • Lee, Cheong-Jae;Jung, Sang-Keun;Lee, Geun-Bae
    • MALSORI
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    • no.56
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    • pp.185-194
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    • 2005
  • In this paper, we present POSSDM (POSTECH Situation-Based Dialogue Manager) for a spoken dialogue system using a new example and situation-based dialogue management technique for effective generation of appropriate system responses. Spoken dialogue system should generate cooperative responses to smoothly control dialogue flow with the users. We introduce a new dialogue management technique incorporating dialogue examples and situation-based rules for EPG (Electronic Program Guide) domain. For the system response inference, we automatically construct and index a dialogue example database from dialogue corpus, and the best dialogue example is retrieved for a proper system response with the query from a dialogue situation including a current user utterance, dialogue act, and discourse history. When dialogue corpus is not enough to cover the domain, we also apply manually constructed situation-based rules mainly for meta-level dialogue management.

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