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히트펌프 및 태양광 시스템의 연합 냉방 제어
No full text학위논문(석사) -- 서울대학교대학원 : 공과대학 건축학과, 2024. 2. Cheol-Soo Park.The building industry is currently shifting towards achieving net-zero buildings, encouraging the integration of heat pumps (HP) and sustainable power sources, such as photovoltaic (PV) systems, to utilize locally generated renewable energy for heating and cooling. However, the existing approach to HP control, treating it as a local control problem, is based on local state information and may overlook interconnected dynamic behavior within a building, thereby failing to harness the energy-saving potential of the system fully. In this study, the authors proposed a federated control approach capable of considering dynamic relationships among the outdoor environment, indoor thermal zone, and HP systems assisted by PV systems. This thesis presents a real-life implementation of online federated control in an office building in Goyang, Seoul. For this purpose, three Artificial Neural Networks (ANN) were developed to predict the thermal zones temperature, the HP's energy consumption, and the PV's electricity. The input and output variables of the ANNs were structured in a federated manner to accurately simulate the interactions in thermal and electrical behaviors of the target building. Using the model predictive control (MPC) framework, the real-time federated cooling control was successfully implemented over seven days (September 1, 2023- September 7, 2023), determining HP control variables (supply airflow rate, setpoint temperature). Compared to the local control that relies on room air temperature only, the federated approach achieved a median 53.2% reduction in net energy consumption. This improvement can be attributed to the federated control's ability to predict room air changes, forecast PV energy generation, comprehend HP energy use (including part-load and COP), and understand the interconnected dynamics between thermal zones, HP, and PV systems. This study emphasizes the importance of incorporating dynamic interactions between systems when formulating control strategies and recognizing the stochastic variation in the effectiveness of federated control.건물 설비 시스템 분야에서는 히트펌프와 태양광 발전 시스템의 통합 설비 구축을 통해 건물에서 생산된 재생 에너지를 난방 및 냉방에 활용하는 시도가 진행되고 있다. 그러나, 대다수의 기존 건물 환경 설비 시스템은 주로 상태 정보(예: 현재 실 온도)만을 기준으로 제어(local control)를 수행한다. 이는 건물 시스템의 동적 상호작용(예: 室의 열적 거동, 히트 펌프, 태양광 발전 등)을 고려하지 못하여, 건물 운영 시 최적의 에너지 효율을 달성하는 데 한계가 있다. 그러나, 연합 제어(federated control)는 관련된 동적 시스템의 상호 작용을 고려할 수 있으므로, 에너지 및 실내 환경 측면에서 기존 제어보다 우수하다고 알려져 있다.
본 연구에서는 실내외 열적 거동, 히트 펌프 (heat pump)와 태양광 설비(photovoltaic) 간의 비선형 동특성을 고려할 수 있는 연합 제어 접근 방식을 제안하고, 해당 설비가 설치된 사무용 건물을 대상으로 연합 냉방 제어를 수행하였다. 이를 위해, 대상 건물에서 실외 및 실내 환경 정보 및 히트펌프와 태양광 발전 시스템 운영 데이터를 수집하였다. 그리고, 향후 30분 간의 (1) 실내 온도, (2) 히트펌프의 전력 사용량, (3) 태양광 패널의 전력 발전량을 예측할 수 있는 3개의 인공신경망(Artificial Neural Network, ANN) 시뮬레이션 모델을 개발하고, Model Predictive Control (MPC)을 구현하였다. 시스템 간의 상호작용을 반영한 신뢰성 높은 시뮬레이션을 위해, ANN은 입출력 변수가 서로 연결된 구조로 설계되었다.
일주일(2023년 9월 1~7일) 간의 실증 결과, 연합 제어는 기존 제어 (실온을 기준으로 제어 변수 결정)와 비교하여 건물 순에너지 사용량에서 중앙값 기준으로 53.2% (사분위 범위 36.7%) 감소 효과를 보였다. 즉, 미래의 실의 열적 거동 및 태양광 발전량 변화 예측하고, 히트 펌프의 에너지 사용 특성(COP, PLR)과 에너지 효율 간의 관계를 이해하고, 시스템들 간의 동적 상호 작용을 파악함으로써 건물 제어의 에너지 절감 효과를 향상시킬 수 있다. 이때, 그 우수함은 제어 조건에 따라 확률적으로 변동할 수 있음에 유의해야 한다.
본 연구에서는 외부 환경, 실, 히트펌프 및 태양광 발전 시스템 간의 동적 상호작용을 고려한 연합 제어를 구현하고, 실제 사무용 건물의 냉방 제어 적용을 통해 연합 제어의 절감 원인을 분석하였다. 이를 통해 건물 에너지 절감을 위한 연합 제어의 우수성을 확률 분포로 정량화 하였다.Chapter 1. Introduction 8
1.1 Problem statement . 8
1.2 Objectives 12
1.3 Thesis outline 14
Chapter 2. Methodology 16
2.1 Data-driven modeling for building dynamics 16
2.2 Artificial Neural Network 17
Chapter 3. Target building . 20
Chapter 4. Local vs. Federated control 25
4.1 Federated simulation model 25
4.2 Model Predictive Control (MPC) 30
4.3 Baseline: Local control. 31
Chapter 5. Results 33
5.1 Comparative analysis 33
5.2 Stochastic characteristics of the federated MPC . 46
Chapter 6. Conclusion 50
References . 51석
Going Beyond Counting First Authors in Author Co-citation Analysis
Get PDFThe present study examines one of the fundamental aspects of author co-citation analysis (ACA) - the way co-citation
counts are defined. Co-citation counting provides the data on which all subsequent statistical analyses and mappings
are based, and we compare ACA results based on two different types of co-citation counting - the traditional type that
only counts the first one among a cited work's authors on the one hand and a non-traditional type that takes into
account the first 5 authors of a cited work on the other hand. Results indicate that the picture produced through this non-traditional author co-citation counting contains more coherent author groups and is therefore considerably clearer. However, this picture represents fewer specialties in the research field being studied than that produced through the traditional first-author co-citation counting when the same number of top-ranked authors is selected and analyzed. Reasons for these effects are discussed
Variations on the Author
Get PDF“Variations on the Author” discusses two of Eduardo Coutinho’s recent films (Um Dia na Vida, from 2010, and Últimas Conversas, posthumously released in 2015) and their contribution to the general question of documentary authorship. The director’s filmography is characterized by a consistent yet self-effacing form of authorial self-inscription: Coutinho often features as an interviewer that rather than express opinions propels discourses; an interviewer that is good at listening. This mode of self-inscription characterizes him as an author who is not expressive but who is nonetheless markedly present on the screen. In Um Dia na Vida, however, Coutinho is completely absent form the image, while Últimas Conversas, on the contrary, includes a confessional prologue that moves the director from the margins to the center of his films. This article examines the ways in which these works stand out in the filmography of a director who offers new insights into the notion of cinematic authorship
Appropriate Similarity Measures for Author Cocitation Analysis
Get PDFWe provide a number of new insights into the methodological discussion about author cocitation analysis. We first argue that the use of the Pearson correlation for measuring the similarity between authors’ cocitation profiles is not very satisfactory. We then discuss what kind of similarity measures may be used as an alternative to the Pearson correlation. We consider three similarity measures in particular. One is the well-known cosine. The other two similarity measures have not been used before in the bibliometric literature. Finally, we show by means of an example that our findings have a high practical relevance.information science;Pearson correlation;cosine;similarity measure;author cocitation analysis
Dispelling the Myths Behind First-author Citation Counts
Get PDFWe conducted a full-scale evaluative citation analysis study of scholars in the XML research field to explore just how different from each other author rankings resulting from different citation counting methods actually are, and to demonstrate the capability of emerging data and tools on the Web in supporting more realistic citation counting methods. Our results contest some common arguments for the continued
use of first-author citation counts in the evaluation of scholars, such as high correlations between author rankings by first-author citation counts and other citation
counting methods, and high costs of using more realistic citation counting methods that are not well-supported by the ISI databases. It is argued that increasingly available digital full text research papers make it possible for citation analysis studies to go beyond what the ISI databases have directly supported and to employ more
sophisticated methods
koamabayili/VECTRON-author-checklist: VECTRON author checklist
No full textWe have done our best to complete the author checklist relating to the use of animals in the hut study. Note that the objective for the hut study was to evaluate the IRS treatment applications for residual efficacy against Anopheles mosquitoes, including the local An. coluzzii mosquito population. Cows were only used to attract mosquitoes into the huts and no tests were carried out directly on the cows. The author checklist is intended for use with studies where experiments are carried out on animals, which is why we have had such difficulty in completing this for the hut study, as many of the questions do not relate to how the cows were used
Author-wise bibliometric analysis based on entropy.
No full textAuthor-wise bibliometric analysis based on entropy.</p
Author Under Sail The Imagination of Jack London, 1893-1902
No full textIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Intro -- Title Page -- Copyright Page -- Dedication -- Contents -- Acknowledgments -- Introduction -- 1. Spirit Truth -- 2. From Absorption to Theatricality and Back Again -- 3. "I Will Build a New Present" -- 4. Sons as Authors -- 5. Fathers as Publishers -- 6. The Daughter as Author -- 7. Lovers as Authors -- 8. At Sea with the Family -- 9. Yellow News, Yellow Stories -- 10. The Return Home -- Notes -- Bibliography -- Index -- About Jay WilliamsIn Author Under Sail, Jay Williams offers the first complete literary biography of Jack London as a professional writer engaged in the labor of writing. It examines the authorial imagination in London's work, the use of imagination in both his fiction and nonfiction, and the ways he defined imagination in the creative process in his business dealings with his publishers, editors, and agents. In this first volume of a two-volume biography, Williams traverses the years 1893 to 1902, from London's "Story of a Typhoon" to The People of the Abyss. The Jack London who emerges in the pages of Author Under Sail is a writer whose partnership with publishers, most notably his productive alliance with George Brett of Macmillan, was one of the most formative in American literary history. London pioneered many author models during the heyday of realism and naturalism, blurring the boundaries of these popular genres by focusing on absorption and theatricality and the representation of the seen and unseen. London created an impassioned, sincere, and extremely personal realism unlike that of other American writers of the time. Author Under Sail is a literary tour de force that reveals the full range of London as writer, creative citizen, and entrepreneur at the same time it sheds light on the maverick side of machine-age literature.Description based on publisher supplied metadata and other sources.Electronic reproduction. Ann Arbor, Michigan : ProQuest Ebook Central, YYYY. Available via World Wide Web. Access may be limited to ProQuest Ebook Central affiliated libraries
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