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"It is widely use of air-conditioning systems in Thailand due to its location. It is located in a tropical zone with relatively high temperatures all year round, with high humidity and high intensity of sunlight. In order to save electrical energy for air-conditioning systems, preventing heat transfer into the building is required. The objective of this study is to investigate the physical and thermal properties of concrete blocks. An attempt is made to increase heat resistance of concrete blocks. Foam beads (0−0.30% by weight) and kaolin (0−70% by weight) were added in concrete block mixture to increase discontinuous voids in concrete. Compressive strength and water absorption of concrete blocks were tested. The testing results indicated that compressive strength decreased when foam beads and kaolin were added. Water absorption increased when foam beads were added. In contrast, the more kaolin added the less water absorption. The thermal conductivity coefficient of concrete blocks was also investigated. The results confirmed that the higher the amount of foam beads or kaolin added, the higher the thermal resistance of concrete blocks. Thermal time-lag behavior was also investigated. The results indicated that concrete block with kaolin took the longest time in heating and took the shortest time in cooling. These properties are good for heat prevention in hot climate regions. These concrete blocks which were developed and tested in this research conform to the Thai Industrial Standard. Finally, it can be concluded that because of its thermal behavior, concrete block with kaolin is a suitable energy-saving concrete block for hot and humid climates."

"This book focuses on the integration of air conditioning and heating as a form of demand response into modern power system operation and planning. It presents an in-depth study on air conditioner aggregation, and examines various models of air conditioner aggregation and corresponding control methods in detail. Moreover, the book offers a comprehensive and systematic treatment of incorporating flexible heating demand into integrated energy systems, making it particularly well suited for readers who are interested in learning about methods and solutions for demand response in smart grids. It offers a valuable resource for researchers, engineers, and graduate students in the fields of electrical and electronic engineering, control engineering, and computer engineering."

"Teknologi air conditioning terutama untuk tujuan pendinginan kini lebih mengarah kepada penggunaan teknologi pendingin konvensional dengan dukungan sumber energi dari alam. Salah satunya adalah teknologi absorption chiller dengan bantuan energi surya untuk mendukung kerja komponen generator. Akan tetapi, kebanyakan sistem absorption chiller masih menggunakan media pendingin cooling water dari sistem menara pendingin yang membutuhkan area instalasi yang luas dan berbagai alat pendukung. Salah satu upaya yang dapat dilakukan adalah menggantikan penggunaan menara pendingin dengan pendinginan menggunakan udara lingkungan (air-cooled). Berdasarkan kajian literatur yang telah dilakukan, masih belum ada studi sebelumnya yang membahas sistem absorption chiller dengan larutan ammonia-water di Indonesia sebagai wilayah tropis yang memanfaatkan energi surya sebagai sumber panas pada generator, dan temperatur udara sebagai media pendingin di condenser dan absorber, maka pada penelitian ini dilakukan pemodelan, desain, serta analisis terkait kinerja dari sistem ini sesuai dengan kondisi iklim tropis di Indonesia. Metode yang dilakukan untuk penelitian ini meliputi pendalaman pemahaman konsep terkait desain termodinamika, perancangan dan perakitan komponen, dan simulasi lanjutan (dinamik dan transien) terhadap sistem. Penelitian ini memodelkan sistem absorption chiller dengan input temperatur kondensasi 38°C dan evaporasi 6°C untuk mencapai COP optimum sebesar 0,313 dan temperatur outlet generator 84,4°C. Simulasi menunjukkan bahwa konfigurasi ABS-WH1 memberikan kinerja energi dan eksergi yang lebih baik dibandingkan ABS-WH2 dalam aplikasi pendinginan dan pemanas air. Alat penukar kalor yang ideal adalah tipe finned tube untuk kondensor dan absorber, serta shell and tube untuk evaporator dan generator. Integrasi energi surya dan pemanas listrik dalam mengatasi fluktuasi radiasi matahari, dengan performa sistem yang berfluktuasi sesuai perubahan temperatur air panas dalam tangki penyimpanan.

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Air conditioning technology, primarily for cooling purposes, is now leaning towards the use of conventional cooling technologies supported by energy sources from nature. One of these is the absorption chiller technology, assisted by solar energy to support the operation of the generator components. However, most absorption chiller systems still use cooling water from cooling tower systems, which require a large installation area and various supporting equipment. One of the efforts that can be made is to replace the use of cooling towers with cooling using ambient air (air-cooled). Based on the literature review conducted, there has yet to be any previous studies discussing absorption chiller systems with ammonia-water solution in Indonesia as a tropical region utilizing solar energy as a heat source for the generator, and air temperature as the cooling medium in the condenser and absorber. Therefore, this research involves modeling, designing, and analyzing the performance of this system according to the tropical climate conditions in Indonesia. The methods used in this research include deepening the understanding of the concepts related to thermodynamic design, component design and assembly, and advanced simulation (dynamic and transient) of the system. This research models an absorption chiller system with a condensation temperature input of 38°C and evaporation of 6°C to achieve an optimum COP of 0.313 and a generator outlet temperature of 84.4°C. The simulation shows that the ABS-WH1 configuration provides better energy and exergy performance compared to ABS-WH2 in cooling and water heating applications. The ideal heat exchanger is a finned tube type for the condenser and absorber, and shell and tube for the evaporator and generator. The integration of solar energy and electric heating addresses fluctuations in solar radiation, with the system's performance fluctuating according to changes in the hot water temperature in the storage tank."

"Sistem tata udara presisi merupakan sistem multivariabel yang mempunyai beberapa masukan dan keluaran (MIMO). Hal ini menyebabkan mencari model fisik dari sistem ini menjadi relatif sulit. Sehingga diperlukan identifikasi sistem yang bersifat black box. Selain itu, dibutuhkan identifikasi model yang bersifat adaptif, sehingga model yang didapat lebih baik dalam merepresentasikan sistem tata udara presisi. Identifikasi model ruang keadaan multivariabel pada sistem tata udara presisi dilakukan dengan menggunakan metode 4SID. Sistem tata udara presisi direpresentasikan dalam model linear dan sistem tidak linear. Model linear didapat dari model ruang keadaan, sedangkan sistem tidak linear didapat dari persamaan matematis sistem tersebut. Metode 4SID yang digunakan adalah MOESP rekursif dan PO-MOESP rekursif. Setelah didapat model ruang keadaan menggunakan kedua metode tersebut, selanjutnya dilakukan tes validasi dari model ruang keadaan yang didapat. Parameter yang digunakan untuk mengetahui tingkat validasi identifikasi adalah menggunakan nilai kesalahan (Jee). Selain itu, pada penelitian ini juga dituliskan hasil identifikasi model ruang keadaan menggunakan metode linearisasi dan N4SID offline. Hasil identifikasi secara offline yang terbaik dari model linear yang dilakukan adalah menggunakan metode N4SID. Untuk identifikasi secara rekursif, metode MOESP rekursif dan PO-MOESP rekursif pada penelitian ini belum dapat merepresentasikan sistem tidak linear. Metode-metode identifikasi rekursif ini relatif baik dalam mengidentifikasi model tidak linear dari sistem tata udara presisi berdasarkan nilai kesalahan (Jee). Pada penelitian ini, MOESP rekursif untuk identifikasi model linear menghasilkan model yang lebih baik disbanding PO-MOESP rekursif berdasarkan nilai kesalahan (Jee) juga.

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Precision Air Conditioning System is a multivariable system with multi input and multi output (MIMO). It makes difficult to find out physical model of this system. Therefore, it is necessary to identify system using black box model. Besides, it is also necessary to identify model adaptively, so that it could represent the system better.

Identification of multivariable state space model in precision air conditioning system uses 4SID method. PAC system is represented by linear model and nonlinear system. Linear model of PAC is formed by state space model, and nonlinear system is formed by mathematical modeling of such system. 4SID methods that used are recursive MOESP and recursive PO-MOESP. After state space model is formed, the state space model is validated. Parameter that used for this validation is lost function (Jee). In this research, there are also identifications of state space model using linearization method and offline N4SID method.

The best result of offline identification of linear model in this research is N4SID method. In recursive identification, recursive MOESP and recursive PO-MOESP could not represent nonlinear system well. These recursive algorithms could represent linear model well based on criterion of lost function (Jee). In this research, the result of recursive MOESP identification is better than recursive PO-MOESP based on criterion of lost function (Jee) also."