Reverberation chambers a la carte: An overview of the different mode-stirring techniques

Reverberation chambers (RC), a name inspired in room acoustics, are also known in literature as reverberating, reverb, mode-stirred or mode-tuned chambers. In their basic form, they consist of a shielded metallic enclosure, forming a cavity resonator, together with some mode-stirring mechanism. The main goal of such stirring mechanism is to generate an amplitude-varying electromagnetic field that is ideally statistically uniform

THERMAL ENERGY CONVERSION USING NANO RECTENNA ARRAYS (THE MAIN FOCUS IS ON THE AUTOMOTIVE SECTOR).

This research work is concerned with the study, design and fabrication of an energy harvester for converting radiant heat to electricity using rectenna technology, with key application being on the automobiles. A review of previous works of other researchers is presented, and the main limitations hindering the realisation of a practical and functional rectenna device as well as the main factors for optimising device performance highlighted. The temperature profile of an automobile engine and exhaust was measured in order to determine the operable temperature ranges, which is a key factor when determining the optimum device dimension. The contact angles made by a 5μl drop of water on surfaces coated with different self-assembled monolayers (SAMs) were measured in order to determining the hydrophilicity and hydrophobicity of the surfaces. This gives an idea the surface energy of the dielectric films, thus giving an indication of how uniform a surface coated with such dielectric film will be. Finally, a setup for the low frequency characterisation of the diode was made and validated using ordinary diodes

The Random Line-of-Sight Over-the-Air Measurement System

As our society becomes increasingly connected, a growing number of devices rely on wireless connectivity. The type, use and form factor of these devices range from wearables to entire vehicles. Additionally, the fifth generation of wireless communication (5G) introduces new communication bands, also at higher frequencies. At these millimeter-wave frequencies, large portions of bandwidth are available which are needed in order to increase the data rates.In this scenario, testing and verifying the wireless communication performance has an increasingly important role. In modern devices, testing needs to be performed over-the-air (OTA), as direct conducted measurements to the antenna ports become unfeasible. Moreover, there is still ongoing research to understand how testing should be performed for devices with large form-factors, such as vehicles, as well as for higher frequencies. The proposed methods are mainly based on techniques for mobile phone testing at the current communication bands, i.e., sub-6 GHz. However, scaling and adapting these methods to work for future needs presents challenges. A possible solution to meet the future testing requirements is offered by the following hypothesis: "If a wireless device is tested with good performance in both pure-LOS and RIMP environments, it will also perform well in real-life environments and situations, in a statistical sense". The rich isotropic multipath (RIMP) and the random line-of-sight (random-LOS) are therefore identified as the two representative edge environments for testing. This thesis focuses on the random-LOS environment, and its practical realization to test the wireless performance of different devices. The thesis is divided into three main parts. The first part describes the practical realization of random-LOS OTA measurement setups. Three different setups are presented, a virtual planar array and two reflector antennas. One reflector system is aimed at vehicular testing for frequencies below 6 GHz, while the other targets smaller devices at 28 GHz. The second part of the thesis focuses on numerical and experimental verification of the random-LOS measurement setups. In the verification, numerical simulations and measurements of the test zone variations are compared for the proposed OTA measurement systems.The third and last part focuses on how passive and active measurements can be performed using a random-LOS measurement setup. The measurements demonstrate the application of the designed OTA measurement systems for passive antenna measurements, as well as active 2x2 multiple-input multiple-output (MIMO) measurements on a complete vehicle

루테늄/전도성 고분자 하이브리드 나노입자 제조 및 수소 화학센서로의 응용

학위논문(박사)--서울대학교 대학원 :공과대학 화학생물공학부,2019. 8. 장정식.최근 우수한 물성과 전기적, 화학적 성능을 보이는 나노재료의 연구와 개발에 대해 지대한 관심이 있다. 특히, 무기물과 유기물을 결합한 복합나노재료는 각 물질의 상호작용으로 서로의 단점을 보완하고 우수한 물성을 보이기에 많은 산업분야에서 연구가 진행 중이다. 그 중에서도 금속과 전도성 고분자를 결합한 복합나노재료는 고분자의 낮은 기계적 특성을 보완해주고 금속 나노재료의 응집 현상을 막아주어 높은 안정성을 가지고 있다. 또한 뛰어난 성능의 전기적 특성을 가지고 있기 때문에 전기화학센서, 형광센서, 촉매, 에너지 변환 및 저장 장치에서 주목 받고 있다. 하지만, 현재 일정한 형태의 복합나노재료를 제조하는 기술이 부족하고 적용하는 금속 또한 백금, 금, 은 등의 안정성이 높은 귀금속에만 국한되어 있기 때문에 더 많은 연구가 필요한 상황이다. 스마트 화학센서는 트랜스듀서를 기반으로 하는 장치로 특징 있는 환경적 요소들을 감지하는데 뛰어난 성능을 보인다. 센서는 타겟물질을 감지하는 센싱 트랜스듀서가 필요한데 이 트랜스듀서는 전기, 온도, 형광 등 다양한 신호의 변화를 통해 타겟물질을 감지할 수 있으며 트랜스듀서가 감지한 신호를 디지털 신호로 바꾸어 디지털 기기를 통해 타겟물질의 유무 및 농도 변화를 확인하여 위험하고 폭발 가능성이 있는 기체에 대해 미리 알려주는 역할을 할 수 있기에 뛰어난 성능을 가진 센서는 많은 산업분야에서 유용하게 사용될 수 있다. 따라서, 뛰어난 감지 성능을 가지는 센싱 트랜스듀서 물질개발은 중요한 요소 중 하나이다. 뛰어난 성능을 판단하는 기준은 다음의 6가지 기준을 제시할 수 있다: 1) 높은 감도; 2) 넓은 범위의 감지 농도; 3) 타겟물질에 대한 선택성; 4) 빠른 감지와 회복 속도; 5) 반복감지에 대한 안정성; 6) 상온에서의 감지가능, 이렇게 6가지의 성능에 대한 테스트가 필요하다. 본 학위 논문에서는 전도성 고분자의 일종인 폴리피롤 나노입자 위에 금속물 중 하나인 루테늄 나노구조물이 올라간 일정한 형태의 금속과 전도성 고분자의 하이브리드 복합나노재료를 간단하고 창의적인 방법을 이용하여 제조하고, 이들의 전기적 물성을 체계적으로 고찰하여 센서용 트랜스듀서로 적용하는 연구를 기술하였다. 우선, 카르복실기를 함유한 폴리피롤 나노입자를 제조하고 이를 분산한 수용액에 루테늄 전구체를 넣어 초음파처리와 화학적 환원을 통해 루테늄 나노입자가 일정하게 박힌 폴리피롤 나노입자를 제조하였다. 이때, 루테늄 전구체의 농도를 조절하여 폴리피롤 나노입자 표면에 도입되는 루테늄 나노입자의 밀도를 조절하였으며 루테늄 나노입자의 밀도에 따른 수소 감지성능을 비교하였다. 그 결과, 루테늄 나노입자의 밀도가 증가함에 따라 센서가 감지할 수 있는 수소가스의 농도가 낮아지고 더 넓은 농도범위의 수소가스를 감지할 수 있는 것을 확인하였다. 더 나아가, 산 용액과 염기 용액을 이용하여 복합나노입자에 화학적 처리를 했을 시 루테늄 나노입자와 폴리피롤 나노입자에 어떤 구조적 변화가 발생하고 이 변화가 수소감지 성능에 미치는 영향에 대하여 연구하였다. 결과에 따르면 산과 염기 용액 처리에 의해서 루테늄 나노입자의 구조에는 변화가 생기지 않는 것을 확인하였다. 하지만, 처리하는 용액의 pH가 낮아질수록 폴리피롤의 고분자 구조가 이중 분극자 형태의 구조를 가지는 것을 확인 할 수 있었다. 이에 따라 트랜스듀서가 수소를 감지하는 속도와 감지 후 원상태로 회복하는 속도가 더 빨라지는 것을 확인 할 수 있었다. 감지농도와 감지가능한 농도범위에는 큰 변화가 발생하지 않는 것을 통해 수소감지에는 루테늄이 필수적으로 필요한 것 또한 확인 가능하였다. 마지막으로, IoT 시대가 도래함에 따라 이에 맞춰 제조한 트랜스듀서를 무선센서로 응용하는 연구를 진행하였다. 수동적 RFID 무선태그를 이용하면 배터리가 없이 신호를 주고 받을 수 있어 소형화가 가능하고 환경을 고려하지 않고 어디에든 적용가능한 무선센서를 제조할 수 있다. 이를 위해 RFID 무선태그의 일정부분에 산소 플라즈마와 화학적 처리를 통하여 아미노 관능기를 도입하였고 촉매를 이용하여 폴리피롤 나노입자 표면의 카르복실기와 공유결합시켜 안정적이고 단단하게 트랜스듀서 물질을 RFID 무선태그 표면에 도입하는 실험을 진행하였다. 그 결과, 수소가스의 유무에 따라 무선신호가 변화하는 것을 확인하였고 농도의 변화에 따라서도 신호변화 크기가 달라져 농도 측정 또한 가능한 것을 확인하였다. 정리하면, 본 학위 논문에서는 폴리피롤 나노입자 표면에 루테늄 나노입자를 고르게 도입하여 표면적이 극대화되고 수소에 대하여 선택적으로 반응할 수 있는 복합나노재료를 제조하였으며 수소화학센서와 무선센서로 응용 가능성에 대한 연구를 수행하였다. 본 학위 논문에서 사용된 간단하고 독창적 제조방법과 구조 변형 방법들은 다양한 나노물질의 제조에도 응용 가능할 것으로 기대된다.Recently, nanomaterial research receives attention due to excellent physical and chemical properties and electrical characters. Especially, inorganic and organic components hybrid nanomaterials are researched in various industrial areas because each component complements weaknesses and strengthens advantages. In particular, hybrid nanomaterials with metal and conducting polymer prevent poor mechanical properties such as brittleness and deficient processibility of polymeric nanomaterials and lack of stability due to the Ostwald ripening process of low dimensional metal nanaomaterials. Also, the combination of metallic materials with polymeric compounds provides an excellent functionality with high performance as well as enhanced stability and good processability. However, the limitation of applied metal, only Pt, Au, and Ag, and fabrication method of uniform hybrid nanomaterials are important tasks for researchers. Smart chemical sensor is transducer based device which has excellent performance to detect environmental elements. It needs sensing materials to detect target analyte which display electrical, thermal, or optical signal change by target analyte. High-performance sensing transducer is absolutely wanted because the sensor has to preindicate combustible, flammable, and toxic gases, monitoring air-fuel ratio in combustion engines, detecting food spoilage, and ambient oxygen level monitoring to prevent dangerous situations in diverse industrial environments. There are six standards to decide high-performance sensing transducer: 1) low minimum detectable level (MDL) to target analyte; 2) Wide detection range; 3) Selectivity; 4) Fast response and recovery time; 5) Cycle stability; 6) Sensing ability at room temperature. This dissertation describes facile and creative method to fabricate ruthenium nanoclusters decorated carboxylic polypyrrole nanoparticles, studies electrical and structural characters of composites scienctifically, and suggests them as sensing transducer for hydrogen sensor. First, carboxyl functional groups included polypyrrole nanoparticles (CPPyNPs) were fabricated by microemulsion. Then, ultrasonication and chemical reducing agent methods were used to embed ruthenium nanoclusters, reduced from ruthenium precursors, on the surface of carboxylated polypyrrole nanoparticles. Furthermore, the density of ruthenium nanoclusters on the CPPyNP surface was controlled by injected ruthenium precursor concentration and the effect of variable ruthenium densities on CPPyNP surface for hydrogen sensing performance was analyzed. As a result, higher ruthenium density on CPPyNP surface showed lower minimum detectable level and wider detecting range for hydrogen gas detection. Second, chemical treatment by acid and base aqueous solvents was processed to Ru/CPPyNPs and structural changes of ruthenium nanoclusters and CPPyNPs were observed. There was no transition in ruthenium nanoclusters. However, polypyrrole polymer chain was reversibly changed among neutral, polaron, and bipolaron states by treatment of acid and base aqueous solvents. Hence, the response and recovery times of hydrogen gas detection were changed due to transition of charge carrier (hole) density and mobility in polypyrrole backbone structure. At last, Ru/CPPyNPs application as sensing material for wireless chemical sensor was demonstrated because the wireless chemical sensor becomes important technology for future IoT age. Especially, passive RFID tag is focused for wireless sensor because no battery is needed for tag operation. Thus, miniaturization and adaptation of wireless sensor is practicable. For these purposes, oxygen plasma and silane treatment were applied to the part of RFID tag to introduce amino functional groups and these groups were connected with carboxyl functional groups on CPPyNPs rigidly and stably. As a result, the reflectance change by hydrogen gas was displayed and the amount of change was differed from various hydrogen gas concentrations. Clearly, this dissertation proves the facile fabrication of ruthenium nanoclusters uniformly decorated carboxylated polypyrrole nanoparticles and the possibility of application for hydrogen chemical sensor and wireless sensor. The facile and creative hybrid nanocomposites fabrication method and chemical treatment to modify structural chain are expected to utilize for fabrication of other nanomaterials.Abstract i List of Abbreviations v List of Figures x List of Tables xx Table of Contents xxi 1. Introduction 1 1.1. Background 1 1.1.1. Conducting polymer 1 1.1.1.1. Doping 5 1.1.1.2. Polypyrrole 8 1.1.2. Nanomaterial 14 1.1.2.1. Conducting polymer nanomaterial 17 1.1.2.1.1. Polypyrrole nanoparticle 22 1.1.2.2. Metal nanomaterial 24 1.1.2.3. Metal/Conducting polymer hybrid nanomaterial 27 1.1.3. Sensor application 29 1.1.3.1. Resistive chemical sensor 31 1.1.3.1.1. Hydrogen gas sensor 34 1.1.3.2. Wireless sensor 35 1.1.3.2.1. RFID wireless sensor 36 1.2. Objectives and Outlines 38 1.2.1. Objectives 38 1.2.2. Outlines 38 2. Experimental Details 41 2.1. Ruthenium/polypyrrole hybrid nanoparticle for hydrogen chemical sensor 41 2.1.1. Materials 41 2.1.2. Fabrication of ruthenium/polypyrrole hybrid nanoparticle 41 2.1.3. Electrical measurement of Ru/CPPyNP attached chemiresistive sensor 43 2.1.3. Characterization 44 2.2. Acid-base treatment of Ru/CPPyNPs to control the chemiresistive properties of hydrogen chemical sensor 48 2.2.1. Materials 48 2.2.2. Acid-base treatment of Ru/CPPyNPs 48 2.2.3. Electrical measurement of acid-base treated Ru/CPPyNP attached chemiresistive sensor 49 2.2.4. Characterization 50 2.3. Wireless hydrogen sensor application of Ru/CPPyNPs 52 2.3.1. Materials 52 2.3.2. Fabrication of Ru/CPPyNPs introduced UHF-RFID wireless sensor 52 2.3.3. Radio frequency measurement of the Ru/CPPyNPs attached UHF-RFID wireless hydrogen sensor 54 2.3.4. Characterization 55 3. Results and Disccusion 56 3.1. Ruthenum/polypyrrole hybrid nanoparticle for hydrogen chemical sensor 56 3.1.1. Fabrication of Ru/CPPyNP 56 3.1.2. Material analysis of Ru/CPPyNP 64 3.1.3. Characterization of Ru/CPPyNP chemiresistive sensor electrode 69 3.1.4. Electrical measurement of Ru/CPPyNP based hydrogen gas chemical sensor 73 3.2. Acid-base treatment of Ru/CPPyNPs to control the chemiresistive properties of hydrogen chemical sensor 87 3.2.1. Morphology change observation of Ru/CPPyNPs by acid-base treatment 87 3.2.2. Material analysis of acid and base treated Ru/CPPyNPs 94 3.2.3. Electrical characterization for acid and base solvents treated Ru/CPPyNPs 103 3.2.4. Electrical measurement of acid and base treated Ru/CPPyNPs based hydrogen gas chemical sensor 106 3.3. Wireless hydrogen sensor application of Ru/CPPyNPs 118 3.3.1. Fabrication of UHF-RFID based wireless hydrogen gas sensor 118 3.3.2. Wireless sensor measurement of Ru/CPPyNPs attached UHF-RFID tag 123 3.3.3. Flexibility test of Ru/CPPyNPs attached UHF-RFID tag for wireless hydrogen sensor 135 4. Conclusion 139 Reference 143 국문초록 151Docto

Review of applications of the Laboratory for Electromagnetic Compatibility infrastructure

This article provides a thorough description of a range of non-standard application cases in which EMC laboratories can be used other than those traditionally associated with this kind of facilities. The areas covered here include investigations of: wireless and radio systems (such as IoT and broadband radio systems) also that require ultra-high operational dynamic range, emulation of interference-free and/or heavily-multipath propagation environment, shielding effectiveness of cabinets and materials (i.e. thin, light and flexible as textiles as well as heavy and thick such as building construction elements)

금속 나노입자가 도입된 다채널 탄소 나노 섬유 제조 및 바이오/화학 센서로의 응용

학위논문 (박사) -- 서울대학교 대학원 : 공과대학 화학생물공학부(에너지환경 화학융합기술전공), 2020. 8. 장정식.In recent decades, nanomaterial research and the synthesis methods of novel nanomaterials with improved physical, chemical, and electrical properties are continuously expanding frontier at the material science. Among them, conductive nanomaterials including conducting polymers, nanostructured metal composite, and carbon nanomaterials have been studied because of their unique properties. One-dimensional (1D) conductive nanomaterials have been shown to be particularly effective sensor transducers due to their simple structure properties such as high aspect ratio and high specific surface area, and fast directional charge transport characteristics. One of the 1D conductive nanomaterials, carbon nanomaterials are important for electrochemical and biological applications since their surface can be easily modified using a variety of covalent or π-stacking methods. Especially, carbon nanofibers (CNFs) can be obtained via a simple electrospinning method, one of the methods for manufacturing 1D nanomaterials using a viscous polymer solution, has advantages relatively in terms of efficiency, cost, yield, and reproducibility. Electrospun CNFs are particularly attractive for sensing applications because their electrochemical properties and structures can be easily controlled by varying the process conditions, including temperature, spinning solution component, precursor composition, etc. However, there remain some challenges such as the production of multidimensional nanofibers or hybrid nanomaterials require the optimization of a stable process for electrochemical and structural benefits. This dissertation describes the fabrication of various hybrid materials using electrospun PAN-based multichannel carbon nanofibers for bio and chemical sensor applications. The multichannel carbon nanofibers were fabricated through single-nozzle co-electrospinning and heat treatment. It was confirmed that multichannel carbon nanofiber has utility as a sensor transducer through the biosensor applications. Firstly, bio-receptors-modified multichannel carbon nanofibers were prepared using the acid treatment and following catalytic reaction between the carboxyl group of the multichannel carbon nanofibers and the amine group of the bio-receptors. According to the bio-receptors, aptamers were applied for detecting the endocrine disruptor (bisphenol-A, BPA) and antibodies were applied for detecting the salivary epilepsy biomarker (nesfatin-1, NES1). Secondly, noble metal (Ru) and metal oxide (Fe2O3) nanoparticles-embedded multichannel carbon nanofibers were suggested by the facile method including oxygen plasma treatment before heat treatment. The ruthenium nanoparticles-embedded multichannel carbon nanofibers (Ru-mCNFs) were applied for detecting neurotransmitter molecule (dopamine) and the iron oxide nanoparticles-embedded multichannel carbon nanofibers (Fe-mCNFs) were applied for detecting toxic gas (hydrogen sulfide). This dissertation provides the possibility and facile fabrication methods of various types of multichannel carbon nanofibers-based hybrid nanomaterials exhibited ultrahigh ability in the bio/chemical sensor application due to its large active surface area originated from the multichannel and porous structure. The nanomaterials presented in this dissertation could be applied to various sensing systems such as liquid-ion-gated bio-receptor (aptamer or antibody) field-effect-transistor (FET) sensor, non-enzymatic FET sensor, and toxic gas wireless chemical sensor platform.최근 물리적, 화학적, 전기적 특성이 개선된 나노 물질 연구와 새로운 나노 물질의 합성 방법이 재료 과학에서 지속적으로 발전하고 있다. 그 중에서도, 전도성 고분자, 나노 구조 금속 복합재 및 탄소 나노 재료를 포함하는 전도성 나노 재료는 그 고유한 특성으로 인해 많이 연구되어왔다. 1 차원 (1D) 전도성 나노 물질은 높은 종횡비와 높은 비표면적 및 빠른 방향 전하 수송 특성과 같은 단순한 구조 특성으로 인해 특히 센서 변환기로써 효과적인 것으로 알려져 있다. 1D 전도성 나노 물질 중 하나인 탄소 나노 물질은 공유결합, π-스태킹과 같은 다양한 방법을 사용하여 표면을 개질할 수 있어 전기 화학 및 생물학적 응용에 중요하다. 특히, 탄소 나노 섬유 (CNF)는 점성 고분자 용액을 사용하여 1D 나노 물질을 제조하는 방법 중 하나인 전기 방사법을 통해 간단히 얻을 수 있으며, 효율, 비용, 수율 및 재현성 측면에서 상대적으로 유리하다. 전기 방사된 탄소 나노 섬유는 온도, 방사 용액 성분, 전구체 조성 등을 포함하여 공정 조건을 변경하여 전기 화학적 특성 및 구조를 쉽게 제어할 수 있기 때문에 센서 응용 분야에 특히 매력적이다. 그러나 다차원 나노 섬유 생산 또는 하이브리드 나노 물질 제조에 있어서 전기 화학적 및 구조적 이점을 위해 안정적인 공정 최적화가 필요하다. 이 논문은 바이오 및 화학 센서 응용을 위해 전기 방사된 폴리아크릴로나이트릴 (PAN) 기반 다중 채널 탄소 나노 섬유를 사용하는 다양한 하이브리드 재료의 제조를 설명한다. 다채널 탄소 나노 섬유는 단일 노즐 공동 전기 방사 및 열처리를 통해 제조되었다. 다채널 탄소 나노 섬유는 바이오 센서 응용을 통한 센서 변환기로서의 유용성을 갖는 것을 확인할 수 있었다. 첫째로, 산 처리를 거친 다채널 탄소 나노 섬유의 카르복실기와 바이오 수용체의 아민기 사이의 촉매 반응에 따라 생체 수용체가 고정된 다채널 탄소 나노 섬유를 제조하였다. 생체 수용체에 따라서 내분비계 교란 물질 (비스페놀-A, BPA)을 검출하기 위해서 압타머를 사용하였고 타액 간질 바이오 마커 (네스파틴-1, NES1)를 검출하기 위해서는 항체를 도입하였다. 둘째, 열처리 전 산소 플라즈마 처리를 포함하는 손쉬운 방법으로 귀금속 (Ru) 및 금속 산화물 (Fe2O3) 나노입자가 도입된 다채널 탄소 나노 섬유를 제안하였다. 루테늄 나노입자가 도입된 다채널 탄소 나노 섬유 (Ru-mCNF)는 신경 전달 물질 분자 (도파민)의 검출을 위해 사용되었고, 산화철 나노입자가 도입된 다채널 탄소 나노 섬유 (Fe-mCNF)는 독성 가스 (황화수소)를 검출하기 위해 적용되었다. 이 논문은 다채널 및 다공성 구조로부터 유래된 큰 활성 표면적으로 인해 바이오/화학 센서 응용에서 초고성능을 나타내는 다양한 유형의 다채널 탄소 나노 섬유 기반 하이브리드 나노 재료의 가능성 및 용이한 제조 방법을 제공한다. 이 논문에 제시된 나노 물질은 액체 이온 게이트 바이오 리셉터 (압타머 또는 항체) 전계 효과 트랜지스터 (FET) 센서, 비 효소 형 FET 센서, 독성 가스 무선 화학 센서 플랫폼과 같은 다양한 감지 시스템에 도입될 수 있다.1. Introduction 1 1.1. Background 1 1.1.1. Conductive nanomaterial 1 1.1.1.1. One-dimensional (1D) nanomaterial 10 1.1.1.1.1. Electrospinning method 12 1.1.1.1.2. Electrospinning-based carbon nanomaterial 17 1.1.1.2. Hybrid nanomaterial 24 1.1.1.2.1. Noble metal/carbon nanomaterial 27 1.1.1.2.2. Metal oxide/carbon nanomaterial 28 1.1.2. Sensor application 29 1.1.2.1. Liquid-ion-gated FET biosensor 31 1.1.2.1.1. Bisphenol-A (BPA) sensor 34 1.1.2.1.2. Nesfatin-1 (NES1) sensor 36 1.1.2.1.3. Dopamine (DA) sensor 38 1.1.2.2. Resistive type chemical sensor 40 1.1.2.2.1. Hydrogen sulfide (H2S) sensor 44 1.1.2.3 Wireless sensor 45 1.1.2.3.1. RFID wireless sensor 46 1.2. Objectives and Outlines 48 1.2.1. Objectives 48 1.2.2. Outlines 49 2. Experimental Details 51 2.1. Bio-receptors-modified multichannel carbon nanofibers for liquid-ion-gated FET sensor detecting bisphenol-A and nesfatin-1 51 2.1.1. Fabrication of bio-receptors-modified MCNFs FET sensor (anti-BPA aptamer & anti-NES1 antibody) 51 2.1.2. Characterization 55 2.1.3. Electrical measurement 56 2.2. Ruthenium nanoparticles-embedded multichannel carbon nanofibers for liquid-ion-gated non-enzymatic FET sensor detecting dopamine 57 2.2.1. Fabrication of Ru-mCNFs non-enzymatic FET sensor 57 2.2.2. Characterization 59 2.2.3. Electrical measurement 60 2.3. Iron oxide nanoparticles-embedded multichannel carbon nanofibers for wireless chemical sensor detecting hydrogen sulfide 61 2.3.1. Fabrication of Fe-mCNF 61 2.3.2. Characterization 62 2.3.3. Electrical measurement 63 2.3.4. Fabrication of Fe-mCNFs UHF-RFID wireless sensor 64 2.3.5. Wireless sensor measurement 65 3. Results and Discussion 68 3.1. Bio-receptors-modified multichannel carbon nanofibers for liquid-ion-gated FET sensor detecting bisphenol-A and nesfatin-1 68 3.1.1. Fabrication of carboxyl-functionalized MCNFs (cMCNFs) 68 3.1.2. Fabrication of bio-receptors-modified MCNFs FET sensors (anti-BPA aptamer & anti-NES1 antibody) 77 3.1.3. Electrical measurement of anti-BPA aptamer-modified MCNFs (A-MCNFs) FET sensor detecting BPA 83 3.1.4. Electrical measurement of anti-NES1 antibody-modified MCNFs (Ab-MCNFs) FET sensor detecting NES1 97 3.2. Ruthenium nanoparticles-embedded multichannel carbon nanofibers for liquid-ion-gated non-enzymatic FET sensor detecting dopamine 105 3.2.1. Fabrication of Ru-mCNFs 105 3.2.2. Fabrication of Ru-mCNFs non-enzymatic FET sensor 120 3.2.3. Electrical measurement of Ru-mCNFs non-enzymatic FET sensor 122 3.3. Iron oxide nanoparticles-embedded multichannel carbon nanofibers for resistive type wireless chemical sensor detecting hydrogen sulfide 134 3.3.1. Fabrication of Fe-mCNFs 134 3.3.2. Electrical measurement of Fe-mCNFs chemical sensor 146 3.3.3. Wireless sensor measurement of Fe-mCNFs UHF-RFID wireless sensor 153 4. Conclusion 161 Reference 166 국문초록 180Docto

Antenna Designs Aiming at the Next Generation of Wireless Communication

Millimeter-wave (mm-wave) frequencies have drawn large attention, specically for the fifth generation (5G) of wireless communication, due to their capability to provide high data-rates. However, design and characterization of the antenna system in wireless communication will face new challenges when we move up to higher frequency bands. The small size of the components at higher frequencies will make the integration of the antennas in the system almost inevitable. Therefore, the individual characterization of the antenna can become more challenging compared to the previous generations.This emphasizes the importance of having a reliable, simple and yet meaningful Over-the-Air (OTA) characterization method for the antenna systems. To avoid the complexity of using a variety of propagation environments in the OTA performance characterization, two extreme or edge scenarios for the propagation channels are presented, i.e., the Rich Isotropic Multipath (RIMP) and Random Line-of-Sight (Random-LoS). MIMO efficiency has been defined as a Figure of Merit (FoM), based on the Cumulative Distribution Function (CDF) of the received signal, due to the statistical behavior of the signal in both RIMP and Random-LoS. Considering this approach, we have improved the design of a wideband antenna for wireless application based on MIMO efficiency as the FoM of the OTA characterization in a Random-LoS propagation environment. We have shown that the power imbalance and the polarization orthogonality plays major roles determining the 2-bitstream MIMO performance of the antenna in Random-LoS. In addition, a wideband dual-polarized linear array is designed for an OTA Random-LoS measurement set-up for automotive wireless systems. The next generation of wireless communications is extended throughout multiple narrow frequency bands, varying within 20-70 GHz. Providing an individual antenna system for each of these bands may not be feasible in terms of cost, complexity and available physical space. Therefore, Ultra-Wideband (UWB) antenna arrays, coveringmultiple mm-wave frequency bands represent a versatile candidate for these antenna systems. In addition to having wideband characteristics, these antennas should offer an easy integration capability with the active modules. We present a new design of UWB planar arrays for mm-wave applications. The novelty is to propose planar antenna layouts to provide large bandwidth at mm-wave frequencies, using simplified standard PCB manufacturing techniques. The proposed antennas are based on Tightly Coupled Dipole Arrays (TCDAs) concept with integrated feeding network

New advances in vehicular technology and automotive engineering

An automobile was seen as a simple accessory of luxury in the early years of the past century. Therefore, it was an expensive asset which none of the common citizen could afford. It was necessary to pass a long period and waiting for Henry Ford to establish the first plants with the series fabrication. This new industrial paradigm makes easy to the common American to acquire an automobile, either for running away or for working purposes. Since that date, the automotive research grown exponentially to the levels observed in the actuality. Now, the automobiles are indispensable goods; saying with other words, the automobile is a first necessity article in a wide number of aspects of living: for workers to allow them to move from their homes into their workplaces, for transportation of students, for allowing the domestic women in their home tasks, for ambulances to carry people with decease to the hospitals, for transportation of materials, and so on, the list don’t ends. The new goal pursued by the automotive industry is to provide electric vehicles at low cost and with high reliability. This commitment is justified by the oil’s peak extraction on 50s of this century and also by the necessity to reduce the emissions of CO2 to the atmosphere, as well as to reduce the needs of this even more valuable natural resource. In order to achieve this task and to improve the regular cars based on oil, the automotive industry is even more concerned on doing applied research on technology and on fundamental research of new materials. The most important idea to retain from the previous introduction is to clarify the minds of the potential readers for the direct and indirect penetration of the vehicles and the vehicular industry in the today’s life. In this sequence of ideas, this book tries not only to fill a gap by presenting fresh subjects related to the vehicular technology and to the automotive engineering but to provide guidelines for future research. This book account with valuable contributions from worldwide experts of automotive’s field. The amount and type of contributions were judiciously selected to cover a broad range of research. The reader can found the most recent and cutting-edge sources of information divided in four major groups: electronics (power, communications, optics, batteries, alternators and sensors), mechanics (suspension control, torque converters, deformation analysis, structural monitoring), materials (nanotechnology, nanocomposites, lubrificants, biodegradable, composites, structural monitoring) and manufacturing (supply chains). We are sure that you will enjoy this book and will profit with the technical and scientific contents. To finish, we are thankful to all of those who contributed to this book and who made it possible.info:eu-repo/semantics/publishedVersio

CHARACTERIZATION AND HANDLING OF UNCERTAINTIES IN EMC/EMI MEASUREMENTS

Ph.DDOCTOR OF PHILOSOPH

Closed-form expressions for the total power radiated by an electrically long multiconductor line

International audienceTwo analytical solutions based on transmission-line theory for the total power radiated by a multiconductor line above a ground-plane are proposed. The line is not assumed to be electrically short or close to the ground-plane, thus making the proposed model suitable for assessing the emission/immunity of actual transmission-lines employed in industrial contexts such as in the automotive domain, in railway lines and power-distribution lines. The model allows an imperfect ground plane to be considered through the complex-image approximation, together with propagation losses. Numerical and experimental results are provided as a validation, while an empirical rule to assess the accuracy of the results is proposed. The two expressions aim at allowing fast parametric analysis of radiation during the design phase of the electrical and geometrical configuration of an unshielded MTL