Article
Engineering, Electrical & Electronic
Sebastian Martins, Alysson R. Seidel, Marina S. Perdigao, Leandro Roggia
Summary: The main objective of this paper is to analyze and achieve inductor core volume reduction based on non-linear inductance design techniques for a PV DC-DC Converter, and to perform a comparison of volume and efficiency among usual design techniques. The paper presents two different non-linear inductance techniques for inductor design and compares them with usual techniques in a photovoltaic system.
ELECTRIC POWER SYSTEMS RESEARCH
(2022)
Article
Chemistry, Multidisciplinary
Sithara Gopinath, Nayarassery N. Adarsh, Pankajakshan Radhakrishnan Nair, Suresh Mathew
Summary: The study focused on the effect of nano-metallic-oxide fillers on the properties of shape-memory polymer composites, showing that SMPC-Fe2O3 exhibited the best thermal, mechanical, and shape-memory properties. Additionally, a microvalve actuator system was developed using SMPC-Fe2O3, showing promise for microsystem applications.
Article
Chemistry, Multidisciplinary
Jin Cui, Li Huang, Jingwei Ma, Yibin Li, Ye Yuan
Summary: This study investigates carbon shell encapsulated core-shell structured zinc ferrate sphere composites with adjustable complex permittivity and permeability. The results show that the composites exhibit considerable reflection loss and effective absorption bandwidth, while the carbon encapsulation also enhances the corrosion resistance of the material.
Article
Chemistry, Multidisciplinary
Seong-Ji Ha, Jongha Hwang, Myung-Jun Kwak, Jong-Chul Yoon, Ji-Hyun Jang
Summary: This study presents a cost-effective carbon-based novel material with high catalytic activity and good durability in Zn-air batteries. The material is prepared through a simple graphitization process and utilizes in situ growth of graphene in a 3D-metal-coordinated hydrogel. The results show greatly reduced carbon corrosion reaction (CCR) and efficient bifunctional electrocatalytic performance in an alkaline media.
Article
Polymer Science
Yuqi Xie, Jiachen Han, Tian Qin, Xuyang Ge, Xihan Wu, Lu Liu, Xubin Wu, Yunji Yi
Summary: A hybrid-integrated thermo-optic switch was designed and simulated in this study, utilizing the large thermo-optical coefficient of polymer materials. By introducing the air trench structure and optimizing the heating region's structural parameters, the power consumption was significantly reduced. This device can be applied to hybrid integration fields such as array switches and ROADMs.
Article
Computer Science, Information Systems
Shohei Zaizen, Kyohei Asami, Takashi Furukawa, Takeshi Hatta, Tsubasa Nakamura, Takashi Sakugawa, Takahisa Ueno
Summary: In this study, high-voltage switching was achieved by connecting semiconductors in series. Various measures were implemented to prevent semiconductor damage and control temperature rise. Continuous operation at different frequencies and output voltage variation were successfully realized.
Article
Chemistry, Physical
Cheng Gao, Longzhu Li, Xiaoming Yan, Ning Zhang, Junjiang Bao, Xiaopeng Zhang, Yanqiang Li
Summary: Transition metal single atom catalysts show great potential as oxygen reduction reaction catalysts for proton exchange membrane fuel cells and metal-air batteries. In this study, a strategy of encapsulating nitrogen-rich guest molecules in metal-organic framework cages was proposed to construct a high-performance cobalt single-atom catalyst. The resulting catalyst exhibits excellent ORR catalytic performance and shows high peak power density and excellent cycling stability in zinc-air batteries.
JOURNAL OF COLLOID AND INTERFACE SCIENCE
(2024)
Article
Computer Science, Information Systems
Jing-Yuan Lin, Pin-Hsien Liu, Hsuan-Yu Yueh, Yi-Feng Lin
Summary: This paper presents the design and implementation of a stepped air-gap ferrite inductor for power factor correction (PFC). The proposed method improves the load-carrying capability without increasing the volume of the inductor in peak-power-load conditions. It maintains the inductance in the rated-full-load and sustains the peak-power-load conditions with lower inductance. The proposed method can maintain the size and efficiency of the power supply and promote the power-carrying ability.
Article
Chemistry, Physical
Junling Wang, Shui Yu, Yajun Huang, Yan Zhang, Yan Quan
Summary: A metal-organic frameworks (MOFs)-based core-shell micro-nanostructure covered with curly reduced graphene oxide nanoflakes (NRGO-ZIF@CoFe) is constructed to improve the flame retardancy and mechanical performance of epoxy resin (EP). The influences of NRGO-ZIF@CoFe on flame retardancy and mechanical properties of the EP are investigated, and the results show that NRGO-ZIF@CoFe can effectively inhibit heat and smoke productions while enhancing the tensile and flexural strengths. This work provides a promising approach for the design of fire-safe and mechanical-robust polymer composites.
APPLIED SURFACE SCIENCE
(2023)
Article
Engineering, Electrical & Electronic
Satyaki Mukherjee, Yucheng Gao, Dragan Maksimovic
Summary: The article explores the use of orthogonal air-gap technique in high-frequency inductors to reduce ac resistance, demonstrating significant reduction in inductor losses compared to standard air gap designs.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2021)
Article
Engineering, Electrical & Electronic
Rafal Sylwester Kasikowski, Boguslaw Wiecek
Summary: The fringing-field phenomenon in magnetic components with an air gap can cause localized heating in windings and reduce power conversion efficiency, which can be analyzed using infrared thermography. Thermographic analysis and power loss measurements for different air gap configurations can be used to construct compact thermal models of the inductor. Splitting a single air gap into multiple individual air gaps can significantly diminish the fringing effect.
IEEE TRANSACTIONS ON POWER ELECTRONICS
(2021)
Article
Chemistry, Physical
Zheshan Zhang, Xinyue Dong, Jiabiao Chen, Zhaochao Liu, Zhansheng Gao, Xinyue Chang, Yaping Du, Chuancheng Jia, Huixia Fu, Feng Luo, Jinxiong Wu
Summary: Due to property degradation and incompatibility issues, electrical transport measurements on air-sensitive 2D materials have been challenging. A facile one-step polymer-encapsulated electrode transfer (PEET) method is developed, which allows damage-free electrodes patterning and prevents exposure to H2O/O2. The PEET method is successfully applied to investigate the electrical properties of air-sensitive SmTe2 nanosheets and can be used for other fragile ultrathin magnetic materials.
Article
Chemistry, Analytical
Tiantian Sun, Tianjiao Li, Donglai Han, Lina Liu, Heng-guo Wang
Summary: A bifunctional oxygen catalyst, Co2P/NP-CNTs, with good stability, low cost, and safety was synthesized using a one-pot method. The encapsulation structure of Co2P nanoparticles wrapped in N, P-doped carbon nanotubes provides protection, channels for electron transfer, and abundant active sites, resulting in increased electrocatalytic activity. The optimal catalyst, Co2P/NP-CNTs-800, exhibits good electrocatalytic performance for oxygen reduction and evolution reactions, as well as high open-circuit voltage, power density, and charge/discharge cycle stability when used as the air cathode in Zn-air batteries. This simple and cost-effective method provides reference value for the design and synthesis of novel bifunctional electrocatalysts in energy conversion technologies.
JOURNAL OF ELECTROANALYTICAL CHEMISTRY
(2023)
Article
Materials Science, Multidisciplinary
Luciano Borasi, Simone Frasca, Kleber Nicolet-Dit-Felix, Edoardo Charbon, Andreas Mortensen
Summary: Micron-scale shaped 2D or 2.5D structures made of silver or copper can be produced by combining silicon photolithographic etching with metal casting by pressure infiltration. This method offers excellent dimensional control, high reproducibility, compatibility with engineering metals used in microtechnology, and the potential for high production rates.
APPLIED MATERIALS TODAY
(2022)
Article
Chemistry, Applied
Jikai Wen, Xufeng Li, Yijiang Liu, Mei Yang, Bei Liu, Hongbiao Chen, Huaming Li
Summary: This study reports the facile preparation of a bifunctional electrocatalyst with remarkable ORR and OER activity by utilizing coordination interaction, and demonstrates its promising application in zinc-air batteries.
MICROPOROUS AND MESOPOROUS MATERIALS
(2022)
Article
Chemistry, Analytical
Yoontae Kim, Jin Won Kim, Jungkwun Kim, Moses Noh
SENSORS AND ACTUATORS B-CHEMICAL
(2017)
Article
Chemistry, Analytical
Sabera Fahmida Shiba, Hyeongmin Jeon, Jong-Soo Kim, Jong-Eun Kim, Jungkwun Kim
Article
Chemistry, Analytical
Jun Ying Tan, Gyuhyeong Goh, Jungkwun Kim
Article
Physics, Applied
Jun Ying Tan, Albert Kim, Jungkwun 'JK' Kim
Summary: This paper demonstrates a one-step fabrication method for fine-tuned bell-tip microneedles using UV lithography, with a combination of light diffraction and the self-aligned lens effect. The method allows for the prediction of microlens shape and microneedle morphology, ultimately achieving the fabrication of microneedle arrays.
APPLIED PHYSICS LETTERS
(2021)
Article
Engineering, Electrical & Electronic
Sabera Fahmida Shiba, Hyeongmin Jeon, Jong-Soo Kim, Jong-Eun Kim, Jungkwun Kim
Summary: An advanced UV-LED microlithography system has been introduced for 3D microfabrication, utilizing UV-LEDs, tilt-rotational mask aligner frames, and high-precision servo motors. The control software offers unique light exposure schemes for creating complex 3D microstructures, such as high aspect ratio SU-8 pillars. Successful fabrication of various 3D microstructures has shown great potential in the Bio and RF fields.
JOURNAL OF MICROELECTROMECHANICAL SYSTEMS
(2022)
Article
Chemistry, Physical
Jun Ying Tan, Yuankai Li, Faraz Chamani, Aabila Tharzeen, Punit Prakash, Balasubramaniam Natarajan, Rahul A. Sheth, Won Min Park, Albert Kim, Donghoon Yoon, Jungkwun Kim
Summary: This paper introduces the use of ultraviolet light diffraction to control the liquid-to-solid transition of photosensitive resin to define microneedle shape, investigates the impact of experimental parameters on microneedle shape, and reveals unique morphologies of microneedles. A novel inclined microneedle array was successfully fabricated by tilting the light exposure direction.
Article
Horticulture
Myungjin Lee, Jungkwun Kim, Myung-Min Oh, Jin-Hui Lee, Channa B. Rajashekar
Summary: This study investigated the effects of preharvest UV-A treatment on the nutritional quality of lettuce. The results showed that a brief exposure to UV-A increased the accumulation of protein and essential nutrients in lettuce plants.
Article
Nanoscience & Nanotechnology
Sabera Fahmida Shiba, Jun Ying Tan, Jungkwun Kim
MICRO AND NANO SYSTEMS LETTERS
(2020)
Proceedings Paper
Engineering, Electrical & Electronic
Jungkwun 'JK' Kim
2019 20TH INTERNATIONAL CONFERENCE ON SOLID-STATE SENSORS, ACTUATORS AND MICROSYSTEMS & EUROSENSORS XXXIII (TRANSDUCERS & EUROSENSORS XXXIII)
(2019)
Proceedings Paper
Engineering, Electrical & Electronic
Jungkwun 'JK' Kim, Hassan Al Thuwaini, Mohammad Almuslem
2019 IEEE 32ND INTERNATIONAL CONFERENCE ON MICRO ELECTRO MECHANICAL SYSTEMS (MEMS)
(2019)
Proceedings Paper
Engineering, Electrical & Electronic
Gyuhyeong Goh, Jun Ying Tan, Kyuseok 'KS' Lee, Yoontae Kim, Jungkwun 'JK' Kim
2018 13TH ANNUAL IEEE INTERNATIONAL CONFERENCE ON NANO/MICRO ENGINEERED AND MOLECULAR SYSTEMS (NEMS 2018)
(2018)
Proceedings Paper
Engineering, Electrical & Electronic
Jungkwun 'JK' Kim
2018 13TH ANNUAL IEEE INTERNATIONAL CONFERENCE ON NANO/MICRO ENGINEERED AND MOLECULAR SYSTEMS (NEMS 2018)
(2018)
Proceedings Paper
Engineering, Electrical & Electronic
Jungkwun 'JK' Kim, Yong-Kyu 'YK' Yoon, Mark G. Allen
2017 IEEE 12TH INTERNATIONAL CONFERENCE ON NANO/MICRO ENGINEERED AND MOLECULAR SYSTEMS (NEMS)
(2017)
Proceedings Paper
Engineering, Electrical & Electronic
Jungkwun 'JK' Kim
2017 IEEE 12TH INTERNATIONAL CONFERENCE ON NANO/MICRO ENGINEERED AND MOLECULAR SYSTEMS (NEMS)
(2017)
Article
Computer Science, Information Systems
Sayemul Islam, Xiaolei Song, Eric T. Choi, Jungkwun Kim, Haijun Liu, Albert Kim