지역정보화 지수에 의한 지역개발연계효과 분석에 관한 연구

박재홍(JaeHong Park),박철수(Chul Soo Park),박완수(Wan Soo Park) 한국지역학회 1998 지역연구 Vol.14 No.1

The purpose of this paper is to present an informatization stratagem for a balanced development around the whole country by employing Regional Information Index. In order to demonstrate the region information level by applying the factor analysis in the study, it has been divided into three catagories, such as the generation of information, the distribution of information, and the consumption of information. According to the empirical analysis between 1985 and 1995, the regional differences of the levels of the consumption and the distribution of information have been reduced gradually. On the other hand, the generation of information is significantly concentrated around Seoul Metropolitan Area. Therefore, strategic efforts providing information infrastructures as well as introducing information industries associated with informatization will guarantee a balanced development around the country.

A Non-Contact-Type RF MEMS Switch for 24-GHz Radar Applications

Jaehong Park,Shim, E.S.,Wooyeol Choi,Youngmin Kim,Youngwoo Kwon,Dong-il Cho IEEE 2009 Journal of microelectromechanical systems Vol.18 No.1

<P>This paper presents the design, fabrication, and measurement results for a novel non-contact-type radio-frequency (RF) microelectromechanical systems switch for 24-GHz radar applications. The proposed switches are free from unavoidable microwelding and stiction problems in other contact types, which in turn guarantee high reliability and long lifetime. The developed switch is a capacitive shunt type using a variation of the capacitance between the signal line and ground lines. The capacitance is precisely regulated by comb-drive actuators. This concept is simple, but the design requires a large and precise mechanical motion. In addition, for a low-loss switch structure, an air bridge with a large air gap is required. Therefore, the selective silicon-on-insulator process, based on the sacrificial bulk micromachining process, is designed for this switch fabrication. First, large insulating supports are fabricated 60 ¿m below the wafer surface, and then, the RF switch is fabricated on these insulating supports. The measured actuation voltage is 25 V, and the actuation stroke is 25 ¿m. The switching times are 8 ms in the off to the on state and 200 ¿s in the on to the off state. In the RF characteristic measurements, the insertion loss without the long coplanar waveguide line loss is 0.29 dB and the isolation is 30.1 dB at 24 GHz. The bandwidth is relatively narrow, and the isolation is 25 dB or better in the range of 23.5-29 GHz. The reliability test for the switch was performed 10<SUP>9</SUP> times with 18-mW RF power. We observed no mechanical failure or RF performance degradation. A power handling capacity of 0.9 W with a hot-switch condition was achieved.</P>

Biodegradable micro-sized discoidal polymeric particles for lung-targeted delivery system

Park, Jun Young,Park, Sanghyo,Lee, Tae Sup,Hwang, Yong Hwa,Kim, Jung Young,Kang, Won Jun,Key, Jaehong Elsevier 2019 Biomaterials Vol.218 No.-

<P><B>Abstract</B></P> <P>Various types of particle-based drug delivery systems have been explored for the treatment of pulmonary diseases; however, bio-distribution and elimination of the particles should be monitored for better understanding of their therapeutic efficacy and safety. This study aimed to characterize the biological properties of micro-sized discoidal polymeric particles (DPPs) as lung-targeted drug delivery carriers. DPPs were prepared using a top-down fabrication approach and characterized by assessing size and zeta potential. They were labeled with zirconium-89 (<SUP>89</SUP>Zr), and bio-distribution studies and PET imaging were performed for 7 days after intravenous administration. Their hydrodynamic size was 2.8 ± 6.1 μm and average zeta potential was −39.9 ± 5.39 mV. At doses of 5, 12.5, and 25 mg/kg, they showed no acute toxicity in nude mice. Desferrioxamine (DFO)-functionalized <SUP>89</SUP>Zr-labeled DPPs gave a decay-corrected radiochemical yield of 82.1 ± 0.2%. Furthermore, <SUP>89</SUP>Zr-DPPs, from chelate-free labeling methods, showed a yield of 48.5 ± 0.9%. Bio-distribution studies and PET imaging showed <SUP>89</SUP>Zr-DFO-DPPs to be mainly accumulated in the lungs and degraded within 3 d of injection. However, <SUP>89</SUP>Zr-DFO-DPPs showed significantly low uptake in the bone. Overall, our results suggested micro-sized DPPs as promising drug delivery carriers for the targeted treatment of various pulmonary diseases.</P>

Sex and Age Differences in Psychiatric Disorders among Children and Adolescents: High-Risk Students Study

JaeHong Park,YoungRong Bang,ChulKwon Kim 대한신경정신의학회 2014 PSYCHIATRY INVESTIGATION Vol.11 No.3

Objective-The aims of the present study are to investigate the rate of the psychiatric disorders in psychiatrically high-risk children and adolescents and to examine sex and age differences in the diagnosis of psychiatric disorders. Methods-The participants included students aged 6–16 from the 27 elementary and the 45 middle schools in Busan, Korea. We screened psychopathology using the Korean version of Child Behavior Checklist (K-CBCL) or the Youth Self Report (K-YSR). A total of 2,912 students were selected as high-risk students on the basis of cut-off scores (T-score ≥60) for a total behavior problem score of KCBCL/ K-YSR. Of these high-risk students, 1,985 students participated in and completed individual diagnostic interviews. Psychiatric diagnosis was assessed using a Korean version of the Kiddie-Schedule for Affective Disorders and Schizophrenia. Multivariate logistic regression analysis was conducted to examine sex and age differences of psychiatric diagnosis. Results-Based on sex, boys were more likely to have ADHD and girls were more likely to have depression. Based on age, children were more likely to have ADHD and adolescents were more likely to have affective disorder, conduct disorder, psychotic disorder, and anxiety disorders except separation anxiety disorder. Conclusion-This is the largest study to conduct face-to-face interviews with subjects and parent(s) among Korean studies in this field. The present study revealed significant differences across sex and age among specific psychiatric disorders in children and adolescents. Future population-based studies will be required to ascertain the sex- and age-related differences of psychiatric prevalence.

Synthesis of aerosol nanoparticles by spark discharge and applications

Jaehong Park,Jeong Hoon Byeon,Ki Young Yoon,Jae Hong Park,Jungho Hwang 한국입자에어로졸학회 2009 Particle and Aerosol Research Vol.5 No.3

activation with Pd and Pt aerosol nanoparticles produced by spark discharge was introduced. After annealing, the catalytically activated substrate placed into a solution for electroless silver deposition. The silver was then formed only on the activated regions of the substrate. Silver line patterns having a width of 18 μm and a height of 1 μm were created with the ability to be effectively reproduced. Antimicrobial nanoparticles such as silver were used for removal of bioaerosols. Silver nanoparticles deposited air filters such as ACF filters were evaluated by antimicrobial test.

Low-energy spin dynamics of orthoferrites AFeO₃ (A  =  Y, La, Bi)

Park, Kisoo,Sim, Hasung,Leiner, Jonathan C,Yoshida, Yoshiyuki,Jeong, Jaehong,Yano, Shin-ichiro,Gardner, Jason,Bourges, Philippe,Klicpera, Milan,Sechovský,, Vladimí,r,Boehm, Martin,Park, Je IOP 2018 Journal of physics, an Institute of Physics journa Vol.30 No.23

<P>YFeO<SUB>3</SUB> and LaFeO<SUB>3</SUB> are members of the rare-earth orthoferrites family with <I>Pbnm</I> space group. Using inelastic neutron scattering, the low-energy spin excitations have been measured around the magnetic Brillouin zone center. Splitting of magnon branches and finite magnon gaps (∼2 meV) are observed for both compounds, where the Dzyaloshinsky–Moriya interactions account for most of this gap with some additional contribution from single-ion anisotropy. We also make comparisons with multiferroic BiFeO<SUB>3</SUB> (<I>R3c</I> space group), in which similar behavior was observed. By taking into account all relevant local Dzyaloshinsky–Moriya interactions, our analysis allows for the precise determination of all experimentally observed parameters in the spin-Hamiltonian. We find that different properties of the <I>Pbnm</I> and <I>R3c</I> space group lead to the stabilization of a spin cycloid structure in the latter case but not in the former, which explains the difference in the levels of complexity of magnon band structures for the respective compounds.</P>

Efficient modeling of Lyman-alpha emitters in a large simulation box using an empirical approach.

Jaehong Park,Changbom Park,Jaehyun Lee,Juhan Kim 한국천문학회 2023 天文學會報 Vol.48 No.1

Methodology to set up nozzle-to-substrate gap for high resolution electrohydrodynamic jet printing

Park, Jaehong,Park, Ji-Woon,Nasrabadi, Ali Mohamadi,Hwang, Jungho American Institute of Physics 2016 APPLIED PHYSICS LETTERS Vol.109 No.13

Identification of Protein Phosphatase 4 Inhibitory Protein That Plays an Indispensable Role in DNA Damage Response

Park, Jaehong,Lee, Jihye,Lee, Dong-Hyun Korean Society for Molecular and Cellular Biology 2019 Molecules and cells Vol.42 No.7

Protein phosphatase 4 (PP4) is a crucial protein complex that plays an important role in DNA damage response (DDR), including DNA repair, cell cycle arrest and apoptosis. Despite the significance of PP4, the mechanism by which PP4 is regulated remains to be elucidated. Here, we identified a novel PP4 inhibitor, protein phosphatase 4 inhibitory protein (PP4IP) and elucidated its cellular functions. PP4IP-knockout cells were generated using the CRISPR/Cas9 system, and the phosphorylation status of PP4 substrates (H2AX, KAP1, and RPA2) was analyzed. Then we investigated that how PP4IP affects the cellular functions of PP4 by immunoprecipitation, immunofluorescence, and DNA double-strand break (DSB) repair assays. PP4IP interacts with PP4 complex, which is affected by DNA damage and cell cycle progression and decreases the dephosphorylational activity of PP4. Both overexpression and depletion of PP4IP impairs DSB repairs and sensitizes cells to genotoxic stress, suggesting timely inhibition of PP4 to be indispensable for cells in responding to DNA damage. Our results identify a novel inhibitor of PP4 that inhibits PP4-mediated cellular functions and establish the physiological importance of this regulation. In addition, PP4IP might be developed as potential therapeutic reagents for targeting tumors particularly with high level of PP4C expression.

A 24-GHz Low-Power RTD-Based ON–OFF Keying Oscillator With an RTD Pair Configuration

Park, Jaehong,Lee, Jooseok,Yang, Kyounghoon THE INSTITUTE OF ELECTRICAL ENGINEERS 2018 IEEE MICROWAVE AND WIRELESS COMPONENTS LETTERS Vol.28 No.6

<P>In this letter, an ON–OFF keying (OOK) oscillator that uses a resonant tunneling diode (RTD) pair configuration has been designed and fabricated. To achieve improved RF output power characteristics, the RTD pair topology was utilized in the RTD OOK oscillator design to realize an increased negative differential conductance voltage span. The fabricated IC showed high-speed switching capability of 5 Gb/s with a good phase noise characteristic of −118.17 dBc/Hz at a 1-MHz offset. The maximum RF output power was determined to be −1.76 dBm at a carrier frequency of 24.1 GHz. It consumes 12.5 mW of power, resulting in a good figure of merit value of 2.5 pJ/bit. These results demonstrate its potential as a high-performance ON–OFF mode oscillator for high-data-rate OOK transceiver systems.</P>