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Frequency-Dependent Transmission Line Modeling Technique for Steady-State Harmonic Impedance Scanning 정상상태 고조파 임피던스 스캐닝을 위한 주파수 종속 송전선로 모델링 기법
No full textThis paper focuses on the analysis of frequency-dependent characteristics in transmission lines and their impact on harmonic impedance. Transmission line modeling is conducted in the time domain, incorporating existing frequency-dependent parameters, to evaluate the minimum requirements for accurate harmonic impedance modeling. The results show that these frequency-dependent characteristics significantly influence both the resonance frequency and magnitude of harmonic impedance. Furthermore, it is observed that sufficient approximation can be achieved even when the effects of ground return are disregarded.N
DNA Barcoding Reveals Taxonomic Insights Into Pest Species of Leafhoppers (Hemiptera: Cicadellidae) on Fruit Trees in South Korea
No full textSevere leafhopper pests infesting fruit trees (apricot, grape, peach, persimmon and plum) in South Korea were investigated. DNA barcoding using mitochondrial cytochrome c oxidase (COI) sequences identified four Typhlocybinae species: Arboridia kakogawana and Arboridia maculifrons on grape, Singapora shinshana on Prunus trees and Zorka sp. on persimmon, spanning both nymphal and adult life stages. Notably, DNA barcoding revealed phylogenetically relevant colour variation among adult specimens of the grape pest, A. kakogawana. This study presents, for the first time, live nymphal and adult photographs alongside neighbour-joining trees, host plant associations and updated DNA barcode sequences for these Korean leafhoppers, which have not previously been included in global datasets.N
The Impact of Post-Traumatic Stress on Social Adaptation among Disaster Victims: The Moderating Role of Perception of Disaster Psychological Recovery Support
No full text재난 피해자의 외상 후 스트레스는 사회적응에 부정적인 영향을 미치며, 충분한 재난심리회복지원 제공이 이를 완화할 수 있으나, 이들 간의 구체적 관계를 다룬 연구는 부족하다. 본 연구는 외상 후 스트레스가 재난 피해자의 사회적응에 미치는 영향을 파악하고, 이 관계에서 재난심리회복지원에 대한 인식의 조절효과를 검증하고자 하였다. 이를 위해 제4차 재난 피해자 삶의 변화 추적조사(2019)에 참여한 19세 이상의 재난 피해자 2,300명의 응답을 활용하여 위계적 회귀분석을 수행하였다. 재난심리회복지원에 대한 인식은 제공받은 재난심리회복지원의 충분성에 대한 5점 척도 응답으로 측정되었다. 분석 결과, 재난 피해자의 외상 후 스트레스가 높을수록 사회적응이 낮아졌으며, 재난심리회복지원에 대한 인식이 이 관계를 조절하는 것으로 나타났다. 이는 재난 피해자의 외상 후 스트레스가 높은 상황에서 충분한 재난심리회복지원이 제공되는 것이 이들의 사회적응을 돕는 데 중요함을 시사한다. 본 연구는 이러한 결과를 바탕으로 재난 피해자의 사회적응을 강화하기 위한 재난심리회복지원 정책의 발전 방향을 논의하였다.N
A new species of Stenosternum (Mesostigmata: Antennophorina: Hoplomegistidae), the first trigynaspid mite from Korea, including the description of immature stages
No full textHoplomegistidae are large trigynaspid mites found as adults on passalid beetles in Africa, Southeast Asia, and Central and South America. The family comprises ten species, of which only two species occur in Southeast Asia, both described recently from the Southern part of China. Here, we describe a new species, Stenosternum leptaulax n. sp., found on Leptaulax koreanus (Coleoptera: Passalidae) from the Republic of Korea. This is the first report of a trigynaspid mite from Korea. Our description also includes the larva, protonymph and deutonymph, representing the first description of the immatures for this family.N
Subjective Age in Korean Middle-Aged Adults: Differences by Family and Social Network Characteristics and Implications for Psychological Well-Being
No full text노화에 대한 인식이 노인의 신체적 건강 및 웰빙과 밀접하게 관련되어 있다는 연구 결과는 지속적으로 보고되어 왔다. 반면, 중년기 개인이 가족 및 사회적 경험을 통해 노화에 대한 인식을 어떻게 형성하는지는 상대적으로 잘 알려져 있지 않다. 이에 본 연구는 우리나라 50대 중장년기 성인이 본인의 주관적 연령을 어떻게 인식하고 있으며, 가족 및 사회관계망 특성에 따라 주관적 연령 인식에 차이가 있는지, 그리고 주관적 연령 인식이 심리적 복지감(삶의 만족도와 우울 증상)과 어떻게 관련되어 있는지 살펴보았다. 이를 위하여 「한국 베이비부머 패널 연구」의 3차년도(2014) 조사참여자(51-59세) 4,034명이 본인의 네 가지 주관적 연령(체감 연령, 외모 연령, 행동 연령, 관심사 연령)을 응답한 자료를 분석하였다. 주요 분석 결과는 다음과 같다. 첫째, 대부분의 응답자(73-79%)는 네 가지 주관적 연령을 본인의 실제 연령대인 50대로 인식하고 있었으며, 주관적 연령을 실제보다 어린 연령대로 인식하는 응답자들(16-22%)은 실제보다 높은 연령대로 인식하는 응답자들(5-6%)보다 많았다. 둘째, 가족 특성 중 배우자 유무와 자녀 수에 따라 응답자의 주관적 연령 인식은 다르게 나타났다. 즉, 배우자가 있는 응답자의 경우, 체감 연령을 실제보다 낮은 연령대로 인식하는 비율이 적었고, 행동 연령과 관심사 연령은 실제보다 높은 연령대로 인식하는 비율이 적었다. 자녀 수가 많은 응답자들은 자신의 외모 연령, 행동 연령, 관심사 연령을 실제보다 낮은 연령대로 인식하는 비율이 적었다. 셋째, 주관적 연령 인식은 응답자의 사회관계망 특성에 따라서도 유의한 차이를 보였다. 즉, 친구 및 지인과 자주 만나는 응답자들은 본인을 실제보다 낮은 연령대로 인식하는 비율이 적은 반면, 친구 및 지인과 비대면으로 자주 연락하는 응답자들은 본인을 실제보다 낮은 연령대로 인식하는 비율이 높았다. 또한, 많은 사회모임에 참여하는 응답자들은 본인의 실제 연령대보다 낮은 연령대로 인식하는 비율은 높고, 높은 연령대로 인식하는 비율은 낮았다. 넷째, 본인의 외모 연령과 관심사 연령을 실제 연령대보다 낮게 인식하거나 높게 인식하는 두 경우 모두 삶의 만족도가 유의하게 낮았고, 체감 연령은 실제보다 높은 연령대로 인식하는 경우만 삶의 만족도가 유의하게 낮았다. 또한, 본인의 관심사 연령을 실제 연령대보다 높게 인식하는 경우 우울 증상이 유의하게 많은 것으로 나타났다. 본 연구의 결과는 한국 중장년기 성인의 주관적 연령 인식에서 가족 및 사회적 관계 맥락이 갖는 중요성을 확인함과 동시에, 주관적 연령의 영역에 따라 심리적 복지감에 미치는 영향이 다를 수 있음을 시사한다.N
380-GHz Third Harmonic Signal Generation Using Differentially Pumped Varactors in a CMOS Voltage Controlled Oscillator
No full textAn LC-VCO incorporating differentially pumped varactors for 3rd order harmonic generation is demonstrated in a 65-nm bulk CMOS process with an fmax of 250 GHz. The differentially pumped N-type Accumulation mode MOS varactor pair acting as a symmetric varactor serves as a frequency tuning element, as well as the non-linear reactive elements for harmonic generation. The measurements show that the circuit has a peak radiated power of -15.2 dBm with a frequency tuning range between 361.4 to 383.3 GHz or 5.9 %, and a peak DC-THz efficiency of 0.102 %. Among the CMOS oscillator signal generators with an on-chip antenna and output frequency greater than 300 GHz, the circuit exhibits the state-of-the-art DC-THz efficiency.N
Greater Influence of Density on the Electrical Properties of an Organic Semiconductor Glass Compared to Molecular Orientation
No full textPhysical vapor deposition is widely used in the fabrication of organic light-emitting diodes and has the potential to adjust the density and orientation through substrate temperature control, which may lead to enhanced electrical performance. However, it is unclear whether this enhanced property is because of the horizontal molecular orientation or the increased density. The effects of the density and orientation on the electrical properties of a potential electron transport material, (3-dibenzo[c,h]acridin-7-yl)phenyl)diphenylphosphine oxide (TPPO-dibenzacridine), were investigated. According to the gyration tensor analysis, TPPO-dibenzacridine resembled an oblate ellipsoid. Furthermore, these films exhibited the highest density when prepared at a substrate temperature of 87.5% of the glass transition temperature with an increase in density of approximately 1.5%. Variable angle spectroscopic ellipsometry measurements confirmed that the transition dipole moment direction of the dibenzacridine moiety, which is involved in the electrical properties, remained isotropic at this temperature. Although horizontal orientations are known to optimize their pi-pi overlap and improve the electrical properties, the lowest driving voltage was observed under these conditions, which led to the conclusion that the enhanced electrical properties of TPPO-dibenzacridine are greatly influenced by the increased density rather than by the molecular orientation.N
Sea spray effects on typhoon prediction in the Yellow and East China Seas: case studies using a coupled atmosphere-ocean-wave model for Lingling (2019) and Maysak (2020)
No full textThis study investigates the impact of sea spray parameterization on typhoon prediction in the Yellow and East China Seas (YECS) region. Using an air-sea-wave coupled model, we evaluate changes due to sea spray effects in the simulated intensity and structure of Typhoons Lingling (2019) and Maysak (2020). Enabling sea spray effect enhances surface turbulent heat fluxes considerably around the typhoon centers (74% increase for Lingling, 92% for Maysak), leading to a better representation of typhoon intensification phases. Analysis of thermodynamic processes reveals that sea spray-induced warming emerges before rapid intensification, with enhanced temperature and moisture profiles throughout the troposphere supporting stronger secondary circulation. As a result, key aspects of typhoon prediction exhibit significant improvements: root-mean-squared errors decreased by 63% in minimum central pressure and 60% for maximum wind speed in the case of Maysak. The results demonstrate that sea spray effects are strongly modulated by sub-surface ocean conditions, with a greater surface heat flux enhancement for Maysak that moved along warmer Kuroshio and Tsushima currents than for Lingling which passed over Yellow Sea Bottom Cold Water. Our findings demonstrate the significant potential to improve typhoon predictions in the YECS region by incorporating sea spray effects.Y
Multi-Modal Grounded Planning and Efficient Replanning For Learning Embodied Agents with a Few Examples
No full textLearning a perception and reasoning module for robotic assistants to plan steps to perform complex tasks based on natural language instructions often requires large free-form language annotations, especially for short high-level instructions. To reduce the cost of annotation, large language models (LLMs) are used as a planner with few data. However, when elaborating the steps, even the state-of-the-art planner that uses LLMs mostly relies on linguistic common sense, often neglecting the status of the environment at command reception, resulting in inappropriate plans. To generate plans grounded in the environment, we propose FLARE (FEW-SHOT LANGUAGE WITH ENVIRONMENTAL ADAPTIVE REPLANNING EMBODIED AGENT), which improves task planning using both language command and environmental perception. As language instructions often contain ambiguities or incorrect expressions, we additionally propose to correct the mistakes using visual cues from the agent. The proposed scheme allows us to use a few language pairs thanks to the visual cues and outperforms state-of-the-art approaches. Our code and the dataset are publicly available to facilitate further research.N
Utilizing deep learning-based causal inference to explore vancomycin's impact on continuous kidney replacement therapy necessity in blood culture-positive intensive care unit patients
No full textPatients with positive blood cultures in the intensive care unit (ICU) are at high risk for septic acute kidney injury requiring continuous kidney replacement therapy (CKRT), especially when treated with vancomycin. This study developed a machine learning model to predict CKRT and examined vancomycin's impact using deep learning-based causal inference. We analyzed ICU patients with positive blood cultures, utilizing the Medical Information Mart for Intensive Care III data set. The primary outcome was defined as the initiation of CKRT during the ICU stay. The machine learning models were developed to predict the outcome. The deep learning-based causal inference model was utilized to quantitatively demonstrate the impact of vancomycin on the probability of CKRT initiation. Logistic regression was performed to analyze the relationship between the variables and the susceptibility of vancomycin. A total of 1,318 patients were included in the analysis, with 41 requiring CKRT. The Random Forest and Light Gradient Boosting Machine exhibited the best performance, with Area Under Curve of Receiver Operating Characteristic Curve values of 0.905 and 0.886, respectively. The deep learning-based causal inference model demonstrated an average 7.7% increase in the probability of CKRT occurrence when administrating vancomycin in total data set. Additionally, that younger age, lower diastolic blood pressure, higher heart rate, higher baseline creatinine, and lower bicarbonate levels sensitized the probability of CKRT application in response to vancomycin treatment. Deep learning-based causal inference models showed that vancomycin administration increases CKRT risk, identifying specific patient characteristics associated with higher susceptibility.Y