Design of a W-Band Seeker Antenna Employing a Dielectric-Rod Feed

Ailing Shen,Bierng-Chearl Ahn,Sang-Jin Shin,Young-Ho Cho,Kyung-Hyun Oh 한국정보기술학회 2018 한국정보기술학회논문지 Vol.16 No.2

W-band seekers find increasing applications in missile terminal homing in adverse weather conditions. W-band seekers typically employ a Cassegrain reflector antenna which requires a high-performance monopulse feed. This paper presents a design of a W-band monopulse seeker antenna fed by a new feed consisting of five dielectric rods. Compared to existing 4-horn feeds, a simple monopulse comparator can be used with the proposed feed. First an optical design of a Cassegrain antenna is presented that satisfies given specifications. Next, a feed is designed which consists of a longer dielectric rod at the center for sum pattern and four shorter dielectric rods for difference pattern placed at the top, bottom, left and right of the center dielectric rod. Finally, the dielectric-rod feed and the Cassegrain reflector are combined to realize a high-performance seeker antenna. The designed 38-wavelength diameter seeker antenna has sum pattern gain of 39.2㏈i, beamwidth of 1.79°, side-lobe level of -20㏈, and difference pattern gain of 36.4㏈i, cross-over angle of 1.04°, side-lobe level of -26㏈, and null depth of 47㏈.

Research on profile inversion pattern of polymer flooding

Ailing Zheng,Qianghan Feng,Qiansheng Wei,Dehua Liu 한국자원공학회 2018 Geosystem engineering Vol.21 No.3

Polymer flooding is becoming more common and more successful, and has made a great contribution to EOR. However, the statistical analysis of water injection profile data shows that the injection profile easily inverses during the process of single slug polymer flooding in heterogeneous reservoir. It is unfavorable for enhancing oil recovery. According to seepage mechanics theory, the cognition is determined that the injection rate distribution in high and low permeability layers depends on reservoir heterogeneity and physicochemical property of polymer. The basic reason of profile inversion lies in the different dynamic variation of resistance factors in the high and low permeability layers. In order to use existing reservoir simulation software to accurately describe the profile inversion characteristics, a processing method is submitted which is that different polymer characteristic parameters and relative permeability curves are assigned to different regions according to the distributions of reservoir characteristics during polymer flooding. Then, this processing method is used for systematically studying the profile inversion laws of different permeability ratio, polymer concentration and injecting-polymer occasion. The results show that these factors have great influence on the profile inversion. This provides a technical support for studying the profile inversion rules and corresponding improvement method.

Preparation and Characterization of Carbon Nanotubes/Carbon Fiber/Phenolic Composites on Mechanical and Thermal Conductivity Properties

Ailing Feng,Zirui Jia,Qiang Yu,Hongxia Zhang,Guanglei Wu 성균관대학교(자연과학캠퍼스) 성균나노과학기술원 2018 NANO Vol.13 No.4

The properties of fiber-matrix interface pay an important effect on the mechanical properties of carbon fiber-reinforced composites. To improve the interfacial properties in carbon fiber/phenolic resin (CF/PF) composites, CF adhered CNTs (CNTs-CF) were prepared by CVD method. The surface of treated CF and the distribution of CNTs in the interfacial region of CF were detected by scanning electron microscopy (SEM). SEM images identified 700 ℃ being the optimum growth temperature to obtain CNTs-CF, in which CNTs randomly dispersed surrounding the individual fiber surfaces. Compared to crude CF/PF composites, the tensile strength, bending strength, shear strength, impact strength, thermal conductivity at 25 C of CNTs-CF/PF composites increase by 144.5%, 59.2%, 129.0%, 75.9% and 41.7%. The improvement of mechanical properties is due to that the homogenously dispersed CNTs serve as a supplementary reinforcement to the interface and further reduce inter-laminar stress concentration. This represents an important step toward CNT-reinforced polymers with high mechanical properties.

Research on profile inversion controlling methods of multi-slug polymer alternative injection

Ailing Zheng,Dehua Liu,Yanlin Shao 한국자원공학회 2020 Geosystem engineering Vol.23 No.2

The development practice of polymer flooding shows that the injection profile easily inverses during the process of single slug polymer flooding. The low effective or ineffective circulation of abundant injecting water in high permeability layer, low producing degree of low permeability layer and large polymer volume have influenced the sweep efficiency and oil recovery of polymer flooding. In view of these questions, the alternative injection method of various viscosity polymer slugs is studied. This paper explains the theory of enhanced oil recovery of multi-slug polymer alternative injection. The experiment results show that the alternative injection of high and low viscosity polymer slugs has a better effect than single slug polymer flooding. The mobility differences between high-low permeability layers can be effectively reduced. For a multi-layer heterogeneous reservoir, there is an optimal alternative cycle. Reasonable slug size can not only inhibit dominant channel forming in high permeability layer but also can effectively produce low permeability layer and control profile inversion to a certain extent. This provides a technical support for studying the controlling methods of profile inversion.

Production of Single-chain Fv Antibodies against Melamine from a Rabbit Phage Display Library for the Development of a Melamine Immunoassay

Ailing Huang,Tun Lu 한국식품과학회 2011 Food Science and Biotechnology Vol.20 No.6

A rabbit phage display library of single chain Fv (scFv) antibodies was constructed to screen specific scFv antibodies against melamine. Rabbits were immunized with melamine immunogens prepared via glutaraldehyde method. Two recombinant scFv antibodies with high specificity for melamine, termed A9 and B4, were isolated via library panning. SDS-PAGE analysis showed that the soluble A9-scFv and B4-scFv antibodies were expressed successfully and the scFvs showed good sensitivity with an IC50 of 12.64 and 10.32 μM to melamine, respectively. The cross-reactivity of 2 scFv antibodies with cyanuric acid and chloromycetin were below 1%. The high similarity of 2scFv nucleotide sequences indicated that they may originate from 1 B cell clone that had undergone somatic diversification. As a consequence, the conjugation synthesis was successful and the selected scFvs could be used for sensitive detection of melamine in foods and feeds by immunoassay.

Design of a 94-GHz Square Waveguide Combiner for Monopulse Applications

Ailing Shen · Ahn, Bierng Chearl 충북대학교 컴퓨터 정보통신 연구소 2017 컴퓨터정보통신연구 Vol.25 No.1

본문참고

중국인 유학생의 문화적응 유형별 사회적 지지와 진로장벽이 대학생활 적응에 미치는 영향

Jin Ailing,오인수 한국상담학회 2017 상담학연구 Vol.18 No.4

The current study examined factors influencing on Chinese international students’ adjustment in terms of social support and career barrier, because the number of Chinese international students is increasing and their maladjustment issues are emerging. Especially, the study applied the cultural adaptation model to explore differentiating factors affecting college adjustment according to the type of cultural adaptation. The relationships of Chinese international student’s social support, career barrier and college adjustment were investigated in terms of acculturation types based on survey completed by 331 Chinese international students. The results are as follows: Firstly, according to the acculturation types, significant differences of college adjustment and social support were found, but no difference in career barrier was identified. Secondly, after observation the effects of sub-types of career barrier and social support on college adjustment, according to the acculturation types of Chinese students, it was identified that career on college adjustment have significant effect in all types. career barrier influenced on college adjustment regardless of the acculturation types, On the other hand, the influence of sub-factors in social support on college adjustment was different in terms of the acculturation types. As for integration type, Korean peer support was found as a significant factor, while Korean instructor’s support was found as a significant factor for both assimilation and separation type. Social support was found as a non-significant factor among the marginalized type. Effective educational and counseling intervention to improve Chinese international student’s college adjustment were discussed based on the results. 본 연구는 중국인 유학생이 급증하고 있는 가운데 이들의 대학 부적응 문제가 이슈가 되고 있는 상황에서 대학생활의 적응에 영향을 미치는 요인을 사회적 지지와 진로장벽의 관점에서 분석하였다. 특히 문화적응모형을 적용하여 문화적응의 유형에 따라 대학생활에 영향을 미치는 차별적 변인을 탐색하였다. 이를 위하여 중국인 유학생 331명을 대상으로 실시한 설문조사를 바탕으로 문화적응 유형에 따른 중국인 유학생의 사회적 지지, 진로장벽, 대학생활 적응의 관계를 살펴보았다. 첫째, 중국인 유학생의 문화적응 유형에 따라 진로장벽은 유의한 차이가 없었지만 대학생활 적응과 사회적 지지에는 유의미한 차이가 확인되었다. 둘째, 중국인 유학생의 문화적응 유형에 따른 진로장벽 및 사회적 지지의 하위 유형이 대학생활 적응에 미치는 영향을 살펴본 결과 모든 유형에서 진로장벽이 대학생활 적응에 유의미한 영향을 미치는 것으로 확인되었다. 반면 사회적 지지의 하위요인이 대학생활 적응에 미치는 영향은 문화적응 유형에 따라 다르게 나타났다. 통합유형은 한국 친구의 지지가 유의미한 영향을 미친 반면, 동화 및 분리유형의 경우에는 한국 교강사의 지자가 유의미한 영향을 미치는 것으로 확인되었다. 그리고 주변인 유형의 경우에는 사회적 지지가 유의미한 영향을 미치지 않는 것으로 나타났다. 본 연구의 결과를 바탕으로 중국인 유학생의 대학생활 적응을 향상시키기 위한 교육 및 상담적 방안에 대해 논의하였다.

Deep learning-based smith predictor design for a remote grasping control system

김동언,Ailing Li,Mai-Ngoc Dau,Hyun Hee Kim,Wan-Young Chung 대한기계학회 2022 JOURNAL OF MECHANICAL SCIENCE AND TECHNOLOGY Vol.36 No.5

In this study, a robotic hand control system was designed based on data gloves, aiming to provide more intuitive control and improved operational performance for a remote robotic hand. Compensation measures were proposed for the time lag effect on the remotecontrol system to address the input and feedback time delays of the remote robot system. A Smith predictor structure was modified by replacing the linear estimator with a recurrent neural network. A convolutional neural network was applied to the long short-term memory (LSTM) model, as it had a better convergence time and learning performance than the multi-layer perceptron model during training. The experimental results demonstrate that the control effect of this scheme is approximately 0.5 s faster than the normal Smith predictive control, proving its effectiveness.

Detecting Fraudulent Financial Information of a Company Using Hidden Markov Model

Ruicheng Yang,Ailing Zuo,Qing Shen 보안공학연구지원센터 2016 International Journal of Security and Its Applicat Vol.10 No.9

Using Hidden Markov Model (HMM), this paper detects some fraudulent financial information of a company. The research index MBSPM (Main Business Service Profit Margin) ratio of company is used to test the effectiveness of HMM. Due to the shortage of the fraudulent data, based on the MBSPM index data we generate the artificial fraudulent financial information data by Poisson process and Uniform distribution, that is, we use the Poisson process to simulate the arrival times of the fraudulent financial information and the Uniform distribution to simulate their fraudulent sizes. By embedding the artificial fraudulent financial information data into the non-fraudulent MBSPM data, we form the sample data series. Applying Henderson filter method, we derive the research sample data by getting rid of the sample data series trends. We do some experiments to test the validity of HMM for detecting the fraudulent financial information, and further make some comparisons with other detecting techniques: logistic regression and ANNs. The detected results show that the HMM approach can significantly improve the identification accuracy.

Phase transitions and electrical properties of (Na0.5K0.5)NbO3-Bi(Sc0.5Fe0.5)O3 lead-free piezoelectric ceramics

Hongfu Wang,Ailing Ding 한양대학교 세라믹연구소 2010 Journal of Ceramic Processing Research Vol.11 No.1

Lead-free ceramics (1-x)(Na0.5K0.5)NbO3-xBi(Sc0.5Fe0.5)O3 (KNN-BSF, x = 0−0.08) were synthesized by conventional solid-state sintering. A morphotropic phase boundary (MPB) is formed in the ceramics near x = 0.01−0.02 at room temperature by Xray analysis. Dielectric temperature spectra indicate the existence of two dielectric anomalous peaks, which correspond to orthorhombic-tetragonal (TOT) and tetragonal-cubic (TC) transitions. The ceramic with x = 0.0125 near the MPB exhibits the following optimal electrical properties: Pr = 33.9 μC/cm2, Ec = 18.1 kV/cm, d33 = 255 pC/N, kp = 0.44, and Tc = 372 oC.