• The Journal of Korean Institute of Electromagnetic Engineering and Science
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• v.20 no.12
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• pp.1233-1242
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• 2009

In this paper, a Base Station Antenna(BSA) utilizing Artificial Magnetic Conductor(AMC) as reflector instead of common conductive plate to improve radiation characteristics and achieve low-profile is proposed. In the case of the conventional BSA on conductive surface which acts as a reflector, a secondary radiation is caused at the corner of the conductive surface, and it increases the back-lobe of the antenna, resulting in deteriorating the radiation characteristic of the conventional BSA. However, using the AMC, the back-lobe of the BSA can be largely reduced by the surface wave suppression. And the Side-Lobe Level(SLL) is also improved, resulting in preventing the service area overlapped. Furthermore, due to the $0^{\circ}$ reflection phase on AMC, the profile of the BSA can be also reduced.

• Journal of Institute of Control, Robotics and Systems
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• v.21 no.9
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• pp.888-897
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• 2015

A flight capability to take a terrain following flight near the ground is required to reduce the probability that a fighter aircraft can be detected by foe's radar fence in the battlefield. The success rate for mission flight has increased by adopting TFS (Terrain Following System) to enable the modern advanced fighter to fly safely near the ground at the low altitude. This system has applied to the state-of-the-art fighter and bomber, such as B-1, F-111, F-16 E/F and F-15, since the research begins from 1960's. In this paper, the terrain following system and GCAS (Ground Collision Avoidance System) was developed, based on a digital database with UTAS's TERPRROM (TERrain PROfile Matching) equipment. This system calculates the relative location of the aircraft in the terrain database by using the aircraft status information provided by the radar altimeter and the INS (Inertial Navigation System), based on the digital terrain database loaded previously in the DTC (Data Transfer Cartridge), and figures out terrain features around. And, the system is a manual terrain following system which makes a steering command cue refer to flight path marker, on the HUD (Head Up Display), for vertical acceleration essential for terrain following flight and enables a pilot to follow it. The cue is based on the recognized terrain features and TCH (Target Clearance Height) set by a pilot in advance. The developed terrain following system was verified in the real-time pilot evaluation in FA-50 HQS (Handling Quality Simulator) environment.

• Asian-Australasian Journal of Animal Sciences
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• v.21 no.11
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• pp.1585-1591
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• 2008

The aim of the present work was to monitor metabolic and hormonal profiles in newborn kids, born from dams fed diets with low or high levels of energy requirements. Starting from the last month of pregnancy, 14 goats were randomly allocated to two groups: Group LD (low diet) and Group HD (high diet) that received a diet that covered 80% and 140% of their energy requirement, respectively. At delivery, the kids were weighed and a blood sample was taken before they suckled colostrum (Time 0) and 1, 2, 3, 12 and 24 h after they started suckling. Plasma insulin, IGF-I, glucose, fT3 and fT4 concentrations were not influenced by the dietary treatments, but a significant effect of time was observed as they progressively increased during the first 12 h of life. Plasma cholesterol, triglyceride, albumin, globulin and total protein plasma concentrations were significantly higher in Group HD than those of Group LD. In Group HD, cortisol concentrations were significantly lower than those of Group LD. Positive correlations were observed between LW and IGF-I (r = 0.71; p<0.05), plasma insulin and glucose (r = 0.79; p<0.05) and total protein and globulin concentrations (r = 0.97; p<0.001). Our results show that perinatal nutrition affects newborn goat kids' metabolic and hormonal profile.

• International Journal of Fluid Machinery and Systems
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• v.4 no.1
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• pp.133-139
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• 2011

In this paper, Based on Two-dimensional Flow Theory, adopting quasi-orthogonal method and point-by-point integration method to design the impeller of the low specific speed centrifugal pump by code, and using RANS (Reynolds Averaged N-S) Equation with a standard k-${\varepsilon}$ two-equation turbulence model and log-law wall function to solve 3D turbulent flow field in the impeller of the low specific speed pump. An analysis of the influences of the blade profile on velocity distributions, pressure distributions and pump performance and the investigation of the flow regulation pattern in the impeller of the centrifugal pump are presented. And the result shows that this method can be used as a new way in low speed centrifugal pump impeller design.

• Proceedings of the Korean Institute of Surface Engineering Conference
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• 2003.05a
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• pp.56-56
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• 2003

플라즈마 식각에서 물리적 손상과 전기적 손상은 차세대 Nanoscale 소자와 Deep - Submicron 반도체공정에서 해결되어야 할 가장 큰 문제 중 하나이다. 이 중 전기적인 손상을 줄이기 위한 몇 가지 무손상 공정이 제시되고 있으며, 그러한 기술 중의 하나가 이온빔의 Low Angle Forward Reflection을 이용한 식각방법이다. Low Angle Forward Reflection방법은 이온소오스로부터 발생시킨 이온을 Low Angle 에서 Reflection-시켜 이온빔을 중성화되도록 하는 방법으로, 이전 연구를 통해 Reflection시 입사각이 5도일 경우 대부분의 이온들이 중성화되는 결과를 얻었다. 또한, 실험에 사용된 $SF_6,{\;}NF_3,{\;}CF_4$와 같은 모든 가스종에서 유사한 값의 중성화 정도를 관찰할 수 있었으며, 이러한 가스를 이용하여 $Si0_2$ 식각시 Vertical한 Profile 결과를 얻었다. 본 연구에서는 기존 Grid 장치에서 이온소오스 부분에 Low Angle Forward Reflected Neutral Beam을 위한 판형 Reflector를 부착하였으며, 이에 따라 중성빔의 Flux가 크게 향상되며 Beam의 직진성을 향상시킬 수 있었다. 또한, F계열 가스를 이용한 실험을 통해 $Si0_2$ 식각율과 식각특성 면에서 향상된 실험결과를 얻을 수 있었다.

• Journal of electromagnetic engineering and science
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• v.16 no.3
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• pp.194-197
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• 2016

An eight-element compact low-profile multi-input multi-output (MIMO) antenna is proposed for wireless local area network (WLAN) mobile applications. The proposed antenna consists of eight inverted-F antennas with an isolation-enhanced structure. By inserting the isolation-enhanced structure between the antenna elements, the slot and capacitor pair generates additional resonant frequency and decreases mutual coupling between the antenna elements. The overall size of the proposed antenna is only $33mm{\times}33mm$, which is integrated into an area of just $0.5{\lambda}{\times}0.5{\lambda}$. The proposed antenna meets 5-GHz WLAN standards with an operation bandwidth of 4.86 - 5.27 GHz and achieves an isolation of approximately 30 dB at 5 GHz. The simulated and measured results for the proposed antenna are presented and compared.

• The Journal of The Korea Institute of Intelligent Transport Systems
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• v.6 no.2
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• pp.113-118
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• 2007

KPCS internal antenna in this paper, is designed and fabricated using the theory based on the folded monopole antenna. I propose folded monopole internal antenna which has high gain low profile structure with easy installation into the handset of mobile phone. Design frequency is 1.8 GHz that is a center frequency of Korea PCS frequency band, and the impedance variances due to change of antenna structure as a length and width are simulated. Measurements show that input VSWR range under 2:1 is 1.72 - 1.88 GHz, and radiated H-plane pattern is omnidirectional under passive state. Active sensitivities and output power of phone applied antenna are $-105\;{\sim}\;-108\;dBm$ and $22.5\;{\sim}\;23.6\;dBm$ max., respectively.

• Advances in Traditional Medicine
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• v.8 no.3
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• pp.311-315
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• 2008

The objective of the study was to investigate the antihyperlipidemic activity of alcoholic extract of Pongamia pinnata Linn. (PPAE) leaves in rats fed with high fat diet (HFD). PPAE was administered orally in the divided doses of 250 and 500 mg/kg/day for 30 days in HFD fed rats. Body weights were observed and the analysis of serum lipid profile was carried out on day 30. Marked decrease in the body weight, total cholesterol (TC), triglycerides (TG), low density lipoprotein (LDL) and very low density lipoprotein (VLDL) whereas significant increase in the levels of high density lipoprotein (HDL) were observed after treatment with PPAE. However, PPAE in a dose of 250 mg/kg did not show significant (P < 0.05) increase in HDL levels. The PPAE also lowered TC: HDL-c and LDL: HDL-c ratios significantly suggesting it's antihyperlipidemic and cardioprotective potential. The present work reveals that PPAE at the dose of 500 mg/kg/day exhibited significant (P < 0.01) antihyperlipidemic effects.

• KSII Transactions on Internet and Information Systems (TIIS)
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• v.5 no.11
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• pp.2016-2034
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• 2011

Ubiquitous Healthcare (u-Healthcare) is the intelligent delivery of healthcare services to users anytime and anywhere. To provide robust healthcare services, recognition of patient daily life activities is required. Context information in combination with user real-time daily life activities can help in the provision of more personalized services, service suggestions, and changes in system behavior based on user profile for better healthcare services. In this paper, we focus on the intelligent manipulation of activities using the Context-aware Activity Manipulation Engine (CAME) core of the Human Activity Recognition Engine (HARE). The activities are recognized using video-based, wearable sensor-based, and location-based activity recognition engines. An ontology-based activity fusion with subject profile information for personalized system response is achieved. CAME receives real-time low level activities and infers higher level activities, situation analysis, personalized service suggestions, and makes appropriate decisions. A two-phase filtering technique is applied for intelligent processing of information (represented in ontology) and making appropriate decisions based on rules (incorporating expert knowledge). The experimental results for intelligent processing of activity information showed relatively better accuracy. Moreover, CAME is extended with activity filters and T-Box inference that resulted in better accuracy and response time in comparison to initial results of CAME.

• Journal of Korean Physical Therapy Science
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• v.17 no.1_2
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• pp.11-21
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• 2010

Background: This study was undertaken to evaluate how gender differences affect the sensory processing by the Adolescent/Adult Sensory Profile(ASP) which evaluates the behavioral responses of adults to everyday sensory experiences. Methods: The study period lasted one month which was June 2009, and the study subjects were 325(three hundred twenty five) people who were healthy and reside in Chungcheong province including Daejeon. Detailed information about the study was explained to the study group and the ASP questionnaires were drawn up by them personally. Results: On average, the study group scores similarly in low registration, sensation seeking, sensory sensitivity, and sensation avoiding. According to the sensory processing abilities by gender, the group obtained scores indicating performance similar to most people in low registration, sensation seeking, and sensory sensitivity, except for sensation avoiding. Furthermore, in the taste/smell processing of "I only eat familiar foods", sensation avoiding score was higher in females than males, and in the activity level of "I find time to get away from my busy life and spend time by myself", males' sensation avoiding scored higher than females. Conclusion: In the study of differences of sensory processing abilities of adults by gender using the ASP, gender differences were revealed in the category of sensation avoiding.