• Title/Summary/Keyword: frequency-based method

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Slat Noise Source Modeling of Multi-element Airfoil in High-lift Configuration

  • Hwang, Seung Tae;Han, Chang Kyun;Im, Yong Taek;Kim, Jong Rok;Bae, Youngmin;Moon, Young J.
    • International Journal of Aeronautical and Space Sciences
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    • v.18 no.2
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    • pp.197-205
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    • 2017
  • We investigate the slat noise generation mechanism by using large-eddy simulation (LES) and simple source modeling based on linearized Euler equations. An incompressible LES of an MD 30P30N three-element airfoil in the high-lift configuration is conducted at $Re_c=1.7{\times}10^6$. Using the total derivative of the hydrodynamic pressure (DP/Dt) acquired from the incompressible LES, representative noise sources in the slat cove region are characterized in terms of simple sources such as frequency-specific monopoles and dipoles. Acoustic radiation around the 30P30N multi-element airfoil is effectively computed using the Brinkman penalization method incorporated with the linearized Euler equation. The directivity pattern of $p^{\prime}_{rms}$ at $r=20c_{slat}$ in the multiple sources is closely compared to that obtained by the application of the LES/Ffowcs-Williams and Hawking's methods to the entire flow field. The power spectrum of p' at ${\theta}=290^{\circ}$ is in good agreement with the data reported in BANC-III, especially the broadband part of the spectrum with a decaying slope ${\propto}f^{-3}$.

Analysis of Empathy-Related Research Trends in Social Selfare Studies (사회복지학문 분야에서 공감 관련 연구동향 분석)

  • Kweon, Sin-Jung;Kim, Kangmin
    • The Journal of the Korea Contents Association
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    • v.20 no.10
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    • pp.544-553
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    • 2020
  • This study was intended to examine the academic role of social welfare by analysis the trends of empathic research in the field of social welfare studies in Korea, and to explore the direction and tasks to move forward. For this purpose, technical analysis and language network analysis were performed based on the category system and the frequency of simultaneous language presentation by selecting academic papers related to empathy in the field of social welfare studies in Korea from 2000 to June 2020. According to the analysis, the number of empathic studies in the social welfare field has increased steadily since 2000, and the number of studies in the last three years has increased significantly, and the research field has been mainly in the "social welfare general" category. In terms of research, the most common research was related to empathy and the relationship between other variables, while quantitative research was the most important method used in the research. As empathic-related research increase in social welfare studies, such research results require efforts such as expansion of research field and research contents and attempts of various research methods.

The Study on Menu Patterns in Korean Rural Areas (I) - Analysis of Major Menu Pattern - (우리나라 농촌지역의 메뉴패턴에 관한 연구 (I) -주요 메뉴패턴 분석 -)

  • 문현경;이삼순;김정윤;박송이;한귀정;유춘희;백희영;정금주
    • Journal of Nutrition and Health
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    • v.34 no.8
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    • pp.936-945
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    • 2001
  • This study was conducted to investigate the menu patterns consumed frequently in 5 Korean rural areas for all seasons, using 24-hour recall method with 1,185 subjects. The purpose of this study was to suggest the menu pattern in rural areas for the basis data of the nutrition education program and nutrition intervention project. The result were following : most frequently used menu patterns by the number of side dish were rice + soup + kimchi + 1 side dish> rice + soup + kimchi + 2 side dish> rice + soup + kimchi > rice + stew + kimchi + 1 side dish in the order. Most frequently used menu patterns by the kind of side dish were rice + soup + kimchi > rice + stew + kimch > rice + kimchi> noodle + kimchi in the order. In menu patterns showed higher frequency, Nutrient Adequacy Ratio(NAR) of all nutrients except Ca and Vit A was over 0.7. The Mean Adequacy Ratio (MAR) of rice + soup(or stew) + kimchi + 2(or 3) side dish was 0.76∼0.82. The number of dishes consumed in winter was the highest. The menu had traditional menu pattern based on cooked rice, Korean soup and kimchi in Korean rural areas. With these results, we can conclude that nutrient balances from the menu pattern can be improved, if the composition of main dish and side dish are adequate . For the nutrition program in the community menu patterns should be examined carefully. The result from this study can be used as basic data for nutrition education programs in Korean rural areas.

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Familial Breast Cancer Registry Program in Patients Referred to the Cancer Institute of Iran

  • Sabokbar, Tayebeh;Khajeh, Elias;Taghdiri, Foad;Peyghambari, Vahideh;Shirkoohi, Reza
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.6
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    • pp.2675-2679
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    • 2012
  • Introduction: Annually a considerable number of people die because of breast cancer, a common disease among women also in Iran. Identifying risk factors and susceptible people can lead to prevention or at least early diagnosis. Among susceptibility risks, 5-10% of patients have a family history predisposing factor which can influence the risk of incidence among the family. Having a registry program can be a more practical way to screen high risk families for preventive planning. Method: Based on inclusion criteria, a questionnaire was prepared and after a pilot study on a small number of patients, actual data were collected on 400 patients and processed in SPSS 16.0. Results: Totally, 28.2%of the patients were younger than 40 years old and 36.8% had the included criteria for familial breast cancer (FBC). 102 patient's samples could be compared for receptor presentation. Similar to other studies, the number of triple negative breast cancers increased as the age decreased. Conclusion: The high percentage of patients with FBC among 400 cases in this study demonstrates that in order to design an infrastructural diagnostic protocol and screening of patients with FBC, a precise survey related to frequency and founder mutations of FBC is needed nationwide.

Service Information System(SIS) with Real Time Using RFID and X-Internet in Ubiquitous Environments (유비쿼터스 환경에서 RFID와 X-Internet을 이용한 실시간 서비스 정보 시스템)

  • Jo Young-Ung;Lee Eung-Joo;Kim Dong-Kyu;Kwon Ki-Ryong
    • Journal of Korea Multimedia Society
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    • v.8 no.10
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    • pp.1391-1402
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    • 2005
  • All industrial Products of today are various demand of customers and are switchovered the manufacturing system of a small quantity batch production. Its life cycle was very shortened. An enterprise is improved to satisfaction with external customers and internal customers of infinity competition time. They can exist on achieving customer satisfaction management. In this paper, a new implementation of service information system (SIS) with real time using RFID and X-Internet in Ubiquitous environments is proposed. The proposed SIS system has Web architecture based on XML and has a new X-Internet environment overcoming limitation of Client/server architecture. The service information system analyze its material data and suppress the same CLAIM creation. The implementation method of real time SIS system using RFID and X-Internet is proposed for contribution of business market reducing F-Cost.

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Development of Speech Recognition System based on User Context Information in Smart Home Environment (스마트 홈 환경에서 사용자 상황정보 기반의 음성 인식 시스템 개발)

  • Kim, Jong-Hun;Sim, Jae-Ho;Song, Chang-Woo;Lee, Jung-Hyun
    • The Journal of the Korea Contents Association
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    • v.8 no.1
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    • pp.328-338
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    • 2008
  • Most speech recognition systems that have a large capacity and high recognition rates are isolated word speech recognition systems. In order to extend the scope of recognition, it is necessary to increase the number of words that are to be searched. However, it shows a problem that exhibits a decrease in the system performance according to the increase in the number of words. This paper defines the context information that affects speech recognition in a ubiquitous environment to solve such a problem and develops user localization method using inertial sensor and RFID. Also, we develop a new speech recognition system that demonstrates better performances than the existing system by establishing a word model domain of a speech recognition system by context information. This system shows operation without decrease of recognition rate in smart home environment.

Design of Ubiquitous Payment Process for Enhancing Seamlessness and Privacy (연결완전성 제고와 프라이버시 보호를 위한 유비쿼터스 지불 프로세스의 설계)

  • Lee, Kyoung Jun;Jeong, Mu Jeong
    • Journal of Intelligence and Information Systems
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    • v.12 no.3
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    • pp.1-13
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    • 2006
  • Ubiquitous computing is a study area explained in a myriad of contexts and technological terms. Payment, however, refers in nature to an act of money transfer from one entity to another, and it is obvious that a payment method will be valued as long as the transaction can be completed with safety no matter what technology was used. The key to U-payment is convenience and security in the transfer of financial information. The purpose of this paper is to find a desirable U-payment scheme by looking at the characteristics of seamlessness under the ubiquitous environments, strong personal device, and peer-based information transactions. We also propose U-SDT Protocol integrating technologies such as Radio Frequency Identification (RFID), Bluetooth, Personal Payment Device, Account Managing Application and Transaction ID as a way to make transactions between users seamless and secure better privacy protection.

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Method on Radar deployment for Ballistic Missile Detection Probability Improvement (탄도미사일 탐지확률 향상을 위한 레이더 배치 방안)

  • Park, Tae-yong;Lim, Jae-sung
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.20 no.3
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    • pp.669-676
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    • 2016
  • North Korea has various ballistic missiles from short range to long range such as inter continental ballistic missiles. Short range ballistic missiles such as SCUD series are threatening to Korea peninsula. Therefore Korea is constructing various missile defense systems to protect country. Parameters influencing the received power from the target to the radar are transmitting power, antenna gain, carrier frequency, RCS(Radar Cross Section) of target and distance from radar to target. Especially, RCS and distance from target are not radar performance defined parameters but external parameters. Therefore radar deployment position that large RCS can be observed and target to radar distance should be considered in parallel to improve target detection probability. In this paper, RCS pattern of SCUD-B ballistic missile is calculated, received power is analyzed based on radar deployment position during ballistic missile trajectory and methode for optimum radar deployment position to improve target detection probability is suggested.

Breast Feeding and Breast Cancer Risk: A Case-control Study in Korea

  • Do, Min-Hee;Lee, Sang-Sun;Jung, Pa-Jong;M.D.;Lee, Min-Hyuk;M.B.
    • Nutritional Sciences
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    • v.3 no.2
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    • pp.77-82
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    • 2000
  • We carried out a case-control study to investigate protective effect of lactating against breast cancer in Korea. Cases (n=108) were the newly histologically identified breast cancer between December 1997 and August 1999. Hospital-based controls were selected by frequency matching method with age ($\pm$4 age) and menopausal status from the patients at the same hospital in the plastic surgery, general surgery and opthalmology department. Interviews included information on general characteristics of subjects, disease history, family history of breast cancer, vitamin supplementation, alcohol intake, food intake, and reproductive factors as well as lactation history. Odds ratio (OR) and 95% Confidence Intervals (CI) were calculated by using unconditional logistic regression. Age distribution of case control subjects were similar. Late menarche age $\geq$ 17 in premenopausal women was related to the lower risk of breast cancer OR = 0.41, 95% CI = 0.28-0.91. Family history of breast cancer was related to the higher risk of breast cancer only in premenopausal women (OR = 2.07, 95% CI = 1.35-2.71). Higher body mass index mass index (> 30) were associated with higher risk of breast cancer in postmenopausal women. For premenopausal women, women who had lactated $\geq$ 12 months to the first child had a significantly lower risk (OR = 0.53, 95% CI = 0.24-0.97) than the women had no breast feeding experience. However, results from postmenopausal women did not show an association with decreased breast cancer risk. These findings suggest that lactation may be a protective factor of breast cancer in Korean women.

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The Design of Motion Estimation Hardware for High-Performance HEVC Encoder (고성능 HEVC 부호기를 위한 움직임추정 하드웨어 설계)

  • Park, Seungyong;Jeon, Sunghun;Ryoo, Kwangki
    • Journal of the Korea Institute of Information and Communication Engineering
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    • v.21 no.3
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    • pp.594-600
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    • 2017
  • This paper proposes a global search based motion estimation algorithm for high performance HEVC encoder and its hardware architecture. To eliminate temporal redundancy, motion estimation in HEVC inter-view prediction uses global search and fast search algorithm to search for a predicted block having a high correlation with the current PU in an interpolated reference picture. The global search method predicts the motion of all candidate blocks in a given search area, thus ensuring optimal results, but has a disadvantage of large computation time. Therefore we propose a new algorithm that reduces computational complexity by reusing SAD operation in global search to reduce computation time of inter prediction. As a result of applying the proposed algorithm to standard software HM16.12, the computation time was reduced by 61%, BDBitrate by 11.81%, and BDPSNR by about 0.5% compared with the existing search algorithm. As a result of hardware design, the maximum operating frequency is 255 MHz and the total number of gates is 65.1K.