• Nutrition Research and Practice
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• 제8권5호
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• pp.595-601
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• 2014

BACKGROUND/OBJECTIVES: Educational interventions targeted food selection perception, knowledge, attitude, and behavior. Education regarding irradiated food was intended to change food selection behavior specific to it. SUBJECTS AND METHODS: There were 43 elementary students (35.0%), 45 middle school students (36.6%), and 35 high school students (28.5%). The first step was research design. Educational targets were selected and informed consent was obtained in step two. An initial survey was conducted as step three. Step four was a 45 minute-long theoretical educational intervention. Step five concluded with a survey and experiment on food selection behavior. RESULTS: As a result of conducting a 45 minute-long education on the principles, actual state of usage, and pros and cons of irradiated food for elementary, middle, and high-school students in Korea, perception, knowledge, attitude, and behavior regarding the irradiated food was significantly higher after the education than before the education (P < 0.000). CONCLUSIONS: The behavior of irradiated food selection shows high correlation with all variables of perception, knowledge, and attitude, and it is necessary to provide information of each level of change in perception, knowledge, and attitude in order to derive proper behavior change, which is the ultimate goal of the education.

• Journal of Power Electronics
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• 제18권4호
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• pp.1015-1026
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• 2018

A family of dual-DC-input (DI) dual-buck inverters (DBIs) is proposed by employing a DI switching cell as the input of traditional DBIs. Three power ports, i.e. a low voltage DC input port, a high voltage DC input port and an AC output port, are provided by the proposed DI-DBIs. A low voltage DC source, whose voltage is lower than the peak amplitude of the AC side voltage, can be directly connected to the DI-DBI. This supplies power to the AC side in single-stage power conversion. When compared with traditional DBI-based two-stage DC/AC power systems, the conversion stages are reduced, and the power rating and power losses of the front-end Boost converter of the DI-DBI are reduced. In addition, five voltage-levels are generated with the help of the two DC input ports, which is a benefit in terms of reducing the voltage stresses and switching losses of switches. The topology derivation method, operation principles, modulation strategy and characteristics of the proposed inverter are analyzed in-depth. Experimental results are provided to verify the effectiveness and feasibility of the proposed DI-DBIs.

• Environmental Analysis Health and Toxicology
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• 제29권
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• pp.16.1-16.9
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• 2014

Objectives Rapid increase in engineered nanoparticles (ENPs) in many goods has raised significant concern about their environmental safety. Proper methodologies are therefore needed to conduct toxicity and exposure assessment of nanoparticles in the environment. This study reviews several analytical techniques for nanoparticles and summarizes their principles, advantages and disadvantages, reviews the state of the art, and offers the perspectives of nanometrology in relation to ENP studies. Methods Nanometrology is divided into five techniques with regard to the instrumental principle: microscopy, light scattering, spectroscopy, separation, and single particle inductively coupled plasma-mass spectrometry. Results Each analytical method has its own drawbacks, such as detection limit, ability to quantify or qualify ENPs, and matrix effects. More than two different analytical methods should be used to better characterize ENPs. Conclusions In characterizing ENPs, the researchers should understand the nanometrology and its demerits, as well as its merits, to properly interpret their experimental results. Challenges lie in the nanometrology and pretreatment of ENPs from various matrices; in the extraction without dissolution or aggregation, and concentration of ENPs to satisfy the instrumental detection limit.

• 한국실내디자인학회논문집
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• 제19권5호
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• pp.38-47
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• 2010

The purpose of this study is to examine the characteristics by design component elements of the facade in elementary school buildings after the 7th educational curriculum. This study choose twenty five elementary school as the subjects of the study. And among many elevations of building, an elevation that is alongside of the schoolyard is chosen because this elevation has the highest visual influence on passers-by. To begin with, this elevation is divided into the roof and the surface of a wall, The roof is divided into roof styles, existence of roof and materials. The surface of a wall is divided into design principles(balance, contrast, rhythm), the formal organization(basic elements and form, and transformation of form), the ornamental composition, materials and colors. The results of the research are summarized as follows: First of all, motifs of classical architecture were well expressed in this period and postmodern tendency had been shown until 2005. After Build Transfer Lease(BTL), however, tendency of classical architecture, contrast by the size of the form and base element by point disappeared. Instead, asymmetrical and flat tendency is expressed. Also, emphasized design of the building elevation appear by basic colors of Munsell, not motifs of classical architecture.

• 대한한의학원전학회지
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• 제13권2호
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• pp.14-20
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• 2000

Both of the three Um and three Yang and the six hyo(六爻) of Iching are based on Um and Yang theory and five phases theory. This paper is about mutual relation of them. First, every change in the universe is induced by Un and Ki. Un is the nature that things have their own. Ki is surroundings that things change in. Second, Un and Ki are not separate things. That is they are generated by each other. Third, both of them are the signs of change which means they are similar. The first Hyo (初爻) and Kwolum-pungmok(厥陰風木), the seond Hyo(二爻) and Soum-gunhwa(少陰君火), the third Hyo(三爻) and Teum-supto(太陰濕土), the forth Hyo(四爻) and Soyang-sanghwa(少陽相火), the fifth Hyo(五爻) and Yangmyung-zogum(陽明燥金), and the sixth Hyo(六爻) and Teyang-hansu(太陽寒水) have similar principles. It is important to make clear up their meanings and mutual relation.

• 대한약침학회지
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• 제17권3호
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• pp.57-61
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• 2014

Objectives: When a person speaks, voice problems usually include pain or discomfort and/or difficulties in terms of the pitch, the loudness and the quality of the voice. When patients with voice problems induced by stroke, Parkinson's disease, and systemic diseases involving the voice are examined, generally, of the Four Diagnoses (四診), a Diagnosis of Hearing can be used in current Korean medicine. The effects of acupuncture and herb medicine on voice problems have been reported for over 20 years. However, when it comes to improvements, objective and subjective evaluation methods need to be explained. Methods: Subjective methods for evaluating voice were studied through a literature search of old medicinal books containing Korean medicine diagnostics, and an objective evaluation method using Praat software is presented. Results: Korean medicine doctors analyze the patient's voice in clinical settings unconsciously on a daily basis. However, most voice diagnoses depend on the doctor's subjective evaluation. Voice qualities can be evaluated by using the Eight Principles (八綱), including Yin-Yang; the Five Elements (Phases); the Grade, Roughness, Breathy, Asthenic, Strained (GRBAS) score, and the Visual Analogue Scale (VAS) as subjective methods, and an acoustic analysis using the Praat program can be used as an objective method. Conclusion: A more complete voice examination can be achieved by using subjective and objective methods at the same time. For an objective explanation and management of patient's voice problems or systemic disorders, an objective method should be used in Korean medicine, which already has many subjective diagnostic methods. More research needs to be conducted, and more clinical evidence needs to be collected in the future.

• 한국도서관정보학회지
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• 제33권2호
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• pp.277-302
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• 2002

본 연구는 효율적인 메타데이터간의 상호운용 방안마련을 위하여 주요 원칙들을 선정하고 이 원칙들을 기준으로 디지털자원 관리를 위한 메타데이터간의 상호운용성에 대한 실질적인 비교테이블을 제안하였다. NISO의 백서(White Paper)에서 제안한 상호연동(crosswalking)의 주요 항목들을 바탕으로 원칙들을 선정하고 이 원칙들을 기준으로 INDES 메타데이터 구조(framework)를 바탕으로 개발된 ONIX와 기존의 MARC과 Dublin Core와 비교하였다. 이들 메타데이터 요소들의 실질적인 비교를 통하여 상이한 메타데이터간의 상호운용성을 위한 어의, 구문 및 구조에 대한 공통적인 규칙을 지원하는 구문을 개발하고, 실제로 메타데이터간의 변환 시스템을 구현하는 도서관 관련 시스템 개발자들에게 있어서 필수적인 기반 연구가 되고자 하였다.

• Smart Structures and Systems
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• 제15권6호
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• pp.1439-1461
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• 2015

Design criteria, modeling rules, and analysis principles of seismic isolation systems have already found place in important building codes and standards such as the Uniform Building Code and ASCE/SEI 7-05. Although real behaviors of isolation systems composed of high damping or lead rubber bearings are nonlinear, equivalent linear models can be obtained using effective stiffness and damping which makes use of linear seismic analysis methods for seismic-isolated buildings possible. However, equivalent linear modeling and analysis may lead to errors in seismic response terms of multi-story buildings and thus need to be assessed comprehensively. This study investigates the accuracy of equivalent linear modeling via numerical experiments conducted on generic five-story three dimensional seismic-isolated buildings. A wide range of nonlinear isolation systems with different characteristics and their equivalent linear counterparts are subjected to historical earthquakes and isolation system displacements, top floor accelerations, story drifts, base shears, and torsional base moments are compared. Relations between the accuracy of the estimates of peak structural responses from equivalent linear models and typical characteristics of nonlinear isolation systems including effective period, rigid-body mode period, effective viscous damping ratio, and post-yield to pre-yield stiffness ratio are established. Influence of biaxial interaction and plan eccentricity are also examined.

• Journal of Power Electronics
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• 제17권1호
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• pp.262-271
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• 2017

This paper studies the performances of five typical Phase-locked Loops (PLLs) for distorted and unbalanced grid, which are the Decoupled Double Synchronous Reference Frame PLL (DDSRF-PLL), Double Second-Order Generalized Integrator PLL (DSOGI-PLL), Double Second-Order Generalized Integrator Frequency-Lock Loop (DSOGI-FLL), Double Inverse Park Transformation PLL (DIPT-PLL) and Complex Coefficient Filter based PLL (CCF-PLL). Firstly, the principles of each method are meticulously analyzed and their unified small-signal models are proposed to reveal their interior relations and design control parameters. Then the performances are compared by simulations and experiments to investigate their dynamic and steady-state performances under the conditions of a grid voltage with a negative sequence component, a voltage drop and a frequency step. Finally, the merits and drawbacks of each PLL are given. The compared results provide a guide for the application of current control, low voltage ride through (LVRT), and unintentional islanding detection.

• 대한한의학회지
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• 제35권2호
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• pp.28-33
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• 2014

Background: Samul-tang (Si-Wu-Tang, SMT) is a traditional herbal formula, which has been widely used to treat various diseases such as menstrual irregularity, bleeding and leucorrhea. Although many studies have investigated the pharmacological properties of SMT, its toxicity information has not yet been fully elucidated. Methods: Five Sprague Dawley (SD) rats of each sex were given a single dose (5000 mg/kg) of SMT by gavage; control rats received the vehicle only. After the single administration, mortality, clinical signs, body weight changes and gross findings were monitored for 15 days in accordance with Good Laboratory Practice (GLP) principles. Results: In a single oral dose toxicity study, there was no adverse effect on mortality, clinical sign, body weight change or gross finding in any treatment group. Conclusions: The results indicate that SMT did not induce toxic effects at a dose level up to 5000 mg/kg in rats and its median lethal dose ($LD_{50}$) was considered to be over 5000 mg/kg/day body weight for both genders.