• ETRI Journal
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• v.29 no.1
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• pp.95-98
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• 2007

A low-profile phased array antenna with a low sidelobe was designed and fabricated using a genetic algorithm (GA). The subarray distances were optimized by GA with chromosomes of 78 bits, a population of 100, a crossover probability of 0.9, and a mutation probability of 0.005. The array antenna has 24 subarrays in 14 rows, and is designed as a mobile terminal for Ku-band satellite communication. The sidelobe level was suppressed by 6.5 dB after optimization, compared to the equal spacing between subarrays. The sidelobe level was verified from the far-field pattern measurement by using the fabricated array antenna with optimized distance.

• Journal of the Korean Ceramic Society
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• v.34 no.7
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• pp.731-737
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• 1997

TixZr1-xC(0$0^{\circ}C$, 5.1 mm/sec respectively. The relative density, three point flexural strength, and the hardness of composites, which was sintered at 190$0^{\circ}C$ for 60 min by using hot-pressing under a pressure of 30 MPa, were 99%, 525 MPa and 24 GPa respectively.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.5
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• pp.115-120
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• 2006

A Korean Road Roughness Classification(KRC) method is proposed. Using a dynamic road profiling device equipped with the Accelerometer Established Inertial Profiling Reference(AEIPR) method, road profile measurement is performed on various types of public paved roads in Korea. The road profiling data are processed to classify the characteristics of Korean road roughness. The resultant Korean road roughness classification(KRC) is shown different characteristics compared to the road classification proposed by ISO, MIRA, and Wong. The proposed KRC is composed of 8 classes(A-H, very good-poor) based on the power spectral density and is in good agreements with the characteristics of Korean paved road roughness and can be used well in vehicle ride comfort simulation using domestic road profile.

• 한국신재생에너지학회:학술대회논문집
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• 2006.06a
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• pp.451-454
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• 2006

Fiber optic distributed temperature sensing and thermal line sensor are applied in an observation borehole and a loom deep borehole heat exchanger. For the case of permanently installed system fiber optic DTS is very useful. By comparing with TLS, fiber optic DTS shows good accuracy and reliability. Ground water flow can give influences at heat exchange rate of the heat pump system. According to the hydraulic characteristics and temperature-depth profile, we consider that temperature-depth profile do not seem to be dependent on ground water flow. A permanent installation of fiber optic cable is expected as a reliable temperature measurement technique in a borehole heat exchanger system.

• Therapeutic Science for Rehabilitation
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• v.11 no.2
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• pp.7-24
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• 2022

Objective : To develop standardized assessment tools that evaluate the multi-aspect lifestyles of children and adolescents, we aimed to systematically analyze lifestyle assessment tools and lifestyle component-specific assessment tools. Methods : The study period was 2001-2020, with search engines using CINANL, NDSL, PubMed, and RISS. Search key words used 'lifestyle assessment' OR 'lifestyle profile' OR 'lifestyle test', 'physical activity assessment' OR 'physical activity participation profile', 'nutrition assessment' OR 'nutrition profile', 'activity participation assessment' OR 'activity participation profile'. Results : A total of 24 evaluation tools were selected after 5,883 studies reviewed the title, abstract, and full text after deduplication. The detailed results resulted in five lifestyle assessment tools, seven physical activity assessment tools, nine nutrition assessment tools, and three activity participation assessment tools. Conclusion : For the lifestyle assessment tools for children and adolescents, the component items, measurement methods, and age of assessment of each item were analyzed. It is hoped that this will be used as a basis for the development of standardized assessment tools to assess the multi-aspect lifestyles of children and adolescents in the future.

• Journal of Radiation Protection and Research
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• v.41 no.2
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• pp.173-178
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• 2016

Background: In situ gamma spectrometry has been used to measure environmental radiation, assumptions are usually made about the depth distribution of the radionuclides of interest in the soil. The main limitation of in situ gamma spectrometry lies in determining the depth distribution of radionuclides. The objective of this study is to develop a method for subsurface characterization by in situ measurement. Materials and Methods: The peak to valley method based on the ratio of counting rate between the photoelectric peak and Compton region was applied to identify the depth distribution. The peak to valley method could be applied to establish the relation between the spectrally derived coefficients (Q) with relaxation mass per unit area (${\beta}$) for various depth distribution in soil. The in situ measurement results were verified by MCNP simulation and calculated correlation equation. In order to compare the depth distributions and contamination levels in decommissioning KRR site, in situ measurement and sampling results were compared. Results and Discussion: The in situ measurement results and MCNP simulation results show a good correlation for laboratory measurement. The simulation relationship between Q and source burial for the source layers have exponential relationship for a variety depth distributions. We applied the peak to valley method to contaminated decommissioning KRR site to determine a depth distribution and initial activity without sampling. The observed results has a good correlation, relative error between in situ measurement with sampling result is around 7% for depth distribution and 4% for initial activity. Conclusion: In this study, the vertical activity distribution and initial activity of $^{137}Cs$ could be identifying directly through in situ measurement. Therefore, the peak to valley method demonstrated good potential for assessment of the residual radioactivity for site remediation in decommissioning and contaminated site.

• Journal of Physiology & Pathology in Korean Medicine
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• v.22 no.5
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• pp.1047-1056
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• 2008

If we can evaluate the training results more appropriately and analyze the psychological changes in more objectively, the training can be more efficient and it can help to solve the problems during the training. This research analyzed the similarity and differences of Yangseng Qigong and psychological skill training's components and measurement methods. Also, the research further studied psychological skill training's measurement method. Results : The measurement type of Yangseng Qigong are Sagong, a record of Sagong, Damgong, IIgi, and Sogyeol. Similarly, the measurement type of psychological skills training are questionnaire, interview, personal profile, and observation of a single subject. Despite the similarities between the measurement type of Yangsaeng Qigong and psychological skills training, unfortunately there are differences in the contents. Thus, If we introduce strengths of each method to the other, we may have better measurement methods. The questionnaire method of psychological skills training is the most commonly used method, because it gives concrete, objective, reliable and highly reproducible results. If we refer to the questionnaire development process in psychological skills training, we can have objective and concrete measurement tool for Yangsaeng Qigong training. In the psychological skills training measurement tool development process, there are 5 stages; test conception, test preparation, test execution, question analysis, and test modification. Furthermore, the requirements for the good survey are reliability, validity, practicality, and cultural appropriateness. Through this study, we reached the conclusion that we need to combine two methods together to develop a better method because Yangsaeng Qigong places importance on comprehensive method and realization while psychological skills training places importance on analytical method and objective evaluation. And It seems that a practical study is needed to resolve the concerete problems of Yansaeng Qigong through these concrete cases.

• Journal of the Korean Society for Precision Engineering
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• v.31 no.7
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• pp.605-613
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• 2014

Scanning white-light interferometry is an important measurement option for many surfaces. However, serious profile measurement errors can be present when measuring free-form surfaces being highly curved or tilted. When the object surface slope is not zero, the object and reference rays are no longer common path and optical aberrations impact the measurement. Aberrations mainly occur at the beam splitter in the interference objective and from misalignment in the optical system. Both effects distort the white-light interference signal when the surface slope is not zero. In this paper, we describe a modified version of white-light interferometry for eliminating these measurement errors and improving the accuracy of white-light interferometry. Moreover, we report systematic errors that are caused by optical aberrations when the object is not flat, and compare our proposed method with the conventional processing algorithm using the random ball test.

• Transactions of the Society of Information Storage Systems
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• v.8 no.2
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• pp.44-49
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• 2012

We measured the surface flatness of both sides for refractive media using the transmitted digital holography method. To enhance the accuracy of the result, phase-shifting system was used. With two different phase modulation of reference beam, the phase profile of object can be easily obtained. Thus, we proposed the surface measurement method which can measure large area fast, compared with conventional methods. To guarantee the reliability of obtained result, we compared with Zygo measurement system. With the proposed method, the surface flatness of $3.45{\mu}m$ resolution could be obtained.

• Journal of the Korean Society of Costume
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• v.40
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• pp.81-93
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• 1998

It is necessary to research shape of the breast of girls at adolescence for developing well-fit brassiers. 313 participants reside in Chonju and Kunsan were gathered for body measurement. The conclusion of this study can be summarized as follows. 1) The Analysis of Body Shape by Measurement. Comparing Age GroupⅠ(aged 10 to 12)' measurement with Age GroupⅡ(aged 13 to 15)', Each items has statistical significance. Two groups differed in the length, girth, depth, width items. 2) Factor Analysis of Body Measurement (1) Age GroupⅠ'characteristics were categorized Three Factor : Breast size and breast apex length. Breast volume, Length of the Breast part. (2) Age GroupⅡ' characteristics consist of four factors, which are named as breast size and its jut (first factor), breast volume (second factor), contour of breast profile & its jut (third factor), shoulder length (fourth factor). 3) Characteristics of Breast Shape. (1) Breast shapes of Age GroupⅠ are classified into three types. Types 1 is a protruded and more voluminous shape. Type 2 is the most voluminous and breast fatness is highest. Type 3 is the smallest and flat shape growing now. (2) Breast shapes of Age GroupⅡ are also classified into three types. Type 1 is the longest in length and middle in fatness, voluminous in size. Type 2 is the smallest in stature and the slimmest in fatness in breast shape. Type 3 is middle in length, the fattest and the most voluminous in breast.