• Title/Summary/Keyword: two dimensions

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A LATERAL CEPHALOMETRIC STUDY OF CRANIOFACIAL VARIATION IN KOREAN CHILD TWINS (한국인 쌍생아의 두개안면에 관한 X선학적 연구)

  • Lee Sang Rei
    • Journal of Korean Academy of Oral and Maxillofacial Radiology
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    • v.4 no.1
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    • pp.21-30
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    • 1974
  • A study was performed to investigate the degree of similarities and differences in components of craniofacial complex between Korean twins and normal children by lateral cephalometric analysis. Dimensions of S-N, S-Ba, N-Ba, Go-Me, Ar-Go and Ar-Me were against linear measurement and angles of N-S-Ba and gonial against measurement in twins and control groups. The lateral cephalograms of twin were composed of 88 twins aged from 7 to 12:44 males aged 10.65 and 44 females aged 9.55, while those of 50 normalities were composed of 25 males and 25 females aged 10.9 respectively. In order to analyze growth proportion and sexual differences, twins were divided into 3 groups according to two year age intervals and the author compared male with female in 3 groups. For the purpose of observing similarities and differences in twins and normalities by sex, total twins were compared with normalities. The obtained results were as follows: 1. There was no difference in craniofacial complex between plotted angular normalities. 2. In general, the measurements of male were larger than both twins and normalities, but there were no statistical sexual differences in both groups. 3. The growth proportion of mandible by aging was larger than that of face twins and those of female significances of in twins. 4. The growth pattern of gonial angle showed slightly reducing tendency in twins by aging. 5. There was little difference in the growth proportion of both male and female.

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An Experimental Study on Steering Performance of Tracked Vehicle on Deep-sea Cohesive Soft Soil by DOE using Orthogonal Arrays (직교배열표 실험계획법에 의한 심해저 점착성 연약지반용 무한궤도차량의 선회성능에 대한 실험 연구)

  • Choi, Jong-Su;Hong, Sup;Kim, Hyung-Woo
    • Journal of Ocean Engineering and Technology
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    • v.20 no.4 s.71
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    • pp.37-42
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    • 2006
  • This paper is concerned with experimental investigation of steering performance of a tracked vehicle on extremely soft soil. A tracked vehicle model with principal dimensions of 0.9 m(L)x0.75 m(B)x0.4 m(H) and weight of 167 kg was constructed with a pair of driving chain links, driven by two AC-servo motors. The tracks were configured with detachable grousers with variable span. A deep seabed was simulated by means of a bentonite-water mixture in a soil bin of 6.0 m(L)x3.7 m(B)x0.7 m(H). The turning radii of vehicle and driving torques of motors were measured with respect to experiment variables: steering ratio, driving speed, grouser chevron angle, grouser span, and grouser height. L8 orthogonal table is adopted for DOE (Design of experiment). The effects of experiment variables on steering performance are evaluated.

Fatigue Design of Mooring Lines of Floating Type Combined Renewable Energy Platforms

  • Choung, Joon-Mo;Jeon, Sang-Ik;Lee, Min-Seong
    • International Journal of Ocean System Engineering
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    • v.1 no.3
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    • pp.171-179
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    • 2011
  • This paper presents the concept design procedure of a floating-type combined renewable energy platform based on hydrodynamic analyses and is focused on the fatigue design of taut-type mooring lines of the platform. Two types of combined renewable energy platforms are considered: a combination of wind turbine, wave turbine and photovoltaic energy plant and a combination of wind turbine, current turbine and photovoltaic energy plant. The basic configurations are conceptually determined from the understanding of floating offshore plants, while the main dimensions have been determined based on a hydrostatic calculation. Fully coupled hydrodynamic analyses have been carried out to identify the motion characteristics of the floating body and the tension histories of the mooring lines. The tension history is used for the fatigue life prediction based on the rain-flow cycle counting method. For the fatigue life prediction, tension life curves from API and the Palmgren-Miner rule are employed.

Factors Associated with Health-Related Quality of Life in Tuberculosis Patients Referred to the National Research Institute of Tuberculosis and Lung Disease in Tehran

  • Kakhki, Ali Darvishpoor;Masjedi, Mohammad Reza
    • Tuberculosis and Respiratory Diseases
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    • v.78 no.4
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    • pp.309-314
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    • 2015
  • Background: In tuberculosis (TB) patients, health-related quality of life (HRQoL) is significant in self-management, which in turn can be effective in therapeutic acceptance and prevention of treatment failure due to multi-drug resistant TB. This study was conducted to evaluate HRQoL and associated factors in TB patients referred to the National Research Institute of Tuberculosis and Lung Disease (NRITLD). Methods: In this study, patients were selected from TB clinics of the NRITLD in Tehran. In addition to an Iranian version of the Short-Form Health Survey (SF-36), demographic and disease characteristic questionnaires were used for data collection. The data were then analyzed using SPSS software. Results: Two hundred five TB patients, with the average age of $42.33{\pm}17.64$ years, participated in this study. The HRQoL scores in different domains ranged from $14.68{\pm}11.60$ for role limitations due to emotional problems to $46.99{\pm}13.25$ for general health perceptions. The variables of sex, marital status, education, job status, place of residence, and cigarette smoking, influenced the HRQoL scores in different dimensions. Conclusion: According to the study findings are the important variables that influenced the HRQoL of TB patients. The consideration of its can improve the HRQoL of TB patients.

A Performance Improvement Method of PMSM Torque Control Considering DC-link Voltage Variation (DC-link 전압변동을 고려한 PMSM 토크제어의 성능 향상 방법)

  • Lee, Jung-Hyo;Won, Chung-Yuen
    • Journal of the Korean Institute of Illuminating and Electrical Installation Engineers
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    • v.28 no.11
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    • pp.112-122
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    • 2014
  • This paper proposes a PMSM torque control method considering DC-link voltage variation and friction torque. In general EV/HEV application, two dimensions look-up table(2D-LUT) is used for reference current generation due to its stable and robust torque control performance. Conventionally, this 2D-LUT is established by flux-torque table to overcome the DC-link voltage variation. However, the flux table establishment is more complex than the speed table establishment. Moreover, one flux data reflects several speed conditions in variable DC-link voltage, friction torque cannot be considered by using the flux table. In this paper, speed-torque 2D-LUT is used for current reference generation. With this table, PMSM torque control is well achieved regardless of DC-link voltage variation by the proposed control method. Simulation and experimental results validate improvement of torque control error through friction torque compensation.

An Empirical Study on the Perception of Port Service Quality - Primarily on SERVQUAL Model In Container Terminal - (항만 서비스품질 지각에 관한 연구 - 컨테이너항만의 SERVQUAL 적용을 중심으로 -)

  • 신한원;김성국;최영로
    • Journal of Korean Port Research
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    • v.15 no.1
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    • pp.1-18
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    • 2001
  • The purpose of this study is to explore the nature of the relationship between several factors representing perceived port service quality and the adaptability to the marketing strategy of container terminal. An empirical study was carried out to examine not only the determinants of port service quality using PZB's SERVQUAL model but also its implications to the service marketing strategy. The data investigating the determinants of port service quality were collected from 136 managers from shipping companies by the use of questionnaire method. Factor analysis and t-test were carried out to analyze the data. The results of this study were as follows ; First, Shipping companies perceive the port service quality on two the dimensions of personnel and material aspects. Second, Shipping companies put more emphasis on the reliance of port service quality even though the port authority offers good facilities and materials as parts of port shipping quality. Third, There is a significant relationship between the purchase intention and the customer satisfaction. These findings help not only to formulate service marketing strategy based on service quality but also to be a concept tool to enhance port service quality.

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Minimum Distance based Precoder Design for General MIMO Systems using Gram Matrix

  • Chen, Zhiyong;Xu, Xiaodong
    • Journal of Communications and Networks
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    • v.17 no.6
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    • pp.634-646
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    • 2015
  • Assuming perfect channel state information (CSI) at the transmitter and receiver, the optimization problem of maximizing the minimum Euclidean distance between two received signals by a linear precoder is considered for multiple-input multiple-output (MIMO) systems with arbitrary dimensions and arbitraryary quadrature amplitude modulation (QAM) input. A general precoding framework is first presented based on the Gram matrix, which is shown for 2-dimensional (2-D) and 3-dimensional (3-D) MIMO systems when employing the ellipse expanding method (EEM). An extended precoder for high-dimensional MIMO system is proposed following the precoding framework, where the Gram matrix for high-dimensional precoding matrix can be generated through those chosen from 2-D and 3-D results in association with a permutation matrix. A complexity-reduced maximum likelihood detector is also obtained according to the special structure of the proposed precoder. The analytical and numerical results indicate that the proposed precoder outperforms the other precoding schemes in terms of both minimum distance and bit error rate (BER).

Vibration and sound of Silla Great Bell (신라대종의 진동과 음향)

  • Kim, Seockhyun;Lee, Joong Hyeok;Byeon, Jun Ho
    • The Journal of the Acoustical Society of Korea
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    • v.36 no.3
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    • pp.186-193
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    • 2017
  • Silla Great Bell was manufactured in order to ring for the new millennium in succession to King Seongdeok Divine Bell. This study investigates how Silla Great Bell is similar to King Seongdeok Divine Bell in respect of structure and sound. First, design and manufacturing processes are introduced and dimensions of the two bells are compared and the similarity is estimated. Three main characteristics of the sound of a Korean bell are magnificent and harmonic striking sound, dynamic beat, and long lasting hum tone. These three features are compared and objectively estimated using physical parameters. The purpose of the study is to provide useful information to manufacture Korean bell which has beautiful appearance and excellent sound.

Interacting with Touchless Gestures: Taxonomy and Requirements

  • Kim, Huhn
    • Journal of the Ergonomics Society of Korea
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    • v.31 no.4
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    • pp.475-481
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    • 2012
  • Objective: The aim of this study is to make the taxonomy for classifying diverse touchless gestures and establish the design requirements that should be considered in determining suitable gestures during gesture-based interaction design. Background: Recently, the applicability of touchless gestures is more and more increasing as relevant technologies are being advanced. However, before touchless gestures are widely applied to various devices or systems, the understanding on human gestures' natures and their standardization should be prerequisite. Method: In this study, diverse gesture types in various literatures were collected and, based on those, a new taxonomy for classifying touchless gestures was proposed. And many gesture-based interaction design cases and studies were analyzed. Results: The proposed taxonomy consisted of two dimensions: shape (deictic, manipulative, semantic, or descriptive) and motion(static or dynamic). The case analysis based on the taxonomy showed that manipulative and dynamic gestures were widely applied. Conclusion: Four core requirements for valuable touchless gestures were intuitiveness, learnability, convenience and discriminability. Application: The gesture taxonomy can be applied to produce alternatives of applicable touchless gestures, and four design requirements can be used as the criteria for evaluating the alternatives.

Regional Differences of Clothing Consumption Behavior in Korean Adolescents (청소년의 의복소비행동의 지역별 비교연구)

  • 이명희;유경숙
    • Journal of the Korean Society of Costume
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    • v.54 no.5
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    • pp.13-25
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    • 2004
  • The purpose of this study was to understand regional differences of clothing consumption behavior of Korean adolescents. Subjects were 624 male and female high school students in north and south to the Hangang river, Seoul, and those in Kunsan City, Jeonlabuk-Do. The clothing consumption orientation were classified 4 dimensions by factor analysis: brand orientation, others-sensitivity, impulse buying, and advertizement influence. Female students were significantly higher in brand orientation, others-sensitivity, and impulse buying than males. Students in the south Seoul are influenced more than the other two regions by brand orientation, others-sensitivity, and impulse buying. There were significant interaction effects in brand orientation and others sensitivity by sender and region. In the north Seoul students, males demonstrated less brand orientation than females. while south Seoul male students did high others-sensitivity tendency than male of the other regions. Males of north Seoul and Kunsan spent less expense for clothing, but south Seoul students equally in males and females spent the highest for clothing. About one-third of all adolescents had imitated appearance of an entertainer. mostly for hair-styles of them. Major commodities that teenagers purchased on impulse were shirts, pants, shoes, and bags. Since shoes prevailed among purchased famous brands, teenagers seem to be most interested in shoes as far as the brand was concerned in particular. In general, clear differences of gender and region were observed in clothing consumption behavior: male adolescents in the north Seoul and Kunsan City exhibited Passive clothing behavior, whereas south Seoul males and females showed active behavior and gender-equality.