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A Research on Ball-Balancing Robot (볼 벨런싱 로봇에 관한 연구)

  • Kim, Ji-Tae;Kim, Dae-young;Lee, Won-Joon;Jin, Tae-Seok
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2017.05a
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    • pp.463-466
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    • 2017
  • The purpose of this paper is to develop a module capable of all-directional driving different from conventional wheeled robots, and to solve the problems of the conventional mobile robot with side driving performance degradation, It is possible to overcome the disadvantages such as an increase in the time required for the unnecessary driving. The all - direction spherical wheel drive module for driving a ball - balancing robot is required to develop a power transfer mechanism and a driving algorithm for driving the robot in all directions using three rotor casters. 3DoF (Axis) A driver with built-in forward motion algorithm is embedded in the module and a driving motor module with 3DoF (axis) for driving direction and speed is installed. The movement mechanism depends on the sum of the rotation vectors of the respective driving wheels. It is possible to create various movement directions depending on the rotation and the vector sum of two or three drive wheels. It is possible to move in different directions according to the rotation vector field of each driving wheel. When a more innovative all-round spherical wheel drive module for forward movement is developed, it can be used in the driving part of the mobile robot to improve the performance of the robot more technically, and through the forward-direction robot platform with the drive module Conventional wheeled robots can overcome the disadvantage that the continuous straightening performance is lowered due to resistance to various environments. Therefore, it is necessary to use a full-direction driving function as well as a cleaning robot and a mobile robot applicable in the Americas and Europe It will be an essential technology for guide robots, boarding robots, mobile means, etc., and will contribute to the expansion of the intelligent service robot market and future automobile market.

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A Study of Hydrodynamics and Reaction Characteristics in Relation to the Desulfurization Temperatures of Zn-Based Solid Sorbent in the Lab-scale High Pressure and High Temperature Desulfurization Process (실험실규모 고온고압건식탈황공정의 수력학적 특성 및 탈황온도에 따른 아연계 탈황제의 반응특성 연구)

  • Kyung, Dae-Hyun;Kim, Jae-Young;Jo, Sung-Ho;Park, Young Cheol;Moon, Jong-Ho;Yi, Chang-Keun;Baek, Jeom-In
    • Korean Chemical Engineering Research
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    • v.50 no.3
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    • pp.492-498
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    • 2012
  • In this study, hydrodynamics such as solid circulation rate and voidage in the desulfurizer and the reaction characteristics of Zn-based solid sorbents were investigated using lab-scale high pressure and high temperature desulfurization process. The continuous HGD (Hot Gas Desulfurization) process consist of a fast fluidized bed type desulfurizer (6.2 m tall pipe of 0.015 m i.d), a bubbling fluidized bed type regenerator (1.6 m tall bed of 0.053 m i.d), a loop-seal and the pressure control valves. The solid circulation rate was measured by varying the slide-gate opening positions, the gas velocities and temperatures of the desulfurizer and the voidage in the desulfurizer was derived by the same way. At the same gas velocities and the same opening positions of the slide gate, the solid circulation rate, which was similar at the temperature of $300^{\circ}C$ and $550^{\circ}C$, was low at those temperatures compared with a room temperature. The voidage in the desulfurizer showed a fast fluidized bed type when the opening positions of the slide gate were 10~20% while that showed a turbulent fluidized bed type when those of slide gate were 30~40%. The reaction characteristics of Zn-based solid sorbent were investigated by different desulfurization temperatures at 20 atm in the continuous operation. The $H_2S$ removal efficiency tended to decrease below the desulfurization temperature of $450^{\circ}C$. Thus, the 10 hour continuous operation has been performed at the desulfurization temperature of $500^{\circ}C$ in order to maintain the high $H_2S$ removal efficiency. During 10 hour continuous operation, the $H_2S$ removal efficiency was above 99.99% because the $H_2S$ concentration after desulfurization was not detected at the inlet $H_2S$ concentration of 5,000 ppmv condition using UV analyzers (Radas2) and the detector tube (GASTEC) which lower detection limit is 1 ppmv.

Quality Characteristics of Sourdough Breads Added with Red Koji Rice Sourdough Powder (분말화한 홍국 Sourdough를 첨가한 Sourdough Bread의 품질 특성)

  • Lee, Jae-Hoon;Kwak, Eun-Jung;Lee, Young-Soon
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.37 no.3
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    • pp.333-341
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    • 2008
  • The objective of this study was to investigate the physical characteristics of sourdough starter containing red koji rice (SD1: 0%, SD2: 10%, SD3: 20% and SD4: 40%) and to compare the quality characteristics of sourdough breads containing 10% red koji rice powder with those of sourdough bread containing with vollsauer powder (VPB) and white wheat bread (WWB) prepared with starter SD1. The activity of ${\beta}$-amylase increased with increasing amount of red koji rice. Organic acids of sourdough starter with red koji rice (SD2, SD3 and SD4) were higher than that of sourdough starter SD1. The peak time, peak value width of tail, pH, and L value were high in WWB, while the proofing power and a and b values of WWB were lower than those of VPB and sourdough bread containing SD1 (SPB1), SD2 (SPB2), SD3 (SPB3), or SD4 (SPB4). The lowest pH, baking loss, and specific volume were observed with the VPB. The baking loss of SPB4 (sourdough bread containing SD4) was the highest (13.01%). Overall, hardness and springiness were low in sourdough bread containing red koji rice powder, whereas sourness and off-flavor were higher than in VPB. Results of specific volumes, hardness and sensory evaluation indicated that the addition of 10% red koji rice powder to sourdough starter can improve the quality characteristics of the sourdough bread.

Plasma-assisted Catalysis for the Abatement of Isopropyl Alcohol over Metal Oxides (금속산화물 촉매상에서 플라즈마를 이용한 IPA 저감)

  • Jo, Jin Oh;Lee, Sang Baek;Jang, Dong Lyong;Park, Jong-Ho;Mok, Young Sun
    • Clean Technology
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    • v.20 no.4
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    • pp.375-382
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    • 2014
  • This work investigated the plasma-catalytic decomposition of isopropyl alcohol (IPA) and the behavior of the byproduct compounds over monolith-supported metal oxide catalysts. Iron oxide ($Fe_2O_3$) or copper oxide (CuO) was loaded on a monolithic porous ${\alpha}-Al_2O_3$ support, which was placed inside the coaxial electrodes of plasma reactor. The IPA decomposition efficiency itself hardly depended on the presence and type of metal oxides because the rate of plasma-induced decomposition was so fast, but the behavior of byproduct formation was largely affected by them. The concentrations of the unwanted byproducts, including acetone, formaldehyde, acetaldehyde, methane, carbon monoxide, etc., were in order of $Fe_2O_3/{\alpha}-Al_2O_3$ < $CuO/{\alpha}-Al_2O_3$ < ${\alpha}-Al_2O_3$ from low to high. Under the condition (flow rate: $1L\;min^{-1}$; IPA concentration: 5,000 ppm; $O_2$ content: 10%; discharge power: 47 W), the selectivity towards $CO_2$ was about 40, 80 and 95% for ${\alpha}-Al_2O_3$, $CuO/{\alpha}-Al_2O_3$ and $Fe_2O_3/{\alpha}-Al_2O_3$, respectively, indicating that $Fe_2O_3/{\alpha}-Al_2O_3$ is the most effective for plasma-catalytic oxidation of IPA. Unlike plasma-alone processes in which tar-like products formed from volatile organic compounds are deposited, the present plasma-catalyst hybrid system did not exhibit such a phenomenon, thus retaining the original catalytic activity.

Verifying the Classification Accuracy for Korea's Standardized Classification System of Research F&E by using LDA(Linear Discriminant Analysis) (선형판별분석(LDA)기법을 적용한 국가연구시설장비 표준분류체계의 분류 정확도 검증)

  • Joung, Seokin;Sawng, Yeongwha;Jeong, Euhduck
    • Management & Information Systems Review
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    • v.39 no.1
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    • pp.35-57
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    • 2020
  • Recently, research F&E(Facilities and Equipment) have become very important as tools and means to lead the development of science and technology. The government has been continuously expanding investment budgets for R&D and research F&E, and the need for efficient operation and systematic management of research F&E built up nationwide has increased. In December 2010, The government developed and completed a standardized classification system for national research F&E. However, accuracy and trust of information classification are suspected because information is collected by a method in which a user(researcher) directly selects and registers a classification code in NTIS. Therefore, in the study, we analyzed linearly using linear discriminant analysis(LDA) and analysis of variance(ANOVA), to measure the classification accuracy for the standardized classification system(8 major-classes, 54 sub-classes, 410 small-classes) of the national research facilities and equipment established in 2010, and revised in 2015. For the analysis, we collected and used the information data(50,271 cases) cumulatively registered in NTIS(National Science and Technology Service) for the past 10 years. This is the first case of scientifically verifying the standardized classification system of the national research facilities and equipment, which is based on information of similar classification systems and a few expert reviews in the in-outside of the country. As a result of this study, the discriminant accuracy of major-classes organized hierarchically by sub-classes and small-classes was 92.2 %, which was very high. However, in post hoc verification through analysis of variance, the discrimination power of two classes out of eight major-classes was rather low. It is expected that the standardized classification system of the national research facilities and equipment will be improved through this study.

Oral Health Care Knowledge and Education of Out-patients in the Military Hospital (구강보건관리 지식 및 교육정도에 기반한 군병원 외래환자의 구강건강상태)

  • Byun, Jin Young;Lee, Myeng Hee;Moon, Cheol Hyun;Im, Jeong Soo;Gang, Cheon-Guk;Seo, Hwa Jeong
    • Journal of dental hygiene science
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    • v.10 no.6
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    • pp.481-487
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    • 2010
  • This study was conducted with 200 outpatients and inpatients of military hospitals around the northern region of Gyeonggi-Do. 182 questionnaires in 200 copies were returned, which meant that the return rate was 91%. 180 questionnaires were used for analysis because 2 questionnaires included untrustful responses. The questionnaires were filled by the subjects for 20 days from Dec. 1, 2008 to Dec. 20, 2008. First, in accordance with the examination on the awareness and knowledge on the dental caries, periodontal disease and oral health care, the awareness on the prevention of dental caries was 18.733 points in 25 full points. Second, for the examination on the oral health status according to the interest and education related to oral health care, the interest and oral health status showed the statistically significant relationship(P=0.0083). Third, in accordance with the analysis on the relationship between oral health status and awareness and knowledge on oral health care, for the awareness on the prevention of dental caries, the answer "Not healthy" was 19.188 points, the answer "Average" 18.210 points and the answer "Healthy" 18.971 points. In conclusion, the higher the interest on the education and oral health care was, the better the behavior for oral health care and oral health status were. As a result, the oral health care is essential for each individual to keep good health status. For keeping and deploying the best fighting power in the military and the country, the oral health program shall be pushed ahead as the key project to keep the good oral status of soldiers.

Quality Characteristics of Sikhye added with Mulberry (Morus alba L.) Fruit Concentrate (오디농축액 첨가에 따른 식혜의 품질 특성)

  • Yang, Ji-won;Jung, Sung Keun;Song, Kyung-Mo;Kim, Young Ho;Lee, Nam Hyouck;Hong, Sang Pil;Lee, Kyung Hee;Kim, Young Eon
    • Journal of the East Asian Society of Dietary Life
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    • v.26 no.1
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    • pp.44-54
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    • 2016
  • This study compared the physicochemical characteristics, proximate composition, taste compounds, and antioxidant properties of Sikhye prepared with mulberry fruit concentrate. Analysis of the physicochemical characteristics of Sikhye added with mulberry indicated that sugar content and titratable acidity increased significantly with increasing mulberry concentration, whereas pH decreased significantly. The whiteness index (L) was 36.77~51.40, which significantly decreased with increasing mulberry concentrate. The redness index (a) was -0.90~1.97 and highest in Sikhye sample containing 4% mulberry concentrate. The yellow index (b) was 0.03~1.90 and highest in Sikhye sample containing 1% mulberry concentrate. Analysis of the antioxidant properties of Sikhye added with mulberry indicated that total polyphenol content and flavonoid content increased significantly as the amount of mulberry concentrate increased above 1%. Total anthocyanin color also increased significantly with increasing mulberry concentrate. The mulberry Sikhye sample containing 8% extract showed the strongest antioxidant properties based on DPPH radical scavenging activity, reducing power, and FRAP assay. Evaluation of the sensory properties of Sikhye added with mulberry revealed that the most preferred flavor, color, and taste were observed in Sikhye samples containing 2%, 4%, and 8% extract, respectively. However, the highest overall preference was observed in Sikhye sample containing 2% extract, indicating that 2% concentration was most suitable for Sikhye and that flavor and aftertaste were more critical than taste. Analysis of the storage characteristics of Sikhye added with mulberry indicated that total bacteria count increased across all samples with increased storage period. However, total bacteria count in the added mulberry concentration group decreased in comparison to the control group as the amount of added mulberry increased.

Wave Simulation for Submarine Cable Route of Southwest Sea Offshore Wind Farm Using the SWAN Model (SWAN 모델을 이용한 서남해 해상풍력단지 해저케이블 경과지의 파랑 수치모의)

  • Ryu, Hwang-Jin;Kim, Sang-Ho;Kwoun, Chul-Hui;Cho, Kwang-Woo;Maeng, Jun-Ho
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.21 no.5
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    • pp.583-590
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    • 2015
  • Submarine cable installation is essentials for grid connection between existing power grid and newly produced electricity which will be from offshore wind farm in Southwest sea area of Korea. Especially, submarine cable route and protection method is designed in order to ensure the economical efficiency, workability and stability of submarine cable installation. On this paper, we will give the basic information about the submarine cable route and protection method of offshore wind farm which will be built in Southwest sea area of Korea. For this, we have a numerical simulation at high and low tide based on the third-generation wave model SWAN(Simulating WAves Nearshore) using the long term wave data from Korea Institute of Ocean Science and Technology(KIOST). The results of the study, year mean Hs is 1.03m, Tz is 4.47s and dominant wave direction is NW and SSW When the incident wave direction is NW(Hs: 7.0 m, Tp: 11.76s), the distribution of shallow water design wave height Hs was calculated about 4.0~5.0m at high tide and 2.0~3.0m at low tide. When the incident wave direction is SSW(Hs: 5.84 m, Tp: 11.15s), the distribution of shallow water design wave height Hs was calculated about 3.5~4.5m at high tide and 1.5~2.5m at low tide. The wave direction on a dominant influence in the section of longitude UTM 249749~251349(about 1.6 km) and UTM 251549~267749(about 16.2 km) in the submarine cable route are each NW and SSW. Prominently, wave focusing phenomenon appears between Wi-do and Hawangdeung-do, in this sea area is showing a relatively high wave hight than the surrounding sea areas.

A Review of Responses of Nursing Students Following Clinical Maternity Nursing Practice (모성 간호 실습 후 분만과정에 대한 간호학생의 심리적 반응 고찰 -모성 간호 실습, 실습에 대한 간호학생의 심리적 반응-)

  • Cho, Cheong-Ho
    • 모자간호학회지
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    • v.4 no.1
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    • pp.41-51
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    • 1994
  • The purposes of this study were to identify responses of nursing students following clinical maternity nursing practice, to develop data of further effective clinical maternity nursing practice, to understand nursing students perceive the natural maturation process toward pregnancy delivery and puerperal process, to help the nursing students achieve personality growth and development through clinical maternity nursing practice. The subjects were 35 senior nursing students from the Department of Nursing Science of Chung-Ang University. The data were collected from the 1st semester (Feb.22$\sim$June 9) to the 2nd semester(Aug.23$\sim$Nov.10), 1993 through self-reporting using an open ended questionnaire about perception and feelings regarding the normal delivery process. The data analysis used descriptive method. Results of the study were as follows : 1. Following clinical practice in maternity nursing, the responses of the nursing students were collected included both positive and negative aspects. The positive responses were classified in to four categories and each category included subgroups. One group, labelled as $\ulcorner$The birth of noble life$\lrcorner$ had a subgroup, (I felt the mystery and wonder of life), another group, $\ulcorner$After delivery, comfort and satisfaction$\lrcorner$ with the subgroup (I can bear to see the comfort and relief beyond pain) (C/S is better than vaginal delivery) (Very easy), the 3rd group, $\ulcorner$ I realized family friendship and support$\lrcorner$ with subgroup (Honorable, Magnificient) (I thank my parents ) (It's good to looking at my husband's support), and the 4th group, $\ulcorner$The birth of a healthy baby$\lrcorner$, with its subgroup, (baby looks pretty and healthy). 2. The negative responses were classified in eight categories and each category included subgroups. One group labelled as $\ulcorner$Fear$\lrcorner$, had subgroups of (Terrible, Horrible) (Shock) (Dread), another group, $\ulcorner$Tension$\lrcorner$, and its subgroup, (I became tense about stories heard before clinical practice), the 3rd group, $\ulcorner$surprise$\lrcorner$ and its subgroup (I was surprised at the delivery process), the 4th group, $\ulcorner$Power lessness$\lrcorner$ and its subgroup, (I watched the labor pain impatiently), the 5th group $\ulcorner$Apathy$\lrcorner$ ; and its subgroup, (I didn't feel the empathy for the labor pain of the pregnant women), the 6th group, $\ulcorner$Disgust$\lrcorner$ and its subgroup, (Disgust, Embarrassed), the 7th group, $\ulcorner$Inevitable destiny$\lrcorner$ and its subgroups (necessity of self-sacrifice and difficulty) (I accepted it as a women's destiny) (I can't do it), the last group, $\ulcorner$There seems to be trouble$\lrcorner$ and its subgroup, (It seems to have been a little too hard for mother and baby). Suggestions for further studies are as follows : 1. Nursing students should receive intensive education about $\ulcorner$The birth of noble life$\lrcorner$ $\ulcorner$After delivery, comfort and satisfaction$\lrcorner$ $\ulcorner$I realized family friendship and support$\lrcorner$ $\ulcorner$The birth of a healthy baby$\lrcorner$, so that a more positive attitude can be developed before clinical maternity nursing. 2. Nursing students should be given an orientation which is reality based and related clinical maternity nursing (using for A.V. Materials), so that they will not feel they tension, of the negative categories. 3. Nursing students should be received articles on Pain Relief Method, so that they will be prepared activie and positive in the clinical practice, and therefore they will not feel the powerlessness, of the negative categories. 4. F/U for responses of nursing students should be checked following clinical maternity nursing to evaluate the effects of the instruction.

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Time Resolution Improvement of MRI Temperature Monitoring Using Keyhole Method (Keyhole 방법을 이용한 MR 온도감시영상의 시간해상도 향상기법)

  • Han, Yong-Hee;Kim, Tae-Hyung;Chun, Song-I;Kim, Dong-Hyeuk;Lee, Kwang-Sig;Eun, Choong-Ki;Jun, Jae-Ryang;Mun, Chi-Woong
    • Investigative Magnetic Resonance Imaging
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    • v.13 no.1
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    • pp.31-39
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    • 2009
  • Purpose : This study proposes the keyhole method in order to improve the time resolution of the proton resonance frequency(PRF) MR temperature monitoring technique. The values of Root Mean Square (RMS) error of measured temperature value and Signal-to-Noise Ratio(SNR) obtained from the keyhole and full phase encoded temperature images were compared. Materials and Methods : The PRF method combined with GRE sequence was used to get MR temperature images using a clinical 1.5T MR scanner. It was conducted on the tissue-mimic 2% agarose gel phantom and swine's hock tissue. A MR compatible coaxial slot antenna driven by microwave power generator at 2.45GHz was used to heat the object in the magnetic bore for 5 minutes followed by a sequential acquisition of MR raw data during 10 minutes of cooling period. The acquired raw data were transferred to PC after then the keyhole images were reconstructed by taking the central part of K-space data with 128, 64, 32 and 16 phase encoding lines while the remaining peripheral parts were taken from the 1st reference raw data. The RMS errors were compared with the 256 full encoded self-reference temperature image while the SNR values were compared with the zero filling images. Results : As phase encoding number at the center part on the keyhole temperature images decreased to 128, 64, 32 and 16, the RMS errors of the measured temperature increased to 0.538, 0.712, 0.768 and 0.845$^{\circ}C$, meanwhile SNR values were maintained as the phase encoding number of keyhole part is reduced. Conclusion : This study shows that the keyhole technique is successfully applied to temperature monitoring procedure to increases the temporal resolution by standardizing the matrix size, thus maintained the SNR values. In future, it is expected to implement the MR real time thermal imaging using keyhole method which is able to reduce the scan time with minimal thermal variations.

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