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Mechanical Design Fabrication and Test of a Biomimetic Fish Robot Using LIPCA as an Artificial Muscle (인공근육형 LIPCA를 이용한 물고기 모방 로봇의 설계, 제작 및 실험)

  • Heo, Seok;Wiguna, T.;Goo, Nam-Seo;Park, Hoon-Cheol
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.31 no.1 s.256
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    • pp.36-42
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    • 2007
  • This paper presents mechanical design, fabrication and test of a biomimetic fish robot actuated by a unimorph piezoceramic actuator, LIPCA(Lightweight Piezo-Composite curved Actuator.) We have designed a linkage mechanism that can convert bending motion of the LIPCA into the caudal fin movement. This linkage system consists of a rack-pinion system and four-bar linkage. Four types of artificial caudal fins that resemble caudal fin shapes of ostraciiform subcarangiform, carangiform, and thunniform fish, respectively, are attached to the posterior part of the robotic fish. The swimming test under 300 $V_{pp}$ input with 0.6 Hz to 1.2 Hz frequency was conducted to investigate effect of tail beat frequency and shape of caudal fin on the swimming speed of the robotic fish. At the frequency of 0.9 Hz, the maximum swimming speeds of 1.632 cm/s, 1.776 cm/s, 1.612 cm/s and 1.51 cm/s were reached for fish robots with ostraciiform, subcarangiform carangiform and thunniform caudal fins, respectively. The Strouhal number, which means the ratio between unsteady force and inertia force, or a measure of thrust efficiency, was calculated in order to examine thrust performance of the present biomimetic fish robot. The calculated Strouhal numbers show that the present robotic fish does not fall into the performance range of a fast swimming robot.

Facial reanimation using the hypoglossal nerve and ansa cervicalis: a short-term retrospective analysis of surgical outcomes

  • Koo, Won Young;Park, Seong Oh;Ahn, Hee Chang;Ryu, Soo Rack
    • Archives of Craniofacial Surgery
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    • v.22 no.6
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    • pp.303-309
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    • 2021
  • Background: Transferring the hypoglossal nerve to the facial nerve using an end-to-end method is very effective for improving facial motor function. However, this technique may result in hemitongue atrophy. The ansa cervicalis, which arises from the cervical plexus, is also used for facial reanimation. We retrospectively reviewed cases where facial reanimation was performed using the ansa cervicalis to overcome the shortcomings of existing techniques of hypoglossal nerve transfer. Methods: The records of 15 patients who underwent hypoglossal nerve transfer were retrospectively reviewed. Three methods were used: facial reanimation with hypoglossal nerve transfer (group 1), facial nerve reanimation using the ansa cervicalis (group 2), and sural nerve interposition grafting between the hypoglossal nerve and facial nerve (group 3). In group 1, the ansa cervicalis was coapted to neurotize the distal stump of the hypoglossal nerve in a subset of patients. Clinical outcomes were evaluated using the House-Brackmann (H-B) grading system and Emotrics software. Results: All patients in group 1 (n= 4) achieved H-B grade IV facial function and showed improvements in the oral commissure angle at rest (preoperative vs. postoperative difference, 6.48° ± 0.77°) and while smiling (13.88° ± 2.00°). In groups 2 and 3, the oral commissure angle slightly improved at rest (group 2: 0.95° ± 0.53°, group 3: 1.35° ± 1.02°) and while smiling (group 2: 2.06° ± 0.67°, group 3: 1.23° ± 0.56°). In group 1, reduced tongue morbidity was found in patients who underwent ansa cervicalis transfer. Conclusion: Facial reanimation with hypoglossal nerve transfer, in combination with hypoglossal nerve neurotization using the ansa cervicalis for complete facial palsy patients, might enable favorable facial reanimation outcomes and reduce tongue morbidity. Facial reanimation using the ansa cervicalis or sural nerve for incomplete facial palsy patients did not lead to remarkable improvements, but it warrants further investigation.

A Study on Applying Novel Reverse N-Gram for Construction of Natural Language Processing Dictionary for Healthcare Big Data Analysis (헬스케어 분야 빅데이터 분석을 위한 개체명 사전구축에 새로운 역 N-Gram 적용 연구)

  • KyungHyun Lee;RackJune Baek;WooSu Kim
    • The Journal of the Convergence on Culture Technology
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    • v.10 no.3
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    • pp.391-396
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    • 2024
  • This study proposes a novel reverse N-Gram approach to overcome the limitations of traditional N-Gram methods and enhance performance in building an entity dictionary specialized for the healthcare sector. The proposed reverse N-Gram technique allows for more precise analysis and processing of the complex linguistic features of healthcare-related big data. To verify the efficiency of the proposed method, big data on healthcare and digital health announced during the Consumer Electronics Show (CES) held each January was collected. Using the Python programming language, 2,185 news titles and summaries mentioned from January 1 to 31 in 2010 and from January 1 to 31 in 2024 were preprocessed with the new reverse N-Gram method. This resulted in the stable construction of a dictionary for natural language processing in the healthcare field.

An Analysis of the Realtionship between Menopausal Symptoms and Depression (중년 여성의 갱년기 증상과 우울에 관한 연구)

  • Kwon, Sook-Hee;Kim, Yung-Ja;Moon, Guil-Nam;Kim, In-Soon;Park, Geum-Ja;Park, Choon-Hwa;Baim, Jeung-Yee;Sing, Ae-Ri;Yoe, Jung-Hee;Chung, Eun-Soon;Jung, Hyang-Mi
    • Women's Health Nursing
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    • v.2 no.2
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    • pp.270-283
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    • 1996
  • This study was done for the purpose of analyzing the relationship between menopausal symptoms and depression. Data were collected by a questionnaire from November 28 to December 30, 1995. The subjects were 134 women between 40-61 years of age. The instruments used for this study were The Menopausal symptom scale by Neugartom and Depression scale by Zung. The results of the study were as follows. 1. Mean score of menopausal symptoms was 1.59. Mean score orders of experienced symptoms were "Rack pain and joint pain"(2.02), "General weakness"(1.98), "Nervousness"(1.96). The most serious menopausal symptom was psychosomatic symptom.(1.88) Total score orders of experienced symptoms was 27.9 and over 90.3% of women complained menopausal symptom. 2. Mean score orders of depression was 39.13. It was normal range of depression. 85.1% of the women were normal range of depression and 14.2% of women mild depression. 3. The relationship between menopausal symptoms and depression was statistically significant(r=0.5307, p=0.000). When the relationship among three dimensions of menopausal symptoms were explored the psychosomatic symptom(r=0.4090, P=0.000), Physical symptom(r=0.319, P=0.000), Physical symptom(r=0.319, P=0.000) were statistically significant. 4. General characteristic variables were significantly related to the level of menopausal symptoms as follows ; environment of living(F=2.89, p=0.038), religion(F=4.18, P=0.007), times of birth(F=2.66, p=0.043). The analysis of this study have implication for management of middle aged women's health, to solve the nursing problems, and to prevent and relieve climacteric symptoms.

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Effect of Plant Growth Regulators on the Adventitious Root Formation from Bupleurum falcatum Callus (생장조절물질(生長調節物質)이 시호(柴胡) 캘러스의 부정근(不定根) 형성(形成)에 미치는 영향(影響))

  • Seong, Rack-Seon;Cho, Duck-Yee;Soh, Woong-Young
    • Korean Journal of Medicinal Crop Science
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    • v.5 no.1
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    • pp.7-13
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    • 1997
  • Calli induced from the leaf segment of Bupleurum falcatum were cultured on Mu-rashige and Skoog's(MS) medium supplemented with 2, 4-D, IBA, IAA and NAA of 0.1 mg/l , The induction of adventitious roots from callus was the best in MS medium supplemented with 0.1 mg/l 2, 4-D and the lateral root was the same. The pretreatment of 0.1 mg/l 2, 4-D for 120 hours was most effective for the formation and grwoth of adventitious roots. The number of adventitious roots per micro callus pre-treated with 0.1 mg/l 2, 4- D was 5. 3 which was the highest level. The callus subcultured for 4 weeks were best for the adventitious root formation. The callus subcultured for more than 4 weeks decreased the adventitious root formation and turned to brown in color.

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Adsorption Mechanism of Alkyl Ketones on Cation Supported by Layer Silicate. Link Formation of Hydroxyl Group (Layer Silicate에 지지된 양이온상에서 일어나는 Alkyl Ketones의 흡착기구. 水酸基의 Link 形成理論)

  • Jong Taik Kim;Jong Rack Sohn
    • Journal of the Korean Chemical Society
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    • v.17 no.4
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    • pp.247-255
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    • 1973
  • The self supported film specimen of Wyoming montmorillonite as a layer silicate saturated by cations,$Li^{+},\;Na^{+},\;K^{+},\;Ca^{2+},\;Ni^{2+},\;Al^{3+}$and$F^{3+}$ were allowed to contact acetone, methyl-ethyl ketone and diethyl ketone within the heatable gas cell. The i.r. spectra between $4000{\sim}1200cm^{-1}$ at different pressures of adsorbates indicated bond formation through carbonyl oxygen. Two types of carbonyl bond shift with maxima at $1713cm^{-1}$ and $1690cm^{-1}$ are attributed as coordinate bond formation of carbonyl with either surface hydroxyl or cationic hydroxyl group. The intensity of the vOH was analyzed and resonance form of cationic hydroxyl was proposed as an adsorption site. The tendency to form coordinate bond was in good agreement with calculated formal charge of carbonyl oxygen in an increasing order, acetone < methyl-ethyl ketone < diethyl ketone. As an additional mechanism of adsorption, weak hydrogen bonding of methyl hydrogen with surface oxygen was observed.

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Numerical Analysis of Combustion and Heat Transfer of Domestic Gas Boiler Equipped with 2-stage Heat Exchanger (수치해법을 이용한 2단 열교환기 장착 가정용 보일러 연소실의 연소 및 열전달 특성 해석)

  • Kang, Seung-Kyu;Choi, Kyoung-Suhk;Kwon, Jeong-Rack
    • Journal of the Korean Institute of Gas
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    • v.14 no.5
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    • pp.1-6
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    • 2010
  • In this work, a numerical investigation is performed for the combustion chamber of domestic gas boiler with 1-stage and 2-stage heat exchangers. The fluid flow and heat transfer performance is simulated with a structure change of heat exchanger. The numerical solution shows that the heat transfer of the 2-stage heat exchanger is about 24% higher than that of the 1-stage heat exchanger, while the pressure loss of the 2-stage heat exchanger increases. The temperature of combustion chamber with 2-stage heat exchanger is lower than that of 1-stage. This effect reduces thermal NOx with decrease of high temperature staying time of the combustion gas.

Morphological Development and Reproductive Behavior of Hedgehog Seahorse Hippocampus spinosissimus (Teleostei: Syngnathidae) (Hedgehog Seahorse (Hippocampus spinosissimus)의 산출습성 및 형태발달)

  • KANG Su Youn;KOH Jeong Rack;JEONG Seung Beom;KIM Suam
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.38 no.5
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    • pp.298-303
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    • 2005
  • This study described the reproductive behavior and the morphological development of the larvae and juvenile of the hedgehog seahorse (Hippocampus spinosissimus). Larvae released from male seahorse were reared for 30 days in the laboratory. At the birth, the small flap-like mouth and anus of the yolk-sac larvae were open, and the yolk was completely absorbed within 1 day. The size of newborn larvae ranged 7.01-13.19mm (mean $9.26\pm1.9mm$, n=9) in TL (total length). The larvae had 15-16 pectoral fin rays and 19 dorsal fin rays, but 4 anal fin rays were not completely developed. The larval size ranged 13.38-14.38 mm (mean $13.96\pm0.3mm$, n=6) in TL at 1 day after release, and they had 17 pectoral fin rays, 20 dorsal fin rays and 4 anal fin rays when the larvae reached the juvenile stage. Juvenile size ranged 14.98-16.42mm (mean $15.84\pm0.5mm$, n=5) in TL at 3 days after release, and 1, 4, 6, 8 trunk spines extended quickly. Terminal part of the coronet became a four-forked wedge shape concurrently. Juvenile became 23.25mm (n=l) in TL after 15 days and all 11 trunk rings was connected completely. After 20 days, the juveniles were 24.66-28.65mm (mean $27.26\pm1.6mm$, n=5) in TL, and many melanophores appeared in integument. In the eye lenses, 5-6 lusters were formed. After 30 days, the juveniles were 26.78-28.26 mm (mean $27.36\pm0mm$, n=4)in TL and 8-9 lusters appeared on the eye lenses. Coronet terminal part developed to a five-forked crown-shape completely.

The Study on the Analysis of Marine Accidents and Preventive Measures (해양사고의 분석과 방지대책에 관한 연구)

  • SEO, Man-Seok;BAE, Seok-Je
    • Journal of Fisheries and Marine Sciences Education
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    • v.14 no.2
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    • pp.149-160
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    • 2002
  • I have been analyzed the marine accidents during 10years(1992~2001) based on the maritime inquire court decision, the results were as follows: 1. The rate of accident occuring were showed fishing boat(69.9%), freighter(12.3%), tanker(4.3%), tug boat(3.8%), passenger boat(2.1%) by the usage. 2. The marine accident had been showed operational fault(67.3%), mishandling of engine equipment(21.7%), meteorological condition, etc(11%) by the reason, most accidents had been occured by the operator fault and rack of experience. 3. The marine accidents had been showed damage of hull and engine(27.5%), collision(24%), foundering(11.3%), fire(3.9%), agrounding(10%), by the kind of accidents. 4. The accidents had been occured (74.6%) at the coastal sea, harbour and (25.4%) at the open sea by the sectors. The accidents of the vessel less than 500ton were much increased (54.3%) also, The accidents were much occured at the time between 0400~0800 hours by the time.

Simultaneous Determination and Recognition Analysis of Coumarins in Angelica decursiva and Peucedanum praeruptorum by HPLC-DAD

  • Kim, Hye Mi;Jeong, Su Yang;Kim, Sun Min;Lee, Kyu Ha;Kim, Jong Hwan;Seong, Rack Seon
    • Natural Product Sciences
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    • v.22 no.3
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    • pp.162-167
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    • 2016
  • Peucedani Radix is the root of Angelica decursiva Franchet et Savatier (=Peucedanum decursivum Maximowicz) or Peucedanum praeruptorum Dunn in several Asian countries. The coumarins contained in Peucedani Radix were quantitatively analyzed using HPLC-DAD to develop a simultaneous determination for the quality control of A. decursiva and P. praeruptorum. For quantitative analysis, four major coumarins contained in these medicinal plants were assessed. Nodakenin (1), nodakenetin (2), praeruptorin A (3), and praeruptorin B (4) were separated with a Phenomenex Luna C18 column ($5{\mu}m$, $4.6{\times}250mm$) under the gradient conditions using distilled water with 0.1% phosphoric acid and acetonitrile with 0.1% phosphoric acid as the mobile phase, at a flow rate of 1.0 ml/min and a detection wavelength of 330 nm. This method was fully validated for linearity, accuracy, precision, recovery, and limit of detection and quantification. As a result, A. decursiva and P. praeruptorum were clearly classified by the quantification of four major coumarins in extracts. Also, the pattern recognition analysis based on HPLC indicates that all of the samples were largely clustered into two groups. Therefore, it is possible to distinguish between A. decursiva and P. praeruptorum and contribute to quality control.