• Title/Summary/Keyword: Cross-type

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Fabrication and Performance Demonstration of the 20kW Class Inverted-type Cross-flow Turbine Based on Computational Fluid Dynamics Analysis (전산유체역학 해석에 기반한 20kW급 도립형 횡류수차의 제작 및 성능 실증)

  • Ham, Sangwoo;Choi, Ji-Woong;Jeong, Changho;Kim, Taeyun;Choi, Sangin;Jin, Glenn Young;Lee, Jeong Wan;Ha, Hojin
    • Journal of the Korean Society of Manufacturing Process Engineers
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    • v.20 no.2
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    • pp.107-119
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    • 2021
  • The cross-flow turbine is one of the most famous and widely used hydraulic power systems for a long time. The cross-flow turbine is especially popular in many countries and remote regions where off-grided because of its many benefits such as low cost, high efficiency at low head, simple structure, and easy maintenance. However, most modern turbines, including the cross-flow turbine, are unsuitable for the ultra-low head situation, known as less than 3m water head or zero head with over 0.5m/s flow velocity. In this study, we demonstrated a 20kW class inverted-type cross-flow turbine's performance. First, we reevaluated our previous studies and introduced how to design the inverted-type cross-flow turbine. Secondly, we fabricated the 20kW class inverted-type cross-flow turbine for the performance test. And then, we designed a testbed and installed the turbine system in the demonstration facility. In the end, we compare the demonstration with its previous CFD results. The comparing result shows that both CFD and real model fitted on guide vane angle at 10 degrees. At the demonstration, we achieved 42% turbine efficiency at runner speed 125 RPM.

Analysis of cross sections and silhouette in body shape according to girdle worn using 3D body scanner (3차원 인체스캐너를 이용한 거들 착용에 따른 인체 형상 단면도와 실루엣 변화 분석)

  • Lim, Ho-Sun;Chun, Jongsuk
    • The Research Journal of the Costume Culture
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    • v.23 no.2
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    • pp.242-253
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    • 2015
  • The aim of this study was to use a 3D human body scanner to analyze the cross section of different body parts when a girdle is worn. Two types of girdles were selected as experimental garments: a standard type girdle (Garment A) and a high-waist type girdle (Garment B). Their sizes were 88 (S) and 94 (M). Ten female subjects in their twenties who wear girdles sizes 88 (S) and 94 (M) participated the experiment. Their bodies were scanned three times with the 3D human body scanner, before and after wearing experimental girdles. The data were collected by overlapping the cross sections of the 3D scanned body shape data. The space length was measured from the overlapped cross sections. The results show that human body silhouette are changed after wearing the compression type garments and the amount and place of the body change is different by style of garments. First, the waist girth shape became rounder. Second, there was a definite difference in space amount at abdomen girth between two types of girdle. The abdomen area was pushed toward the front after wearing the standard type girdle (A). The high-waist type girdle (B) pushed abdomen area toward the back. Third, there was clear difference at the hip area after wearing two types of girdle. The hip area pushed toward the front with the standard type girdle (A) and pushed toward the back with the high-waist type girdle (B).

Study on torso body types of adult males over 178cm tall (178cm 이상의 키 큰 성인남성에 대한 체간부 체형 유형화 연구)

  • Kim, Min-jung
    • The Research Journal of the Costume Culture
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    • v.30 no.5
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    • pp.675-688
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    • 2022
  • The purpose of this study is to analyze the body type characteristics of tall adult men aged 20 to 69 years to present base material on body dimensions for men's clothing companies. The research method comprised statistical analysis of 3D measurements after selecting items from the 8th Korean human body size survey related to the torso body types of 495 adult men who were at least 178cm tall. As a result, six factors were extracted, and the total explanatory variable of the entire factor was shown to be 80.499%. As a result of cluster analysis using this as an independent variable, three types were derived: Type 1, "a normal body type with an oval cross-sectional shape" (37.6%), with a larger vertical size and an oval chest cross-sectional shape compared to other types; Type 2: a "cylindrical thick body shape" (31.1%), which is the first stage of BMI obesity, with narrow shoulders and a cylindrical shape with a round cross-section; Type 3, "a body shape with broad shoulders and developed chest parts" (31.3%), with a horizontal size similar to Type 2 above the waist, but similar to Type 1 below. The results of this study are expected to be used as a basis for a clothing dimension system and clothing development for tall men reflecting the characteristics of the torso.

Design of the recuperator for the gas turbine/fuel cell hybrid power generating system (가스터빈/연료전지 혼합발전 시스템의 열교환기 설계)

  • Kwak, Jae-Su;Yang, Soo-Seok;Lee, Dae-Sung
    • Proceedings of the KSME Conference
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    • 2004.04a
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    • pp.2105-2110
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    • 2004
  • Plate-fin type recuperators for the gas turbine/fuel cell hybrid power generating system were designed using commercial design software, MUSE. Heat transfer efficiency and total pressure drop in the recuperator were calculated to confirm required recuperator performance. Both counter flow and cross flow type plate-fin recuperators were designed. Results show that the counter flow type has higher efficiency and short core length, but the cross flow type is simpler to construct because the cross flow type does not need additional distributors. Two or three headers for the each recuperator core will be designed and tested to evaluate best header design. The designed recuperators and headers which will be designed later will be constructed, tested, and used in gas turbine/fuel cell hybrid power generating system.

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Effect of Periodic Walking on the Type II Muscle of Growing Suspended Rats (주기적인 보행이 성장하는 어린뒷다리부유쥐의 Type II 근육에 미치는 효과)

  • 최명애
    • Journal of Korean Academy of Nursing
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    • v.26 no.2
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    • pp.271-280
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    • 1996
  • The purpose of this study was to determine the effect of periodic walking during hindlimb suspension on the mass, relative weight, fiber type distribution and cross-sectional area of Type I and II fibers in the developing Type II plantaris muscle. To examine the effectiveness of periodic walking on mass and fiber size, the hindlimbs of young female Wistar rats were suspended (HS group) and half of these rats walked on a treadmill for 45 min/day(15 min every 4 hours) at 5 meters/min at a 15 degree grade(HS-W group) After seven days of hindlimb suspension, the plantaris muscle wet weight was 28.40% significantly smaller(P<0.005) and relative plantaris muscle weight was 26.97% smaller compared with those of control rats(P<0.05). The plantaris muscle wet weight and the relative plantaris muscle weight increased by 46.60% and 49.23% respectively with periodic walking, moreover. the plantaris muscle wet weight and the relative plantaris muscle weight of the HS-W rats recovered to the level of the control rats. No change was observed in fiber type percentage of the developing plantaris muscle following one week of hindlimb suspension or periodic walking during hindlimb suspension. Type I and II fiber cross-sectional areas of the developing plantaris muscle were 42.51% and 43. 68% lower in the HS group than in the control group(p<0.0001), Type I and II fiber cross-sectional areas of the developing plantaris were 30.82% and 45.97% greater in the HS-W group than in the HS group(p<0.0001), whereas Type I and II fiber cross-sectional area of HS-W group were less than those of the control group(P<0.0001) The results suggest that periodic walking can attenuate developing plantaris muscle atrophy induced by hindlimb suspension.

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Cross-Model Effect of Model Types, Product Gender Identity and Message Appeal Type (모델유형과 제품의 성 정체성 그리고 메시지 소구에 따른 크로스 광고모델 효과)

  • Kim, Eun-Hee;Yu, Seung Yeob
    • Journal of Digital Convergence
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    • v.12 no.6
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    • pp.105-114
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    • 2014
  • This study has recently been issued to businesses and consumers who examined the effects of cross-advertising model. Experimental design, the model type (2) ${\times}$ sexuality products (2) ${\times}$ advertising message appeal form (2) is a factorial design. The results are as follows. First, the advertising model, based on the type of cognitive response to advertising than the general model of cross-recall index was higher model. Second, the product of gender identity in response to what the advertising product for women than men was higher index of product recalls. Third, the ad attention model ANOVA results for each type of message, the main effect of appeal type was identified. In addition, the type and model of sexual identity, and message appeal type in the type of model interaction effects were found. Finally, the model-product analysis of goodness of fit, the model type and sexual identity and appeal type messages of main effect were identified. The result is more efficient advertising effect model strategies for promoting meaningful results, it is meant to be confirmed.

Performance and Internal Flow of a Cross-Flow Type Hydro Turbine for Wave Power Generation (파력발전용 횡류형 수력터빈의 성능 및 내부유동)

  • Choi, Young-Do;Cho, Young-Jin;Kim, You-Taek;Lee, Young-Ho
    • The KSFM Journal of Fluid Machinery
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    • v.11 no.3
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    • pp.22-29
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    • 2008
  • Clean and renewable energy technologies using ocean energy give us non-polluting alternatives to fossil and nuclear-fueled power plants to meet establishment of countermeasures against the global warming and growing demand for electrical energy. Among the ocean energy resources, wave power takes a growing interest because of its enormous amount of potential energy in the world. Therefore, various types of wave power conversion system to capture the energy of ocean waves have been developed. However, suitable turbine type is not normalized yet because of relatively low efficiency of the turbine systems. The purpose of this study is to investigate the internal flow and performance characteristics of a cross-flow type hydro turbine, which will be built in a caisson for wave power generation. Numerical simulation using a commercial CFD code is conducted to clarify the effects of the turbine rotation speed and flow rate variation on the turbine characteristics. The results show that the output power of the cross-flow type hydro turbine with symmetric nozzle shape is obtained mainly from Stage 2. Turbine inlet configuration should be designed to obtain large amount of flow rate because the static pressure and absolute tangential velocity are influenced considerably by inlet flow rate.

Comparison of Hypertrophic Effects of Low-Intensity Exercise on Rat Hindlimb Muscles between Every Other Day Exercise and Everyday Exercise (저강도 격일 운동과 매일 운동이 쥐 뒷다리근에 미치는 근 비대 효과 비교)

  • Choe, Myoung-Ae;Go, Jong-Jin;Kwak, Hyun-Kyung;Baek, Ji-Hyun;Jung, Jin-Yung;Song, Yeon-Jeong;An, Gyeong-Ju
    • Journal of Korean Biological Nursing Science
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    • v.13 no.1
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    • pp.1-7
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    • 2011
  • Purpose: The purpose of this study was to compare the hypertrophic effects of low-intensity exercise on weight, myofibrillar protein content and Type I, II fiber cross-sectional area of hindlimb muscles of rats between every other day exercise and every day exercise. Methods: Adult male Sprague-Dawley rats were assigned to 1 of 3 groups: control group (C, n=6), experimental group 1 (E1, n=7) and experimental group 2 (E2, n=7). Rats in E1 group had 7 sessions (every other day) and those in E2 group had 14 sessions (every day) of exercise in which they ran on a treadmill for 30 min/day at 10 m/min. Results: Muscle weight, cross-sectional area of type I fiber and myofibrillar protein content of soleus and myofibrillar protein content of plantaris in E1 group, and myofibrillar protein content of soleus and cross-sectional area of type I fiber of plantaris in E2 group were greater than those in C group. Cross-sectional area of type I fiber of soleus of E1 group was higher than E2 group while cross-sectional area of type I fiber of plantaris of E2 group was higher than E1 group. Conclusion: Hypertrophy of hindlimb muscles occurs from every other day exercise similar to every day exercise.

A Study on the Development of Cross-flow Type Vertical Axis Wind Turbine (횡류형 수직축 풍력터빈 개발에 관한 연구)

  • Hwang, Yeong-Cheol;Choi, Young-Do;Kim, Ill-Soo;Lee, Young-Ho
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.493-493
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    • 2009
  • Recently, small vertical axis wind turbine attracts attention because of its clean, renewable and abundant energy resources to develop. Therefore, a cross-flow type wind turbine is proposed for small wind turbine development in this study because the turbine has relatively simple structure and high possibility of applying to small wind turbine. The purpose of this study is to investigate the effect of the turbine‘s structural configuration on the performance and internal flow characteristics of the cross-flow turbine model using CFD analysis. The results show that guide nozzle should be adopted to improve the performance of the turbine. Optimization of the nozzle shape will be key-importance for the high performance of the turbine.

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Cross Type Domain in Exchange-Coupled NiO/NiFe Bilayers

  • Hwang, D.G;Kim, J.K;Lee, S.S;Gomez, R.D
    • Journal of Magnetics
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    • v.7 no.1
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    • pp.9-13
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    • 2002
  • The dependences of microscopic magnetic domain on film thickness in unidirectional and isotropic exchange-coupled NiO/NiFe bilayers were investigated by magnetic force microscopy to better understand for exchange biasing. As NiO thickness increases, microscopic domain structure of unidirectional biased film changed to smaller and more complicated domains. However, for isotropic-coupled film a new cross type domain appeared with out-of plane magnetization orientation. The density of the cross domain is proportional to exchange biasing fields and the fact that the domain was originated by the strongest exchange coupling region was confirmed from the dynamic domain configuration during a magnetization cycle.