• Title/Summary/Keyword: $T_d$

Search Result 13,210, Processing Time 0.057 seconds

Development of KD- Propeller Series using a New Blade Section (새로운 날개단면을 이용한 KD-프로펠러 씨리즈 개발)

  • J.T. Lee;M.C. Kim;J.W. Ahn;H.C. Kim
    • Journal of the Society of Naval Architects of Korea
    • /
    • v.28 no.2
    • /
    • pp.52-68
    • /
    • 1991
  • A new propeller series is developed using the newly developed blade section(KH18 section) which behaves better cavitation characteristics and higher lift-drag ratio at wide range of angle-of-attack. The pitch and camber distributions are disigned in order to have the same radial and chordwise loading distribution with the selected circumferentially averaged wake input. Since the geometries of the series propeller, such as chord length, thickness, skew and rate distribations, are selected by regression of the recent full scale propeller geometric data, the performance prediction of a propeller at preliminary design stage can be mure realistic. Number of blades of the series propellers is 4 and the expanded blade area ratios are 0.3, 0.45, 0.6 and 0.75. Mean pitch ratios are selected as 0.5, 0.65, 0.8, 0.75 and 1.1 for each expanded area ratio. The new propeller series is composed of 20 propellers and is named as KD(KRISO-DAEWOO) propeller series. Propeller open water tests are performed at the experimental towing tank, and the cavitation observation tests and fluctuating pressure measurements are carried out at the cavitation tunnel of KRISO. $B_{P}-\delta$ curves, which can be used to select the optimum propeller diameter at the preliminary design stage, are derived from a regression analysis of the propeller often water test results. The KD-cavitation chart is derived from the cavitation observation test results by choosing the local maximum lift coefficient and the local cavitation number as parameters. The caviy extent of a propeller can be predicted more accurately by using the KD-cavitation chart at a preliminary design stage, since it is derived from the results of the cavitation observation tests in the selected ship's wake, whereas the existing cavitation charts, such as the Burrill's cavitation chart, are derived from the test results in uniform flow.

  • PDF

Tie Spatial Structure of Ch'ang-ts'ai-ts'un Village A Case Study on a Rural Village of Korean Immigrants in Yen-pien Area of China (중국(中國) 연변지구(延邊地區) 조선족(朝鮮族)마을의 구성(構成) 룡정시 지신향 장재촌을 대상으로)

  • Lee, Kyu Sung
    • Journal of architectural history
    • /
    • v.3 no.1
    • /
    • pp.83-99
    • /
    • 1994
  • Ch'ang-Ts'al-Ts'un is a rural Village near Lung-jing City in Yen-pien Korean Autonomous Province of China. It was formed about 100 years ago by Korean Immigrants and has been developed maintaing the characteristics of traditional Korean architecture. Therefore investigating the spatial structure of this village is a meanigful work to confirm and explore one branch of Korean architecture. This study aims at analyzing the spatial structure of the village using direct data collected from the field work and indirect data from books and maps. The field work consists of on-the-site survey of the village layout, interviews of residents, observation notes and photography. Ch'ang-Ts'ai-Ts'un is located 360-370 m high above the sea level and at the side of a long valley. A river flows in the middle of the valley and relatively flat arable land exists at the both sides of the river. The location of the village related to the surrounding river and mountains suggests that the site of the village was chosen according to Feng-Shui, Chinese and Korean traditional architectural theory. The main direction of the house layouts is South-western. The village has been growing gradually until today. Therefore it is meaningful to make the village layout before Liberation(1946 A.D.) because the characteristics of Korean architecture prevailed more in that period. The area of the previous village is limited to the west side of the creek. New houses were later added to the east of the creek, forming a 'New Village'. Previously the village was composed of 3 small villages: Up, Middle and Down. Also the main access roads connecting the village with the neighboring villages were penetrating the village transversely. Presently the main access road comes to the village longitudinally from the main highway located in front of the village. The retrospective layout shows the existence of well-formed Territory, Places and Axes, thus suggesting a coherent Micro-cosmos. The boundary of imaginery territory perceived by present residents could be defined by linking conspicous outside places sorrounding the village such as Five-mountains, Front-mountain, Shin-dong village, Standing-rock, Rear-mountain and Myong-dong village. Inside the territory there are also the important places such as Bus-stop, Memorial tower of patriots, Road-maitenance building and the village itself. And inside it 5 transverse and 1 longitudinal axes exist in the form of river, roads and mountains. The perceived spatial structure of the village formed by Places, Axes and Territory is geometrical and well-balanced and suggests this village is fit for human settlement. The administrative area of the village is about 738 ha, 27 % of which is cultivated land and the rest is mountain area. Initially the village and surrounndings were covered with natural forest But the trees have been gradually cut down for building and warning houses, resulting in the present barren and artificial landscape with bare mountains and cultivated land. At present the area of the village occupied by houses is wedge-shaped, 600 m wide and 220 m deep in its maximum. The total area of the village is $122,175m^{2}$. The area and the rate of each sub-division arc as follow. 116 house-lots $91,465m^{2}$ (74.9 %) Land for public buildings and shops $2,980m^{2}$ (2.4 %) Roads $17,106m^{2}$ (14.0 %) Creek $1,356m^{2}$ (1.1 %) Vacant spaces and others $9,268m^{2}$ (7.6 %) TOTAL $122,175m^{2}$ (100.0 %) Each lot is fenced around with vertical wooden pannels 1.5-1.8 m high and each house is located to the backside of the lot. The open space of a lot is sub-divided into three areas using the same wooden fence: Front yard, Back yard and Access area. Front and back yards are generally used for crop-cultivation, the custom of which is rare in Korea. The number of lots is 116 and the average size of area is $694.7m^{2}$. Outdoor spaces in the village such as roads, vacant spaces, front yard of the cultural hall, front yard of shops and spacse around the creek are good 'behavioral settings' frequently used by residents for play, chatting, drinking and movie-watching. The road system of the village is net-shaped, having T-junctions in intersections. The road could be graded to 4 categories according to their functions: Access roads, Inner trunk roads, Connecting roads and Culs-de-sac. The total length of the road inside the village is 3,709 m and the average width is 4.6 m. The main direction of the road in the village is NNE-SSE and ESE-WNW, crossing with right angles. Conclusively, the spatial structure of Ch'ang-Ts'ai-Ts'un village consists of various components in different dimensions and these components form a coherent structure in each dimension. Therefore the village has a proper spatial structure meaningful and appropriate for human living.

  • PDF

Pharmacokinetics of ofloxacin in Patients with Multidrug-Resistant Tuberculosis (다제내성결핵 환자에서 ofloxacin의 약동학적 분석)

  • Park, Seung-Kyu;Yoon, Young-Ran;Lee, Woo-Chul;Jun, Hyung-Min;Shon, Ji-Hong;Kim, Kyoung-Ah;Park, Ji-Young;Shin, Jae-Gook
    • Tuberculosis and Respiratory Diseases
    • /
    • v.52 no.2
    • /
    • pp.128-136
    • /
    • 2002
  • Background: There are few studies that have reported on the pharmacokinetic(PK) disposition of fluoroquinolones in patients with multi-drug resistant tuberculosis(MDR-Tb), even though fluoroquinolones are frequently co-prescribed to those patients. In this study, the PK disposition of ofloxacin, a fluoroquinolone, was evaluated in patients with MD R -Tb. Methods: Twenty patients with MDR-Tb were given 2nd line Tb drugs including ofloxacin (300mg twice a day), prothionamide, cycloserine, para-aminosalicylic acid, kanamycin, and streptomycin. The patients were grouped according to their body mass index(BMI) as an index of emaciation (group A : 18.5$\leq$BMI <23, group B : BMI < 18.5). Blood samples were serially drawn and urine samples were collected upto 24 hours after the last dose of those drugs at steady state (over 1 month). The ofloxacin concentrations were determined using HPLC (High Performance Liquid Chromatography). Results: The AUC of ofloxacin in group B was greater than that in group A ($31.4{\pm}8.9{\mu}g/ml{\cdot}h$ vs. $24.1{\pm}6.2{\mu}g/ml{\cdot}h$)(Check the symbols), (p<0.05). The total clearance(Cl/F) of ofloxacin was $0.16{\pm}0.03$ L/h/kg in group A, and $0.14{\pm}0.03$ L/h/kg in group B. The half-lives of ofloxacin in two groups were similar (group A : $5.3{\pm}0.8$ hours, group B : $5.7{\pm}0.9$ hours). In addition, the other PK parameters in two groups were also similar. Conclusions: The pharmacokinetics of ofloxacin in patients with MDR-Tb appears to be comparable with those of normal subjects, and the extent of emaciation appears to have an influence on the pharmacokinetics of ofloxaicn in chronic debilitated MDR-Tb patients.

Factors Required to Sustain Pastoral Farming Systems and Forage Supply In Winter-Cold Zones in Canada (캐나다의 동계한냉지역에 있어서 초지개발과 조사료 공급의 활성화에 필요한 요인)

  • Kunelius, H.T.;Fraser, Joanna
    • Journal of The Korean Society of Grassland and Forage Science
    • /
    • v.12 no.3
    • /
    • pp.3-12
    • /
    • 1992
  • Forage grasses and legumes ar$\varepsilon$ the mam component of livestock diets in Canada. There are over 30 million ha of grassland in Canada and there is a large, undeveloped land base in fringe areas suitable for forage production. The short growing s season limits the grassland farming to the southern p parts of Canada. The win!er season is long and in most parts of Canada cold temperatures, fr$\varepsilon$ezmg, and thawing, and diseases exert sever$\varepsilon$ stress on overwintering forage plants. The development of persistent cultivars is essential for sustained production particularly in the fringe areas with short growmg s$\varepsilon$ason. The seasonality of dry matter production is a result of high growth rates in early summ$\varepsilon$r and low dry matter accumulation in late summer and fall. Innovative management practIces a and cultivars with improved regrowth capacity are n necessary to overcome such skewed production pattern and to extend effiectlVe grazmg season l Improved pasture production is an important part of reducing costs in livestock operations and remaining competitive. It is suggested that applying available technology would increase pasture productivity and reduce d$\varepsilon$pendence on stored feeds thus improving profitability of small producers in particeular. Reducing nutrient losses during harv$\varepsilon$stmg, s storage, and feeding is essential for improved production efficiency during confinement. The devclopment of low cost and labor saving methods of ensiling is critical for improved efficiency and profitability of forage based enterprises Livestock industries must respond to consumer preferences for low fat and cholesterol foods. Research and development of entire production systems is emphasized for dev$\varepsilon$loping viabl$\varepsilon$ enterprises. It is increasingly difficult to secure resources for r$\varepsilon$search, education, and extension, and alliane$\varepsilon$s and cooperation must expand among organizations with interests in forage based livestock systems.

  • PDF

Computerized Multiple 15-hue tests for Quantifying Color Vision Acuity (색각 능력의 정량적 평가를 위한 전산화된 다중 15-색상 배열 검사법)

  • Ko S.T.;Hong S.C.;Choi M.J.
    • Journal of Biomedical Engineering Research
    • /
    • v.21 no.3 s.61
    • /
    • pp.321-331
    • /
    • 2000
  • Multiple 15-hue tests were designed and implemented on a PC in the study so as to quickly and quantitatively evaluate color vision acuity. Difficulty of the test was control)ed by the value of CDBACC (color difference between adjacent color chips) calculated using a CIELAB formula. The multiple 15-hue tests consist of eight of the hue tests (test 3-10) and three of the basic color (red, green, blue) tests (test 11-13). The 15 colors used for the hue tests were specified by the 15 color coordinates that were located at a constant distance (d = 2. 3. 5. 7, 10, 20, 30. 40) from white reference in the CIE chromaticity coordinate system and were separated by a constant color difference (CDBACC = 0.75, 1.1, 1.8. 2.5. 3.5. 7.5. 11, 14) from the adjacent chips. The color coordinates for the 15 chips for the basic color tests were the same as those of the 15 points spaced equally by a constant color difference (6.87 for the green color test. 7.27 for the red color test, 7.86 for the blue color test) from the white reference along the axis of red, green and blue. Thirty normal subjects who were not color blind were taken to undergo the multiple 15-hue tests. It was observed that most of the subjects correctly arranged color chips for the tests with CDBACC greater than 5, whereas no one correctly answered for those with CDBACC less than 2. Rapid changes in the number of the subjects correctly arranged took place when CDBACC of the tests was between 2 and 4.5. In the basic color tests, unlike the hue tests having similar values of CDBACC, it was seen that the subjects arranged color chips even less correctly. It was found that JNCD (just noticeable color difference) - a measure of color vision acuity was about 3 in average for the subjects. The JNCD was chosen as the value of the CDBACC of the test for which about $50\%$ of the subjects failed to successfully arrange color chips. ERCCA (error rate of color chips arrangement) for the test with CDBACC the same as the JNCD was shown to be about $20\%$. It is expected that the multi 15-hue tests implemented on a PC in the study will be an economical tool to quickly and quantitatively evaluate color vision acuity and, accordingly, the tests can be used for early diagnosis to massive potential patients suffering from diseases (ex. diabetes, glaucoma) which may induce changes in color vision acuity.

  • PDF

The evaluation of clinical efficacy and longevity of home bleaching without combined application of In-office bleaching (자가미백술 단독사용시 임상적 효능 및 유지력 평가)

  • Shin, Byunk-Gyu;Yang, Sung-Eun
    • Restorative Dentistry and Endodontics
    • /
    • v.35 no.5
    • /
    • pp.387-394
    • /
    • 2010
  • Objectives: The purpose of this study was to evaluate the whitening efficacy and longevity of home bleaching. Materials and Methods: A total of 28 patients were divided into either experimental group (Opalescence F; 15% carbamide peroxide) or control group randomly. The patients in experimental group were instructed to wear individual trays applied with bleaching gel for 2 hours a day for 4 weeks. Any treatments weren't applied to the patients in control group. The color measurements of central incisors, lateral incisors & canines of upper and lower arch were recorded at base line, immediately after the finishment of treatmemt (4 weeks), 8 weeks and 12 weeks using Colorimeter (Chroma Meter, 2600d Konica Minolta co.) and Vitapan classical shade guide (Vita Zahnfabrik). Results: A significantly stronger color change was observed for overall teeth samples in experimental group immediately after treatment (at 4 weeks) compared to ones in control group (p < 0.05). There was also a significant difference between baseline and 8 weeks or 12 weeks separately though color rebouncing phenomenon occurred as time went by (p < 0.05). Conclusions: The clinical effecacy and longevity of home bleaching without combined application of in-office bleaching was observed through this experiment.

Effect of Dietary Glycine Betaine on Pork Qualities During Storage (Glycine betaine의 급여가 돈육의 품질에 미치는 영향)

  • Park, G.B.;Hur, S.J.;Yang, H.S.;Lee, J.I.;Kwck, S.J.;Lee, J.D.;Huh, N.E.;Kim, J.S.;Joo, S.T.
    • Journal of Animal Science and Technology
    • /
    • v.46 no.5
    • /
    • pp.821-832
    • /
    • 2004
  • A total of 80 pigs were used to investigate the effect of dietary glycine betaine(N,N,N-trimethylglycine) on pork quality during cold storage. About 70 kg pigs were randomly a1loted into one of four experimental diet groups(0%, 0.2%, 0.4% and 0.6% glycine betaine). Pigs were slaughtered at approximately 110 kg live weight, and pH, color(CIE $L^* a^* b^*$), shear force, sarcomere length, lipid oxidation and composition of fatty acid were measured in pork loin for 13 days of cold storage. The concentration of glycine betaine in pork loin was significantly increased(P<0.05) with increasing of glycine betaine level in diet. Pork loins from dietary betaine groups showed significantly higher muscle pH and lower CIE $b^*$ values compared to control group after 13 days of storage. There were significant differences in shear force values among pork loins from diet groups at 24 hrs postmortem. However, pork loins from control diet showed longer sarcomere length than those of dietary betaine groups. Dietary glycine betaine increased the ratio of saturated fatty acids and decreased unsaturated fatty acids in pork loins. Especially the ratios of linoleic and myristic acid were decreased with increasing dietary betaine level. However, dietary glycine betaine did not affect lipid oxidation (TSARS) and sensory evaluation during cold storage.

The Effects of Environment-Friendly Diets on the Growth Performance, Nutrient Digestibility, Fecal Excretion, Nitrogen Excretion and Emission Gases in Manure for Growing Pigs (환경친화적인 사료의 급여가 육성돈의 성장 능력, 영양소 소화율, 분 배설량, 분뇨내 질소배설량 및 악취 가스에 미치는 영향)

  • Yoo, J.S.;Cho, J.H.;Chen, Y.G.;Kim, H.J.;Wang, Q.;Hyun, Y.;Ko, T.G.;Park, C.S.;Kim, I.H.
    • Journal of Animal Science and Technology
    • /
    • v.49 no.4
    • /
    • pp.491-500
    • /
    • 2007
  • Two experiments were used to determine the effects of environment-friendly diets on growth performance, fecal excretion, nitrogen excretion and emission gases in manure for growing pigs. In experiment 1, ninety six crossed pigs(Landrace×Yorkshire×Duroc) were allocated into four treatments. Treatments were AME(adequate ME diet, 3,265 kcal/kg), LME(lower ME diet, 3,100 kcal/kg), LME 0.05(lower ME diet+α- galactosidase & β-mannanase 0.05%) and LME 0.10(lower ME diet+α-galactosidase & β-mannanase 0.10%). Pigs fed AME diet had lower ADFI(Average Daily Feed Intake) than pigs fed other diets(p<0.05). DM(Dry Matter) digestibility in pigs fed AME and LME 0.10 diets had greater than pigs fed LME diet(p<0.05). Energy digestibility is higher in pigs fed AME and LME 0.10 diets than other treatments(p<0.05). In experiment 2, twenty four crossbred pigs(33.71 kg average BW) were used in a 14-d metabolism experiment. The pigs were housed in individual cages equipped with plastic bed flooring. Treatments were CP(Crude protein) 18% without Bacillus sp., CP 18% diet+Bacillus sp. 0.05%, CP 14% without Bacillus sp. and CP 14% diet+Bacillus sp. 0.05%. Nitrogen intake was higher for CP 18% diets than CP 14% diets(p<0.05). DM, N(Nitrogen) and energy digestibility were affected by probiotics(p<0.05). With the high CP in diets, Energy and N digestibility, urine N percent, urine N excretion and total N excretion were increased significantly compared to low CP in diets(p<0.05). Among the treatments, DM and N digestibilities, feces N excretion, N absorption were decreased significantly(p<0.05), however, feces excretion, feces N, urine N percent, urine N excretion and total N excretion were increased significantly(p<0.05) when pigs fed without probiotics diets compare to pigs fed with probiotics diets. DM and N digestibility, feces excretion, feces N excretion, urine N percent, urine N excretion, total N excretion, N absorption and N adsorption ratio were CP×probiotic interactions in p<0.05. Ammonia(p<0.01) and H2S(p<0.05) in manure were lower in CP 14% diets than CP 18% diets. Also, ammonia and H2S in manure were CP×probiotic interactions in p<0.05. In conclusion, low energy and reduction of CP dietary added enzyme and probiotics improved nutrient digestibility and reduced odors emission in manure for growing pigs.

Research for Application of Interactive Data Broadcasting Service in DMB (DMB에서의 양방향 데어터방송 서비스도입에 관한 연구)

  • Kim, Jong-Geun;Choe, Seong-Jin;Lee, Seon-Hui
    • Broadcasting and Media Magazine
    • /
    • v.11 no.4
    • /
    • pp.104-117
    • /
    • 2006
  • In this Paper, we analyze the application of Interactive Data Broadcasting in DMB(Digital Multimedia Broadcasting) in the accordance with convergence of service and technology. With the acceleration of digital convergence in the Ubiquitous period substantial development of digital media technology and convergence of broadcasting and telecommunication industry are being witnessed. Consequently these results gave rise to newly combined-products such as DMB(Digital Multimedia Broadcasting), WCDMA(Wide-band code division multiple access), Wibro(Wireless Broadband Internet), IP-TV (Internet protocol TV) and HSDPA(High speed downlink packet access). The preparatory stage for the implementation of Interactive Data Broadcasting Service will be reached by the end of December, 2006. DMB is the first result of a successful convergence service between Broadcasting and Telecommunication in new media era. Multimedia technology and services are the core elements of DMB. The Data Broadcasting will not only offer various services of interactive information such News, Weather, Broadcasting Program etc, but also be linked with characteristic function of mobile phone such as calling and SMS(Short Message Service) via Return Channel.

Relationship Between Standardized Precipitation Index and Groundwater Levels: A Proposal for Establishment of Drought Index Wells (표준강수지수와 지하수위의 상관성 평가 및 가뭄관측정 설치 방안 고찰)

  • Kim Gyoo-Bum;Yun Han-Heum;Kim Dae-Ho
    • Journal of Soil and Groundwater Environment
    • /
    • v.11 no.3
    • /
    • pp.31-42
    • /
    • 2006
  • Drought indices, such as PDSI (palmer Drought Severity Index), SWSI (Surface Water Supply Index) and SPI (Standardized Precipitation Index), have been developed to assess and forecast an intensity of drought. To find the applicability of groundwater level data to a drought assessment, a correlation analysis between SPI and groundwater levels was conducted for each time series at a drought season in 2001. The comparative results between SPI and groundwater levels of shallow wells of three national groundwater monitoring stations, Chungju Gageum, Yangpyung Gaegun, and Yeongju Munjeong, show that these two factors are highly correlated. In case of SPI with a duration of 1 month, cross-correlation coefficients between two factors are 0.843 at Chungju Gageum, 0.825 at Yangpyung Gaegun, and 0.737 at Yeongju Munjeong. The time lag between peak values of two factors is nearly zero in case of SPI with a duration of 1 month, which means that groundwater level fluctuation is similar to SPI values. Moreover, in case of SPI with a duration of 3 month, it is found that groundwater level can be a leading indicator to predict the SPI values I week later. Some of the national groundwater monitoring stations can be designated as DIW (Drought Index Well) based on the detailed survey of site characteristics and also new DIWs need to be drilled to assess and forecast the drought in this country.