• Title/Summary/Keyword: unit of mass

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Mass Spectrometry of Dammarane Triterpenoids (Dammarane계(係) Triterpenoid의 질량분광분석(質量分光分析))

  • Han, Byung-Hoon;Kim, Jae-Hoon;Chi, Hyung-Joon
    • Korean Journal of Pharmacognosy
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    • v.10 no.2
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    • pp.55-59
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    • 1979
  • Mass spectra of the dammarane triterpenes having open side chain and $C_{20}-C_{25}-epoxy$ side chain were measured. Principal fragment ions were assigned and plausible mechanisms for the formation of the fragment ions were proposed. In general, the triter-penoids of $C_{20}-C_{25}-epoxy$ side chain. produce $h_{1}-species$ fragment ions by the deletion of side chain at $C_{20}-C_{22}$ bond and open side chain triterpenoids produce $h_{2}$ species fragmentions whose mass numbers are higher by two mass unit than those of $h_{1}$ species. The mass number of h species fragment ions will serve as the diagnostic tool for the elucidation of side chain structure of tetracyclic triterpenoids.

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A Study on the Spatial Characteristics of the Multi-housing Units in Seoul and Kyung-gi Area - Focused on the Unit Size of over $165m^2$- (최근 분양된 수도권 공동주택 단위세대의 공간계획 특성에 관한 연구 - 전용면적 $165m^2$ 이상의 대형규모를 중심으로 -)

  • Kim, Mi-Kyoung
    • Korean Institute of Interior Design Journal
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    • v.16 no.6
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    • pp.116-124
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    • 2007
  • The purpose of this study is to find out the spatial characteristics of the multi-housing units in Seoul and Kyung-gi area since 2006. Literature review and content analysis were used for this study and 82units of the big size over $165m^2$ were analyzed to review such design characteristics as spatial composition, layout and linkage. Through this study, the following conclusions have been reached; 1) Most unit plans had 4LDK and 3bath types including family room as a public space. This results shows that family-room and bathroom has recently become more important than number of rooms in multi-housing units planning. 2) Diversity of plan figures such as mass-mixing, mass-separation and polygons(L, V-type)was showed in most unit plan, breaking from the standardized forms of box types. 3) Intermediated spaces such as foyers and halls in entrance zone were planned and sub-entrance into kitchen were planned for the various types of circulation and work-efficiency. Cases had private space separated from public space, the dispersion of rooms with the increase of connection by corridors, L-DK meaning the living room isolated from the dining and kitchen, partially located living room for a view in area distribution. The spatial planning of master-zone mostly consists of the types of two-rooms and an entry into a foyer(library, dress-powder room, bathroom and master bedroom). This study has a significant meaning on grasping current trend in Korean multi-housing and to provide information for future direction on housing-unit design.

Injector Head Design of 170tonf UDMH-LOX Liquid Rocket Engine (추력 170톤급 UDMH-LOX 계열 액체로켓엔진의 인젝터 헤드 설계)

  • Lim, Seok-Hee;Gostsev, V.
    • Proceedings of the Korean Society of Propulsion Engineers Conference
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    • 2006.11a
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    • pp.207-210
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    • 2006
  • Injector is one of the most important elements in Liquid rocket Engine design, and how to arrange these injectors on the head determines the engine performance. In this study, when the swirl injectors are used for the 1st designing of injector head of 170 tonf UDMH-LOX as the propellant of LRE, a distribution relation of the mass flow rate per unit area was calculated from the function of ${\Phi}$, which is related with the mass flow rate characteristics of swirl injector. And the combustion characteristics by circumferential axis were estimated using this relation under the consideration of combustion core and film cooling area.

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Mass Transfer of Gas-Liquid in Agitated Vessel Using Wire Gauge Impeller (금망임펠러를 이용한 교반조에서의 기-액 물질이동)

  • Lee, Young-Sei
    • Journal of the Korean Society of Industry Convergence
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    • v.11 no.1
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    • pp.19-26
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    • 2008
  • The gas-liquid mass transfer volumetric coefficients in gas-liquid agitated vessels with wire gauge impellers were measured to be compared with those in vessels with disk turbine and paddle impellers. Also mass transfer volumetric coefficients for disk turbine, paddle impeller and wire gauge impeller in cylindrical agitated vessel was measured over a wide range of Reynolds number from turbulent flow to transition regions. The effect of geometries on $k_La$ is clarified experimentally. Mass transfer volumetric coefficients $k_La$ depends only on the power consumption ($P_{gv}+P_{av}$) per unit volume.

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Shape Finding of Cable-Net Structures by Using Modified Dynamic Relaxation Method (변형된 동적이완법을 이용한 케이블-네트 구조물의 형상해석)

  • 하창우;김재열;권택진
    • Proceedings of the Computational Structural Engineering Institute Conference
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    • 2000.10a
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    • pp.51-58
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    • 2000
  • Dynamic relaxation method is a shape finding analysis method for flexible structures by introducing the dynamic equilibrium equation. However, it is difficult for shape finding to estimate the most appropriate values for the mass and damping on each shape because the values are random one. In this study, the unit mass, the unit damping and the principal direction stiffness are utilized to avoid the random values, and the Newmarks assumption is introduced during the dynamic analysis. By introducing variant time increment method presented, the convergence time is reduced, that is, it can be reduced the total times for analysis.

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Engineering Qualification Model Design and Implementation of Mass Memory Unit for STSAT-3 (과학기술위성 3호 대용량 메모리 유닛의 인증모델 설계 및 구현)

  • Seo, In-Ho;Oh, Dae-Soo
    • Journal of the Korean Society for Aeronautical & Space Sciences
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    • v.37 no.12
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    • pp.1258-1263
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    • 2009
  • This paper describes the design and test results of engineering qualification model(EQM) of mass memory unit(MMU) for STSAT-3. The MMU for STSAT-3 having 32Gb mass memory capacity is capable of receiving and transmitting the mission data from MIRIS(Multi-purpose IR Imaging System) and COMIS(Compact Imaging Spectrometer) at 100Mbps and 10Mbps. The performance of EQM MMU was verified by the tests of data receiving from two payloads and data transmission to the data receiving system. Moreover, the vibration and thermal vacuum test was performed to verify the launch vehicle and space environments.

Productivity Analysis on the Standard Quantity-Per-Unit Costing Method and Work Crew Combination Method : Focused on Non-Vibration Mass Excavation Method (무진동굴착공법의 일위대가방식과 작업조방식의 생산성 비교 분석)

  • Lee, Dong Wook;Cho, Hong Jun;Lee, Keun Jo;Kim, Nam-Sik
    • KSCE Journal of Civil and Environmental Engineering Research
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    • v.31 no.3D
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    • pp.457-468
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    • 2011
  • Recently, the non-vibration mass excavation method is used on sewage pipes and road construction sites in Jeju. However, a construction cost estimation based on the unit quantity does not provide a proper unit price. In this study, a comparison of the productivity of the standard quantity-per-unit costing method and the one of the work crew combination method was made based on the site monitoring of the non-vibration mass excavation method that is used in construction sites near Jeju. For this, data of 35 sites were collected: a regression equation was derived from the 30 data, and verification was carried out through the remaining 5 data. The analysis concluded that a day's workload is $16.43m^3$. In addition, a combination of the equipment considering the site conditions and the amount of labor, which varies with the number of work crew was obtained in order to estimate the construction cost of the work crew combination method. The construction cost was calculated based on the one-day workload ($16.43m^3$) derived from the regression analysis. The cost then was analyzed and compared with the standard quantity-per-unit costing method.

Effect of Dietary Sodium Nitrate Consumption on Egg Production, Egg Quality Characteristics and Some Blood Indices in Native Hens of West Azarbaijan Province

  • Safary, H.;Daneshyar, Mohsen
    • Asian-Australasian Journal of Animal Sciences
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    • v.25 no.11
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    • pp.1611-1616
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    • 2012
  • The aim of the study was to evaluate the effect of sodium nitrate consumption on egg quality and quantity, and some blood parameters of native breeder hens of West Azerbaijan province. One hundred native hens were used from wk 25 to 32 of age. These birds were divided into two groups. One group was fed the control diet (CD) but the other fed the same diet supplemented with 4.2 g/kg sodium nitrate (ND). After 2 wks of adaptation, eggs were collected daily and egg mass and egg production were measured weekly for five weeks. To assess the egg quality parameters, two eggs from each replicate pen were collected for three consecutive days each week. At the end of experimental period (wk 32 of age), blood samples of 5 birds per replicate were collected from the wing vein into anticoagulant tubes. Dietary sodium nitrate didn't affect the egg production, shell stiffness, shell thickness and Haugh unit (p>0.05) but it decreased the both egg production and egg mass during the last three weeks (wks 30, 31 and 32) (p<0.05). Furthermore, a treatment effect was observed for yolk colour (p<0.05). Both the egg production and egg mass were increased over time (p<0.05). No significant treatment${\times}$time interaction was observed for egg weight, egg production and egg mass (p>0.05). No effect of time or treatment${\times}$time were observed for shell stiffness (p>0.05). Over time, shell thickness was decreased while Haugh unit increased (p<0.05). None of the blood TP and TG or the activity of ALT, AST and LDH enzymes were affected by dietary consumption of sodium nitrate at wk 32 of age (p>0.05). Sodium nitrite decreased both the TAC and TC at wk 32 of age (p<0.001). It was concluded that the lower body antioxidant capacity of nitrate fed birds resulted in the lower performance (egg weight, egg production and egg mass).

Factors Associated with the Lumbar Spine and Femoral Neck Bone Mineral Density in Korean Elderly Women (한국 여성 노인의 대퇴경부 및 요추 골밀도 관련 요인)

  • Kim, Young-Ran;Lee, Tae-Yong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.14 no.10
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    • pp.4943-4952
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    • 2013
  • This study was conducted among Korean women over aged 60 who participated in Korea National Health and Nutrition Examination Survey (KNHANES) (the 2nd and 3rd year at the 4th survey, and the 1st year at the 5th survey). The purpose of the study was to figure out a relation between femoral neck and lumbar spine bone mineral density and anthropometry, life style, diet, fracture history, family history of osteoporosis, medical history, menstrual history and reproductive factor. To express the strength of the associations, percent differences were calculated from multiple linear regression models using the formula ${\beta}{\times}$(unit/mean BMD). Unit for continuous variables were chosen to approximate 1 standard deviation(SD). In women aged 60 or older, lean mass(B: 0.257) and fat mass(B: 0.237) greatly influenced bone density in the femoral neck and lumbar spine. Therefore it will be an effective way to prevent osteoporosis for elderly women by increasing lean mass and maintaining proper weight.

Correlation between the Content and Pharmacokinetics of Ginsenosides from Four Different Preparation of Panax Ginseng C.A. Meyer in Rats

  • Jeon, Ji-Hyeon;Lee, Jaehyeok;Lee, Chul Haeng;Choi, Min-Koo;Song, Im-Sook
    • Mass Spectrometry Letters
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    • v.12 no.1
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    • pp.16-20
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    • 2021
  • We aimed to compare the content of ginsenosides and the pharmacokinetics after the oral administration of four different ginseng products at a dose of 1 g/kg in rats. The four different ginseng products were fresh ginseng extract, red ginseng extract, white ginseng extract, and saponin enriched white ginseng extract prepared from the radix of Panax ginseng C.A. Meyer. The ginsenoside concentrations in the ginseng product and the rat plasma samples were determined using a liquid chromatography-tandem mass spectrometry (LC-MS/MS). Eight or nine ginsenosides of the 15 tested ginsenosides were detected; however, the content and total ginsenosides varied depending on the preparation method. Moreover, the content of triglycosylated ginsenosides was higher than that of diglycosylated ginsenosides, and deglycosylated ginsenosides were not present in any preparation. After the single oral administrations of four different ginseng products in rats, only four ginsenosides, such as 20(S)-ginsenosides Rb1 (GRb1), GRb2, GRc, and GRd, were detected in the rat plasma samples among the 15 ginsenosides tested. The plasma concentrations of GRb1, GRb2, GRc, and GRd were different depends on the preparation method but pharmacokinetic features of the four ginseng products were similar. In conclusion, a good correlation between the area under the concentration curve and the content of GRb1, GRb2, and GRc, but not GRd, in the ginseng products was identified and it might be the result of their higher content and intestinal biotransformation of the ginseng product.