• Title/Summary/Keyword: Branching rate

Search Result 76, Processing Time 0.025 seconds

Modeling of Rheological Properties of Pectins by Side Branches (펙틴의 곁사슬에 의한 유변학적 성질에 대한 모델)

  • Shin, Hae-Hun;Hwang, Jae-Kwan
    • Korean Journal of Food Science and Technology
    • /
    • v.34 no.4
    • /
    • pp.583-589
    • /
    • 2002
  • The rheological properties of apple pectins and tomato pectins with different degrees of side branches (sample I and sample II) were investigated with wide range of shear rate by theological modeling. Among the Power law model, Cross model and Carreau model, the Carreau model was the best fitted to the experimental data. Increasing in branching of apple pectins resulted in higher zero-shear viscosity $({\eta}_0)$. But, tomato pectins that have a low degree of side branches were shown litte difference between sample I and sample II. It is concluded that side branches of pectins can result in significant difference in rheological properties. And, this is predicted by the Carreau model.

Comparison of Word Extraction Methods Based on Unsupervised Learning for Analyzing East Asian Traditional Medicine Texts (한의학 고문헌 텍스트 분석을 위한 비지도학습 기반 단어 추출 방법 비교)

  • Oh, Junho
    • Journal of Korean Medical classics
    • /
    • v.32 no.3
    • /
    • pp.47-57
    • /
    • 2019
  • Objectives : We aim to assist in choosing an appropriate method for word extraction when analyzing East Asian Traditional Medical texts based on unsupervised learning. Methods : In order to assign ranks to substrings, we conducted a test using one method(BE:Branching Entropy) for exterior boundary value, three methods(CS:cohesion score, TS:t-score, SL:simple-ll) for interior boundary value, and six methods(BExSL, BExTS, BExCS, CSxTS, CSxSL, TSxSL) from combining them. Results : When Miss Rate(MR) was used as the criterion, the error was minimal when the TS and SL were used together, while the error was maximum when CS was used alone. When number of segmented texts was applied as weight value, the results were the best in the case of SL, and the worst in the case of BE alone. Conclusions : Unsupervised-Learning-Based Word Extraction is a method that can be used to analyze texts without a prepared set of vocabulary data. When using this method, SL or the combination of SL and TS could be considered primarily.

Synthesis of High Molecular Weight Poly(vinyl alcohol) by Low Temperature Polymerization of Vinyl Acetate in Tertiary Butyl Alcohol and the Following Saponification (아세트산비닐의 삼차부틸알코올계 저온 중합 및 비누화에 의한 고분자량 폴리비닐알코올의 합성)

  • 류원석;한성수;최진현;유상우;홍성일
    • Polymer(Korea)
    • /
    • v.24 no.5
    • /
    • pp.610-620
    • /
    • 2000
  • Vinyl acetate (VAc) was polymerized at 30, 40, and 5$0^{\circ}C$ using 2,2'-azobis (2,4-dimethylvaleronitrile) (ADMVN) and tertiary butyl alcohol (TBA) as the initiator and the solvent, respectively. High molecular weight (HMW) atactic poly(vinyl alcohol) (PVA) was prepared by saponifying the poly(vinyl acetate) (PVAc) synthesized. The effect of polymerization conditions were investigated in terms of conversion, degree of branching for acetyl group of PVAc, and molecular weight of both PVAc and PVA. The polymerization rate of VAc in TBA was proportional to the 0.49th power of ADMVN concentration in good accordance with the theoretical value of 0.5. HMW-PVA with high yield could be obtained successfully, probably due to lower polymerization temperature and decreased chain transfer reaction rate which was achieved by adopting ADMVN and TBA. PYAc having average degree of polymerization (P$_{n}$) of 10000~13000 was obtained at the conversion of 35~70%. Saponification of so prepared PVAc yielded PVA having P$_{n}$ of 2400~6100. The syndiotactic diad content increased with decreasing polymerization temperature and increasing VAc concentration due to a steric hindrance effect of TBA during polymerization.

  • PDF

The Growth Analysis of Sowing Times in Safflower(Carthamus tinctorius L.) (파종시기별 홍화의 생장해석)

  • Kim, Jae-Cheol;Ryu, Jung-Gi;Kim, San-Young;Park, Kyeng-Seok
    • Korean Journal of Plant Resources
    • /
    • v.21 no.1
    • /
    • pp.47-51
    • /
    • 2008
  • This study was carried out to get the basic data for safflower cultivation according to sowing date by growth analysis for 2 years form 2003 to 2004 at Institute of natural product in Uiseong, G.B.A.R.E.S.. Safflower(Cheongsoo cultivar) was seeded at March 1st, April 1st, May 1st, and July 1st in field. The necessary date for germination was 24 days, when safflower was seeded at March 1st, but it was 8 days which sowed at April 1st and when the seed was sowed at high temperature period, the necessary date for germination was getting short. The necessary date for flowering was the same trend as germination; it took 104 days at March 1st, 79 days at April 1st, 65 days at May 1st, and 58 days at July 1st sowing treatment. The safflower growth was the most vigor when it was sowed at March 1st. T/R(Top/Root) ratio was gently increased during growing season, but when the seed was sowed at July 1 st, it was low compare to sowing at March 1st and April 1st. RGR(Relative growth rate) was the highest during shoot growth stage, but it was rapidly decreased after flowering. CGR(Crop growth rate) was increased at branching stage, and the increasing velocity was slightly decreased just before flowering, and it was increased again at flowering and at this stage, CGR was the highest, and then it did not increased. NAR(Net assimilation rate) was the highest at shoot growth stage during growing season, and was the highest which was sowed at March 1st.

Comparative Analysis of Lighting Intensity, Leaf Temperature, Transpiration Rate, and Vapor Pressure Deficit between the Top and Branching Point of Stem during Growing Period of Paprika Plant (파프리카 생장에 따른 줄기의 정부와 하부 간 광량, 엽온, 증산속도 및 수증기압포차 비교 분석)

  • Seung Mi Woo;Ho Cheol Kim
    • The Journal of the Convergence on Culture Technology
    • /
    • v.9 no.6
    • /
    • pp.1097-1101
    • /
    • 2023
  • As paprika plants grew in a glass greenhouse from November 2022 to March 2023, the amount of light at each plant height, leaf temperature, transpiration rate, and water vapor pressure were measured. Accumulated leaf temperature was higher at the top of the plant than at the bottom. Over time, the leaf temperature measured around 11-13 AM changed from 26.55→23.21→22.80→26.67℃ in the lower part (pL), and from 26.52→24.48→24.55→27.78℃ in the upper part (pAs). And VPD changed from 1.45→0.94→0.74→1.46kPa in pL and from 1.11→0.86→0.71→1.28kPa in pAs. Accordingly, the transpiration rate changed from 4.25→0.17→4.08→0.52mmol·m-2·s-1 in pL, 7.61→2.45→1.94→4.39→0.52mmol·m-2·s-1 in pAs, and from pAs to pL. It was significantly higher than The difference between the lower and upper parts (pL-pAs) was higher in pAs than pL in leaf temperature, light intensity, and transpiration rate, but the water vapor pressure difference was higher in pL. In this way, paprika shows differences in the environment and photosynthetic factors between the upper and lower parts during the cultivation period, so it is judged that this needs to be taken into consideration in future research.

Studies on Flowering and Maturity in Sesame(Sesamum indicum L.) VI. Grain Filling Rate for Differently Positioned Capsules in Different Plant Types (참깨 개화, 등숙에 관한 연구 VI. 참깨 초형에 따른 착삭부위별 등숙율)

  • Jung-Il Lee;;Eung-Ryong Son
    • KOREAN JOURNAL OF CROP SCIENCE
    • /
    • v.31 no.2
    • /
    • pp.214-219
    • /
    • 1986
  • This study was conducted to provide basic information to breeders and agronomists working with sesame. Grain filling rate were investigated for eight plant types classified by branching habit, capsules per axil, carpels and loculi of a capsule. Two typical cultivars were chosen for plant type among 527 gene pools. Grain filling rate didn't increase with little difference between lower and middle part capsules, Jut significantly decreased in upper part. Grain filling rate of lower part, main stem and center capsules appeared higher than that of upper part, branch and side capsule for grain filling. Mono-capsule setting and unbranched plant type were higher for grain filling than tricapsule setting and branched type due to inactive ripenness on branched capsule. NMB type showed that best maturity and relatively good grain filling in BTB type despite it's largest sink capacity. NTQ and BTQ type appeared poor ripenness because of immaturity of higher part side capsules; however it was believed that there were still possibilities for improving ripenness in 3 capsule and 4 carpels 8 loculi type by the good maturity of 1 capsule and 4 carpels 8 loculi type.

  • PDF

Dose rate conversion factor for soil by the beta-rays and gamma-rays from 238,235U, 232Th and 40K (238,235U, 232Th과 40K의 베타선 및 감마선에 의한 토양의 흡수선량 환산 인자)

  • Kim, Gi-Dong;Eum, Chul-Hun;Bang, Jun-Hwan
    • Analytical Science and Technology
    • /
    • v.20 no.6
    • /
    • pp.460-467
    • /
    • 2007
  • Dose rate conversion factor was calculated to estimate the absorbed effective annual doses for soils for the beta-rays and gamma-rays, which were emitted from $^{238,235}U$, $^{232}Th$, and $^{40}K$ isotopes. The most recent data of the emitted energies per decay, half-lifes, and branching ratios, which were obtained from National Nuclear Data Center, were used. When this factor and the effective annual doses for the beta-rays and the gamma-rays of natural radioisotopes were compared with those of Aitken, these of $^{238}U$, $^{232}Th$ and $^{40}K$ are estimated to have good agreements but a large difference is shown in this for $^{235}U$. Through the calculations of effective annual doses by using these factor and the measurements of gamma-ray spectra for soils, which were extracted from prehistoric remains (Mansuri) on Osong, Chungchengbuk-do, The annual effective doses were obtained to be 3.8~5.9 mGy/yr. Also, when these doses including decay elements upper Rn were compared with those on all isotopes, the differences within 9~30 % were obtained. The analysis method of the annual effective doses for the beta-rays and the gamma-rays of the natural isotopes of soils was established by this dose rate conversion factor.

AN EXPERIMENTAL STUDY ON THE FATIGUE FRACTURE OF LAMINATE PORCELAIN (치과용 라미네이트 도재의 피로파괴에 관한 실험적 연구)

  • Park Charn-Woon;Bae Tae-Sung;Lee Sang-Don
    • The Journal of Korean Academy of Prosthodontics
    • /
    • v.31 no.4
    • /
    • pp.482-505
    • /
    • 1993
  • The purpose of this study was to evaluate the fracture characteristics and the effect of resin bonding of laminate porcelain. In order to characterize the indentation-induced crack, Young's moduli and characteristic indentation dimensions were measured. The fatigue life under three point flexure test was measured using the electro-dynamic type fatigue machine, and the crack propagation with thermocycling was investigated on the condition of 15 second dwell time each in $5^{\circ}C\;and\;55^{\circ}C$ bath. The Vickers indentation pattern and the fracture surface were examined by an optical microscope and a scanning electron microscope (SEM). The results obtained were summarized as follows ; 1. Young's moduli(E) of the laminate porcelain and the resin cement used in this experiment were $62.56{\pm}3.79GPa$ and $15.01{\pm}0.12GPa$, respectively. 2. The initial crack size of the laminate porcelain was $69.19{\pm}5.94{\mu}m$ when an indentation load of 9.8N was applied, and the fracture toughness was $1.065{\pm}0.156MPa\;m^{1/2}$. 3. The fatigue life of laminate porcelain showed the constant fracture range at the stress level 27.46-35.30MPa. 4. When a cyclic flexure load was applied, the fatigue life of resin-bonded laminate porcelain was more decreased than that of laminate porcelain. 5. When a thermocycling was conducted, the crack growth rate of resin-bonded laminate porcelain was more increased than that of laminate porcelain. 6. Fracture surface showed the radial crack, the lateral crack, and the macroscopic crack branching region beneath the plastic deformation region when an indentation load of 9.8N was applied.

  • PDF

Hemodynamic Interpretation of Various Extraanatomical Bypasses: Clinical & Engineering Views

  • Lee, Byung-Boong;Kim, Young-Wook;Suh, Sang-Ho;Roh, Hyung-Woon;Kim, Dong-Ik;Yoo, Sang-Sin;Cho, Min-Tae;Huh, Sung
    • International Journal of Vascular Biomedical Engineering
    • /
    • v.1 no.1
    • /
    • pp.32-40
    • /
    • 2003
  • Axillo-bifemoral (Ax-Fem) bypass are now well accepted for bilateral iliac artery occlusion as the second best option. This extra-anatomical (unnatural) bypasses, however, have various hemodynamic liabilities affecting the patency. Hemodynamic conditions of each different type of Ax-Fem bypass were assessed with computer simulation model to determine the hemodynamically more sound type. Simulation models of five different types of Ax-Fem bypass were constructed. Our investigation based on the computer simulation models have shown distinct differences between two most popular Lazy-S type and Inverted-C type on the distribution of flow volume, shear stress and recirculation zone, etc., though both types have shown similar clinical results. Lazy-S type has shown better hemodyanmic status than inverted-C type. The theoretical advantage of "Lazy-S" type has never been adequately proved for its superiority clinically over the inverted-C type. Inverted-C type is now in more favor with clinically better results in spite of many hemodynamic liabilities including retrograde flow to the branching graft. The improvement of over-all long-term patency rate of various extra-anatomical bypasses is still warranted through proper correction of the hemodynamic liability. Even though clinical outcome of the extra-anatomical bypass has been equal regardless of the type of crossover femoral graft configuration, there are distinct differences on the hemodynamic characteristics among various types of configuration. Further hemodynamic study in the pulsatile flow status is warranted to correct hemodynamic defects with proper modification of various hemodynamic factors of each model.

  • PDF

Analytical Study on the Discharge Transients of a Steam Discharging Pipe (증기방출배관의 급격과도현상에 대한 해석적 연구)

  • 조봉현;김환열;강형석;배윤영;이계복
    • Journal of Energy Engineering
    • /
    • v.7 no.2
    • /
    • pp.202-208
    • /
    • 1998
  • As in the other industrial processes, a nuclear power plant involves a steam relieving process through which condensable steam is discharged and condensed in a subcooled pool. An analysis of steam discharge transients was carried out using the method of characteristics to determine the flow characteristics and dynamic loads of piping that are used for structural design of the piping and its supports. The analysis included not only the steam flow rate but also the flow rates of the air and water which originally exist in the pipe. The analytical model was developed for a uniform pipe with friction through which the flow was discharged into a suppression pool. Including the combinations of system elements such as reservoir, valve and branching pipe lines. The piping flow characteristics and dynamic loads were calculated by varying system pressure, pipe length, and submergence depth. It was found that the dynamic load, water clearing time and water clearing velocity at the water/air interface were dependent not only on the system pressure and temperature but also on the pipe length and submergence depth.

  • PDF