• Title/Summary/Keyword: 14 S-N Method

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Equivalence Ratio Measurements in Gas Spray Using Laser Raman Scattering (Laser Raman Scattering을 이용한 가스 분무내 당량비 계측에 관한 연구)

  • Jin, S.H.;Park, K.S.;Song, J.I.;Kim, G.S.
    • Journal of ILASS-Korea
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    • v.2 no.4
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    • pp.7-14
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    • 1997
  • Laser Raman scattering method has been applied to measure equivalence ratio of methane/air mixture in injected spray. We used high power KrF excimer laser$(\lambda=248nm)$ and a high gain ICCD camera to capture low intensity signal. Raman shifts and Raman scattering cross -sections of $H_2,\;O_2,\;N_2,\;CO_2,\;CH_4\;and\;C_3H_8$ are measured precisely. Our results show an excellent agreement with those of other groups. Mole fraction measurement of $O_2\;and\;N_2$ from air shows that $O_2:N_2=0.206:0.794$. We used gas injector which was operated at 1 bar. Methane is used as a fuel. Spray region is $10mm\times37mm$ and this region is divided into 80 points. In Raman signals are obtained and ensemble averaged for each point. 3-d and contour plot of distribution of equuivalence ratio is presented. Our measured results show that the equivalence ratio of methane/air mixture in methane-rich region is reasonable. However, more study is necessary for methane-lean region because background noise level is almost same as Raman intensity of methane.

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Laplace's Method for General Integrals with Applications to Statistical Mechanics

  • Park, Nae-Hyun;Jeon, Jong-Woo
    • Journal of the Korean Statistical Society
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    • v.14 no.2
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    • pp.87-94
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    • 1985
  • This paper extends the results of Ellis and Rosen (1982 a) to some more general integrals and applies our main theorem to compute the specific free energy of some models in statistical mechanics. The general integrals of this paper mean the integrals with respect to the probability measures induced by the sample mean of n i.i.d. random variables taking values in a separable Banach space.

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Studies on the Composition of Species and Distribution of Evergreen Forest in Haenam Peninsula , Korea (海南半島의 常綠樹林의 種組成과 分布에 關한 硏究)

  • Kim, Chul-Soo;Oh, Jang-Geun
    • The Korean Journal of Ecology
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    • v.14 no.3
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    • pp.243-255
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    • 1991
  • The vegetation of haenam peninsula(126 30e.l. and 34 30n.l ) was investigated from July, 1990 to 1991. the units of vegetatin were classified by the phytosociological method of broun- blanquet's. the forest vegetation was classified into 7 communities, sasa borealis-quercus acuta, cinnamomum japonicum, camellia japonica, rhododendron mucronulatum-pinus thunbergii, pinus densiflora community, torreya nucifera, chamaecyparis obtusa afforestatio, and the actual vegetation map was drawn in 1 : 50,00 scaie.

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The Magnetic Properties of Co-Ni-Fe-N Soft Magnetic Thin Films

  • Kim, Y. M.;Park, D.;Kim, K. H.;Kim, J.;S. H. Han;Kim, H. J.
    • Journal of Magnetics
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    • v.5 no.4
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    • pp.120-123
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    • 2000
  • Co-Ni-Fe-N thin films were fabricated by a $N_2$ reactive rf magnetron sputtering method. The nitrogen partial pressure ($P_{N2}$) was varied in the range 0~10% . As$P_{N2}$ increases in this range, the saturation magnetization $B_s$ linearly decreases from 19.8 kG to 14 kG and the electrical resistivity ($\rho$) increases from 27 to 155 $\mu\Omegacm$. The coercivity $H_c$ exhibits the minimum value at 4% $P_{N2}$. The magnetic anisotropy fields ($H_k$) are in the range of 20$\sim$50 Oe. High frequency characteristics of $(Co_{22.2}Ni_{27.6}Fe_{50.2})_{100-x}N_x$ films are excellent in the range of 3$\sim$5% of $P_{N2}$. In particular, the effective permeability of the film fabricated at 4% $P_{N2}$ is 800, which is maintained up to 600 MHz. This film also shows Bs of 17.5 kG, $H_c$/ of 1.4 Oe, resistivity of 98$\mu\Omegacm$ and $H_k$ of about 25 Oe. Also, the corrosion resistance of $(Co_{22.2}Ni_{27.6}Fe_{50.2})_{100-x}N_x$ films was imp roved with increasing N concentration.

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THE MAGNETIC PROPERTIES OF Co-Ni-Fe-N SOFT MAGNETIC THIN FILMS

  • Kim, Y. M.;Park, D.;Kim, K. H.;Kim, J.;S. H. Han;Kim, H. J.
    • Proceedings of the Korean Magnestics Society Conference
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    • 2000.09a
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    • pp.492-499
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    • 2000
  • Co-Ni-Fe-N thin films were fabricated by a N$\sub$2/ reactive rf magnetron sputtering method. The nitrogen partial pressure (P$\sub$N2/) was varied in the range of 0∼10%. As P$\sub$N2/ increases in this range, the saturation magnetization (B$\sub$s/) linearly decreases from 19.8 kG to 14 kG and the electrical resistivity ($\rho$) increased from 27 to 155 ${\mu}$$\Omega$cm. The coercivity (H$\sub$c/) exhibits the minimum value at 4% of P$\sub$N2/. The magnetic anisotropy (H$\sub$k/) are in the range of 20∼50 Oe. High frequency characteristics of (Co$\sub$22.2/Ni$\sub$27.6/Fe$\sub$50.2/)$\sub$100-x/N$\sub$x/ films are excellent in the range of 3∼5% of P$\sub$N2/. Especially the effective permeability of the film fabricated at 4% of P$\sub$N2/ is 800, which is maintained up to 600 MHz. This film also shows Bs of 17.5 kG, H$\sub$c/ of 1.4 Oe, resistivity of 98 $\Omega$cm and H$\sub$k/ of about 25 Oe. Also, the corrosion resistance of (Co$\sub$22.2/Ni$\sub$27.6/Fe$\sub$50.2/)$\sub$100-x/N$\sub$x/ were improved with the increase in N concentration.

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The electrochemical properties of PVD-grown WC-( $Ti_{1-x}$A $I_{x}$)N multiplayer films in a 3.5% NaCl solution

  • Ahn, S.H.;Yoo, J.H.;Kim, J.G.;Lee, H.Y.;Han, J.G.
    • Journal of Surface Science and Engineering
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    • v.34 no.5
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    • pp.435-444
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    • 2001
  • WC-( $Ti_{1-x}$ A $l_{x}$) N coatings of constant changing Al concentration were deposited on S45C substrates by high-ionization sputtered PVD method. The Al concentration could be controlled by using evaporation source for Al and fixing the evaporation rate of the metals (i.e, WC- $Ti_{0.86}$A $l_{0.14}$N, WC- $Ti_{0.72}$A $l_{0.28}$N, and WC- $Ti_{0.58}$A $l_{0.42}$N). The corrosion behavior of WC-( $Ti_{1-x}$ A $l_{x}$)N coatings in a deaerated 3.5% NaCl solution was investigated by electrochemical corrosion tests and surface analyses. The measured galvanic corrosion currents between coating and substrate indicated that WC- $Ti_{0.72}$A $l_{0.28}$N coating showed the best resistance of the coating tested. The results of potentiodynamic polarization tests showed that the WC- $Ti_{0.72}$A $l_{0.28}$N coating deposited with 32W/c $m^2$ of Al target revealed higher corrosion resistance. This indicated that the WC- $Ti_{0.72}$A $l_{0.28}$N coating is effective in improving corrosion resistance. In EIS, the WC- $Ti_{0.72}$A $l_{0.28}$N coating showed one time constant loop and increased a polarization resistance of coating ( $R_{coat}$) relative to other samples. Compositional variations of WC-( $Ti_{1-x}$ A $l_{x}$)N coatings were analyzed by EDS and XRD analysis was performed to evaluate the crystal structure and compounds formation behavior. Surface morphologies of the films were observed using SEM and AFM. Scratch test was performed to measure film adhesion strength.strength. adhesion strength.strength.

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Mantle Cell Lymphoma: A North Indian Tertiary Care Centre Experience

  • Das, Chandan Krushna;Gogia, Ajay;Kumar, Lalit;Sharma, Atul;Sharma, Mehar Chand;Mallick, Saumya Ranjan
    • Asian Pacific Journal of Cancer Prevention
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    • v.17 no.10
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    • pp.4583-4586
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    • 2016
  • Background: Mantle cell lymphoma (MCL) is an aggressive non-Hodgkin's lymphoma, with a pathognomonic chromosomal translocation t (11;14). Prognosis is uniformly dismal but there is a paucity of information on MCL from India. Materials and methods: We retrospectively analysed clinicopathological information on all treated patients with MCL at our centre. STATA 14.0 was used for analysis. Survival was assessed by Kaplan-Meier analysis and the Cox's proportional hazards method. Statistical significance was defined as a P value of < 0.05. Results: Fifty-one patients with MCL were reviewed. The median age at presentation was 57.0 years. Extranodal involvement was seen in 39.0 (74.0%) while bone marrow positivity at presentation was found in 27.0 (54.0%). Initial treatment was chemotherapy with or without rituximab. Patients receiving rituximab-based therapy (n = 24) had 5-year progression-free survival (PFS) of 21.0 (88.0%), compared with 14.0 (61.0%) for those not receiving rituximab (n = 23, P = 0.036). Twenty-three patients were alive with a median follow-up of 20.7 months (range 2.5-89.2). PFS at 1 and 2 years was 51.0% and 27.0%, and overall survival (OS) 78.0% and 72.0%, respectively. Use of more than 2.0 lines of therapy, use of bendamustine-rituximab, and high TLC (>10,000.0/cu.mm) significantly affected PFS. Conclusions: In our experience, MCL patients from north India have an early age at presentation. When treated with regimens including rituximab results in an improved response rate and PFS. This study provided comprehensive insights into the treatment of MCL in a developing country.

Rabbit's Cervical Tracheal Replacement with Cryopreserved Homograft - Effects on the Viability and Rejection - (토끼 경부기관의 초냉동보관 동종이식편 기관 이식술 - 생육성 및 거부반응에 미치는 영향 -)

  • 원태희;서정욱;성숙환
    • Journal of Chest Surgery
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    • v.31 no.12
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    • pp.1127-1133
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    • 1998
  • Background: There are no ideal substitutes for tracheal replacement. Therefore we investigated the possibility of clinical use of cryopreserved tracheal homograft with special interest in the viability and rejection of the epithelial cell and cartilage. Material and Method: Rabbit's trachea was sected and stored in liquid nitrogen tank for 1 month. Tracheal replacement was done in 45 rabbits with autograft(n=15, Group 1), fresh allograft(n=15, Group 2) and cryopreserved homograft(n=15, Group 3). After 7, 14, and 30 days, 5 rabbits in each group were sacrificed and the regeneration of epithelium and cartilage and the degree of rejection were assessed by counting the monocellular infiltration. Result: Investigation at day 7, showed no difference in epithelial regeneration, however, at days 14 and 30, Group 1 showed better regeneration of epithelium than groups 2 and 3. There was no difference of epithelial regeneration between group 2 and 3. There was little rejection at day 7, but at days 14 and 30, there was significant rejection in group 2 and group 3.(P<0.05). Group 3 showed lesser rejection than group 2 at days 14 and 30, but it was not statistically significant. Cartilage showed no rejection and maintained its viability in groups 2 and 3. Conclusion: Cryopreserved tracheal homograft can maintain its viability, therefore it may represent a possibility of clinical application for tracheal replacement. However, cryopreservation can not eliminate the antigenicity of the trachea completely. Furthere studies for lowering the antigenicity and rejection should be performed for an ideal substitute for tracheal replacement.

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Ultrarapid Freezing of Mouse Ova (생쥐난자의 초급속동결)

  • 박영식;서태광;이택후;전상식
    • Journal of Embryo Transfer
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    • v.10 no.3
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    • pp.203-208
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    • 1995
  • This study was carried out to efficiently use the ultrarapid freezing method in the cryopreservation of mouse ova. For this, the effects of dehydration method, oval vigour and $0^{\circ}C$ controlling method on post-thawing viability were investigated. Fresh mouse ova were dehydrated in mPBS with 3.5M DMSO and /or 0.25M sucrose, and directly immersed in L$N_2$ for ultrarapidly freezing. The frozen ova were thawed at 37$^{\circ}C$, rehydrated in mPBS with 0.25M sucrose, and then repeatedly washed in HAM's Fl0 before evaluating the morphological normality of frozen-thawed ova. The results obtained showed that there was difference between treatments in a experiment. 1) The post-thawing viability of ova dehydrated in multi-step (48.4$\pm$13.8%) was higher than that of ova in two-step (40.9$\pm$14.0%). 2) The post-thawing viability of fertilized ova (87$\pm$14.0%) was significantly(p<0.0l) higher than that of unfertilized ova (5.4$\pm$5.4%). 3) The post-thawing viability of ova dehydrated and rehydrated using a cooling machine (95.8$\pm$4.2%) was significantly(p<0.05) higher than that on ice(84.1$\pm$9.9). In conclusion, in order to efficiently cryopreserve ova in vitro with ultrarapidly freezing method, highly viable embryos should be selected, heavy osmotic shock to the dehydrating ova should be avoided, and embryos in high osmotic condition were dehydrated and rehydrated in a constantly low temperature.

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Fatigue Life Estimation Using the Multi-Axial Multi-Point Load Counting Method under Variable Amplitude Loading (가변진폭하중하에서 다축-다점 하중 Counting method를 이용한 피로수명평가)

  • Lee, W.S.;Lee, H.W.
    • Journal of the Korean Society for Precision Engineering
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    • v.14 no.6
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    • pp.22-27
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    • 1997
  • In general, the load which acts on the structure is almost independent of time in many locations. In this case. It is difficult to estimate the life with the service load history, because the structure is on the multi- axial and multi-point loading states. In this study, the service load of the excavator which is widely used in industry field was calculated using measured cylinder pressures and displacements. The fatigue life was estimated using the multi-axial and multi-point load counting method. Service load history of 4 pin joint which act independently each other is yielded by mult-axial and multi-point load counting method. The stress spectrum is yielded by superposition of the results of FEM stress analysis applied unit load. Palm- gren-Miner's cumulative Damage is 0.000804 for Von Mises equivalent stress sequence by one side fillet weld S-N curve. This result agress with Bench test results. As a result of this study, the fatigue life esti- mation using the multi-axial and multi-axial and multi-point load counting method is useful.

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