• Title/Summary/Keyword: $LN_2$

Search Result 892, Processing Time 0.031 seconds

Study on the Effect of Acupuncture at Jeonjung($CV_{17}$) on the Heart Rate Variability in Healthy Adults (단중혈(膻中穴) 침자극이 정상 성인의 심박변이도에 미치는 영향)

  • Park, Jin-Soo;Ahn, Min-Seob;Lee, Jeong-Ju;Choi, Byoung-Sun;Park, Min-Cheol;Yang, Hyun-Ju;Park, Ga-Young;Kim, Min-Chul;Jo, Eun-Heui
    • Journal of Acupuncture Research
    • /
    • v.28 no.2
    • /
    • pp.13-25
    • /
    • 2011
  • Objectives : This study was accomplished to investigate the effects of acupuncture at Jeonjung($CV_{17}$) on the heart rate variability(HRV) in healthy adults. And based on that, we tried to find out how acupuncture at Jeonjung($CV_{17}$) effects on the activity and balance of the autonomic nervous system. Methods : We investigated on 74 healthy volunteers consisted of 24 subjects in acupuncture group, 24 subjects in sham acupuncture group and 24 subjects in control group. On the other hand, two volunteers were ruled out by standard of elimination. The study was established by randomized trial. Acupuncture was applied at Jeonjung($CV_{17}$) during 10 minutes in acupuncture group and minimal acupuncture was applied at the same area in sham acupuncture group. No treatment was executed in control group. We measured HRV 3 times : baseline measurement and after treatment in acupuncture group and sham acupuncture group (after rest in control group) twise. The SPSS 15.0 for Windows was used to analyze the data by paired t-test, Wilcoxon signed ranks test (in group) and One-Way ANOVA, Kruskal-Wallis test (between the groups). Results: 1. In acupuncture group, Mean HRT, PSI, Normalized HF decreased significantly. SDNN, Ln (TP), Ln (LF), Ln (VLF), Normalized LF and LF/HF ratio increased significantly. RMSSD, Ln(HF) were not affected. 2. In sham acupuncture group, all indicators were not affected. 3. In control group, mean HRT, Ln(TP) decreased significantly. SDNN, RMSSD, PSI, Ln(LF), Ln(HF), Ln(VLF), normalized LF, normalized HF and LF/HF ratio were not affected. Conclusions : We suggest that acupuncture at Jeonjung($CV_{17}$) increases the activity of autonomic nervous system and makes effects on the balance of the autonomic nervous system.

Comparative Study on the Refrigeration Processes between Refrigeration Using Vapor Recompression and Refrigeration Using LN2 Cold Heat for the Carbon Dioxide Liquefaction (이산화탄소 액화를 위한 증기 재압축 냉동 공정과 액체질소 냉열을 이용한 냉동 공정의 비교 연구)

  • SANGGYUN NOH
    • Transactions of the Korean hydrogen and new energy society
    • /
    • v.34 no.5
    • /
    • pp.549-554
    • /
    • 2023
  • In this paper, three kinds of studies have been completed to obtain highly purified carbon dioxide having more than 7N purity as an electronic grade quality. PRO/II with PROVISION release January 2023 from AVEVA company was used, and Peng-Robinson equation of the state model with Twu's alpha function was selected for the modeling of the cryogenic distillation process. When using LN2 cold heat, we can obtain highest recovery of carbon dioxide as a bottom product for a cryogenic distillation column.

A Clinical Study on Relevance between Classified Dampness-Phlegm Pattern of Metabolic Syndrome and Heart Rate Variability (대사증후군의 습담 변증군과 심박변이도의 관련성에 관한 고찰)

  • Lee, Jae-Wook;Shin, Yoon-Ri;Bae, Su-Hyun;Park, Seon-Young;Choi, Sang-Ok;Kim, Kyoung-Min;Kim, Young-Kyun
    • The Journal of Internal Korean Medicine
    • /
    • v.33 no.3
    • /
    • pp.284-297
    • /
    • 2012
  • Objectives : This study was performed to investigate characteristic indice of heart rate variability (HRV) according to presence of metabolic syndrome (MS), pattern identification. Methods : We analyzed 167 subjects who participated in a stroke check-up. We classified the subjects into two groups as MS (n=48) and non-MS (n=119) based on NCEP ATP III. First, we investigated pattern identification of all subjects based on Korean Standard Pattern Identifications for Stroke-III. Second, we surveyed significance of HRV indices between MS and non-MS groups. Third, we investigated significance of HRV indices between classified DP of MS and classified DP of non-MS. Fourth, we investigated significance of HRV indices between classified DP of MS and non-MS. Fifth, we investigated significance between components of MS and HRV indices. Results : 1. SDNN, RMS-SD, HF, Ln(HF), and HF (NORM) were significantly lower in the MS than non-MS group. LN (TP), LF/HF were significantly higher in the MS than non-MS. 2. Ln (HF), Ln (TP), and LF/HF were statistically significant in the classified DP of MS group. 3. RMS-SD, and Ln (HF) were significantly lower in the abdominal obesity group than in the non-abdominal obesity group. SDNN, RMS-SD, TP, Ln (TP), VLF, Ln (VLF), and Ln (LF) were significantly lower in the hypertension group than in the non-hypertension group. RMS-SD was significantly lower in the diabetes group than in the non-diabetes group. Mean HRT,LF/HF were significantly higher in the hypertriglyceridemia than non-hypertriglyceridemia group, but Ln (HF), RMS-SD, and HF (NORM) were significantly lower in the hypertriglyceridemia than non-hypertriglyceridemia group. Conclusions : We found a few significant relationships between classified DP of MS and HRV indices. The resluts demonstrate that MS has potentially negative effects on the cardiovascular system, and these effects could be detected by HRV.

Spatial Distribution and Sampling Plan for Pink Citrus Rust Mite, Aculops pelekassi (Acari: Eriophyidae) in Citrus Orchard (감귤원에서 귤녹응애 공간분포 분석과 표본조사법 개발)

  • Song, Jeong-Heub;Hong, Soon-Yeong;Lee, Shin-Chan
    • Korean journal of applied entomology
    • /
    • v.51 no.2
    • /
    • pp.91-97
    • /
    • 2012
  • The dispersion indices, spatial pattern and sampling plan for pink citrus rust mite (PCRM), Aculops pelekassi, monitoring was investigated. Dispersion indices of PCRM indicated the aggregated spatial pattern. Taylor's power law provided better description of variance-mean relationship than Iwao's patchiness regression. Fixed-precision levels (D) of a sequential sampling plan were developed using by Taylor's power law parameters generated from PCRM on fruit sample (cumulated number of PCRM in $cm^2$ of fruit). Based on Kono-Sugino's empirical binomial the mean density per $cm^2$ could be estimated from fruit ratio with more than 12 rust mites per $cm^2$: $ln(m)=4.61+1.23ln[-ln(1-p_{12})]$. To determine the optimal tally threshold, the variance (var(lnm)) for mean (lnm) in Kono-Sugino equation was estimated. The lower and narrow ranged change of variance for esimated mean showed at a tally threshold of 12. To estimate PCRM mean density per $cm^2$ at fixed precision level 0.25, the required sample number was 13 trees, 5 fruits per tree and 2 points per fruit (total 130 samples).

Dosimetric Comparison of One Arc & Two Arc VMAT Plan for Prostate cancer patients (Prostate Cancer 환자에 대한 One Arc와 Two Arc VMAT Plan의 선량 측정 비교 분석)

  • Kim, Byoung Chan;Kim, Jong Deok;Kim, Hyo Jung;Park, Ho Chun;Baek, Jeong Ok
    • The Journal of Korean Society for Radiation Therapy
    • /
    • v.30 no.1_2
    • /
    • pp.107-116
    • /
    • 2018
  • Purpose : Intensity-modulated radiation therapy(IMRT) has been widely used for radiation therapy of Prostate Cancer because it can reduce radiation adverse effects on normal tissues and deliver more dose to the Prostate than 3D radiation therapy. Volumetric modulated arc therapy(VMAT) has been widely used due to recent advances in equipment and treatment techniques. VMAT can reduce treatment time by up to 55 % compared to IMRT, minimizing motion error during treatment. Materials and Methods : In this study, compared the MU and DVH values of 10 patients with prostate cancer by classifying them into 4 groups with 5 LN-Prostate groups and 5 Only-Prostate. And DQA measurements were performed using ArcCHECK and MapCHECK. Results : The results of Target and OAR dose distribution of Prostate patients are as follows. $D_{max}$ was in the range of 100~110 % in 4 groups, and more than 110 % of hot spot was not seen. Only-Prostate ($P_1$, $P_2$) without LN had a satisfactory dose distribution for the target dose, but slightly better for 2 arc plan($P_2$) than 1 arc plan($P_1$). The target dose $D_{98%}$ distribution in the LN-Prostate ($P_{L1}$, $P_{L2}$) group showed better 2 arc plan($P_{L2}$) than 1 arc plan($P_{L1}$), But in the case of 1 arc plan($P_{L1}$), the target dose $D_{98%}$ value was not enough. In OAR, the dose distribution of 1 Arc($P_1$) Plan and 2 Arc($P_2$) Plan in the Only-Prostate ($P_1$, $P_2$) Group satisfied the prescribed dose value. But, The dose distribution of 1 arc($P_1$) was slightly higher. In LN-Prostate OAR, 1 Arc($P_{L1}$) Plan showed higher dose than the prescribed dose. The Gamma evaluation pass rate of ArcCHECK and MapCHECK calculated from the DQA measurements was slightly higher than 99 % and the mean error range of the point dose measurements using the CC04 ion chamber was less than 1 %. Conclusion : In this study, Only-Prostate ($P_1$, $P_2$) group, the dose of 2 Arc plan was better. However, considering the treatment time and MU value, 1 Arc treatment method was more suitable. In the LN-Prostate ($P_{L1}$, $P_{L2}$) group, 2 Arc($P_{L2}$) treatment method showed better results and satisfied with Target $D_{98%}$ and OAR prescription dose.

  • PDF

초전도 케이블용 절연재료의 절연파괴 특성과 기구에 관한 연구 II

  • 김상현
    • Electrical & Electronic Materials
    • /
    • v.5 no.3
    • /
    • pp.303-309
    • /
    • 1992
  • 향후 급속히 증가할 것으로 예측되는 전력수요에 대비한 새로운 대전력 수송방법의 필요성이 최근 선진국들을 중심으로 강하게 대두되고 있다. 이러한 목적에서 초전도 케이블이 필요하나 신뢰성, 안정성, 결제성을 보장하기 위해서는 극저온절연 기술이 반드시 해결되어야 한다. 특히 고온 초전도체를 사용하는 초전도체 케이블의 냉각 및 절연재료로 사용될 액체 N$_{2}$(LN$_{2}$)의 절연파괴특성은 중요하다. 본 논문에서 LN$_{2}$의 절연파괴에 미치는 기포의 영향을 조사하고 정침에서는 정 Streamer, 부침에서는 기포파괴기구의 가능성을 검토하였다.

  • PDF

The Recognition Method for Focus Level using ECG(electrocardiogram) (심전도를 이용한 집중도 인식 방법)

  • Lee, Dong Won;Park, Sangin;Whang, Mincheol
    • The Journal of the Korea Contents Association
    • /
    • v.18 no.2
    • /
    • pp.370-377
    • /
    • 2018
  • Focus level has been important mental state in user study. Cardiac response has been related to focus and less clarified. The study was to determine cardiac parameters for recognizing focus level. The sixty participants were asked to play shooting game designed to control two focus levels. Electrocardiogram was measured during task. The parameters of time domain and frequency domain were determined from ECG. As a result of independent t-test, RRI, SDNN, rMSSD and pNN50 of time domain indicator were statistically significant in recognizing focus level. LF, HF, lnLF and lnHF of frequency domain were observed to be significant indicator. The rule base for recognition has been developed by the combination of RRI, rMSSD and lnHF. The rule base has been verified from another sixty data samples. The recognition accuracy were 95%. This study proposed significant cardiac indicators for recognizing focus level. The results provides objective measurement of focus in user interaction design in the fields of contents industry and service design.

Enhanced Piezoelectric Properties of Lead-Free La and Nb Co-Modified Bi0.5(Na0.84K0.16)0.5TiO3-SrTiO3 Ceramics

  • Malik, Rizwan Ahmed;Hussain, Ali;Maqbool, Adnan;Zaman, Arif;Song, Tae Kwon;Kim, Won Jeong;Kim, Myong Ho
    • Korean Journal of Materials Research
    • /
    • v.25 no.6
    • /
    • pp.288-292
    • /
    • 2015
  • New lead-free piezoelectric ceramics $0.96[\{Bi_{0.5}(Na_{0.84}K_{0.16})_{0.5}\}_{1-x}La_x(Ti_{1-y}Nb_y)O_3]-0.04SrTiO_3$ (BNKT-ST-LN, where $x=y=0.00{\leq}(x=y){\leq}0.015)$ were synthesized using the conventional solid-state reaction method. Their crystal structure, microstructure, and electrical properties were investigated as a function of the La and Nb (LN) content. The X-ray diffraction patterns revealed the formation of a single-phase perovskite structure for all the LN-modified BNKT-ST ceramics in this study. The temperature dependence of the dielectric curves showed that the maximum dielectric constant temperature ($T_m$) shifted towards lower temperatures and the curves became more diffuse with an increasing LN content. At the optimum composition (LN 0.005), a maximum value of remnant polarization ($33C/cm^2$) with a relatively low coercive field (22 kV/cm) and high piezoelectric constant (215 pC/N) was observed. These results indicate that the LN co-modified BNKT-ST ceramic system is a promising candidate for lead-free piezoelectric materials.

Application of Minimum Commitment Method for Predicting Long-Term Creep Life of Type 316LN Stainless Steel (Type 316LN 스테인리스강의 장시간 크리프 수명 예측을 위한 최소구속법의 적용)

  • Kim, Woo-Gon;Yin, Song-Nan;Ryu, Woo-Seog;Lee, Chan-Bock
    • Korean Journal of Metals and Materials
    • /
    • v.46 no.3
    • /
    • pp.118-124
    • /
    • 2008
  • Abstract: A minimum commitment method(MCM) was applied to predict the long-term creep rupture life for type 316LN stainless steel(SS). Lots of the creep-rupture data for the type 316LN SS were collected through world-wide literature surveys and the experimental data of KAERI. Using these data, the long-term creep rupture life above ${10}^5$ hour was predicted by means of the MCM. In order to obtain the most appropriate value for the constant A being used in the MCM equation, trial and error method was used for the wide ranges from -0.12 to 0.12, and the best value was determined by using the coefficient of determination, $R^2$ which is a statistical parameter. A suitable value for the A in type 316LN stainless steel was found to be at -0.02 ~ -0.05 ranges. It is considered that the MCM will be superior in creep-life prediction to commonly-used timetemperature parametric method, because the P(T) and G($\sigma$) functions are determined from the regression method based on experimental data.

Aqueous extract of Laurus nobilis leaf accelerates the alcohol metabolism and prevents liver damage in single-ethanol binge rats

  • Jae In Jung;Yean-Jung Choi;Jinhak Kim;Kwang-Soo Baek;Eun Ji Kim
    • Nutrition Research and Practice
    • /
    • v.17 no.6
    • /
    • pp.1113-1127
    • /
    • 2023
  • BACKGROUND/OBJECTIVES: Excessive alcohol consumption has harmful health effects, including alcohol hangovers and alcohol-related liver disease. Therefore, methods to accelerate the alcohol metabolism are needed. Laurus nobilis is a spice, flavoring agent, and traditional herbal medicine against various diseases. This study examined whether the standardized aqueous extract of L. nobilis leaves (LN) accelerates the alcohol metabolism and protects against liver damage in single-ethanol binge Sprague-Dawley (SD) rats. MATERIALS/METHODS: LN was administered orally to SD rats 1 h before ethanol administration (3 g/kg body weight [BW]) at 100 and 300 mg/kg BW. Blood samples were collected 0.5, 1, 2, and 4 h after ethanol administration. The livers were excised 1 h after ethanol administration to determine the hepatic enzyme activity. The alcohol dehydrogenase (ADH), aldehyde dehydrogenase (ALDH), superoxide dismutase (SOD), and glutathione peroxidase (GPx) activities in the liver tissue were measured. RESULTS: LN decreased the serum ethanol and acetaldehyde levels in ethanol-administered rats. LN increased the hepatic ADH and ALDH activities but decreased the alanine aminotransferase, aspartate aminotransferase, and gamma-glutamyl transferase activities in the ethanol-administered rats. In addition, LN inhibited lipid peroxidation and increased the activities of SOD and GPx. CONCLUSIONS: LN modulates the mediators of various etiological effects of excessive alcohol consumption and enhances the alcohol metabolism and antioxidant activity, making it a potential candidate for hangover treatments.