• 상하수도학회지
• /
• 제26권6호
• /
• pp.767-777
• /
• 2012

Annular Biofilm Reactor (ABR) equipped with coupons of three different pipe materials (STS 304, PVC, PE) was used to generate drinking water biofilm samples. The level of assimilable organic carbon (AOC) during the sample generation period was $37.3{\mu}g/L$, and this level did not seem to be low enough to limit the formation of biofilm in this study. Terminal-restriction fragment length polymorphism (T-RFLP) analyses determined T-RF profile as early as 3 h of exposure on PVC coupons. Average surface roughness ($R_a$) measured by atomic force microscopic analyses was 125.7 nm for PVC, and this value was higher than for STS (71.6 nm) and PE (74.0 nm). However, biofilm formation was faster on STS (6 h) than on PE (12 h), which indicated that surface roughness might not be the only factor that controlled the initiation of biofilm development. Upon detection of the T-RF peaks, richness (S) and diversity indices such as Shannon (H) and Simpson (1/D) demonstrated a rather slow increase until 48 h followed by rapid increase regardless of the pipe materials. Differences of microbial community structures among the biofilm samples were determined based on the cluster analysis using Jaccard coefficients (Sj). Biofilm communities could be divided into two distinct groups according to the exposure time regardless of the pipe materials. First group contained a young (< 48 h) biofilm samples (10 out of 11) but second group contained a mature (${\geq}$ 48 h) samples (11 out of 14). Results suggested that, due to the complexity of biofilm, the targeting of the first group of cluster was crucial for optimizing the management of drinking water distribution systems and controlling microbial growth.

• 한국정보처리학회논문지
• /
• 제7권9호
• /
• pp.2940-2947
• /
• 2000

무선 ATM 환경에서 다양한 멀티미디어 트래픽을 지원하기 위해서는 매체 접RMS 제어(MAC) 프로토콜이 필요하다. MAC 프로토콜은 다양한 트래픽 클래스에 대한 QoS를 보장하면서 제한된 무선 대역폭을 효율적으로 활용할 수 있도록 설계되어야 한다. 본 논문에서는 서로 다른 종류의 트래픽이 혼재된 무선 ATM 환경에서 각 서비스 클래스의 QoS를 만족할 수 있는 동적 자원 할당 방식 기반의 MAC 프로토콜을 제안하였다. CBR이나 VBR에 비해 낮은 우선 순위를 가지는 ABR 트래픽에 대해서는 최소 대역폭을 확보함으로써 지연을 크게 개선하였으며, 실시간 VBR 트래픽의 경우에는 대역폭이 초기에 경쟁을 통해 할당되고 이후로는 경쟁 없이 대역폭을 할달함으로써 처리율을 증가시켰다.

• 한국식품영양과학회지
• /
• 제28권3호
• /
• pp.710-721
• /
• 1999

This study was conducted to investigate the hematological characteristics and risk factors of hypercholesterolemia(HC) in Korean. 344 adult men who took the annual health check ups at D or J hospitals were participated in this cross sectional study. The subjects were grouped by plasma total cholesterol level into three groups: normal cholesterolemic(n=139), borderline hypercholesterolemic (n=93) and hypercholesterolemic(n=112) groups. The data of systolic and diastolic blood pressure (SBP/DBP), hemoglobin, plasma glucose, albumin and cholesterol levels were collected from medical records. The levels of plasma triglyceride(TG), HDL C, phospholipid, insulin, apo A and apo B were measured. The levels of plasma LDL C, VLDL C and atherogenic index(AI) were calculated. The subjects with HC had significantly higher SBP and DBP, albumin, TG, phospholipid, HDL C, LDL C, VLDL C and apo B level than those of the normal subjects. The relative and attributable risks on HC were 1.59 and 0.18 for hypertension(SBP/DBP$\geq$160/95), 2.08 and 0.35 for hypertriglyceridemia (TG $\geq$400mg/dl). Plasma total cholesterol level was positively correlated with several hematologic parameters: age(r=0.1242, p<0.05), DBP(r=0.1194, p<0.05), albumin(r=0.2029, p<0.001), plasma TG(r= 0.3829, p<0.001), phospholipid(r=0.6036, p<0.001), LDL C(r=0.8572, p<0.001), HDL C(r=0.2399, p< 0.001), AI(r=0.3116, p<0.001), apo B(r=0.2602, p<0.05) and Lp(a)(r=0.1372, p<0.05). However, plasma total cholesterol level was negatively correlated with the levels of Apo A1(r= 0.2922, p<0.001), and ABR(r= 0.3598, p<0.001).

• 한국물환경학회지
• /
• 제21권3호
• /
• pp.256-262
• /
• 2005

The purpose of this study is to investigate the performances of organic removal and methane recovery by using a full scale two-phase anaerobic system. The full scale two-phase anaerobic process was consists of an acidogenic anaerobic baffled reactor (ABR) and a methanognic upflow anaerobic sludge blanket (UASB) reactor. The volumes of acidogenic and methanogenic reactors were designed to $28.3m^3$ and $75.3m^3$. The two-phase anaerobic system represented 60-82% of COD removal efficiency when the influent COD concentration was in the range of 7,150 to 16,270 mg/L after screening (average concentration is 10,280 mg/L). After steady-state, the effluent COD concentration in the methanogenic reactor showed $2,740{\pm}330 mg/L$ by representing average COD removal efficiency was $71.4{\pm}8.1%$ when the operating temperature was in the range of $19-32^{\circ}C$. The effluent SCOD concentration was in the range of 2,000-3,000 mg/L at the steady state while the volatile fatty acid concentration was not detected in the effluent. Meanwhile, the COD removal efficiency in the acidogenic reactor showed less than 5%. The acidogenic reactor played key roles to reduce a shock-loading when periodic shock loading was applied and to acidify influent organics. Due to the high concentration of alkalinity and high pH in the effluent of the methanogenic reactor, over 80% of methane in the biogas was produced consistently. More than 70% of methane was recovered from theoretical methane production of TCOD removed in this research. The produced gas can be directly used as a heat source to increase the reactor temperature.

• 한국수소및신에너지학회논문집
• /
• 제35권3호
• /
• pp.336-344
• /
• 2024

In this study, a Ni_0.9Co_0.05Mn_0.05(OH)₂ precursor used as an anode active material using a black powder leaching solution of a recycled lithium ion battery was prepared through coprecipitation synthesis with co-precipitation time, NH₄OH concentration, pH, and stirring time as variables. The characteristics of the prepared powder were analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM), particle size analysis (PSA), and inductively coupled plasma optical emission spectroscopy (ICP-OES). It was confirmed that the single crystal thickness of the LiNi_1-x-yCo_xMn_yO₂ (NCM) precursor changes depending on the NH₄OH concentration and reaction pH value, and thicker single crystals are formed at 2 M NH₄OH compared to 1 M and at pH 10.8-11.8 compared to pH 11.8-12.0. NCM precursor particles increased with coprecipitation time, and it was confirmed that the 72 hours NCM precursor had the largest particle size. Through ICP-OES analysis, it was confirmed that the NCM precursor was synthesized with the target composition of Ni²⁺:Co²⁺:Mn²⁺=90:5:5.

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
• /
• pp.210-213
• /
• 2008

The purpose of this study is to investigate the performances of organic removal and methane recovery in the full scale two-phase anaerobic system. The full scale two-phase anaerobic system was consists of an acidogenic ABR (Anaerobic Baffled Reactor) and a methanognic UASB (Upflow Anaerobic Sludge Blanket) reactor. The volume of acidogenic and methanogenic reactors is designed to 28.3 $m^3$ and 75.3 $m^3$. The two-phase anaerobic system represented 60-82% of COD removal efficiency when the influent COD concentration was in the range of 7,150 to 16,270 mg/L after screening (average concentration is 10,280 mg/L). After steady-state, the effluent COD concentration in the methanogenic reactor showed 2,740 $\pm$ 330 mg/L by representing average COD removal efficiency was 71.4 $\pm$ 8.1% when the operating temperature was in the range of 19-32$^{\circ}C$. The effluent SCOD concentration was in the range of 2,000-3,000 mg/L at the steady state while the volatile fatty concentration was not detected in the effluent. Meanwhile, the COD removal efficiency in the acidogenic reactor showed less than 5%. The acidogenic reactor played key roles to reduce a shock-loading when periodic shock loading was applied and to acidify influent organics. Due to the high concentration of alkalinity and high pH in the effluent of the methanogenic reactor, over 80% of methane in the biogas was produced consistently. More than 70 % of methane was recovered from theoretical methane production of TCOD removed in this research. The produced gas can be directly used as a heat source to increase the reactor temperature.

• 사상체질의학회지
• /
• 제19권2호
• /
• pp.82-93
• /
• 2007

1. Objectives Functional medicine is a system which utilizes certain Investigative and treatment methods that are primarily oriented toward the recognition of functional disorder. The 7-zone-diagnostic system(VEGA-DFM722 and ABR-2000, etc) is a diagnostic device which applies pulse signals to predetermined bodily locations. We think that we can discriminate between Soeumin, Soyangin and Taeumin with this system. 2. Methods The subject of our study is no disease men and women who are decided the same constitution both survey of the QSCC II and diagnosis of specialist of the Sasang Constitution. All subject are 76(Soeumin(N=24), Soyangin(N=17), Taeumin(N=35)) cases. We make an analysis of a distinctive feature on the result of the VEGA-DFM722. 3. Results and Conclusions 1) Soeumin or Taeumin women had that the red bar graphs of and 1, 2 and 3 are lower than the red bar graphs of zone 4, 5, 6 and 7 in factor AA on the result of the VEGA-DFM722 with the naked eye. Soyangin or Taeumin men had that the red bar graphs of zone 1,2 and 3 are higher than the red bar graphs of tone 4, 5, 6 and 7 in factor AA on the result of the VEGA-DFM722 with the naked eye. 2) The typical discrimination between Soeumin and Soyangin showed statistical significance(p<0.05) in Factor PF 4(red bar) on the result of VEGA-DFM722.

• Journal of Audiology & Otology
• /
• 제24권1호
• /
• pp.10-16
• /
• 2020

Background and Objectives:The blockage of adenosine receptors by caffeine changes the levels of neurotransmitters. These receptors are present in all parts of the body, including the auditory and vestibular systems. This study aimed to evaluate the effect of caffeine on evoked potentials using auditory brainstem responses (ABRs) and cervical vestibular-evoked myogenic potentials (cVEMPs) in a double-blind placebo-controlled study. Subjects and Methods: Forty individuals (20 females and 20 males; aged 18-25 years) were randomly assigned to two groups: the test group (consuming 3 mg/kg pure caffeine powder with little sugar and dry milk in 100 mL of water), and the placebo group (consuming only sugar and dry milk in 100 mL water as placebo). The cVEMPs and ABRs were recorded before and after caffeine or placebo intake. Results: A significant difference was observed in the absolute latencies of I and III (p<0.010), and V (p<0.001) and in the inter-peak latencies of III-V and I-V (p<0.001) of ABRs wave. In contrast, no significant difference was found in cVEMP parameters (P13 and N23 latency, threshold, P13-N23 amplitude, and amplitude ratio). The mean amplitudes of P13-N23 showed an increase after caffeine ingestion. However, this was not significant compared with the placebo group (p>0.050). Conclusions: It seems that the extent of caffeine's effects varies for differently evoked potentials. Latency reduction in ABRs indicates that caffeine improves transmission in the central brain auditory pathways. However, different effects of caffeine on auditory- and vestibular-evoked potentials could be attributed to the differences in sensitivities of the ABR and cVEMP tests.

• 대한청각학회지
• /
• 제24권1호
• /
• pp.10-16
• /
• 2020

Background and Objectives:The blockage of adenosine receptors by caffeine changes the levels of neurotransmitters. These receptors are present in all parts of the body, including the auditory and vestibular systems. This study aimed to evaluate the effect of caffeine on evoked potentials using auditory brainstem responses (ABRs) and cervical vestibular-evoked myogenic potentials (cVEMPs) in a double-blind placebo-controlled study. Subjects and Methods: Forty individuals (20 females and 20 males; aged 18-25 years) were randomly assigned to two groups: the test group (consuming 3 mg/kg pure caffeine powder with little sugar and dry milk in 100 mL of water), and the placebo group (consuming only sugar and dry milk in 100 mL water as placebo). The cVEMPs and ABRs were recorded before and after caffeine or placebo intake. Results: A significant difference was observed in the absolute latencies of I and III (p<0.010), and V (p<0.001) and in the inter-peak latencies of III-V and I-V (p<0.001) of ABRs wave. In contrast, no significant difference was found in cVEMP parameters (P13 and N23 latency, threshold, P13-N23 amplitude, and amplitude ratio). The mean amplitudes of P13-N23 showed an increase after caffeine ingestion. However, this was not significant compared with the placebo group (p>0.050). Conclusions: It seems that the extent of caffeine's effects varies for differently evoked potentials. Latency reduction in ABRs indicates that caffeine improves transmission in the central brain auditory pathways. However, different effects of caffeine on auditory- and vestibular-evoked potentials could be attributed to the differences in sensitivities of the ABR and cVEMP tests.

• 동의신경정신과학회지
• /
• 제12권2호
• /
• pp.37-51
• /
• 2001

The clinical study was carried out the 43 patients with Depression who were treated in Department of Neuropsychiatry, College of Oriental Medicine, Dae Jeon University from 22 February 2000 to 14 November 2001. The results were summarized as follows. 1. The ratio of male and female was 10:33, 60's(32.6%) was frequent, no inducing factor(38.3%) was seen in a lot of cases and many patients came to our hospital by way of west-neuropsychiatry(56.8%). 2. The period of clinical history was frequent from 3 to 10 years(23.2%), the most frequent preceding disease was cardiovascular systemic disease(18.4%). 3. The main clinical symptoms were apprehension alpitation(13.4%), anorexia(9.8%), headache nuchal region stiffness(9.8%), general body weakness(6.5%), chest discomfort(6.5%), dizziness(5.7%), febris(5.3%) and constipation(5.3%). 4. The patient's tongue aspect had pink tongue and empty fur(32.6%) and pulse type had thin and deficient pulse(39.5%). The prescription drugs were Chunggansoyo-san(30.0%), purging liver and alleviating depression to regulate qi, and Guibiondam-tang(15.8%) eliminating phlegm, cooling pericardium and warming gallbladder. 5. The curve was within normal range at Psychoneural system(81.4%), and Visceral system(90.1%). 6. The regulation was Normal(48.1%), RL(27.9%), RR(20.2%) at Psychoneural system and Normal(45.9%), RL(28.5%), RR(20.3%) at Visceral system. 7. Activity and Reactivity had much lower response at 1th, 2th, 3th, 4th, 7th SANGHAN, Polalization had much higher response at 1th, 4th, SANGHAN and much lower response at 2th, 3th, 7th SANGHAN.