• Title/Summary/Keyword: Science & Technology (S&T)

Search Result 3,194, Processing Time 0.072 seconds

Sand Elimination and Microbial Depuration in Surf clam, Mactra veneriformis, Harvested from Western Coast of Korea (서해산 동죽 (Mactra veneriformis)의 토사 배출 및 미생물 정화 조건)

  • SONG Ki-Cheo1;MOK Jong-Soo;KANG Chang-Su;CHANG Dong-Suck
    • Korean Journal of Fisheries and Aquatic Sciences
    • /
    • v.34 no.3
    • /
    • pp.184-189
    • /
    • 2001
  • Surf clam, Mactra veneriformis, is a important shellfish produced in south-western coast of Korea. But it's ready to be contaminated and have sand in flesh because it mainly inhabit in silt at tHe inside of coastal area. We determined optimum conditions for the sand elimination and microbial depuration in the shellfish harvested from western coast of Korea. It was found that the most effective conditions of process water for the sand elimination were $23^{\circ}C$, $32.9-35.0\%_{\circ}$ salinity and pH $7.9\~9.0.\;A$ surf clam contained about 210 mg of sand whose $94\%$ was eliminated after 24 hours in natural sea water ($32.9\%_{\circ}$ , pH 7.9) controlled at $23^{\circ}C$. To eliminate both sand and microorganisms contaminated in surf clam, the process water should be run during at least 36 hours for the former and 24 hours for the latter at 150 L/minute/$m^3$of shellfish, when its volume was above 4,000 L/$m^3$ of shellfish in 2 tons of tank.

  • PDF

Effect of High Temperature Steam Oxidation on Yielding of Zircaloy-4 PWR Fuel Cladding -Expanding Copper Mandrel Test- (가압경수형 핵연료 피복관 지르칼로이-4의 항복현상에 대한 고온 수증기 산화의 영향 -구리 맨드렐 팽창시험법-)

  • Kye-Ho Nho;Sun-Pil Choi;Byong-Whi Lee
    • Nuclear Engineering and Technology
    • /
    • v.21 no.2
    • /
    • pp.111-122
    • /
    • 1989
  • With the Zircaloy-4 tube oxidized in high temperature (1323 K) steam for 5, 10, 30 and 60 minutes, the expanding copper mandrel test was carried out over a temperature range of 673-l173k at $\varepsilon\;=\;3.0\times10^5S\;^1$. The oxidation parameters $(K_i)$ in the present study were linearly proportional to square root of time $(Ki= \delta_{kit})$ and their rate constants ($\delta_{ki}$) are 0.281, 2.82, and 2.313 for weight gain and thickness of Zr02 and $\alpha$(0) layer, respectively. Activation energy for high temperature (873-1073k) plastic deformation of Zircaloy-4 increases from 251 KJ/mol to 323 KJ/mol with increase in oxidation time from 5 minutes to 60 minutes due to the high strengthened Zr02. With the oxide layer thickness [K ; expressed in "Equivalent Cladding Reacted" (ECR,%)] and the yield stress obtained from the mandrel test, an empirical relation was derived as ($\sigma/C)^n=K^mexp$ (Q/RT) with n=6.9, m=5.7, C=0.155, 0.138, 0.051, and 0.046 MPa for Q=251, 258, 316, 323 KJ/mol, respectively.

  • PDF

Flow Effects on Tailored RF Gradient Echo (TRFGE) Magnetic Resonance Imaging : In-flow and In-Plane Flow Effect (Tailored RF 경자사계방향 (TRFGE} 자기공명영상(MRI)에서 유체에 의한 영상신호 변화 : 유체유입효과와 영상면내를 흐르는 유체의 효과에 대하여)

  • Mun, Chi-Ung;Kim, Sang-Tae;No, Yong-Man;Im, Tae-Hwan;Jo, Jang-Hui
    • Journal of Biomedical Engineering Research
    • /
    • v.18 no.3
    • /
    • pp.243-251
    • /
    • 1997
  • In this paper, we have reported two interesting flow effects arising in the TRFGE sequence using water flow phantom. First, we have shown that the TRFGE sequence is indeed not affected by "in-flow" effect from the unsaturated spins flowing into the imaging slice. Second, the enhancement of "in-plane flow" signal in the readout gradient direction was observed when the TRFGE sequence was used without flow compensation. These two results have many interesting applications in MR imaging other than fMRI. Results obtained were also compared with the results obtained by the conventional gradient echo(CGE) imaging. Experiments were performed at 4.7T MRI/S animal system (Biospec, BRUKER, Switzerland). A cylindrical phantom was made using acryl and a vinyl tube was inserted at the center(Fig. 1). The whole cylinder was filled with water doped with $MnCl_2$ and the center tube was filled with saline which flows in parallel to the main magnetic field along the tube. Tailored RF pulse was designed to have quadratic ($z^2$) phase distribution in slice direction(z). Imaging parameters were TR/TE = 55~85/10msec, flip angle = $30^{\circ}$, slice thickness = 2mm, matrix size = 256${\times}$256, and FOV= 10cm. In-flow effect : Axial images were obtained with and without flow using the CGE and TRFGE sequences, respectively. The flow direction was perpendicular to the image slice. In-plane flow : Sagittal images were obtained with and without flow using the TRGE sequence. The readout gradient was applied in parallel to the flow direction. We have observed that the "in-flow" effect did not affect the TRFGE image, while "in-plane flow" running along the readout gradient direction enhanced the signal in the TRFGE sequence when flow compensation gradient scheme was not used.

  • PDF

Effect of Sequence Variation in Bovine Mitochondrial DNA D-Ioop Region on ~ilk Production for Hanwoo (한우 산유량에 미치는 Mitochondrial DNA D-loop영역의 염기서열 변이효과)

  • Kong, H.S.;Oh, J.D.;Lim, H.J.;Lee, H.K.;Jeon, G.J.;Yoon, D.H.;Jeon, G.J.;Choi, J.G.;Choi, Y.H.;Cho, B.W.
    • Journal of Animal Science and Technology
    • /
    • v.46 no.5
    • /
    • pp.729-734
    • /
    • 2004
  • This study was performed to analyze the sequence variations of mtDNA D-loop and their effects on milk in Hanwoo(Korean cattle). The resulting sequences were compared with previously published sequences for other cattle breeds (GenBank JOI394). The Polymerase Chain Reaction was performed to amplify a total of 964 bp between nucleotide 15758 and 383 within D-loop region of mtDNA using specific primers. Twenty polymorphic sites by nucleotide substitution were found in mtDNA D-loop region of Hanwoo. The frequencies of positions at 8, 169, 16042, 16051, 16057, 16093, 16119, 16122, 16209, 16255 and 16302 nt with high levels of sequence polymorphism were 0.150, 0.950, 0.085, 0.138, 0.106, 0.085, 0.138, 0.212, 0.085, 0.148 and 0.180, respectively. The substitution effect at 16119(p<0.1) and 16185(p< 0.05) nt was found significant on milk production. Polymorphism of mtDNA sequence in D-Ioop region could be useful for the analysis of cytoplasmic genetic variation and associations with the other economically important traits and maternal lineage analysis in Hanwoo.

A Study on the Promotion of Electronic Government and Plans for Archival Management (전자정부 추진과 기록관리방안)

  • Kim, Jae-hun
    • The Korean Journal of Archival Studies
    • /
    • no.5
    • /
    • pp.39-85
    • /
    • 2002
  • This paper is aimed at proposing the policies for managing archives in the process of promoting Electronic Government System. Although there have been many studies of electronic government project and plans for its establishment, this research examines the electronic government system and its problems on the basis of archival science. What I acquired in this paper is as follows. The development of information technology needs great changes ranging from the nation to the individuals. It becomes common that the use of computerized program for business purposes, computerization of information materials and the effective way of search use of electronic documents. Therefore, more and more countries all over the world have been seeking to promote 'Electronic Government', which applies the fruits of the development in information technology to administration process. Recently, Korea has been rapidly entered into the 'Electronic Government' system being against the traditional way of administration. In electronic government system, the 'Life Cycle' of public records will be computerized. Therefore, it is important to change and develop along with the government's policies for 'electronic government project' in the archival management system. This means that the archival management system which have put emphasis on the textual records should be converted to electronic records system. In other words, the records management in electronic government system requires not the transfer and preservation of the records but the consistent management system including the whole process of creating, appraising, arranging, preserving and using the records. So, the systematic management of electronic records plays an important role in realization of electronic government, but it is a subject to be realized by electronic government at the same time. However, the government have overlooked the importance of archival management for long time, especially the importance of electronic records management system. First of all, this research attempts to infer limits and problems through the theoretical considerations of the existing studies for electronic government and to clear up the relations between electronic government and archival management. Based on this, I'll seek to progress the study through reviewing the present condition of archival management in the process of promoting electronic government and suggesting the policies for enhancing the successful electronic government and the construction of scientific archival management system. Since early 1990, many countries in the world have been making every effort to concrete 'Electronic Government'. Using the examples in other nations, it is not difficult to recognize that the embodiment of electronic government is closely connected with the archival management policies. Korea have completed legal and institutional equipments including the new establishment of "Electronic Government Law" to realize electronic government. Also, Korea has been promoting electronic government with the Ministry of Government Administration and Home Affairs and Government Computer Center as a leaders. Though managing records, especially the management of electronic records is essential in electronic government system, we haven't yet discussed this section in Korea. This is disapproved by the fact the Government Archives and Records Service has played little role in promoting electronic government project. There are two problems relating this environment. First, present system can't meet the consistent 'Life Cycle' ranging from the creation to the preservation of electronic records. Second, the 'Life Cycle' of electronic records is divided into two parts and managed separately by GCC and GARS. The life of records is not end with the process raged from creation to distribution. On the other hand, the records are approved their value only whole procedures. Therefore, GARS should play a deading role in designing and establishing the archival management system. The answer to these problems, is as follows. First, we have to complete the electronic records management system through introducing ERMS not EDMS. This means that we should not change and develop towards ERMS simply with supplementing the current electronic records management system. I confirm that it is important and proper to establish ERMS system from the very beginning of the process of promoting electronic government. Second, I suggest the developmental integration of GARS and GCC. At present, the divided operations of GCC and GARS, the former is in charge of the management center for electronic business and the latter is the hub institution of managing nation's records and archives result in many obstacles in establishing electronic government system and accomplishing the duties of systematic archival management. Therefore, I conclude that the expansive movement towards 'National Archives' through the integration among the related agencies will make a great contribution to the realization of electronic government and the establishment of archival management system. In addition to this, it will be of much help to constitute and operate the 'Task Force' regarding the management of electronic records with the two institution as the central figures.

Comparison of Acceptance of Disability, Stress, Coping Methods, and Wellness between Mothers of Physical Dysfunctional or Developmental Disabilities (신체기능장애와 발달장애아동 어머니의 장애수용, 스트레스, 대처방식 및 웰니스)

  • Kang, Ji-Soon;Hwang, Ji-Won;Kim, Jung-Aa
    • Journal of the Korean Applied Science and Technology
    • /
    • v.36 no.4
    • /
    • pp.1385-1398
    • /
    • 2019
  • This study was a survey study to provide the base data necessary to prepare efficient management plans for the mothers with disabled children by type, comparing degrees of disability acceptance, stress, coping method and wellness between mothers with physical functional disordered children and developmental disordered children. The study subjects were a mother who raises disordered children. Data collection was conducted from October 2018 to April 2019, and differences between the two groups were analyzed as t-test, ANOVA, and Pearson correlation. In results, Studies have shown that there are differences between the two groups as mothers with physical functional disordered children and mothers with developmental disordered children as degrees of disability acceptance, stress, treatment and wellness. Disability acceptance and coping method of mothers with physical functional disordered children (r=0.23, p=.033), disability acceptance and Wellness (r=0.51, p<.001) have shown positive correlations and disability acceptance and stress (r=-0.72, p<.001) have shown negative correlations. Disability acceptance and wellness (r=0.40, p<.001) of the mother with a developmental disordered child have shown a significant positive correlation, and disability acceptance and stress (r=-0.71, p<.001) have shown a significant negative correlations. The higher the degree of disability acceptance, the lower the stress level and the higher the coping method and wellness mothers with physical functional disordered children had. The higher disability acceptance, the lower stress degrees and the higher wellness degrees mothers with developmental disordered children had. In order to improve disability acceptance by mothers with physical functional disordered children, it was necessary to improve both coping methods and wellness with stress reducing strategy, while the mother with developmental disordered children were needed strategies to reduce stress and improve wellness.

A Study on BMI, Diet Perception and Dietary Behavior of Female University Students (여대생의 체질량지수, 다이어트 인식과 다이어트 행동에 관한 연구)

  • Lee, JinHee
    • Journal of the Korean Applied Science and Technology
    • /
    • v.37 no.3
    • /
    • pp.463-472
    • /
    • 2020
  • The purpose of this study is to identify the BMI, diet perception and diet behavior of female university students. A descriptive survey design was used 165 students from October 29 to November 9, 2018. Data were analyzed using mean, t-test, ANOVA, cross analysis with SPSS 21.0. Total diet perception was 3.44 points, highest sub category was 'practice' with 4.00 points, followed by 'information and education' with 3.58 points, 'necessity' with 3.32 points and lowest category was 'self-recognition' with 2.84. 65 students(43.0%) were 'less than three times' in 'Number of diets' and diet methods was 65(43.0%) for 'food control' and 62(41.1%) for 'exercise'. During in a week, 98 students(84.9%) exercised within three hours, followed by 33(21.9%) who did not exercised at all. 22 students(14.6%) said they experienced damage from dieting, while the types included gastrointestinal disease, menstrual irregularity and hair loss. The total score of diet perception according to BMI was lower in the underweight group than in the normal and overweight groups(p<.001). In diet 'practice' category, low weight group scored lower than normal weight and overweight groups(p<.05). In 'information and education' category, overweight group scored the highest, followed by normal and underweight groups(p<.001). In diet 'necessity' and 'self-recognition' categories, low weight group scored lower than normal weight and overweight groups(p<.001). Diet behavior by diet perception was different in number and method of diet(p<.001). Based on the results, it is thought that attention and education are needed to form a proper diet perception and maintain healthy living for female university students.

Effects of Fasting and Handling Stress on Plasma Concentrations of Glucose, Stress-associated Enzymes and Carcass Quality of Market Pigs (절식과 출하취급이 출하돈의 스트레스 관련 혈액성상과 도체품질에 미치는 영향)

  • Kim, D.H.;Ha, D.M.;Seo, J.T.
    • Journal of Animal Environmental Science
    • /
    • v.13 no.2
    • /
    • pp.81-88
    • /
    • 2007
  • One hundred and forty-four cross-bred market pigs weighing approximately 110 kg were randomly divided into six groups in a 3 (duration of fasting prior to loading; 0, 12 and 24 h) ${\times}$ 2 (handling stress; minimal vs stimulated handling stress) factorial arrangement of treatments. The stimulated handling stress group received overally rough handling including electric prod stimulation during loading, transport and lairage at least once at each step. All the animals received 3-h lairage prior to slaughter. Blood and longissimus dorsi muscle (LM) samples were taken at slaughter and after overnight chilling of the carcass, respectively. Mean plasma glucose concentration, as expected, was less in the 12 h- or 24 h-fasting group than in the 0 h-fasting, whereas cortisol concentration was greater (P<0.05) in the 24 h- vs 0 h-fasting group. Plasma concentrations of stress indicators glucose, cortisol, creatine kinase and lactate dehydrogenase were greater in the stimulated vs minimal handling stress group. There were no interactions between the duration of fasting and handling stress in their effects on these blood variables. The incidence of pale, soft and exudative (PSE) carcass and drip loss of LM were reduced in the 12 h- or 24 h- vs 0 h-fasting group, whereas the 24-h postmortem LM pH and color including the lightness and redness were not affected by the duration of fasting. The incidence of PSE carcass and physicochemical characteristics of LM, however, were not changed by the stimulated vs minimal handling stress. In conclusion, results suggest that fasting the market pig overnight prior to transport is desirable in terms of reducing the incidence of PSE carcass. Rough handling of market pigs may not affect the carcass quality of the animals when an enough lairage time is provided. However, rough handling inflicts a stimulated stress on the animal, which is manifested by increased blood concentrations of stress indicators, and therefore should be avoided fer animal welfare.

  • PDF

Hypoglycemic Effects of Fruits and Vegetables in Hyperglycemic Rats for Prevention of Type-2 Diabetes (고혈압쥐의 과일과 야채의 섭취에 따른 저혈당 효과)

  • Survay, Nazneen Shaik;Ko, Eun-Young;Upadhyay, Chandrama Prakash;Jang, Mi;Park, Se-Won;Lee, Dong-Ha;Jung, Yi-Sook;Yoon, Do-Young;Hong, Sae-Jin
    • Horticultural Science & Technology
    • /
    • v.28 no.5
    • /
    • pp.850-856
    • /
    • 2010
  • An in vivo oral glucose tolerance test (OGTT) was performed on hyperglycemic male Sprague-Dawley rats to assess the effect of fruits and vegetables ($1g{\cdot}kg^{-1}$ body weight) on blood glucose levels (${\Delta}BGLs$) at different time intervals of 0, 5, 15, 30, 60, 90 and 120 min. The areas under glucose curve (${\Delta}AUCs$) were calculated at 120 min of OGTT by trapezoid method. Total phenolic content (TPC) and anti-oxidant activity (AOA) of fruits and vegetables were assayed in vitro by Folin Ciocalteu and DPPH (2, 2-diphenyl-1-picrylhydrazyl) methods, respectively. At the end of the experiment the correlations among the parameters TPC, AOA and ${\Delta}AUC$ was estimated by Pearson's correlations. Among fruit crops, tangerine, plum, grape and pear and among vegetables, blue leaf mustard, cabbage, chicory, broccoli and others exhibited significant hypoglycemic effects by reducing ${\Delta}BGLs$ with significant ${\Delta}AUC$. The effective ${\Delta}AUC$ ranged from $5548.2{\pm}462.1$ to $3823.3{\pm}282.0mg-min{\cdot}dL^{-1}$. The TPC and AOA ranged from $0.063{\pm}0.00$ to $0.913{\pm}0.14mg{\cdot}g^{-1}$ GAE and $01.05{\pm}0.08$ to $75.46{\pm}0.06%$, respectively. Overall, six fruits and fifteen vegetables exhibited higher TPC and one fruit and four vegetables exhibited higher AOA. There was a better correlation among TPC, AOA and ${\Delta}AUC$ of fruits and TPC & AOA of vegetables. We report that hypoglycemically significant fruits and vegetables investigated in this study have pharmacological importance which reduced ${\Delta}BGLs$ through insulin like activity and AOA in prevention of type-2 diabetes.

Development of a 2-fluid Jet Mixer for Preventing the Sedimentation in Livestock Liquid Manure Storage Tank (가축분뇨액비저장조 침전물 퇴적 방지를 위한 2류체 제트노즐식 교반장치 개발에 관한 연구)

  • Yu, B.K.;Hong, J.T.;Kim, H.J.;Kweon, J.K.;Oh, K.Y.;Park, B.K.
    • Journal of Animal Environmental Science
    • /
    • v.18 no.3
    • /
    • pp.207-220
    • /
    • 2012
  • There are around 7,500 manure tanks to treat the manures from pigs in Korea. In the tank, there are too much sediments deposited on the base and wall, which causes low efficiency of stock capacity and manure fermentation. In order to minimize sediments and to ferment manure effectively, we developed a 2-fluid jet mixer for mixing sediments in liquid livestock manure tank. For developing the prototype, we tested a factorial experimental system with various nozzles, and simulated CFD models with two kinds of nozzle arrangement. From the results of factorial experiment and CFD simulation, we concluded the dia. ratio of primary : secondary nozzle should be 1:2 and the nozzles should be arranged at the same distances toward to the circumferential direction. With this results, we manufactured a 2-fluid jet mixer which is consists of four 2-phase nozzles, centrifugal slurry pump and root's type air blower. And, we carried out the performance test of the prototype in the round shaped liquid manure tank in the farm. The performance test results showed that the uniformity of TS (Total Solid) and VS (Volatile Solid) was raised from 21.3 g/L, 13.3 g/L In steady state to TS and VS to 23.0 g/L, 14.1 g/L in the mixing operation. Therefore, we could conclude that the prototype of 2-fluid mixer could make the solid material which could be sediments in the tank not to be deposited in the tank and to be contacted to air bubbles which could enhance the efficiency of the fermentation of livestock manure.