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Seedling Plug and Cutting Method for Multi-propagation of Ornamental Miscanthus Spp. (조경용 억새의 대량번식을 위한 플러그묘와 삽목번식법)

  • Hwang, Kyung Sik;Joo, Song Tak;Ha, Soo Sung;Kim, Ki Dong;Joo, Young Kyoo
    • Weed & Turfgrass Science
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    • v.7 no.3
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    • pp.275-282
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    • 2018
  • Miscanthus species are known as a genus of eco-friendly and low-maintenance cost ornamental grasses. Plug and cutting methods were tested for multi-propagation of most promising ornamental Miscanthus species in greenhouse and field plot. The plug formation period with three different cell sizes with four cultivars (M. sinensis 'Andersson', 'Strictus', 'Gracillimus', 'Variegatus') were evaluated the seedling development stages with two irrigation types of the over-head and the bottom watering in greenhouse and field plot afterward during 2015-2016 season. In seedling plug test, the size of tray cell affected the plug formation. Bottom irrigation resulted positively on plant height, weight, root and tiller development compared with the over-head irrigation. Plug cell size affected the plant growth in the field after transplanting. All of the 3 Miscanthus species showed higher rates of successful propagation at the lower nodes before inflorescence formation (vegetative growth stage). To analyze the survival factors of M. xgiganteus cutting, the cutting time, node part, and culm diameter were tested as independent variables with the binary logistic model. The survival probability was influenced by node part and culm diameter significantly. The third and fifth node parts showed 0.12 (8X higher failure probability) and 0.02 (50X higher failure probability) times less survival probability. It means the survival probability will be increased by using older and lower part of cuttings during a vegetative growth stage before inflorescences of M. xgiganteus.

The intrinsic instabilities of fluid flow occured in the melt of Czochralski crystal growth system

  • Yi, Kyung-Woo;Koichi Kakimoto;Minoru Eguchi;Taketoshi Hibiya
    • Proceedings of the Korea Association of Crystal Growth Conference
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    • 1996.06a
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    • pp.179-200
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    • 1996
  • The intrinsic instabilities of fluid flow occurred in the melt of the Czochralski crystal growth system Czochralski method, asymmetric flow patterns and temperature profiles in the melt have been studied by many researchers. The idea that the non-symmetric structure of the growing equipment is responsible for the asymmetric profiles is usually accepted at the first time. However further researches revealed that some intrinsic instabilities not related to the non-symmetric equipment structure in the melt could also appear. Ristorcelli had pointed out that there are many possible causes of instabilities in the melt. The instabilities appears because of the coupling effects of fluid flow and temperature profiles in the melt. Among the instabilities, the B nard type instabilities with no or low crucible rotation rates are analyzed by the visualizing experiments using X-ray radiography and the 3-D numerical simulation in this study. The velocity profiles in the Silicon melt at different crucible rotation rates were measured using X-ray radiography method using tungsten tracers in the melt. The results showed that there exits two types of fluid flow mode. One is axisymmetric flow, the other is asymmetric flow. In the axisymmetric flow, the trajectory of the tracers show torus pattern. However, more exact measurement of the axisymmetrc case shows that this flow field has small non-axisymmetric components of the velocity. When fluid flow is asymmetric, the tracers show random motion from the fixed view point. On the other hand, when the observer rotates to the same velocity of the crucible, the trajectory of the tracer show a rotating motion, the center of the motion is not same the center of the melt. The temperature of a point in the melt were measured using thermocouples with different rotating rates. Measured temperatures oscillated. Such kind of oscillations are also measured by the other researchers. The behavior of temperature oscillations were quite different between at low rotations and at high rotations. Above experimental results means that the fluid flow and temperature profiles in the melt is not symmetric, and then the mode of the asymmetric is changed when rotation rates are changed. To compare with these experimental results, the fluid flow and temperature profiles at no rotation and 8 rpm of crucible rotation rates on the same size of crucible is calculated using a 3-dimensional numerical simulation. A finite different method is adopted for this simulation. 50×30×30 grids are used. The numerical simulation also showed that the velocity and flow profiles are changed when rotation rates change. Futhermore, the flow patterns and temperature profiles of both cases are not axisymmetric even though axisymmetric boundary conditions are used. Several cells appear at no rotation. The cells are formed by the unstable vertical temperature profiles (upper region is colder than lower part) beneath the free surface of the melt. When the temperature profile is combined with density difference (Rayleigh-B nard instability) or surface tension difference (Marangoni-B nard instability) on temperature, cell structures are naturally formed. Both sources of instabilities are coupled to the cell structures in the melt of the Czochralski process. With high rotation rates, the shape of the fluid field is changed to another type of asymmetric profile. Because of the velocity profile, isothermal lines on the plane vertical to the centerline change to elliptic. When the velocity profiles are plotted at the rotating view point, two vortices appear at the both sides of centerline. These vortices seem to be the main reason of the tracer behavior shown in the asymmetric velocity experiment. This profile is quite similar to the profiles created by the baroclinic instability on the rotating annulus. The temperature profiles obtained from the numerical calculations and Fourier transforms of it are quite similar to the results of the experiment. bove esults intend that at least two types of intrinsic instabilities can occur in the melt of Czochralski growing systems. Because the instabilities cause temperature fluctuations in the melt and near the crystal-melt interface, some defects may be generated by them. When the crucible size becomes large, the intensity of the instabilities should increase. Therefore, to produce large single crystals with good quality, the behavior of the intrinsic instabilities in the melt as well as the effects of the instabilities on the defects in the ingot should be studied. As one of the cause of the defects in the large diameter Silicon single crystal grown by the

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A Study on the Concentration of Hippuric Acid in Urine of Workers Exposed to Toluene (톨루엔에 폭로된 근로자의 뇨중 마뇨산량에 관한 연구)

  • Park, Eun-Mi;Roh, Jae-Hoon;Moon, Young-Hahn
    • Journal of Preventive Medicine and Public Health
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    • v.20 no.2 s.22
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    • pp.228-235
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    • 1987
  • The objective of this study is to examine the correlation between the toluene concentration in the work environment of organic solvents and the concentration of hippuric acid in urine of workers exposed toluene, and to acquire the fundamental materials of workers' health care and to assist the assessment of the biological permisible exposure limit. The control groups are 72 workers who had never been exposed to toluene and the case groups are 101 workers who had been exposed to toluene. This study was conducted to examine the correlation between the concentration of toluene in work environment and workers' hippuric acid concentration, to investigate the complaint difference of subjective symptoms by means of questionaire, between the case groups and control groups. The results and conclusions are as fellows: 1) The highest mean concentration of toluene in the air is $544.13{\pm}7.75ppm$ in the Printing Department of mixing organic solvents. The concentrations of the others are $463.27{\pm}5.24ppm$ in Department of mixture for organic solvents, and $393.56{\pm}45.69ppm$ in the Printing Department(1), and $248.38{\pm}45.16ppm$ in the Printing Department(2), and $159.38{\pm}18.51ppm$ in the Printing Department(3). 2) The highest mean concentration of hippuric acid in urine is $6034.84{\pm}1298.35mg/l$ in the Printing Department with mixing organic solvents. The concentrations of the others are $4798.44{\pm}784.53mg/l$ in Department of mixture of organic solvents, and $2883.06{\pm}701.90mg/l$ in the Printing Department(1), and $1449.98{\pm}905.19mg/l$ in the Printing Department(2), and $598.52{\pm}299.43mg/l$ in the Printing Department(3). 3) As the toluene concentration in the work environment becomes higher, the concentration of hippuric acid in urine also becomes higher. It is found that the coefficient of correlation between toluene concentration and the concentration of hippuric acid are positive (r=0.868, Y=7.18X+349.57) 4) It is found that the case groups complain of much more subjective symptoms than the control groups.

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The Study of Affecting Image Quality according to forward Scattering Dose used Additional Filter in Diagnostic Imaging System (부가필터 사용 시 전방 산란선량에 따른 화질 영향에 대한 연구)

  • Choi, Il-Hong;Kim, Kyo-Tae;Heo, Ye-Ji;Park, Hyong-Hu;Kang, Sang-Sik;Noh, Si-Cheol;Park, Ji-Koon
    • Journal of the Korean Society of Radiology
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    • v.10 no.8
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    • pp.597-602
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    • 2016
  • Recent clinical field utilizes the aluminium filter in order to reduce the low-energy photons. However, the usage of the filter can cause adverse effect on the image quality because of the scattered dose that is generated by X-ray hardening phenomenon. Further, usage of filter with improper thickness can be a reason of dose creep phenomenon where unnecessary exposure is generated towards the patient. In this study, the author evaluated the RMS and the RSD analysis in order to have a quantitative evaluation for the effect of forward scattering dose by the filter on the image. as a result of the study, the FSR and the RSD was increased together with the increasing of thickness of the filter. In this study the RSD means the standard deviation of the mean value is relatively size. It can be understood that the signal-to-noise ratio decreases when the average value is taken as a signal and the standard deviation is judged as a noise. The signal-to-noise ratio can understanding as index of resolution at image. Based on these findings, it was quantitatively verified that there is a correlation of the image quality with the FSR by using an additional filter. The results, a 2.5 mmAl which is as recommended by NCRP in the tube voltage of 70 kVp or more showed the 14.6% on the RSD when the filter was not in used. these results are considered able to be utilized as basic data for the study about the filter to improve the quality of the image.

Analysis of Bacterial Contamination on Surface of General Radiography Equipment and CT Equipment in Emergency Room of Radiology (영상의학과 응급실내의 일반촬영장비와 전산화단층촬영장비 표면에서의 세균 오염에 관한 분석)

  • Hong, Dong-Hee;Kim, Hyeong-Gyun
    • Journal of radiological science and technology
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    • v.39 no.3
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    • pp.421-427
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    • 2016
  • We aim to offer basic materials about infection management through conducting bacterial contamination test about general radiography equipment and CT equipment installed in ER of three general hospitals with 100 sickbeds or more located in Gyeongsangbuk-do Province, and suggest management plan. It had been conducted from 1st December 2015 to 31st December, and objects were general radiography equipment and CT equipment of emergency room located in Gyeongsangbuk-do Province. For general radiography equipment, sources were collected from 4 places such as upper side of control box which employees use most, upper side of exposure button, whole upper side of table which is touching part of patient's skin, upper side of stand bucky's grid, and where patients put their jaws on. For CT equipment, sources were collected from 3 places such as upper side of control box which radiography room employees use most, X-ray exposure button, whole upper side of table which is touching part of patient's skin, and gantry inner. Surface contamination strain found at general radiography equipment in emergency room of radiology are Providencia stuartii(25%), Stenotrophomonas maltophilia(18%), Enterobacter cloacae(8%), Pseudomonas species(8%), Staphylococcus epidermidis(8%), Gram negative bacilli(8%), and ungrown bacteria at incubator after 48 hours of incubation (67%) which is the biggest. Most bacteria were found at upper side of stand bucky-grid and stand bucky of radiology's general radiography equipment, and most sources of CT equipment were focused at patient table, which means it is contaminated by patients who have various diseases, and patients who have strains with decreased immunity may get severe diseases. Thus infection prevention should be made through 70% alcohol disinfection at both before test and after test.

Effect of Supportive Nursing Intervention on Hopelessness, Self-Esteem, Self-Concept of Operative Patient with Head and Neck Cancer (전인적 지지간호중재가 두경부암 수술환자의 절망감, 자아존중감 및 자아개념에 미치는 효과)

  • Seok, Jung-Hee;Kang, Eun-Sil;Choi, Hwa-Sook
    • Journal of Hospice and Palliative Care
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    • v.7 no.2
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    • pp.189-199
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    • 2004
  • Purpose: Despite the small incidence, head and neck cancer may cause a wide range of physical transformation by surgical operation, damage to active functions such as eating and speaking. It may provoke hopelessness, change self-esteem and self-concept after its operation, influencing the quality life of head and neck cancer patients. Thus nursing intervention should be developed to provide supportive nursing for head and neck cancer patients and play roles as competent supporters. Methods: This study was a nonequivalent, control group, pretest-posttest, non-synchronized quasi-experimental research designed to determine how supportive nursing intervention effects on hopelessness, self-esteem and self-concept of head and neck cancer patients. Subjects of the study included 40 adult inpatients of K University hospital in Pusan who were diagnosed as having head and neck cancer and operated. They were divided into experimental and comparison groups, each consisting of 20 members. The data were collected during the period from December 1, 1999 to April 11, 2000. Tools of the study included the protocol of supportive nursing intervention which was developed by researcher by means of reference, literal review and expert's advice. The measurement tool of hopelessness was translated by Won was the device of hopelessness self-evaluation from Beck, the tool for self-esteem measurement was developed by Rosenberg and translated by Kim, and the device of self-concept used by Lee et al, modified by Lee were used respectively. Data were analyzed using the SPSS/PC 9.0 program. The homogeneity of the subjects were tested using $x^2-test$ and t-test. 3 hypotheses were tested using t-test. Results: The results of the study can be summarized as follows. 1. The third hypothesis that the experimental group receiving supportive nursing intervention showed a little hopelessness than the control group not receiving supportive nursing intervention was supported (t=4.550, P=.000). 2. The third hypothesis that the experimental group receiving supportive nursing intervention showed more self-esteem than the control group not receiving supportive nursing intervention was supported (t=-6.40, p=.000). 3. The third hypothesis that the experimental group receiving supportive nursing intervention showed more self-concept than the control group not receiving supportive nursing intervention was supported (t=-6.065, P=.000). Conclusion: Supportive nursing intervention was effective nursing intervention strategy for reducing hopelessness and increasing self-esteem and self-concept of head and neck cancer patients. Then the quality of life of head and neck cancer patients can be enhanced by providing supportive nursing intervention in nursing practice.

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Comparative Study of Intrauterine Irrigation and Intravenous Injection with Cephradine at Cesarean Section (제왕절개술시 감염예방을 위한 Cephradine자궁내 세척법과 정맥내 주입법의 비교연구)

  • Choi, Jai-Dong;Kim, Jong-Wook;Lee, Tae-Hyung;Park, Wan-Seok;Lee, Sung-Ho;Chung, Wun-Yong
    • Journal of Yeungnam Medical Science
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    • v.2 no.1
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    • pp.203-210
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    • 1985
  • Febrile morbidity after cesarean section is one of the major problems in obstetric practice. This morbidity is most often due to endometritis. Although parenteral prophylactic antibiotics or antibiotic irrigation has been reported to reduce the incidence of endometritis after cesarean section, its incidence remains high. Among the patients who were undergoing cesarean section at Yeungnam University Hospital from the beginning of March, 1985, three group were evaluated in the orders. 1) 30 cases as intrauterine irrigation group with cephradine solution, 2) 35 cases as intravenous injection group with cephradine, 3) 35 cases as control group are neither irrigated nor injected. Febrile morbidity was also evaluated by means of a fever index. The incidence of clinically diagnosed endometritis in the three group were 6.7%, 2.9%, and 22.9%. As these results, two study groups were markedly reduced the incidence of endometritis than control group. There was no significant difference between the intrauterine irrigation with cephradine and control, but significant difference between the intravenous cephradine injection and control (P<0.05). With the results of fever index analysis, both prophylactic intrauterine irrigation and intravenous injection markedly reduce the incidence of endometritis after cesarean section with stastical significance (P<0.05), and also markedly reduce the febrile degree.

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Synthesis and Electrochemical Properties of Carbon Coated Li4Ti5O12 using PVC (PVC를 원료로 탄소코팅한 Li4Ti5O12의 합성 및 전기화학적 특성)

  • Hyun, Si-Cheol;Na, Byung-Ki
    • Clean Technology
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    • v.24 no.1
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    • pp.77-84
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    • 2018
  • In this study, $Li_4Ti_5O_{12}$ anode materials for lithium ion battery were synthesized by dry ball-mill method. Polyvinyl chloride (PVC) as a carbon source was added to improve electrochemical properties. When the PVC was added after $Li_4Ti_5O_{12}$ formation, the spinel structure was well synthesized and it was confirmed by X-ray diffraction (XRD) experiments. When the carbon material was added before the synthesis and the heat treatment was performed, it was confirmed that a material having a different crystal structure was synthesized even when a small amount of carbon material was added. In the case of $Li_4Ti_5O_{12}$ without the carbon material, the electrical conductivity value was about $10{\mu}S\;m^{-1}$, which was very small and similar to that of the nonconductor. As the carbon was added, the electrical conductivity was greatly improved and increased up to 10,000 times. Electrochemical impedance spectroscopy (EIS) analysis showed that the size of semicircle corresponding to the resistance decreased with the carbon addition. This indicates that the resistance inside the electrode is reduced. According to the Cyclic voltammetry (CV) analysis, the potential difference between the oxidation peak and the reduction peak was reduced with carbon addition. This means that the rate of lithium ion insertion and deinsertion was increased. $Li_4Ti_5O_{12}$ with 9.5 wt% PVC added sample showed the best properties in rate capabilities of $180mA\;h\;g^{-1}$ at 0.2 C-rate, $165mA\;h\;g^{-1}$ at 0.5 C-rate, and $95.8mA\;h\;g^{-1}$ at 5 C-rate.

Airway Responses to Bronchoprovocation Using High-Resolution Computed Tomography in Patients with Bronchial Asthma (기관지천식환자에 있어서 고해상도 전산화단층촬영술을 이용한 기관지유발에 대한 기도의 반응)

  • Choi, Byoung-Whui;Kang, Yoon-Jeong;Ko, Hyung-Ki;Park, In-Won;Hue, Sung-Ho;Kim, Yang-Soo;Kim, Young-Goo;Kim, Kun-Sang;Kim, Jong-Hyo
    • Tuberculosis and Respiratory Diseases
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    • v.42 no.6
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    • pp.813-822
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    • 1995
  • Background: Bronchial hyperresponsiveness and abnormal response such as a loss of distensibility are pathophysiologic characteristics if bronchial asthma. The only means of direct in vivo measurement of airway size had been a tantalium bronchography, until high-resolution computed tomography(HRCT) enabled to measure noninvasively two dimensional airway area more accurately and reliably. Method: To investigate airway area responses to bronchial provocation with methacholine and evaluate the major sites of bronchial constriction in patients with bronchial asthma. We examined HRCT scans in five patients with bronchial asthma who had significant bronchoconstriction(20% or more decrease in $FEV_1$) using CT scanner(5,000T CT, Shimadzu Co, Japan) before and in 3~5 min. after methacholine inhalation. Airways which were matched by parenchymal anatomic landmarks in each patient before and after methacholine inhalation were measured using film scanner(TZ-3X scanner; Truvel Co. Chatsworth CA, USA) and a semiautomated region growing method. Results: 1) We identified 9 to 12 airways in each patient which were matched by parenchymal anatomic landmarks before and after methacholine inhalation. 2) Airway responses to methacholine are quite different even in a patient. 3) The constriction of small airways(average diameter <2 mm; area < $3.14mm^2$) was 48.7%(8.3; SEM, n=43), being more prominant than that of large airways(average diameter >2 mm; area > $3.14mm^2$), 53.8% (4.4;SEM, n=10), but not significantly different(p>0.05). 4) There was no significant difference in the degree of constriction between upper(44.3% +5.8; mean + SEM, n=30) and lower lung regions(56.7% +4.5, n=23). Conclusions: Thus airway responses to methacholine bronchoprovocation is quite variable in a patient with bronchial asthma and has no typical pattern in patients with bronchial asthma.

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Ground Security Activities for Prevention of Aviation Terrorism -Centered on San Francisco International Airport of the U.S.A.- (항공테러방지를 위한 지상 보안활동 -미국 샌프란시스코국제공항을 중심으로-)

  • Kang, Maeng-Jin;Kang, Jae-Won
    • The Journal of the Korea Contents Association
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    • v.8 no.2
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    • pp.195-204
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    • 2008
  • With the growth of airline management, as well as computer and IT security, the international trade in this modern society has been rapidly increasing, Along with the advancing, airplanes have become a universal means of communication. However, the complications associated with airplane safety have also been brought up as a result, the most concerning of which is terrorism. One of the main counterplans for preventing terrorism is Ground security activities the core of Ground security activities is absolute safety for passengers in both passenger terminal and freight terminal. Subastral security refers to physical protection, proximity control and 100% security search and freight guarding of the passengers' possessions, and the personnel's duties to perform such jobs are be! coming more crucial. On the other hand, Airport security check has bee n gradually developing since the 1960's, when hijacking began to take place. Although the airports have been providing more safe and comfortable services to their customers, terrorism is still happening today. When Ground security activities is minute, the users feel displeasure and discomfort, yet considering solely their convenience can brings problems in achieving safety. Since the 9.11 terror in 2001, the idea of improving and strengthening airport security was reinforced and a considerable amount of estate is being spent today for invention and application of new technology. Various nations, including the United States, have been improving their systems of security through public services; public police department is actively carrying out their duties in airports as well. In San Francisco International Airport, private police department is in charge of collection of data, national events, VIP protection, law enforcement, cooperation within facilities, daily-based patrol and traffic control. Under guidance and supervision of national organizations, such as TSA, general police department interprets X-Rays, operates metal detectors, checks passports or IDs and observes reactions to explosives. Under these circumstances, studies about advancement of cooperation and duties of general police department and private police department necessitated: especially about private police department and their training for searching equipments, decrease in number of turn over rate, invention of technology and prior settlement in estate for security. The privacy of the public, who make up the major population of airport passengers, must also be minimized. In the following research, the activities of police departments in San Francisco International Airport will be analyzed in order to understand recent actions of the United States on airport security.