• 제목/요약/키워드: self-limiting

검색결과 239건 처리시간 0.024초

원추형(圓錐型) 탈곡기(脱糓機)에 관(關)한 연구(硏究) (Study on Cone Type Thresher (I))

  • 이승규
    • Journal of Biosystems Engineering
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    • 제6권1호
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    • pp.48-59
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    • 1981
  • The major limiting factor on the determination of combine capacity is the frequent occurence of clogging over the some parts of machine when the crop is wet in the case of Japanese self-feeding type combine. And in the case of American conventional combine having big separating parts, the great grain loss and damage occur when the machine is used for rice harvesting. This experiment was carried out to develop the new type threshing and separating equipment. Proto-type thresher which consist of a conical threshing drum and a conical separating sieve rotating around the threshing cone was constructed and tested. In the case of 800 rpm of threshing cone speed, average threshing loss was below 1 percent, separating loss was about 1 percent, grain damage was about 0.4 percent, and average total power required was about 2.6 PS. This design has some problems such as higher power required or wrapping problems under the conditions of feeding long damp straw. But, compared with the conventional combine or thresher, this machine certainly has some potentials for this approach to combine development. The crop feed rate must be increased through improvement of the feeding portion of the threshing cone. And it is required to investigate further about some parameters causing wrapping phenomena.

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Clinical evaluation of a rapid diagnostic test kit for detection of canine coronavirus

  • Yoon, Seung-Jae;Seo, Kyoung-Won;Song, Kun-Ho
    • 대한수의학회지
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    • 제58권1호
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    • pp.27-31
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    • 2018
  • Canine coronavirus is a single-stranded RNA virus that causes enteritis in dogs of any age. Coronaviral enteritis is seldom definitively diagnosed, since it is usually much less severe than many other types of enteritis and is self-limiting. Conventional diagnostics for the canine coronaviral enteritis such as polymerase chain reaction (PCR), virus isolation, and electron microscopic examination are inappropriate for small animal clinics due to the complicated experimental processes involved. Therefore, a commercially available lateral flow test kit based on chromatographic immunoassay techniques was tested to evaluate its performance as a first-line diagnostic test kit that could be used in clinics. The coronavirus antigen test kit detected canine coronavirus-infected dogs with 93.1% sensitivity and 97.5% specificity. The detection limit of the test kit was between $1.97{\times}10^4/mL$ and $9.85{\times}10^3/mL$ for samples with a 2-fold serial dilution from $1.25{\times}10^6\;TCID_{50}$ ($TCID_{50}$, 50% tissue culture infectious dose). Additionally, the test kit had no cross-reactivity with canine parvovirus, distemper virus, or Escherichia coli. Overall, the commercially available test kit showed good diagnostic performance in a clinical setting, with results similar to those from PCR, confirming their potential for convenient and accurate use in small animal clinics.

FDG PET-CT에서 악성림프종처럼 보이는 복부 기쿠치병 (Intra-abdominal Kikuchi's Disease Mimicking Malignant Lymphoma on FDG PET-CT)

  • 한혜숙;김기현;조영심;주혜진;이옥준;류동희;이기형;김승택
    • Nuclear Medicine and Molecular Imaging
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    • 제43권4호
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    • pp.363-365
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    • 2009
  • Kikuchi's disease is a self-limiting benign disease characterized by cervical lymphadenopathy, but it can be mistaken for malignant disease, and when involved lymph nodes are unusually located, diagnosis can be more difficult. The authors report the case of a 19-year-old man with Kikuchi's disease, who had isolated intra-abdominal lymphadenopathy and increased 18-fluoro-deoxyglucose (FDG) uptake in positron emission tomography-computed tomography (PET-CT). Although its incidence is extremely rare, intra-abdominal Kikuchi's disease with increased FDG uptake in PET-CT image should be considered in the differential diagnosis when constitutional symptoms mimic those of malignant lymphoma.

Fabrication of Organic-Inorganic Nano Hybrid Superlattice Thin Films by Molecular Layer Deposition

  • Cho, Bo-Ram;Yang, Da-Som;Sung, Myung-M.
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2011년도 제40회 동계학술대회 초록집
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    • pp.115-115
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    • 2011
  • Nano hybrid superlattices consisting of organic and inorganic components have great potential for creation of new types of functional material by utilizing the wide variety of properties which differ from their constituents. They provide the opportunity for developing new materials with new useful properties. Herein, we fabricated new type of organic-inorganic nano hybrid superlattice thin films by a sequential, self-limiting surface chemistry process known as molecular layer depostion (MLD) combined with atomic layer deposition (ALD). An organic layer was formed at $150^{\circ}C$ using MLD with repeated sequintial adsorption of Hydroquinone and Titanium tetrachloride. A $TiO_2$ inorganic nanolayer was deposited at the same temperature using ALD with alternating surface-saturating reactions of Titanium tetrachloride and water. Using UV-Vis spectroscopy, we confirmed visible light absorption by LMCT. And FTIR spectroscopy and XPS were employed to determine the chemical composition. Ellipsometry and TEM analysis were also used to confirm linear growth of the film versus number of MLD cycles at all same temperature. In addition, p-n junction diodes domonstrated in this study suggest that the film can be suitable for n-type semiconductors.

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Diurnal gene expression of $Period2$, $Cryptochrome1$, and arylalkylamine $N$-acetyltransferase-2 in olive flounder, $Paralichthys$ $olivaceus$

  • Kim, Na-Na;Shin, Hyun-Suk;Lee, Je-Hee;Choi, Cheol-Young
    • Animal cells and systems
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    • 제16권1호
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    • pp.27-33
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    • 2012
  • The suprachiasmatic nucleus (SCN) of the teleost hypothalamus contains a central circadian pacemaker, which adjusts circadian rhythms within the body to environmental light-dark cycles. It has been shown that exposure to darkness during the day causes phase shifts in circadian rhythms. In this study, we examined the effect of exposure to darkness on the mRNA expression levels of two circadian clock genes, namely, $Period2$ ($Per2$) and $Cryptochrome1$ ($Cry1$), and the rate-limiting enzyme in melatonin synthesis, arylalkylamine $N$-acetyltransferase-2 (Aanat2), in the pineal gland of olive flounder, $Paralichthys$ $olivaceus$. The expression of these genes showed circadian variations and was significantly higher during the dark phase. These changes may be involved in the mechanism of dark-induced phase shifts. Furthermore, this study suggests that olive flounder may be a teleost model to investigate the localization and function of circadian oscillators.

하악 과두 과형성증에 관한 방사선학적 연구 (A DIOGRAPHIC STUDY OF THE CONDYLAR HYPERPLASIA)

  • 김진수;김영진;최의환;김재덕
    • 치과방사선
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    • 제25권2호
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    • pp.569-578
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    • 1995
  • Condylar hyperplasia is a self-limiting condition characterized by a slowly progressing, enlargement of the mandible that results in facial asymmetry and a crossbite malocclusion. The facial asymmetry, open bite or crossbite, and radiographic evidence of an enlarged condyle confirm the diagnosis of condylar hyperplasia. The etiology of the condition is unknown. This condition usually first becomes apparent during the second decade of life, when one condyle continues to grow while the other is no longer active. Radiographically, the condyle may appear enlarged or the neck of the condyle maybe elongated or both may occur, Sometimes, however, no radiographically demonstrable condylar abnormality will be noted. Surgical correction with subcondylar osteotomy is the treatment of choice. We have observed two cases of condylar hyperplasia occurred in the left mandibular condyle of 24-year-old and 35-year-old women. We obtained that two cases were shown the followed results; 1. Clinically, both cases was unilaterally developed on C/C area, with temporomandibular disorders and pain, facial asymetry and malocclusion. 2. Radiographically, hyperplastic mass confined to the condyle. 3. Histopathologically, these cases shown increased hypertrophic region in parts, and lamellated bone with irregular trabeculae.

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Initial Reaction of Hexachlorodisilane on Amorphous Silica Surface for Atomic Layer Deposition Using Density Functional Theory

  • Kim, Ki-Young;Yang, Jin-Hoon;Shin, Dong-Gung;Kim, Yeong-Cheol
    • 한국세라믹학회지
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    • 제54권5호
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    • pp.443-447
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    • 2017
  • The initial reaction of hexachlorodisilane ($Si_2Cl_6$, HCDS) on amorphous silica ($SiO_2$) surface for atomic layer deposition was investigated using density functional theory. Two representative reaction sites on the amorphous $SiO_2$ surface for HCDS reaction, a surface hydroxyl and a two-membered ring, were considered. The reaction energy barrier for HCDS on both sites was higher than its adsorption energy, indicating that it would desorb from the surface rather than react with the surface. At high temperature range, some HCDSs can have kinetic energy high enough to overcome the reaction energy barrier. The HCDS reaction on top of the reacted HCDS was investigated to confirm its self-limiting characteristics.

여자 청소년의 비뇨생식기 관련 개인위생과 월경기 위생 관리 (Personal Hygiene Practices related to Genito-urinary Tract and Menstrual Hygiene Management in Female Adolescents)

  • 안숙희;조경미
    • 여성건강간호학회지
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    • 제20권3호
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    • pp.215-224
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    • 2014
  • Purpose: The study was to survey personal hygiene practice related to genito-urinary tract and menstrual hygiene management in female adolescents in order to obtain basic information for health education. Methods: With a descriptive survey design, 389 adolescents were recruited via convenience sampling in Korea. Survey instrument was the feminine and menstrual hygiene practice and perception of vaginal douching. Data were collected from a self-administered structured questionnaire. Results: Mean age of adolescents was 16.09 and menarche was at 13.21. While washing hands after urination/defecation was highly performed, wipe front to back and wash with soap and water were reported as being not well done. Twenty-eight percent reported douching habit. More positive beliefs about douching were reported by adolescents who practiced douching. Menstrual hygiene management was very appropriate with changing sanitary pads regularly with hand washing; but less performed for limiting bathing activity during menstrual periods and washing hands after activity of genito-urinary area. Conclusion: Some adolescents practiced inadequate hygiene practices especially for body cleansing during menstrual period and vaginal douching. It is important to develop and implement school health education programs on feminine and personal hygiene for adolescents to help them perform adequate health behaviors.

Preparation of melamine-grafted graphene oxide and evaluation of its efficacy as a flame retardant additive for polypropylene

  • Monji, Parisa;Jahanmardi, Reza;Mehranpour, Milad
    • Carbon letters
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    • 제27권
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    • pp.81-89
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    • 2018
  • The present study aimed to prepare a novel efficient flame retardant additive for polypropylene. The new flame retardant was prepared by chemical grafting of melamine to graphene oxide with the aid of thionyl chloride. Fourier-transform infrared spectroscopy and thermogravimetric analysis proved that melamine had been successfully grafted to the graphene oxide. The modified graphene oxide was incorporated into polypropylene via solution mixing followed by anti-solvent precipitatio. Homogeneous distribution as well as exfoliation of the nanoplatelets in the polymer matrix was observed using transmission electron microscopy. Thermogravimetric analysis showed a significant improvement in the thermo-oxidative stability of the polymer after incorporating 2 wt% of the modified graphene oxide. The modified graphene oxide also enhanced the limiting oxygen index of the polymer. However, the amount of improvement was not enough for the polymer to be ranked as a self-extinguishing material. Cone calorimetry showed that incorporating 2 wt% of the modified graphene oxide lowered total heat release and the average production rate of carbon monoxide during burning of the polymer by as much as 40 and 35%, respectively. Hence, it was concluded that the new flame retardant can retard burning of the polymer efficiently and profoundly reduce suffocation risk of exposure to burning polymer byproducts.

Time Pressure, Time Autonomy, and Sickness Absenteeism in Hospital Employees: A Longitudinal Study on Organizational Absenteeism Records

  • Kottwitz, Maria U.;Schade, Volker;Burger, Christian;Radlinger, Lorenz;Elfering, Achim
    • Safety and Health at Work
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    • 제9권1호
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    • pp.109-114
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    • 2018
  • Background: Although work absenteeism is in the focus of occupational health, longitudinal studies on organizational absenteeism records in hospital work are lacking. This longitudinal study tests time pressure and lack of time autonomy to be related to higher sickness absenteeism. Methods: Data was collected for 180 employees (45% nurses) of a Swiss hospital at baseline and at follow-up after 1 year. Absent times (hours per month) were received from the human resources department of the hospital. One-year follow-up of organizational absenteeism records were regressed on self-reported job satisfaction, time pressure, and time autonomy (i.e., control) at baseline. Results: A multivariate regression showed significant prediction of absenteeism by time pressure at baseline and time autonomy, indicating that a stress process is involved in some sickness absenteeism behavior. Job satisfaction and the interaction of time pressure and time autonomy did not predict sickness absenteeism. Conclusion: Results confirmed time pressure and time autonomy as limiting factors in healthcare and a key target in work redesign.