• Title/Summary/Keyword: wetA

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A Numerical Study on the Performance Analysis of the Plume Abatement NWD Cooling Tower (백연 방지를 위한 NWD냉각탑의 성능해석에 관한 수치해석적 연구)

  • 최창혁;최영기;소헌영
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.13 no.11
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    • pp.1049-1058
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    • 2001
  • The performance and design analysis for a NWD cooling tower using a combined wet and dry type fill are numerically investigated and compared with the experimental results. The Stoecker's method is applied to the wet section and LMTD or NTU-Effectiveness method to the wet and dry sections. The efficiency ratio of the NWD cooling tower to a wet type crossflow cooling tower is 59.34%. The predicted result shows a good agreement with the experimental data within 1.4% error. Plume abatement is far better with a NWD cooling tower than a counterflow cooling tower. It costs less than a conventional wet/dry tower because the finned exchanger is eliminated. This method also leaves out complexity in structure and Intricacy in operation.

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Genetic Control of Asexual Sporulation in Fusarium graminearum

  • Son, Hokyoung;Kim, Myung-Gu;Chae, Suhn-Kee;Lee, Yin-Won
    • 한국균학회소식:학술대회논문집
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    • 2014.10a
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    • pp.15-15
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    • 2014
  • Fusarium graminearum (teleomorph Gibberella zeae) is an important plant pathogen that causes head blight of major cereal crops such as wheat, barley, and rice, as well as causing ear and stalk rot on maize worldwide. Plant diseases caused by this fungus lead to severe yield losses and accumulation of harmful mycotoxins in infected cereals [1]. Fungi utilize spore production as a mean to rapidly avoid unfavorable environmental conditions and to amplify their population. Spores are produced sexually and asexually and their production is precisely controlled. Upstream developmental activators consist of fluffy genes have been known to orchestrate early induction of condiogenesis in a model filamentous fungus Aspergillus nidulans. To understand the molecular mechanisms underlying conidiogenesis in F. graminearum, we characterized functions of the F. graminearum fluffy gene homologs [2]. We found that FlbD is conserved regulatory function for conidiogenesis in both A. nidulans and F. graminearum among five fluffy gene homologs. flbD deletion abolished conidia and perithecia production, suggesting that FlbD have global roles in hyphal differentiation processes in F. graminearum. We further identified and functionally characterized the ortholog of AbaA, which is involved in differentiation from vegetative hyphae to conidia and known to be absent in F. graminearum [3]. Deletion of abaA did not affect vegetative growth, sexual development, or virulence, but conidium production was completely abolished and thin hyphae grew from abnormally shaped phialides in abaA deletion mutants. Overexpression of abaA resulted in pleiotropic defects such as impaired sexual and asexual development, retarded conidium germination, and reduced trichothecene production. AbaA localized to the nuclei of phialides and terminal cells of mature conidia. Successful interspecies complementation using A. nidulans AbaA and the conserved AbaA-WetA pathway demonstrated that the molecular mechanisms responsible for AbaA activity are conserved in F. graminearum as they are in A. nidulans. F. graminearum ortholog of Aspergillus nidulans wetA has been shown to be involved in conidiogenesis and conidium maturation [4]. Deletion of F. graminearum wetA did not alter mycelial growth, sexual development, or virulence, but the wetA deletion mutants produced longer conidia with fewer septa, and the conidia were sensitive to acute stresses, such as oxidative stress and heat stress. Furthermore, the survival rate of aged conidia from the F. graminearum wetA deletion mutants was reduced. The wetA deletion resulted in vigorous generation of single-celled conidia through autophagy-dependent microcycle conidiation, indicating that WetA functions to maintain conidia dormancy by suppressing microcycle conidiation in F. graminearum. In A. nidulans, FlbB physically interacts with FlbD and FlbE, and the resulting FlbB/FlbE and FlbB/FlbD complexes induce the expression of flbD and brlA, respectively. BrlA is an activator of the AbaA-WetA pathway. AbaA and WetA are required for phialide formation and conidia maturation, respectively [5]. In F. graminearum, the AbaA-WetA pathway is similar to that of A. nidulans, except a brlA ortholog does not exist. Amongst the fluffy genes, only fgflbD has a conserved role for regulation of the AbaA-WetA pathway.

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Wet Cupping (al-hijama) for Mental Health: A Systematic Review

  • Ucun, Yasemin
    • Journal of Acupuncture Research
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    • v.39 no.2
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    • pp.89-95
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    • 2022
  • This systematic review aimed to evaluate the effects of wet cupping on the treatment of mental illness. A total of 2,670 studies were retrieved using PubMed, Cochrane Library, Web of Science, Google Scholar, and Science Direct databases, and of these, 2,661 were excluded due to not meeting the inclusion criteria. There were 9 articles included in this review including 1,124 individuals who received wet cupping. Mental health was explored in, those who had migraines, metabolic syndrome, smoking addiction, post-traumatic stress, chronic medical disease, and depression. As an intervention procedure, the triple S technique was used in all studies. Only 3 studies reported that none of the participants complained of adverse events during or after the cupping therapy. In all studies, wet cupping was reported to be effective in reducing psychological symptoms. However, there are few randomized controlled trials testing the e?ectiveness of wet cupping in the treatment of mental health, and most are of poor quality. Therefore, more rigorous studies are required before the effectiveness of wet cupping for the treatment of mental illness can be determined.

Correlation Analysis between the Rheology Parameters of Concrete and the Rheological Parameters of Wet Sieving Mortar (콘크리트 레올로지 정수와 Wet Sieving 모르타르 레올로지 정수의 상관관계 분석)

  • Kim, In-Tae;Lee, Yu-Jeong;Han, Dong-Yeop
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2023.05a
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    • pp.103-104
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    • 2023
  • In this study, the correlation between the rheolog y parameter of fresh concrete and the rheology parameter of wet sieving mortar was analyzed for analyzing to possibility predicting the rheology parameter of fresh concrete. Through the experiment, the dynamic yield stress and plastic viscosity of concrete and wet sieving mortar show a direct proportional relationship, and the two data had a correlation. Therefore, it is thought that it is possible to predict the rheology parameter of fresh concrete through the rheology parameter of wet sieving mortar. However, in order to more accurately predict the rheology parameter of fresh concrete, it is need additional relationship analysis by collecting more rheology parameter data of fresh concrete and wet sieving mortar.

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Representation of Curl Exaggeration, Cohesion, Adhesion and Stiffness in Wet Curly Hair

  • Jong-Hyun Kim
    • Journal of the Korea Society of Computer and Information
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    • v.28 no.10
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    • pp.77-84
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    • 2023
  • Simulating the cohesion and stiffness of wet hair or fur in physics-based simulations is one of the most challenging problems. Wet hair or fur is characterized by bunching and stiffening at the ends, a phenomenon that can be seen in wet animal fur or hair. In addition, when wet hair interacts with a solid, adhesion occurs, but this problem becomes difficult to solve due to the different distribution and balance of forces in curly hair. In traditional methods, wet hair is represented by hand or by using static hairstyles to represent wet curls and hair. However, how to depict the details of wet curly hair has not been actively researched. In this paper, we propose a new algorithm to efficiently model the curl exaggeration, cohesion, adhesion, and stiffness of wet curly hair. The proposed method efficiently simulates cohesion and integrates stiffness constraints with curl dynamics to reliably control hair elasticity.

Analysis of wet Wire Drawing Process and Pass Redesign to Reduce Wire Breakage (습식 신선공정 해석 및 단선율 저감을 위한 패스 재설계)

  • 이상곤;김민안;김병민
    • Proceedings of the Korean Society of Precision Engineering Conference
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    • 2002.05a
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    • pp.1034-1037
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    • 2002
  • Wet wire drawing process is used to produce fine wire in the industrial field. The production of fine eire by using wet wire drawing process with appropriate dies pass schedule would be impossible without understanding of relationship between process parameters such as material properties, dies reduction, friction conditions, drawing speed etc. However, up to new, dies pass schedule of wet wire drawing process has performed by trial and error of expert. Therefore, this study investigates the relationship between process parameters quantitatively and analyzes a conventional wet wire drawing process. Using the results, the conventional pass schedule can be redesigned to reduce the wire breakage during wet wire drawing. To verily the result of this study, the wet wire drawing experiment was performed. And the results between conventional process and redesigned pass schedule were compared. As the comparison of results, the wire breakage was considerably reduced in the redesigned pass schedule more than conventional pass schedule.

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Study on Cooling Rates and Mechanical Properties of H.T. Steel Plates in the Underwater Wet arc welding (고장력강의 습식 수중 아크용접에 대한 냉각율과 기계적 특성에 관한 연구)

  • 김민남
    • Journal of Ocean Engineering and Technology
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    • v.2 no.1
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    • pp.125-134
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    • 1988
  • The feasibility for improving the cooling rates and mechanical properties of wet welding process is experimentally investigated by using new developed underwater wet electrodes and H.T. steel plates. Main results of this experimental study can be summarized as follows; 1) By shielding around weld arc surrounding, the cooling rates resulting from wet welds with developed electrodes on TMCP steel plates can be lower than of non-shielded wet welds. 2)A high quality of mechanical properties of wet welds on TMCP steel plates can be obtained with shielded weld arc surrounding.

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WET END MANAGEMENT BASED ON ON-LINE MEASUREMENTS AND CONTROL SOLUTIONS

  • Timo Rantala;Martti Artama;Jukka Nokelainen;Taina Sopenlehto
    • Proceedings of the Korea Technical Association of the Pulp and Paper Industry Conference
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    • 1999.11b
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    • pp.130-139
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    • 1999
  • In order to manage the wet end chemistry on paper machines, our goal is to control sub-processes through which we can influence the entire wet end operations with maximum effect. The most important sub-processes are: consistency, ash, and chemistry. The management of these three main groups is based on on-line maesurements and automatic control. This paper presents a new wet end management platform, a new analyzer. This new analyzer utilizes a modular structure and modem software. It is part of a new paper machine concept. The controls of this concept are feedback and feedforward solutions that control retention, consistencies, ash, and charge, resulting in a more stable wet end (30...80%), more uniform paper, and better rnnability.

A Study on the Improvement of Operation Performance of Wet Bell Diving System in the Salvage Ship (구조함정 Wet Bell Diving System 운용성능 개선에 관한 연구)

  • Choi, Woo-Suk;Chang, Ho-Seong
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.21 no.7
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    • pp.176-183
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    • 2020
  • A ship has three types of diving systems (Diver Stage Diving, Wet Bell Diving and Scuba Diving) to carry out a search-and-rescue operation. To reduce the possibility of decompression sickness, any diving systems shall comply with the decompression procedure according to the decompression table corresponding to the diving depth and diving time. The decompression procedure is largely divided into two methods: underwater decompression and underwater-onboard decompression. In particular, the surface interval shall not exceed 5 minutes, which is the phase from underwater decompression to underwater-onboard decompression, in accordance with the U.S Navy Diving Manual. However, the surface interval is greater than 5 minutes as a result of using Wet Bell Diving. This paper describes the result of cause analysis and measurement with improved Wet Bell Diving. Using improved Wet Bell Diving reduced the surface interval to less than 5 minutes. The result of the research can be used for operation and improving the performance of diving systems.

Evaluation of Particle Collection Efficiency in a Wet Electrostatic Precipitator Using an Electrosprayed Discharge Electrode (정전분무 방전극을 이용한 습식 전기집진장치의 미세먼지 집진효율 평가)

  • Kim, Hong-Jik;Kim, Jong-Hyeon;Kim, Jong-Ho
    • Journal of Korean Society for Atmospheric Environment
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    • v.31 no.6
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    • pp.530-537
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    • 2015
  • The wet electrostatic precipitator (wet ESP) is an effective control device which removes submicron particles reentrained in a collection plate and water soluble gas. However, its collection efficiency decreases, as its operation is subject to water-induced distortion of the collection electrode. In order to make up for the limitation, we modified the wet ESP system by installing electrosprayed discharge electrodes. The modified wet ESP system can wash both the collection plate and discharge electrode. As a result, we were able to fabricate a compact wet ESP with a small specific collecting area ($0.18m^2(m^3/min)$) that can accomplish a high collection efficiency of fine particles (97.1%). In addition, the device obtained a relatively low specific corona power of approximately $10W/(m^3/min)$.