• Title/Summary/Keyword: 청소

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Characteristics of heavy metal concentrations in urban stormwater runoff, Daejeon, Korea (도시 유역 강우유출수 내 중금속 농도의 변화 특성에 관한 연구)

  • Yu, Eunjin;Seo, Dongil
    • Journal of Korea Water Resources Association
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    • v.51 no.10
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    • pp.917-927
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    • 2018
  • Seven heavy metal concentrations (As, Cd, Cr, Cu, Ni, Pb, Zn) were continuously analyzed for twenty rainfall events in 2017~2018 in an urban basin. The overall and dynamic correlations between runoff characteristics and heavy metal concentrations were examined. The peak metal concentration generally appeared in the initial runoff but found to be delayed when the rainfall intensity was low. The rainfall duration had no relationship with either heavy metal concentrations or their total mass. Dynamics of heavy metal mass (load), with the exception of Cu and Zn, showed strong correlation with the 30 minute rainfall intensity (0.60~0.88) and runoff volume (0.74~0.89). While event mean concentration (EMC) showed positive correlation (0.54~0.73) with antecedent dry days (ADD), no significant relationship was found between runoff volume and pollutant concentration. This implies that the pollutants built up on the surface during dry days are washed off even with low rainfall energy. The dynamics of heavy metal and TSS concentrations showed good correlation (0.68~0.87). This result shows that the metals are transported along with solid particles as adsorbate in surface runoff. Regular street sweeping will reduce significant amount of heavy metal loads in urban surface runoff.

Optimal Nozzle Design of Bladeless Fan Using Design of Experiments (실험계획법을 이용한 날개 없는 선풍기의 노즐 형상 최적 설계)

  • Jeong, Siyoung;Lee, Jongsoo;Yoon, Jaehyun
    • Transactions of the Korean Society of Mechanical Engineers A
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    • v.41 no.8
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    • pp.711-719
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    • 2017
  • Bladeless fan is becoming increasingly popular owing to its advantages, such as improved safety, easy to clean, and attractive shape. However, many people are reluctant to purchase it because of several disadvantages, such as noise and moderate wind; therefore, research on how improve wind generation without increasing the motor speed is required. This study investigates the optimization of the shape of the nozzle and nearby surface using CFD (Computational Fluid Dynamics) simulation, ANSYS fluent. The results are analyzed by ANOM (analysis of mean) and interaction analysis; therefore this study suggests the variables of affecting Coanda effect and satisfy the govern equation, the conservation of momentum. The optimal combination was found through a predictive equation. In this study, factors and levels that affect the mass flow rate were selected and experimental points were arranged using the orthogonal array table. The value of the mass flow rate was confirmed by ANSYS fluent, which is a CFD program. Through the ANOM, it was confirmed that the nozzle distance is the most influential parameter affecting the mass flow rate. Furthermore, the mass flow rate obtained from the predictive equation and the mass flow rate from the CFD correspond to the largest values. Results from this study confirmed that the mass flow rate is increased by a change in the shape, even if the motor speed did not increase.

Effect of Aotomatic Scale Removal System for Piping in Refrigeration & Air Conditioning System (냉동·공조기 배관내 스케일 자동제거장치의 효과)

  • Kim, Jong-Ryeol
    • Journal of the Korean Applied Science and Technology
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    • v.34 no.4
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    • pp.908-914
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    • 2017
  • In this study, we developed a system that automatically removes the scale in the piping by using electrolysis principle in order to solve the cooling performance of the refrigeration and air conditioning system by acting as heat resistance in the heat transfer process by forming the scale in the heat exchanger for refrigeration air conditioning. We want to check the performance through experiments. Therefore, by circulating the treated water using the principle of electrolysis without stopping the system, Ca, Mg and $SiO_2$ are precipitated in the form of solids and discharged to the outside of the pipe system, thereby preventing scale formation in the pipe and removing the scale. Thereby maintaining the heat transfer performance of the pipe. As a result of the experiment, the heat transfer rate of the scaled pipe was 86.66% when the heat transfer rate of the new pipe was 100, and the heat transfer rate was recovered to 90.5% when the scaled pipe was operated for 1 month. The heat transfer rate recovered to 97.86% when driving for two months and to 98.72% for three months. It was confirmed that the scaling effect of the scale formed in the piping was understood in a relatively short experiment period, and the heat transfer performance was also influenced.

Remote control system for management of a stall using PDA (PDA를 이용한 축사관리 원격제어 시스템)

  • Kim, Tae-Soo;Chun, Joong-Chang
    • Proceedings of the Korean Institute of Information and Commucation Sciences Conference
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    • 2009.10a
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    • pp.1010-1013
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    • 2009
  • The youths of the farming village have moved to the metropolis, thus the most of the manpower which engages to a production remained in the village reaches layer old age and all thing sprouts long the whole and it is one. So to remove the waste of barn rather than to give feed to the livestock is hard that what step all automation of this part is necessary. Consequently we have developed the automation system in order to reduce the massive death of the livestock at the time of intense cold and hot. The system will be able to clean the waste of the barn and confront quickly in the change of temperature which is sudden it came. And we proposed also the system that will be able to watch at real-time and monitor the operational environment from a remote using CCD camera. In this paper, we proposed the remote control system which uses PDA in order to control the automation system of a stall while moving. The proposed system was embodied in order for the control and the monitor while the user is mobile using PDA screens. We also added a protection system in that system. The system sends the case warning and SMS while will have the fire and the intrusion from the outside and prevents a robbery.

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Clinical Microscopy: Performance, Maintenance and Laser Safety (임상에서의 현미경: 작동, 유지보수 및 레이저 안전)

  • Lee, Tae Bok
    • Korean Journal of Clinical Laboratory Science
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    • v.51 no.2
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    • pp.125-133
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    • 2019
  • A microscope is the fundamental research and diagnostic apparatus for clinical investigation of signaling transduction, morphological changes and physiological tracking of cells and intact tissues from patients in the biomedical laboratory science. Proper use, care and maintenance of microscope with comprehensive understanding in mechanism are fully requested for reliable image data and accurate interpretation for diagnosis in the clinical laboratory. The standard operating procedure (SOP) for light microscopes includes performance procedure, brief information of all mechanical parts of microscopes with systematic troubleshooting mechanism depending on the laboratory capacity. Maintenance program encompasses cleaning objective, ocular lenses and inner optics; replacement and calibration of light source; XY sample stage management; point spread function (PSF) measurement for confocal laser scanning microscope (CLSM); quality control (QC) program in fluorescent microscopy; and systematic troubleshooting. Laser safety is one of the concern for medical technologists engaged in CLSM laboratory. Laser safety guideline based on the laser classification and risk level, and advisory lab wear for CLSM users are also expatiated in this overview. Since acquired image data presents a wide range of information at the moment of acquisition, well-maintained microscopes with proper microscopic maintenance program are impulsive for its interpretation and diagnosis in the clinical laboratory.

ADHD Trait, Emotional Music Use, and Expectation for Future Life in Early Adolescence: Focused on Mediating Effect of Relationship Initiation (초기 청소년기의 ADHD 성향과 정서적 음악사용 및 삶의 기대 간의 관계: 대인관계 형성의 매개효과를 중심으로)

  • Park, Alexander
    • The Journal of the Korea Contents Association
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    • v.21 no.6
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    • pp.629-638
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    • 2021
  • This study investigated the relationships between ADHD trait, emotional music use, relationship initiation, and expectation for future life in early adolescence, and to verify path model to predict the expectation for future life. The participants were 347 male and female middle school students, their average of ages was 13.35 (SD=.91). The ADHD trait was measured with self-report scale, emotional music use and relationship initiation were measured with sub-scales of Use of Music Inventory and Interpersonal Competence Questionnaire, and expectation for future life was measured with modified items of Satisfaction with Life Scale. Results revealed that ADHD trait was negatively correlated with relationship initiation and expectation for future life, whereas emotional music use was positively correlated with relationship initiation and expectation for future life. And, relationship initiation positively correlated with expectation for future life. The alternative model was adopted that included a direct path from ADHD trait to expectation for future life in the proposed model, rather than the proposed model in which ADHD trait and emotional music use affects expectation for future life through relationship initiation. The findings of this study should provide useful information for further studies and for professionals who try to promote the expectation for future life in early adolescence.

Two Types of Post-human in Recent Korean SF Films : Focusing on (2021), (2021) (최근 한국영화 속 포스트-휴먼의 두 가지 양상: <승리호>(2021), <서복>(2021)을 중심으로)

  • Yoo, Jae-eung;Lee, Hyun-Kyung
    • The Journal of the Convergence on Culture Technology
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    • v.8 no.1
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    • pp.379-384
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    • 2022
  • The year 2021 is a monumental year for the history of Korean cinema that inferiority of the sci-fi genre, by the appearance of two sci-fi blockbuster films- produced by Netflix and produced by TVing-at the same time. Coincidentally, both of movies are sci-fi films which appear post-human such as robot and clone. As can be seen in 『Frankenstein』 story, the progenitor of science fictions, the mankind have imagined beings similar to humen or post-human who are another human being for a long time. deals with the unusual subject matter of a space scavenger and a space janitor, and the main character is a robot that very familiar with human. is the story of a man who lives for a limited life protects and accompanies a clone named Seobok who was created as a test subject. This film deals with the philosophical themes like death and eternal life through the existential concerns of two characters. use Korean Shinpa -Korean specific senimental code-sentiment on narrative, and has the character of a road movie set in Korea's geographical space.

A comparative investigation of infection control perception and performance of occupational therapists before and after the outbreak of COVID-19 (COVID-19 발생 전후 작업치료사의 감염관리 인식 및 수행도 비교 조사)

  • Joo, HoYeon;Cha, Tae-Hyun
    • Journal of the Korea Convergence Society
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    • v.13 no.3
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    • pp.91-103
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    • 2022
  • This study surveyed 101 occupational therapists who were performing occupational therapy before and after the COVID-19 outbreak to compare their perceptions and performance of hand washing, use of personal protective equipment, and infection control of surrounding environment. Mann-Whitney U test, Kruskal wallis H test, Wilcoxon signed-rank test, Pearson's correlation coefficient were used analyzed. As a result, it was confirmed that they received better infection control education after the outbreak compared to before the outbreak of COVID-19, and their experience with infectious diseases was lower. In addition, it was found that the perception and performance of infection control in hand washing, personal protective equipment, and surrounding environment cleaning were improved after the outbreak compared to before the outbreak of COVID-19. However, to this day, hand washing for more than 40 seconds in running water recommended by the Korea Centers for Disease Control and Prevention, cleaning the treatment room, and disinfection of treatment tools are still in need of improvement. Through this study, infection control education should be repeated regularly to minimize the occurrence of infectious diseases, and It will be a basic data that can be used in infection control education and follow-up studies for occupational therapists in the future.

Exploring the Effects of Complex Body Habits Training on Autistic Youth (복합적 몸 습관훈련이 자폐 청년들에게 미치는 효과 탐색)

  • Lee, Ku Yeon;Lee, Hyung H.
    • Journal of Naturopathy
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    • v.9 no.2
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    • pp.62-70
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    • 2020
  • Purpose: According to the Body-EU education program, this study investigates changes after conducting education with ten subjects with autism symptoms (disability level 2~3) 63 times (126 hours) for nearly two years. Methods: Body-EU habit practice, note writings discussion, singing, Bible study, question and communication, class arrangement, etc., a total of 63 times were educated for 2 hours each week. Results: Subjects felt comfortable breathing and improved energy. Other subject's habit of an out-toed gait step and bending back alleviated. One subject made it easier to speak, so if talking with no strength. When breathing, the stuffy nose improved, the eyes became calm, and the hands and feet were warm. Subject felt like my head was cleaned. Heart tightness disappeared. Subject felt at ease as gaining confidence. The subject gained confidence in seeing whoever the other person was. The subject's pronunciation became more sophisticated, with more confidence, and his mouth cramping alleviated. Subjects with right eye movements showed a relatively high concentration in education time. Conclusions: Subjects are educated and trained in making general habits of their body from morning to going to bed. This study was a research program for ordinary people, but it confirmed with autism. Whether it was genetic autism or acquired autism, they could be somewhat relieved.

A Study on the Institutional Limitations of Chemical Exposure Control for Cleaning Workers - Focusing on the Exclusion of Preparation and Submission of Material Safety Data Sheets (청소노동자 화학물질 노출 관리의 제도적 한계 고찰 - 물질안전보건자료 작성·제출 제외 조항을 중심으로)

  • Shin, Saemi;Ki, Nosung;Lee, Hea Min;Kim, Dong Hyeon;Wee, Seohyeon;Byeon, Sang-Hoon
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • v.32 no.1
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    • pp.41-52
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    • 2022
  • Objectives: This study intends to review the impact on cleaning workers and suggest directions for improvement by reviewing the legal and institutional ways in which Article 86 Nos. 7 and 16 of the Enforcement Decree of the Occupational Safety and Health Act work on the maintenance and promotion of cleaning workers' health. Methods: The following laws and systems were reviewed and considered: First, the occupational safety and health legislation obligated or required to be applied to protect the health of cleaning workers; Second, the status of control of chemicals or mixtures used at cleaning sites through the Consumer Chemicals Product and Biocide Safety Control Act; Third, Control of consumer products according to foreign material safety data sheet related laws. Results: Legal and institutional measures necessary to protect the health of cleaning workers include the legal control of harmful substances to be controlled, work environment monitoring, and special health examinations. The application of the Consumer Chemicals Product and Biocide Safety Control Act does not satisfy the legal and practical level of health maintenance and promotion required by the Occupational Safety and Health Act, and the communication of chemical information is insufficient. Overseas, there are restrictions on the use of consumer products in the workplace without material safety data sheets. Conclusions: It is necessary to improve the system to ensure the health of workers handling consumer chemical products. The remaining laws and regulations exempted from the obligation to prepare material safety data sheets should be additionally reviewed.