• Title/Summary/Keyword: heat combination

Search Result 686, Processing Time 0.027 seconds

An Experimental Study on the Application of Horizontal Barrier and In-Rack Sprinklers to Prevent Vertical Spread of Rack-type Warehouse Fires (랙크식 창고 화재의 수직 확산 방지를 위한 수평차단막과 In-Rack 스프링클러 적용에 관한 실험연구)

  • Park, Moon-Woo;Hong, Sung-Ho;Choi, Ki-Ok;Choi, Don-Mook;Kim, Soo-Jin
    • Journal of the Korean Society of Safety
    • /
    • v.34 no.5
    • /
    • pp.15-21
    • /
    • 2019
  • A rack-type warehouse has the advantage of storing a large amount in a small area by loading goods vertically. But in terms of fire risk, the fire load is very high, which can cause massive damage in the event of a fire. In the United States, research has been actively conducted to minimize the spread of vertical fires, and relevant standards have been established and operated. In Korea, research and related standards are insufficient to prevent the vertical spread of rack-type warehouse fires. In this study, an experimental study was conducted to prevent the vertical spread of a rack-type warehouse fire using a horizontal barrier and in-rack sprinklers. As a result of the test, the horizontal barrier considering the continuous flame prevented the vertical spread of the flame for a certain time. However, the horizontal barrier with continuous flame did not show the effect of preventing continuous flame. The combination of the horizontal barrier and the in-rack sprinkler prevented the vertical spread of fire effectively. In addition, the heat collecting effect through the horizontal barrier was shown and helped the early operation of the in-rack sprinklers.

Recent Domestic and International Trends in Clinical Research of Herbal Medicine Treatment for Crohn's disease (크론병의 한약 치료에 대한 최근 국내외 임상연구 동향)

  • Lee, Shin Hee;Heo, Yu Jin;Cho, Yun Soo
    • The Journal of Pediatrics of Korean Medicine
    • /
    • v.35 no.4
    • /
    • pp.56-74
    • /
    • 2021
  • Objectives The purpose of this study is to analyze the trend of herbal medicine treatment, treatment's effect and stability for Crohn's disease by reviewing clinical studies published over the past 5 years. Methods 22 articles which were published from 2017 to August, 2021 were obtained from the ScienceON, Research information sharing service (RISS), Koreanstudies Information Service System (KISS), Oriental medicine advanced searching integrated system (OASIS), China national knowledge infrastructure (CNKI), Pubmed. We analyzed the literature in regards to the treatment methods and results. Results There were 6 case reports, 1 controlled clinical trial, and 15 randomized controlled trial and in most cases, herbal medicines and Western medicines were administered in combination. The pathology of damp-heat due to spleen deficiency was the most common, and Sijunzi-tang and Shenling Baishu san were the most commonly used. As a result of the treatment, it was found that the combined administration of the herbal medicine and the Western medicine was more effective than the administration of the Western medicine alone. Conclusions Herbal treatment of Crohn's disease induced high cure rate safely than when only western treatment was applied. Future studies on safety and studies that can suggest specific guidelines for the combined administration of western and herbal medicines are needed.

Sensitivity Analysis of Near Surface Air Temperature to Land Cover Change and Urban Parameterization Scheme Using Unified Model (통합모델을 이용한 토지피복변화와 도시 모수화 방안에 따른 지상 기온 모의성능 민감도 분석)

  • Hong, Seon-Ok;Byon, Jae-Young;Park, HyangSuk;Lee, Young-Gon;Kim, Baek-Jo;Ha, Jong-Chul
    • Atmosphere
    • /
    • v.28 no.4
    • /
    • pp.427-441
    • /
    • 2018
  • This study examines the impact of the urban parameterization scheme and the land cover change on simulated near surface temperature using Unified Model (UM) over the Seoul metropolitan area. We perform four simulations by varying the land cover and the urban parameterization scheme, and then compare the model results with 46 AWS observation data from 2 to 9 August 2016. Four simulations were performed with different combination of two urban parameterization schemes and two land cover data. Two schemes are Best scheme and MORUSES (Met Office Reading Urban Surface Exchange Scheme) and two land cover data are IGBP (International Geosphere and Biosphere Programme) and EGIS (Environmental Geographic information service) land cover data. When land use data change from IGBP to EGIS, urban ratio over the study area increased by 15.9%. The results of the study showed that the higher change in urban fraction between IGBP and EGIS, the higher the improvement in temperature performance, and the higher the urban fraction, the higher the effect of improving temperature performance of the urban parameterization scheme. 1.5-m temperature increased rapidly during the early morning due to increase of sensible heat flux in EXP2 compared to CTL. The MORUSES with EGIS (EXP3) provided best agreement with observations and represents a reasonable option for simulating the near surface temperature of urban area.

Treatment of Cinnamomi Cortex combined with hyperthermia synergistically suppressed proliferation and induced apoptosis in U937 cell line. (U937 세포에서 육계와 온열 병행 치료가 세포증식 억제와 세포사멸 유도에 미치는 연구)

  • Ahn, Chae Ryeong;Park, Sun-Hyang;Kim, Hong Jun;Jeong, Jeong Min;Baek, Seung Ho
    • Herbal Formula Science
    • /
    • v.27 no.1
    • /
    • pp.45-52
    • /
    • 2019
  • Objectives : Hyperthermia is a widely used therapeutic tool for cancer therapy and a well-known inducer of apoptosis. Although the Cinnamomi cortex (CC) is a potent anticancer agent for several human carcinomas, it is less potent in the human U937 cell line. To explore any enhancing effects of CC with hyperthermia induced apoptosis, this study investigated the combined effects and apoptotic mechanisms of hyperthermia and CC in U937 cells. Methods : U937 cells were heat treated at $43^{\circ}C$ for 30 min with or without pre-treatment for 1h with CC and then incubated at $37^{\circ}C$ with 5% $CO_2$. Cell viability was analyzed by MTT assay and Trypan blue assay. Morphological changes reflecting apoptosis were visualized under microscope. Synergy effect of CC combined with hyperthermia were calculated by Compusyn software. The expression of proteins related to apoptosis and signaling pathways was determined by western blotting. Results : Hyperthermia with CC reduced cell viability and induced apoptosis. Combined hyperthermia and CC treatment markedly augmented apoptosis by upregulating proapoptotic proteins and suppressing antiapoptotic proteins, culminating in caspase-3 activation. Furthermore, the combined treatment, decreased the expression of in Bcl-2 family, cyclin D1, VEGF, MMP2 and MMP9 expression. Conclusion : This study provides compelling evidence that hyperthermia, in combination with CC, is a promising therapeutic strategy for enhancement of apoptosis and suggests a promising therapeutic approach for cancer.

Microstructure and High Temperature Mechanical Properties of Oxide Dispersion Strengthened Steels Manufactured by Combination Milling Process (복합 밀링 공정으로 제조된 산화물 분산 강화 강의 미세조직 및 고온 기계적 특성)

  • Lee, Jung-Uk;Kim, Young-Kyun;Kim, Jeoung Han;Kim, Hwi-Jin;Lee, Kee-Ahn
    • Journal of Powder Materials
    • /
    • v.28 no.5
    • /
    • pp.389-395
    • /
    • 2021
  • Oxide dispersion-strengthened (ODS) steel has excellent high-temperature properties, corrosion resistance, and oxidation resistance, and is expected to be applicable in various fields. Recently, various studies on mechanical alloying (MA) have been conducted for the dispersion of oxide particles in ODS steel with a high number density. In this study, ODS steel is manufactured by introducing a complex milling process in which planetary ball milling, cryogenic ball milling, and drum ball milling are sequentially performed, and the microstructure and high-temperature mechanical properties of the ODS steel are investigated. The microstructure observation revealed that the structure is stretched in the extrusion direction, even after the heat treatment. In addition, transmission electron microscopy (TEM) analysis confirmed the presence of oxide particles in the range of 5 to 10 nm. As a result of the room-temperature and high-temperature compression tests, the yield strengths were measured as 1430, 1388, 418, and 163 MPa at 25, 500, 700, and 900℃, respectively. Based on these results, the correlation between the microstructure and mechanical properties of ODS steel manufactured using the composite milling process is also discussed.

Durability Evaluation of High-Performance, Low-Heat Self-Compacting Concrete for Foundation of Tall Buildings (초고층 건축물 매트 기초용 고성능 콘크리트 내구성 평가)

  • Kim, Young-Bong;Park, Dong-Cheon
    • Journal of the Korea Institute of Building Construction
    • /
    • v.22 no.5
    • /
    • pp.425-430
    • /
    • 2022
  • Concrete used for the foundation of high-rise buildings is often placed through in an integrated pouring to ensure construction efficiency and quality. However, if concrete is placed integrally, there is a high risk of temperature cracking during the hydration reaction, and it is necessary to determine the optimal mixing design of high-performance, high-durable concrete through the replacement of the admixture. In this study, experiments on salt damage, carbonation, and sulfate were conducted on the specimen manufactured from the optimal high-performance low-heating concrete combination determined in the author's previous study. The resistance of the cement matrix to chlorine ion diffusion coefficient, carbonation coefficient, and sulfate was quantitatively evaluated. In the terms of compression strength, it was measured as 141% compared to the structural design standard of KCI at 91 days. Excellent durability was expressed in carbonation and chlorine ion diffusivity performance evaluation. In particular, the chlorine ion diffusion coefficient, which should be considered the most strictly in the marine environment, was measured at a value of 4.09×E-12m2/y(1.2898×E-10m2/s), and is expected to be used as a material property value in salt damage durability analysis. These results confirmed that the latent hydroponics were due to mixing of the admixture and high resistance was due to the pozzolane reaction.

Analysis of Meteorological Characteristics by Fine Dust Classification on the Korean Peninsula, 2015~2021 (2015년~2021년 한반도 고농도 미세먼지 사례의 유형분류에 따른 기상학적 특징 분석)

  • Jee, Joon-Bum;Cho, Chang-Rae;Kim, Yoo-Jun;Park, Seung-Shik
    • Atmosphere
    • /
    • v.32 no.2
    • /
    • pp.119-133
    • /
    • 2022
  • From 2015 to 2021, high-concentration fine dust episodes with a daily average PM2.5 concentration of 50 ㎍ m-3 or higher were selected and classified into 3 types [long range transport (LRT), mixed (MIX) and Local emission and stagnant (LES)] using synoptic chart and backward trajectory analysis. And relationships between the fine particle data (PM2.5 and PM10 concentration and PM2.5/PM10 ratio) and meteorological data (PBLH, Ta, WS, U-wind, and Rainfall) were analyzed using hourly observation for the classification episodes on the Korean Peninsula and the Seoul metropolitan area (SMA). In LRT, relatively large particles such as dust are usually included, and in LES, fine particle is abundant. In the Korean peninsula, the rainfall was relatively increased centered on the middle and western coasts in MIX and LES. In the SMA, wind speed was rather strong in LRT and weak in LES. In LRT, rainfall was centered in Seoul, and in MIX and LES, rainfall appeared around Seoul. However, when the dust cases were excluded, the difference between the LRT and other types of air quality was decreased, but the meteorological variables (Ta, RH, Pa, PBLH, etc.) were further strengthened. In the case of the Korean Peninsula, it is difficult to find a clear relationship because regional influences (topographical elevation, cities and coasts, etc.) are complexly included in a rather wide area. In the SMA, it is analyzed that the effects of urbanization such as the urban heat island centered on Seoul coincide with the sea and land winds, resulting in a combination of high concentrations and meteorological phenomena.

A Review on the of External Ointment Treatment for Diabetic Foot Ulcer (당뇨병성 족부 궤양의 외용 연고 처치에 대한 고찰)

  • Jeong, Mi-rae;Heo, Eun-na;Kim, Chul-yun;Kwon, kang;Seo, Hyung-sik
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
    • /
    • v.35 no.3
    • /
    • pp.66-94
    • /
    • 2022
  • Objectives : Diabetic Foot Ulcer(DFU) is one of the common complications of diabetes. DFU is difficult to treat compared to other chronic wounds and clinically effective treatments are limited. The purpose of this study is to review the of external ointment treatment for DFU. Methods : 8 databases such as PubMed, EMBASE, CENTRAL, CNKI, NDSL, RISS, KISS, OASIS including English, Korean and Chinese were searched by structured search strategies that consist of terms as 'diabetic foot', 'diabetic foot ulcer(DFU)' and 'randomized' from January 2001 to January 2021. All randomized controlled trials(RCTs) involving treatment group as external ointment or in combination with conventional treatment were included. Results: A total of 20 RCTs was identified and analyzed. In treatment group, ointment was applied based on conventional treatment. A total of 16 different ointments were used, and the frequency of use was highest in the order of Heat-clearing drug, Blood-activating and stasis-dispelling drug, Tonifying and Replenishing drug and Orifice-opening drug. The most used herbs were in the order of Coptis chinensis Franch., Phellodendron chinense Schneid., Borneolum syntheticum., Angelica sinensis(Oliv.) Diels. In treatment group, a clinically effective effect was obtained compared to the contrast group. Conclusions : The result of this study suggest that external ointment treatment based on conventional treatment can be applied to DFU.

Estimation of water surface evaporation in Yongdam Dam using Empirical wind function (경험적 바람공식을 적용한 용담댐 내의 수면증발량 추정)

  • Minwoo Park;Sumiya Uranchimeg;Ho-Jun Kim;Min-kyu Jung;Hyun-Han Kwon
    • Proceedings of the Korea Water Resources Association Conference
    • /
    • 2023.05a
    • /
    • pp.291-291
    • /
    • 2023
  • 증발량을 산정하는 방법 중 증발접시를 활용한 방법은 하천의 증발량을 직접적으로 측정할 수 있는 장점이 있는 반면, 장기간의 증발접시를 활용한 증발량 추정은 현실적으로 쉽지 않다. 대표적인 증발량 산정식으로는 에너지 수지 및 공기동역학적 원리의 혼합적용 방법(PCE, Penman combination equation)과 경험적 바람공식(PWF, Penman wind function)이 있다. PCE로 산정된 증발량의 경우 하천 내 바닥열(bed heat flux)과 물기둥의 열저장 변화율이 장기간 규모의 순 복사량에 비해 작은 값을 가져 식에서 제외되므로 전반적으로 증발량이 과대 추정되는 문제가 발생한다. 반면, PWF로 산정한 증발량에서는 광범위한 매개변수 범위와 기상자료의 부족으로 모형의 불확실성을 증대시키는 요인으로 작용한다. 본 연구의 최종적인 목표는 하천 수로의 수면증발량을 추정하는 것이지만, 실제 하천 중심에서 증발량을 추정하기 위한 수문학적 자료는 매우 부족한 실정이다. 따라서, 본 연구에서는 유역단위에서의 증발량을 전이하는 방안을 모색하고자 하며, 구체적인 연구과정은 다음과 같다. 첫째, 유역단위 수문학적 자료를 수집하여(flux tower 자료 활용) 유역단위의 증발량을 산정한다. 둘째, PCE와 PWF으로 산정한 증발량과 관측된 증발량을 이용하여 각 식의 매개변수를 최적화한다. 마지막으로 최적화된 매개변수를 적용한 증발량과 관측값의 유사성을 분석한다. 본 연구에서는 하천단위의 증발량을 산정하기 위해 PWF을 적용하였으며 용담댐 내의 기상자료를 활용하여 산정한 증발량과 실제 용담댐 내의 수면증발량의 상관성을 분석한 결과 높은 상관성 확인할 수 있었다. 따라서 하천 주변에 증발량 추정을 위한 최소한의 기상정보가 존재하는 지역에서, 하천단위의 증발량을 산정할 수 있으며 장기간의 증발량도 산정할 수 있을 것으로 판단된다.

  • PDF

No more tears from surgical site infections in interventional pain management

  • Seungjin Lim;Yeong-Min Yoo;Kyung-Hoon Kim
    • The Korean Journal of Pain
    • /
    • v.36 no.1
    • /
    • pp.11-50
    • /
    • 2023
  • As the field of interventional pain management (IPM) grows, the risk of surgical site infections (SSIs) is increasing. SSI is defined as an infection of the incision or organ/space that occurs within one month after operation or three months after implantation. It is also common to find patients with suspected infection in an outpatient clinic. The most frequent IPM procedures are performed in the spine. Even though primary pyogenic spondylodiscitis via hematogenous spread is the most common type among spinal infections, secondary spinal infections from direct inoculation should be monitored after IPM procedures. Various preventive guidelines for SSI have been published. Cefazolin, followed by vancomycin, is the most commonly used surgical antibiotic prophylaxis in IPM. Diagnosis of SSI is confirmed by purulent discharge, isolation of causative organisms, pain/tenderness, swelling, redness, or heat, or diagnosis by a surgeon or attending physician. Inflammatory markers include traditional (C-reactive protein, erythrocyte sedimentation rate, and white blood cell count) and novel (procalcitonin, serum amyloid A, and presepsin) markers. Empirical antibiotic therapy is defined as the initial administration of antibiotics within at least 24 hours prior to the results of blood culture and antibiotic susceptibility testing. Definitive antibiotic therapy is initiated based on the above culture and testing. Combination antibiotic therapy for multidrug-resistant Gram-negative bacteria infections appears to be superior to monotherapy in mortality with the risk of increasing antibiotic resistance rates. The never-ending war between bacterial resistance and new antibiotics is continuing. This article reviews prevention, diagnosis, and treatment of infection in pain medicine.