• 제목/요약/키워드: Thermal sensation

검색결과 286건 처리시간 0.026초

녹지 조성 시나리오에 따른 도시 열환경 개선 효과 분석 (Scenario-Based Analysis on the Effects of Green Areas on the Improvement of Urban Thermal Environment)

  • 민진규;엄정희;성욱제;손정민;김주은
    • 한국조경학회지
    • /
    • 제50권6호
    • /
    • pp.1-14
    • /
    • 2022
  • 본 연구는 도시화 과정에서 발생한 도시 열섬현상을 완화하기 위해 도시 내에서 시행할 수 있는 생활권 녹지 조성 방법인 근린공원 조성, 소공원 조성, 주차장 녹화, 가로수 식재, 옥상·벽면 녹화 다섯 가지의 유형에 대해 세부 녹화 시나리오를 설정하여 열환경 개선 효과를 정량적으로 분석하는 것을 목표로 한다. 열환경 개선 효과를 확인하기 위해 미기후 시뮬레이션 프로그램인 ENVI-met 4.4.6v 모델을 활용하였다. 분석 결과, 공원의 식재 밀도가 높아질수록 기온이 낮아졌으나 사람이 느끼는 온열 체감 정도인 열쾌적성 지수 PET는 기온과 정비례하지 않았다. 수목이 증가하며 기온은 감소하였으나 상대습도가 소폭 증가 및 풍속이 다소 감소하였으며, 특히 PET에 많은 영향을 미치는 평균 복사온도가 수목 밀도와 정비례하지 않아 PET 역시 기온과 다른 양상을 보였다. 소공원은 한 개소 조성 후 효과를 확인하였을 때 최대 56m 반경까지 기온 저감 영향을 주었고, 250m 간격으로 세 개소를 추가 조성한 경우 기온 저감 범위가 약 12.5% 증가하였다. 기온과 달리 PET는 식재된 수목 영역 인근만 영향을 미쳐 소공원 조성 후 주변 환경의 열쾌적성은 큰 차이를 보이지 않았다. 지표면 포장을 아스팔트에서 잔디블록으로 변경하거나 옥상 및 벽면녹화 시행 등은 직접적인 일사 차양의 역할을 하지 않으나 기온 저감에 긍정적인 효과를 주었고, PET는 세 유형 모두 조성 전후 유의미한 차이를 보이지 않았다. 가로수는 식재 간격이 좁을수록 더 높은 기온 저감 효과를 보였으나, PET는 수목 밀도와 정비례하지 않았다. 가로수 하부 관목 식재의 경우 기온 저감에는 큰 영향을 주지 않으나 열쾌적성 개선에는 긍정적인 영향을 주었다. 본 연구는 도시 열섬현상 해소를 위한 생활권 녹지 조성 전략을 개괄적으로 제시하고 효율적인 열환경 개선을 위한 세부 전략을 수립하는 데에 활용될 수 있을 것으로 판단된다.

에어컨의 기류 및 온도 변동에 따른 인체 순응에 관한 연구 (Development of Thermal Comfort Sensation in the Variation of Air-velocity and Temperature in Air-conditioner)

  • 장문간;금종수;조관식;이기섭;최광환;정용현;김동규;김형철
    • 한국감성과학회:학술대회논문집
    • /
    • 한국감성과학회 2001년도 춘계학술대회 논문집
    • /
    • pp.141-146
    • /
    • 2001
  • 실내 공기조화를 하는 거주역에 대한 온열환경요소의 자극 변화를 통해 실내 에너지를 절약할 수도 있으며 쾌적감도 향상시킬 수 있다. 따라서 본 연구에서는 거주자의 온열감각을 자극할 수 있는 온열요소 중 비교적 영향이 크고 용이하게 제어할 수 있는 온도 및 기류의 변동으로 한국인의 온열감각(온냉감, 쾌적감, 만족감)에 미치는 영향을 실험을 통하여 파악하였다. 온도 및 기류별 실험을 통하여 22$^{\circ}C$, 24$^{\circ}C$, 26$^{\circ}C$의 각 온도에 대한 패케지 에어컨의 강, 중, 약 기류에 대한 인체순응 시간과 인체 변화를 파악하였다. 또한 인체순응시간을 고려한 온도 상승 실험을 통하여 24$^{\circ}C$, 26$^{\circ}C$에서 1$^{\circ}C$온도 상승시 인체의 온열쾌적감의 변화를 파악하였으며 온도 상승을 통한 인체 순응시간을 도출하였다. 본 실험을 통하여 초기공조 조건을 24C$^{\circ}C$ 로 한 경우 인체순응을 통한 온도 상승으로 30분 후의 공조중기와 공조후기에 온도 및 기류의 지속적인 변동 자극으로 온냉감은 "약간 서늘하다"를 지속적으로 유지하고 있으며 온도상승으로 인한 쾌적존의 높은 온도에서도 기류의 영향으로 쾌적감은 30분 이후부터 "쾌적"을 지속적으로 유지하는 것을 알 수 있었다. 따라서 본 연구를 통하여 인체순응을 고려한 온도 및 기류의 자극을 통하여 공조초기부터 공조말기의 장시간에도 인체가 지속적인 쾌적성을 유지한다는 것을 알 수 있었다.성을 유지한다는 것을 알 수 있었다.

  • PDF

Participation of central GABAA receptors in the trigeminal processing of mechanical allodynia in rats

  • Kim, Min Ji;Park, Young Hong;Yang, Kui Ye;Ju, Jin Sook;Bae, Yong Chul;Han, Seong Kyu;Ahn, Dong Kuk
    • The Korean Journal of Physiology and Pharmacology
    • /
    • 제21권1호
    • /
    • pp.65-74
    • /
    • 2017
  • Here we investigated the central processing mechanisms of mechanical allodynia and found a direct excitatory link with low-threshold input to nociceptive neurons. Experiments were performed on male Sprague-Dawley rats weighing 230-280 g. Subcutaneous injection of interleukin 1 beta ($IL-1{\beta}$) ($1ng/10{\mu}L$) was used to produce mechanical allodynia and thermal hyperalgesia. Intracisternal administration of bicuculline, a gamma aminobutyric acid A ($GABA_A$) receptor antagonist, produced mechanical allodynia in the orofacial area under normal conditions. However, intracisternal administration of bicuculline (50 ng) produced a paradoxical anti-allodynic effect under inflammatory pain conditions. Pretreatment with resiniferatoxin (RTX), which depletes capsaicin receptor protein in primary afferent fibers, did not alter the paradoxical anti-allodynic effects produced by the intracisternal injection of bicuculline. Intracisternal injection of bumetanide, an Na-K-Cl cotransporter (NKCC 1) inhibitor, reversed the $IL-1{\beta}$-induced mechanical allodynia. In the control group, application of GABA ($100{\mu}M$) or muscimol ($3{\mu}M$) led to membrane hyperpolarization in gramicidin perforated current clamp mode. However, in some neurons, application of GABA or muscimol led to membrane depolarization in the $IL-1{\beta}$-treated rats. These results suggest that some large myelinated $A{\beta}$ fibers gain access to the nociceptive system and elicit pain sensation via $GABA_A$ receptors under inflammatory pain conditions.

실리콘 태양전지를 활용한 공기순환 의복의 태양광 입사각에 따른 효율성 및 쾌적성평가 (Efficiency and Comfort Properties of Silicon Solar Cell Applied Air Circulation Jacket according to the Incident Angle of Sunlight)

  • 이지연;조아라;정예리;김은애
    • 한국의류학회지
    • /
    • 제33권11호
    • /
    • pp.1806-1816
    • /
    • 2009
  • This study analyzes the efficiency of a solar cell attached to an air circulation jacket. A commercially available silicon solar panel was selected and attached at four spots where the body angle was $40-60^{\circ}$ and voltage ($V_{oc}$, V), current ($I_{sc}$, A), and output power (P, W) were measured to determine the efficiency. The solar panel was applied to the outer jacket that operates with two fans to increase the convection that lowers the body temperature. The heavy work of standing, walking, and sweeping of a street sweeper was simulated in the field test. The microclimate within the jacket (with or without a fan) was measured and the subjective thermal, humidity, and comfort sensations were surveyed. SPSS 12.0 statistical package was used for a t-test and Wilcoxon signed-rank test. The results show that the highest efficiency of the solar cell was at the incident angle of $60^{\circ}$ in terms of voltage, current and output power distribution. The microclimate temperature of the air circulation jacket decreased significantly with the high power of the fan and subjects felt cooler than the jacket with a fan at the incident angle of $60^{\circ}$. Air circulation jackets operated by a silicon solar panel showed a significant cooling effect on the wearers.

외부 차양장치의 적용실태에 관한 통계적 분석 (Statistical Analysis on Application of External Solar Shading Devices)

  • 김효중;이철성;윤종호
    • KIEAE Journal
    • /
    • 제16권5호
    • /
    • pp.65-71
    • /
    • 2016
  • Purpose : The solar shading device carries out roles in a reduction of the cooling load and an improvement of the thermal comfort of occupants by adjusting incident solar radiation. In addition, The shading device enhances the visual sensation comfort by controlling the optical properties. In order to improve building performance and comfort of occupancy, interests in application of the shading devices are getting increasing. This study investigated the application and effectiveness of the external shading device design using statistical analysis. The outcome of this paper could be utilized for the realization of status quo and for an estimation of effectiveness of the shading device Method : The period of data gathering was between 2003 and 2014 and total 459 cases of practical building project were investigated. Firstly, this study defined qualification of the shading devices; the shading device should have minimum protruding lengths of 150mm to outside and have the function of shading control. This paper investigated application rate of the shading device in real project, regional rate of application, annual change of application, materials and types. Result : The statistical analysis showed that the application rate of shading devices was 25.7% in total 459 building design projects. The application rate in central and southern region was 25.3% and 27.0% respectively. Meanwhile, Jeju region showed 22.2%, which was the lowest rate although this area needs more shading devices. The application number of the shading device was the smallest in 2007, but the rate gradually increased after that. The applications was the largest in 2014 due to growing interest of the shading devices in the building.

고온조건하에서 소방용 보호복 착용시 주기적 작업과 작업강도에 따른 신체영향 (Effects of Repetitive Work and Workload for body While Wearing Firefighting Protective Clothing in hot conditions)

  • 방창훈
    • 한국화재소방학회논문지
    • /
    • 제32권4호
    • /
    • pp.35-41
    • /
    • 2018
  • 본 연구는 고온조건하에서 소방용 보호복 착용시 주기적 작업과 작업강도가 신체에 미치는 영향을 연구하여 소방공무원의 건강과 안전을 위한 기초자료 구축을 목적으로 한다. 소방전공 대학생(9명)을 대상으로 소방용 보호장구를 착장한 경우, 실험온도 WBGT $30^{\circ}C$에서 작업강도(3, 9 METs)와 주기적 작업(실험 15분, 휴식 15분, 실험 15분) 따른 비교실험을 수행하였다. 실험결과, 작업강도가 3 METs에서 9 METs로 증가함에 따라 실험기간동안 평균피부온도차(33.3%), 고막온도차(242.9%), 심박수(36.2%), 호흡수(53.9%), 운동자각도(81.6%), 온냉감(20.8%), 체중감소(60.0%), 혈당(-4.4%), 젖산(41.7%)가 통계적으로 유의하게 높게 나타났다. 이상의 결과 고온조건하에서 소방용 보호복 착용시 주기적 작업과 작업강도가 신체에 미치는 영향이 매우 크게 나타나는 것으로 판단된다.

착의량을 중심으로 본 농촌지역주민의 계절적응에 관한 연구 (Seasonal Adaptation of Rural Residents with Focus on Clothing Weight)

  • 정영옥
    • 한국의류학회지
    • /
    • 제15권4호
    • /
    • pp.417-430
    • /
    • 1991
  • The purpose of this study is to evaluate the level of seasonal adaptability of rural residents from a viewpoint of clothing weight. In this study, the 631 rural residents of both sexes and all generations were selected from 5 rural districts of Kyunggi, Kangwon, Chungnam, Chonnam and Kyungbuk province, and the survey on clothes worn by subjects carried out 4 times-once in each season-from 1989. 7 to 1990. 4. The clothing weight per a unit body surface area that is the index of clothing insulative value was calculated and the seasonal variations of clothing weight were investigated in each region, sex and age. The results of this study were as follows. 1. The clothing weight changed with the season and that increased in order of summer, autumn and spring, winter. But there was no significant difference between spring and autumn. 2. In general, the clothing weight of males was havier than that of females through out the year But the underwear clothing weight of males was lighter than that of females. 3. There were significant differences of clothing weight among age groups in the spring, autumn and winter and $14\~29$ age group had smallest clothing weight. Clothing weight increased with age above 29 years and decreased with age below 20 years. In the summer there was no significant di florence of clothing weight among age groups except that clothing weight of $14\~19$ age was significantly havier than the others. 4. The thermal sensation of the clothed body was comfortable in the spring, autumn and winter but that was warm in the summer. 5. The seasonal adaptability of rural adults from a viewpoint of clothing weight was relatively good but the children's clothing life had some problem because they wore too much.

  • PDF

의복을 이용한 내한성 향상 훈련이 내열성에 미치는 영향 (The Relationship between Increased Cold Tolerance Resulting from Cool Clothing on Heat Tolerance)

  • 이종민
    • 한국의류학회지
    • /
    • 제21권4호
    • /
    • pp.669-676
    • /
    • 1997
  • The purpose of this study is to examine the effect of the improved cold tolerance resulting from cool clothing in winter on heat tolerance in summer. Ten healthy women were divided into two groups, cold group(C group) (n=5) and warm group(W group) (n=5) . In the previous study, C group was proved that their cold acclimatization was achieved through wearing cool clothing from September to February of the following year, while Wgroup was not proved because of wearing warm clothing during same period. After February, no more clothing training was continued in two groups. To determine the heat tolerance, both groups were exposed from a thermoneutral environment(25$\pm$1$^{\circ}C$, 50$\pm$5% R.H.) to a hot environment (35$\pm$1$^{\circ}C$, 50$\pm$5% R.H.) before and after clothing training, respectively September in 1994 and truly in 1995. Rectal temperature, skin temperatures, thermal sensation and comfort were measured every 10 min., and Os uptake was measured at 10, 45, 85 min. after entering the chamber for 5 min. Body weight was measured before and after the experiment and amount of local sweat was measured during the 90 min long experiment. The results are as follows: Rectal temperatures in 35'c environment of C group were increased after training when compared with before clothing, while those of W group were not changed. But the changes of rectal temperature and heat production during 90 min in hot environment were almost the same in two groups after training. And mean skin temperatures, the changes of mean skin temperatures during 90 min in hot environment, total sweat amount and local sweat amount after training were also the same in two groups. From these results, it might be supposed that the heat loss of two groups were the same but the heat production, especially heat production during rest in C group was higher than in Wgroup. This fact suggests that the increase of rest heat production from cold acclimatization in winter is maintained to summer of the following year. And mild cold acclimatization coming from westing cool clothing does not have a negative effect on heat tolerance.

  • PDF

Effectiveness of low-level laser therapy on recovery from neurosensory disturbance after sagittal split ramus osteotomy: a systematic review and meta-analysis

  • Firoozi, Parsa;Keyhan, Seied Omid;Kim, Seong-Gon;Fallahi, Hamid Reza
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • 제42권
    • /
    • pp.41.1-41.11
    • /
    • 2020
  • Background: Orthognathic surgery such as bilateral sagittal split ramus osteotomy (BSSRO) for the treatment of mandibular deformities is one of the most common procedures in maxillofacial operations that may lead to neurosensory disturbance. In this study, we aimed to evaluate the effectiveness of low-level laser therapy (LLLT) on augmenting recovery of neurosensory disturbance of inferior alveolar nerve (IAN) in patients who underwent BSSRO surgery. Methods: A comprehensive literature search was conducted by two independent authors in PubMed, Cochrane Central Register of Controlled Trials (CENTRAL), Scopus, Embase, and Google Scholar electronic databases. Besides, a manual search of all textbooks and relevant articles were conducted. Searches took place in August 2020 and were limited to published and peer-reviewed articles from 2000 to 2020. All analysis was performed using the comprehensive meta-analysis (CMA) and the STATA MP (version:16) software. The weighted mean difference (WMD) using the inverse variance method and the standard mean difference (SMD) was considered for continuous variables. Results: Seventy-four papers were retrieved after removing duplicate studies and finally, eight studies were assessed for qualitative synthesis and five for meta-analysis. Totally, 94 patients were included in the meta-analysis. Based on the meta-analysis, it was shown that LLLT was not effective in a short interval (0 to 48 h) after surgery, but in a period of more than 1 month after surgery, the positive results of treatment can be observed strikingly. Also, LLLT side/group showed no significant difference in some aspects of neurosensory recovery such as thermal sensation compared to the placebo side/group. Conclusions: The meta-analysis of randomized controlled trials revealed that LLLT generally improves IAN sensory disturbance caused by BSSRO. Further high-quality clinical trials with longer follow-up periods and larger sample sizes are recommended.

비만아동의 온도적응성에 대한 착의훈련 효과 (Effect of Wear Training on Temperature Adaptability of the Obese Children)

  • 정운선
    • 한국의류학회지
    • /
    • 제30권3호
    • /
    • pp.407-411
    • /
    • 2006
  • 본 연구에서는 비만아동의 온도적응능력을 향상시키기 위해 초등학교 4학년$\∼$6학년에 재학 중인 비만아동 13명(남자 6명, 여자 7명)을 대상으로 하여, 10주간의 단기 의복착용훈련 프로그램을 시행한 후 프로그램의 효과를 알아보았다. 프로그램 시행기간 중 아동이 매일 직접 측정한 주택 내 실내온도는 평균 25.1$^{circ}C$였고, 아동이 착용한 체표면적당 의복의 무게(착의량)는 평균 300g/$m^{2}$였으며, 실내온도와 착의량 간에는 유의한 상관이 있었다(p < .01). 프로그램의 시행효과를 구체적으로 알아보기 위해, 23.0$\pm$0.5$^{circ}C$, 50$\pm$5$\%$RH로 조절된 인공기후실에서 실험을 실시하여, 반소매 면 티셔츠(0.13clo)와 T/C 반바지(0.09c1o)를 착용하고 안정상태에 있는 아동의 체온, 피부온, 혈압 및 맥박 등의 생리반응과 쾌적감 및 온랭감의 주관적 감각반응을 프로그램 시행 전후에 측정한 후 얻은 주요 결과는 다음과 같다. 평균피부온은 프로그램 시행전후에 유의한 차이가 없었으나, 전반적으로 체온과 평균혈압은 프로그램 시행 후에 내려갔다(p < .01). 주관적 감각반응에서는 프로그램 시행 후에 여아가 남아에 비해 약간 더 따뜻하게 느꼈고(p < .05), 이에 따라 아동자신이 선택한 쾌적온도는 더 낮은 경향을 나타내었다(p < .1). 이와 같은 연구결과는 비만아동의 행동성 및 자율성 체온조절연구에 유익할 것이나, 보다 명확한 자료를 얻기 위해서는 종합적이고 장기적인 훈련프로그램의 시행이 요구된다.