Local Body Parts Research Articles

Personal cooling strategies to improve thermal comfort in warm indoor environments: Comparison of a conventional desk fan and air ventilation clothing

The study examined and compared the performance of two personalized cooling strategies (conventional desk fan [DF] and air ventilation clothing [VC]) in three warm indoor environments. Two cooling methods were selected so that the effect of different local body parts cooling can be analysed on overall thermal comfort of female participants. Three warm indoor conditions (28.0, 30.0 and 32.0 °C; 50% RH) were selected with an aim to determine maximum possible air temperature which can be maintained indoors without compromising with thermal comfort of inhabitants. Results showed that performance of both the two cooling methods are similar in terms of perceptual responses and mean skin temperatures at all three air temperatures. Mean torso temperatures in VC were significantly lower than those in DF at three studied indoor temperatures. It was concluded that the effect of torso cooling on overall sensations was equivalent to combined forehead-hand cooling for the studied indoor conditions. VC is recommended for indoor and normal office work environments with air temperatures up to 32.0 °C because it can save significant cooling energy as compared to conventional desk fans.

Investigation of thermal comfort and the nozzle usage behaviour in aircraft cabins

In order to understand passengers’ demand for thermal comfort in aircraft cabins, we carried out a measurement of thermal environment parameters and thermal comfort field survey in an aircraft cabin under cruising at altitude in both summer and winter. The results showed that the air temperature studied was always kept within the range of 25℃ to 28℃ and the relative humidity was maintained within the range of 20% to 35%. The Mean Thermal Sensation Vote (MTSV) of passengers’ back and feet was higher than other local body parts, with lower air movement sensation. The MTSV of passengers in winter was higher than that in summer. Due to the muggy thermal environment, more than 60% of passengers advocated that it was necessary to utilize the personal ventilation system. In their usage of the personal ventilation nozzle, more than half of these passengers chose to cool upper body parts, only a minimum number of passengers opened the nozzle to direct airflow to their head. Therefore, we concluded that the position of the personal ventilation nozzle should be as close to the upper body part of a passenger’s body as possible, making it more convenient and effective to regulate passengers’ thermal comfort.

Analysis of partial-body and whole-body static sitting comfort

The whole-body comfort sensation was moderately to highly correlated with local body part comfort sensation in both sitting and driving, in order to understand what exact relationship exists between them, the seating comfort evaluations under the stimulus of four body parts (i.e. backs, waist, hips and thighs) were carried out for 15 subjects separately, subjective ratings on both partial-body and whole-body comfort are derived under different conditions. Impact factor (IF) of the partial-body comfort to whole-body comfort is calculated by the linear regression method, and the main variables are obtained by the stepwise regression algorithm. The most significant local body part in influencing whole body comfort is found at the region of hips, followed by backs, waist and hips. With impact factor analysis on partial body comfort, the results show that the local comfort feeling of waist is most potential to be influenced by other body parts, while the comfort sensitivity of thighs is the lowest.

Enforcement seizures reveal large-scale illegal trade in India's tortoises and freshwater turtles

Illegal trade in tortoises and freshwater turtles (TFTs) for pet, meat and traditional medicine markets in East and Southeast Asia poses significant threats to wild TFTs globally. South Asian countries such as India are believed to be disproportionately large sources of wild TFTs in illegal international markets, but the nature and dynamics of this trade in India are poorly understood. Using data from 223 enforcement seizure reports obtained through systematic online searches, we show that at least 15 of India's 28 TFT species, including 10 IUCN Threatened species, are illegally harvested, with over 58,000 live individuals seized during 2011–15. Geochelone elegans, Geoclemys hamiltonii and Lissemys punctata were recorded in the largest number of seizures and comprised the largest numbers of TFTs seized overall. Nearly 90% of all seizures were from illegal commercial trade, and there were numerous reports of Indian TFTs being transported by road, rail and air within India, as well as to known pet and meat trading hubs in Bangladesh, Thailand, and four other East/Southeast Asian countries. Commercial trade of live TFTs now targets twice as many Indian species as reported in the 1990s. Alongside illegal harvests for local consumption and TFT body parts for traditional East Asian medicines, this illegal trade poses a growing threat to Indian TFTs. Our findings indicate that building awareness and capacity for handling TFT seizures among enforcement agencies, and strengthening international cooperation for law enforcement, are important steps needed for conserving India's endangered tortoises and freshwater turtles.

Thermal experience improvement and thermal requirement difference in bed warming conditions

The human body is exposed to nonuniform thermal environment due to asymmetric bedding coverage of head and covered body. The purpose of the study is to investigate the thermal requirement difference of local body parts during sleep. Experiments were performed both in bed warming and non-bed warming conditions. Twelve healthy postgraduates were recruited as subjects. The thermal states on different local body parts of subjects were obtained via objective measurement and subjective questionnaires. The results showed that thermal comfort during sleep in winter was not in accordance with the thermal neutral state. In order to achieve overall thermal comfort condition, discrepant thermal sensation should be kept be-tween the head and covered body, besides, the disparity in skin temperature was 1.5°C and in TSV was 0.5 between posterior and lateral body part. The study has implications in the energy saving design of the coupled sleeping thermal environment in winter.

Thermal perception and skin temperature in different transient thermal environments in summer

The effects of air temperature up-step and down-step changes within one test which includes one high-level heat exposure stage and two low temperature stages on subjects’ thermal perceptions and skin temperatures were studied. The air temperature of the high-level heat exposure stage was 37°C while the low-level temperatures were 22/26/32°C, thus developing large (C15: 22°C–37°C–22°C), medium (C11: 26°C–37°C–26°C) and small (C5: 32°C–37°C–32°C) step-change conditions. Twenty four healthy subjects were recruited with skin temperatures of seven local body parts sampled. In addition, self-reported symptoms and thermal perceptions including thermal sensation, comfort and acceptability were investigated. Results show asymmetry in overall and local thermal sensation with overall and local ΔTSV after down-steps in C5 and C15 being significantly larger than their counterparts after up-steps. The most sensitive parts are back, arm and leg. Besides, overall thermal sensation change is more intensive than that of any of other local thermal sensations. In the large step-change condition C15, instep temperature contributed most to the fact that more than 45min was needed for mean skin temperature to achieve steady after down-step.

Temperature field of bed climate and thermal comfort assessment based on local thermal sensations

Bed climate is an essential determinant in creating thermal comfort condition during sleep. This study explored the bed climate distribution and thermal sensations of different local body parts. The mean bed temperatures calculated from different measuring points were evaluated based on their sensitivity to the physiological parameter (mean skin temperature) and subjective quantification (thermal sensation vote). The results showed that the mean bed temperature around the middle part of the body (MBTM) was most suitable for use in the study of sleeping thermal comfort. The bed climate was regularly distributed along with human body segments. To reach a whole body thermal comfort condition inside the bed climate, the deviations from thermal neutrality of different local body parts were obtained. In addition, the thermal comfort zone of indoor environment perceived on the face was wider than that on the covered body. People could be in thermal comfort state when they perceived cool on face, and the indoor temperature could be lower with a higher bedding thermal resistance.

Mining Spatial-Temporal Patterns and Structural Sparsity for Human Motion Data Denoising.

Motion capture is an important technique with a wide range of applications in areas such as computer vision, computer animation, film production, and medical rehabilitation. Even with the professional motion capture systems, the acquired raw data mostly contain inevitable noises and outliers. To denoise the data, numerous methods have been developed, while this problem still remains a challenge due to the high complexity of human motion and the diversity of real-life situations. In this paper, we propose a data-driven-based robust human motion denoising approach by mining the spatial-temporal patterns and the structural sparsity embedded in motion data. We first replace the regularly used entire pose model with a much fine-grained partlet model as feature representation to exploit the abundant local body part posture and movement similarities. Then, a robust dictionary learning algorithm is proposed to learn multiple compact and representative motion dictionaries from the training data in parallel. Finally, we reformulate the human motion denoising problem as a robust structured sparse coding problem in which both the noise distribution information and the temporal smoothness property of human motion have been jointly taken into account. Compared with several state-of-the-art motion denoising methods on both the synthetic and real noisy motion data, our method consistently yields better performance than its counterparts. The outputs of our approach are much more stable than that of the others. In addition, it is much easier to setup the training dataset of our method than that of the other data-driven-based methods.

Optical flow-motion history image (OF-MHI) for action recognition

The motion history image (MHI) is a global spatiotemporal representation for video sequences. It is computationally very simple and efficient. It has been widely used for many real-time action recognition tasks. However, the conventional MHI assigns a fixed motion strength to each detected foreground point and then updates it with a small constant for the background point. Local body parts with different movement speeds and durations will then have the same intensity in the MHI. Similar actions may generate indistinguishable MHI patterns. In this paper, we propose a new motion history representation that incorporates both optical flow and a revised MHI. The motion strength of each pixel point is adaptively accumulated by the optical flow length at that location. It is then exponentially updated over time. It can better describe local movements of body parts in the global temporal template. The motion duration is implicitly given by the update rate for better description of various actions in the scene. For action classification, a set of training action samples are first collected and form the basis templates. An action sequence is then constructed as the linear combination of the basis templates. The coefficients of the combination give the feature vector. The Euclidean distance is finally used to evaluate the similarity between the feature vectors. Experimental results on the widely used KTH and Weizmann datasets have shown that the proposed scheme yields 100 % recognition rates on both test datasets with a fast processing rate of 47 fps on $$200\times 150$$ images.

The use of a thermophysiological model in the built environment to predict thermal sensation: Coupling with the indoor environment and thermal sensation

Thermal comfort, influenced by thermal sensation is an important building performance indicator. In this study we discuss the use of a thermophysiological model in the built environment to assess thermal sensation. In the context of this work, the use of CFD to simulate the thermal environmental conditions around a human is analyzed. Experimental data from two independent studies, covering both genders, are used to validate three different, currently available, thermal sensation models: (1) the Predicted Mean Vote index (PMV), (2) the UC Berkeley thermal sensation model and (3) the EN-ISO 14505 standard. Use of such a model is required to link physiological responses to thermal sensation. In this study they have been evaluated for two different steady-state non-uniform thermal environments. The results confirm that the PMV is not capable of predicting whole body thermal sensation when local effects (local skin temperatures and thermal sensation) have a significant influence. The results furthermore indicate that the use of a thermophysiological model (ThermoSEM) in combination with the UC Berkeley model or EN-ISO 14505 standard seems to be promising regarding the prediction of thermal sensation of local body parts and overall thermal sensation under steady-state non-uniform environments. The advantage of using a thermophysiological model in combination with a thermal sensation model is that thermal comfort can be assessed on a more individualized level under complex, daily encountered, thermal environments where local effects play an important role. However, both thermal sensation models need more research before they can be used in daily building design practice.

Relationship between Objective and Subjective Methods in Evaluating Static Discomfort of Car Driver Seat

Objective method alone is insufficient in measuring discomfort of car seats. It is indirect and does not truly convey the perception and feeling of the sitter. A combination of both objective and subjective method gives better evaluation on discomfort. Seat pressure distribution method was adopted to investigate the static characteristic of a seat. The method was found to be statistically repeatable in measuring sitting of fourteen male subjects in static condition. Subjective discomfort through subjective assessment using a valid and reliable self-established questionnaire together with a body pressure map (BPM) showed increasing discomfort as sitting time increase; which is expected. The short term seat pressure distribution was used to be correlated with subjective assessment. Significant and moderate correlation was observed between four local body parts namely the seat pan bolster, thighs, upper back and lower back with overall seat average pressure BPM used in the subjective evaluation. Multiple linear regression model were established; overall discomfort from averaged pressure from BPM can be predicted from right & left buttock, right & left thigh and upper back & lower back. It was found that R-Sq=93.5%, R-Sq (adj) = 83.7% with moderately adequate predictive ability with predicted R-Sq= 46.77%.

Beyond extrastriate body area (EBA) and fusiform body area (FBA): context integration in the meaning of actions

Beyond extrastriate body area (EBA) and fusiform body area (FBA): context integration in the meaning of actions

Thermal sensation and comfort models for non-uniform and transient environments, part II: Local comfort of individual body parts

A three-part series presents the development of models for predicting the local thermal sensation (Part I) and local comfort (Part II) of different parts of the human body, and also the whole-body sensation and comfort responses (Part III). The models predict these subjective responses to the environment from thermophysiological measurements or predictions (skin and core temperatures). The models apply to a range of environments: uniform and non-uniform, transient and stable. They are based on diverse results from literature and from body-part-specific human subject tests in a climate chamber. They were validated against a test of passengers in automobiles. This series is intended to present the rationale, structure, and coefficients for these models so that others can test them and develop them further as additional empirical data becomes available. The experimental methods and some measured results from the climate chamber tests have been published previously. Part II describes a thermal comfort model with coefficients representing 19 individual local body parts. For each part, its local comfort is predicted from local and whole-body thermal sensations. These inputs are obtained from the sensation models described in Part I and III, or from measurements.

Thermal sensation and comfort models for non-uniform and transient environments: Part I: Local sensation of individual body parts

A three-part series presents the development of models for predicting the local thermal sensation (Part I) and local comfort (Part II) of different parts of the human body, and also the whole-body sensation and comfort responses (Part III). The models predict these subjective responses to the environment from thermophysiological measurements or predictions (skin and core temperatures). The models apply to a range of environments: uniform and non-uniform, transient and stable. They are based on diverse results from the literature and from body part-specific human subject tests in a climate chamber. They were validated against a test of passengers in automobiles. This series is intended to present the rationale, structure, and coefficients for these models so that others can test and develop them further as additional empirical data becomes available. The experimental methods and some measured results from the climate chamber tests have been published previously. Part I describes thermal sensation models representing 19 individual local body parts. The models' structure and coefficients were derived by regression of skin and core temperatures against thermal sensation votes obtained in the chamber experiments. The sensation for each local body part is predicted by a logistic function with four inputs: local skin temperature, mean-skin temperature presenting the whole-body thermal state, and the time derivatives of skin and core temperatures representing the response to transients. These inputs can be obtained from thermophysiological computer programs that treat the body as multiple segments.

Driver sitting comfort and discomfort (part I): Use of subjective ratings in discriminating car seats and correspondence among ratings

Several subjective rating schemes were investigated to determine which might be the most effective for use in designing and evaluating car seats, and what relationships exist among these schemes. Participants ( n=27) completed short-term driving sessions, in six combinations of seats (from vehicles ranked high and low on overall comfort), vehicle class (sedan and SUV), and driving venue (lab-based and field). Overall ratings were obtained, as well as separate measures of comfort and discomfort of the whole body and local body parts. No association was found between subjective ratings and a publicly available overall vehicle comfort score (J.D. Power and Associates’ Comfort Score), implying that other factors besides sitting comfort/discomfort (and car seats) account for overall vehicle comfort. Other major results were that contemporary car seats appear to best accommodate those of middle stature, that packages/seats of sedans were preferred over those of SUVs, that separate processes appeared to be involved in determining whole body comfort and discomfort, and that ratings of comfort were most effective at differentiating among the car seats. Finally, a scheme for the use of subjective ratings was suggested: discomfort ratings for ensuring basic seat requirements (pain prevention-oriented) and comfort ratings for promoting advanced seat requirements (pleasure promotion-oriented). Relevance to industry Evidence regarding the advantages and disadvantages of different subjective rating schemes can facilitate future design and evaluation of automotive seats.

A fuzzy neural network model for predicting clothing thermal comfort

This paper presents a Fuzzy Neural Network (FNN) based local to overall thermal sensation model for prediction of clothing thermal function in functional textile design system. Unlike previous experimental and regression analysis approaches, this model depends on direct factors of human thermal response — body core and skin temperatures. First the local sensation is predicted by a FNN network using local body part skin temperatures, their change rates, and core temperature as inputs; then the overall sensation is predicted. This is also performed by a FNN network. The FNN networks are developed on the basis of the Feed-Forward Back-Propagation (FFBP) network; the advantage of using fuzzy logic here is to reduce the requirement of training data. The simulation result shows a good correlation between predicted and the traditional experimental data.

Partial- and whole-body thermal sensation and comfort—Part II: Non-uniform environmental conditions

Subjects were exposed to sequences of partial-body cooling and warming over a period of 3 h. Skin temperatures, core temperature, thermal sensation, and comfort responses were collected for 19 local body parts, and for the whole body. This paper relates local thermal sensations and comfort to skin and core temperatures, and examines how the thermal sensation and comfort perceived for individual body parts affect thermal sensation and comfort perceived for the whole body. Overshoot in sensation and comfort is stronger when local body parts are cooled or warmed than when the whole body experiences a step-change.

Partial- and whole-body thermal sensation and comfort— Part I: Uniform environmental conditions

Subjects exposed to uniform environments were polled for their local and overall (whole-body) thermal sensation and comfort. Sensation and comfort for local body parts vary greatly. In cool environments, hands and feet feel colder than other body parts. The head, insensitive to cold but sensitive to warm, feels warmer than the rest of the body in warm environments. Overall sensation and comfort follow the warmest local sensation (head) in warm environments and the coldest (hands and feet) in cool environments. Subjects evaluate neutral conditions as “comfortable”, never “very comfortable”, and overshoot of sensation and comfort during whole-body step-changes is small.

Skin and core temperature response to partial- and whole-body heating and cooling

1. Human subjects were exposed to partial- and whole-body heating and cooling in a controlled environmental chamber to quantify physiological and subjective responses to thermal asymmetries and transients. 2. Skin temperatures, core temperature, thermal sensation, and comfort responses were collected for 19 local body parts and for the whole body. 3. Core temperature increased in response to skin cooling and decreased in response to skin heating. 4. Hand and finger temperatures fluctuated significantly when the body was near a neutral thermal state. 5. When using a computer mouse in a cool environment, the skin temperature of the hand using the mouse was observed to be 2–3 °C lower than the unencumbered hand.

Primary afferent input to and receptive field properties of cells in rat lumbar area X.

In this study we examined the primary afferent input to rat area X of Rexed, and characterized sensory receptive fields (RFs) of the cells therein. This poorly understood area contains primary afferent fibres, some of which are arranged into a compact bundle beneath the central canal. Anterograde transport of the B fragment of cholera toxin (CTB) from the sciatic nerve showed a strictly ipsilateral projection to segments in L4 and L5 but both ipsi- and contralateral projections in L6 and more caudal segments. The response of cells in area X to mechanical cutaneous stimuli was recorded through extracellular microelectrodes in decerebrate, decerebrate-spinal, and urethane-anaesthetised preparations. The lateral edge of area X was marked by an abrupt change in the RFs: Lateral to area X in the dorsal horn, they were strictly unilateral and relatively small. At a mean of 90 microm from the midline, there was an abrupt expansion of the RFs to cover at least the entire ipsilateral dermatome. Within area X, 70% of the cells' RFs extended across the midline to include contralateral skin. In 35% of cells recorded in rats with intact spinal cords, the RF extended rostrally onto the forelimb. In a small number of cells, the RF included ear pinnae and nose. The precise function of area X cells remains unknown; although they have been shown to be involved in visceral reflexes, the fact that they receive convergent input from a wide variety of tissues and from local and remote body parts implies a more generalized, integrative function.