Digital imaging,spectroscopy, and liquid crystals in a hand‐held,non‐invasive device to determine hemoglobin concentration

Abstract— Anemia is a significant public‐health concern both in the United States and throughout the world. This disorder of low hemoglobin concentration in the blood, which often lurks undetected for long periods, contributes significantly to mortality and morbidity and is a major cause of lost revenues from workforce shortfalls, particularly in developing countries where the incidence of anemia is higher due to malnutrition and parasitic disease. The gold standard for measuring hemoglobin is a blood test requiring phlebotomy and laboratory quantification. Current physical examination techniques and non‐invasive adjuncts for detecting anemia are not sensitive and are subject to user variability. There is an urgent need for a hand‐held device which can measure hemoglobin concentration accurately, inexpensively, and non‐invasively. The evolution of a device from its early inception, which analyzed color decomposition in a digital image of the eyelid, to its final version that is a light, inexpensive, hand‐held, non‐invasive device utilizing liquid crystals to delineate the spectroscopic characteristics of the reflected light from the palpebral conjunctiva (the inside of the lower eyelid which contains many small blood vessels) and determine hemoglobin concentration in the circulating blood will be discussed. The future refinements required for bringing such a device to the market will also be discussed.     

Comfort of personal protective equipment

The degree of comfort of personal protective equipment (PPE) was investigated in an automobile encapsulating plant. Up to 96.2% of employees used one or a combination of PPE. Only 8% of the workers felt their respirators were comfortable, 30% tolerated their respirators, and 62% rated them as uncomfortable. The percentage of employees who rated their PPE (other than a respirator) as comfortable ranged from 32 to 52%. For comfort factor, coveralls/aprons rated 52%, safety glasses 51%, rubber gloves 42%, and hearing protectors 36%. PPE was tolerable (just acceptable) for about 30% of the employees. To increase the effectiveness and safety of PPE, the human-factor aspects of PPE design should be emphasized more and quality improvement should cover the wearability of PPE.     

A qualitative study on the comfort and fit of ladies' dress shoes

The perceived differences between comfortable and uncomfortable shoes and the fit preferences in the different regions of ladies' shoes were explored. Twenty Hong Kong Chinese females participated in the study. Each participant wore and rated the different aspects of their own comfortable and uncomfortable shoes. The Wilcoxon signed rank tests showed significant differences in ten perceived characteristics between the comfortable and uncomfortable shoes. Among the ten were tactile, auditory and olfactory sensations. The ten items reliably (Cronbach alpha>0.9) distinguished between comfortable and uncomfortable shoes. There were no significant differences between comfortable and uncomfortable shoes for aesthetic-related characteristics. Further analysis on the fit ratings showed a significant impact on the fit preferences in the Toe region (p<0.0001), Metatarsophalangeal (MPJ) region (p<0.0001), Arch region (p=0.002) and Ingress/egress opening (p<0.001). Knowing the preferred type of fit can help establish a specification for comfortable shoes and also brings out the criteria that a comfortable shoe does not necessarily have the same perceived fit in every region of a shoe.     

Announcing the new EiC

As I mentioned in my last editorial, my term as editor-in-chief (EiC) of the magazine is coming to an end, and it is my great pleasure to announce that the new EiC of the magazine will be Dr. Peter Corke from CSIRO in Australia. I am extremely happy and comfortable to leave the magazine to Peter who is not only an extremely distinguished scientist but also a motivated leader and pleasant person who will take care with dedication to keep the high level of the magazine and further improve it.     

Comfortable with friends sharing your picture on Facebook? - Effects of closeness and ownership on picture sharing preference

Picture sharing activity on social networking sites helps create and maintain social relationships. However, some of these pictures can be undesirable digital traces especially when the person sharing the information (owner) and the person receiving the information (viewer) do not ask the sharing preference of the person who is in the picture (subject). In our exploratory lab study, we asked twenty-nine participants about their picture sharing preference (PSP) towards an owner's act of sharing a photograph containing both the participant (subject) and the owner with a viewer. Our multi-level regression on 5520 data points show that in terms of closeness, a subject feels more comfortable sharing a picture i) as the “closeness between the subject and the owner (SO closeness)” increases and ii) as the “closeness between the subject and the viewer (SV closeness)” increases. In terms of ownership, a subject feels more comfortable with sharing a picture i) when the picture shows a greater number of people as opposed to a smaller number of people, and ii) when the picture is captured at an event held for the viewer or the owner rather than for the subject. In addition, we observed three types of interaction effects on PSP between the following variables: i) SO closeness and SV closeness, ii) SO closeness and num_people, and iii) both types of closeness and event_posessor.     

Touchable objects: attributes applied to the design of computer input devices

Among many important attributes, designers often seek to create products that are comfortable both in the sense of avoiding discomfort and providing a positive sense of comfort. Another way of looking at the design of hand-held products is to consider what attributes make a product enjoyable to touch, rather than just comfortable or uncomfortable. A series of focus discussions investigated the qualities of objects that are enjoyable to touch. Persons were asked to bring in one or two objects that said to them, "Touch me" and "Keep touching me". Discussion with the participants discerned their motivations for selecting the touchable objects. Observations noted the objects' sizes, weights, shapes, surfaces, and colours. This research about qualities of touchable objects influenced the designs of new designs of trackballs for computer navigation. Further hypothesis supposes that the attributes of touchable objects are based on human experience over time with nature.     

Preference for newspaper size

The past few years has seen a change in the size of newspapers, with publishers moving to a smaller size format. Five ‘standard’ newspaper sizes are used in different countries: Broadsheet, Rhensch, Tabloid, Tall Tabloid and Berliner. These papers vary in both width and height of pages and hence there are implications for human reading comfort, which may be dependent on reading location such as on a lounge chair or on a train. Experiments were carried out to determine preferences for the different sizes and to relate these preferences to the geometric characteristics of the newspapers. For both comfortable and cramped/uncomfortable reading conditions, the rank order of preference for paper types was, from least to most-preferred, Broadsheet, Rhensch, Berliner, Tall Tabloid and Tabloid. Preferences were much stronger when determined in cramped/uncomfortable reading conditions, where most comparisons were significantly different. There was good correlation between participant ratings on several scales and preference, where most factors were related to comfort of holding and controlling the paper.     

Family Strategies in Hungary: The Role of Undocumented Migrants in Eldercare

In Hungary until recently there are no research data on undocumented migrants working in the field of eldercare. Qualitative research conducted in 2009–2011 examined this ‘invisible’ segment working in long-term care. One of the target groups this study was families employing undocumented migrants including ethnic Hungarians from neighbouring Romania (Transylvania) and Ukraine (Subcarpathia). The paper explores this data to address where the employment of invisible migrants appears in the long-term eldercare strategies of Hungarian families. In addition, this paper examines the role of Hungarian non-migrant carers who are also present on the illegal (black) labour market providing eldercare. Based on analysis of macro data and empirical research, the paper identifies several care strategies utilised by families caring for older people in Hungary: 1. Active family carer; 2. Inactive family carer; 3. Family carer receiving a care allowance; 4. Family care with shared responsibility; 5. Family employing legal carer; 6. Family employing undocumented non-migrant carer; 7. Family carer also with earnings on the black market; and 8. Family employing undocumented migrant carer. This paper also highlights that a decline in the trend of migration in the near future will bring an erosion of the existing care source that has not been anticipated by policy related to eldercare. The increase in the retirement age causes women’s later exit from the labour market, aggravating the problem of balancing care and work. This increase in the retirement age, considered to be essential for ensuring the sustainability of the pension system, will inevitably result in a shortage of services with all its financial and structural implications. As women will no longer be able to perform care tasks, the formal care system will be unable to cope with the extra demand.     

How do thermal conditions in intensive care units affect the health and well-being of intensivists?

This study presents situational risk scenarios to predict the potential implications of predicted and perceived thermal configurations on the health and well-being of health care professionals in intensive care units (ICUs). Nine ICUs were selected, and thermal variables were collected; simultaneously, 128 health care professionals were interviewed to assess their perceptions, satisfaction, and health conditions related to their workplace environment. In scenarios with thermal comfort (either predicted or perceived), the risk of exposure to physical and psychological symptoms was reduced. This effect also extends to predictions and perceptions tending toward slightly cooler temperatures. In situations with a predicted mean vote below −1.5 and above 0.5, symptom complaints increased, even when the health care professionals perceived their environment as thermally comfortable, with the most extreme cases generating an increase of up to 27% in the baseline probability. Adjusting the workplace environment to be thermally comfortable can reduce symptom complaints.     

Touchable objects: attributes applied to the design of computer input devices

Among many important attributes, designers often seek to create products that are comfortable both in the sense of avoiding discomfort and providing a positive sense of comfort. Another way of looking at the design of hand-held products is to consider what attributes make a product enjoyable to touch, rather than just comfortable or uncomfortable. A series of focus discussions investigated the qualities of objects that are enjoyable to touch. Persons were asked to bring in one or two objects that said to them, ‘Touch me’ and ‘Keep touching me’. Discussion with the participants discerned their motivations for selecting the touchable objects. Observations noted the objects' sizes, weights, shapes, surfaces, and colours. This research about qualities of touchable objects influenced the designs of new designs of trackballs for computer navigation. Further hypothesis supposes that the attributes of touchable objects are based on human experience over time with nature.     

Load balancing of dynamical distribution networks with flow constraints and unknown in/outflows

We consider a basic model of a dynamical distribution network, modeled as a directed graph with storage variables corresponding to every vertex and flow inputs corresponding to every edge, subject to unknown but constant inflows and outflows. As a preparatory result it is shown how a distributed proportional–integral controller structure, associating with every edge of the graph a controller state, will regulate the state variables of the vertices, irrespective of the unknown constant inflows and outflows, in the sense that the storage variables converge to the same value (load balancing or consensus). This will be proved by identifying the closed-loop system as a port-Hamiltonian system, and modifying the Hamiltonian function into a Lyapunov function, dependent on the value of the vector of constant inflows and outflows. In the main part of the paper the same problem will be addressed for the case that the input flow variables are constrained to take value in an arbitrary interval. We will derive sufficient and necessary conditions for load balancing, which only depend on the structure of the network in relation with the flow constraints.     

Comparing response latency and self-report methods for estimating levels of certainty in knowledge elicitation for rule-based expert systems

Many practitioners and theoreticians feel uncomfortable in using classic self‐report, knowledge acquisition methods for assessing an expert’s feelings of confidence or certainty about rules, choices or decisions. This paper proposes and tests an alternative approach using response latency, or the time it takes an expert to respond to a paired choice inquiry. The question is to learn if there is any merit in considering the response latency approach as a replacement for the classic method. This investigation is concerned with using the analytic hierarchy process (AHP) to compare two methods for estimating a subject’s feeling of certainty or confidence about their rule, choice or decision. One method is the older or classic method where a subject self‐reports both the choice selected and the level of certainty associated with a choice‐pair on the 1‐to‐9 scale used with the AHP. The second is proposed by the authors and based on using only the choice and decision time or response latency. In the second case, the inverse of response latency is used to estimate a subject’s degree of certainty or confidence in the selected choice in a paired comparison experiment. The response latency method has the advantage of being unobtrusive, less prone to conscious censure, quicker to perform, requiring less effort, and possibly being less expensive to administer. Employing AHP methodology, priorities are used to represent the degree of confidence among choices or rules, and consistency ratios are used to estimate the degree of consistency detected by each method. To compare the two methods, 21 subjects were evaluated in a paired sample design. Employing a computer‐administered questionnaire, subjects expressed relative levels of confidence for a set of potential recommendations and the time for each subject to respond was recorded unobtrusively. Using paired sample t tests, sufficient evidence was found to reject the null hypothesis (α= 0.025) that the mean of the difference in the priorities between the two methods was zero (p < 0.0001). In a second test, there was sufficient evidence to be at least 95% confident of accepting an alternative hypothesis that response latency produces a lower consistency ratio (higher consistency of the reports) than the self‐report method (p < 0.0001). In addition to the tests of significance, the results were found to be practically significant and are discussed in the paper.     

Individual Differences in Response to the Environment

In assessing the effects of environmental stress three points are made.

1. Comfort and working efficiency cannot necessarily be equated.

2. The optimal experimental design for assessing individual differences differs fundamentally from that required for establishing population means. Reliable individual differences will only be revealed by repeated measures of a given effect upon the same people and under the same conditions.

3. Regarding the assessment of what individuals find comfortable as regards temperature, or acceptable as regards noise, two difficulties are noted, (a) In terms of what they are prepared to do about it individuals may differ in what they mean when they tick one of a number of terms indicating varying degrees of discomfort or annoyance. (b) Where an observer experiences a range of conditions he will tend to place the centre point of the rating scale at the centre of the range of conditions sampled. Over a group of observers this may bias the average comfort or acceptability vote away from its true point. It may also artefactually increase the variation between individuals who receive conditions in different orders of presentation, On the other hand differences between groups of observers, for example young and old, may be minimised if the same range of conditions is presented to all. The presentation of a standard followed by a single test condition will avoid difficulties due to range effects but may encounter others due to suggestion or contrast effects.     

基于状态聚类的多站点CSPS系统的协同控制方法

单站点传送带给料加工站（Conveyor-serviced production station,CSPS）系统中,可运用强化学习对状态——行动空间进行有效探索,以搜索近似最优的前视距离控制策略.但是多站点CSPS系统的协同控制问题中,系统状态空间的大小会随着站点个数的增加和缓存库容量的增加而成指数形式（或几何级数）增长,从而导致维数灾,影响学习算法的收敛速度和优化效果.为此,本文在站点局域信息交互机制的基础上引入状态聚类的方法,以减小每个站点学习空间的大小和复杂性.首先,将多个站点看作相对独立的学习主体,且各自仅考虑邻近下游站点的缓存库的状态并纳入其性能值学习过程;其次,将原状态空间划分成多个不相交的子集,每个子集用一个抽象状态表示,然后,建立基于状态聚类的多站点反馈式Q学习算法.通过该方法,可在抽象状态空间上对各站点的前视距离策略进行优化学习,以寻求整个系统的生产率最大.仿真实验结果说明,与一般的多站点反馈式Q学习方法相比,基于状态聚类的多站点反馈式Q学习方法不仅具有收敛速度快的优点,而且还在一定程度上提高了系统生产率.     

可穿戴心电信号采集与分析系统的设计与实现

针对传统心电采集设备的移动限制性以及佩戴的不舒适性,根据可穿戴计算特点,设计并实现了穿戴式心电采集与分析系统。系统采用自主研发的12/单导联心电采集模块进行心电信号采集,数据可存于采集设备或经3G网络传输到服务器端,同时所开发的软件可对心电图进行辅助病情分析,实现对佩戴人的心电监护。还研究并制作了插入式电极和织物电极,并通过二者的结合提高了采集心电信号的质量。实际佩戴和使用结果表明,使用插入式织物电极的可穿戴式心电采集设备具有良好的舒适性,心电信号波形的质量能够达到临床监控的要求。     

Linear state estimation for Markov jump linear system with multi-channel observation delays and packet dropouts

This paper is to investigate the linear minimum mean square error estimation for Markovian jump linear system subject to unknown Markov chains, multi-channel mode and observation delays, and packet losses. The reorganisation method is employed to convert the delayed measurement system into an equivalent delay-free one and a new state variable is introduced, by which the original state estimation with transmission delays and data losses is transformed into the new state estimation for the reorganised delay-free system with jumping parameters and multiplicative noises. The new state estimation is derived via the innovation analysis method, and an analytical solution to the estimator is given in terms of a set of generalised Riccati difference equations based on a set of coupled Lyapunov equations. Then the original state estimation will be obtained via the jumping property. Finally, we show that the difference Riccati equations converge to a set of generalised algebraic Riccati equations under appropriate assumptions, which result in an optimal stationary filter.     

ForgetMeNot: What and how users expect intelligent virtual agents to recall and forget personal conversational content

An important aspect of human interaction is our ability to store, retain, recall and organise information. Memory assists in building rapport and gaining trust. The growing field of artificial companions involving long term and casual/social relationships will require appropriate handling of memories of the user by an Intelligent Virtual Agent (IVA). This is a first study to determine what types of personal information (i.e., domain/task and casual/social) users expected an IVA to discuss and remember and how users responded to various levels of IVA recall and forgetting of that information: complete recall; total loss of recall; partial recall and incorrect recall. Our experiment collected conversations and survey responses from participants who interacted with a virtual real estate agent according to one of two treatments over three experimental sessions. No significant differences were found in participants׳ responses between task-focused or casual/social content, however a larger sample size may produce different results and some participants were not comfortable with answering the social questions. Recall was found to increase the user׳s enjoyment of interacting with the agent and also to increase the believability of the character over multiple interactions. We found that characters who recall information incorrectly are highly frustrating, are seen as having unnatural memory and this decreases the believability of the character. However, characters that exhibit forgetting, either explicitly stating their forgetfulness or not mentioning it at all, are seen to have a more natural memory and can help to increase the believability of the character. The study also suggests that forgetting affects the level of trust the user feels for the character.     

An efficient deconvolution algorithm for estimating oxygen consumption during muscle activities

The reconstruction of an unknown input function from noisy measurements in a biological system is an ill-posed inverse problem. Any computational algorithm for its solution must use some kind of regularization technique to neutralize the disastrous effects of amplified noise components on the computed solution. In this paper, following a hierarchical Bayesian statistical inversion approach, we seek estimates for the input function and regularization parameter (hyperparameter) that maximize the posterior probability density function. We solve the maximization problem simultaneously for all unknowns, hyperparameter included, by a suitably chosen quasi-Newton method. The optimization approach is compared to the sampling-based Bayesian approach. We demonstrate the efficiency and robustness of the deconvolution algorithm by applying it to reconstructing the time courses of mitochondrial oxygen consumption during muscle state transitions (e.g., from resting state to contraction and recovery), from the simulated noisy output of oxygen concentration dynamics on the muscle surface. The model of oxygen transport and metabolism in skeletal muscle assumes an in vitro cylindrical structure of the muscle in which the oxygen from the surrounding oxygenated solution diffuses into the muscle and is then consumed by the muscle mitochondria. The algorithm can be applied to other deconvolution problems by suitably replacing the forward model of the system.     

Wrist strength is dependent on simultaneous power grip intensity

The effect of grip activities on wrist flexion/extension strength was examined. Twelve healthy subjects performed maximum wrist flexion/extension exertions with one of five levels of simultaneous grip effort: minimum effort; preferred effort; 30%, 60% and 100% maximum voluntary contraction. As grip force increased from the minimum to the maximum effort, average wrist flexion strength increased 34% and average wrist extension strength decreased 10%. It appears that the finger flexor tendons on the volar aspect of the wrist act agonistically in wrist flexion and act antagonistically to wrist extension. When an object gripped by the hand is fragile or uncomfortable, the reduced finger flexor activity will limit wrist flexion strength. Gripping a slippery object that requires high grip effort will result in reduced wrist extension strength. Grip force should be controlled during measurement of wrist flexion or extension strength. When analysing a task that involves both grip and wrist exertions, use of grip/wrist strength values that were measured during grip exertions only, or wrist exertions only, may incorrectly estimate the true grip/wrist strength, as grip and wrist activities significantly interact with each other as demonstrated in this paper.     

Wrist strength is dependent on simultaneous power grip intensity

The effect of grip activities on wrist flexion/extension strength was examined. Twelve healthy subjects performed maximum wrist flexion/extension exertions with one of five levels of simultaneous grip effort: minimum effort; preferred effort; 30%, 60% and 100% maximum voluntary contraction. As grip force increased from the minimum to the maximum effort, average wrist flexion strength increased 34% and average wrist extension strength decreased 10%. It appears that the finger flexor tendons on the volar aspect of the wrist act agonistically in wrist flexion and act antagonistically to wrist extension. When an object gripped by the hand is fragile or uncomfortable, the reduced finger flexor activity will limit wrist flexion strength. Gripping a slippery object that requires high grip effort will result in reduced wrist extension strength. Grip force should be controlled during measurement of wrist flexion or extension strength. When analysing a task that involves both grip and wrist exertions, use of grip/wrist strength values that were measured during grip exertions only, or wrist exertions only, may incorrectly estimate the true grip/wrist strength, as grip and wrist activities significantly interact with each other as demonstrated in this paper.