Human Courier Research Articles

Modeling an on-demand meal delivery system with human couriers and autonomous vehicles in a spatial market

This paper investigates the impacts of introducing autonomous vehicles (AVs) into an on-demand meal delivery system at a strategic level. The proposed model consists of (i) a microscopic physical model describing the delivery process for bundled orders and (ii) a macroscopic network equilibrium model characterizing the interactions among customers, human couriers (HCs), and AVs, as well as couriers’ repositioning behaviors in the market. A tailored algorithm based on the Alternating Direction Method of Multiplier (ADMM) is developed to solve the platform’s optimal pricing and maximize its profit. To investigate the impact of AV operations, we test three AV distribution rules, i.e., distributing AVs evenly in the space (Rule 0), proportional to demand (Rule 1), and inversely proportional to demand (Rule 2). The numerical experiments show that Rule 2 archives the maximum platform profit, along with the highest service throughput and the hourly earning rate of HCs. Nevertheless, the numerical experiments adopting the parameters calibrated by current market conditions show that the employment of AVs does not show significant benefits to the platform or other stakeholders. It can only generate a higher platform profit when the AV operation cost is lower than HCs’ hourly earnings in a purely labor-based MDS system. As the AV fleet size expands, the improvement of service quality is rather minor meanwhile the hourly earning of HCs drops substantially.

Comparative Validation Study between Pneumatic Tube System and Hand Carried Blood Sample

Rapid delivery of specimens is crucial in today's clinical laboratories, and pneumatic tube systems are commonly utilized for this purpose. The validation of sample stability through pneumatic tube system (PTS) is essential. The use of Pneumatic Tube System can improve specimen turnaround time; allowing more effective time management of the porters by reducing the need to physically take specimens from one department to another. Prior to use, the Pneumatic tube system must be validated to ensure the reliability of laboratory test results, particularly those impacted by movement, such as lactate dehydrogenase (LDH), aspartate aminotransferase (AST), potassium (K+), complete blood count (CBC), particularly hemoglobin and coagulation tests. The most common way of validating pneumatic tube systems is to compare blood samples transported by pneumatic tube systems to blood samples transported by hand. High speeds and rapid acceleration of blood samples can increase the risk of hemolysis and negatively affect sample quality and test results. Moreover, the installation and design of each pneumatic tube system exhibit unique characteristics that are exclusive to each individual institution. The established protocol necessitated the use of either a human courier or pneumatic tube technology in order to transport a collection of replicated samples to the laboratory. Comparative research will be conducted on a sample size of twenty healthy adult volunteers to assess the integrity of the sample. The main objective of our study was to evaluate the effects of PTS transportation on laboratory results and whether is there any difference as compared to hand courier method.

When drone delivery meets human courier: A co-sourcing perspective

With the constantly rising labor cost and deterioration in traffic congestion, the drone-based service emerges as a game changer for the urban last-mile delivery. Meanwhile, the human courier, as a traditional player in the last-mile delivery, appears as a typical form of gig economy, which is always available but with less revenue to harvest. To help the retailer with the fleet sizing decision-making, a co-sourcing mechanism is introduced, which is by nature a time-varying queue with a finite waiting space. And the orders are subject to cancellation when the waiting exceeds the customers’ patience time. Furthermore, three stochastic optimization models are formulated, namely, the pure stability, the pure profit, and the hybrid models, to jointly determine the optimal waiting space threshold and the drone fleet size, which are then approximated with fluid models. Based on the optimal control theory, the optimal decisions are obtained according to the outsourcing probability and time delay. As validated in the simulation, the proposed pure stability model can effectively stabilize the system performance at the control target, while the hybrid model takes into account both the stability and the profit. Finally, the tradeoff between profitability and volatility is analyzed, and the impacts of the parameters on the overall system performance are revealed.

Impact of blood collection devices and mode of transportation on peripheral venous blood gas parameters

BackgroundPeripheral venous blood (PVB) gas analysis has become an alternative to arterial blood gas (BG) analysis in assessing acid-base balance. This study aimed to compare the effects of blood collection devices and modes of transportation on peripheral venous BG parameters. MethodsPVB-paired specimens were collected from 40 healthy volunteers into blood gas syringes (BGS) and blood collection tubes (BCT), transported by either a pneumatic tube system (PTS) or human courier (HC) to the clinical laboratory, and compared using a two-way ANOVA or Wilcoxon signed-rank test. To determine clinical significance, the PTS and HC-transported BGS and BCT biases were compared to the total allowable error (TEA). ResultsPVB partial pressure of oxygen (pO2), fractional oxyhemoglobin (FO2Hb), fractional deoxyhemoglobin (FHHb), and oxygen saturation (sO2) showed statistically significant differences between BGS and BCT (p < 0.0001). Compared to HC-transported BGS and BCT, statistically significant increases in pO2, FO2Hb, sO2, oxygen content (only in BCT) (all p < 0.0001), and base excess extracellular (only in BCT; p < 0.0014) concentrations and a statistically significant decrease in FHHb concentration (p < 0.0001) were found in BGS and BCT delivered by PTS. The biases between PTS- and HC-transported BGS and BCT exceeded the TEA for many BG parameters. ConclusionsCollecting PVB in BCT is unsuitable for pO2, sO2, FO2Hb, FHHb, and oxygen content determinations.

Notorious: Animal passions in the desert: Lions, camels and a human, oh my!

Abstract“You believe animals to be wholly deprived of passions” asks the narrator of Balzac's 1836 story, “A Passion in the Desert,” and he adds, “you should know that we can give them all the vices driven by our state of civilization.” It is in the context of Balzac's questioning of animal passion that I would like to consider the striking and passionate expressions shared among the lion, dromedary and human figures in Jules Verreaux' “Lion Attacking a Dromedary.” The denial of animal passion can be understood as a Cartesian legacy that influenced both taxidermy and the illustrations of early natural histories, but would eventually be questioned during the 18th and 19th centuries. Thus, Buffon accepted that an animal might be excited or moved by passions, but also wrote that any depiction of that agitation could only distort the representation of a species' essence. During the 19th century, by contrast, both scientific and artistic representations of animals show an increasing interest in animal emotions, even as these would underscore a greater affinity between human and non‐human animals, as evidenced by Darwin's 1872 publication of The Expression of the Emotions in Man and Animals. Balzac's story and Verreaux's taxidermy question to what extent passions humanize animals or bestialize humans, a question with potential relevance, I will argue, for understanding how the vices of civilization might relate to the figure of the human Courier in the exchange of passions.

Multi-Location Assortment Optimization with Drone and Human Courier Joint Delivery

This paper studies the constrained multi-location assortment optimization problem under joint delivery by drone and human courier. To maximize the revenue of the retailer, product assortment and last-mile delivery methods are configured simultaneously. To handle the joint delivery problem with product assortment, a mixed multinomial logit model is established to depict the customer purchase behavior. We also take into account the load capacity of drones and the delivery distance limit of drones and human couriers. To the best of our knowledge, the present paper is the first to study the assortment optimization problem considering joint delivery by drone and human courier. The problem is first formulated as a mixed-integer linear programming (MILP) model, which is then transformed into a conic quadratic mixed-integer model with McCormick inequalities (Conic + MC). In the numerical study, it is demonstrated that Conic + MC outperforms MILP as Conic + MC finds the optimal solution within 300 s, while MILP needs more than 600 s. Furthermore, several management insights are revealed for retailers regarding assortment planning when facing different kinds of product revenue structures, and advice is provided for online ordering platforms in terms of setting delivery limits.

Creation of a Multi-vendor Image-Sharing Solution.

Transferring medical imaging studies from one institution to another is a common occurrence in today's medical practice. For the past two decades, radiology departments have relied on physical media (compact discs and digital video disks) and human couriers to accomplish image transfer. This mode of transfer is slow, prone to failure, and reliant on outdated technology. To address these shortcomings, multiple image-sharing vendors have created electronic, cloud-based solutions. While these solutions solve multiple problems, a new problem has been introduced: it is difficult to send or receive images across image-sharing platforms. In this work, we describe how we have developed a solution to share images across multiple vendor platforms.

Falsely decreased FVIII activity following pneumatic tube transport.

The pneumatic tube system (PTS) is widely used for sample delivery. We aimed to investigate the impacts of PTS on hemostasis assays. Triplicate samples from 30 healthy volunteers were delivered to the core laboratory manually by human courier or via the 500m long-distance PTS or via the 1000m long-distance PTS. Comparisons of 19 hemostasis tests were conducted. Although PT, INR, APTT, FII, FV, FVII FIX, FX, FXII, DD, α2-PI, and PC had statistical significance (all P<.05), all had low average bias remaining withinclinical acceptable limits. PTS transportation only resulted in a statistically significant and clinically relevant decrease in FVIII activity. In the 500m-PTS group, 66.7% (20/30) of samples for FVIII testing had a bias greater than 8.3%. Moreover, in the 1000m-PTS group, 96.7% (29/30) of samples had a bias of over 8.3%, and the maximal bias achieved 42.1%. Pneumatic tube system in our institution could be used to deliver blood samples for hemostasis tests evaluated in this study except FVIII activity assay.

Watching information flow inside cells

Single-Cell Methods Each human cell has an information network like a subway system underpinning the function of one of the world's major cities. Instead of human couriers, within our cells, messenger RNAs (mRNAs) carry information. Thousands of mRNAs emerge from the cell's nucleus with instructions for cellular functions and disappear into the cytoplasm when their duties are fulfilled. Because of the development of single-cell sequencing techniques, we are now very good at counting these messengers, which are specific to each cell type in our body. Qiu et al. developed a new method to watch the movement of mRNAs. The technique can distinguish newly synthesized mRNAs from older ones and track each mRNA with a specific tag. This method provides a picture of the information flow inside cells and shows how they become disrupted by genetic perturbations that can cause cancer. Nat. Methods 17 , 991 (2020).

Comparison of in-sight and handheld navigation devices toward supporting industry 4.0 supply chains: First and last mile deliveries at the human level

Last (and First) mile deliveries are an increasingly important and costly component of supply chains especially those that require transport within city centres. With reduction in anticipated manufacturing and delivery timescales, logistics personnel are expected to identify the correct location (accurately) and supply the goods in appropriate condition (safe delivery). Moving towards more environmentally sustainable supply chains, the last/first mile of deliveries may be completed by a cyclist courier which could result in significant reductions in congestion and emissions in cities. In addition, the last metres of an increasing number of deliveries are completed on foot i.e. as a pedestrian. Although research into new technologies to support enhanced navigation capabilities is ongoing, the focus to date has been on technical implementations with limited studies addressing how information is perceived and actioned by a human courier. In the research reported in this paper a comparison study has been conducted with 24 participants evaluating two examples of state-of-the-art navigation aids to support accurate (right time and place) and safe (right condition) navigation. Participants completed 4 navigation tasks, 2 whilst cycling and 2 whilst walking. The navigation devices under investigation were a handheld display presenting a map and instructions and an in-sight monocular display presenting text and arrow instructions. Navigation was conducted in a real-world environment in which eye movements and device interaction were recorded using Tobii-Pro 2 eye tracking glasses. The results indicate that the handheld device provided better support for accurate navigation (right time and place), with longer but less frequent gaze interactions and higher perceived usability. The in-sight display supported improved situation awareness with a greater number of hazards acknowledged. The benefits and drawbacks of each device and use of visual navigation support tools are discussed.

Can the Subaltern Fly? Female Bodies in Molano’s and Marston’s Narcofiction

Within the vast tradition of Latin American cultural production related to the phenomenon of narcotrafficking, this article focuses on two recent emblematic works of narcofiction that illustrate the connections between air travel and Colombian human courier drug smuggling. The first is “El arriero” (“The Mule Driver”), one of a collection of stories by Colombian journalist and author Alfredo Molano included in his book Rebusque mayor. Relatos de mulas, traquetos y embarques (1994). The second is the film Maria Full of Grace (2004), written and directed by American filmmaker Joshua Marston. A comparison of these two cultural productions on drug-muling identifies specific patterns of the transnational illicit drug trade fostered by contemporary global air These works are also deeply related to gender discrimination and violence, aggravated by socioeconomic issues specific to Latin America and the Global South.... This parallel between a locally produced Colombian short story and a successful American film targeted for an international audience demonstrates how the phenomenon of transnational drug smuggling is critically explored, respectively, by the dominant Western and Southern society, highlighting patterns of subalternity, gender inequality, and distorted mobility.

Cartel de los sapos I y Alias el mexicano

Objetivos: identificar los estereotipos de mujer representados en narcoseries colombianas y su relación con la trasmisión de mensajes de empoderamiento del tercer Objetivo de Desarrollo del Milenio (Autonomía en Toma de decisiones, Autonomía Física y Autonomía Económica), que busca generar equidad entre los géneros y empoderar a la mujer.&#x0D; Metodología: se tomó como muestra dos narcoseries con alto rating: “El cartel de los sapos I” y “Alias el mexicano”, trasmitidas por los canales privados colombianos Caracol y RCN, respectivamente. A este material se le aplicó análisis de contenido, se seleccionaron los personajes femeninos y se clasificaron según su ocupación y características en cada autonomía (Toma de decisiones, Física y Económica).&#x0D; Resultados: en la narcoserie “El cartel de los sapos I”, la mayoría de las mujeres figuran con “ninguna ocupación”, son principalmente familiares de narcotraficantes y no existe un notorio prototipo de belleza; en “Alias el mexicano”, las mujeres, jóvenes y mayores, son usadas como “mulas” o correos humanos, son condenadas e intimidadas.&#x0D; Conclusiones: las narcoseries colombianas son narraciones audiovisuales carentes de mensaje de empoderamiento de autonomías en las mujeres, en los roles femeninos que incorporan en sus tramas.

Developing a micro-simulation tool for autonomous connected vehicle platoons used in city logistics

Abstract The future holds great promise for the use of autonomous vehicles. Many daily activities which require the use of extensive manpower, will soon be performed with much less human interference, if at all. City logistics is an example of one such arena, which will most surely benefit from the introduction of autonomous vehicles. Autonomous vehicles will replace human couriers in the near future, and conduct delivery tasks. Given the current trends in the freight industry, this will probably be integrated with the use of platoons, which has recently gained an increasing interest in the freight sector. In this paper we present an urban freight delivery system, which is based on the use of autonomous connected platoons. In the presented system, autonomous vehicles carry out delivery tasks, traveling from an origin depot to a customer, by joining platoons along the way, which bring them closer to their destination. Many issues can be analysed with respect to the proposed system. In this paper, we choose to focus on the travel time issue. In particular, we examine the effects different platoon configurations (total number of platoons in the network and their size) have on the travel time of the vehicles performing the delivery tasks. In order to examine the proposed system, a traffic microsimulation is used. A case study is presented, demonstrating the effects of varying the platoon number and size on the travel time. The results show a relation between the configuration of platoons and the travel time, especially with respect to the delay in intersections, and the waiting time while switching platoons.

Evaluation of the pneumatic tube system for transportation of packed red cell units.

Background:Pneumatic tube system (PTS) is commonly used in hospital settings to transport blood samples to diagnostic laboratories. At our blood center, we receive blood requisitions via the PTS, but units are carried to the ward by human courier. Recently we considered using the PTS for transporting blood units. Since, there are reports of hemolysis in blood samples sent through the PTS, we evaluated this system for transporting red cell units.Aims:The aim was to assess the effect of PTS transport on the quality of packed red cell units.Materials and Methods:A total of 50 red blood cells units (RBC), (25 non-irradiated and 25 irradiated) were subjected to transportation through the PTS. The control arm in the study was age-matched RBC units not subjected to PTS transport. Each RBC unit was evaluated for hemoglobin (Hb), lactate dehydrogenase, potassium and plasma hemoglobin (Hb). The paired t-test was used to compare these parameters, and the P value was calculated.Results and Conclusion:The percentage of hemolysis after transportation through PTS was below the recommended guidelines. Delivery of the blood unit to the wrong station, bags lying unattended at the destination were few of the problems that had to be addressed. To conclude, though the PTS is a safe means of transporting blood products with reduction in the turn-around-time, it must be validated before use.

Speed of sample transportation by a pneumatic tube system can influence the degree of hemolysis

The objective of the study was to find the incidence of hemolysis in samples transported through a pneumatic tube system (PTS) at different speeds. This prospective observational study was done in three phases: "short distance and high speed (115 m at 3 m/s)", "long distance and high speed (225 m at 3 m/s)" and "short distance and slow speed (115 at 2 m/s)". Fifty-two, 215 and 45 serum tube pairs, respectively, were evaluated in these three phases. A set of tubes was sent by PTS while the other was hand-carried. Samples were analyzed for supernatant hemoglobin (Hb), potassium (K+) and lactate dehydrogenase (LD). Mean transit time of samples through the PTS was much shorter as compared to human courier in all three phases. LD was elevated in PTS arm in the "short distance and high speed" phase and in the "long distance and high speed" phase, all three indices of hemolysis - Hb, K+ and LD - showed elevation in the PTS arm. However, at "short distance and slow speed" phase, there was no hemolysis in the PTS arm. Hospitals should validate their PTS before use and, by altering speed of sample transportation, hemolysis may be obliterated.

Agreement between paired blood gas values in samples transported either by a pneumatic system or by human courier

Rapid accurate assessment of metabolic derangements is crucial in the critically ill. We evaluated if arterial blood gas (ABG) samples transported through a pneumatic tube system (PTS) agreed with values transported by a human courier. In this prospective study of 50-paired ABG samples, the couriered reference ABG was compared with those transported by PTS. Agreement was summarised by the mean difference with 95% limits of agreement (LOA) and Lin's concordance correlation (pc). The mean (±SD) time from sampling to analysis was 35.7±23.2 (courier) and 38.6±22.1 (PTS) minutes. Agreement was good between courier and PTS for pH, PaCO(2), bicarbonate, oxygen saturation and PaO(2) values (pc>0.97). Although the mean difference in PaO(2) values between PTS and courier was small (-0.9 mm Hg) and the agreement was good, individual differences were clinically significant (95% LOA -40.8 to 39.0). For PaO(2) <160 mm Hg, analysis of PTS samples yielded erroneously high PaO(2) values and vice versa for PaO(2)>160 mm Hg compared to manual courier. This suggested exaggerated oxygen movement between the blood sample and air in the PTS. In this study, analysis of samples transported through the PTS resulted in clinically unacceptable PaO(2) values. Delay in transport and analysis of ABG samples should be avoided and samples transported manually if they cannot be assessed on-site.

Pneumatic Tube Delivery System for Blood Samples Reduces Turnaround Times Without Affecting Sample Quality

In this study, blood samples from ED patients that were delivered to the laboratory by a pneumatic tube delivery system and by a human courier were compared for timeliness and quality of results. We studied all consecutive measurements of serum hemoglobin and potassium ordered from 2 emergency departments of a multisite tertiary care hospital system, one with a pneumatic tube system and the other using human couriers. Turnaround time was measured from the time that the test was ordered by the physician to the time the result was reported on the hospital information system. Hemolysis was measured with use of a standardized, validated method. Times were normalized by log transformation (ln [minutes + 1]), and a comparison of sites was conducted using analysis of variance. Hemolysis rates of the 2 delivery systems were compared by chi2. There was no significant difference in hemolysis rate between the 2 methods of delivery (7/121 [5.79%] with a pneumatic tube system and 20/200 [10%] with a human courier). When delivered with a pneumatic tube system, the mean turnaround times (with ranges) for both hemoglobin (33 minutes [4-230]) and potassium (64 [34-208]) were shorter than those delivered by a human courier (43 minutes [3-150] and 72 [28-213], respectively). The use of a pneumatic tube delivery system for transporting blood samples from the emergency department to the laboratory can significantly reduce the turnaround times of results without a reduction in sample quality.

Simulation of robotic courier deliveries in hospital distribution services.

Flexible automation in the form of robotic couriers holds the potential for decreasing operating costs while improving delivery performance in hospital delivery systems. This paper discusses the use of simulation modeling to analyze the costs, benefits, and performance tradeoffs related to the installation and use of a fleet of robotic couriers within hospital facilities. The results of this study enable a better understanding of the delivery and transportation requirements of hospitals. Specifically, we examine how a fleet of robotic couriers can meet the performance requirements of the system while maintaining cost efficiency. We show that for clinical laboratory and pharmaceutical deliveries a fleet of six robotic couriers can achieve significant performance gains in terms of turn-around time and delivery variability over the current system of three human couriers per shift or 13 FTEs. Specifically, the simulation results indicate that using robotic couriers to perform both clinical laboratory and pharmaceutical deliveries would result in a 34% decrease in turn-around time, and a 38% decrease in delivery variability. In addition, a break-even analysis indicated that a positive net present value occurs if nine or more FTEs are eliminated with a resulting ROI of 12%. This analysis demonstrates that simulation can be a valuable tool for examining health care distribution services and indicates that a robotic courier system may yield significant benefits over a traditional courier system in this application.