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It is a common practice to assign the return period of a given storm event to the urban pluvial flood event that such storm generates. However, this approach may be inappropriate as rainfall events with the same return period can produce different urban pluvial flooding events, i.e., with different associated flood extent, water levels and return periods. This depends on the characteristics of the rainfall events, such as spatial variability, and on other characteristics of the sewer system and the catchment. To address this, the paper presents an innovative contribution to produce stochastic urban pluvial flood hazard maps. A stochastic rainfall generator for urban-scale applications was employed to generate an ensemble of spatially—and temporally—variable design storms with similar return period. These were used as input to the urban drainage model of a pilot urban catchment (~9 km2) located in London, UK. Stochastic flood hazard maps were generated through a frequency analysis of the flooding generated by the various storm events. The stochastic flood hazard maps obtained show that rainfall spatial-temporal variability is an important factor in the estimation of flood likelihood in urban areas. Moreover, as compared to the flood hazard maps obtained by using a single spatially-uniform storm event, the stochastic maps generated in this study provide a more comprehensive assessment of flood hazard which enables better informed flood risk management decisions. ispartof: Water - Basel vol:7 issue:7 pages:3396-3406 status: published

BACKGROUND: Transbronchial needle aspiration (TBNA), serving as a remarkably invaluable and minimally invasive technique, has been widely used for the diagnosis and staging of mediastinal adenopathy and masses. To date, the International Association for the Study of Lung Cancer (IASLC) and Wang's nodal map are two well-documented intrathoracic lymph node guidelines for the TBNA procedure. METHOD: We characterized IASLC's and Wang's map, and interpreted the correlation of the two maps station by station. RESULTS: The pivotal role of IASLC map is to determine N descriptor in the tumor node metastasis (TNM) staging system of lung cancer, whilst Wang's map is employed to facilitate the localization of biopsy sites for bronchoscopists during TBNA performance. Furthermore, stations 1, 3 and 5 in Wang' map are equivalent to 4R station in IASLC' system, while stations 4 and 6 in Wang's account for IASLC station 4L as N2 stations. In addition, Wang's stations 2, 8 and 10 are correlated with station 7 in IASLC's. Wang's stations 7 and 9 are responsible for station 11R in IASLC's map. CONCLUSION: Given their unique benefits and limitations, and the practical links between the two maps, it appears reasonable to highlight the significance of their complementary utilization upon TBNA performance and lung cancer staging.

Background: The optimal method for EBUS-TBNA to maximize diagnostic accuracy and to minimize operational complexity is controversial.­ Aims: We conducted the randomized controlled clinical trial to evaluate the effects of suction and inner-stylet usage on EBUS-TBNA, the feasibility of omitting stylet, and the necessity of using suction. Methods: Consecutive patients with enlarged mediastinal and hilar lymph nodes (LNs) detected by imaging tests underwent EBUS-TBNA. Each LN was sampled three passes, randomly by with suction-with stylet, with suction-no stylet, and no suction-with stylet technique. A single, blinded cytopathologist respetively evaluated each set of cell slides. The primary outcome was diagnostic accuracy of different EBUS-TBNA techniques. The secondary outcomes were specimen adequacy, cytological quality, operational time and the amount of bleeding. Result: 43 patients with a total of 124 LNs were evaluated. The final diagnosis of patients was benign in 23, malignant in 20. The final diagnosis of LNs was benign in 83, malignant in 39, inadequate in 2. The use of stylet did not improve diagnosis accuracy and the use of suction did not decrease diagnosis accuracy (each P value >0.5). But the use of suction was associated with an increase in the specimen adequacy(P=0.000). Without-stylet technique significantly reduced operational time(P=0.000). There was no significant difference in the amount of bleeding, cytological quality between techniques. Conclusion: When EBUS-TBNA is necessary, our recommendation is eliminating stylet and applying suction to improve diagnostic accuracy and to reduce operational complexity.

Long waiting times in health evaluations are an unnecessary waste of resources. This case study focuses on the Health Evaluation Center in the Chang Gung Medical Center in Taiwan and demonstrates an empirical application of reducing waiting time by using the Design for Six Sigma method. We redesigned the health evaluation process and proposed a method to develop a new capable system with radio frequency identification (RFID) technology. Client waiting time and total cycle time of the process were reduced by 56% and 40%, respectively.

The cyclic scheduling for staffs in hospitals has been widely studied but none in the literature is about the nurse scheduling problem in the outpatient departments. Considering fairness and relevant constraints in scheduling outpatient nurses, this study formulates the nurse assignment problem as a binary goal programming model. An optimized and “fair” weekly schedule satisfying the stated hospital’s policies and the outpatient nurses’ preferences is solved. A “fair” schedule is in the sense that the number of due shifts and the shift patterns are assigned as same as possible for all the full-time nurses during the weekdays. A sensitivity analysis on the number of full-time nurses is also performed to answer the question about the best utilization in scheduling nurses. This study replaces the manual-made schedule with a computerized one and provides hospital managers insights in identifying the best human-resource portfolio in outpatient nurse scheduling.

Proponents of the endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) propose that in this era of EBUS-TBNA, training for conventional transbronchial needle aspiration (C-TBNA) should be abandoned. The authors of this editorial provide the opposing view. C-TBNA has a short and a steep learning curve and adds to the diagnostic yield of flexible bronchoscopy in a cost-effective fashion. Considering its simplicity, availability, affordability, safety, and several unique indications, C-TBNA continues to contribute to the welfare of patients worldwide. It should remain as an integral part of pulmonary fellowship training programs.

The applicability of the operational radar and raingauge networks for urban hydrology is insufficient. Radar rainfall estimates provide a good description of the spatiotemporal variability of rainfall; however, their accuracy is in general insufficient. It is therefore necessary to adjust radar measurements using raingauge data, which provide accurate point rainfall information. Several gauge-based radar rainfall adjustment techniques have been developed and mainly applied at coarser spatial and temporal scales; however, their suitability for small-scale urban hydrology is seldom explored. In this paper a review of gauge-based adjustment techniques is first provided. After that, two techniques, respectively based upon the ideas of mean bias reduction and error variance minimisation, were selected and tested using as case study an urban catchment (∼8.65 km2) in North-East London. The radar rainfall estimates of four historical events (2010–2012) were adjusted using in situ raingauge estimates and the adjusted rainfall fields were applied to the hydraulic model of the study area. The results show that both techniques can effectively reduce mean bias; however, the technique based upon error variance minimisation can in general better reproduce the spatial and temporal variability of rainfall, which proved to have a significant impact on the subsequent hydraulic outputs. This suggests that error variance minimisation based methods may be more appropriate for urban-scale hydrological applications.

In a vertically integrated supply chain of healthcare groups such as Chang Gung memorial hospitals in Taiwan, the vendor of special medical items and the hospitals are owned by the same business conglomerate; besides, warehouse capacity is one of the scarcest resources that greatly affect the inventory control policies. Taking the vendor’s limited warehouse capacity into account, this article first proposes a generic joint economic lot sizing (JELS) model in determining the optimal production and shipment policy for a two-layer supply chain. The vendor manufactures the requested products in lots and delivers them in batches to the buyer with partial shipment policy. A threshold value which defines those existing JELS problems as a special case of our proposed model, while the manufacturer’s warehouse capacity exceeds it, is attained. Finally, a numerical example is used to characterize the optimal production and replenishment lot-size decisions for the supply chain.

Fractal analysis relies on scale invariance and the concept of fractal dimension enables one to characterize and quantify the space filled by a geometrical set exhibiting complex and tortuous patterns. Fractal tools have been widely used in hydrology but seldom in the specific context of urban hydrology. In this paper, fractal tools are used to analyse surface and sewer data from 10 urban or peri-urban catchments located in five European countries. The aim was to characterize urban catchment properties accounting for the complexity and inhomogeneity typical of urban water systems. Sewer system density and imperviousness (roads or buildings), represented in rasterized maps of 2 m × 2 m pixels, were analysed to quantify their fractal dimension, characteristic of scaling invariance. The results showed that both sewer density and imperviousness exhibit scale-invariant features and can be characterized with the help of fractal dimensions ranging from 1.6 to 2, depending on the catchment. In a given area consistent results were found for the two geometrical features, yielding a robust and innovative way of quantifying the level of urbanization. The representation of imperviousness in operational semi-distributed hydrological models for these catchments was also investigated by computing fractal dimensions of the geometrical sets made up of the sub-catchments with coefficients of imperviousness greater than a range of thresholds. It enables one to quantify how well spatial structures of imperviousness were represented in the urban hydrological models. Interreg IVB NWE project RainGain ispartof: Hydrology and Earth System Sciences vol:21 issue:5 pages:2361-2375 status: published

The invaluable role of transbronchial needle aspiration (TBNA) in the diagnosis and staging of mediastinal adenopathy and lung cancer has been well established. Different lymph nodes regional nomenclatures and maps had been described over the years. The international association for the study of lung cancer (IASLC) and Wang’s maps complement each other benefiting patients with lung cancer. In this article we briefly reviewed the roles of IALSC, Wang’s maps and ROSE in TBNA.

Pulmonary nodules remain a diagnostic challenge for physicians. Minimally invasive biopsy methods include bronchoscopy and CT guided transthoracic needle aspiration (TTNA). A novel electromagnetic guidance transthoracic needle aspiration (ETTNA) procedure which can be combined with navigational bronchoscopy (NB) and endobronchial ultrasound (EBUS) in a single setting has become available.A prospective pilot study examining the safety, feasibility and diagnostic yield of ETTNA in a single procedural setting. All patients enrolled underwent EBUS for lung cancer staging followed by NB and ETTNA. Feasibility of performing ETTNA and a safety assessment by recording procedural related complications including pneumothorax or bleeding was performed. Diagnostic yield of ETTNA defined by a definitive pathologic tissue diagnosis was recorded. An additional diagnostic yield analysis was performed using a cohort analysis of combined interventions (EBUS + NB + ETTNA). All non-diagnostic biopsies were either followed with radiographic imaging or a surgical biopsy was performed.Twenty-four subjects were enrolled. ETTNA was feasible in 96% of cases. No bleeding events occurred. There were five pneumothoraces (21%) of which only two (8%) subjects required drainage. The diagnostic yield for ETTNA alone was 83% and increased to 87% (P=0.0016) when ETTNA was combined with NB. When ETTNA and NB were performed with EBUS for complete staging, the diagnostic yield increased further to 92% (P=0.0001).This is the first human pilot study demonstrating an acceptable safety and feasibility profile with a novel ETTNA system. Further studies are needed to investigate the increased diagnostic yield from this pilot study.

Lung cancer is the leading cause of malignant-tumor-related morbidity and mortality worldwide. Transbronchial needle aspiration (TBNA) has for the past 30 years been an effective technique for the diagnosis and staging of lung cancer. Understanding the anatomy of mediastinal and hilar lymph nodes is essential to improve the yield of TBNA. Wang’s lymph node map is based on the lymph node map of the American Thoracic Society (ATS), and on the TBNA technique; it was published in 1994, and has promoted the development of both conventional TBNA (cTBNA) and endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA). In 2009, the International Association for the Study of Lung Cancer (IASLC) developed a new chest lymph node map to reconcile the differences between the Naruke and The Mountain-Dresler (MD)-ATS lymph node maps. The IASLC lymph node map was incorporated into the seventh edition of the tumor, node, metastasis (TNM) staging system for lung cancer, which directly affected the treatment and prognosis of lung cancer. There are significant differences between Wang’s lymph node map and the IASLC lymph node map in TNM staging, and it is imperative to understand these differences and correlate these maps for the prognosis and staging of lung cancer using cTBNA or EBUS-TBNA.

Over the last decade, the increasing diffusion of innovative and more powerful imaging guided techniques has further broadened the bronchoscopist’s horizons in the diagnostic work-up of peripheral pulmonary nodules/masses (PPN/M). However, in most of institutions worldwide, due to the lack of resources and specific skills, the routinely diagnostic approach to PPN/M is still represented by imaging-guided transbronchial needle aspirations (TBNA) and percutaneous needle aspirations (PCNA). So far, no randomized clinical trials directly comparing the accuracy of the two procedures are available, and a standardized strategy that defines the proper role of each technique has yet to be established. In fact, the choice between these procedures is mostly influenced by “environmental” factors, such as operator’s experience and local resources, rather than by an established algorithm, based on selected clinical scenarios. Data from literature indirectly suggest a higher sensitivity of PCNA compared to transbronchial approach, especially when lesions are peripheral and less than 2 cm. On the other hand, the transbronchial approach has been shown to have a better safety profile. Moreover, it offers the advantages to provide, during a single examination, a pathological diagnosis of nodules, information on mediastinal staging and airways involvement, and to identify potential synchronous lesions. In this context, it would be reasonable to firstly perform flexible bronchoscopy with TBNA, and, in case of inconclusive results, PCNA. In conclusions, both the techniques have been shown to be useful in the diagnostic pre-operative work-up of PPN/M. In order to optimize the diagnostic yield and to minimize the risk of patients they should not to be considered as two alternative options, but, rather, as two complementary techniques integrated in a standardized algorithm.

Conventional transbronchial needle aspiration (cTBNA) was first performed approximately 30 years ago; however TBNA was not widely adopted until the development of endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA). Current EBUS-TBNA needle sizes are limited to 21- and 22-gauge. In order to determine whether a 19-gauge (19G) needle in EBUS-TBNA can further improve the diagnostic yield and simplify the methodology of EBUS-TBNA we developed a hybrid method. Here we report our initial experience in assessing the feasibility of performing EBUS-TBNA using a conventional 19G TBNA needle.Ten patients with diagnosed or suspected lung cancer with or without lymphadenopathy (LAD) were sampled for diagnostic and/or staging purposes. Patients with suspected benign processes were sampled only for diagnosis. A 19G cTBNA needle was deployed through the working channel of the EBUS bronchoscope. Samples obtained were evaluated for cyto- and histopathologic adequacy.All 10 patients successfully underwent hybrid 19G EBUS-TBNA. All samples were considered adequate for cyto- and histopathologic evaluation.Hybrid EBUS-TBNA utilizing a 19G cTBNA needle through an EBUS scope is feasible and may be able to reliably acquire histologic specimens.

Location selection significantly influences business success. In particular, location selection for the fuel stations is characterized by constraints on investment in facilities and by criteria that involve a series of social utilities. Recently, a leading fuel company in Taiwan initiated transforming its traditional gas stations into self-service. However, it is difficult to select an existing station to be transformed as self-service because there are many conflicting goals in the problem of location selection. In this paper, we apply a multicriteria approach, integrating analytic hierarchy process (AHP) and multichoice goal programming (MCGP), to obtain an appropriate gas station from many alternative locations that best suit the preferences of decision-makers in the case company. This study incorporates the weights obtained from AHP to set multiple aspirations in MCGP for ranking each candidate location. The results show that, under multiple quantitative and qualitative factors in the selection process, our proposed model is more scientific and efficient than unaided methods in finding a suitable location within a shorter evaluation time.

This paper presents an approach to enhance the role of local stakeholders in dealing with urban floods. The concept is based on the DIANE-CM project (Decentralised Integrated Analysis and Enhancement of Awareness through Collaborative Modelling and Management of Flood Risk) of the 2nd ERANET CRUE funding initiative. The main objective of the project was to develop and test an advanced methodology for enhancing the resilience of local communities to flooding. Through collaborative modelling, a social learning process was initiated that enhances the social capacity of the stakeholders due to the interaction process. The other aim of the project was to better understand how data from hazard and vulnerability analyses and improved maps, as well as from the near real-time flood prediction, can be used to initiate a public dialogue (i.e. collaborative mapping and planning activities) in order to carry out more informed and shared decision-making processes and to enhance flood risk awareness. The concept of collaborative modelling was applied in two case studies: (1) the Cranbrook catchment in the UK, with focus on pluvial flooding; and (2) the Alster catchment in Germany, with focus on fluvial flooding. As a result of the interactive and social learning process, supported by sociotechnical instruments, an understanding of flood risk was developed amongst the stakeholders and alternatives for flood risk management for the respective case study area were jointly developed and ranked as a basis for further planning and management.

Endobronchial ultrasound transbronchial needle aspiration (EBUS-TBNA) has revolutionized the evaluation of patients with mediastinal and hilar adenopathy. Limitations of conventional endobronchial ultrasound (C-EBUS) bronchoscopes include the inability to perform a complete airway inspection, low definition optics, and limited maneuverability. These limitations require the use of a standard bronchoscope to perform an airway examination prior to the EBUS procedure. Recently, a hybrid endobronchial ultrasound (H-EBUS) bronchoscope with high definition optics and increased maneuverability has been introduced. Our objective was to assess the ability of H-EBUS to perform a full airway inspection and TBNA.Patients referred for EBUS-TBNA were prospectively randomized to either form of EBUS from November 2013 to January 2014. The primary outcome was the airway segment visualization in each lobe using an EBUS bronchoscope. Secondary outcomes included the number of bronchoscopes used per procedure, procedure length, diagnostic yield and specimen adequacy.Sixty-two consecutive patients undergoing EBUS-TBNA were randomized to H-EBUS (n=30) or C-EBUS (n=32). In cases in which EBUS-TBNA was the only procedure performed (n=32), use of a second bronchoscope to perform an adequate airway inspection was significantly higher in C-EBUS compared to H-EBUS (5 vs. 0, P=0.046). There was better segmental visualization achieved in multiple lobes when using H-EBUS (P0.01). No differences in TBNA sample diagnostic yield, specimen adequacy or procedure time were noted when comparing bronchoscopes (P= NS).Use of an H-EBUS may improve the ability to perform an adequate airway inspection potentially obviating the need for a conventional bronchoscope.

Transbronchial needle aspiration (TBNA) has been used for over three decades in the diagnosis and staging of mediastinal adenopathy and masses. Although first described in Argentina in 1949 by Dr. Eduardo Schieppati, this rigid bronchoscope technique received very little attention until 1978 at Johns Hopkins Hospital where Wang and colleagues described in detail the diagnosis of a paratracheal mass by TBNA biopsy through a rigid bronchoscope using a 25-gauge esophageal variceal needle. In 1983, a novel flexible needle that could be used with the flexible bronchoscope to perform TBNA was developed and introduced for diagnosis and staging of bronchogenic carcinoma. Immediately to follow was the expansion of its use in the diagnosis of peripheral pulmonary nodules and benign mediastinum and hilar disorders by obtaining histological core specimens. Recent development of the endobronchial ultrasound-guided TBNA is most exciting and promising. Whether this will enhance the result of TBNA and spread the TBNA technique as a standard lung cancer staging procedure is yet to be seen. TBNA is simpler and easier. Endobronchial ultrasound-guided TBNA currently is more complicated and more difficult. Its future relies on a hybrid instrument and methodology to be widely applied to the diagnosis and staging of bronchogenic carcinoma.

Previous research on the joint economic lot size (JELS) problem was focused on the decisions of lot sizes and batches delivered among players in the supply chain, assuming that transportation cost was independent of shipment amounts. Nevertheless, the transportation cost accounts for a major part of supply chain cost, especially when transportation companies offer freight rate discount schedules to the supply channel, shippers are able to claim over-declared shipment to lower their transportation costs. The impact of freight rate discount is significant and should not be overlooked. In this article, we address an integrated three-level JELS problem with freight rate discounts. Managerial insights of the model are illustrated in propositions and numerical examples are provided.

Most of the coal reservoirs in China are of low-permeability, so hydraulic fracturing is widely used to improve the permeability in the extraction of gas by ground drilling. The ground stress around the well was analyzed by using theory of elasticity. The pressure when the well fractured is formulated and the effect of ground stress on pressure is discussed. The effect of ground-stress-differences on hydraulic fracturing was analyzed by using the numerical software RFPA 2D -Flow in reference to the tectonic stress in Jincheng coal area. The results show that: 1) the position where initial fracture appears is random and fracture branches emerge when the fractures expand if ground stresses in any two directions within a horizontal plane are equal; 2) otherwise, the fractures expand in general along the direction of maximum ground stress and the critical pressure decreases with increasing ground-stress-differences and 3) the preferred well-disposition pattern is diamond shaped. The preferred well spacing is 250 m × 300 m. This study can provide a reference for the design of wells.

Summary Rainfall estimates of the highest possible accuracy and resolution are required for urban hydrological applications, given the small size and fast response which characterise urban catchments. While radar rainfall estimates have the advantage of well capturing the spatial structure of rainfall fields and its variation in time, the commonly available radar rainfall products (typically at ∼1 km/5–10 min resolution) may still fail to satisfy the accuracy and resolution – in particular temporal resolution – requirements of urban hydrology. A methodology is proposed in this paper, to produce higher temporal resolution, more accurate radar rainfall estimates, suitable for urban hydrological applications. The proposed methodology entails two main steps: (1) Temporal interpolation of radar images from the originally-available temporal resolutions (i.e. 5–10 min) to finer resolutions at which local rain gauge data are commonly available (i.e. 1–2 min). This is done using a novel interpolation technique, based upon the multi-scale variational optical flow technique, and which can well capture the small-scale rainfall structures relevant at urban scales. (2) Local and dynamic gauge-based adjustment of the higher temporal resolution radar rainfall estimates is performed afterwards, by means of the Bayesian data merging method. The proposed methodology is tested using as case study a total of 8 storm events observed in the Cranbrook (UK) and Herent (BE) urban catchments, for which radar rainfall estimates, local rain gauge and depth/flow records, as well as recently calibrated urban drainage models were available. The results suggest that the proposed methodology can provide significantly improved radar rainfall estimates and thereby generate more accurate runoff simulations at urban scales, over and above the benefits derived from the mere application of Bayesian merging at the original temporal resolution at which radar estimates are available. The benefits of the proposed temporal interpolation + merging methodology are particularly evident in storm events with strong and fast-changing (convective-like) rain cells.

This study compares two nonparametric rainfall data merging methods—the mean bias correction and double-kernel smoothing—with two geostatistical methods—kriging with external drift and Bayesian combination—for optimizing the hydrometeorological performance of a satellite-based precipitation product over a mesoscale tropical Andean watershed in Peru. The analysis is conducted using 11 years of daily time series from the Tropical Rainfall Measuring Mission (TRMM) Multisatellite Precipitation Analysis (TMPA) research product (also TRMM 3B42) and 173 rain gauges from the national weather station network. The results are assessed using 1) a cross-validation procedure and 2) a catchment water balance analysis and hydrological modeling. It is found that the double-kernel smoothing method delivered the most consistent improvement over the original satellite product in both the cross-validation and hydrological evaluation. The mean bias correction also improved hydrological performance scores, particularly at the subbasin scale where the rain gauge density is higher. Given the spatial heterogeneity of the climate, the size of the modeled catchment, and the sparsity of data, it is concluded that nonparametric merging methods can perform as well as or better than more complex geostatistical methods, whose assumptions may not hold under the studied conditions. Based on these results, a systematic approach to the selection of a satellite–rain gauge data merging technique is proposed that is based on data characteristics. Finally, the underperformance of an ordinary kriging interpolation of the rain gauge data, compared to TMPA and other merged products, supports the use of satellite-based products over gridded rain gauge products that utilize sparse data for hydrological modeling at large scales. ispartof: Journal of Hydrometeorology vol:16 issue:5 pages:2153-2168 status: published

A new device of air time–velocity variations in cool-thermal discharge systems from ice melting with complete melt removal was proposed and the mathematical formulation for calculating the outlet chilled air temperature with convective transfer by adjusting the air mass velocity on free ice surface was developed. The proposed device in this study is a technical feasibility in controlling the outlet chilled air temperature by adjusting the air mass velocity and enhancing heat transfer efficiency by removing melt with a maximum temperature gradient. Three numerical examples of the inlet ambient air temperature were illustrated for practical applications under complete melt removal, and hence the time history of the air mass velocity was also obtained for the desired outlet chilled air temperature. © 2003 Wiley Periodicals, Inc. Heat Trans Asian Res, 32(6): 524–532, 2003; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/htj/10119

It has long been assumed that the shortages in inventory systems are either completely backlogged or totally lost. However, it is more reasonable to characterize that the longer the waiting time for the next replenishment is, the smaller the backlogging rate would be. In this paper, we define an appropriate partial backlogging rate to make the present model general and realistic for deteriorating items with time-varying demand and we also consider the opportunity cost due to lost sales. We show that the optimal solution minimizing the total cost is exactly the one that maximizing the profit. In addition, we verify that the optimal replenishment policy still possesses the monotonicity properties. Moreover, to generate a good estimation of the first replenishment time, we provide a simple heuristic by considering a relation between the cost components in the first cycle.

A more efficient device in energy transfer for a cool thermal discharge system has been designed. The governing equations have been derived from ice melting with specified heat fluxes on the boundary of complete removal of melt, and the approximation solutions were obtained, from the integral boundary-layer analysis, to estimate the thickness of ice melted and the thermal penetration distance in the ice-layer region. Considerable improvement in performance of cool thermal discharge can be achieved if the operation is conducted with complete removal of melt, rather than without removal of melt.

We consider the optimal strategy for a gambler who is faced with a finite sequence of two-outcome games, i.e., “win” vs. “lose,” and wants to maximize the expected utility of his final wealth. Unli...

This article deals with the time histories of the air flow rate required and the temperature of chilled air produced during cooling of air by melting ice with specified heat flux at the free liquid surface. The equations for estimating the required mass flow rate of air to maintain a specified heat flux removal of cool thermal discharge by direct contact of air with melting ice to produce chilled air were derived from an analysis of the heat transfer coupled with the moving boundary. Numerical examples are illustrated in which the inlet air temperatures were either specified or varied with time to simulate practical systems.

Background Transbronchial needle aspiration (TBNA), serving as a remarkably invaluable and minimally invasive technique, has been widely used for the diagnosis and staging of mediastinal adenopathy and masses. To date, the International Association for the Study of Lung Cancer (IASLC) and Wang's nodal map are two well-documented intrathoracic lymph node guidelines for the TBNA procedure. Method We characterized IASLC's and Wang's map, and interpreted the correlation of the two maps station by station. Results The pivotal role of IASLC map is to determine N descriptor in the tumor node metastasis (TNM) staging system of lung cancer, whilst Wang's map is employed to facilitate the localization of biopsy sites for bronchoscopists during TBNA performance. Furthermore, stations 1, 3 and 5 in Wang’ map are equivalent to 4R station in IASLC’ system, while stations 4 and 6 in Wang's account for IASLC station 4L as N2 stations. In addition, Wang's stations 2, 8 and 10 are correlated with station 7 in IASLC's. Wang's stations 7 and 9 are responsible for station 11R in IASLC's map. Conclusion Given their unique benefits and limitations, and the practical links between the two maps, it appears reasonable to highlight the significance of their complementary utilization upon TBNA performance and lung cancer staging.

Study objectives: To compare two different imageregistration methods for accurately displaying the position of aflexible bronchoscope on a previously acquired three-dimensional CTscan during bronchoscopy. Setting: Bronchoscopy suiteof a university hospital. Patients: Fifteen adultpatients scheduled for nonemergent bronchoscopy. Methods: A miniature electromagnetic positionsensor was placed at the tip of a flexible bronchoscope. Previouslyacquired three-dimensional CT scans were registered with the patient inthe bronchoscopy suite. Registration method 1 used multiple skinfiducial markers. Registration method 2 used the inner surface of thetrachea itself for registration. Method 1 was objectively assessed bymeasuring the error distance between the real skin marker position andthe computer display position. Methods 1 and 2 were subjectivelyassessed by the bronchoscopist correlating visual bronchoscopicanatomic location with the computer display position on the CTimage. Results: The error distance (± SD) from knownpoints for registration method 1 was 5.6 ± 2.7 mm. Objective errordistances were not measured for method 2 because no accurate placementof the bronchoscope sensor could be correlated with CT position. Subjectively, method 2 was judged more accurate than method 1 whencompared with the fiberoptic view of the airways through thebronchoscope. Additionally, method 2 had the advantage of not requiringplacement of fiducial markers before the CT scan. Respiratory motioncontributed an error of 3.6 ± 2.6 mm, which was partially compensatedfor by a second tracking sensor placed on the patient’s chest. Conclusion: Image registration method 2 of surface fittingthe trachea rather than method 1 of fiducial markers was subjectivelyjudged to be superior for registering the position of a flexiblebronchoscope during bronchoscopy. Method 2 was also more practicalinasmuch as no special CT scanning technique was required beforebronchoscopy.

A new device of ice melting with performance improved has been developed by complete removal of melt to produce chilled air during on-peak power consumption. Energy equations have been derived, from the integral boundary-layer analysis, for estimating the thickness of the ice melted and the thermal penetration distance in ice layer region with convective boundary condition on free surface. Numerical examples have been illustrated in which the air temperature was specified and varied with time to simulate practical systems.Results show that complete removal of melt in cool-thermal discharge systems can enhance the flux of discharge due to heat transfer being much easier than that in the systems without removal of melt. Therefore, considerable improvement in performance of cool thermal discharge can be accomplished if the system is operating with rather than without complete removal of melt.

This article introduces a bivariate shape-preserving interpolation algorithm to approximate the value function of a dynamic program. First, we present a savings allocation problem between a pension account and another non-pension one. With the objective of maximizing the present value of utility over a life cycle, the investor can distribute his or her savings, in each account, between stocks and cash funds. Formally, this complex problem involved with various tax rules is in dynamic programming formulation and can only be solved numerically. It is known that the value function of the associated two-dimensional dynamic program inherits monotonicity and convexity of the investor's risk-averse utility function. To preserve these shape characteristics, we apply a bivariate shape-preserving interpolation algorithm in the successive approximation of the value function. Finally, we have computational results for this savings allocation problem, showing that the proposed shape-preserving interpolation method is superior to other dynamic programming methods with less sophisticated interpolation techniques. Scope and purpose The savings allocation problems with several dimensions of continuous states are too complicated and thus can only be solved by numerical dynamic programming. Theory of dynamic programming has shown that the associated value function inherits the shape characteristics – monotonicity and concavity – of a risk-averse investor's utility function. However, there are no numerical methods which guarantee to preserve these shape features in the course of approximation of the value function. In this article, we model a savings allocation problem as a two-dimensional dynamic program and we present a bivariate shape-preserving interpolation method to solve it.

The purpose of this study was to determine whether intravenous injection of a magnetic resonance (MR) contrast agent, ultrasmall superparamagnetic iron oxide (ferumoxtran-10), can be useful in characterizing lymph nodes in patients with lung cancer. Twelve patients with known or suspected lung cancer were studied. Pre- and postcontrast injection of ferumoxtran-10 MR scans of the chest were obtained. Analysis of the signal intensities and bronchoscopic fine needle aspiration of a single node were performed in each patient. Six of 12 patients had a final diagnosis of lung cancer. T1-weighted images were best for localizing mediastinal lymph nodes. Signal intensity changes before and after contrast were best visualized on T2-weighted and gradient-echo images. All four patients with lung cancer who had nodes positive for malignancy at biopsy had no change in signal intensity of the nodes on T2 images. The signal intensity decreased in the remaining two patients, and the nodes were benign. Of the eight patients with benign disease, five had no change in signal intensity of the nodes. Therefore the sensitivity for tumor involvement of the nodes is 100%, but the specificity is only 37.5%. Ferumoxtran-10 is a contrast agent that can alter the signal intensity of lymph nodes. Lack of signal change may be due to malignant or inflammatory change. Studies in a larger population of lung cancer patients may help to characterize the utility of this agent further. J. Magn. Reson. Imaging 2000;12:899–904. © 2000 Wiley-Liss, Inc.

Dieulafoy lesion (DL), also known as Cirsoid aneurysm, and submucosal arterial malformation was originally described by Gallard in 1884. In 1898, the French surgeon, Dieulafoy, reported 3 patients with hematemesis and gastric bleeding emanating from a submucosal vascular anomaly. Although DL is seen most commonly in the gastrointestinal tract, the presence of this lesion in the bronchus has been reported in 12 cases previously. In this report, we present the 13th reported case of hemoptysis resulting from bronchial DL, review the previously reported cases, and comment on the appropriate diagnostic and therapeutic strategy.

A model of ice melting has been developed to produce chilled air during on-peak power consumption. Equations have been derived for estimating the thickness of the melted ice and the temperature distribution in the liquid region with convection boundary condition. Three test cases have been studied in which the air temperature was specified and varied with time. Results are given for the thickness of the melted ice layers for cool thermal discharges. The cool thermal discharge and the penetration distance for ice melting, increase with air velocity, especially at low velocities of about 10 m/s; they decrease weakly as the length traversed by air increases.

With rapid estimate model, maternal mortality in China for the year of 1990 was estimated, where vital statistics system has not been well established. Since the original methodology failed to address the validity of estimate, the assessment was made by application of this method to the published figures in Japan from 1960 to 1990. The results manifested the model is good for the purpose of estimation when data of age-specific mortlity and fertility are available with limited registration failures. The maternal mortality rate in China, which was estimated with this model, was higher than that obtained in sampling survey of Chinese government. The multiple regression analysis suggested the sampling survey might fail to include maternal deaths from unplanned births.

The work presented here is a contribution to the Thames Water project of improving the Counters Creek catchment sewerage system in London. An increase in the number of floods affecting basements in the area has indicated the need for improvements to the system. The cost of such improvements could be very high, and as such it is important to determine whether the traditional approach of applying 30-year spatially uniform design storms results in substantial overestimation. The first step in this is to generate simulations of spatially distributed rainfall events, from which 30-year storms can be extracted. Storms are modelled as clusters of Gaussian rainfall cells, extending the earlier Willems method to radar rainfall data. The parameters describing the cells and their motion are sampled from probability distributions derived from parameter estimates gained from 45 historical storm events within the catchment for the period 2000–2011. This spatial-temporal stochastic rainfall generator produces a two-dimensional time series of simulated storm events, from which events of given return period can be identified.