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To study the anatomical features and classification of the angle between the right gastroepiploic vein (RGEV) and superior mesenteric vein/portal vein (SMV/PV) and to guide the catheterization of intraportal infusion chemotherapy through RGEV and reduce surgical complications.A retrospective three-dimensional (3D) computed tomography study was undertaken on 200 consecutive subjects with or without hepatic malignant tumors with a dedicated workstation 3D-MIA (the improved MI-3DVS workstation) developed by ourselves to determine the prevalence of surgically significant angle between RGEV and SMV/PV anatomic variations and its classification.The mean value of the angles between the end of RGEV and SMV/PV (AERS/P) (200 cases) was 84.2° ± 23.8 (31.4°-151.5°): 40.6° ± 92.3 (-177.9° to 178.0°) (sagittal angle), 81.7° ± 29.8 (-79.3° to 160.7°) (coronal angle), and 10.5° ± 94.3 (-178.7° to 175.8°) (horizontal angle). The mean value of the angles between the right bend of RGEV and SMV/PV (ARRS/P) (168 cases) was 104.8° ± 26.1 (20.5°-159.7°):49.3° ± 117.8 (-175.3° to 179.5°) (sagittal angle), 103.5° ± 37.7 (-178.8° to 168.9°) (coronal angle), and 12.6° ± 102.8 (-179.9° to 179.2°) (horizontal angle). The AERS/P were classified into large angle group (32 cases, 16%), middle angle group (113 cases, 56.5%), and small angle group (55 cases, 27.5%) based on angle variations and risks of catheterization.Precognition of the variations of AERS/P and ARRS/P before surgery is useful during chemotherapy pump catheterizing through RGEV in reduction of surgical complications by modulating the angle and direction of RGEV running into SMV/PV properly.

Numerous investigations on procalcitonin (PCT) have been carried out, although few with large sample size. To deal with the complexity of sepsis, an understanding of PCT in heterogeneous clinical conditions is required.Hospitalized patients aged 10-79 years were included in this retrospective and cross-sectional study. PCT tests were assayed within 2 days of blood culture.A total of 2952 cases (from 2538 patients) were enrolled in this study, including 440 cases in the 'positive BC' group, 123 cases in the 'positive body fluid culture' group, and 2389 cases in the 'negative all culture' group. Median PCT values were 4.53 ng/ml, 2.95 ng/ml, and 0.49 ng/ml, respectively. Median PCT values in the gram-negative BC group and gram-positive BC group, respectively, were 6.99 ng/ml and 2.96 ng/ml. Median PCT values in the 'positive hydrothorax culture' group, 'positive ascites culture' group, 'positive bile culture' group, and 'positive cerebrospinal fluid culture' group, respectively, were 1.39 ng/ml, 8.32 ng/ml, 5.98 ng/ml, and 0.46 ng/ml. In all, 357 cases were classified into the 'sepsis' group, 150 of them were classified into the 'severe sepsis' group. Median PCT values were 5.63 ng/ml and 11.06 ng/ml, respectively.PCT could be used in clinical algorithms to diagnose positive infections and sepsis. Different PCT levels could be related to different kinds of microbemia, different infection sites, and differing severity of sepsis.

In this study, a kind of uncertain network design problem, network design problem under uncertain construction cost, is researched.The discrete network design problem under uncertain construction costs deals with the selection of links to be added to the existing network, so as to minimize the total travel costs in the network. It is assumed that the value of the demand between each pair of origin and destination is a constant and the construction costs of each potential link addition follow a certain stochastic distribution. In this paper, a bi-level and stochastic programming model for the discrete network design problem is proposed. The construction costs of potential links are assumed as random variables and mutually independent with each other in this model. The upper-level model is a chance constrain model with the objective function of minimizing the total travel costs in the network, and the lower-level model is a user equilibrium model. The stochastic model is then transformed into a deterministic one. A branch-and-bound solution algorithm is designed to solve the deterministic model in an efficient way. At last, a computational experiment is conducted to illustrate the effectiveness and efficiency of the approach proposed in this paper. The results show that the stochastic model is more flexible and practical compared with the deterministic one.

The berth and quay crane in port are scarce resources. The scheduling optimization of them affects the ship's operating costs directly. In this paper we build an integration optimization model of berth allocation and quay crane scheduling to minimize the operating costs of quay crane and operating costs of the ships. A new genetic and ant colony algorithm is designed to solve this model.

In this paper, the continuous transportation network design problem with demand and cost uncertainties is studied while the generated trip between each origin-destination pair is deterministic. The paper will propose a bi-level uncertain model with robust optimizations. In the upper-level problem, the costs of expansion are uncertain by adding random variables to the cost function coefficients. Every random variable belongs to [0,1]. In the lower-level problem, the demand between each origin-destination pair is uncertain and belongs to a bounded interval and an ellipsoid. Then apply a genetic algorithm combined with the Frank-Wolfe algorithm to solve the model. Numerical examples suggest that the robust model with uncertain data has the advantage of operability and stability over the deterministic model.

In order to improve the emergency operation management system of the Gas Group, this paper deeply analyzed the process of urban gas repair operation, and put forward the method to determine the key factors of repair work. Through constructing the hierarchy structure model of gas repair operation characteristic factors, and using AHP algorithm to determine the weight of each characteristic factor, we find out the key factors of the repair operation. This method in grasping the key link in the operation, strengthening the training of key workers and improving the level of operation has important significance.

This paper discusses the fundamental framework of simulation system based on a super-microscopic simulation software, named Commuter. A large amount of field data of passengers in terminals is collected, and with these data a series of passenger parameters in the simulation models are calibrated. It is shown that the calibrated models are much more realistic in the phenomenon of passenger gathering, passing and dissipating, and quantitative indices reveal the necessity of the parameters calibration of passenger simulation models in terminals.