Advanced Storage and Retrieval Policies in Automated Warehouses

Warehouses are key components in supply chain. They facilitate the product flow from production to distribution. The performance of supply chains relies on the performance of warehouses and distribution centers. Being able to realize short order delivery lead times, in retail and ecommerce particularly, is important for warehouses. Efficient and responsive storage and retrieval operations can help in realizing a short order delivery lead time. Additionally, space scarcity has brought some companies to use high-density storage systems that increase space usage in the warehouse. In such storage systems, most of the available space is used for storing products, as little space is needed for transporting loads. However, the throughput capacity of high-density storage systems is typically low. New robotic and automated technologies help warehouses to increase their throughput and responsiveness. Warehouses adapting such technologies require customized storage and retrieval policies fit for automated operations. This thesis studies storage and retrieval policies in warehouses using several common and emerging automated technologies

Using Hybrid Query Tree to Cope with Capture Effect in RFID Tag Identification

Tag collision is one of the important issues in RFID systems. Many algorithms were proposed to address this issue. One of these algorithms is Query Tree (QT) which is an effective method. In addition, RFID suffers from Capture Effect (CE). CE occurs when a reader identifies one tag in the presence of a collision. We consider this as a bad phenomenon for QT, because under CE reader will not identify all of collided tags. Besides, CE is good phenomenon for some algorithms like Dynamic Framed Slotted Aloha (DFSA), because it can identify one tag even in collision slots. So we combine QT and DFSA to improve the QT performance, then we evaluate our proposed algorithm, called Hybrid QT, to show that it outperforms other similar algorithm

(2,2′-Bipyridine)(pyridine-2,6-dicarboxyl­ato)oxidovanadium(IV) ethanol monosolvate

In the title compound, [V(C7H3NO4)O(C10H8N2)]·C2H5OH, the VIV atom exhibits a distorted octa­hedral coordination environment formed by two pyridyl N atoms of 2,2′-bipyridine (bpy), the vanadyl O atom, and two carboxyl­ate O atoms and one pyridyl N atom of the tridentate pyridine-2,6-dicarboxyl­ate (pydc2−) ligand. The pyridyl N atom of the pydc2− anion and one pyridyl N atom of bpy occupy the axial positions. O—H⋯O hydrogen bonds involving the ethanol solvent mol­ecule as donor and a carboxyl­ate O atom as acceptor atoms, as well as C—H⋯O hydrogen bonds, together with π–π stacking inter­actions between adjacent aromatic rings (average centroid–centroid distance = 3.577 Å), seem to be effective in the stabilization of the crystal packing, resulting in the formation of a three-dimensional structure

An algorithm for coupling multibranch in vitro experiment to numerical physiology simulation for a hybrid cardiovascular model

The hybrid cardiovascular modeling approach integrates an in vitro experiment with a computational lumped‐parameter simulation, enabling direct physical testing of medical devices in the context of closed‐loop physiology. The interface between the in vitro and computational domains is essential for properly capturing the dynamic interactions of the two. To this end, we developed an iterative algorithm capable of coupling an in vitro experiment containing multiple branches to a lumped‐parameter physiology simulation. This algorithm identifies the unique flow waveform solution for each branch of the experiment using an iterative Broyden\u27s approach. For the purpose of algorithm testing, we first used mathematical surrogates to represent the in vitro experiments and demonstrated five scenarios where the in vitro surrogates are coupled to the computational physiology of a Fontan patient. This testing approach allows validation of the coupling result accuracy as the mathematical surrogates can be directly integrated into the computational simulation to obtain the “true solution” of the coupled system. Our algorithm successfully identified the solution flow waveforms in all test scenarios with results matching the true solutions with high accuracy. In all test cases, the number of iterations to achieve the desired convergence criteria was less than 130. To emulate realistic in vitro experiments in which noise contaminates the measurements, we perturbed the surrogate models by adding random noise. The convergence tolerance achievable with the coupling algorithm remained below the magnitudes of the added noise in all cases. Finally, we used this algorithm to couple a physical experiment to the computational physiology model to demonstrate its real‐world applicability

2-Amino­pyrimidinium hydrogen oxalate monohydrate

In the title hydrated salt, C4H6N3 +·C2HO4 −·H2O, inter­molecular N—H⋯O and O—H⋯O hydrogen bonding helps to stabilize the crystal structure

Paleomagnetic results from Upper Triassic and Middle Jurassic strata of east-central New Mexico, and implication for North American APWP

Two contradictory apparent polar wander paths (APWPs) of North America (NA) for most of Jurassic time have been the subject of many studies since the 1990s, and are important to rectify if in order to constrain the tectonic evolution of the continent. Among various efforts to resolve this persistent issue, additional results from well-dated kimberlite volcanics have been used to support a higher-latitude APWP (Kent et al., 2015), and the controversy was blamed on inclination error (IE) in paleomagnetic results of sedimentary units, most of which are from the U.S. South Western interior. Those paleomagnetic poles define the other, lower-latitude path (Kent and Irving, 2010). Here we present paleomagnetic results from Upper Triassic (Garita Creek, Trujillo, and Redonda Formations) and Middle Jurassic (Entrada, Summerville, and Lower Morrison Formations) sedimentary units of east-central New Mexico, which have magnetostratigraphy that can be correlated with geomagnetic polarity time scales (GPTSs). Positive reversal and fold tests confirm the primary magnetization in these units, which is mostly carried by detrital hematite. Interpretation of noisy and non-linear demagnetization paths, especially ones from Middle Jurassic units, was facilitated by a smoothing scheme, which did not bias the line and great circle fits. The less-than-ideal quality of the Middle Jurassic data could be due to the high rate of polarity reversals for this time period. As a side effect, the frequent usage of the great-circle fits to demagnetization paths was inevitable. We used the sample-level directions from the line fits to estimate the IE using the elongation/inclination (E/I) method of Tauxe and Kent (2004). IE for the Upper Triassic units is negligible because mean directions are horizontal. IE estimated for the Middle Jurassic units is ~20°, however with large 95% confidence limits. Paleomagnetic poles for Trujillo, Redonda, Summerville, and Lower Morrison Formations of east-central New Mexico, even with IE-correction streak approximately along the 60° parallel (in present coordinates) for most of the Jurassic time, which validates the lower-latitude APWP. Regardless of the robustness of E/I results, the effects of different amounts of IE can be simply simulated. From existing ca. 163 Ma Summerville Formation paleomagnetic poles, new ones were simulated assuming a possible range of IE. These results show that no amount of the IE correction to the sedimentary results would produce poles consistent with the high-latitude APWP so some other explanation for the discrepancy is required

Bis(4-carb­oxy­pyridine-2-carboxyl­ato-κ2 N,O 2)copper(II) dimethyl sulfoxide disolvate

In the title complex, [Cu(C7H4NO4)2]·2C2H6OS, the CuII atom is situated on an inversion centre and is N,O-chelated by two monoanionic 4-carb­oxy­pyridine-2-carboxyl­ate ligands in a slightly distorted square-planar coordination geometry. The dimethyl sulfoxide solvent mol­ecules and CuII complex mol­ecules are linked by O—H⋯O hydrogen bonding. In addition, C—H⋯O contacts and π–π inter­actions [centroid–centroid distance = 3.590 (1) Å] occur

Comparison of the clinical competence of nurses working in two university hospitals in Iran

Hospitals are integrated with medical universities in Iran and are categorized into three types with respect to educational and health services quality. This cross-sectional study aimed to determine and compare the level of clinical competence of nurses who were working in type 1 and type 2 university hospitals. The clinical competence of all 266 nurses in the two hospitals was assessed by using the self-assessment method.The Nurse Competence Scale, a questionnaire consisting of 73 items, was used to assess the level of clinical competence and the frequency of using skills. The nurses who were working in the type 1 university hospital viewed themselves as more competent than those who were working in the type 2 university hospital. Also, only 70% of the clinical skills were used frequently by the nurses who were working in the type 2 university hospital, in comparison to > 83% for the nurses who were working in the type 1 university hospital.The results can be used for the educational needs assessment of nurses and for modifying the quality of care in hospitals