Control quantity or toxicity of textile chemicals? A case study of denim jeans in the warp-dyeing phase

The extensive use and discharge of chemicals is one of the main factors leading to serious environmental pollution in the textiles and apparel industry. The chemical footprint (ChF) is a toxicity-based chemical management method that is used to quantitatively evaluate the potential toxic effects of chemical pollutants discharged during the production of textiles and apparel products on human health and environmental safety. Compared with the traditional quantity-based method, this method needs to simulate the entire process of chemicals from discharge to impact, involving a series of steps of fate, exposure and effect, which greatly increases the difficulty of modeling. A scientific question is whether it is worth spending so much effort to quantify the toxicity of chemicals. Taking the warp-dyeing phase of denim jeans as an example, this paper calculated the ChFs for both human and ecological toxicities of textile chemicals based on the USEtox model, and compared them with the values of discharge quantities. The results reveal that there is a certain inconsistency between the discharge quantity and toxicity of chemical substances. Relying solely on the amount of chemicals discharged can sometimes lead to misjudgments, emphasizing the importance of controlling the toxicity of chemicals.

Hierarchical fuzzy obstacle avoidance control of omnidirectional mobile robot for substation inspection

There are some limitations in the practical application of robot obstacle avoidance control methods. In order to realize the high-speed planning and obstacle avoidance processing of mobile robot, the path model, inspection route and path obstacles of the robot must be fully considered. Through feature extraction, the reasonable planning of substation inspection obstacle avoidance route is realized, and the control quantity set satisfying substation inspection is given. The hierarchical fuzzy obstacle avoidance control method of mobile robot is realized by using the optimal control set design. The simulation results show that the control method can solve various complex problems when the robot contour collides with obstacles, and can realize safe and fast control. The flexibility and robustness of obstacle avoidance are improved, and the motion state and speed of obstacles are also improved.

A Virtual Negative Resistor Based Common Mode Current Resonance Suppression Method for Three-Level Grid-Tied Inverter with Discontinuous PWM

The output LC filter of a photovoltaic (PV) string three-level grid-tied inverter that connects the filter capacitor neutral point to dc-link capacitor neutral point can reduce the common-mode (CM) current injected to the grid by letting the CM current circulate within the inverter. However, the internal CM current may resonate because of the existence of the resonant frequency of the internal CM LC circuit. Compared with the traditional continuous pulse-width modulation (CPWM), the resonance can be worse if discontinuous pulse-width modulation (DPWM) is applied, for the zero sequence quantity of DPWM contains more harmonics than that of CPWM. In this paper, a virtual negative resistor based common mode current resonance suppression method for a three-level grid-tied inverter is proposed to overcome the CM current resonance problem in DPWM application. Different positions of the virtual negative resistor in the equivalent CM circuit with different feedback variables are analyzed theoretically. The virtual negative resistor connected in series with the inductor in the equivalent CM circuit is selected to damp the CM current resonance for simplification and damping performance. Different from the implementation in CPWM where a pair of small voltage vectors exist and are used to adjust the CM voltage directly, the proposed method for DPWM application is implemented indirectly by adding the CM adjustment quantity to differential-mode (DM) control quantity with appropriate coefficients. Depending on the sector of DM control quantity in the α β reference frame, the coefficients are calculated using one of three specific voltage vectors. Experimental results are given to demonstrate the effectiveness of theoretical analyses and the proposed method.

Research on Dynamic Modeling and Transition Flight Strategy of VTOL UAV

A vertical take-off and landing (VTOL) unmanned aerial vehicle (UAV) can meet both VTOL and horizontal flight performance, but how to achieve a safe and stable transition is a research focus of this type of aircraft. According to the overall configuration characteristics of VTOL UAV, aerodynamic models of lift fan, lift duct and induced wing surface of VTOL UAV were established. Three flight modes of induced VTOL UAV are studied, including hover, transition and horizontal flight. The method of longitudinal flight balance of UAV in transition mode is also studied. Finally, a UAV is taken as an example to conduct the research of transition flight mode balancing and flight simulation with the method presented in this paper. The results show that the proposed method can reasonably give the control quantity and longitudinal attitude of UAV in the whole transition mode, so that the UAV can achieve a steady transition flight.

PENENTUAN STRATEGI PENINGKATAN RETRIBUSI PELAYANAN PERSAMPAHAN/KEBERSIHAN PERMUKIMAN DI KABUPATEN SITUBONDO

The regional readiness to implement regional autonomy is measured from its financial capability that mainly sourced from the Regional Own-Source Revenue (PAD). The problem is that regional retributions as one of the PAD’s components have not been able to contribute significantly to the overall regional revenue. One of the causes is the lack of potential sources exploration. This also happened to the retribution of the waste management services of the settlement in Situbondo Regency. This study aims to identify opportunities, threats, strengths, weaknesses, and strategies that can be applied to increase the waste management services of the settlement in Situbondo Regency. The strategy is formulated by using Internal External (IE) and Strengths, Weaknesses,Opportunities, and Threats (SWOT) matrixes. Findings of the research show that opportunities and threats are consisted of the potential retributions payer, increasing numbers of housing, public awareness, parliament control, retribution rates, sanctions for the retribution payer, and competitors. The strengths and weaknesses are consisted of coordination between legislative party and relevant insitutions, the quantity and quality of the retribution collector, waste services, leakage control, quantity of the waste hauler, facilities and infrastructure, socialization, SOP, retribution tariff, and retribution contribution to the PAD. The main strategy to increase the revenue from the waste management service is the expansion strategy in the form of extensification by extending the coverage area of the retribution. Keywords: Strategy, Waste Services Retribution, Settlements.

Use of Tissue-Glue–Coated Collagen Sponge (TachoSil) to Repair Minor Cerebral Dural Venous Sinus Lacerations

BACKGROUND Significant hemorrhage may occur from the cerebral venous sinuses during the dural separation from the bone flap, particularly in elderly patients. It is important to achieve an urgent hemostatic control. OBJECTIVE To evaluate the efficacy and safety of a new fixed combination tissue sealant (TachoSil) in patients with bleeding from lacerations of cerebral venous sinuses. METHODS Between September 2012 and June 2014, 57 patients (39 female, 18 male) presenting with iatrogenic tears of the superior sagittal or transverse/sigmoid sinuses were treated with a topical fibrin sealant patch. Intraoperative source of bleeding, time to bleeding control, quantity of sealant sponge used, and postoperative complications were evaluated. Time to hemostasis was used as the primary end point. RESULTS Effective hemostasis, defined as cessation of bleeding after application of topical hemostatic agent, was achieved no later than 4 minutes in all except 5 patients with persistent bleeding from the sinus. In these 5 cases, bleeding was finally stopped after application of a new larger layer of TachoSil Sponge (2 cases) or gelatin hemostatic matrix (2 cases) or fibrin glue (1 case) over the layer of TachoSil. CONCLUSION We report our experience with a new hemostasis technique to manage bleeding from iatrogenic lacerations of cerebral venous sinuses.

An Incremental Method for Cable Force Tuning of the Concrete Cable-Stayed Bridge Considering Cable-Girder Temperature Difference Effect

To ensure that the cable force tuning of Banfu No.2 bridge was carried out successfully, an incremental method for cable force tuning was presented, which took into account the cable-girder temperature difference. The cable forces were measured through frequency method. Before cable force tuning, all cable forces and temperatures of cables and girders were measured when the ambient temperature was stable, and these cable forces were taken as reference cable forces. During cable force tuning, the increment of cable force was regarded as the control quantity, while the displacement in the middle of main span was regarded as the verification quantity. After each stage, it was necessary to measure the temperatures of cables and girders and the displacement variation in the middle of the main span. To ensure the mechanical state of bridge was in control, all cable forces were measured after the 5th, 10th pairs of cables and all cables were tuned. In addition, the temperature-corrected cable forces were compared with the calculated ones, which showed the incremental method was not only accurate but also efficient.

Adaptive Robust Control of a Class of Uncertain Nonlinear Systems Based on Backstepping

Aiming at the control of a class of bounded disturbance uncertain nonlinear systems,we applied robust control and backstepping control,introduced the concept of virtual control quantity,chose Lyapunov function through stepwise recursion,offered the adaptive law of parameters estimate,designed an adaptive controller with state feedback in the premise of unknown uncertain parameters in the systems, and analyzed its stability. Compared with the conventional PID control in simulation results, the designed controller has the better robustness of the system parameter uncertainty and bounded disturbances, and can ensure the entire closed-loop system is globally asymptotically stable, thus verifying the effectiveness of the proposed control strategy.

Design and Implementation of Cholecystolithiasis Automatically Perfusion-Dissolved Instrument

In view of the difficulty to operate, low efficiency, and easy to leak of the manual perfusion method for dissolving cholecystolithiasis, an automatically perfusion-dissolved instrument is designed. By means of collecting and analysing the pressure data being outputted from pressure sensor in real time, and adjusting speed and direction of peristaltic pumps automatically to control quantity of dissolvent, so as to achieve the goal of litholysis under constant pressure in the gallbladder. The instrument has function of automatic heating and controlling temperature. Double controllers are used in the design, slave computer controls the running of each module of the instrument, and master computer is used to real-time display operation state and set parameters. Experimental results indicate that the system is stable and reliable, and with high efficiency for dissolving cholecystolithiasis, which provides a new and effective method for cholelithiasis medical treatment.