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Among the factors affecting concrete durability, permeability responds to the density of concrete and the ability of concrete resisting external medium penetration into the concrete.
Researches showed that multi-step mixing can improve the internal pore structure of concrete and the working performance and mechanical property and durability of concrete without any increase in raw material and without extended mixing time.

To solve this problem, system-level equality constraints are modified with a relax factor [5], the penalty-function method [6].
(1) Design Variables Main independent design parameters affecting the spring’s working performance are the spring wire diameter d, mean diameter of coil D, number of effective coils n .Therefore, in the spring optimization model, the variables are (2) (2) Objective function Optimal design object of spring should be maximizing the economic benefit.
In order to guarantee the spring’s normal work, spring working stress should be less than or equal to the allowable shear stress, namely (6) Where F is the applied load; k is the curvature correction factor .
(3) In a word, the whole mechanical characters of the MOCO final design case are better than the initial design and the other three design case. 5 Conclusions A multi-objective collaborative optimization model was used to optimize a spring structure.
Multi-objective Optimum Design of Structural and Property Parameters for Spring[J].

Physical parameters of the main mechanical rock were shown in table 1.
The side resistance was affected by many factors, including the strength of pile, its diameter, rock characteristics around the pile, initial stress of the rock.
Tip resistance affected not only with the strength of the bearing layer, but also with depth buried in rock, tip diameter, tip displacement and the intensity of rock.
The results show that the bearing property of segment in mud rock area is similar to the friction piles.

Similarly, there are some factors that can not be theoretically modeled in the EDM process of PCD.
are the factors.
The three factors and four levels of each factors are shown in Table 1.
Fig. 3 shows the graphs of MRR and Ra that use the control variable method to change one of the factors and keep the other two factors respectively.
In order to reflect the relationship between factors more fully, these three factors are further studied by experiments.

Design and Analysis of Model Following Control Structure with Nonlinear Plant JERZY Brzozka Department of Control Systems and Robotics, Maritime University of Szczecin, Mechanical Faculty, 70-205 Szczecin, Podgorna 51/53 St., Polan e-mail: j.brzozka@am.szczecin.pl Keywords: input-state, input-output linearization, model following control, ship course control Abstract.
The system in Fig. 2 has better properties than a system with an auxiliary proportional controller with an input signal (Fig. 1).
(The even factors in (Eq. 8) can be neglected [8]).
Assuming that the signal error is (Eq. 15) (15) where ψR – denotes desired ship course angle, and that the transient component of the course control error describes the following differential equation (Eq. 16) (16) and then placing (Eq. 15) into (Eq. 16) and assuming that, we obtain the equation (Eq. 17) (17) Substituting, in turn (Eq. 17) into (Eq. 14), and taking into account that, we obtain nonlinear control law (Eq. 18) [9] (18) b1 coefficient affects the rate of decay of the oscillations of the control system (a high value of b1 causes intense oscillation suppression); b0 coefficient affects the frequency of oscillation (the increasing b0 increases the frequency of oscillation).
The nonlinear plant, linearized by the input-output method has better properties (the shorter time control, acceptable control signals).

Triyana1, 2 1Nanomaterials Research Group, Integrated Research and Testing Laboratory (LPPT), Gadjah Mada University,Yogyakarta 55281, Indonesia. 2Department of Physics, Faculty of Mathematics and Natural of Sciences, Gadjah Mada University,Yogyakarta 55281, Indonesia. 3Department of Mechanical Engineering, Faculty of Engineering, GadjahMada University, Yogyakarta 55281, Indonesia aEmail: hsosiati@ugm.ac.id, hsosiati@gmail.com (corresponding author) Keywords: Sisal fiber, cellulose nanocrystal, SEM, TEM, XRD, FTIR ABSTRACT.
The origin of the cellulose and the isolation method are the key factors affecting the morphology of isolated CNCs.
Dufresne, Cellulose nanocrystals and related nanocomposites: Review of some properties and challenges, J.
Panaitescu, Morphology and thermal properties of PLA-cellulose nanofibers composites, Carbohydrate Polym. 91 (2013) 377-384

Comparison of penetration depth and strength parameters To determine the changes of the material properties, in particular their strength, due to the utilization of the new infiltration process, various material tests were performed.
Figure 4: Comparison of material properties using manual or automatic infiltration Comparison of process duration and cost The automatic infiltration results in a significant increase of the process duration for the overall manufacturing process.
The main purpose of this reworking is to improve the tribological properties of the tool during the forming process.
Small cracks on the surface of the female die did not affect the application of the “hybrid tool”.
Oh, A benchmark study on rapid prototyping processes and machines: Quantitative comparisons of mechanical properties, accuracy, roughness, speed, and material cost, in: Proceedings of the Institution of Mechanical Engineers, Part B (Journal of Engineering Manufacture), Birmingham, AL (USA): Professional Engineering Publishing (2008) 201-215

Surface Electrical Property.
Fly ash particles with good dispersing properties and high mechanical strength distributed evenly in the sludge floc structure, providing a loose porous skeleton of support for sludge and improving compression resistance of sludge.
Ceramsite obtained from water and wastewater sludge and its characteristics affected by (Fe2O3+CaO+MgO)/(SiO2+Al2O3), J.
Ceramsite obtained from water and wastewater sludge and its characteristics affected by Fe2O3, CaO, and MgO, J.
Thickening properties and utilization of sewage sludge modified by shale[J].

It also produces better surface integrity and compress residual stress, which improves the properties of work metals such as fatigue.
To illustrate the effect of high-pressure jet assisted machining on the properties of the work piece of Ti-6-Al-4V and the depth profile of its residual stress, X -ray defractometer was used.
A combination of mechanical and thermal affect the residual stresses induced by machining operatins.
In service, this damage can lead to a great degradation of properties such as fatigue strength and stress corrosion resistance.
Thus, optimum properties usually are achieved during machining of titanium.

The leaves hold a gooey semitransparent bitter gel that has antiviral and antibacterial properties, in addition, healing properties.
Finally, investigate of final samples performance for the different barrier properties.
The test results of the odor absorption test were analyzed by using a single factor of variance (ANOVA) test.
Bursting strength resistance of produced samples Evaluation of Produced Samples Properties Figures 16 & 17 and Table 4 show the radar evaluation charts by calculating the area of the properties for each group of samples.
Also, it was found that the increase of the non-woven sub-layers' number of the produced samples was affected on the properties of the final sample clearly, especially on contact angle for both surfaces, bursting strength resistance, and stiffness values properties.