Gradient Path Research Articles

Strain‐Controlled Low‐Cycle Fatigue Behavior of a Superalloy Considering Extensive Temperature Range and Stress Concentration

ABSTRACTThis study aims to investigate the low cycle fatigue (LCF) behavior and fatigue life prediction method of an advanced solid solution–strengthened nickel‐based superalloy at various temperatures and stress concentrations. Cylindrical specimens as well as plates with three types of holes (including straight holes and inclined holes with different orientations) were designed and machined for fatigue tests. The test results revealed fatigue life decreases with the temperature increasing. Meanwhile, the fatigue lives of the plate specimens have decreased differently and are strongly dependent on the geometry and orientation of the holes. The key damage parameter related to the fatigue life was found on the strain gradient path. A criterion based on strain gradient is defined as the boundary of the damage process zone. The results show that the prediction was in good agreement with the experimental data, for the majority of the data are within a scatter band of ±2.

A Hydraulic Gradient and Stress-Controlled Erosion Apparatus for Assessing Soil Internal Erosion

Abstract Among the four dominant mechanisms of internal erosion, suffusion appears as one of the most complex. It is indeed the result of the combination of three processes: dislodgement of fine particles, transport of them, and filtration of some fluidized fine particles. These processes depend on the soil’s stress state and on the hydraulic gradient path. Thus, to ensure the repeatability of the suffusion test and to study with accuracy the influence of the aforementioned parameters, a new apparatus was developed. This apparatus is designed to test specimens under a vertical downward flow in hydraulic gradient controlled condition while controlling the confining pressure and the stress deviator, which can be either positive or negative. Ten tests on one cohesionless soil were performed in triaxial conditions, with the same mean effective stress and four different values of stress deviator. To compare with conventional suffusion results, one test is also performed in rigid wall conditions. For all performed tests, the same hydraulic gradient path was applied and particular attention is paid to the repeatability, which implies control of each test step. At the end of each test, the specimen was divided into four layers to measure post-suffusion grain size distributions. The time evolutions of the hydraulic conductivity and the erosion rate permit to identify four different phases. Each phase is characterized by two methods: one based on the hydraulic gradient and the second based on the expended energy by the fluid. The results show the great influence on the suffusion kinetics of the preferential flow paths, which localize in the body of the specimen in triaxial conditions and on the circumference in rigid wall ones. Under a constant mean effective stress, the effect of the stress deviator on the suffusion kinetics appears limited, for the tested soil and shear stress ratios.

Asymmetric jet shapes with two-dimensional jet tomography

Two-dimensional (2D) jet tomography is a promising tool to study jet medium modification in high-energy heavy-ion collisions. It combines gradient (transverse) and longitudinal jet tomography for selection of events with localized initial jet production positions. It exploits the transverse asymmetry and energy loss that depend, respectively, on the transverse gradient and jet path length inside the quark-gluon plasma (QGP). In this study, we employ 2D jet tomography to study medium modification of the jet shape of γ-triggered jets within the linear Boltzmann transport (LBT) model for jet propagation in heavy-ion collisions. Our results show that jets with small transverse asymmetry (ANn⃗) or small γ-jet asymmetry (xJγ=pTjet/pTγ) exhibit a broader jet shape than those with larger ANn⃗ or xJγ, since the former are produced at the center and go through longer path lengths while the later are off center and close to the surface of the QGP fireball. In events with finite values of ANn⃗, jet shapes are asymmetric with respect to the event plane. Hard partons at the core of the jet are deflected away from the denser region while soft partons from the medium response at large angles flow toward the denser part of QGP. Future experimental measurements of these asymmetric features of the jet shape can be used to study the transport properties of jets and medium responses. Published by the American Physical Society 2024

Janus structure design of polyimide composite foam for absorption-dominated EMI shielding and thermal insulation

In the present work, by virtue of the synergistic and independent effects of Janus structure, an asymmetric nickel-chain/multiwall carbon nanotube/polyimide (Ni/MWCNTs/PI) composite foam with absorption-dominated electromagnetic interference (EMI) shielding and thermal insulation performances was successfully fabricated through an ordered casting and directional freeze-drying strategy. Water-soluble polyamic acid (PAA) was chosen to match the oriented freeze-drying method to acquire oriented pores, and the thermal imidization process from PAA to PI exactly eliminated the interface of the multilayered structure. By controlling the electro-magnetic gradient and propagation path of the incident microwaves in the MWCNT/PI and Ni/PI layers, the PI composite foam exhibited an efficient EMI SE of 55.8 dB in the X-band with extremely low reflection characteristics (R = 0.22). The asymmetric conductive network also greatly preserved the thermal insulation properties of PI. The thermal conductivity (TC) of the Ni/MWCNT/PI composite foam was as low as 0.032 W/(m K). In addition, owing to the elimination of MWCNT/PI and Ni/PI interfaces during the thermal imidization process, the composite foam showed satisfactory compressive strength. The fabricated PI composite foam could provide reliable electromagnetic protection in complex applications and withstand high temperatures, which has great potential in cutting-edge applications such as advanced aircraft.

Exploration- and Exploitation-Driven Deep Deterministic Policy Gradient for Active SLAM in Unknown Indoor Environments

This study proposes a solution for Active Simultaneous Localization and Mapping (Active SLAM) of robots in unknown indoor environments using a combination of Deep Deterministic Policy Gradient (DDPG) path planning and the Cartographer algorithm. To enhance the convergence speed of the DDPG network and minimize collisions with obstacles, we devised a unique reward function that integrates exploration and exploitation strategies. The exploration strategy allows the robot to achieve the shortest running time and movement trajectory, enabling efficient traversal of unmapped environments. Moreover, the exploitation strategy introduces active closed loops to enhance map accuracy. We conducted experiments using the simulation platform Gazebo to validate our proposed model. The experimental results demonstrate that our model surpasses other Active SLAM methods in exploring and mapping unknown environments, achieving significant grid completeness of 98.7%.

Night construction site detection based on ghost-YOLOX

Existing target detection algorithms, when applied to night-time site monitoring, are limited by site hardware conditions, lighting conditions, fuzzy and small targets to be detected, etc., which makes it difficult to achieve good detection results. In this paper, we propose the Ghost-YOLOX algorithm for night-time site monitoring using YOLOX-X as a baseline model. In order to reduce the number of model parameters and improve the detection speed, the algorithm is based on the Ghost convolution and SimAM self-attention modules build the Sim-Ghost residual module according to the gradient path design strategy, and uses it to reconstruct the backbone and neck networks; In order to improve the detection ability of the network for fuzzy targets and small targets, based on Involution, a Cross Involution Attention (CIA) module is constructed by double cross convolution, and added to the neck network to enable the network to obtain more efficient channel and spatial attention. The experimental results show that compared with the original YOLOX-X algorithm, the Ghost-YOLOX algorithm reduces the number of parameters to 16.7% of the original model, and the detection speed increases by 2.3 times, at the same time, the average accuracy of the model has increased by 2.55%.

MPFANet: a multipath feature aggregation network for steel surface defect detection

As a crucial component of product quality surveillance in the industrial manufacturing field, surface defect detection plays a pivotal role in achieving industrial automation. Although numerous defect detection methods have been widely used in steel production, complicated defect characteristics still severely affect the accuracy and efficiency of defect detection methods. To solve this problem, we propose a multi-path feature aggregation network that can significantly improve steel defect detection performance. Firstly, we design an efficient multi-path aggregation feature extraction module combining gradient path with data path propagation design paradigm as the backbone feature extraction unit based on YOLOv5. Secondly, in the branch path of the backbone, deformable convolution is introduced to expand the effective receptive field and enhance the capability of extracting irregularly distributed defect features. Furthermore, we propose a chained feature enhanced pooling module that refines feature information to obtain feature maps containing more complicated defect details in the pooling layer. Experimental results on the publicly available steel surface defect datasets show that our proposed model achieves a mean average precision of 81.9 % on Northeastern University-DET and 72.1 % on GC10-DET improving by 4.6 % and 3.4 % over the baseline, respectively. The proposed defect detection network can achieve a balance between accuracy and efficiency, and meet the demand in practical production. The detection speed of our work reaches 41.1 frames per second (FPS) and 40.0 FPS on the above two datasets, which demonstrates that our method has achieved comprehensive performance in steel surface defect detection.

Influence of laser power on mechanical properties of FGM of SS316L and IN625 fabricated by direct metal deposition

Direct Metal Deposition (DMD) is a metal Additive Manufacturing (AM) process. It is used for producing sustainability Functionally Graded Materials (FGM) and repairing of sophisticated parts. In this present research, a commercially available DMD machine deposited three partial FGM blocks of size 26 mm wide × 34 mm thick × 32 mm heights. The commonly influence parameters on Ultimate Tensile Strength (UTS) are scan velocity and laser power. The powders used for deposition were Stainless Steel 316L (SS316L), Inconel 625 (IN625), and their three different compositions. ASTM E8 tensile samples were cut from those blocks by wire cut-EDM. Micro-tensile tests were carried out on ASTM E8 samples using a SHIMADZU micro-tensile machine. The results revealed that partial FGM sample-2 had high sustainability UTS of 532 MPa as compared to remaining two samples. It is illustrated that for joining two dissimilar materials to obtain high UTS thick layered (i.e., thickness more than 1 mm) gradient path method should be selected at the medium laser power available on the DMD machine. However, the sample-3 has higher hardness at high laser power.

Recent Progress in Hybrid Additive Manufacturing of Metallic Materials

Additive Manufacturing (AM) is an advanced technology that has been primarily driven by the demand for production efficiency, minimized energy consumption, and reduced carbon footprints. This process involves layer-by-layer material deposition based on a Computer-Aided Design (CAD) model. Compared to traditional manufacturing methods, AM has enabled the development of complex and topologically functional geometries for various service parts in record time. However, there are limitations to mass production, the building rate, the build size, and the surface quality when using metal additive manufacturing. To overcome these limitations, the combination of additive manufacturing with traditional techniques such as milling and casting holds the potential to provide novel manufacturing solutions, enabling mass production, improved geometrical features, enhanced accuracy, and damage repair through net-shape construction. This amalgamation is commonly referred to as hybrid manufacturing or multi-material additive manufacturing. This review paper aimed to explore the processes and complexities in hybrid materials, joining techniques, with a focus on maraging steels. The discussion is based on existing literature and focuses on three distinct joining methods: direct joining, gradient path joining, and intermediate section joining. Additionally, current challenges for the development of the ideal heat treatment for hybrid metals are discussed, and future prospects of hybrid additive manufacturing are also covered.

Research and application of nodal stress correction at stiffness mutation position for fatigue life evaluation

This paper proposes a two-level stress correction method to overcome the limitations of the element stress average method that is typically used to calculate the nodal stress in finite element analyses and increase the fatigue life evaluation accuracy at the stiffness mutation positions of large-scale structure. In the first stage, a standard-deviation-weighted stress smoothing method is used to address the high element stress dispersion at the stiffness mutation point. The second stage involves a stress gradient correction method established based on the theory that the nodal stress is affected by other nodal stresses on the stress gradient path. The nodal stresses of the key points of an 80-ton gondola car body are extracted using the two-level stress correction method, and the fatigue life of the key points is evaluated considering the load spectrum of the Daqin coal line. The fatigue lives corresponding to the measured stress spectrum at the key points are compared with the simulated values. Compared with that obtained by the traditional method, the fatigue life of the key joints obtained by the proposed method is closer to the actual fatigue life. Additionally, the nodal stress at the stiffness mutation position obtained by the proposed method is more accurate. Therefore, the two-level stress correction method is a promising platform for the fatigue life evaluation of large-scale structures.

SLP-Improved DDPG Path-Planning Algorithm for Mobile Robot in Large-Scale Dynamic Environment

Navigating robots through large-scale environments while avoiding dynamic obstacles is a crucial challenge in robotics. This study proposes an improved deep deterministic policy gradient (DDPG) path planning algorithm incorporating sequential linear path planning (SLP) to address this challenge. This research aims to enhance the stability and efficiency of traditional DDPG algorithms by utilizing the strengths of SLP and achieving a better balance between stability and real-time performance. Our algorithm generates a series of sub-goals using SLP, based on a quick calculation of the robot's driving path, and then uses DDPG to follow these sub-goals for path planning. The experimental results demonstrate that the proposed SLP-enhanced DDPG path planning algorithm outperforms traditional DDPG algorithms by effectively navigating the robot through large-scale dynamic environments while avoiding obstacles. Specifically, the proposed algorithm improves the success rate by 12.33% compared to the traditional DDPG algorithm and 29.67% compared to the A*+DDPG algorithm in navigating the robot to the goal while avoiding obstacles.

Effects of temperature gradient and beam path height from heat source on phase structure and mutual coherence functions of a light beam propagating through convective air turbulence

In this paper, we investigate the effects of different values of temperature gradient (TG) and the distance of a plane wave path from a flat heat source generating an anisotropic and non-Kolmogorov convective air turbulence medium on the phase structure function (PSF) and mutual coherence function (MCF) of the light beam propagating through the medium. The non-Kolmogorov and anisotropic convective air turbulence is created using an electrical heater with a surface size of 50 cm × 100 cm. The heater temperature is changeable from room temperature to 100 °C. The laser beam with a diameter of 20 cm passes through the turbulent medium at different distances from the heater surface. At the end of the path, the wavefront of the light beam is reconstructed using a two-channel moiré wavefront sensor. Then, the PSF and MCF are calculated, and the effects of different TGs and the different beam path heights from the heater are studied. Results show that with increasing the TG and decreasing the beam path distance from the heat source, the turbulence intensity and PSF increase, while the MCF decreases.

Fabrication and characterization of stainless steel 308 L / Inconel 625 functionally graded material with continuous change in composition by dual-wire arc additive manufacturing

Additive manufacturing (AM) technology can fabricate functionally graded materials (FGMs) with a layered gradient change in chemical composition and microstructure by changing the composition ratio of different filler materials layer by layer, which indeed have uneven and uncontrolled composition gradients between layers. In the present work, FGMs of stainless steel 308 L and Inconel 625, with continuous change in composition, were fabricated by dual-wire arc additive manufacturing (D-WAAM) by changing the speeds of dual wires in each single layer. The chemical composition, microstructure, phases, and mechanical properties of the FGM were investigated. The results showed that the composition gradient was smoothly distributed along the torch-travelling direction in each single layer, and the composition at the same position along the building direction was stable. With the increase in the content of Inconel 625, the austenite dendrites, which was the main microstructure, became finer first and then coarser, but there was no apparent abrupt change in microstructure in the gradient zone, which made the mechanical properties also show a smooth change. The mechanical properties were weak when the content of Inconel 625 was within 10–50 wt% due to the secondary phases (MC, Laves) distributed at the grain boundary. The proposed fabrication approach of FGM also showed advantages and flexibility in the design of gradient path, or the design of structure size if there is a requirement on the size in the building direction.

Hot cracking during the fabrication of Inconel 625/stainless steel 308 L functionally graded material by dual-wire arc additive manufacturing

In the present work, dual-wire arc additive manufacturing was used to fabricate the functionally graded material (FGM) with a smooth composition transition from 100 wt% Inconel 625 (IN625) to 100 wt% stainless steel 308 L, whose composition transition was along the torch-travelling direction. With such a composition transition, position with the weakest mechanical properties could be clearly and easily located in the composition gradient path, allowing the issue to be fully exposed. During the fabrication, cracks were found near the position with IN625 of 20 wt%. By analyzing the fracture morphology and crack location, they were judged as liquation cracks, which belong to hot cracks. The segregation and aggregation of carbides at the grain boundary formed the low-melting-temperature eutectic phase, which is liquefied into the liquid film by the heating of subsequent layers and is then pulled apart by residual stress. According to the experimental results and the calculations of phase diagrams, the cracks always appeared near the position with IN625 of 20 wt%, where the FGM has the highest crack sensitivity. Therefore, it was determined as the weakest position of the FGM and its weakening mechanism could be clarified easier owing to the composition transition, which provides a high possibility to get better mechanical properties if a more targeted optimization method is applied. Process parameter optimization reduces the heat input per unit height to thin dendrites and to alleviate cracking, but there is still a cracking tendency in the weak composition range. The composition gradient path optimization, by removal of the corresponding composition range, can solve the cracking issue more thoroughly, and the tensile strength and elongation increased by 39.5 % and 221.7 %, respectively, which greatly improved the mechanical properties of the FGM.

A Simulation Optimization Approach for the Appointment Scheduling Problem with Decision-Dependent Uncertainties

The appointment scheduling problem (ASP) studies how to manage patient arrivals to a healthcare system to improve system performance. An important challenge occurs when some patients may not show up for an appointment. Although the ASP is well studied in the literature, the vast majority of the existing work does not consider the well-observed phenomenon that patient no-show is influenced by the appointment time, the usual decision variable in the ASP. This paper studies the ASP with random service time (exogenous uncertainty) with known distribution and patient decision-dependent no-show behavior (endogenous uncertainty). This problem belongs to the class of stochastic optimization with decision-dependent uncertainties. Such problems are notoriously difficult as they are typically nonconvex. We propose a stochastic projected gradient path (SPGP) method to solve the problem, which requires the development of a gradient estimator of the objective function—a nontrivial task, as the literature on gradient-based optimization algorithms for problems with decision-dependent uncertainty is very scarce and unsuitable for our model. Our method can solve the ASP problem under arbitrarily smooth show-up probability functions. We present solutions under different patterns of no-show behavior and demonstrate that breaking the assumption of constant show-up probability substantially changes the scheduling solutions. We conduct numerical experiments in a variety of settings to compare our results with those obtained with a distributionally robust optimization method developed in the literature. The cost reduction obtained with our method, which we call the value of distribution information, can be interpreted as how much the system performance can be improved by knowing the distribution of the service times, compared to not knowing it. We observe that the value of distribution information is up to 31% of the baseline cost, and that such value is higher when the system is crowded or/and the waiting time cost is relatively high. Summary of Contribution: This paper studies an appointment scheduling problem under time-dependent patient no-show behavior, a situation commonly observed in practice. The problem belongs to the class of stochastic optimization problems with decision-dependent uncertainties in the operations research literature. Such problems are notoriously difficult to solve as a result of the lack of convexity, and the present case requires different techniques because of the presence of continuous distributions for the service times. A stochastic projected gradient path method, which includes the development of specialized techniques to estimate the gradient of the objective function, is proposed to solve the problem. For problems with a similar structure, the algorithm can be applied once the gradient estimator of the objective function is obtained. Extensive numerical studies are presented to demonstrate the quality of the solutions, the importance of modeling time-dependent no-shows in appointment scheduling, and the value of using distribution information about the service times.

Design of an additively manufactured functionally graded material of 316 stainless steel and Ti-6Al-4V with Ni-20Cr, Cr, and V intermediate compositions

This study presents a method for designing a computationally informed gradient pathway to fabricate a functionally graded material (FGM) with terminal alloys of 316 stainless steel (SS316) and Ti-6Al-4V via directed energy deposition additive manufacturing with powder feedstock. The grading is accomplished through the introduction of intermediate elements and alloys (Ni-20Cr, Cr, and V) to avoid the brittle Fe-Ti intermetallic phases that form in the direct liquid phase joining of Ti-alloys and stainless steels. Using a combination of equilibrium calculations and Scheil-Gulliver simulations, a compositional pathway was designed to avoid deleterious phases. FGM samples were fabricated and experimentally characterized to determine the viability of the pathway. A change in phases from fcc to bcc was predicted to occur within the Ni-20Cr/Cr gradient region, and this was validated through experimental characterization. No detrimental phases (intermetallic, Laves, or σ phases) formed along the gradient path, demonstrating a successful computationally-informed design and fabrication of an FGM from SS316 to Ti-6Al-4V.

Pengaruh Gradien 40o/oo Terhadap Jumlah LRV Yang Ditarik Kereta Penolong untuk Menghindari Terjadinya Slip Pada LRT Jakarta

LRT Jakarta is one of the train operators in Indonesia. Apart from the passenger train (LRV), the Jakarta LRT also has a helper train (MRV). At the Jakarta LRT, the MRV operation has to pass a very steep incline, namely a 40o/oo gradient. This can result in a high probability of slippage. Such an incident can be avoided if we know how much the adhesion pull of the tow cart and the total resistance of the tow cart. For that we need further calculations regarding the total resistance of the train to the adhesion tensile force. So that in this final project will produce the maximum number of trains that can be pulled by the locomotive so that no slip occurs. With quantitative methods, data collection and calculation / analysis, the expected results are obtained in this final report. So that it can be seen that the maximum MRV traction effort is 107 kN and the resistance by pulling 3 LRV is 99 kN. Slip occurs when the resistance exceeds maximum traction effort. So it can be concluded that the MRV can attract 3 LRV without any slip when on the 40o/oo gradient path.

General discriminative optimization for point set registration

Point set registration has been actively studied in computer vision and graphics. Optimization algorithms are at the core of solving registration problems. Traditional optimization approaches are mainly based on the gradient of objective functions. The derivation of objective functions makes it challenging to find optimal solutions for complex optimization models, especially for those applications where accuracy is critical. Learning-based optimization is a novel approach to address this problem, which learns the gradient direction from datasets. However, many learning-based optimization algorithms learn gradient directions via a single feature extracted from the dataset, which will cause the updating direction to be vulnerable to perturbations around the data, thus falling into a bad stationary point. This paper proposes the General Discriminative Optimization (GDO) method that updates a gradient path automatically through the trade-off among contributions of different features on updating gradients. We illustrate the benefits of GDO with tasks of 3D point set registrations and show that GDO outperforms the state-of-the-art registration methods in terms of accuracy and robustness to perturbations.

Serialized gradient chromatography for the digital blending of colored fibers and spinning of gradient colored yarn

Gradient colored yarns are manufactured by controlling the blending ratios of three-primary-colored fibers in a slight distribution of gradients along the yarn length, thereby resulting in a continuous natural variation in mixed colors of the fibers throughout the whole yarn. The spinning of gradient colored yarns still remains a challenge, which requires the reliance on digital blending theory of colored fibers and the supporting of multi-channel computer numerical control (CNC) spinning technique. This paper constructed a three-primary-colored fiber gridded color mixing model and its mass mixing matrix and color mixing chromatography matrix by mass discretization and coupling pairing with a 10% gradient for the three-primary-colored fibers. With the aim of continuous natural gradient of mixed colors, the blending ratio gradient path of three-primary-colored fibers was planned based on the mass mixing matrix, and a method of regulating the gradient of color difference between adjacent color segments was proposed. In order to realize the natural gradient of color of the forming yarn, the spinning mechanism of gradient colored yarn was established based on three-channel CNC spinning mechanism and the time-series yarn simulation model, and the time-series spinning processing parameters of three-channel CNC spinning machine were devised. Four gradient colored yarns with different gradient paths were designed and prepared, the linear density, twist, unevenness, surface hairiness, and tensile strength of the spun yarns were measured, compared, and analyzed, and knitted fabrics with color gradient effect were fabricated by small circular knitting machine to obtain continuous and natural color transition with a dreamy and mysterious color effect.

A new quality management system of admittance indicators to improve industrial land use efficiency in the Beijing−Tianjin−Hebei region

Given China’s rapid urbanization, the continual adjustment of industrial land admittance indicators (ILAIs) to promote the optimal allocation and utilization of industrial land is critical for urban land use optimization and sustainable urban development. Unlike previous studies that have focused on qualitative analysis and traditional economic and statistical methods to modify ILAIs via sample survey data, this paper proposes a new theoretical framework for determining the optimal regulation of ILAIs to improve land use efficiency from a quality management perspective, analyses the differences in ILAIs in industrial space and types at multiple scales and sets and modifies the diverse function values of ILAIs by sub-region and sub-industrial sector via a probability model based on big data for 2007–2016 for the Beijing−Tianjin−Hebei (BTH) region. The findings were as follows: (1) The floor area ratio (FAR), greening ratio (GR), building density (BD) and fixed asset investment intensity (FAII) of industrial land in BTH were found to be low within national standards and exhibited great excavation potential. (2) The ILAIs exhibited spatial heterogeneity, with a significant multicore circular structure of peaks and fluctuations and with FAR, BD and FAII values higher in the Jing-Jin region and in the southern and northeastern regions of Hebei Province but lower in northwestern BTH, while the GR’s spatial pattern showed the opposite trend. (3) Both the five classified sub-regions and industry sub-types displayed marked variations in ILAIs, indicating that it was necessary to modify ILAIs by sub-region and sub-industrial sector. (4) Industrial land use efficiency in BTH was further revealed at the general, non-intensive and extensive levels and was found to vary considerable by sub-type. The land use mode of the service industry was the most efficient and intensive, followed by that of the high-tech industry. The land intensiveness of various light industry sectors was clearly distinct, while the chemical, metallurgy and equipment manufacturing industries were of moderate to non-intensive levels. The lowest values were found for the mining and coking industry. (5) The probability model is suggested to be an effective method for modifying the multifunctional values of ILAIs. Relative to national standards, the improved control values of ILAIs were higher at the regional level, and for different sub-regions not fully proportional to their development levels, they were higher or lower than their regional counterparts, even deviating from national standards. The revised FAR of each industry was also found to be higher and directly proportional to existing national standards; however, their improvement exhibited the opposite trend. ILAIs performance was bifurcated in terms of industry sub-types and economic-geographic regions. This study suggests establishing twofold ILAIs of “land use efficiency and industrial development”, developing gradient path guidance for ILAIs threshold values and enhancing ILAIs implementation flexibility to realize the precise matching of industry transfer and acceptance and the coordinated and balanced development of the entire region and constructing a sound “access-adjustment-exit” circulation system for applying ILAIs throughout the life cycle of industrial land.