Nordin Zakaria- PhD, Universiti Sains Malaysia
- Lecturer at Malaysia
Nordin Zakaria
- PhD, Universiti Sains Malaysia
- Lecturer at Malaysia
About
106
Publications
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840
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Introduction
While my research over the years span numerous fields, I am currently focusing on my 'true' scientific passion: the study of mind and society by computational means.
Current institution
Malaysia
Current position
- Lecturer
Publications
Publications (106)
We discuss in this paper an agent-based social simulation model that describes the propagation of political belief in Malaysia. Worldview map is used as the representational scheme for political belief. Inter-agent interaction propagates the belief throughout the agent population, subject to similarity of emotion between the interacting agents and...
The high-dimensional search space involved in markerless full-body articulated human motion tracking from multiple-views video sequences has led to a number of solutions based on metaheuristics, the most recent form of which is Particle Swarm Optimization (PSO). However, the classical PSO suffers from premature convergence and it is trapped easily...
I speculate upon the idea that qualia comprise of quanta or packets, and that each packet is generated by physical processes within a neuron, possibly at the quantum level. Pattern-specific neuronal activation causes wave-like interactions among the packets, leading to phenomenal sensation. In essence, I provide in this paper a new panpsychic inter...
Agent-based social simulations are typically described in imperative form. While this facilitates implementation as computer programs, it makes implicit the different assumptions made, both about the functional form and the causal ordering involved. As a solution to the problem, a probabilistic graphical model, Action Network (AN), is proposed in t...
A probabilistic graphical model, Neuronal Unit of Thoughts (NUTs), is proposed in this paper that offers a formalism for the integration of lower-level cognitions. Nodes or neurons in NUTs represent sensory data or mental concepts or actions, and edges the causal relation between them. A node affects a change in the Action Potential(AP) of its chil...
Accurate detection and classification of teeth is the first step in dental disease diagnosis. However, the same class of tooth exhibits significant variations in surface appearance. Moreover, the complex geometrical structure poses challenges in learning discriminative features among the different tooth classes. Due to these complex features, tooth...
Within the ever-growing healthcare industry, dental informatics is a burgeoning field of
study. One of the major obstacles to the health care system’s transformation is obtaining knowledge
and insightful data from complex, high-dimensional, and diverse sources. Modern biomedical
research, for instance, has seen an increase in the use of complex, he...
Genetic Algorithm (GA) and Approximation Algorithms (AA)
are two popular approximate solutions for NP-complete problems such as the Set Covering Problem (SCP). AA provides solution guarantee. GA, on the other hand, can potentially find better solutions. Of its many stages, the initial population (IP) is an interesting one. Despite its proven signif...
In this paper, a new model of 3-qubits quantum annealing processor is designed. The spin-chain model is used to simulate the quantum annealing processor. The Hamiltonian which describes the system is introduced and analytically solved using the unitary operator method taking into account, processor in, ground state. The generated entanglement betwe...
In this study, we developed a computing architecture and algorithms for supporting soft realtime task scheduling in a cloud computing environment through the dynamic provisioning of virtual machines. The architecture integrated three modified soft real-time task scheduling algorithms, namely, Earliest Deadline First (EDF), Earliest Deadline until Z...
This paper presents a practical performance analysing of two real-time multiprocessor
scheduling algorithms, namely, Largest Remaining Execution-Time and Local Time Domain
(LRE-TL) and Unfair Semi-Greedy (USG). The analysis is intended to reflect the behindthe-scene
time overhead incurred by optimal real-time algorithms such as LRE-TL. The
overhead...
Batch Self-Organizing Map (Batch-SOM) is being successfully used for clustering and visualization of high-dimensional datasets in a wide variety of domains. Although the structure of its training algorithm has a high potential for parallelization, focus of the previous efforts has been on the original Step-wise SOM. This gap is due to the facts tha...
While Genetic Algorithm (GA) is a powerful tool for combinatorial optimization, the vast population of candidate solutions it typically deploys and algorithm’s intrinsic randomness lead to difficulty in understanding its search behavior. We discuss in this paper a clustering-based visualization tool for GA that attempts to mediate this problem. GA...
Data compression and encryption are key components of commonly deployed platforms such as Hadoop. Numerous data compression and encryption tools are presently available on such platforms and the tools are characteristically applied in sequence, i.e., compression followed by encryption or encryption followed by compression. This paper focuses on the...
Metocean time-series data is generally classified as highly chaotic thus making the analysis process tedious. The main aim of forecasting Metocean data is to obtain an effective solution for offshore engineering projects, such analysis of environmental conditions is vital to the choices made during planning and operational stage which must be effic...
This paper presents a stochastic partially optimized cyclic shift crossover operator for the optimization of the multi-objective vehicle routing problem with time windows using genetic algorithms. The aim of the paper is to show how the combination of simple stochastic rules and sequential appendage policies addresses a common limitation of the tra...
Recently, the increasing demand for computing has led to the development of computational grids. Subsequently, the increased demand has also resulted in the significant heat management problem in the computational grid environment. The increased in computational workloads caused the servers to produce more heat, which consequently upsurges the cool...
This paper focuses the problem of combining compression with encryption for large data. Towards this end, a data encoding scheme for combined data compression and encryption, codenamed CSDC, is introduced. The scheme supports 128-bit key lengths. The data compression is achieved through Huffman coding and encryption through chaotic key-based expans...
Gas compressor performance is vital in oil and gas industry because of the equipment criticality which requires continuous operations. Plant operators often face difficulties in predicting appropriate time for maintenance and would usually rely on time based predictive maintenance intervals as recommended by original equipment manufacturer (OEM). T...
Electricity consumption typically forms the biggest portion of a Data Centre's operational cost, with the biggest consumers, in roughly equal proportion, being the servers and the cooling units. In an effort to reduce electricity consumption, in this paper, we propose a grid scheduling algorithm that takes advantage of a prior Gas-District Cooling...
A partially entangled network is generated between four nodes by using two pairs of Werner state. The non-connect nodes are connected via the Dzyaloshiniskii-Moriya (DM) interaction. The effect of DM' strength and its directions on the degree of entanglement is discussed. It is shown the upper bounds of entanglement, which is generated between two...
In this paper, we present an efficient global real- time multiprocessor scheduling algorithm based on the beneficial Zero-Laxity policy. The algorithm selects tasks for execution based on their execution requirements. Tasks with largest execution requirements are always scheduled first; however when a task reaches zero laxity it is given the highes...
Electricity consumption for cooling purpose is known to be the most expensive operational cost factor in data centers. Inefficient cooling leads to high temperature and this in turn leads to hardware failure. This paper proposes a Thermal Aware Modified Least Slack Time Round Robin Based (MLST-RR) scheduling algorithm that can avoid high thermal st...
I speculate upon the idea that qualia comprise of quanta or packets, and that each packet is generated by physical processes within a neuron, possibly at the quantum level. Pattern-specific neuronal activation causes wave-like interactions among the packets, leading to phenomenal sensation. In essence, I provide in this paper a new panpsychic inter...
I speculate upon the idea that qualia comprise of quanta or packets, and that each packet is generated by physical processes within a neuron, possibly at the quantum level. Pattern-specific neuronal activation causes wave-like interactions among the packets, leading to phenomenal sensation. In essence, I provide in this paper a new panpsychic inter...
Over the decades people have seen a change from large mainframe computing to commodity, off-the-shelf clusters of high performance computers. Currently data centers have thousands or tens of thousands of high performance computers that provides services as well as computation for tens or hundreds of thousands of users. Traditional IT challenges suc...
In this paper, we address the problem of three dimensional human pose tracking and estimation using Particle Swarm Optimization (PSO) with an improved silhouette extraction mechanism. In this work, the tracking problem is formulated as a nonlinear function optimization problem so the main objective is to optimize the fitness function between the 3D...
I introduce in this paper the notion of social simulation as a news analysis tool. Given an event of interest, a person with only secondary, incomplete information on the event constructs a social simulation in an attempt to better interpret or understand it. Published and unpublished facts, opinions, and observations from media sources both on-lin...
Gas District Cooling (GDC) provides electricity and chilled water to facilities with relatively low running cost and has the potential to reduce CO2 emission as it can make effective use of wasted energy. However, the present CO2 emission tends to be higher than expected due to the chilled water supply-demand gap. To efficiently manage the gap, thi...
The complexity of the Vehicle Routing Problems (VRPs) and their applications in our day to day life has arnered a lot of attentions in the area of optimization. Recently, attentions have turned to multi-objective VRPs with Multi-Objective Genetic Algorithms (MOGAs). MOGAs, thanks to its genetic operators such as selection, crossover, and/or mutatio...
A modified version of Local Remaining Execution-TL (LRE-TL) real-time multiprocessor scheduling algorithm is presented. LRE-TL uses two events to make scheduling decisions: The Bottom (B) event and the Critical (C) event. Event B occurs when a task consumes its local utilization meaning that it has to be preempted. Event C occurs when a task's loca...
Automatic human motion tracking in video sequences is one of the most frequently tackled tasks in computer vision community. The goal of human motion capture is to estimate the joints angles of human body at any time. However, this is one of the most challenging problem in computer vision and pattern recognition due to the high-dimensional search s...
Datacenters are a fundamental part of the social infrastructure in today's world. While outdoor free air is used to cool datacenter computers, the technique is difficult to apply in hot countries. This article outlines the concept behind an energy-efficient datacenter called the GDC-DC that is the product of joint research by Hitachi and Universiti...
We study a model of a multi-photon interaction of a single Cooper pair box with a cavity field. The exchange of the information using this system is studied. We quantify the fidelity of the transmitted information. The effect of the system parameters (detuning parameter, field photons, state density and mean photon number) in the fidelity of the tr...
We investigate the entropy squeezing and entanglement of the Cooper-pair box interacting with multi-photon cavity field. The field is prepared initially in the coherent state, while the Cooper-pair box is assumed to start from a mixed state. We find that the number of photons and the detuning parameters play an important role in the entropy squeezi...
The visualization of search space makes it easy to understand the behavior of the Genetic Algorithm (GA). The authors propose a novel way for representation of multidimensional search space of the GA using 2-D graph. This is carried out based on the gene values of the current generation, and human intervention is only required after several generat...
In this article we designed a quantum network consists of four nodes using pairs of partial entangled state
(Werner-state). The nodes of this network are connected via Dzyaloshiniskii-Moriya (DM) interaction. The entanglement is quantified between all different nodes using Wootters concurrence. It is shown that there is a maximum entangled state g...
In this paper, the effect of homogeneous and non-homogeneous magnetic fields as an external noisy on the entanglement dynamics over partial entangled state quantum network is studied. The Dzyaloshiniskii-Moriya (DM) interaction is used to generate entangled network from partially entangled states in the presence of the spin-orbit coupling. The enta...
Soft real-time systems are systems that can tolerate deadline misses but at the expense of degradation in quality of service. Many of the Scheduling algorithms used to schedule real-time tasks in a multiprocessor soft real-time systems are extended from their uniprocessor counterparts such as Global Earliest Deadline First (G-EDF) and Least Laxity...
We discuss the interaction of a single Cooper pair box interacting with a multi-photon field. The dynamical behavior is investigated using the quantum mutual entropy. The results show that the system parameters (the number of quanta and detuning parameters) play an important role in entanglement. This result might shed the light on the possibility...
Nowadays, there are different types of computing infrastructures, like grids and volunteer communities, which have distinct needs and the preservation of energy or other resources is chief among them. This paper presents an attempt to incorporate pluggable scheduling into an existing open-source volunteer computing system named BOINC. Our efforts p...
Pen pressure is an input channel typically available in tablet pen device. To
date, little attention has been paid to the use of pressure in the domain of
graphical interaction, its usage largely limited to drawing and painting
program, typically for varying brush characteristic such as stroke width,
opacity and color. In this paper, we explore the...
Dzyaloshiniskii-Moriya (DM) interaction in three directions (Dx, Dy and Dz) is used to generate entangled network from partially entangled states in the presence of the spin-orbit coupling. The effect of the spin coupling on the entanglement between any two nodes of the network is investigated. The entanglement is quantified using Woottores concurr...
Most currently existing optimal real-time multiprocessor scheduling algorithms follow the fairness rule, in which all tasks are forced to make progress in their executions proportional to their utilization, to ensure the optimality of the algorithm. However, obeying the fairness rule results in large number of task preemptions and migrations and th...
R&D 2014 Featured Articles Datacenters are a fundamental part of the social infrastructure in todays world. While outdoor free air is used to cool datacenter computers, the technique is diffi cult to apply in hot countries. This article outlines the concept behind an energy-effi cient datacenter called the GDC-DC that is the product of joint resear...
In this paper we present a modification of Local Remaining Execution (LRE-TL) real-time multiprocessor scheduling algorithm to reduce tasks migration significantly. LRE-TL, which is based on the concept of fluid scheduling, makes scheduling decisions using two events. The Bottom (B) event occurs when a task consumes its local utilization thus; it h...
Dzyaloshiniskii–Moriya (DM) interaction is used to generate entangled network from partially entangled states in the presence of the spin–orbit coupling. The effect of the spin coupling on the entanglement between any two nodes of the network is investigated. It is shown that the entanglement decays as the coupling increases. For larger values of t...
We study the dynamical properties of a cavity field coupling to a Cooper pair box (CPB). We assumed that the CPB is prepared initially in a mixed state with a coherent state for the field. By solving the time-dependent equations using the evolution operator, it shows that mean numbers of Cooper pairs is affected by the detuning. The mean number of...
We study the interaction of the single-Cooper pairbox interacting with a cavity field. The solution of the system dynamics is obtained. The entropy as a measure of the entanglement between the qubit and the field is calculated and compared with the field purity. It is shown that the general behavior of the entropy as well as the field purity is aff...
Gas District Cooling (GDC) provides electricity and chilled water to facilities with relatively low running cost and has the potential to reduce CO2 emission as it can make effective use of wasted energy. However, the present CO2 emission tends to be higher than expected due to the chilled water supply-demand gap. To efficiently manage the gap, thi...
In this paper, we explore the use of hybrid genetic algorithm for optimized clustering and distribution of Finite Difference Time Domain (FDTD) computation over a large number of desktop computers and servers. Given a large number of computers, we first attempt to compute an optimal set of clusters. The clustering takes into consideration similarit...
The problems which are NP-complete in nature are always attracting the computer scientists to develop some heuristic algorithms, generating optimal solution in time-space efficient manner compared to the existing ones. Coloring of the vertices of a graph with minimum number of colours belongs to the same category, where the algorithm designers are...
A grid is an infrastructure for resource sharing. At present, many scientific applications require high computing power in processing, which can only be achieved by using the computational grid. For the selection and allocation of grid resources to current and future applications, grid job scheduling is playing a very vital role for computational g...
Grid computing enables sharing, selection and aggregation of computing resources for solving complex and large-scale scientific problems. Grid scheduling is playing a vital role for the efficient and effective execution of jobs on computational grids. Most of the scheduling algorithms do not consider user and system objectives at the same time. The...
Grid computing is the enabling technology for high performance computing in scientific and large scale computing applications. A number of powerful parallel systems have been built with increasing number of processors and multi-core solutions in order to meet the increased computational demands. Scheduling is a fundamental issue in achieving high p...
In this study, we examined the effect of perfectionism on learning programming using different computer applications, and the levels of motivational and attainment. Three representative multimedia-oriented programming tools are used: Visual Basic Express, Scratch and a 2D-Programmable PyGame Based Computer Game. A total of 591 of secondary school s...
The demand for Unmanned Aerial Vehicle (UAV) extends to various civil and military missions. While the use of remotely controlled UAV reduces the rate of human casualties in hazardous environments, it is reported that most of UAV accidents are caused by human factor errors. Automated path planning is required and because of the multi-objective natu...
In this paper, we investigate the dynamics of coded information in a single Cooper pair interacting with a single Cavity mode. The effect of the relative ratio of Josephson junction capacity and the gate capacities on the purity, coherent vectors and the entropy of the traveling Cooper pair are investigated. The exchange information between the env...
Grid scheduling is one of the prime challenges in grid computing. Reliability, efficiency (with regard to time utilization), effectiveness in resource usage, as well as robustness tend to be the demanded features of Grid scheduling systems. A number of algorithms have been designed and developed in order to make effective Grid scheduling. Project m...
The process of teleport information remotely in presence of an error in the implementation of the local operations as CNOT and Hadamard gate at the sending station is discussed. Through the control of the laboratory equipment the errors in the achieving the local operations could be resisted. The imperfect CNOT gates performance could be improved a...
Free cooling has become widely used in the area of computer room thermal control, especially where the temperature constraint can be relaxed. However, in tropical regions, such as Malaysia, free cooling cannot be applied all of the time. This paper presents a strategy for grids that allows jobs to be executed on resources that are free cooled. The...
We investigate the linear entropy of a degenerate Raman process involving two degenerate Rydberg energy levels of an atom interacting with a cavity field. It is shown that a long living entanglement can be obtained for particular initial state settings. We demonstrate how these states can be observed experimentally and study the feasibility of the...
Stroke is a major cause of severe physical disability, leading into a variety of impairments. In general, stroke rehabilitation is a process which requires intensive direct physical therapy and is usually guided by physiotherapists. The long and intensive therapy sessions often results in patients losing the motivation to continue with the therapy,...
The availability of different flavor of processor architecture coupled with computer codes of various nature poses a discreet challenge to the programmers in forms of code optimization. Programmers need to contemplate on optimization during pre and post implementation to take advantage of the hardware given for a specific nature of the code. To com...
The availability of different flavor of processor architecture coupled with computer codes of various nature poses a discreet challenge to the programmers in forms of code optimization. Programmers need to contemplate on optimization during pre and post implementation to take advantage of the hardware given for a specific nature of the code. To com...
A Grid is a computational system consisting of a large number of geographically distributed and heterogeneous resources. Job scheduling is the key component of a Grid, and plays an important role in the efficient and effective execution of various kinds of scientific and engineering applications. This paper presents a comparative performance analys...
![TABLE 1 JAVA PROCESSORS [13]](profile/Hitham-Alhussian-2/publication/261260545/figure/tbl1/AS:669071477587974@1536530479701/JAVA-PROCESSORS-13_Q320.jpg)
As embedded and real-time systems are becoming more and more Internet-enabled with a plethora of processors, operating systems, and peripheral device types; the line between general purpose programming and low-level specialized programming is now blurring and systems that used to be specialized and low-level become larger and more complex. The Java...
This paper presents a case study that observes usability issues of a system currently used in the main control room of an oil refinery plant. Poor usability may lead to poor decision makings on a system, which in turn put thousands of lives at risk, and contributes to production loss, environmental impact and millions dollar revenue loss. Thus, a c...
The demand of Unmanned Aerial Vehicle (UAV) to monitor natural disasters extends its use to multiple civil missions. While the use of remotely control UAV reduces the human casualties’ rates in hazardous environments, it is reported that most of UAV accidents are caused by human factor errors. In order to automate UAVs, several approaches to path p...
The problems which are NP-complete in nature are always attracting the computer scientists to develop some heuristic algorithms, generating optimal solution in time-space efficient manner compared to the existing ones. Generating the chromatic number of a graph in reasonable time belongs to the same category, where the algorithm designers are tryin...
Large-scale engineering simulation typically requires resources beyond that of a single workstation. On the other hand, given a large number of workstations, servers and personal computers, due to the communication cost involved, it may make no sense to use all of the available resources to run a single simulation. In fact, in such a situation, it...
A grid is a large-scale, heterogeneous, dynamic collection of independent computers, geographically distributed and interconnected with high speed networks. The resources making up a grid need to be managed to provide a good quality of service. Grid scheduling is a vital component of a Computational Grid infrastructure. Typically scheduling challen...
Compiler flags exist to provide option for the software developer to dictate certain parameter to the compiler. Such parameters provide hints to the compiler on how to handle certain portion of the source code. In the realm of optimization, compiler flags provide the fastest way to speed up a program. The right combination of flags will provide sig...
The demand of Unmanned Aerial Vehicle (UAV) to monitor natural disasters extends its use to multiple civil missions. While the use of remotely control UAV reduces the human casualties' rates in hazardous environments, it is reported that most of UAV accidents are caused by human factor errors. In order to automate UAVs, several approaches to path p...
Adopting the framework of two-coupled superconducting charges model, we
discussed the information entropy of two qubits initially prepared in a mixed
state and allowed to interact with their environment. The impact of the
different parameters of the system is explicitly investigated. Present
calculations show that strong mutual entropy is obtained...
The visualization of search space makes it easy to understand the behavior of the Genetic Algorithms (GAs). We proposed a novel way for representation of multidimensional search space of the GA on 2-D graph. This visualization is carried out based on the gene values of the current generation, and user interruption is only required after several gen...
In this paper, we propose to develop an intelligent camera control algorithm for scientific visualization. Intelligent camera
control refers to a path planning algorithm that allows a virtual camera to navigate a scene autonomously. Intelligent camera
overcomes some shortcomings of traditional manual navigation such as the risk of getting lost in t...
Research in underwater acoustic networks has been developed rapidly to support large variety of applications such as mining equipment and environmental monitoring. As in terrestrial sensor networks; reliable data transport is demanded in underwater sensor networks. The energy efficiency of error correction technique should be considered because of...
We consider in this paper the possibility of embedding a quantum search
algorithm within a classical binary search framework. The result appears
promising: taking full advantage of quantum parallelism, we show that it may
actually be possible to search an unstructured list in O(lg(N)), provided we
are willing to restart the quantum search multiple...
Research in underwater acoustic networks has developed quickly to support large variety of applications such as mining equipment and environmental monitoring. As in terrestrial sensor networks; reliable data transport is demanded in underwater sensor networks. The energy efficiency of error correction techniques should be considered because of the...
This paper applied an Interactive Genetic Algorithm (IGA) technique to design an visualization environment for search space. In past IGA works with a small size of population and generations to prevent the user fatigue, in this way small search space is used for evolving solutions. The proposed work is based on the use of objective function for ass...
Interest in soft computing techniques, such as artificial neural networks (ANN) is growing rapidly. Feed-forward back-propagation and radial basis ANN are the most often used applications in this regard. They have been utilized to solve a number of real problems, although they gained a wide use, however the challenge remains to select the best of t...
3D curve drawing is a fundamental operation in the creation and manipulation of surfaces and 3D models. Although techniques
for specifying 3D curves using 2D input devices have been developed extensively, they are mostly indirect, with the need of
multiple viewpoints or multiple lines to specify a 3D curve. We propose a simple technique to directly...
We introduce in this paper an interface for botanical tree modeling that allows the user to sketch a tree, and then to automatically
reproduce it at various stages of ‘growth’. The technique works by first inferring as best as possible the L-System growth
rule that represent the tree model drawn by the user. The user can then reproduce the tree mod...
This paper proposed an Application Programming Interface (API) for sketch-based user interface (UI). A recent research direction in modeling interface is to automate or assist the sketch-to-3D translation process. This trend, known as sketch-based interface for modeling, is motivated by the ease of sketching and the ability of human viewers to imbu...
In computer graphics, L-System is widely used to model artificial plants structures and fractals. The Genetic Algorithm (GA)
is the most popular form of Evolutionary Algorithms. This paper examines a method for automatic plant modeling which is based
on an integration of GA and Parametric L-System using appropriate fitness function. The approach is...
This paper presents a feed-forward Artificial Neural Network (ANN) model for prediction of isolate and normal pentene of debutanizer catalytic reforming unit. Temperature, reflux flow, and flow rate are used as input variables to the network. Isolate pentene (iC 5 ), and normal pentene (nC 5 ) are employed as the output variable. About 500 field da...
A point data set is a set of independent point samples that are typically acquired from a D scanning process. We are interested in detecting and rendering silhouettes in such data set, for the purpose of Non-Photorealistic Rendering (NPR). Traditionally, work on silhouette extraction and rendering tends to assume a polygonal mesh input, where conne...
Photo Based Walkthrough' is a real time walkthrough system in a virtual environment constructed from photo images. Since actual photographs are used, the virtual environment can achieve unparalleled realism. On the other hand, geometry-based rendering system is very time consuming to be constructed especially for a large environment with complex li...
We introduce in this paper an interface for modeling botanical trees that we term a sketch-and-spray interface. In using the
interface, a user would sketch out various types of strokes to construct the main structures of a tree. A user could use a
branch stroke to draw a single branch, a leaf stroke to draw a single leaf or a stem of leaves, or a c...
Questions
Questions (4)
I'm looking for a small TSP instance (no more than a few thousand cities) that draws out the worst case factorial performance in Concorde (https://neos-server.org/neos/solvers/co:concorde/TSP.html). So far, it seems to break at nothing - the results returned in seconds or minutes. The theoretical exponential worst case performance should be noticable, even on Concorde, and even if N is in the range of just hundreds or a couple thousands.
All the small datasets available online (eg. http://www.math.uwaterloo.ca/tsp/data/index.html, http://www.tsp.gatech.edu/data/index.html) seem to be too easy, already long solved to optimality. And while there are work that proposed methods to generates difficult instances (eg. https://link.springer.com/chapter/10.1007/978-3-642-20525-5_1), I wish to know if there is already a dataset of hard, unsolved (yet small) instances available, so that I can focus on my actual research and not have to implement and experiment with published instance generation methods.
A similar question has been asked before, back in 2013: Where to find a set of hard Traveling Salesman Problems (with known solutions/approximations)?. But I find the answers unsatisfactory; besides what I need is a relatively small TSP instance - one where the difficulty is due to the structure rather than the size.
Suppose I am given a motion data file (say AMC) that is without the translation/rotation of the overall skeleton. If I only know the joint angles, how do I compute the overall translation and orientations of the figure? I have some idea. To calculate walking distance for example, I would need to calculate the stride length (how to determine a stride?) and the number of strides per unit time. To calculate the body orientation, I should compute the length and orientation of the leg limb at the point of foot-ground contact, and to calculate the body position during the flight phase (in running), I will need the velocity of the feet upon take-off and compute the force. But I'm interested to know if there's certain subtlety or if there is is some explanation or example calculations anywhere. Thanks.
