Abstract: This paper mathematically analyses the varying
magnitude of production loss, which may occur due to idle time (inprocess
waiting time and traveling time) on a linear walking worker
assembly line. Within this flexible and reconfigurable assembly
system, each worker travels down the line carrying out each
assembly task at each station; and each worker accomplishes the
assembly of a unit from start to finish and then travels back to the
first station to start the assembly of a new product. This strategy of
system design attempts to combine the flexibility of the U-shaped
moving worker assembly cell with the efficiency of the conventional
fixed worker assembly line. The paper aims to evaluate the effect of
idle time that may offset the labor efficiency of each walking worker
providing an insight into the mechanism of such a flexible and
reconfigurable assembly system.
Abstract: For decades financial economists have been attempted to determine the optimal investment policy by recognizing the option value embedded in irreversible investment whose project value evolves as a geometric Brownian motion (GBM). This paper aims to examine the effects of the optimal investment trigger and of the misspecification of stochastic processes on investment in real options applications. Specifically, the former explores the consequence of adopting optimal investment rules on the distributions of corporate value under the correct assumption of stochastic process while the latter analyzes the influence on the distributions of corporate value as a result of the misspecification of stochastic processes, i.e., mistaking an alternative process as a GBM. It is found that adopting the correct optimal investment policy may increase corporate value by shifting the value distribution rightward, and the misspecification effect may decrease corporate value by shifting the value distribution leftward. The adoption of the optimal investment trigger has a major impact on investment to such an extent that the downside risk of investment is truncated at the project value of zero, thereby moving the value distributions rightward. The analytical framework is also extended to situations where collection lags are in place, and the result indicates that collection lags reduce the effects of investment trigger and misspecification on investment in an opposite way.
Abstract: Thermochemcial characteristics of powder fabricated
using oxidation treatment of spent PWR fuel and SIMFUEL were
evaluated for recycling of spent fuel such as DUPIC process.
Especially, the influence of spent fuel burn-ups on the powder
fabrication characteristics was experimentally evaluated, ranging from
27,300 to 65,000 MWd/tU. Densities of powder manufactured from an
oxidation, OREOX and the milling processes at the same process
conditions were compared as a function of the fuel burn-ups
respectively. Also, based on chemical analysis results, homogeneity of
fissile elements in oxidized powder was confirmed.
Abstract: A new secure knapsack cryptosystem based on the
Merkle-Hellman public key cryptosystem will be proposed in this
paper. Although it is common sense that when the density is low, the
knapsack cryptosystem turns vulnerable to the low-density attack. The
density d of a secure knapsack cryptosystem must be larger than
0.9408 to avoid low-density attack. In this paper, we investigate a
new Permutation Combination Algorithm. By exploiting this
algorithm, we shall propose a novel knapsack public-key cryptosystem.
Our proposed scheme can enjoy a high density to avoid the
low-density attack. The density d can also exceed 0.9408 to avoid
the low-density attack.
Abstract: As many scientific applications require large data processing, the importance of parallel I/O has been increasingly recognized. Collective I/O is one of the considerable features of parallel I/O and enables application programmers to easily handle their large data volume. In this paper we measured and analyzed the performance of original collective I/O and the subgroup method, the way of using collective I/O of MPI effectively. From the experimental results, we found that the subgroup method showed good performance with small data size.
Abstract: A multi-block algorithm and its implementation in two-dimensional finite element numerical model CCHE2D are presented. In addition to a conventional Lagrangian Interpolation Method (LIM), a novel interpolation method, called Consistent Interpolation Method (CIM), is proposed for more accurate information transfer across the interfaces. The consistent interpolation solves the governing equations over the auxiliary elements constructed around the interpolation nodes using the same numerical scheme used for the internal computational nodes. With the CIM, the momentum conservation can be maintained as well as the mass conservation. An imbalance correction scheme is used to enforce the conservation laws (mass and momentum) across the interfaces. Comparisons of the LIM and the CIM are made using several flow simulation examples. It is shown that the proposed CIM is physically more accurate and produces satisfactory results efficiently.
Abstract: The rapid improvement of the microprocessor and network has made it possible for the PC cluster to compete with conventional supercomputers. Lots of high throughput type of applications can be satisfied by using the current desktop PCs, especially for those in PC classrooms, and leave the supercomputers for the demands from large scale high performance parallel computations. This paper presents our development on enabling an automated deployment mechanism for cluster computing to utilize the computing power of PCs such as reside in PC classroom. After well deployment, these PCs can be transformed into a pre-configured cluster computing resource immediately without touching the existing education/training environment installed on these PCs. Thus, the training activities will not be affected by this additional activity to harvest idle computing cycles. The time and manpower required to build and manage a computing platform in geographically distributed PC classrooms also can be reduced by this development.
Abstract: Vickers indentation is used to measure the hardness
of materials. In this study, numerical simulation of Vickers
indentation experiment was performed for Diamond like Carbon
(DLC) coated materials. DLC coatings were deposited on stainless
steel 304 substrates with Chromium buffer layer using RF Magnetron
and T-shape Filtered Cathodic Vacuum Arc Dual system The
objective of this research is to understand the elastic plastic
properties, stress strain distribution, ring and lateral crack growth and
propagation, penetration depth of indenter and delamination of
coating from substrate with effect of buffer layer thickness. The
effect of Poisson-s ratio of DLC coating was also analyzed. Indenter
penetration is more in coated materials with thin buffer layer as
compared to thicker one, under same conditions. Similarly, the
specimens with thinner buffer layer failed quickly due to high
residual stress as compared to the coated materials with reasonable
thickness of 200nm buffer layer. The simulation results suggested the
optimized thickness of 200 nm among the prepared specimens for
durable and long service.
Abstract: In-vitro mouse co-culture of E14 embryonic stem cells
(ESCs) and OP9 stromal cells can recapitulate the earliest stages of
haematopoietic development, not accessible in human embryos,
supporting both haemogenic precursors and their primitive
haematopoietic progeny. 1α, 25-Dihydroxy-vitamin D3 (VD3) has
been demonstrated to be a powerful differentiation inducer for a wide
variety of neoplastic cells, and could enhance early differentiation of
ESCs into blood cells in E14/OP9 co-culture. This study aims to
ascertain whether VD3 is key in promoting differentiation and
suppressing proliferation, by separately investigating the effects of
VD3 on the proliferation phase of the E14 cell line and on stromal
OP9 cells.The results showed that VD3 inhibited the proliferation of
the cells in a dose-dependent manner, quantitatively by decreased cell
number, and qualitatively by alkaline-phosphatase staining that
revealed significant differences between VD3-treated and untreated
cells, characterised by decreased enzyme expression (colourless
cells). Propidium-iodide cell-cycle analyses showed no significant
percentage change in VD3-treated E14 and OP9 cells within their G
and S-phases, compared to the untreated controls, despite the
increased percentage of G-phase compared to the S-phase in a dosedependent
manner. These results with E14 and OP9 cells indicate that
adequate VD3 concentration enhances cellular differentiation and
inhibits proliferation. The results also suggest that if E14 and OP9
cells were co-cultured andVD3-treated, there would be furtherenhanced
differentiation of ESCs into blood cells.
Abstract: One of object oriented software developing problem
is the difficulty of searching the appropriate and suitable objects for
starting the system. In this work, ontologies appear in the part of
supporting the object discovering in the initial of object oriented
software developing. There are many researches try to demonstrate
that there is a great potential between object model and ontologies.
Constructing ontology from object model is called ontology
engineering can be done; On the other hand, this research is aiming to
support the idea of building object model from ontology is also
promising and practical. Ontology classes are available online in any
specific areas, which can be searched by semantic search engine.
There are also many helping tools to do so; one of them which are
used in this research is Protégé ontology editor and Visual Paradigm.
To put them together give a great outcome. This research will be
shown how it works efficiently with the real case study by using
ontology classes in travel/tourism domain area. It needs to combine
classes, properties, and relationships from more than two ontologies
in order to generate the object model. In this paper presents a simple
methodology framework which explains the process of discovering
objects. The results show that this framework has great value while
there is possible for expansion. Reusing of existing ontologies offers
a much cheaper alternative than building new ones from scratch.
More ontologies are becoming available on the web, and online
ontologies libraries for storing and indexing ontologies are increasing
in number and demand. Semantic and Ontologies search engines have
also started to appear, to facilitate search and retrieval of online
ontologies.
Abstract: Developing a supply chain management (SCM) system is costly, but important. However, because of its complicated nature, not many of such projects are considered successful. Few research publications directly relate to key success factors (KSFs) for implementing a SCM system. Motivated by the above, this research proposes a hierarchy of KSFs for SCM system implementation in the semiconductor industry by using a two-step approach. First, the literature review indicates the initial hierarchy. The second step includes a focus group approach to finalize the proposed KSF hierarchy by extracting valuable experiences from executives and managers that actively participated in a project, which successfully establish a seamless SCM integration between the world's largest semiconductor foundry manufacturing company and the world's largest assembly and testing company. Future project executives may refer the resulting KSF hierarchy as a checklist for SCM system implementation in semiconductor or related industries.
Abstract: Nowadays, many manufacturing companies try to
reinforce their competitiveness or find a breakthrough by considering
collaboration. In Korea, more than 900 manufacturing companies are
using web-based collaboration systems developed by the
government-led project, referred to as i-Manufacturing. The system
supports some similar functions of Product Data Management (PDM)
as well as Project Management System (PMS). A web-based
collaboration system provides many useful functions for collaborative
works. This system, however, does not support new linking services
between buyers and suppliers. Therefore, in order to find new
collaborative partners, this paper proposes a framework which creates
new connections between buyers and suppliers facilitating their
collaboration, referred to as Excellent Manufacturer Scouting System
(EMSS). EMSS plays a role as a bridge between overseas buyers and
suppliers. As a part of study on EMSS, we also propose an evaluation
method of manufacturability of potential partners with six main factors.
Based on the results of evaluation, buyers may get a good guideline to
choose their new partners before getting into negotiation processes
with them.
Abstract: This paper proposes a visual cryptography by random
grids scheme with identifiable shares. The method encodes an image
O in two shares that exhibits the following features: (1) each generated
share has the same scale as O, (2) any share singly has noise-like
appearance that reveals no secret information on O, (3) the secrets can
be revealed by superimposing the two shares, (4) folding a share up
can disclose some identification patterns, and (5) both of the secret
information and the designated identification patterns are recognized
by naked eye without any computation. The property to show up
identification patterns on folded shares establishes a simple and
friendly interface for users to manage the numerous shares created by
VC schemes.
Abstract: The objective of this paper is to design a model of human vital sign prediction for decreasing prediction error by using two states mapping based time series neural network BP (back-propagation) model. Normally, lot of industries has been applying the neural network model by training them in a supervised manner with the error back-propagation algorithm for time series prediction systems. However, it still has a residual error between real value and prediction output. Therefore, we designed two states of neural network model for compensation of residual error which is possible to use in the prevention of sudden death and metabolic syndrome disease such as hypertension disease and obesity. We found that most of simulations cases were satisfied by the two states mapping based time series prediction model compared to normal BP. In particular, small sample size of times series were more accurate than the standard MLP model. We expect that this algorithm can be available to sudden death prevention and monitoring AGENT system in a ubiquitous homecare environment.
Abstract: Cooperative learning has been defined as learners working together as a team to solve a problem to complete a task or to accomplish a common goal, which emphasizes the importance of interactions among members to promote the whole learning performance. With the popularity of society networks, cooperative learning is no longer limited to traditional classroom teaching activities. Since society networks facilitate to organize online learners, to establish common shared visions, and to advance learning interaction, the online community and online learning community have triggered the establishment of web-based societies. Numerous research literatures have indicated that the collaborative learning community is a critical issue to enhance learning performance. Hence, this paper proposes a learning community recommendation approach to facilitate that a learner joins the appropriate learning communities, which is based on k-nearest neighbor (kNN) classification. To demonstrate the viability of the proposed approach, the proposed approach is implemented for 117 students to recommend learning communities. The experimental results indicate that the proposed approach can effectively recommend appropriate learning communities for learners.
Abstract: Resistance of denial of service attacks is a key security requirement in voting protocols. Acquisti protocol plays an important role in development of internet voting protocols and claims its security without strong physical assumptions. In this study firstly Acquisti protocol is modeled in extended applied pi calculus, and then resistance of denial of service attacks is proved with ProVerif. The result is that it is not resistance of denial of service attacks because two denial of service attacks are found. Finally we give the method against the denial of service attacks.
Abstract: In this paper, we present two new one-step iterative
methods based on Thiele-s continued fraction for solving nonlinear
equations. By applying the truncated Thiele-s continued fraction
twice, the iterative methods are obtained respectively. Analysis of
convergence shows that the new methods are fourth-order convergent.
Numerical tests verifying the theory are given and based on the
methods, two new one-step iterations are developed.
Abstract: This paper studies the design of a simple constellation
precoding for a multiple-input multiple-output orthogonal frequency
division multiplexing (MIMO-OFDM) system over Rayleigh fading
channels where OFDM is used to keep the diversity replicas orthogonal
and reduce ISI effects. A multi-user environment with K synchronous
co-channel users is considered. The proposed scheme provides
a bandwidth efficient transmission for individual users by increasing
the system throughput. In comparison with the existing coded
MIMO-OFDM schemes, the precoding technique is designed under
the consideration of its low implementation complexity while providing
a comparable error performance to the existing schemes.
Analytic and simulation results have been presented to show the distinguished
error performance.
Abstract: Helical milling operations are used to generate or
enlarge boreholes by means of a milling tool. The bore diameter can be
adjusted through the diameter of the helical path. The kinematics of
helical milling on a three axis machine tool is analysed firstly. The
relationships between processing parameters, cutting tool geometry
characters with machined hole feature are formulated. The feed motion
of the cutting tool has been decomposed to plane circular feed and
axial linear motion. In this paper, the time varying cutting forces acted
on the side cutting edges and end cutting edges of the flat end cylinder
miller is analysed using a discrete method separately. These two
components then are combined to produce the cutting force model
considering the complicated interaction between the cutters and
workpiece. The time varying cutting force model describes the
instantaneous cutting force during processing. This model could be
used to predict cutting force, calculate statics deflection of cutter and
workpiece, and also could be the foundation of dynamics model and
predicting chatter limitation of the helical milling operations.
Abstract: A novel interpolation scheme to extend usable spectrum
and upconvert in high performance D/A converters is addressed in this
paper. By adjusting the pulse width of cycle and the production circuit
of code, the expansion code is a null code or complementary code that
is interpolation process. What the times and codes of interpolation
decide DAC works in one of a normal mode or multi-mixer mode
so that convert the input digital data signal into normal signal or a
mixed analog signal having a mixer frequency that is higher than the
data frequency. Simulation results show that the novel scheme and
apparatus most extend the usable frequency spectrum into fifth to
sixth Nyquist zone beyond conventional DACs.