• Fashion & Textile Research Journal
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• v.25 no.3
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• pp.386-397
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• 2023

In this study, the efficacy of ultrasonic washing in cotton and wool fabrics was compared and evaluated against conventional washing in terms of cleaning properties and fabric deformation. Factors such as washing temperature, time, liquid ratio, and detergent concentration were kept varied, and the cleaning properties of sebum-soiled fabrics were assessed using different detergents such as alcohol ethoxylate, linear alkylbenzenesulfonate, and IEC 60456 Reference Detergent A^*. In addition, the effects and emulsification power of enzymes and oxygen bleach were examined. To compare the cleaning properties with general washing, a launder-O-meter was used. To investigate fabric deformation during the washing process, the loosening test cloth, shrinkage test cloth, and mechanical strength test cloth were compared between ultrasonic washing machines and household drum washing machines. The results indicate that ultrasonic washing exhibits superior cleaning properties than launder-O-meter when the temperature is low and the washing time is short. Furthermore, there is less deformation and damage during the washing process. It was also observed that the activity of the detergent increases when ultrasonic waves are applied to the washing process. Considering the increasing tendency to pursue convenience and simplicity in clothing management as well as the anticipated commercialization of smart clothing with built-in electric circuits, ultrasonic laundry could serve as a new alternative to existing laundry methods.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.3
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• pp.318-322
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• 2015

In the modern pork industry, selection of high intramuscular fat (IMF) in pigs is necessary to improve pork quality. Ultrasound has been used previously to predict subcutaneous fat thickness and IMF in the longissimus muscles of line pigs and Real-time ultrasound has also been reported as a reliable method for estimating IMF in live pigs. So we estimate the correlation between meat quality traits and IMF percentage to investigate the possibility of utilizing real-time ultrasound technology for predicting IMF percentage in line pigs to improve pork quality. The genetic and phenotypic correlations for chemical intramuscular fat (CIMF) and ultrasound intramuscular fat (UIMF) were estimated to be 0.75 and 0.76, respectively. These results suggest that genetic factors strongly influence meat quality. The genetic and phenotypic correlation between UIMF and CIMF were 0.75, 0.76, respectively. The heritability of UIMF and CIMF were 0.48 and 0.50, respectively. So we concluded that CIMF can be replaced with UIMF and Ultrasound machines can be used to test IMF in live swine. In future, UIMF can be utilized to improve pork quality as an alternative to CIMF.

• Journal of Power Electronics
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• v.9 no.5
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• pp.781-790
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• 2009

This paper presents an implementation of a direct active and reactive power control for a doubly fed induction generator (DFIG), which is applied to a wind generation system as an alternative to the classical field-oriented control (FOC). The FOC has a complex control structure that consists of a current controller, a power controller and frame transformations. The performance of the FOC depends highly on parameter variations of the rotor and stator resistances and the inductances. The proposed direct power control (DPC) method produces a fast and robust power response without the need of complex structure and algorithms. One drawback, however, is its high power ripple during a steady state. In this paper, active and reactive power controllers and space-vector modulation (SVM) are combined to replace hysteresis controllers used in the original DPC drive, resulting in a fixed switching frequency of the power converter. Simulation results with the FOC and DPC for a 3kW DFIG are given and discussed, and the experimental results of a test involving identical machines are presented to illustrate the feasibility of the proposed control strategy.

• Journal of KSNVE
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• v.9 no.4
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• pp.643-651
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• 1999

A brief description of the current technology (contact-start-stop) employed in most of today's hard disk drive is presented. The dynamics and head/disk interactions during a start/stop process are very complicated and no one has been able to accurately model the interactions. Thus, the head/disk interface that meets the start/stop durability and stiction requirements are always developed statistically. In arriving at a solution. many sets of statistical tests are run by varying several parameters. such as, the carbon overcoat thickness. lubricant thickness. disk surface roughness, etc. Consequently, the cost associated III developing an interface could be significant since the outcome is difficult to predict. An alternative method known as Load/Unload technology alters the problem set. such that. the start/stop performance can be designed in a predictable manner. Although this techno¬logy offers superior performance and significantly reduces statistical testing time, it also has some potential problems. However. contrary to the CSS technology. most of the problems can be solved by design and not by trial and error. One critical problem is that of head/disk contacts during the loading and unloading processes. These contact can cause disk and slider damage because the contacts are likely to occur at high disk speeds resulting in large friction forces. Use of glass substrate disks also may present problems if not managed correctly. Due to the low thermal conductivity of glass substrates. any head/disk contacts may result in erasure due to frictional heating of the head/disk interface. In spite of these and other potential problems. the advantage with L/UL system is that these events can be understood. analyzed. and solved in a deterministic manner.

• Journal of the Korea Safety Management & Science
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• v.18 no.1
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• pp.75-82
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• 2016

According to the statistics, occupational fatal injuries by the fork lifts were about 30 per year in whole industrial. Fork lifts are widely used in various parts of industries to improve the efficiency of the work. In this study, the current regulations to be adequate in industrial site have to be renew in order to prevent the fatal injuries by the fork lifts. Fatal injury analysis were conducted with several accident cases by the fork lifts. For each accident, the causes of the injuries were examined and proper safety measures were proposed. In this study, the fork lift showed a high fatality rate in industrial accidents and no detailed cause analysis of fatal accidents was conducted in terms of unsafe acts or conditions. First, fork lifts were the highest of the machines caused the accidents. In order to prevent fatal injuries by the fork lifts, the tarket was manufacturing industry. Second, the order of the cause of cognitive engineering agenda in the manufacture industrial was visibility, responsibility and affordance, and revision of acts was proposed. Third, there was not a lots of different points of human error between occurrence types and business sizes. Forth, number of fatalities by the attacker was more than by the inducer.

• Journal of Institute of Control, Robotics and Systems
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• v.5 no.5
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• pp.614-621
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• 1999

In this paper, the analytical appproaches are presented for jointly determining the profit-miximizing configuration of the fault-tolerance real time modular cell manufacturing system. The transient(time-dependent) analysis of Markovian models is firstly applied to modular cell manufacturing system from a performability viewpoint whose modeling advantage lies in its ability to express the performance that truly matters - the user's perception of it - as well as various performance measures compositely in the context of application. The modular cells are modeled with hybrid decomposition method and then availability measures such as instantaneous availability, interval availability, expected cumulative operational time are evaluated as special cases of performability. In addition to this evaluation, sensitivity analysis of the entire manufacturing system as well as each machining cell is performed, from which the time of a major repair policy and the optimal configuration among the alternative configurations of the system can be determined. Secondly, the recovery policies from the machine failures by computing the minimal number of redundant machines and also from the task failures by computing the minimum number of tasks equipped with detection schemes of task failure and reworked upon failure detection, to meet the timing requirements are optimized. Some numerical examples are presented to demonstrate the effectiveness of the work.

• 한국전산유체공학회:학술대회논문집
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• 2007.04a
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• pp.153-158
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• 2007

Since the introduction of Nanoimprint in the mid-1990s, Nanoimprint lithography, a low-cost, non-convential method, has been the dominant lithography technology that guarantees high-throughput patterning of nanostructures. Based on the mechanical embossing mechanism, Nanoimprint lithography creates the nanopatterns on the polymer material cast on the substrate. In essence, the process needs nanofabrication equipment for printing with the adequate control of temperature, pressure and control of parallels of the stamp and substrate. This article introduce the possibility and reality of the thermal control on the hot plate using a CFD code. Numerical computation has been conducted for assessing the feasibility of a hot plate($120{\times}120\;mm2$). PID control is adopted to ensure high temperature uniformity in several zones. Parallel experiments have also been performed for verifying thermal performance. Not only show the results the optimum number of thermocouples related to controllers but also suggest that the thermal simulation using a CFD code would be an alternative method to design and develop the thermal control equipment in the financial aspect.

• Transactions of the Korean Society of Mechanical Engineers A
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• v.20 no.1
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• pp.14-23
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• 1996

Scheduling jobs effectively under consideration of actual loads on machines is one of the most complicated tasks in production control. The complexity of the finite capacity scheduling often makes the conventional methods of industrial engineering fail. As an alternative, Knowledge-based approaches to job-shop scheduling have been evolved recently. This paper presents a blackboard- based scheduling expert system which combines knowledge-based scheduling with interactive scheduling. It is shown to be possible to generate the feasible schedule within a reasonable time. Flexible reaction management is also possible while keeping the changes in the generated schedule to the minimal and adjusting the schedule to tardy operations or working environmental changes. The system is equipped with a rule base with heuristics for handling conflicted event. A case study applying the implemented system is described.

• Journal of KIISE:Computer Systems and Theory
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• v.27 no.6
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• pp.558-566
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• 2000

Object recognition is a challenging application for high-performance computing. Currently, the superscalar architecture dominates todays microprocessor marketplace. As more transistors are integrated onto larger die, however, an on-chip multiprocessor is regarded as a promising alternative to the superscalar microprocessor. This paper examines the behavior of the object recognition on the on-chip multiprocessor, which will be employed in general-purpose parallel machines. To obtain the performance characteristics of the microprocessor, a program-driven simulator and its programming environment were developed. The simulation results showed that the on-chip multiprocessor can exploit thread level parallelisms effectively and offer a promising architecture for the object recognition application.

• Journal of the Korea Safety Management & Science
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• v.6 no.4
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• pp.155-170
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• 2004

Among the semiconductor If-chips, unlike memory chips, a majority of Application Specific IC(ASIC) products are produced by customer orders, and meeting the customer specified due date is a critical issue for the case. However, to the one who understands the nature of semiconductor manufacturing, it does not take much effort to realize the difficulty of meeting the given specific production due dates. Due to its multi-layered feature of products, to be completed, a semiconductor product(called device) enters into the fabrication manufacturing process(FAB) repeatedly as many times as the number of the product specified layers, and fabrication processes of individual layers are composed with similar but not identical unit processes. The unit process called photo-lithography is the only process where every layer must pass through. This re-entrant feature of FAB makes predicting and planning of due date of an ordered batch of devices difficult. Parallel machines problem in the photo process, which is bottleneck process, is solved with restricted roll out algorithm. Roll out algorithm is a method of solving the problem by embedding it within a dynamic programming framework. Restricted roll out algorithm Is roll out algorithm that restricted alternative states to decrease the solving time and improve the result. Results of simulation test in condition as same as real FAB facilities show the effectiveness of the developed algorithm.