• Journal of the Korea Society for Simulation
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• v.32 no.4
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• pp.11-18
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• 2023

This study analyzes the effect of a handshake location of an AS/RS with twin cranes for mixed-model production line at an automobile plant. Implementing a handshake operation has the advantage for preventing route interference between twin cranes that operate without crossing into each other's working areas. However the handshake operation requires additional unloading and loading processes to retrieve assembly parts beyond the handshake area. Therefore the decision regarding the handshake location is crucial to improve efficiency of storage and retrieval operations. Simulation results show that the handshake operation with the optimal handshake location reduces the average response time of storage requests to 87% compared to non-handshake operation.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.4
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• pp.504-508
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• 2002

The effects of fetal number (single or twin) on blood glucose and plasma NEFA during pregnancy and around parturition were studied on ten Alpine ${\times}$ Beetal crossbred goats in their first to third lactation. The animals were divided in-groups 1(carrying single fetus, n=4) and 2(twin fetus, n=6). The samples were drawn on day1 after estrus and then at 14 days interval (fortnight) for 10 fortnights. Around parturition the samples were taken on days -20, -15, -10, -5, -4, -3, -2, -1 prior to kidding and on day 0 and +1, +2, +3, +4, +5, +10, +15, +20 days post kidding. In twin bearing goats the blood glucose concentration continued to increase from 1st until 4th fortnight and thereafter gradually decline from 5th upto 8th fortnight. In single bearing goats there was increase in levels from 2nd upto 4th fortnight and thereafter it declined from 5th uptill 9th fortnight. The difference in sampling interval was highly significant (p<0.01) in both the groups. However the values were higher in single than in twin bearing goats. The plasma NEFA concentration was low in both the groups' upto 4th fortnight and thereafter it is continuously increased upto 9th fortnight. During prepartum period the blood glucose was higher in single than in twin bearing goats. The values were minimum on the day of kidding in both the groups. During postpartum period the values were significantly (p<0.01) higher in twin than in single fetus bearing goats. The plasma NEFA was significantly (p<0.05) higher in twin than in single fetus bearing goats. The blood glucose and plasma NEFA concentration can be used as index of nutritional status during pregnancy and around parturition in goats.

• Journal of Distribution Science
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• v.14 no.7
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• pp.53-61
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• 2016

Purpose - The production efficiency of agricultural crops has been the subject of numerous studies in the field of agricultural economics. This study examines the production efficiency of emerging vineyards in the 14 northern U.S. states and aims to understand raw input and managerial factors affecting the grape production with focusing on the effect of farm size. Research design, data, and methodology - Using a unique survey dataset that was collected from 176 vineyards in 2012, we employed data envelopment analysis (DEA) for estimation of production efficiency in individual vineyards. Production efficiency is regressed on various input and managerial covariates to understand factors influencing the productivity. Results - Although there exists positive correlation between the farm size and productivity of vineyards in Northern U.S. states, we find negative relationship when the farm size is instrumented by the additional farm size expansion indicator. The negative effect is more pronounced for the recently established vineyards. Conclusions - This study suggests that there needs to be adequate managerial improvements for emerging vineyards in northern states for the achievement of increased productivity.

• Asian-Australasian Journal of Animal Sciences
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• v.15 no.3
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• pp.346-351
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• 2002

The effect of fetal number (single or twin) on plasma concentrations of progesterone, estradiol $17{\beta}$, cortisol, prolactin, growth hormone, triiodothyronine, thyroxine and insulin around parturition (periparturient period) were studied on ten $Alpine{\times}Beetle$ crossbred goats in their first to third lactation. The hormone profiles were studied on days -20, -15, -10, -5, -4, -3, -2, -1 prior to kidding and on day 0 and +1, +2, +3, +4, +5, +10, +15, +20 days postkidding. Plasma progesterone levels were significantly (p<0.01) higher in twin bearing goats comparison to single bearing goats during all the days of sampling. The decline in progesterone concentration from day 20 to day 1 before kidding was 56% in twin and 42% in single bearing goats. In single bearing goats plasma estradiol $17{\beta}$ was significantly (p<0.01) higher during prekidding days compared to twin bearing goats. The level of estradiol $17{\beta}$ was highest on the day of kidding in both the groups. The plasma prolactin level in twin bearing goats from day 10 to day 1 prepartum was higher as compared to single fetus bearing goats. However there was abrupt increase in prolactin level on the day of kidding in both the groups. The plasma growth hormone levels were significantly (p<0.01) higher in twin compared to single bearing goats. On the day of kidding growth hormone levels were significantly (p<0.01) higher in twin as compared to single bearing goats (1.40 vs. 0.95 ng/ml). In twin bearing goats plasma cortisol values from day 5 till the day of kidding remained elevated and the levels on the day of kidding was significantly highest in both the groups. The levels of triiodothyronine ($T_3$) were significantly higher (p<0.01) during all the periods of sampling in single compared to twin bearing goats. Plasma thyroxine ($T_4$) was significantly (p<0.01) lower in twin compared to single bearing goats. In single bearing goats plasma insulin levels were significantly (p<0.01) higher than twin bearing goats during prepartum period however during post partum period the levels in both the groups remained similar. It can be concluded that number of fetuses is having significant influence on the hormone profile during periparturient period.

• Journal of the Korean Society of Industry Convergence
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• v.26 no.3
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• pp.471-481
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• 2023

Digital twin is considered as a key technology of industry 4.0, thus being essential for the future of industrial production. Despite the significance, a systematic analysis of its technological landscape is lacking. This study aims to investigate the technological development trends and newly emerging technological convergence opportunities in the domain of digital twin by exploiting patent information derived from U SPTO. For this purpose, this study visualized and predicted the convergence dynamics among patent classification codes by adopting patent co-classification analysis and link prediction approach. The findings show that the number of digital twin-related patent applications has increased significantly since 2018. The CPC code G06F showed the highest eigenvector centrality, while G05B was characterized by highest betweenness centrality. According to the predictive model, 41 novel links were revealed, acting as potential technology convergence opportunities. These links were then categorized into 11 different domains. The most dominant category was "digital data processing and artificial intelligence", which could play a foundational role in the diffusion of digital twin technology. The presence of digital twin technology is dominant in manufacturing, but its applications are expected to expand, including "climate change", "healthcare" and "aerospace engineering". The derived insights can support R&D managers and policy makers in formulating R&D strategies and directing future R&D investment decisions.

• Journal of Biosystems Engineering
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• v.19 no.1
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• pp.42-49
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• 1994

Texturization of plant protein means the physical or chemical recomposition method of plant protein damaged during the extracting process of soybean oil. As a stable protein supplement, substituted for meat, needs of texturized products have been increased. Twin screw extruder is a very effective tool for texturization process as a physical method. This research, using defatted soy flour as raw material and twin screw extruder manufactured in domestic, showed that plant protein was texturized successfully on the operating conditions of barrel temperature of $120{\sim}140^{\circ}C$, material feed rate of 30~36kg/hr and water content of 20~25%. It also showed that the shape of die affected the texturization continuity.

• Fashion & Textile Research Journal
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• v.12 no.3
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• pp.347-353
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• 2010

The purpose of this study was to examine the appropriate surplus of clothing for a suitable basic bodice pattern of Male Sports Athletes by using the 3D virtual twin and virtual garment simulation system. The results were as follows; 1. By using 3D virtual twin and garment simulation, new bodice pattern considered male sports athletes was development. The basic numerical formula were as follows ; surplus of chest girth=9, surplus of back length=1, armhole depth=back length/4+13, half back width=chest girth/5+2.5, front chest width=chest girth/5+3. 2. Wearing test by 3D virtual garment simulation system was useful to evaluate wearing outline, surplus of clothes and garment space. Also it estimated more highly than existing pattern in silhouette and ease amount, confirming that new bodice pattern is appropriate for the male sports athletes. New bodice pattern was evaluated to allow proper space length of chest and waist. Virtual models production through 3D body scan data, pattern draft and virtual garment digital program were applied to prototypic design method so as to enhance the fitness of ready-made garments. This study is expected to serve as one of important basic data for ensuing studies that may utilize 3D Virtual Garment Simulation System with 2D patterns, and also for future 3D Pattern Production Program development.

• Korean Chemical Engineering Research
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• v.59 no.3
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• pp.305-315
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• 2021

An intermeshing corotating twin screw extruder is mainly used for compounding polymeric materials. Twin screw extruder can adopt modular-type screw configurations, which directly controls the quality and productivity of the products. The types, shapes, and specifications of the screw and kneading elements are summarized, and the effects of screw configuration on the processabiliy of the materials are discussed. The principles of screw configuration universally applied to mass production of general-purpose resins are explained, and the guidelines of screw combination according to the roles of feeding, melt mixing, and metering zones are listed. The strategies of screw combination suitable for various cases, such as side feeding of liquid additives or inorganic fillers, reactive extrusion, devolatilization process, production of products requiring bright color and transparency, and processing of materials with low apparent specific gravity, are presented.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.26 no.3B
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• pp.253-262
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• 2006

The present paper presents a direct numerical simulation of turbulent flows in a compound open-channel. Mean flows and turbulence structures are provided, and they are compared with the numerical data and measured data available in the literature. The simulated results show that twin vortices are generated near the juncture of the main channel and the floodplain and their maximum magnitude is about 5% of bulk streamwise velocity. At the juncture, the simulated wall shear stress becomes the maximum unlike the experimental data. A quadrant analysis shows that both sweeps and ejections become the main contributor to production of Reynolds shear stresses. A conditional quadrant analysis reveals that the directional tendency of dominant coherent structures determines the production of Reynolds shear stress and the pattern of twin vortices.

• 한국신재생에너지학회:학술대회논문집
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• 2011.05a
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• pp.186.1-186.1
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• 2011

Most of waste plastics including waste vinyls have been recycled up to about 50% of waste production, 4.5 million ton per year in 2009. To fundamentally increase the recycled amounts of waste plastics to waste production, the energy utilization of waste plastics is inevitable. But the contents of PVC included in waste plastics can limit the use as a RPF and make the air pollutants such as HCl and dioxin when it burns in the combustion system. Accordingly the source dechlorination by using heating method can be applied to make low contents of HCl as less than 0.6%. In this study the twin screw reactor using heat medium was used for the source dechlorination. As results of study, it was considered that this system is effective for the industrilal application.