• Journal of ILASS-Korea
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• v.14 no.4
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• pp.171-177
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• 2009

This study proposes a new stratified charge system for low emission and ultra lean burn. In order to examine combustion characteristics of the new system, sparkplug with a hole at positive pole and a common CNG injector for injecting fuel were used in this study as injector-type spark plug. The new stratified charge system injects fuel of extremely small quantities and ignites mixture around sparkplug gap. Also, the system was fitted in a visualized constant volume chamber. Then, for analysis of the combustion characteristics, we examined combustion pressure, lean inflammable limit, and visualized combustion flame according to equivalence ratio by comparison with homogeneous charge (HC) method and the new stratified charge (SC) method. As results of this study, in the case of using this system, the propagation speed of initial flame was increased and total combustion period was reduced in the ultra lean burn in the same equivalence ratio. These phenomena occurred clearly under the conditions of lean equivalence ratio. Furthermore, the lean inflammable limit of mixture was extended by using the injector-type spark plug.

• Journal of the Korea Safety Management & Science
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• v.14 no.2
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• pp.147-158
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• 2012

This paper aims to develop a new chain metrics for obtaining lean Overall Equipment Effectiveness(OEE) and present implementation strategy which considers the properties for Total Productive Maintenance(TPM) to reduce machine losses, Performance Analysis and Control(PAC) to reduce labor losses, Lean Production System(LPS) to reduce floor wastes, and Theory of Constraints(TOC) to minimize the problem of Capacity Constrained Resource(CCR). The study reviews the related literatures and reformulates the structure of machine losses, labor losses and field wastes. The research also develops the integrated productivity metrics according to time, units, reliability and maintainability. It is found that the study develops the actual productivity measure in terms of efficiency, effectiveness and standard productivity. In addition to that, it outlines and develops by using the integrated LPS and TPM, lean OEE measures such as Time Based Productivity(TBP), Unit Based Productivity(UBP), and Reliability & Maintainability Based Availability(RMBA). Implication examples are proposed to make it easier and available for practioners to understand the implementation strategies about TPM OEE, lean OEE and TOC OEE. Futhermore related to other studies, the research contributes to create a new chain productivity measures to clear the interrelationship concepts of productivity, efficiency and effectiveness. Moreover the paper develops the enhanced OEE measures by integration of TPM, PAC, LPS and TOC with the perspective of schedule, throughput, reliability, maintainability and availability.

• Physical Therapy Korea
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• v.30 no.1
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• pp.8-14
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• 2023

Background: Excessive hamstring (HS) activation due to the weakness of the gluteus maximus (GM) causes pain in the hip joint. A single-leg deadlift is a hip extensor exercise, especially GM, that includes functional movements in daily life and complex multi-joint training. In single-leg deadlift, the muscle activity depends on the forward trunk lean angle, and it's necessary to study which muscles are used dominantly depending on the angle. Objects: The purpose of this study was to compare the effect on the muscle activity of the GM and HS during single-leg deadlift according to different forward trunk lean angles and the ratio of the GM vs HS (GM/HS). Methods: Twenty-one healthy female participants were recruited. The muscles activities of the GM, HS and the GM/HS ratio were measured through electromyography during single-leg deadlift according to three condition of forward trunk lean angles (30°, 60°, and 90°). Results: The GM and HS activities significantly differed among three conditions (p < 0.05). GM/HS ratio was significantly higher at 30° and 60° of forward trunk lean compared to 90°. Moreover, the GM activity was significantly higher at 60° of forward trunk lean than at 30° (p < 0.05). Conclusion: The single-leg deadlift at 60° of forward trunk lean is a proper GM muscle strengthening exercise.

• Journal of Biomedical Engineering Research
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• v.28 no.5
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• pp.628-635
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• 2007

We studied the effect of vibratory stimulations of different leg muscles, tibialis anterior(TA) and triceps surae(TS), and plantar zones in ten healthy subjects during 1) quiet standing, 2) forward lean of body, 3) backward lean of body, 4) right lean of body, and 5) left lean of body. The experiments were performed on the force platform. The effect of vibration were measured by monitoring the area of COP(Center of pressure) sway. The subjects wore a vibratory stimulation system on foot and ankles and were given the instruction not to resist against the applied perturbations. The results show that all vibratory stimulations to lower limb muscles and plantar zones reduced the COP sway area. This reduction of the COP sway area occurred also in partial vibratory stimulations during quiet standing. In forward lean of body, vibratory stimulations to TA reduced the COP sway area. During backward lean of body, vibratory stimulations to TS reduced the COP sway area. When the subject was tilted right, vibratory stimulations to left plantar zone reduced the COP sway area. During left lean of body, vibratory stimulations to right plantar zone reduced the COP sway area. Thus, the influence of vibratory stimulations to leg muscle and plantar zones differed significantly depending on the lean of body. We suggest that the vibration stimuli from leg muscles and plantar zones could be selectively used to help maintaining postural balance stable.

• Convergence Security Journal
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• v.8 no.1
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• pp.101-108
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• 2008

This research focuses on the process improvement of port logistics by using Lean methodology. On the one hand, we firstly analyze the current situation and weakness of the processes in port logistics, and then re-design the current processes by the principles of Lean discipline. Based on the appropriately changed processes, the improvement scheme of port logistics will be figured out. On the other hand, we construct the port logistics system by implementing the improved processes. The port logistics' processes accomplished in steel company will be further assorted and identified. The relationship of wharves process, operational process, shipping process, construction process, quality process, and purchasing process are also defined. Every process has been improved by Lean Tools in order to analyze the value added or non-value added processes, to improve the service level, and to reduce the cycle time, inventory, changing time, re-working and waste. Based on above, the appropriate environment that is suitable to Lean process of port logistics will be established and the modeling that can help to implement the improvement scheme will be figured out.

• The Korean Journal of Food And Nutrition
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• v.27 no.4
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• pp.650-659
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• 2014

The purpose of this study was to analyze Hanwoo usage in restaurants and to develop menus of lean cut Hanwoo. Restaurant served customers Hanwoo menus, with the exception of broiled or roasted meat, mainly to provide various menus to customers (4.14), due to customer needs (3.87) and utilizing stocks (3.59). On the other hand, the reason for not providing Hanwoo menus, with the exception of broiled or roasted meat was manpower shortage (3.63), lack of popularity (3.58), low profit (3.29), preservation of Hanwoos' original flavors (3.28) and complex cooking methods (3.22). Concomitantly, the restaurant owners' intentions to apply new menus with lean cut Hanwoo was 73.4%, showing an interest in developing new menus and recipes using lean cut Hanwoo suitable to the changing owner awareness of customer health and trends. This study has established a standard for developing cooking methods and developed menus according to classified recipes for lean cut Hanwoo, based on the survey of restaurants' current status of using Hanwoo and the owners' opinions. 20 menus using lean cut Hanwoo (rump or shank) were developed by $1^{st}$ and $2^{nd}$ cooking experiments, and in-depth interview of experts-groups. Of these, 12 menus suitable for the restaurant were finally selected based on the results of consumer's evaluation using JARS. Structured recipe flow diagram and recipe instructions were developed for future semi-processed or processing foods. Diverse recipe methods using lean cut Hanwoo were obtained from the study, however aggressive public relations work is required for promoting the developed menus.

• Asia-Pacific Journal of Business Venturing and Entrepreneurship
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• v.10 no.5
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• pp.63-71
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• 2015

Lean six sigma has to be utilized considering irrational system or defects based on features of organization beforehand. Otherwise, it won't improve anything but burden another heavy responsibilities to the people in charge. Therefore, a survey was conducted in addition to a literature review and a case study about lean six sigma to verify effective deployment method for lean 6sigma tools. The survey was conducted across for 96 interviewees who have MBB or BB was selected from 15 companies which have been running six sigma projects over 10 years and SPSS 16.0 was used for verifying reliability and validity of the research. In conclusion, some issues occurred in the process of six sigma projects were identified and effective deployment method of lean six sigma tools by integrating lean manufacturing into 6sigma were suggested based on those issues.

• Transactions of the Korean Society of Automotive Engineers
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• v.16 no.5
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• pp.179-189
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• 2008

The performance of Lean NOx Trap (LNT) based on the catalysts of Pt/K/Ba/$\gamma-Al_2O_3$ with proprietary washcoat formulation is studied using a bench flow reactor system. To investigate the effect of temperature and gas hourly space velocity (GHSV) on the nitrogen oxides (NOx) trapping capacity as well as NOx breakthrough time and final ratio of $NO_2$ to NO of LNT, series of adsorption isotherms are carried out with simulated exhaust gases of the lean burn engines. Since typical operation of LNT requires periodic regeneration with a short rich excursion, where the stored or trapped NOx is released and subsequently reduced to $N_2$, the effect of the duration of lean and rich phase and type of reductants on the NOx conversion is investigated. NOx storage capacity and breakthrough time obtained from adsorption isotherms shows a volcano-type dependence on the temperature with a maximum NOx storage capacity occurring $350^{\circ}C$ and with a maximum breakthrough time occurring $400^{\circ}C$ at all GHSVs investigated in this study. Also, maximum ratio of $NO_2$ to NO is obtained at $400^{\circ}C$ with a GHSV of $75,000\;hr^{-1}$ Lean/rich cycle of 100 s lean and 5 s rich used with a concentration of 1.33% of $H_2$ and 4% of CO in the rich phase is found to be optimum at operating temperature of $350^{\circ}C$ and a GHSV of $50,000\;hr^{-1}$.

• Journal of Animal Science and Technology
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• v.63 no.2
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• pp.332-338
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• 2021

The objective of this study was to predict body compositions of live pigs using bioelectrical impedance procedures. In experiment 1, 32 crossbred (Duroc × Landrace × Yorkshire) finishing pigs with an average weight at 84.06 kg were used. In experiment 2, 96 crossbred (Duroc × Landrace × Yorkshire) finishing pigs with an average weight at 88.8 kg were used. A four-terminal body composition analyser was utilized to determine fat percentage. Lean meat percentage and backfat thickness were measured with a lean meat measuring meter. In experiment 1, fat percentage was not significantly correlated with lean meat percentage, although a tendency (p < 0.1) of a negative correlation was found. Backfat thickness was significantly correlated with fat percentage and lean meat percentage (r = 0.745 and r = -0.961, respectively). Coefficients of determination for fat percentage with lean meat percentage, fat percentage with backfat thickness, and backfat thickness with lean meat percentage were 0.503, 0.566, and 0.923, respectively. In experiment 2, fat percentage was significantly correlated with lean meat percentage (r = -0.972). Backfat thickness was also significantly correlated with fat percentage and lean meat percentage (r = 0.935 and r = -0.957, respectively). Results of this study indicate that bioelectrical impedance analysis might be useful for predicting body compositions of live finishing pigs.

• International Journal of Automotive Technology
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• v.2 no.4
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• pp.147-155
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• 2001

Analysis of the thermodynamic cycle of IC engine from the point of view of economy and emissions was carried out. From this analysis potential capability of engine development was derived. This potential capability is lean-burn engine, fuelled with homogeneous mixture with $\lambda \geq$ 1.4. Several different modes of fuelling were proposed and tested on one-cylinder test engine from the point of view of extending lean operating limit of the engine, emissions and fuel economy. Among them were: fuelling with evaporated preheated gasoline, with gas (LPG evaporated) and with liquid butane. From these modes, fuelling with liquid butane injected to inlet port was selected and finally tested. This novel system of fuelling offered better than standard engine performances and emissions at lean operating limit. These results were validated on full-scale two-cylinder engine.