• 품질경영학회지
• /
• 제38권1호
• /
• pp.10-19
• /
• 2010

The competitive strategies of the Korean manufacturing companies have changed from the "cost leadership" strategy in the early developing stage since 1960's to the "stuck in the middle" position since 1990's in the face of emerging new cost leaders as the Chinese companies. The data on the strategic contents of the Korean manufacturing companies show that their strategies are seeking the value innovation through not only quality improvement but also cost reduction altogether rather than selecting one on the trade-off relation between the both competitive dimensions. Their strategic actions seem to be seeking the operational efficiencies through all the value chain activities rather than the strategic effectiveness by selecting and focusing on the specific competitive dimension, which is considered as a typical strategic approach. Their strategy seems to be non-strategic in the general sense. But their non-strategically looking behaviors can be reasonable enough for their sandwiched competitive position between the global quality leaders and following cost leaders. This paper explains why their strategies can be right through the theoretical explanations by using the quality-price elasticity approaches for the consumer behaviors. We can call their strategic activities as the value innovation strategy.

• 응용통계연구
• /
• 제28권3호
• /
• pp.385-392
• /
• 2015

주성분분석은 차원축소를 위한 대표적 기법이다. 주성분분석에서 변수들이 측정단위가 다르거나 분산의 불균형이 심할 경우 흔히 변수를 표준화한 다음 분석할 것이 권장된다. 표준화 변환은 표준편차를 나누어주는 변환인데, 측정단위에 무관하게 만들기 위해서라면 평균을 나누어주는 변환도 고려해볼 수 있다. 표준화 변환을 한 다음 주성분분석하는 것은 상관행렬로 주성분분석하는 것과 같은데, 평균을 나누어주는 변환을 한 후 주성분분석하는 것은 변동계수와 관련된 행렬로 주성분분석하는 것과 같음을 보이고, 그렇게 변환을 한 다음 주성분분석을 실시하는 것이 왜 필요한가를 설명하였다.

• Journal of Periodontal and Implant Science
• /
• 제41권1호
• /
• pp.44-50
• /
• 2011

Purpose: Pathologic tooth migration (PTM) is a tooth displacement which is derived from imbalance of tooth retention force and is dominantly found out in maxillary anterior area. PTM in maxillary anterior area was tried to corrected with periodontal treatment and a clear aligner in this study and the result was evaluated clinically and radiographically. Methods: For the treatment of a patient with chronic periodontal disease accompanied by maxillary anterior pathologic tooth migration, clear aligner was applied to move teeth after a series of case-related periodontal therapy. Clinically, probing depth, gingival recession, clinical attachment level and mobility were measured pre- and post-treatment, and radiographic examination was performed as well. Results: Clinically, we found the decrease of the probing depth, gingival recession, clinical attachment level and mobility. And we could also acknowledge the reduction of vertical and horizontal dimension on infrabony defect radiographically. However, it is still controversial if there was an actual bone filling. Conclusions: Clear aligner is an effective appliance to move teeth since it costs little in terms of expense and time. In addition, it wraps whole crowns, providing advantages to deal with crowding, spacing, and size of arch. In short, clear aligner could be a useful treatment option for PTM patient, since it provides decreased probing depth, gingival recession, clinical attachment level, mobility and esthetical restoration.

• 한국정밀공학회지
• /
• 제15권12호
• /
• pp.142-147
• /
• 1998

Developing robot hands with multi-degree-of-freedom is one of the topics that researchers have recently begun to improve the limitation by adding flexibility and dexterity. In this study, an articulated servo-pneumatic robot hand system with direct-drive joints has been developed whose main feature is the minimization of the dimension. The servo-pneumatic system is advantageous to fabricate a dexterous robot hand system due to the high torque-to-weight and torque-to-volume ratio. This enables the design of a finger joint with an integrated rotary vane type actuator which produces high output torque without reduction gears, being very robust. In order to control the servo-pneumatic finger joints, a miniature proportional valve that can be attached to the robot hand is required. In this paper, a flapper nozzle type 4/3-way proportional directional valve has been designed and tested. The experimental results show that the developed valve can control a finger joint satisfactorily without much vibratory joint movements and acoustic noises.

• 한국정밀공학회지
• /
• 제31권10호
• /
• pp.865-871
• /
• 2014

Paradigm shift to 3-D chip stacking in electronic packaging has induced a lot of integration challenges due to the reduction in wafer thickness and pitch size. This study presents a hybrid bonding technology by self-alignment effect in order to improve the flip chip bonding accuracy with ultra-thin wafer. Optimization of Cu pillar bump formation and evaluation of various factors on self-alignment effect was performed. As a result, highly-improved bonding accuracy of thin wafer with a $50{\mu}m$ of thickness was achieved without solder bridging or bump misalignment by applying reflow process after thermo-compression bonding process. Reflow process caused the inherently-misaligned micro-bump to be aligned due to the interface tension between Si die and solder bump. Control of solder bump volume with respect to the chip dimension was the critical factor for self-alignment effect. This study indicated that bump design for 3D packaging could be tuned for the improvement of micro-bonding quality.

• Journal of Electrical Engineering and Technology
• /
• 제10권4호
• /
• pp.1886-1898
• /
• 2015

In today’s era of advanced technological developments, the threats to the authenticity and integrity of digital images, in a nutshell, the threats to the Image Forensics Research communities have also increased proportionately. This happened as even for the ‘non-expert’ forgers, the availability of image processing tools has become a cakewalk. This image forgery poses a great problem for judicial authorities in any context of trade and commerce. Block matching based image cloning detection system is widely researched over the last 2-3 decades but this was discouraged by higher computational complexity and more time requirement at the algorithm level. Thus, for reducing time need, various dimension reduction techniques have been employed. Since a single technique cannot cope up with all the transformations like addition of noise, blurring, intensity variation, etc. we employ multiple techniques to a single image. In this paper, we have used Fuzzy logic approach for decision making and getting a global response of all the techniques, since their individual outputs depend on various parameters. Experimental results have given enthusiastic elicitations as regards various transformations to the digital image. Hence this paper proposes Fuzzy based cloning detection and classification system. Experimental results have shown that our detection system achieves classification accuracy of 94.12%. Detection accuracy (DAR) while in case of 81×81 sized copied portion the maximum accuracy achieved is 99.17% as regards subjection to transformations like Blurring, Intensity Variation and Gaussian Noise Addition.

• 대한기계학회논문집A
• /
• 제33권9호
• /
• pp.903-912
• /
• 2009

This study is focused on simulation-based dimensional tolerance optimization process (DTOP) to minimize vehicle pulls by reduction of dimensional variation in front suspension system. In previous studies, the effect of tires and wheel alignment sensitivity have mainly been investigated to eliminate vehicle pulls in nominal design condition without allocating optimal tolerance level for selected components, among various factors regarding vehicle pulls such as vehicle design parameters, vehicle weight balance, tires, and environmental factors. Unfortunately, there are wide variations in the real vehicle, and these have impacted actual vehicle pulls, especially wheel alignment effects from suspension geometry variation has not been considered in the previous studies. In the tolerance design of suspension, tolerance variables with the uncertainty such as parts dimensional variation, assembly process, datum position and direction, and assembly tool tolerance has a great influence on the variation of the suspension dimensional performances. This study introduces total vehicle pull prediction model in considering major key factors for vehicle pull sensitivity. The Monte Carlo-based tolerance analysis model using Taguchi robust method is developed to optimize dimensional tolerance parameters, satisfying on the target variation level.

• Structural Engineering and Mechanics
• /
• 제49권4호
• /
• pp.479-489
• /
• 2014

In the present study a parametric analysis is conducted to study the effect of pile dimension and soil properties on the nonlinear dynamic response of pile subjected to lateral sinusoidal load at the pile head. The study is conducted on soil-pile model of different pile diameter, pile length and soil modulus, and results are compared to get the effect. The soil-pile system is modelled using Finite element method. The programming is done in MATLAB. Time history analysis of model is done for varying non-dimensional frequency of load and the results are compared to get the non-dimensional frequency at which pile head displacement is maximum in each case. Maximum possible bending moment and soil-pile interacting forces for the dynamic excitation of the pile is also compared. When results are compared with the linear response, it is observed that non-dimensional frequency is reduced in nonlinear response on account of reduction in the soil stiffness due to yielding. Nonlinear response curve shows high amplitude as compared to linear response curve.

• 농촌계획
• /
• 제5권2호
• /
• pp.56-65
• /
• 1999

Recently, new concept and paradigm of 'Environmentally-Friendliness' is taking a growing interest in environmental planning and design. This study is to establish the evaluation model for environmentally-friendliness of 'Tourism Farms' in rural areas by LISREL structural equation model. A questionnaire survey was conducted for deputy manager group and expert group. As the Result of LISREL structural equation model, the environmentally-friendliness of tourism farms is composed of three categories. First, conservation of global environment (Low Impact), second, friendliness to surrounding nature(High Contact), and third, environmental health and amenities (Health & Amenity). Five indicators, such as (1)saving of energy and water resource, (2)reduction and reuse of garbage, (3)natural purification of sewage disposal, (4)utilization of natural energy, (5)campaign and education programs of environmentally-friendliness, were affecting the first category, i.e., conservation of global environment(Low Impact). Friendliness to surrounding nature (High Contact) is affected by 3 indicators, (1)contact to nature and diverse green areas, (2)water intimate & contact areas, (3)natural ecology observation by biotope. Finally, the dimension of environmental health and amenity is affected by 3 indicators, (1)nature affinity by farming experience, (2)environmental-friendliness of soil & crops by organic farming, (3) campaign and education programs of environmentally-friendliness. Total coefficient of determination of the structural equation model by LISREL was 0.897, which showed high explanatory power.

• 응용통계연구
• /
• 제22권6호
• /
• pp.1265-1275
• /
• 2009

본 논문에서는 반복인자가 여러 개인 반복측정자료에 대하여 반복인자간의 상관성을 고려한 복합공분산(composite covariance) 모형을 살펴보았다. 그러나 반복인자가 3개 이상인 경우에는 기존의 통계프로그램을 이용하여 적합하는 것이 불가능하다. 복합공분산 모형을 실제 자료에 적합하기위해 반복인자의 차원을 축소한 모형과 랜덤효과 모형을 이용하여 근사적으로 적합하는 방법을 제시하고 883명으로부터 수집한 반복인자가 3개인 혈압자료에 적용하였다.