• Journal of Microbiology and Biotechnology
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• v.32 no.2
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• pp.195-204
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• 2022

Chinese chive (Allium tuberosum Rottler) has potential risks associated with pathogenic bacterial contamination as it is usually consumed raw. In this study, we investigated the microbiota of Chinese chives purchased from traditional markets and grocery stores in March (Spring) and June (Summer) 2017. Differences in bacterial diversity were observed, and the microbial composition varied across sampling times and sites. In June, potential pathogenic genera, such as Escherichia, Enterobacter, and Pantoea, accounted for a high proportion of the microbiota in samples purchased from the traditional market. A large number of pathogenic bacteria (Acinetobacter lwoffii, Bacillus cereus, Klebsiella pneumoniae, and Serratia marcescens) were detected in the June samples at a relatively high rate. In addition, the influence of the washing treatment on Chinese chive microbiota was analyzed. After storage at 26℃, the washing treatment accelerated the growth of enterohemorrhagic Escherichia coli (EHEC) because it caused dynamic shifts in Chinese chive indigenous microbiota. These results expand our knowledge of the microbiota in Chinese chives and provide data for the prediction and prevention of food-borne illnesses.

• Journal of Intelligence and Information Systems
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• v.9 no.3
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• pp.23-47
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• 2003

Traditional studies for customer relationship management (CRM) generally focus on static CRM in a specific time frame. The static CRM and customer behavior knowledge derived could help marketers to redirect marketing resources fur profit gain at that given point in time. However, as time goes, the static knowledge becomes obsolete. Therefore, application of CRM to an online retailer should be done dynamically in time. Customer-based analysis should observe the past purchase behavior of customers to understand their current and likely future purchase patterns in consumer markets, and to divide a market into distinct subsets of customers, any of which may conceivably be selected as a market target to be reached with a distinct marketing mix. Though the concept of buying-behavior-based CRM was advanced several decades ago, virtually little application of the dynamic CRM has been reported to date. In this paper, we propose a dynamic CRM model utilizing data mining and a Monitoring Agent System (MAS) to extract longitudinal knowledge from the customer data and to analyze customer behavior patterns over time for the Internet retailer. The proposed model includes an extensive analysis about a customer career path that observes behaviors of segment shifts of each customer: prediction of customer careers, identification of dominant career paths that most customers show and their managerial implications, and about the evolution of customer segments over time. furthermore, we show that dynamic CRM could be useful for solving several managerial problems which any retailers may face.

• Journal of Distribution Science
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• v.14 no.1
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• pp.93-102
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• 2016

Purpose - The purpose of paper is studying the static and dynamic side for long-term memory storage properties, and increase the explanatory power regarding the long-term memory process by looking at the long-term storage attributes, Korea Composite Stock Price Index. The reason for the use of GPH statistic is to derive the modified statistic Korea's stock market, and to research a process of long-term memory. Research design, data, and methodology - Level shifts were subjected to be an empirical analysis by applying the GPH method. It has been modified by taking into account the daily log return of the Korea Composite Stock Price Index a. The Data, used for the stock market to analyze whether deciding the action by the long-term memory process, yield daily stock price index of the Korea Composite Stock Price Index and the rate of return a log. The studies were proceeded with long-term memory and long-term semiparametric method in deriving the long-term memory estimators. Chapter 2 examines the leading research, and Chapter 3 describes the long-term memory processes and estimation methods. GPH statistics induced modifications of statistics and discussed Whittle statistic. Chapter 4 used Korea Composite Stock Price Index to estimate the long-term memory process parameters. Chapter 6 presents the conclusions and implications. Results - If the price of the time series is generated by the abnormal process, it may be located in long-term memory by a time series. However, test results by price fixed GPH method is not followed by long-term memory process or fractional differential process. In the case of the time-series level shift, the present test method for a long-term memory processes has a considerable amount of bias, and there exists a structural change in the stock distribution market. This structural change has implications in level shift. Stratum level shift assays are not considered as shifted strata. They exist distinctly in the stock secondary market as bias, and are presented in the test statistic of non-long-term memory process. It also generates an error as a long-term memory that could lead to false results. Conclusions - Changes in long-term memory characteristics associated with level shift present the following two suggestions. One, if any impact outside is flowed for a long period of time, we can know that the long-term memory processes have characteristic of the average return gradually. When the investor makes an investment, the same reasoning applies to him in the light of the characteristics of the long-term memory. It is suggested that when investors make decisions on investment, it is necessary to consider the characters of the long-term storage in reference with causing investors to increase the uncertainty and potential. The other one is the thing which must be considered variously according to time-series. The research for price-earnings ratio and investment risk should be composed of the long-term memory characters, and it would have more predictability.

• Journal of the Korean association of regional geographers
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• v.13 no.6
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• pp.623-638
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• 2007

This paper debates on two different theoretical positions in explaining corporate adaptation. Until the 1980s, a restructuring perspective had dominated in explaining corporate success and adaptation. However, this perspective pays little attention to how firms adapt to environmental change and why some firms adapt successfully, while some others fail to adapt. Thus a restructuring perspective does not give insights into a context-specific explanation of corporate learning and adaptation. More recently, especially since the 1990s, academic focus on corporate adaptation and evolution has shifted towards exploring the nature of learning that leads to the dynamic competitiveness. A learning perspective emphasizes the influence of knowledge, learning and competence on corporate evolution. However, it reveals that this view is also less appropriate for explaining corporate adaptation in radical shifts in environment. In this context, the evolutionary theories of the firm need to seek to maintain a balance between two theoretical positions in order to understand more effectively the dynamic evolution and adaptation of the firm. This paper shows that the dynamics of corporate adaptation and evolution are an outcome of the mixture of perpetual processes of restructuring and learning, both continuous and discontinuous.

• Land and Housing Review
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• v.14 no.4
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• pp.47-62
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• 2023

Using the dynamic panel model, this study investigates rent determinants for small and medium-sized office buildings in Korea's CBD and Gangnam areas, key business districts. The results reveal that rents for small and medium-sized office buildings in CBD and Gangnam areas are influenced by macroeconomic fluctuations and characteristics of buildings and locations, suggesting a market with both spatial consumer and investment goods attributes. There are several investment implications as follows. First, even if the location in the CBD area is advantageous, the practical limitations in renovating aging small and medium-sized office buildings must be taken into account when investing. Second, parking conditions are a key factor influencing rent prices in CBD areas, so evaluating the parking facilities and improvement potential of small and medium-sized office buildings is essential for investors. Finally, due to the high sensitivity of Gangnam's small and medium-sized office market to macroeconomic trends, it's vital to prioritize monetary policy shifts as a key factor in investment decisions.

• Korean Journal of Applied Biomechanics
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• v.12 no.1
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• pp.205-219
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• 2002

This research seeks to identify the plantar pressure distribution graph and change in force in connection with effective golf drive strokes and thus to help ordinary golfers have appropriate understanding on the moving of the center of weight and learn desirable drive swing movements. To this end, we conducted surveys on five excellent golfers to analyze the plantar pressure applied when performing golf drive strokes, and suggested dynamic variables quantitatively. 1) Our research presents the desire movements as follows. For the time change in connection with the whole movement, as a golfer raises the club head horizontally low above ground from the address to the top swing, he makes a semicircle using the left elbow joint and shaft and slowly turns his body, thus lengthening the time. And, as the golfer twists the right waist from the middle swing to the impact with the head taking address movement, and does a quick movement, thus shortening the time. 2) For the change in pressure distribution by phase, to strike a strong shot with his weight imposed from the middle swing to the impact, a golfer uses centrifugal force, fixes his left foot, and makes impact. This showed greater pressure distribution on the left sole than on the right sole. 3) For the force distribution graph by phase, the force in the sole from the address to halfway swing movements is distributed to the left foot with 46% and to the right foot with 54%. And, with the starting of down swing, as the weight shifts to the left foot, the force is distributed to the left sole with 58%. Thus, during the impact and follow through movements, it is desirable for a golfer to allow his left foot to take the weight with the right foot balancing the body. 4) The maximum pressure distribution and average of the maximum force in connection with the whole movement changed as the left (foot) and right (foot) supported opposing force, and the maximum pressure distribution also showed much greater on the left sole.

• Wind and Structures
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• v.20 no.3
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• pp.449-468
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• 2015

Current wind-resistance designs of large-scale indirect dry cooling towers (IDCTs) exclude an important factor: the influence of the ventilation rate for radiator shutter on wind loads on the outer surfaces of the tower shell. More seemingly overlooked aspects are the effects of various ventilation rates on the wind pressure distribution on the tower surfaces of two IDCTs, and the feature of the flow field around them. In order to investigate the effects of the radiator shutter ventilation rates on the aerodynamic interference between IDCTs, this paper established the numerical wind tunnel model based on the Computational Fluid Dynamic (CFD) technology, and analyzed the influences of various radiator shutter ventilation rates on the aerodynamic loads acting upon a single and two extra-large IDCTs during building, installation, and operation stages. Through the comparison with the results of physical wind tunnel test and different design codes, the results indicated that: the influence of the ventilation rate on the flow field and shape coefficients on the outer surface of a single IDCT is weak, and the curve of mean shape coefficients is close to the reference curve provided by the current design code. In a two-tower combination, the ventilation rate significantly affects the downwind surface of the front tower and the upwind surface of the back tower, and the larger positive pressure shifts down along the upwind surface of the back tower as the ventilation rate increases. The ventilation rate significantly influences the drag force coefficient of the back tower in a two-tower combination, the drag force coefficient increases with the ventilation rate and reaches the maximum in a building status of full ventilation, and the maximum drag coefficient is 11% greater than that with complete closure.

• Journal of Korean Neurosurgical Society
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• v.50 no.4
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• pp.377-380
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• 2011

Objective : The purpose of this study was to determine the anatomic relationships between neurovascular structures and the transverse carpal ligament so as to avoid complications during endoscopic carpal tunnel surgery. Methods : Twenty-eight patients (age range, 35-69 years) with carpal tunnel syndrome were entered into the study. We examined through wrist magnetic resonance imaging in three different positions (neutral, radial flexion, and ulnar flexion) and determined several anatomic landmark (distance from the hamate hook to the median nerve, ulnar nerve, and ulnar vessel) based on the lateral margin of the hook of the hamate. The median nerve and ulnar neurovascular structure were studied with the wrist in the neutral, ulnar, and radial flexion positions. Results : The ulnar neurovascular structures usually passed just over or ulnar to the hook of the hamate. However, in 12 hands, a looped ulnar artery coursed 0.6-3.3 mm radial to the hook of the hamate and continued to the superficial palmar arch. The looped ulnar artery migrates on the ulnar side of Guyon's canal (-5.2-1.8 mm radial to the hook of the hamate) with the wrist in radial flexion. During ulnar flexion of the wrist, the ulnar artery shifts more radially beyond the hook of the hamate (-2.5-5.7 mm). Conclusion : It is appropriate to transect the ligament greater than 4 mm apart from the lateral margin of the hook of the hamate without placing the edge of the scalpel toward the ulnar side. We would also recommend not transecting the transverse carpal ligament in the ulnar flexed wrist position to protect the ulnar neurovascular structure.

• Korean Institute of Interior Design Journal
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• v.13 no.5
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• pp.181-189
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• 2004

This study consists of two parts, in which the traditional discourses about light and color are analysed hermeneutically, The first part deals with the optical and chromatic discourse that stands in the same context with the aesthetic, and the second with the analysis of color phenomenon that is constituitive of space. From the ancient time the basic parameters of the conceptual thinking such as the virtual, simulacrum, have sticked to the inevitable status, which mediates to represent the original that can never present by oneself. In modern times this specificity of the virtual could have been connected with the problem, how and by which means objects can be perceived and grasped in itself. Among the barometers to the problem ‘color’ or ‘color perception’ has been regarded as the distinct one, in which the relationship between the image and the identifying of this one, the relationship between the perceived image and the perceiving subject and the problem of the spatiality of color and surface can be dwelled on. Through the explication of the chromatic and aesthetic discourse it can be recognized that color, surface and space are interacted with one another. Colors on the surface are not only the dynamic interpoints between the memory and the forgetfulness, but also the virtual interfaces, in which the spatialising actions happen incessantly. At this point it can be illuminated that the space-constituitive dimension of color is correlative with the dimension of chromatic effects of spatialising. Therefore color as well as surface as the spatial happening must be apprehended as the one, which constitutes the spatialising and at the same time varies and shifts itself into another on the purpose of the other spatialising.

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.34 no.6
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• pp.83-91
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• 2006

An advanced method of Relaxed Static Stability (RSS) is utilized for improving the aerodynamic performance of modern version supersonic jet fighter aircraft. The flight control system utilizes RSS criteria in longitudinal axis to achieve performance enhancements and improve stability. The flight control law of T-50 advanced trainer employs RSS concept in order to improve the aerodynamic performance and guarantee aircraft stability. The longitudinal center of gravity(X-c.g) varies as a function of external stores, fuel state and gear position. Shifts in X-c.g relate directly to longitudinal static margin in aircraft stability. This paper deals the maximum aft X-c.g for critical aircraft loadings and checks static margin limits using sensitivity such as damping, natural frequency, gain and phase margin. And nonlinear analysis was conducted for such as short period input. And also, this paper shows the T-50 aircraft stability based on the result of high angle of attack flight such as upright and inverted departure.