• Communications for Statistical Applications and Methods
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• v.18 no.6
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• pp.687-696
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• 2011

Customer Lifetime or Customer Lifetime Value is a essential metric of differentiated CRM marketing and differentiated marketing strategy as a company core competency. However, customer lifetime used in companies is easily obtained from a confined simple customer attrition rate at some specific time point regardless of customer characteristics. In this study, in order to overcome the constraints of previous simple methods and to make practical use of it in industries, we suggest a method that estimates a customer lifetime using a customer segment based survival analysis with the censored data of customers; in addition, we apply this method to A mobile telecom company data. A method using customer segment based survival analysis is suggested in this study 1) includes all customers having different subscription dates, 2) reduces individual error, 3) can reflect trends after the observed time point and is more realistic.

• Journal of Microbiology and Biotechnology
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• v.6 no.6
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• pp.432-438
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• 1996

Native crystalline chitin was hydrolyzed in an agitated bead reaction system using crude chitinase excreted from Aspergillus fumigatus JC-19. The reaction was enhanced significantly, and the concentration and yield of reducing sugar after 48 hours were measured to be 35.42 g/I (w/v) and 0.64, respectively, around 1.86 times higher than those of the conventional system that was carried out without glass beads. The effect of reaction conditions, such as the amounts of chitin, chitinase and glass beads, and the size of glass bead, were examined. Ball milled chitin was also hydrolyzed in the agitated bead reaction system, the conversion yield and reaction rate of ball milled chitin for 24 hours increased up to 0.87 and 48.02 g/I, respectively. Chitinase showed relatively high stability in the agitated bead reaction system, particularly in the presence of enzyme stabilizer, $Ca^{++}$, which played a critical role in preventing the deactivation of chitinase by the physical impact of glass beads. The variations of the structural features of chitin during the reaction were followed by SEM and X-ray diffraction, and the enhanced hydrolysis reaction was caused by both the fragmentation of chitin particles and the destruction of the crystalline structure owing to the synergic effects of the attrition of glass beads and the hydrolytic action of chitinase.

• Nutrition Research and Practice
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• v.13 no.5
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• pp.415-424
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• 2019

BACKGROUND/OBJECTIVES: Existing evidence on lifestyle modification programs for weight loss is limited by the high attrition rate of such programs. Identifying predictors of adherence to a lifestyle modification program could result in program improvement. However, little is known about behavior-specific adherence and its psychological predictors. This study aimed to examine the psychological predictors of adherence after one-month participation in a community-based lifestyle modification program among Chinese overweight and obese adults in Hong Kong. SUBJECTS/METHODS: A total of 205 Chinese overweight and obese adults aged $38.9{\pm}10.5years$ completed the study. Data were collected at baseline and after one month using self-reported questionnaires, which assessed knowledge (self-developed scale), motivation (Treatment Self-Regulation Questionnaire), stage of change (Stage of Exercise Scale) and self-efficacy (Self-Rated Abilities for Health Practices Scale). At one month, a 4-day dietary recall and the International Physical Activity Questionnaire-Short Form were used to assess dietary and physical activity (PA) adherence. Food and PA diaries were examined to indicate self-monitoring. Program attendance was tracked between baseline and one-month follow-up. RESULTS: After one month, participants reported high dietary adherence, attendance, and adherence to self-monitoring but low PA adherence. Multiple regression analyses suggested that diet self-efficacy (baseline) and nutrition knowledge (one-month change) were independent predictors of dietary adherence score at one month, whereas autonomous PA motivation (baseline) and PA self-efficacy (both baseline and one-month change) were independent predictors of PA adherence score at one month. No significant psychological predictor was identified for attendance or self-monitoring. CONCLUSIONS: The results suggest that the effect of psychological factors on adherence differs between diet and PA adherence outcomes. To promote adherence, practitioners should assess self-efficacy, knowledge, and motivation at the beginning of a weight-loss program and explore behavior-specific strategies to improve knowledge and self-efficacy. The results of this study have direct implications for program improvements.

• Journal of the Korean Society of Physical Medicine
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• v.18 no.4
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• pp.109-119
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• 2023

PURPOSE: The definition and scope of biofeedback are broad and lack a clear framework. Therefore, efforts are needed to clearly understand the exact range and definition of biofeedback based on the research and development conducted to date. Thus, the purpose of this study was to arrive at the definition and scope of biofeedback through a literature review and analysis of its application methods. METHODS: This study is a systematic literature review conducted to understand the various types and effects of biofeedback. International databases such as Google Scholar and PubMed were used. Domestic databases utilized for keyword searches included the Research Information Sharing Service (RISS) and the National Digital Science Library (NDSL). Quality assessment of the selected studies in the selection process was done using the Cochrane risk of bias, and the research was analyzed according to the population, intervention, control, and outcomes (PICO) format. RESULTS: Studies conducted between 2019 and 2021 were selected, with 4 papers falling under physiological classifications and 7 under biomechanical classifications. The quality assessment results showed that random sequence generation, allocation concealment, performance bias, and reporting bias were unclear. Detection bias was moderate, and attrition bias and other biases were low. Out of the 11 papers, 9 dealt with physical function outcomes, 5 with daily life activities, and 3 with mental functions. CONCLUSION: Physiological biofeedback tended to influence psychological factors more than physical functions, while biomechanical biofeedback tended to have a positive impact on physical functions.

• The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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• v.4 no.3
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• pp.226-236
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• 1999

Growth, reproduction, mortality, and production of Laminaria japonica were experimentally studied at a cultivation ground on the coast of llkwang, where the largest amount of cultivated Laminaria has been produced in Korea. For this experiment, young sporophytes (0.33 cm in mean length) grown in the laboratory were transplanted at the depth of 3 m and field surveys on them were conducted twice a month from December, 1995 to August, 1996. Plants exhibited an annual life span; they were completely dead by August. Frond width, thickness, and wet weight showed similar pattern of seasonal growth and reached their maxima in July, but frond length showed no more increment after May. Maximum mean frond length and weight were 199.8 cm and 333.0 g wet wt., respectively. Overall meristematic growth in length and weight were 384.0 cm and 393.6 g wet wt., respectively. Absolute growth rates (AGR) which were calculated from the length of tissue developed from meristem varied seasonally; AGR of length and weight reached maxima in March (3.6 $cm{\cdot}d^{-1}$) and May (3.8 g wet $wt{\cdot}d^{-1}$), respectively. Absolute attrition rates gradually increased from February to July. Seasonal differences in growth and attrition rates appeared to be related to seawater temperature and nitrogen concentration in seawater. Reproductive sporophytes bearing sprorangium sorus began to occur from April, and the ratio of sorus area to blade area reached its maximum in July (0.034). Survival rate was exponentially decreased; more than 90% of plants decayed within 56 days after outplanting. After February, mortality was size-specific; mortality of smaller plants less than 30 cm in length were relatively higher. Maximum biomass occured in July (285.6 kg wet $wt{\cdot}m^{-2}$) and annual production was 758.7 kg wet $wt{\cdot}m^{-2}$.

• The Journal of Korean Academy of Prosthodontics
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• v.52 no.4
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• pp.317-323
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• 2014

Dentinogenesis Imperfecta, with a high incidence rate of 1 : 6 - 8000, is inherited by autosomal dominant genetic transmission. This dental disorder causes discoloration of the teeth and the enamel and dentin show hypoplastic or hypocalcified defects which lead to frequent fractures and rapid attrition. Therefore, timely treatment is necessary for the preservation of the remaining teeth. In this particular case, a 19-year-old patient suffering from Type 1 dentinogenesis imperfecta showed signs of brownish hued teeth with multiple fractures, a loss of vertical dimension, excessive interdental space in the maxillary anterior teeth, and a lack of 5 posterior teeth. To improve the esthetic appearance of the anterior teeth, the vertical dimension was increased. Resin caps were used to alleviate the difficulty of taking an impression of multiple teeth at once. Monolithic zirconia materials used in this case showed high fracture strength and the ability to mask the discoloration of the teeth and therefore, functionally and esthetically favorable results were achieved.

• Journal of Music and Human Behavior
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• v.10 no.2
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• pp.1-33
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• 2013

The aim of this study was to systematically review the latest clinical trials in music medicine and medical music therapy for pediatric patients. Thirteen databases were searched to obtain randomized controlled/crossover design studies published between the year 2000 and 2012 in English language. Out of 1012 articles retrieved in the initial search, fifteen studies were identified based on an exclusion criteria. Overall, selected articles involved children 1 month to 18 years, sample size of 11 to 150, and total participants of 987. Studies were classified and compared as music medicine or music therapy studies through a systematic synthesis assessing general characteristics, methodological quality, measured outcomes, types of interventions and the study results. Seven music medicine and eight music therapy studies measured seven dependent variables using thirty-six different measurement tools with a large heterogeneity in the selection, type, and method of music interventions. Evaluation of the methodological quality revealed that many studies did not provide a full report of the research method, and did not meet some or most methodological standards, such as randomization, allocation concealment, double or partial blinding, and intention to treat analysis. Although overall research results were positive if not significant, poor methodological quality and heterogeneity in design and intervention strategies raise the question of research bias and trustworthiness issues. The systematic review concluded that music may have a valuable clinical effect in addressing the physical and psychosocial needs of hospitalized children, although more rigorous, homogeneous and replicable studies are greatly needed.

• Journal of Korean Academic Society of Home Health Care Nursing
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• v.2
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• pp.5-18
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• 1995

While the socioeonomic status of Koreas has been dramatically increasing in recent years, chronic and geriatric diseases have also been on the rise, bringing about many changes in our health care system. The basic goals of the home health care are to reduce health care costs, to increase the attrition rate in general hospitals, and to care for patients effectively and conveniontly at home. The purpose of this paper is to review and examine the current status of the home health care in Korea throughout the reports, surveys, other informations and education system of home health nurse. We identified the various types of home health care services programs, such as hospital-based home health care operated in public sector(demonstration project) and community-based home health care in health centers or in private sector, that is, Korean Nurse Association. Hospital based home heatlh care model was established as an alternative to traditional in-patiet services. Quality assurance and client satisfaction is an important measure of care received and establishment of payment and reimbursement for home health care services is important in promotng the home health care. We found out a fee-per-visit system composed of three kinds of fees : a basic service fee(16,000 Won), a travel fee(5,000 Won), and per-service fees (variables). Like fees paid for in-patient care, insureds pay 20% and insurers pay 80% of the basic and per-service fee. The travel fee is borne totally by the insured. Home health care continues to be viewed as not only the most preferred way to provide care to clients, but also the most cost effective. Home health care is that component of a continuum of comprehensive health care whereby health services are provided to individuals and families in their places of residence for the purpose of promoting, maintaining, or restoring health, or of maximizing the level of independence, while minimizing illness. Services appropriate to the needs of the individual patient and family should be planned and provided, nursing is to be a force for positive change and enhanced the nursing professionalism. Whatever type of involvement of home health care, it is essential to remember that home health care is highly service-oriented and highly touch health car deilvery system.

• Journal of Dental Rehabilitation and Applied Science
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• v.28 no.1
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• pp.87-101
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• 2012

Bruxism is extensively defined as a diurnal or nocturnal parafunctional habit of tooth clenching or grinding. The etiology of bruxism may be categorized as central factors or peripheral factors and according to previous research results, central factors are assumed to be the main cause. Bruxism may cause tooth attrition, cervical abfraction, masseter hypertrophy, masseter or temporalis muscle pain, temporomandibular joint arthralgia, trismus, tooth or restoration fracture, pulpitis, trauma from occlusion and clenching in particularly may cause linea alba, buccal mucosa or tongue ridging. An oral appliance, electromyogram or polysomnogram is used as a tool for diagnosis and the American Sleep Disorders Association has proposed a clinical criteria. However the exact etiology of bruxism is yet controversial and the selection of treatment should be done with caution. When the rate of bruxism is moderate or greater and is accompanied with clinical symptoms and signs, treatment such as control of dangerous factors, use of an oral appliance, botulinum toxin injection, pharmacologic therapy and biofeedback therapy may be considered. So far, oral appliance treatment is known to be the most rational choice for bruxism treatment. For patients in need of esthetic correction of hypertrophic masseters, as well as bruxism treatment, botulinum toxin injection may be a choice.

• Journal of Chest Surgery
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• v.38 no.3 s.248
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• pp.191-196
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• 2005

We analysed the characteristics of anastomotic sites after coronary artery bypass grafting (CABG) using coronary angiographies (CAGs) performed at one and five years postoperatively in the same patient population. Material and Method: Among the 219 patients who underwent isolated CABGs between January 1995 and December 1997, follow-up coronary angiograms were performed in 149 ($75.3\%$) patients at one year and in 115 ($58.1\%$) patients at five years postoperatively. FitzGibbon grading system was used to evaluate the anastomotic sites. Result: The patency rates of arterial grafts at one- and five-year were $96.5\%$ (192/199) and $93.1\%$ (134/144), which were higher than those of saphenous vein grafts (SVGs) ($82.9\%$ (224/270) and $77.5\%$ (141/182), respectively) (p=0.01). Although there were significant decreases in the patency rates between one- and five-year CAGs of both arterial and venous grafts, the proportion of FitzGibbon grade B among the SVGs was increased from $5.2\%$ (one-year) to $8.2\%$ (five-year), suggesting the progression of vein graft disease (p < 0.01). Conclusion: The patency rate of the arterial graft was higher than that of SVG in both one- and five-year CAGs. The attrition rate of saphenous vein graft was higher than arterial grafts.