• Communications for Statistical Applications and Methods
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• v.16 no.2
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• pp.265-275
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• 2009

This paper considers a linear regression model with a spatial autoregressive disturbance with ill-posed data and proposes the generalized maximum entropy(GME) estimator of regression coefficients. The performance of this estimator is investigated via Monte Carlo experiments. The results show that the GME estimator provides efficient and robust estimate for the unknown parameter.

• The Journal of Internal Korean Medicine
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• v.25 no.4
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• pp.221-226
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• 2004

Objective : This study was designed to evaluate the effects of oriental medicine therapy on a normal pressure hydrocephalus patient Methods : The clinical data was analyzed on a patient with normal pressure hydrocephalus whose main symptoms were gait apraxia, dementia and urinary incontinence, The patient was admitted to the internal medicine department of KyungWon university In-cheon Oriental Medical Hospital, on April 19, 2004 and remained until Apri 30, 2004. He was treated with herbal medicine(Oryung-San), acupuncture and moxa therapy. Results : After treatment, improvement was seen in gait apraxia, dementia and urinary disturbance. Conclusion : The study suggests that oriental medicine therapy is significantly effective in the treatment of normal pressure hydrocephalus.

• Journal of the Korean Society of Industry Convergence
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• v.8 no.2
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• pp.97-104
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• 2005

Usually, propagation attenuation of millimeter wave occurs by rainfall, snowfall, temperature, effect of pressure of air. In 60GHz wave band wireless communication network, temperature change becomes big factor of propagation loss department. Also, temperature change causes disturbance of 60GHz frequency at transceiver. In this study, we used 60GHz transceiver and found propagation loss of wireless path and operating frequency disturbance characteristics. In transceiver that there is no temperature compensated device, operating frequency of TX changed by 60.865GHz at temperature of $-5^{\circ}C$, and appeared by 60.730GHz when is $50^{\circ}C$. Therefore, operating frequency change width by temperature change are about 100MHz, greatly. But, in transceiver that there is temperature compensated device, operating frequency of TX changed by 60.830GHz at temperature of $-5^{\circ}C$, and appeared by 60.710GHz when is $50^{\circ}C$. Therefore, operating frequency change width by temperature change are about 20MHz. According to these result, we constructed between buildings examination wireless site for point to point wireless communication using 60GHz band transceivers who have do temperature compensated device, and investigated data transmission characteristics about ambient temperature change. Therefore, if use transceiver that have temperature compensated device, may overcome the wireless transmission error in 60GHz band wireless communication LAN networks despite of ambient temperature change.

• Nuclear Engineering and Technology
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• v.32 no.3
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• pp.261-273
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• 2000

During an extensive review made as part of the Integrated Diagnosis System project of the Maiden Reactor Project, MOAS (Maryland Operator Advisory System) was identified as one of the most thorough systems developed thus far. MOAS is an integrated on-line diagnosis system that encompasses diverse functional aspects that are required for an effective process disturbance management: (1) intelligent process monitoring and alarming, (2) on-line sensor data validation and sensor failure diagnosis, (3) on-line hardware (besides sensors) failure diagnosis, and (4) real-time corrective measure synthesis. The MOAS methodology was used at the Maiden Man-Machine Laboratory HAMMLAB of the OECD Maiden Reactor Project. The performance of MOAS, developed in G2 real-time expert system shell for the high-pressure preheaters of the NORS process in the HAMMLAB, was tested against a variety of transient scenarios, including failures of the control valves and sensors, and tube leakage of the preheaters. These tests showed that MOAS successfully carried out its intended functions, i.e., quickly recognizing an occurring disturbance, correctly diagnosing its cause, and presenting advice on its control to the operator. The lessons learned and insights gained during the implementation and performance tests also are discussed.

• International Journal of Naval Architecture and Ocean Engineering
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• v.7 no.1
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• pp.70-86
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• 2015

Short crested waves play an important role for planning and design of harbours. In this context a numerical simulation is carried out to evaluate wave tranquility inside a real harbour located in east coast of India. The annual offshore wave climate proximity to harbour site is established using Wave Model (WAM) hindcast wave data. The deep water waves are transformed to harbour front using a Near Shore spectral Wave model (NSW). A directional analysis is carried out to determine the probable incident wave directions towards the harbour. Most critical threshold wave height and wave period is chosen for normal operating conditions using exceedence probability analysis. Irregular random waves from various directions are generated confirming to Pierson Moskowitz spectrum at 20m water depth. Wave incident into inner harbor through harbor entrance is performed using Boussinesq Wave model (BW). Wave disturbance experienced inside the harbour and at various berths are analysed. The paper discusses the progresses took place in short wave modeling and it demonstrates application of wave climate for the evaluation of harbor tranquility using various types of wave models.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.20 no.3
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• pp.1106-1113
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• 1996

The phase criterion of the feedback cycle of low-speed edgetones has been obtained using the jet-edge interaction model which is based on the substitution of an array of dipoles for the reaction of the wedge to the impinging jet. The edgetone is produced by the feedback loop between the downstream-convected sinuous disturbance and upstream-propagating waves generated by the impingement of the disturbance on the wedge. By estimation of the phase difference between the downstream and the upstream disturbances, the relationship between the edge distance and the wavelength is obtained according to the phase-locking condition at the nozzle lip. With a little variation depending on the characteristics of jet-edge interaction, the criterion can be approximated as follows: h/.LAMBDA. + h/.lambda. = n - 1/4, where h is the stand-off distance between the nozzle lip and the edge tip, .LAMBDA. is the wavelength of downstream-convected wave, .lambda. is the wavelength of the upstream-propagating acoustic wave and n is the stage number for the ladder-like characteristics of frequency. The present criterion has been confirmed by estimating wavelengths from available experimental data and investigating their appropriateness. The above criterion has been found to be effective up to 90.deg. of wedge angle corresponding to the cavitytones.

• Sleep Medicine and Psychophysiology
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• v.9 no.2
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• pp.96-99
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• 2002

Menopause, the cessation of menstruation caused by the decline in estrogen production, occurs in 95% of women between 40 and 60 years. Sleep disturbance is a frequent complaint during the perimenopause period. In contrast to premenopausla women, menopausal women experience more reduction in the total sleep hours and report more sleep disturbances, such as insomnia, noctiria and sleep disordered breathing. But the prevalence, etiology and treatment of sleep disturbances in menopause are still controversal. So further investigations are required to elucidate the factors that account for the differences in sleep disturbance between premenopausal and postmenopausal women. There are suggestive data that estrogen and progesterone deficiency may increase the susceptibility for sleep disorder in menopause. Furthermore, there are suggestive evidence from observational studies and a limited number of randomized, controlled trials that hormone replacement therapy after menopause improves sleep. However, the clinical relevance of hormone replacement therapy is unproved. So the overall benefit of hormonal replacement in postmenopausal women with sleep related disorders should be individualized to avoid potential side effects. Several studies evaluated the role of melatonin, because this hormone has effects on core body temperature & insomnia. But the exact dosage and the effects of long-term use of melatonin are unclear. So, caution is indicated in melatonin administration.

• Journal of Korean Biological Nursing Science
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• v.19 no.4
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• pp.252-257
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• 2017

Purpose: This study aimed to investigate the associations of sleep, dietary behaviors and physical activity with quality of life among shift-work nurses. Methods: For this cross-sectional descriptive study, data were collected from 191 shift-work nurses in a tertiary hospital. Multiple linear regression analysis was used to identify the relationships among variables. Results: The levels of sleep quality, dietary behaviors and physical activity were low. Factors associated with quality of life among shift-work nurses included sleep disturbance (B=-0.16, ${\beta}=-0.26$, p<.001), dietary behaviors (B=0.28, ${\beta}=0.24$, p<.001), and physical activity (B=0.05, ${\beta}=0.19$, p<.001). The strongest factor was sleep disturbance. Conclusion: In order to improve quality of life among shift-work nurses, it is significant to encourage and maintain health behaviors such as sleep, dietary behaviors and physical activity. Under the circumstances where shift-work cannot be avoided, personal efforts made by nurses to establish their own living standards for positive health behaviors will benefit their quality of life.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.13 no.5
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• pp.51-58
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• 2010

This study was done to recommend a method for conserving the habitat of Amblyotropis verna grown naturally in campus of the Kyungpook National University at Daegu city. Vegetation characteristics and morphological characteristics of each individual were analyzed for the condition of the population at the growing season from May to June in 2010. Totally 11 vegetation data were collected and analyzed, and one vegetation community including Amblyotropis verna (Amblyotropis verna-Zoysia japonica community) was found. We found that the growing condition was not good with severe stamping and disturbance. The location-determining method by PCoA analysis showed the physical texture in soil was a critical factor determining the spatial distribution of the Amblyotropis verna-Zoysia japonica community. And the analysis of morphological characteristics found that light condition and soil hardness were the main ecological factor determining the size and form of each individual. Finally, this study recommend that minimizing impacts by human stamping and artificial disturbance and reducing the water stress were the best ways for the conservation of Amblyotropis verna habitats.

• Korean Journal of Environmental Biology
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• v.22 no.2
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• pp.287-294
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• 2004

Pits and mounds created by windthrow have significant impacts on forest ecosystem. In order to establish initial data base, 80 pits and mounds were sampled and surveyed in 5 fir forests in Nae-Sorak Mountain. Characteristics and forms were surveyed and frequency of tree species appearance were surveyed as well. 4.9％ of surveyed area (0.4 ha) was pits and mounds in El and E2 areas except old areas where survey was done by estimation. E3 area showed the highest proportion, 11.7％ of 0.1 ha of sampling area.