• Journal of the Korean GEO-environmental Society
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• v.11 no.5
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• pp.53-60
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• 2010

The comprehensive tests on unsaturated weathered granite soils are carried out to obtain the soil-water characteristic curve that is the one of the essential requisites to study the unsaturated soil. The weathered granite soils were obtained at Palgong mountain in Daegu. The existing test results have been carried out without overburden pressures and volume changes. In this study, the volumetric pressure plate extractor is improved to consider two factors such as overburden pressure and volume change. The applied overburden pressures were 0, 25, 50, 75, 100kPa and volume changes were measured at each phase. he results of this study are summarized as follows: As the overburden pressure increases, the volumetric water content decreases at the same matric suction and the air entry value increases and gradient of curve at the transition zone and the size of the hysteresis loops decreases. As the overburden pressure increases, the degree of saturation increases at the same matric suction and degree of saturation of the wetting curve is higher than that of dry curve. The SWCC with volume changes are slightly larger than those without volume changes. The general equation proposed by Fredlund & Xing(1994) to fit the experimental result of the SWCC indicates good agreement. The empirical parameters a, n, m as overburden pressure show similar inclination as the existing results.

• Korean Journal of Social Welfare
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• v.65 no.1
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• pp.227-245
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• 2013

This study used the third wave of individual data of KReIs(Korean Retirement and Income Study) because the third wave of data only had the necessary variables which fit into this study. The data was collected in 2010 using national random sampling. The target population was adults who are older than 65 and the sample size of this study was 4,080. The factors of successful aging were compared by the recognition of old age (group (1): people who recognize they are not older adults(n=620); group (2): people who recognize they are older adults(n=3,460)). For comparison of each variable by the recognition of old age, t-test, chi-square test and ANCOVA were used depending on the types of variables. To test the effect on the life satisfaction of the factors of successful aging, hierarchical regressions were used for each group. 1) Except for the number of leisure activities, older adults who recognized they were not old(group (1)) had a higher level of factors composing of successful aging than older adults who recognized they were old(group (2)). 2) For group (1), age did not affect their life satisfaction in a statistically significant level, but for group (2) age negatively affected their life satisfaction. 3) The results indicated that cognitive and physical functioning were more important than avoiding disease and disability. 4) For group (2), IADL affected life satisfaction positively in a statistically significant level, but for group (1), IADL did not affect life satisfaction. 5) For group(2), whether they had a job or not affected the life satisfaction differently.

• Journal of the korean academy of Pediatric Dentistry
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• v.40 no.2
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• pp.98-105
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• 2013

The purpose of this study was to investigate the mesiodistal widths at the cervical level of primary second molars in Korean children, and to compare them with commercial rubber dam clamps commonly used in pediatric dentistry. Dental casts of 115 primary and mixed dentition children were studied. Cervical mesiodistal width (C-MD) was measured at the clinical cervical level of each primary second molar from buccal and lingual sides using a digital caliper (Absolute, Mitutoyo, Kawasaki, Japan). The data were compared with mesiodistal widths of rubber dam clamps #203/204, #10/11, and #205 (Dentech, Japan). C-MDs of primary mandibular second molars were larger than those of primary maxillary second molars, and C-MDs at buccal sides were larger than those of lingual sides. All C-MDs showed statistically significant discrepancies to corresponding widths on clamps (p < 0.05). However the amount of discrepancy was mild in maxillary teeth, while up to 1 mm of discrepancy was shown in mandibular teeth. In conclusion, C-MDs measured in this study imply a relatively fair fit of #10/#11 or #203/#204 clamps on primary maxillary second molars, while suggesting our need for a better clamp with proper size for primary mandibular second molars.

• The Journal of the Acoustical Society of Korea
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• v.20 no.2
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• pp.77-85
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• 2001

This paper proposes a method of time-scale modification of polyphonic audio signals based on a sinusoidal model. The signals are modeled with sinusoidal component and noise component. A multiresolution filter bank is designed which splits the input signal into six octave-spaced subbands without aliasing and sinusoidal modeling is applied to each subband signal. To alleviate smearing of transients in time-scale modification a dynamic segmentation method is applied to subbands which determines the analysis-synthesis frame size adaptively to fit time-frequency characteristics of the subband signal. For extracting sinusoidal components and calculating their parameters matching pursuit algorithm is applied to each analysis frame of subband signal. In accordance with spectrum analysis a psychoacoustic model implementing the effect of frequency masking is incorporated with matching pursuit to provide a resonable stop condition of iteration and reduce the number of sinusoids. The noise component obtained by subtracting the synthesized signal with sinusoidal components from the original signal is modeled by line-segment model of short time spectrum envelope. For various polyphonic audio signals the result of simulation shows suggested sinusoidal modeling can synthesize original signal without loss of perceptual quality and do more robust and high quality time-scale modification for large scale factor because of representing transients without any perceptual loss.

• Journal of Korean Society of Industrial and Systems Engineering
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• v.10 no.16
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• pp.101-106
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• 1987

Statistical control charts are useful tools to monitor and control the manufacturing processes and are widely used in most Korean industries. Many Korean companies, however, do not always obtain desired results from the traditional control charts by Shewhart such as the $\bar{X}$-chart, $\bar{X}$-chart, $\bar{X}$-chart, etc. This is partly because the quality charterstics of the process are not distributed normally but are skewed due to the intermittent production, small lot size, etc. In Shewhart $\bar{X}$-chart. which is the most widely used one in Kora, such skewed distributions make the plots to be inclined below or above the central line or outside the control limits although no assignable causes can be found. To overcome such shortcomings in nonnormally distributed processes, a distribution-free type of confidence interval can be used, which should be based on order statistics. This thesis is concerned with the design of control chart based on a sample median which is easy to use in practical situation and therefore properties for nonnormal distributions may be easily analyzed. Control limits and central lines are given for the more famous nonnormal distributions, such as Gamma, Beta, Lognormal, Weibull, Pareto, Truncated-normal distributions. Robustness of the proposed median control chart is compared with that of the $\bar{X}$-chart; the former tends to be superior to the latter as the probability distribution of the process becomes more skewed. The average run length to detect the assignable cause is also compared when the process has a Normal or a Gamma distribution for which the properties of X are easy to verify, the proposed chart is slightly worse than the $\bar{X}$-chart for the normally distributed product but much better for Gamma-distributed products. Average Run Lengths of the other distributions are also computed. To use the proposed control chart, the probability distribution of the process should be known or estimated. If it is not possible, the results of comparison of the robustness force us to use the proposed median control chart based oh a normal distribution. To estimate the distribution of the process, Sturge's formula is used to graph the histogram and the method of probability plotting, $\chi$$^2$-goodness of fit test and Kolmogorov-Smirnov test, are discussed with real case examples. A comparison of the proposed median chart and the $\bar{X}$ chart was also performed with these examples and the median chart turned out to be superior to the $\bar{X}$-chart.

• The KIPS Transactions:PartC
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• v.14C no.5
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• pp.417-424
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• 2007

Mesh networks using WLAN technology have been paid attention as a key wireless access technology. However, many technical issues still exist for its successful deployment. One of those issues is the routing problem that addresses the path setup through a WLAN mesh network for the data exchanges between a station and a wired network. Since the characteristics of a WLAN mesh network can be very dynamic, the use of single routing protocol would not fit for all environments whether it is reactive or proactive. Therefore, it is required to develop an adaptive routing protocol that modifies itself according to the changes in the network parameters. As a logical first step for the development, an analytical model considering all the dynamic features of a WLAN mesh network is required to evaluate the performance of a reactive and a proactive routing scheme. In this paper, we propose an analytical model that makes us scrutinize the impact of the network and station parameters on the performance of each routing protocol. Our model includes the size of a mesh network, the density of stations, mobility of stations. and the duration of network topology change. We applied our model to the AODV that is a representative reactive routing protocol and DSDV that is a representative proactive routing protocol to analyze the tradeoff between AODV and DSDV in dynamic network environments. Our model is expected to help developing an adaptive routing protocol for a WLAN mesh network.

• Journal of the Korean Society of Clothing and Textiles
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• v.15 no.2 s.38
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• pp.139-150
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• 1991

The purpose of this study is to do the Somatotype classification according to the type of shoulder-neck and to give the thinkness of shoulder pad according to them. Therefore this study was measurement body size of 201 and the somatotypes were classified as their plumb line. The standard somatotype of this measurement was classified as 9 type according to its angle of shoulder inclination and neck length. Pads which have different thickness (1 cm, 1.5 cm, 2 cm) were attached to the 9 body type and the set-in sleeve blouse and raglan sleeve blouse were made and tring test and sensory test were accomplished. The results of this study were as follows: 1 . Classification of shoulder-neck relationship. Angles of shoulder inclination ($15^{\circ},\;21^{\circ},\;27^{\circ}$), lock lenaths (10 cm, 12.5 cm, 15 cm) were classi- fied as 3 type each and these types were combined as 9 types. II . The result of angle difference of shoulder inclination according to pad thickness. 1) In case of set-in pad. angle is increased $5.75^{\circ}$ per 1 cm of pad thickness. 2) In case of raglan pad. angle is increased $6.45^{\circ}$ per 1 cm of pad thickness. III. The most fit pad thickness to the 9 types. In case of set-in sleeve blouse. 1) High shoulder-long neck, Standard shoulder-long neck Low shoulder-long neck, Stan-dard shoulder·standard neck. Low shoulder-standard neck: 1.5 cm. 2) High shoulder-standard neck, Standard shoulder-short neck, Low shoulder-short neck: 1 cm. 3) High shoulder-short neck: 0 cm(without pad) In case of raglan sleeve blouse. 4) High shoulder-long neck, Standard shoulder-long neck, Low shoulder·long neck, Stan-dard shoulder-standard neck, Low shoulder-standard neck: 1.5 cm. 5) High shoulder-standard neck, Standard shoulder-short neck, Low-shoulder-short neck: 1 cm. 6) High shoulder-short neck: 0 cm(without pad)

• Proceedings of the Korean Institute of Navigation and Port Research Conference
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• 2009.06a
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• pp.205-209
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• 2009

Recently, the increase of the size of GNP and the expansion of the foreign tour opportunities by the common 5 days work system in a week, reaction of the burden for visiting foreign countries, and expansion of airlines caused the rapid increase of overseas tour but slow increase in the number of foreign tourists, due to the price rise which might impact on the competitive power, and lack of tour infrastructure and attractiveness. As the wide area along the east coast of GyeongBuk Province has great amount of cultural, ocean and natural resources, it helps to get focused the tour industries and maximize the synergy effect through the mutual development coupling the resources and regions. On the basis of the potentials for the growth of east coast area to the international level and the development of local resources, a ocean tour and resort complex for four seasons, which has s strong connection to the local areas resulting the wide tour bond, could help to improve the local economy and balance the development of local province, and furthermore, jump to the level of the center in the East Coast area in the international society. Through the investigation and analysis of the ocean space development status and usage at the advanced foreign countries, the new meaning of the ocean space at the tour and resort complex would be proposed to the relevant local government in fit.

• The Korean Journal of Applied Statistics
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• v.29 no.2
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• pp.331-344
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• 2016

Whole Crop Barley (WCB) is a representative self-sufficient winter annual forage crop, along with Italian Ryegrass (IRG), in Korea. In this study, we examined the path relationship between WCB yield and climate factors such as temperature, precipitation, and sunshine duration using a structural equation model. A Bayesian approach was considered to overcome the limitations of the small WCB sample size. As prior distribution of parameters in Bayesian method, standard normal distribution, the posterior result of structural equation model for WCB, and the posterior result of structural equation model for IRG (which is the most popular winter crop) were used. Also, Heywood case correction in prior distribution was considered to obtain the posterior distribution of parameters; in addition, the best prior to fit the characteristics of winter crops was identified. In our analysis, we found that the best prior was set by using the results of a structural equation model to IRG with Heywood case correction. This result can provide an alternative for research on forage crops that have hard to collect sample data.

• Korean Security Journal
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• no.16
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• pp.119-135
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• 2008

This study is concerned on how much effect to activate private security officers from the attitude of CEO in private security companies. Of course the philosophy of CEO at the work is much important element on the company activity. And in small-medium size private security company the effect of CEO is tremendous because most of decision making comes from CEO and company is operated. The result of the analysis of the survey on the CEO in private security business is as belows. a) Most of them are not satisfied and negative from current situation of private security industry because too many companies are scattered and the expected social understanding is too low even though the company was established by their own decision due to it was fit to their aptitude. b) The job position is estimated not high by socio-economical perspective, which would be improved to get higher because this industry is very future business. c) Most of members of the korea security association are in negative on the policy of the korea security association but to enhance of the activity all the members should be in union. d) Must make and settle down a channel to communicate and cooperate each other between public and private sector of security business.