• The Korean Journal of Applied Statistics
• /
• v.29 no.7
• /
• pp.1271-1281
• /
• 2016

Wins above replacement (WAR) is one of the most widely used statistic among sabermatrics statistics that measure the ability of a batter in baseball. WAR has a great advantage that is to represent the attack power of the player and the base running ability, defensive ability as a single value. In this study, we proposed a hitter ability index using the sabermetrics statistics that can replace WAR based on Korea Baseball Record Data of the last three years (2013-2015). First, we calculated Batter ability index through the arithmetic mean method, the weighted average method, principal component regression and selected the method that had high correlation with WAR.

• Journal of The Korean Astronomical Society
• /
• v.50 no.2
• /
• pp.21-27
• /
• 2017

The autoregressive method provides a univariate procedure to predict the future sunspot number (SSN) based on past record. The strength of this method lies in the possibility that from past data it yields the SSN in the future as a function of time. On the other hand, its major limitation comes from the intrinsic complexity of solar magnetic activity that may deviate from the linear stationary process assumption that is the basis of the autoregressive model. By analyzing the residual errors produced by the method, we have obtained the following conclusions: (1) the optimal duration of the past time for the forecast is found to be 8.5 years; (2) the standard error increases with prediction horizon and the errors are mostly systematic ones resulting from the incompleteness of the autoregressive model; (3) there is a tendency that the predicted value is underestimated in the activity rising phase, while it is overestimated in the declining phase; (5) the model prediction of a new Solar Cycle is fairly good when it is similar to the previous one, but is bad when the new cycle is much different from the previous one; (6) a reasonably good prediction of a new cycle can be made using the AR model 1.5 years after the start of the cycle. In addition, we predict the next cycle (Solar Cycle 25) will reach the peak in 2024 at the activity level similar to the current cycle.

• Journal of the Korea Society of Computer and Information
• /
• v.10 no.6 s.38
• /
• pp.269-278
• /
• 2005

To justify the economic impacts of the internet access management is a purpose of this paper. Previous researches on economic justification were reviewed and the internet access management system. sniffer, and firewall were implemented to monitor real-time sessions and to record blocked attempts. This paper suggests the impact factors and measurement methods to justify the economic values of the internet access management system. Finally, this paper Proves that the overall impacts of the internet access management system have a Positive value because filtering mechanisms cause users to lose a small number of URLs including useful information and to diminish refreshment but save users from various risk points and enhance labor productivity.

• Journal of the Korean housing association
• /
• v.13 no.2
• /
• pp.23-29
• /
• 2002

The purpose of this study was to find out the present condition of indoor thermal environment and to investigate the environmental needs of the elderly through the measurement of outdoor and indoor physical thermal environment elements and the questionary survey of the response to thermal environment in two welfare facilities for the aged in Taegu during summer in 2001. The 38 residents among the total of 134 residents were asked to record their feelings. The result of this study was as follows. The indoor thermal environment in the facilities subjected leer this study was seemed to be comfortable comparatively. But the values of mean indoor temperature measured were about 1.6-1.8$^{\circ}C$ higher than that of a existing domestic research suggested as thermal comfort zones for the elderly during summer, and most residents fe1t somewhat hot in inner space. And the value of indoor relative humidity in one facility was out from the range of comfort humidity(40-70%). Also there were differences by the geographical location between the two.

• Animal Systematics, Evolution and Diversity
• /
• v.31 no.3
• /
• pp.153-159
• /
• 2015

A terebellid polychaete identified as Pista shizugawaensis Nishi and Tanaka, 2006, whose species validity has been doubted, is newly reported from the southwest coast of Korea. Korean materials of the present study have several characteristics that agree well with the original description of P. shizugawaensis as follows: two pairs of branchiae on the 2nd and 3rd segments have tufts composed of many dichotomously branched filaments; the nephridial papillae are present on the 6th and 7th segments; the uncini on the anterior and middle thoracic segments possess only long-handled shafts while those on the posterior ones have additional short-handled shafts or lacking shafts; the notosetae are broadly or narrowly winged capillary. The authors examined the taxonomic value of the presence of lateral lobes on the 5th and 6th segments, which has been known as a key characteristic feature of P. shizugawaensis in the classification of Pista species. In the present study, several characteristics such as the shape of notosetae, uncinial shafts in the thoracic segments, and the presence of thin narrow lateral lobes on the 4th segment are suggested as the specific characteristics that help to distinguish P. shizugawaensis from its congeners. A key to Pista species from Korean waters is also provided.

• Atmosphere
• /
• v.17 no.1
• /
• pp.17-26
• /
• 2007

The station relocations, the replacement of instruments, and the change of a procedure for calculating derived climatic quantities from observations are well-known nonclimatic factors that seriously contaminate the worthwhile results in climate study. Prior to embarking on the climatological analysis, therefore, the quality and homogeneity of the utilized data sets should be properly evaluated with metadata. According to the metadata of the Korea Meteorological Administration (KMA), there have been plenty of changes in the procedure computing the daily mean values of temperature, humidity, etc, since 1904. For routine climatological work, it is customary to compute approximate daily mean values for individual days from values observed at fixed hours. In the KMA, fixed hours were totally 5 times changed: at four-hourly, four-hourly interval with additional 12 hour, eight-hourly, six-hourly, three-hourly intervals. In this paper, the homogeneity in the daily mean temperature dataset of the KMA was assessed with the consistency and efficiency of point estimators. We used the daily mean calculated from the 24 hourly readings as a potential true value. Approximate daily means computed from temperatures observed at different fixed hours have statistically different properties. So this inhomogeneity in KMA climate data should be kept in mind if you want to analysis secular aspects of Korea climate using this data set.

• Journal of Society of Preventive Korean Medicine
• /
• v.17 no.2
• /
• pp.179-187
• /
• 2013

Objectives : In many cases, patient's symptoms have been recorded on EMR in natural language instead of medical terminologies. It is possible to build a database by analyzing the symptoms of Korean Medicine(KM) that indicates patient's symptoms in natural language. Using the database, when doctors record patient's symptoms on EMR in natural language, conversely it'll be also possible to extract the symptoms of KM from those natural language. The database will enhance the value of EMR as a medical data. Methods : In this study, we aimed to make data structure of the terminologies that represent the symptoms of KM. The data structure is combinations of smallest unit in natural language. We made the database by analyzing morpheme of the natural language to express the symptoms of KM. Results & Conclusions : By classifying the natural language in 15 features, we made the structure of concept and the data available for morphological analysis.

• Journal of Korea Society of Digital Industry and Information Management
• /
• v.13 no.4
• /
• pp.91-98
• /
• 2017

Previous works for detecting arrhythmia have mostly used nonlinear method such as artificial neural network, fuzzy theory, support vector machine to increase classification accuracy. Most methods require higher computational cost and larger processing time. Therefore it is necessary to design efficient algorithm that classifies PVC(premature ventricular contraction) and decreases computational cost by accurately detecting minimal feature point based on only R peak through optimal R wave. We propose an optimal R wave detection and PVC classification method through extracting minimal feature point in IoT environment. For this purpose, we detected R wave through optimal threshold value and extracted RR interval and R peak pattern from noise-free ECG signal through the preprocessing method. Also, we classified PVC in realtime through RR interval and R peak pattern. The performance of R wave detection and PVC classification is evaluated by using record of MIT-BIH arrhythmia database. The achieved scores indicate the average of 99.758% in R wave detection and the rate of 93.94% in PVC classification.

• The Korean Journal of Physiology
• /
• v.4 no.2
• /
• pp.69-81
• /
• 1970

These studies were carried out on 176 persons ranging in age from 20 to 50 years to determine the basal metabolic rates, energy expenditure of various activities, and daily energy expenditure of service personnel in Korea. The measurements of basal metabolic rates were made on 42 subjects by indirect calorimetry using a Douglas' bag and Scholander's gas analyzer. The energy expenditures of various activities of daily life were also measured. The greatest increase in ratio of energy expenditure in the basis of resting metabolism was 277.3% in floor sopping and the least was 40.9% during hair cutting by beauticians. The assessment of the dailly energy expenditure for each subject was made by the factorial method, using a record of their activities throughout each of 24 hours of every survey day. Certain activities were recorded in minute units. The total daily energy expenditure is the sum of all energy expenditure. This was calculated by multiplying the caloric value of the metabolic rate by the time spent on each activity. The result of the total daily energy expenditure records for 17 occupations are summarized. In respect to the daily energy expenditure, most of the occupations are moderate or light work. But the janiter (F), laundress, cook (F), room maid and nurse's aid do heavy work.

• Proceedings of the KSRS Conference
• /
• v.2
• /
• pp.706-709
• /
• 2006

Cancer is one of the major causes of death; however, the survival rate can be increased if discovered at an early stage for timely treatment. According to the statistics of the World Health Organization of 2002, breast cancer was the most prevalent cancer for all cancers occurring in women worldwide, and it account for 16.8% of entire cancers inflicting Korean women today. In order to classify the type of breast cancer whether it is benign or malignant, this study was conducted with the use of the discriminant analysis and the decision tree of data mining with the breast cancer data disclosed on the web. The discriminant analysis is a statistical method to seek certain discriminant criteria and discriminant function to separate the population groups on the basis of observation values obtained from two or more population groups, and use the values obtained to allow the existing observation value to the population group thereto. The decision tree analyzes the record of data collected in the part to show it with the pattern existing in between them, namely, the combination of attribute for the characteristics of each class and make the classification model tree. Through this type of analysis, it may obtain the systematic information on the factors that cause the breast cancer in advance and prevent the risk of recurrence after the surgery.