• 대한전자공학회논문지
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• 제24권5호
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• pp.849-855
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• 1987

This paper describes an implementation of the absolute moment block truncation coding(AMBTC) in real time for the moving picture data compression. We have realized a system composed of the encoder and decoder, and operated it using an NTSC TV signal. The encoder consists of a 4-1line buffer memory and a data processing block. Besides, there are signal conditioner and a control signal generator. Experimental results show that the quality of the processed image with a data rate of 10Mb/s is slightly degraded, but not objectionable, comparing data rate of 80Mb/s.

• 한국정보통신학회:학술대회논문집
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• 한국해양정보통신학회 2009년도 춘계학술대회
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• pp.891-894
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• 2009

In this paper, a scheme to evaluate the number of users in a WCDMA supporting multi-rate traffic is presented through the calculations of Erlang capacity from a derived blocking probability. It is observed that voice-data Erlang capacities have an inverse linear relationship. When the $E_b/N_o$ decreases from 4 dB to 3 dB within the outage probability of 2 % and at the voice rate of 8 kbps, the results show an increase of 8 Erlang at the data rates of 15 kbps, 4 Erlang at 30 kbps, 2 Erlang at 60 kbps, and 1 Erlang at 120 kbps respectively and an increase of the Erlang capacities through a gradual decrease of the data rates from 960 kbps to 15 kbps. So this is useful for optimizing as a reference of design for the capacity in a WCDMA system.

• 한국통신학회논문지
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• 제33권3B호
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• pp.112-122
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• 2008

블루투스 시스템은 피코넷을 기반으로 네트워크를 형성하여 데이터를 전송한다. 하나의 피코넷에는 하나의 마스터 장치와 최대 일곱 개의 슬레이브 장치로 구성될 수 있다. 폴링기법을 사용한 피코넷의 마스터 장치는 잡 스케줄러를 수행하여 피코넷의 모든 슬레이브 장치들에게 데이터 전송 기회를 제공한다. 최대 데이터 전송률은 두개의 블루투스 장치로 이뤄진 피코넷에서 ACL 링크의 DH5형태의 패킷을 사용할 경우이다(최대 데이터 전송률: 723.2 kb/s). 그러나, 한 개의 마스터 장치와 두 개의 슬레이브 장치로 구성된 피코넷의 경우, 마스터 장치는 접속된 모든 슬레이브 장치에게 동등한 데이터 전송률을 제공해줘야 하기 때문에, 데이터 전송률은 절반(361.6 kb/s)으로 줄어든다. 그리고, 스캐터넷에서의 데이터 전송률은 더욱 낮아(최대 전송률: 302.2 kb/s) 지는 단점이 있다. 본 논문에서는 여러개의 피코넷으로 이루어진 스캐터넷에서의 낮은 데이터 전송률을 해결하기 위하여 "더블피코(DoublePico)"라 불리는 새로운 애드혹 네트워크 형태를 제안한다. 또한, 본 논문에서 제안된 더블피코는 블루투스를 이용한 애드혹 네트워크에서 높은 데이터 전송률(최대 전송률: 457.57 kb/s)을 제공한다.

• 대한간호학회지
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• 제11권2호
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• pp.105-123
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• 1981

This study was carried out during the month of September 1976 to analyse and compare the health complaints of two groups of the university women, those who lived at home and those who lived in the university dormitory. The purpose of the study was to provide basic data required by the university health program for planning related to the health need of women students. The study sample consisted of 434 students living in the dormitory and 381 students living at home enrolled for the fall semester 1976 in a womens university in Seoul. The instrument used for the collection of data was an abridged version of a modified Cornell Medical Index. The questionarre included 35 items related to physical health complaint and 22 items related to mental health complaints. The data was treated by a computer (SPSS) using one way analysis, the Fishers' ratio and Chi-Square test at the 5％ level were used for the test for statistical significance. The interpretation of this study is limited due to the sample which was restricted to one university and not randomly selected. To guide the direction of the study, it was hypothesized that the rate of expressed health problems of students living in the dormitory would be Venter than that of students living at home. The hypothesis was tested and rejected. The following is a summary of the findings; 1. Total health (physical and mental) complaints a. There was no statistically significant difference between the home and dormitory groups with regard to total health complaints expressed. b. The rate of total complaints expressed by the home group significantly higher than dormitory group only among third year students. c. There was no statistically significant between the home and dormitory groups in their satisfaction with their economic situation. d. The home group showed a significantly higher rate of complaints related to the Nervous System compared to that of the dormitory group. 2. Physical health complaints a. Students living at home showed a significantly higher rate of physical complaints than the dormitory group. b. When the year variable was controlled, the third year was the only group which showed a different rate between home and dormitory groups; the home group presented a higher rate. c. Since the year variable seemed to affect the physical complaints those data were further analysed to see whether the specific system areas were operating as variables in each year. The results were as follow: Among the home group, First year students showed a higher rate in Family History of Disease, while the third year students more Nervous System and Cardiovascular System complaints. Among the dormitory group, only fourth year students showed a higher rate in the Skeletal-Muscular System. This was the only area the dormitory group though only for the fourth year students supported the hypothesis. d. When the economic satisfaction variable was controlled, the satisfied group was the only group which showed a different rate between home and dormitory groups; the home group presented higher rate. e. Since the economic satisfaction variable seemed to affect the physical complaints those data were further analyzed to see whether the specific system areas were operating as variables in each economic satisfaction level, but there was no statistically significant difference between home and dormitory groups. 3. Mental health complaints a. There was no significantly difference between home and dormitory groups with regard to mental health complaints expressed. b. When the year variable was controlled the third year group was the only group which showed a different rate between home and dormitory groups; the home group presented a higher rate. c. Since the year variable seemed to affect the mental complaints, those data were further analyzed to see whether the specific system areas were operatings variables in each economic satisfaction level. The result were as follows: Among the home group, the third year students showed higher rates in Inadequacy and Anxiety. d. When the economic satisfaction variable was controlled, the very satisfied group was the only group which showed a different rate between home and dormitory groups: the home group presented a higher rate. Since the economic satisfaction variable seemed to affect the mental complaints, those data were further analysed to see whether the specific system areas were operating as variables in each economic satisfaction level, but there was no statistical significant difference between the home and dormitory groups. Although the social environment of dormitory life differs from family life, there was no difference in the rate of total health problem complaints between the home and dormitory groups but the home group showed a higher rate of physical health complaints than the dormitory group. Possible positive factors influencing dormitory life and negative factors influencing family life affecting health complaints must be explored in order to relate to the health needs of the university health program. This study could not define the causes for the fewer physical complaints of dormitory students living at home. Further study of such causal factors recommended in order to provide the data needed to contribute to a more effective health program.

• 한국산학기술학회논문지
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• 제10권6호
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• pp.1346-1352
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• 2009

자동차 부품의 품질보증 비용은 각 시장의 품질보증 영역(warranty region) 내에서 부품이 고장 날 확률에 따라 달라진다. 부품이 고장 날 확률은 각 시장의 다른 스트레스 조건이 비슷하다고 가정할 때 사용비율(usage-rate)에 영향을 크게 받는다. 그러므로 품질보증 비용은 사용비율을 반영한 고장모형을 수립하고 이를 이용한 확률과정 (stochastic process)을 통하여 예측할 수 있다. 본 논문에서는 사용비율을 선형으로 가정한 후 가속실험 모형을 적용하여 2차원 고장모형을 1차원으로 축소시킨다. 이렇게 1차원으로 축소된 고장모형은 사용비율의 함수로 표현될 수 있으므로 사용비율의 변동에 따른 부품의 고장확률 변동을 설명할 수 있다. 이를 통해 새로운 시장의 사용비율을 알면 실측 데이터가 없다고 하더라도 고장확률 분포를 추정할 수 있고 교체되어야 하는 부품일 경우 재생과정(renewal process)으로 비용을 예측할 수 있다. 응용사례에서 실제 두 시장의 품질보증 데이터를 이용하여 이를 분석해 보았다.

• 한국환경과학회지
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• 제4권5호
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• pp.52-52
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• 1995

The temporal and spatial distribution of atmospheric transmissivity and depletion rate of solar radiation are investigated, and are compared to the concentration of several components of air pollution. The length of the data span is 11 years from 1983 to 1993. The data of radiation and sunshine rate recorded at 20 meteorological standard stations were used, and in order to investigate a relationship between the depletion rate of solar radiation and air pollution, the concentration data of air pollution observed in Seoul, Pusan, Taegu, Taejon and Kwangju were compiled from 1991 to 1993. Regression coefficient a and b vary from 0.100 to 0.209, from 0.464 to 0.691, and their means are 0.163 and 0.533, respectively. Climatological atmospheric transmissivity is ranged from 0.68 to 0.83, and its mean is 0.75. Atmospheric transmissivity is relatively low in Pusan, Taejon, Kwangju and Inchon which have large population and are highly industrialized. However, that in Chinju, Mokpo, Cheju and Sosan appears to be large compared to the aforementioned stations. Insolation rate of clear days varies from 0.71 to 0.58, and its mean is 0.63. Insolation rate of Kangnung and Chinju are higher than those of Seoul and Pusan by 5%. From the correlation coefficients between depletion rate of solar radiation and air pollution concentration, the most significant factors related to the depletion rate of solar radiation is appeared to be TSP followed by $SO_2$. Ozone shows a negative correlation, End $NO_2$ does not show a obvious correlation with the depletion rate of solar radiation.

• 한국환경과학회지
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• 제4권5호
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• pp.437-446
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• 1995

The temporal and spatial distribution of atmospheric transmissivity and depletion rate of solar radiation are investigated, and are compared to the concentration of several components of air pollution. The length of the data span is 11 years from 1983 to 1993. The data of radiation and sunshine rate recorded at 20 meteorological standard stations were used, and in order to investigate a relationship between the depletion rate of solar radiation and air pollution, the concentration data of air pollution observed in Seoul, Pusan, Taegu, Taejon and Kwangju were compiled from 1991 to 1993. Regression coefficient a and b vary from 0.100 to 0.209, from 0.464 to 0.691, and their means are 0.163 and 0.533, respectively. Climatological atmospheric transmissivity is ranged from 0.68 to 0.83, and its mean is 0.75. Atmospheric transmissivity is relatively low in Pusan, Taejon, Kwangju and Inchon which have large population and are highly industrialized. However, that in Chinju, Mokpo, Cheju and Sosan appears to be large compared to the aforementioned stations. Insolation rate of clear days varies from 0.71 to 0.58, and its mean is 0.63. Insolation rate of Kangnung and Chinju are higher than those of Seoul and Pusan by 5%. From the correlation coefficients between depletion rate of solar radiation and air pollution concentration, the most significant factors related to the depletion rate of solar radiation is appeared to be TSP followed by $SO_2$. Ozone shows a negative correlation, End $NO_2$ does not show a obvious correlation with the depletion rate of solar radiation.

• 산업경영시스템학회지
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• 제20권44호
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• pp.129-134
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• 1997

The purpose of this study is to estimate the distribution rate of R&D input on R&D output in major manufacturing industrial sector. The distribution rate is estimated on time-series data for the period 1980 to 1996. The data used in this study can be divided into the two categories. 1) R&D output data (Patent, Utility) 2) R&D input data (R&D expenditure, R&D workers) The raw data of R&D expenditure is transformed into R&D stock. And the specific production function is used to represent the interaction between R&D input and output. The production function shows the maximum rate of R&D output that can be achieved by certain given, technologically possible, R&D input combinations. The main findings can be summarized as follows. 1) There was a diminishing return between R&D input and output$(\alpha+\beta<1). 2) R&D output growth was more affected by R&D expenditures than R&D workers. 3) R&D workers were more contributed highly to Patent granted than Utility model.

• 전기학회논문지
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• 제62권4호
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• pp.562-565
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• 2013

A new variable rate speech coding technique is proposed. The method is based on the observation that the speech signal approximately looks linear for a very short period of time. The information transmitted is the location and data value of inflection points. If the distance between the inflection points is large, the mid point location and its data value are also delivered. Thus, the encoder transmits both the location and the data value for the inflection samples, but the location only for the non-inflection points. The location information is expressed using one bit for each sample, 0 for non-inflection and 1 for inflection point. At the receiver, using the interpolation, the decoder estimates the untransmitted sample values for non-inflection locations from the received sample values for the inflection samples. With 50 % of computational cost of the existing CVSD delta modulation, the proposed method is expected to achieve the data rate of 36 to 38 kbps and the SNR of 10 to 13 dB.

• Communications for Statistical Applications and Methods
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• 제17권4호
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• pp.599-609
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• 2010

확산모형은 금융현상을 모형화하기 위한 방법으로 자주 사용된다. 다양한 확산모형들을 추론하기 위한 다양한 추론기법들이 제안되어져 왔다. 본 연구에서는 시뮬레이션 방법을 통하여 Shoji와 Ozaki (1998)에 의하여 제안된 NLL 방법의 성질을 검토하여 보고, 실제 자료에 적용하게 된다.