• 한국항해학회지
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• 제16권1호
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• pp.94-97
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• 1992

In this paper, the individual number of the future has depended not only upon the present individual number but upon the present individual age, considering the stochastic process model of individual number when the life span of each individual number and the individual age as a set, this becomes a Markovian. Therefore, in this paper the individual is treated as invariable, without depending upon the whole record of each individual since its birth. As a result, suppose {N(t), t>0} be a counting process and also suppose $Z_n$ denote the life span between the (n-1)st and the nth event of this process, (n{$geq}1$) : that is, when the first individual is established at n=1(time, 0), the Z$Z_n$ at time nth individual breaks, down. Random walk $Z_n$ is $Z_n=X_1+X_2+{\cdots}{\cdots}+X_A, Z_0=0$ So, fixed time t, the stochastic model is made up as follows ; A) Recurrence (Regeneration)number between(0.t) $N_t=max{n ; Z_n{\leq}t}$ B) Forwardrecurrence time(Excess life) $T^-I_t=Z_{Nt+1}-t$ C) Backward recurrence time(Current life) $T^-_t=t-Z_{Nt}$

• 수산해양기술연구
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• 제32권3호
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• pp.235-240
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• 1996

Forecasts of monthly landings of walleye pollock, Theragra chalcogramma, in Korea were carried out by the seasonal Autoregressive Integrated Moving Average(ARlMA) model. The Box - Cox transformation on the walleye pollock catch data handles nonstationary variance. The equation of Box - Cox transformation was Y'=($Y^0.31$_ 1)/0.31. The model identification was determined by minimum AIC(Akaike Information Criteria). And the seasonal ARlMA model is presented (1- O.583B)(1- $B^1$)(l- $B^12$)$Z_t$ =(l- O.912B)(1- O.732$B^12$)et where: $Z_t$=value at month t ; $B^p$ is a backward shift operator, that is, $B^p$$Z_t$=$Z_t$-P; and et= error term at month t, which is to forecast 24 months ahead the walleye pollock landings in Korea. Monthly forecasts of the walleye pollock landings for 1993~ 1994, which were compared with the actual landings, had an absolute percentage error(APE) range of 20.2-226.1 %. Thtal observed annual landings in 1993 and 1994 were 16, 61OM/T and 1O, 748M/T respectively, while the model predicted 10, 7 48M/T and 8, 203M/T(APE 37.0% and 23.7%, respectively).

• 한국수산과학회지
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• 제29권2호
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• pp.143-149
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• 1996

우리나라 멸치어업에서의 1971~1992년 동안의 22년간 월별 어획량 자료를 시계열 분석하여 어획량을 분석, 예측하였다. 시계열 분석은 다른 생물학적, 해양학적, 사회 경제적인 요소가 없어도 단지 어획량 자료만으로 분석과 예측이 가능하다. 첫 20년간인 1971~1990년 사이의 월별 멸치 어획량 자료를 ARIMA 시계열 모형에 적용시켜 구한 결과는 다음과 같다. 로그 (대수) 변환시켰을 때의 ARIMA 모형: $$(1-0.381B)(1-0.027B^{12}+0.141B^{24})(1-B^1)(1-B^{12})Z_t=(1-0.968B)(1-0.727B^{12})e_t$$, Box-Cox 변환시켰을 때의 ARIMA 모형: $$(1-0.431B)(1-B^{12})Z_t=(1-0.882B^{12})e_t$$, 위의 두 모형중 Box-Cox 변환시킨 것이 로그 (대수) 변환시킨 것보다 예측오차가 적었으며, Box-Cox 변환식은 $Y'=(Y^{0.58}-1)/0.58$ 이었다. 위의 두 모형 중 후자의 모형을 이용하여 1991~1992년 사이의 월별 어획량을 예측하였다. 예측 어획량과 실제 어획량과의 월별 오차범위는 1.0~63.2% (1991년에 1.6~63.2%이고, 1992년에는 1.0~60.4%)였다. 예측 어획량이 각 연도별로 148,201M/T과 148,834M/T인데 비해, 실제 어획량은 170,293M/T, 168,234M/T이었다. 2년 동안의 총어획량에 대한 오차는 12.3%였다. 또한 스펙트럼 분석은 순환변동의 주기가 2.2개월, 6.1개월, 10.2개월, 12개월, 14.7개월에서 상대적으로 큰 성분이 있음을 나타내었다 이 순환변동 성분은 적절한 ARIMA 모형을 결정하는 데도 도움이 된다.

• 한국수산과학회지
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• 제28권5호
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• pp.589-598
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• 1995

본 연구는 수온과 크기의 영향을 포함하는 양식굴 C. gigas의 단위시간당 여과수량 산출식을 제시하였다. 여수율의 측정은 폐쇄순환계에서 지표물질의 농도 저감속도를 측정하는 간접법으로 수행되었으며, 지표물질은 배양한 규조류 Chaetoceros calcitrans를 사용하였고, 이 규조의 $chlorophyll-\alpha$양에 직선적으로 비례하는 675nm의 흡광도 값으로 부터 농도감소계수 Z를 구하고, Z를 감소율로 변환하여 수량 V에서 여수율 FR을 산출하였다. $Z=-In(\frac{C_t}{C_0})/t$, $FR=V{\codt}(1-e^{-z})$ 양식굴의 여수율은 다음과 같이 수온 및 개체건조 육중량을 변수로 하는 지수함수식으로 나타낼 수 있다. 여수율은 수온과 더불어 지수함수적으로 증가하며, 상한측 임계온도는 $28-29^{\circ}C$ 사이에 있는 것으로 여겨진다. $\frac{FR}{DW}$, 1/hr/g, dry meat wt = $Exp(0.208{\cdot}T-4.324){\cdot}(DW)^{-0.7771}$, FR, 1/hr/animal = $Exp(0.208{\cdot}T-4.324){\cdot}(DW)^{0.223}$

• Journal of the Korean Society for Industrial and Applied Mathematics
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• 제19권1호
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• pp.69-81
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• 2015

The present paper deals with the determination of temperature, displacement and thermal stresses in a semi-infinite hollow circular disk due to internal heat generation within it. Initially the disk is kept at arbitrary temperature F(r, z). For times t > 0 heat is generated within the circular disk at a rate of g(r, z, t) $Btu/hr.ft^3$. The heat flux is applied on the inner circular boundary (r = a) and the outer circular boundary (r = b). Also, the lower surface (z = 0) is kept at temperature $Q_3(r,t)$ and the upper surface ($Z={\infty}$) is kept at zero temperature. Hollow circular disk extends in the z-direction from z = 0 to infinity. The governing heat conduction equation has been solved by using finite Hankel transform and the generalized finite Fourier transform. As a special case mathematical model is constructed for different metallic disk have been considered. The results are obtained in series form in terms of Bessel's functions. These have been computed numerically and illustrated graphically.

• 환경영향평가
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• 제22권6호
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• pp.591-607
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• 2013

본 연구에서는 생물학적 바이오마커, 물리적 서식지 지표 및 화학적 수질지표를 종합하여 12-메트릭 생태평가 모형을 확립하였고, 도심하천에 적용하여 수생태계 평가를 실시하였다. 생태모형 적용을 위해 도심하천의 상류역의 대조군 지역($C_Z$), 중류의 전이대($T_Z$) 및 하류역의 오염지역(IZ)을 선정한 후, 모델값에 대한 계절별 변이특성을 분석하였다. DNA 손상도 분석은 혈액을 이용한 단세포 전기영동법(Single-cell gel electrophoresis, SCGE)인 Comet assay 지표에 의거한 생지표 메트릭으로 이용되었고, Tail moment, Tail DNA(%) 및 Tail length(${\mu}m$)값이 분석되었다. DNA의 손상은 하류역의 오염지역($I_Z$)에서 분명하게 나타났지만, 대조군($C_Z$) 지역에서는 그렇지 않았다. 개체군 지표로서 비만도 지수인 $C_F$ 값 분석, 체장빈도 분포 지표 및 개체 이상도(Abnormality) 지표가 생물지표로서 이용되었다. 물리적 서식지 지표는 QHEI 모델을 이용하였고, 4개 메트릭이 분석되었다. 화학적 수질지표는 부영양화 지표인 인(P)/질소(N), 화학적 산소요구량 및 전기전도도 지표가 이용되었다. 본 연구를 종합해보면, 12-메트릭 생태모형의 생지표 속성은 대조군($C_Z$)지역에 비해 오염지역($I_Z$)에서 화학적 스트레스 지표(부영양화 지표)에 아주 민감하게 반응 하는 것으로 나타났으며, 또한 이들은 부분적으로 서식지 평가지표에 의해 영향 받는 것으로 분석되었다.

• Journal of Periodontal and Implant Science
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• 제48권3호
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• pp.182-192
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• 2018

Purpose: The purpose of the present study was to validate an experimental model for assessing tissue integration of titanium and zirconia implants with and without buccal dehiscence defects. Methods: In 3 dogs, 5 implants were randomly placed on both sides of the mandibles: 1) Z1: a zirconia implant (modified surface) within the bony housing, 2) Z2: a zirconia implant (standard surface) within the bony housing, 3) T: a titanium implant within the bony housing, 4) Z1_D: a Z1 implant placed with a buccal bone dehiscence defect (3 mm), and 5) T_D: a titanium implant placed with a buccal bone dehiscence defect (3 mm). The healing times were 2 weeks (one side of the mandible) and 6 weeks (the opposite side). Results: The dimensions of the peri-implant soft tissue varied depending on the implant and the healing time. The level of the mucosal margin was located more apically at 6 weeks than at 2 weeks in all groups, except group T. The presence of a buccal dehiscence defect did not result in a decrease in the overall soft tissue dimensions between 2 and 6 weeks ($4.80{\pm}1.31$ and 4.3 mm in group Z1_D, and $4.47{\pm}1.06$ and $4.5{\pm}1.37mm$ in group T_D, respectively). The bone-to-implant contact (BIC) values were highest in group Z1 at both time points ($34.15%{\pm}21.23%$ at 2 weeks, $84.08%{\pm}1.33%$ at 6 weeks). The buccal dehiscence defects in groups Z1_D and T_D showed no further bone loss at 6 weeks compared to 2 weeks. Conclusions: The modified surface of Z1 demonstrated higher BIC values than the surface of Z2. There were minimal differences in the mucosal margin between 2 and 6 weeks in the presence of a dehiscence defect. The present model can serve as a useful tool for studying peri-implant dehiscence defects at the hard and soft tissue levels.

• 한국마린엔지니어링학회:학술대회논문집
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• 한국마린엔지니어링학회 2001년도 추계학술대회 논문집(Proceeding of the KOSME 2001 Autumn Annual Meeting)
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• pp.112-119
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• 2001

Parameter tuning methods by Ziegler-Nickels for control systems are generally classified into Z-N(1) and Z-N(2). The purpose of this paper is to describe what relations exist between methods of Z-N(1) and Z-N(2), or how Z-N(1) method can be originated from Z-N(2) method by analyzing one loop control system of P or PI controller and time delay process. The formulas of Z-N(1) consist of process parameters, L(time delay), $K_m$(gain) and $T_m$(time constant), but Z-N(2) method is based only on the ultimate gain $K_u$ and the ultimate period $T_u$ acquired normally by practical trial without any parameters of Z-N(1). In this paper, for the first step to seek mutual relations, the simple formulas of Z-N(2) are transformed into the formulas composed of the same parameters as Z-N(1) which is derived from the analysis of frequency characteristics. Then, the approximation of the actual ultimate frequency is proposed as important premise in the translation between Z-N(1) and (2). Such equalization and approximation brings a simple approximated formula which can explain how Z-N(1) is originated from the Z-N(2) in the form of formula. And a model system is adopted to compare the approximated formula to Z-N(1) and Z-N(2) methods, the results of which show the effectiveness of the proposals.

• 대한의생명과학회지
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• 제18권3호
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• pp.210-217
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• 2012

Oncolytic viral vectors have shown good candidates for cancer treatment but have many limitations. To improve the therapeutic potential of oncolytic vaccinia virus, we developed a recombinant vaccinia virus expressing the 4-1BBL co-stimulatory molecule or CCL21. 4-1BBL and CCL21 expression was identified by FACS analysis and immunoblotting. rV-4-1BBL vaccination shows significant tumor regression compared to rV-LacZ, but rV-CCL21 shows rapid tumor growth compared to rV-LacZ in the poorly immunogenic B16 murine melanoma model. 4-1BBL expression resulted in the increase of the number of CD8+ T cells and especially the increase of effector (CD62L-CD44+) CD8+ T cells. These data suggest 4-1BBL may be the potential target for enhancement of tumor immunotherapy.

• 대한전기학회:학술대회논문집
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• 대한전기학회 1987년도 전기.전자공학 학술대회 논문집(II)
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• pp.1069-1072
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• 1987

In this paper, we drive useful data from 3-D depth information as input using discontinuity boundary or clustering. And using magnitude and direction of z-gradient we classify the data into adaptable primitive types through intrinsic and stochastical processing. After these processing information is reconstructed for forming data base. And make relationship and standard view position for matching.