• Journal of the Korean Data and Information Science Society
• /
• 제3권1호
• /
• pp.47-63
• /
• 1992

Bechhofer and Tamhane(1981) proposed Balanced Treatment Incomplete Block (BTIB) desings for comparing p test treatments with a control treatment in blocks of size ${\kappa}$. Notz and Tamhane(1983) solved the problem about determination of the minimal complete class for ${\kappa}=3$. However there are a number of design parameters for which BTIB designs do not exist. We suggest a new class of designs called Group Divisible Treatment Desings(GDTD's) that is a larger class including BTIB designs as a subclass. In this paper we give the minimal complete classes of generator designs for GDTD's with ${\kappa}=2,\;p{\geq}4(except\;prime\;number)\;and\;{\kappa}=3,\;p=4(2)6$.

• Journal of the Korean Statistical Society
• /
• 제8권2호
• /
• pp.125-130
• /
• 1979

It is well known that $L_2(m)$ type PBIB designs have the Property A, so they are BNAS PBIB designs. However, $L_3(m)$ type PBIB designs are not of type of Property A but do have the factorial structure (Cotter, John, and Smith(1973)). In this paper, the properties of the $L_3(m)$ type PBIB designs are investigated. Extended Property A and fractional BNAS are defined and a solution formula for the treatment effects in the $L_32(m)$ type designs is obtained.

• Communications for Statistical Applications and Methods
• /
• 제28권5호
• /
• pp.411-424
• /
• 2021

Inference following two-stage adaptive designs (also known as two-stage randomization designs) with survival endpoints usually focuses on estimating and comparing survival distributions for the different treatment strategies. The aim is to identify the treatment strategy(ies) that leads to better survival of the patients. The objectives of this study were to assess the performance three commonly cited methods for estimating survival distributions in two-stage randomization designs. We review three non-parametric methods for estimating survival distributions in two-stage adaptive designs and compare their performance using simulation studies. The simulation studies show that the method based on the marginal mean model is badly affected by high censoring rates and response rate. The other two methods which are natural extensions of the Nelson-Aalen estimator and the Kaplan-Meier estimator have similar performance. These two methods yield survival estimates which have less bias and more precise than the marginal mean model even in cases of small sample sizes. The weighted versions of the Nelson-Aalen and the Kaplan-Meier estimators are less affected by high censoring rates and low response rates. The bias of the method based on the marginal mean model increases rapidly with increase in censoring rate compared to the other two methods. We apply the three methods to a leukemia clinical trial dataset and also compare the results.

• 품질경영학회지
• /
• 제38권1호
• /
• pp.42-51
• /
• 2010

For the fractional factorial designs, the resolution-IV designs can be used when we want to estimate the main effects and to investigate the structure of the non-negligible two-factor interaction effects, when the three-factor and higher order interaction effects are all negligible. However we need to add the additional treatment combinations in order to identify the influential interactions for the resolution-IV fractional factorial designs. In this paper we investigate the statistical structure for 3-level resolution-IV designs constructed by fold-over scheme and introduce a method for analyzing the influential two-factor interactions.

• 한국품질경영학회:학술대회논문집
• /
• 한국품질경영학회 2010년도 춘계학술대회
• /
• pp.129-138
• /
• 2010

For the fractional factorial designs, the resolution-IV designs can be used when we want to estimate the main effects and to investigate the structure of the non-negligible two-factor interaction effects, when the three-factor and higher order interaction effects are all negligible. However we need to add the additional treatment combination in order to identify the influential interactions for the resolution-IV fracrtional factorial designs. In this paper we investigate the statistical structure for 3-level resolution-IV designs constructed by fold-over scheme and introduce a method for analyzing the influential two-factor interactions.

• Journal of the Korean Data and Information Science Society
• /
• 제1권
• /
• pp.7-33
• /
• 1990

Bechhofer and Tamhane(1981) developed a theory of optimal incomplete block designs for comparing several treatments with a control. This class of designs is appropriate for comparing simultaneously $p{\geq}2$ test treatments with a control treatment (the so-called multiple comparisons with a control (MCC) problem) when the observations are taken in incomplete blocks of common size $K{\<}p+1$. In this paper we want to extend to partially BTIB designs with two associate classes for the MCC problem. We propose a new class of incomplete block designs that are partially balanced with respect to test treatments. Because the class of designs that we consider is larger than the class of designs in Bechhofer and Tamhane and provides us with designs that improve on the optimal designs in their class. We shall use the abbreviation PBTIB to refer to such designs. We study their structure and give some methods of construction. Also we describe a procedure for making exact joint confidence statements for the MCC problem in PBTIB Designs with two associate classes. We study Optimality, Admissibility considerations in PBTIB designs with two associate classes.

• Asian-Australasian Journal of Animal Sciences
• /
• 제12권4호
• /
• pp.607-628
• /
• 1999

The swine waste industry is growing rapidly along with the world human population. The trend is toward more concentrated piggeries with numbers of herds in the thousands. Associated with these increased herds are large quantities of wastes, including organic matter, inorganic nutrients, and gaseous emissions. The trend in swine waste management is toward treatment of these wastes to minimize negative impact on the health and comfort of workers and animals and the atmosphere, water, and soil environments. Treatment of these wastes has traditionally involved land application, lagoons, oxidation ditches, and conventional batch and continuously stirred reactor designs. More sophisticated treatment systems are being implemented, involving advanced anaerobic digester designs, integrated with solids separation, aerobic polishing of digester effluents, and biological nutrient removal. This review discusses the present and future role of anaerobic processes in piggery waste treatment with emphasis on reactor design, operating and performance parameters, and effluent processing.

• Journal of the Korean Statistical Society
• /
• 제15권2호
• /
• pp.118-126
• /
• 1986

The relationships between combined estimators and generalized least squares estimators in block designs are reviewed. Here combined estimators mean the best linear combination of intrablock and interblock estimaters. It is well known that only for balanced incomplete block designs the combined estimators of Yates and of the generalized least squares estimators give the same result. In this paper, a general form of the combined estimators for treatment effects is derived and it can be seen that such estimators are equivalent to the generalized least squares estimators.

• 응용통계연구
• /
• 제5권2호
• /
• pp.169-179
• /
• 1992

블록 계획에서 요인의 효과를 독립적으로 추정 할 수 있도록 그 효과를 직교되게 구성 했을 때 그 계획을 직교 요인 계획이라 한다. 빈 칸이 없는 요인 행-열 계획의 성분계획들이 직 교된 요인의 성질을 지니면 그 행-열 계획 또한 직교된 요인의 성질이 유지 된다는 사실이 입증되었다. 이러한 이유로 빈 칸이 없는 직교요인 행-열 계획은 직교된 성질을 가지는 일 차원 성분 계획들을 단순히 결합함으로써 만들 수 있다. 그러나, 이러한 관계는 빈 칸이 있 는 요인 행-열 계획에서는 성립되지 않는다. 빈칸이 있는 요인 행-열 계획의 연구는 근래에 와서 그 필요성으로 활발히 진행되고 있다. 본 논문에서는 직교된 요인의 성질을 갖는 빈 칸이 있는 요인 행-열 계획의 일부를 조정 직교된 행-열 계획에서 행과 처리를 바꿈으로 설계해 보았다.

• The Journal of Korean Physical Therapy
• /
• 제14권2호
• /
• pp.98-106
• /
• 2002

To understand the trends in research in the fields of physical therapy, all issues of the Journal of Korean Society of Physical Therapy were reviewed from volume 1 in 1989 to volume 13, number 2 in 2001 in regard to research themes, research objects, and research designs. The number of articles dramatically increased in recent years. Although exercise physiology, biomechanics, and therapeutic exercise were major subjects of interest, alternative treatment modalities such as massage, taping, acupuncture were fields of increasing interests. There were also increasing interests in medical engineering and basic science. Cerebrovascular accidents, elderly people, sportsmen were research objects of increasing frequency. In regard to research designs, experimental research designs such as randomized controlled designs and nonequivalent controlled designs were increasingly adopted in clinical research.