• Title/Summary/Keyword: expansion behavior

Search Result 852, Processing Time 0.034 seconds

Thermal-Hydro-Mechanical Behaviors in the Engineered Barrier of a HLW Repository: Engineering-scale Validation Test (고준위폐기물처분장 공학적방벽의 열-수리-역학적 거동 연구: 엔지니어링 규모의 실증실험)

  • Lee, Jae-Owan;Cho, Won-Jin
    • Tunnel and Underground Space
    • /
    • v.17 no.6
    • /
    • pp.464-474
    • /
    • 2007
  • An enhancement in the performance and safety of a high-level waste repository requires a validation of its engineered barrier. An engineering-scale test (named "KENTEX") has been conducted to investigate the thermal-hydro-mechanical behaviors in the engineered barrier of the Korean reference disposal system The validation test started on May 31, 2005 and is still under operation. The experimental data obtained allowed a preliminary and qualitative interpretation of the thermal-hydro-mechanical behaviors in the bentonite blocks. The temperature was higher as it became closer to the heater, while it became lower as it was farther away from the heater. The water content had a higher value in the part close to the hydration surface than that in the heater part. The relative humidity data suggested that a hydration of the bentonite blocks might occur by different drying-wetting processes, depending on their position. The total pressure was continuously increased by the evolution of the saturation front in the bentonite blocks and thereby the swelling pressure. Near the heater region, there was also a significant contribution of the thermal expansion of bentonite and the vapor pressure in the pores of the bentonite blocks.

Thermoelectric Properties of Skutterudite CoSb3 Prepared by Arc Melting (아크용해법으로 제조된 Skutterudite CoSb3의 열전특성)

  • Yu S.W.;Park J.B.;Cho K.W.;Jang K.W.;Ur S.C.;Lee J.I.;Kim I.H.
    • Korean Journal of Materials Research
    • /
    • v.15 no.2
    • /
    • pp.93-96
    • /
    • 2005
  • The arc melting was employed to prepare undoped $CoSb_3$ compounds and their thermoelectric properties were investigated. Specimen annealed at $400^{\circ}C$ for 24 hrs showed sound microstructure. However, considerable voids and cracks were found after annealing at above $500^{\circ}C$. It seems to be attributed to the phase dissociation and thermal expansion due to phase transitions during annealing and cooling. Single phase $\delta-CoSb_3$ was successfully obtained by annealing at $400^{\circ}C$ for 24 hrs. In the case of increasing annealing temperature, phase decompositions occurred. Undoped $CoSb_3$ showed p-type conduction and intrinsic semiconducting behavior at all temperatures examined. Thermoelectric properties were remarkably improved by annealing and they were closely related to phase transitions.

Characterization of the biodegradable behavior for biphasic calcium phosphates using X-ray diffraction and lattice parameter (X-선 회절 및 격자 매개변수를 이용한 biphasic calcium phosphate 분말의 생분 해성 특성평가)

  • Kim, Dong-Hyun;Song, Chang-Weon;Kim, Tae-Wan;Jin, Heoyng-Ho;Park, Hong-Chae;Yoon, Seog-Young
    • Journal of the Korean Crystal Growth and Crystal Technology
    • /
    • v.21 no.4
    • /
    • pp.169-174
    • /
    • 2011
  • Nanoscale-biodegradable behaviors of synthesized biphasic calcium phosphates (BCP) powders were characterized using X-ray diffraction (XRD), lattice parameter, and field emission microscopy (FE-SEM). The calcined BCP powders in vitro tested in Hank's balanced salt solution (pH = 7.4, $36.5^{\circ}C$) for 3 weeks. The calculated unit cell parameters for BCP have shown lattice distortion and expansion as irregular changes in the a and c-axis after in vitro.

A Study on the Difference of Determinants between Behavioral Intentions of Existing and Potential Customers in Cruise Tourism -Focusing on the Region of Incheon- (크루즈관광에서 기존-잠재 고객간 행동의도 결정요인 차이에 관한 연구 -인천지역을 중심으로-)

  • Kim, ByungIl;Kim, HongSeop
    • Journal of Korea Port Economic Association
    • /
    • v.28 no.4
    • /
    • pp.39-57
    • /
    • 2012
  • This study aims to find out the relationship of customer behavioral intention and marketing variables such as service quality and customer satisfaction which are regarded as its determinants. And then this study has suggested what service factors shall be emphasized to induce the latent customers. And it has grouped strategic Schemes on which service variables shall be focused to enhance the existing customer behavioral intentions. This study has found, to the existing customers, only physical environments among 3 dimension components of Service quality significantly affects to the Behavioral intentions. Priorly, marketing efforts, namely, expansion of convenient facilities such as special berth construction is necessary. To the latent customer, service delivery is the most powerful factor to the behavioral intentions. Consequently, frequency of cruise calling, Facilities of shopping and eating, issues and their development of cruise goods and publicity and promotions are needed.

An Expansion of Affective Image Access Points Based on Users' Response on Image (이용자 반응 기반 이미지 감정 접근점 확장에 관한 연구)

  • Chung, Eun Kyung
    • Journal of the Korean BIBLIA Society for library and Information Science
    • /
    • v.25 no.3
    • /
    • pp.101-118
    • /
    • 2014
  • Given the context of rapid developing ubiquitous computing environment, it is imperative for users to search and use images based on affective meanings. However, it has been difficult to index affective meanings of image since emotions of image are substantially subjective and highly abstract. In addition, utilizing low level features of image for indexing affective meanings of image has been limited for high level concepts of image. To facilitate the access points of affective meanings of image, this study aims to utilize user-provided responses of images. For a data set, emotional words are collected and cleaned from twenty participants with a set of fifteen images, three images for each of basic emotions, love, sad, fear, anger, and happy. A total of 399 unique emotion words are revealed and 1,093 times appeared in this data set. Through co-word analysis and network analysis of emotional words from users' responses, this study demonstrates expanded word sets for five basic emotions. The expanded word sets are characterized with adjective expression and action/behavior expression.

Cracks in Tape Cast Oxide Laminar Composites (테이프 캐스팅 산화물 층상 복합체에서의 균열)

  • Kim, Ji-Hyun;Yang, Tae-Young;Lee, Yoon-Bok;Yoon, Seog-Young;Park, Hong-Chae
    • Journal of the Korean Ceramic Society
    • /
    • v.39 no.5
    • /
    • pp.484-489
    • /
    • 2002
  • Hot-pressure sintered laminar composites with alumina/zirconia or mullite/zirconia as an outer layer and alumina/zircon (resulting in reaction-bonded mullite/zirconia during sintering) as an inner layer were fabricated by tape casting and lamination. Various forms of crack were observed in sintered laminar composites, these cracks included channel cracks in the outer layer, transverse cracks in the inner layer and interface cracks debonding interlayer. Based on detailed microscopic observations, the cracks were attributed to thermal expansion mismatch between the oxides consisting of the each layer. In particular, the interlayer and transverse cracks were confirmed in the laminates consisted of the mullite/zirconia system as the outer layers, however, those cracks were not observed in the alumina/zirconia system used. In addition, the crack propagation did not exhibit same behavior in the two kinds of outer layer when the indentation load was applied.

THE EFFECT OF TENSILE FORCE ON DNA AND PROTEIN SYNTHESIS IN BONE CELLS (인장력이 골조직 세포군의 DNA 및 단백합성에 미치는 영향)

  • Kwon, Oh-Sun;Kim, Sang-Cheol
    • The korean journal of orthodontics
    • /
    • v.24 no.4 s.47
    • /
    • pp.933-943
    • /
    • 1994
  • The present study was undertaken to determine the effect of tensile force on DNA and protein biosynthesis in bone cells, and to identify the cell type(s) which primarily respond to external physical force among the heterogenous bone cell populations. As a prerequisite for this study, two bone cell populations which retain fibroblastic and osteoblastic feature were isolated from fetal rat calvaria with sequential enzyme digestion scheme. Tensile force was delivered to each bone cell population by two acrylic resin plates connected with a orthodontic expansion screw during culture period. Rate of DNA and protein synthesis in each bone cell population were assessed by the incorporated radioactivity of $[^3H]-thymidine$ into DNA and $[^3H]-proline$ into fraction of collagenase-digestible protein and noncollagenous protein, respectively. DNA synthesis of osteoblast-like calvarial cell populations was increased significantly by the application of tensile force for 24 hours. In contrast, no alteration in DNA synthesis of fibroblast-like populations could be observed in response to applied force. Tensile force induced the change in protein synthesis of bone cell populations with the same pattern. Total protein and collagen synthesis were increased whithin 24 hours in osteoblast-like populations, but not in fibroblast-like populations by tensile force application. These findings indicate that physical force can affect cellullar activity of the particular cell population, not all cell Populations residing in bone and osteoblasts respond more sensitively than fibroblasts. So osteoblasts can modulate the behavior of other bone cells including osteoclasts by producing several local regulating factors of bone metabolism. In this context, preferential responsiveness of osteoblasts to applied tensile force observed in this study suggests that osteoblasts may play an important role in regulation of physical force-induced remodelling process.

  • PDF

A study on environmental adaptation and expansion of intelligent agent (지능형 에이전트의 환경 적응성 및 확장성)

  • Baek, Hae-Jung;Park, Young-Tack
    • The KIPS Transactions:PartB
    • /
    • v.10B no.7
    • /
    • pp.795-802
    • /
    • 2003
  • To live autonomously, intelligent agents such as robots or virtual characters need ability that recognizes given environment, and learns and chooses adaptive actions. So, we propose an action selection/learning mechanism in intelligent agents. The proposed mechanism employs a hybrid system which integrates a behavior-based method using the reinforcement learning and a cognitive-based method using the symbolic learning. The characteristics of our mechanism are as follows. First, because it learns adaptive actions about environment using reinforcement learning, our agents have flexibility about environmental changes. Second, because it learns environmental factors for the agent's goals using inductive machine learning and association rules, the agent learns and selects appropriate actions faster in given surrounding and more efficiently in extended surroundings. Third, in implementing the intelligent agents, we considers only the recognized states which are found by a state detector rather than by all states. Because this method consider only necessary states, we can reduce the space of memory. And because it represents and processes new states dynamically, we can cope with the change of environment spontaneously.

Behaviour of Foundation Ground with Marine Clay in Anisotropy (이방성을 갖는 해성점토 기초지반의 거동해석)

  • Kim, Myeon-Su;Lee, Kang-Il;Kim, Chan-Ki;Yun, Jung-Mann;Baek, Won-Jin
    • Journal of the Korean Geosynthetics Society
    • /
    • v.14 no.1
    • /
    • pp.11-21
    • /
    • 2015
  • This study aims at investigating of the behavioral characteristics of foundation ground subjected to a strip load in anisotropy. Using marine clays sampled at Shihwa area, a series of laboratory tests including triaxial compressive test, plane strain compressive and expansion tests that allows horizontal deformation only and zero strain (${\varepsilon}_2$) in the direction of intermediate stress (${\sigma}_2$) are conducted. In addition, a numerical analysis using parameters obtained from the tests is carried out. In the numerical analysis, Cam-clay model that simulates the behavior of natural deposited clay properly is adopted. The analysis results show that the vertical displacements of the plane strain compressive tests are relatively larger than those of triaxial compressive tests by 18-25%. Likewise, the horizontal displacements is 13-19% larger.

Measures for Adware and Spyware (애드웨어 및 스파이웨어 대응기법)

  • Kim, Bae-Hyun;Kwon, Moon-Taek
    • Convergence Security Journal
    • /
    • v.6 no.4
    • /
    • pp.41-47
    • /
    • 2006
  • Spyware is any technology that aids in gathering information about a person or organization with-out their knowledge. Software designed to serve advertising, known as adware, can usually be thought of as spyware as well because it almost invariably includes components for tracking and reporting user information. A piece of spyware and adware affect computers which can rapidly become infected with large numbers of spyware and adware components. Users frequently notice from un-wanted behavior and degradation of system performance, such as significant unwanted CPU activity, disk usage, and network traffic which thereby slows down legitimate uses of these resources. The presence of situation will continue because of rapid expansion of Internet usages. Therefore, security solutions, such as anti-adware and anti-spyware, for recovering these malfunction due to the malicious programs must be developed. However, studies on the malicious programs are still not sufficient. Accordingly, this paper has studied the malicious program techniques, based on the results of analysis of present adware and spyware techniques by employing collected samples, and presents efficient measures for blocking and remedying the malicious programs.

  • PDF