• Title/Summary/Keyword: internal responses

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A study on the average wind load characteristics and wind-induced responses of a super-large straight-cone steel cooling tower

  • Ke, S.T.;Du, L.Y.;Ge, Y.J.;Zhao, L.;Tamura, Y.
    • Wind and Structures
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    • v.25 no.5
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    • pp.433-457
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    • 2017
  • As a novel typical wind-sensitive structure, the wind load and wind-induced structural behaviors of super-large straight-cone cooling towers are in an urgent need to be addressed and studied. A super large straight-cone steel cooling tower (189 m high, the highest in Asia) that is under construction in Shanxi Power Plant in China was taken as an example, for which four finite element models corresponding to four structural types: the main drum; main drum + stiffening rings; main drum + stiffening rings + auxiliary rings (auxiliary rings are hinged with the main drum and the ground respectively); and main drum + stiffening rings + auxiliary rings (auxiliary rings are fixed onto the main drum and the ground respectively), were established to compare and analyze the dynamic properties and force transferring paths of different models. After that, CFD method was used to conduct numerical simulation of flow field and mean wind load around the cooling tower. Through field measurements and wind tunnel tests at home and abroad, the reliability of using CFD method for numerical simulation was confirmed. On the basis of this, the surface flow and trail characteristics of the tower at different heights were derived and the wind pressure distribution curves for the internal and external surfaces at different heights of the tower were studied. Finally, based on the calculation results of wind-induced responses of the four models, the effects of stiffening rings, auxiliary rings, and different connecting modes on the dynamic properties and wind-induced responses of the tower structure were derived and analyzed; meanwhile, the effect mechanism of internal suction on such kind of cooling tower was discussed. The study results could provide references to the structure selection and wind resistance design of such type of steel cooling towers.

Factors that Affect Self-esteem among Vietnam War Veterans (베트남전 참전용사의 자아존중감에 영향을 미치는 요인)

  • 이인수
    • Journal of Families and Better Life
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    • v.22 no.1
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    • pp.11-25
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    • 2004
  • This study was conducted to explore the impacts of involvement in the Vietnam War on the self-esteem of the veterans in their later lives. In this study, 14 Korean male Vietnam War veterans from 55 to 63 years old were asked about the impacts of their war experiences on their self-esteem. From the analysis of the in-depth interviews the following conclusions were drawn: First, the veterans perceived that their self-esteem improved with both internal and external impacts of their activities in Vietnam. The internal aspects that improved the veterans' self-esteem were recalling their positive memories of Vietnam War, such as being on duty at a war front for the sake of our country, doing volunteer work for the villagers, and becoming a masculine heroic figure in the family legend. The external aspects were positive attitudes and responses toward their war activities from their family, friends, and neighbors. Second, they also felt persistently frustrated with their recurring memories of involvement in killing human beings, experiences of negative family and social responses, and the side effects of herbicidal cyanide they suffer. In this article, the following suggestions were made. First, standardized images and good-will episodes of the Vietnam War need to be provided by the government, in order to improve public images on the veterans. Second, intensive adjustment programs for the families of older veterans in special needs should be developed in collaboration with various veterans' societies and family counseling institutions, so that the spouses and children can be relieved from tension-laden contacts with the veterans and prevent violent incidents.

Influence of Internal Resonance on Responses of an Autoparametric Vibration Absorber under Random Excitation (불규칙 가진력을 받는 동흡진기의 내부공진효과)

  • 조덕상;이원경
    • Journal of KSNVE
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    • v.10 no.6
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    • pp.1041-1047
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    • 2000
  • The main objectives of this study are to examine the random response of a vibration absorber system with autoparametric coupling in the neighborhood of internal resonance by Gaussian closure and to compare the results with those obtained by Monte Carlo simulation. The numerical simulation is found to support the main features of the nonlinear modal interaction in the neighborhood of internal resonance conditions. While the Gaussian closure exhibits regions of multiple solutions in the neighborhood of internal resonance, the numerical simulation gives only one solution depending on the assigned initial conditions. The on-off intermittency phenomena of the cantilever mode is observed in the Monte Carlo simulation over a small range of parameter.

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Role of Hospital Medicine in Perioperative Patients: Surgery 101 (수술 전후 환자를 진료하는 내과입원전담전문의를 위한 기초 외과학)

  • Han Sung Lee;Sung Woo Moon
    • The Korean Journal of Medicine
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    • v.99 no.4
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    • pp.192-198
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    • 2024
  • Due to their increasing role, many hospitalists will in the future encounter perioperative patients, either through surgical co-management or when an admitted patient requires surgery. If given the responsibility, hospitalists should focus not only on assessing and addressing daily acute issues related to medical comorbidities, but also possess basic knowledge of the typical physiological responses after surgery, prediction, evaluation, and management of perioperative bleeding, and identification of postoperative complications. Understanding these topics may help mitigate complications and improve the management of perioperative patients.

Influences of Wearing Different Thermal Insulated Clothings on Thermoregulatory Responses from $25^{\circ}C$ Environment to 18$^{\circ}C$ Environment ($25^{\circ}C$환경에서 $18^{\circ}C$환경으로 노출시 보온력이 상이한 의복의 착용이 체온조절 반응에 미치는 영향)

  • 이종민
    • Journal of the Korean Society of Clothing and Textiles
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    • v.22 no.7
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    • pp.826-832
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    • 1998
  • In order to understand the influences of wearing clothings with different thermal insula-tions when men were exposed from $25^{\circ}C$ environment to 18$^{\circ}C$ environment, thermoregulatory responses were measured on 4 healthy female college students. Subjects rested wearing T-shirts, trousers, and socks called LC(total weight 541g) at 25$\pm$1$^{\circ}C$, 50$\pm$5% R.H. and then exposed to the room conditioned in 18$\pm$1$^{\circ}C$, 50$\pm$5$^{\circ}C$ R.H. with LC as it was(LC Type) or with T-shirts, trousers, socks, training wear upper garment, the training wear lower garment called HC (total weight 1368g)(HC Type) for 120 min. The results can be summarized as follows: 1) When subjects were exposed from $25^{\circ}C$ environment to 18$^{\circ}C$ environment, decrease of rectal temperature was significantly smaller in LC Type than in HC Type. 2)Increase of heat production and weight loss had no significant difference between two types of clothing. 3)Internal thermal conductance was higher in HC Type and external thermal conductance was higher in LC Type. Therefore total thermal conductance was higher in LC Type than in HC Type. 4)Decrease of skin temperature was greater in LC Type than in HC Type. 5)Subjects felt colder with LC Type than with HC Type, but did not feel differently in comfort sensation between two types of clothing. It was suggested that less decrease of rectal temperature in LC type inspite of more dry heat loss from body might be ascribed to a shift of blood from the shell area to the core area originating in the vasoconstriction and the lowered internal thermal conductance. In conclu-sion, the importance of the state of internal heat distribution in the homeostasis seemed to be reaffirmed.

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Randomized Control Study of Nedaplatin or Cisplatin Concomitant with Other Chemotherapy in the Treatment of Advanced Non-small Cell Lung Cancer

  • Li, Chun-Hong;Liu, Mei-Yan;Liu, Wei;Li, Dan-Dan;Cai, Li
    • Asian Pacific Journal of Cancer Prevention
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    • v.15 no.2
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    • pp.731-736
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    • 2014
  • Objective: To observe the short-term efficacy, long-term survival time and adverse responses with nedaplatin (NDP) or cisplatin (DDP) concomitant with other chemotherapy in treating non-small cell lung cancer. Materials and Methods: A retrospective, randomized, control study was conducted, in which 619 NSCLC patients in phases III and IV who were initially treated and re-treated were randomly divided into an NDP group (n=294) and a DDP group (n=325), the latter being regarded as controls. Chemotherapeutic protocols (CP/DP/GP/NP/TP) containing NDP or DDP were given to both groups. Patients in both groups were further divided to evaluate the clinical efficacies according to initial and re-treatment stage, pathological pattern, type of combined chemotherapeutic protocols, tumor stage and surgery. Results: The overall response rate (ORR) and disease control rate (DCR) in the NDP group were 48.6% and 95.2%, significantly higher than in the DDP group at 35.1% and 89.2%, respectively (P<0.01). In NSCLC patients with initial treatment, squamous carcinoma and phase III, there were significant differences in ORR and DCR between the groups (P<0.05), while ORR was significant in patients with adenocarcinoma, GP/TP and in phase IIIa (P<0.05). There was also a significant difference in DCR in patients in phase IIIb (P<0.05). According to the statistical analysis of survival time of all patients and of those in clinical phase III, the NDP group survived significantly longer than the DDP group (P<0.01). The rates of decreased hemoglobin and increased creatinine, nausea and vomiting in the NDP group were evidently lower than in DDP group (P<0.05). Conclusion: NDP concomitant with other chemotherapy is effective for treating NSCLC, with higher clinical efficacy than DDP concomitant with chemotherapy, with advantages in prolonging survival time and reducing toxic and adverse responses.

Globular Adiponectin Exerts a Pro-Inflammatory Effect via IκB/NF-κB Pathway Activation and Anti-Inflammatory Effect by IRAK-1 Downregulation

  • Lee, Kyoung-Hee;Jeong, Jiyeong;Woo, Jisu;Lee, Chang-Hoon;Yoo, Chul-Gyu
    • Molecules and Cells
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    • v.41 no.8
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    • pp.762-770
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    • 2018
  • Adiponectin, a hormone produced by adipose tissue, is very abundant in plasma, and its anti- and pro-inflammatory effects are reported. However, the mechanisms of these pro- and anti-inflammatory effects are not fully defined. Herein, we evaluated the dual inflammatory response mechanism of adiponectin in macrophages. Short-term globular adiponectin (gAd) treatment induced $I{\kappa}B{\alpha}$ degradation, $NF-{\kappa}B$ nuclear translocation, and $TNF-{\alpha}$ production in RAW 264.7 cells. Polymyxin B pretreatment did not block gAd-induced $I{\kappa}B{\alpha}$ degradation, and heated gAd was unable to degrade $I{\kappa}B{\alpha}$, suggesting that the effects of gAd were not due to endotoxin contamination. gAd activated IKK and Akt, and inhibition of either IKK or Akt by dominant-negative $IKK{\beta}$ ($DN-IKK{\beta}$) or DN-Akt overexpression blocked gAd-induced $I{\kappa}B{\alpha}$ degradation, suggesting that short-term incubation with gAd mediates inflammatory responses by activating the $I{\kappa}B/NF-{\kappa}B$ and PI3K/Akt pathways. Contrastingly, long-term stimulation with gAd induced, upon subsequent stimulation, tolerance to gAd, lipopolysaccharide, and CpG-oligodeoxynucleotide, which is associated with gAd-induced downregulation of IL-receptor-associated kinase-1 (IRAK-1) due to IRAK-1 transcriptional repression. Conclusively, our findings demonstrate that the pro- and anti-inflammatory responses to gAd in innate immune cells are time-dependent, and mediated by the activation of the $I{\kappa}B/NF-{\kappa}B$ pathway, and IRAK-1 downregulation, respectively.

Interference of Acoustic Signals Due to Internal Waves in Shallow Water

  • Na Young-Nam
    • Proceedings of the Acoustical Society of Korea Conference
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    • spring
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    • pp.189-197
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    • 1999
  • To investigate internal waves (IW) effect on acoustic wave propagation, m analysis is conducted on mode travel time and model simulation. Based on the thermistor string data, it can be shown that the thermocline depth variation may cause travel time difference as much as 4-10 ms between mode 1 and 2 over range 10 km. This travel time difference causes interference among modes and thus fluctuation from range-independent stratified ocean structure. In real situations, however, there exist additionally spatial variation of IW. Model simulation with all modes and simple IW shows clear responses of acoustic signals to IW, amplitude and phase fluctuation.

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Assessment of deformations and internal forces in the suspension bridge under eccentric live loads: Analytical algorithm

  • Zhang, Wenming;Lu, Xiaofan;Chang, Jiaqi;Tian, Genmin;Xia, Lianfeng
    • Structural Engineering and Mechanics
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    • v.80 no.6
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    • pp.749-765
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    • 2021
  • Suspension bridges bear large eccentric live loads in rush hours when most vehicles travel in one direction on the left or right side of the bridge. With the increasing number and weight of vehicles and the girder widening, the eccentric live load effect on the bridge behavior, including bending and distortion of the main girder, gets more pronounced, even jeopardizing bridge safety. This study proposes an analytical algorithm based on multi-catenary theory for predicting the suspension bridge responses to eccentric live load via the nonlinear generalized reduced gradient method. A set of governing equations is derived to solve the following unknown values: the girder rigid-body displacement in the longitudinal direction; the horizontal projection lengths of main cable's segments; the parameters of catenary equations and horizontal forces of the side span cable segments and the leftmost segments of middle span cables; the suspender tensions and the bearing reactions. Then girder's responses, including rigid-body displacement in the longitudinal direction, deflections, and torsion angles; suspenders' responses, including the suspender tensions and the hanging point displacements; main cables' responses, including the horizontal forces of each segment; and the longitudinal displacement of the pylons' tower top under eccentric load can be calculated. The response of an exemplar suspension bridge with three spans of 168, 548, and 168 m is calculated by the proposed analytical method and the finite element method in two eccentric live load cases, and their results prove the former's feasibility. The nonuniform distribution of the live load in the lateral direction is shown to impose a greater threat to suspension bridge safety than that in the longitudinal direction, while some other specific features revealed by the proposed method are discussed in detail.