• Title/Summary/Keyword: Two stage approach

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Transhiatal versus Transthoracic Esophagectomy for Esophageal Cancer (식도암의 식도열공을 통한 식도절제술과 개흉을 통한 식도절제술의 비교)

  • 박기성;박창원;최세영;이광숙;유영선;이재훈;금동윤
    • Journal of Chest Surgery
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    • v.35 no.4
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    • pp.296-302
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    • 2002
  • The classic approach for esophagectomy is via the combined thoracic and abdominal approach. Controversy exists whether patients with esophageal carcinoma are best managed with Ivor-Lewis esophagectomy(ILO) as combined thoracic and abdominal approach or transhiatal esophagectomy(THO). The THO approach is known to be superior with respect to operative time, severity of leak, morbidity/mortality, and length of stay, but may represent an inferior cancer operation as a result of survival disadvantage due to inadequate mediastinal clearance compared with ILO. Accordingly, we reviewed the results of our esophageal resections to compare these outcome parameters for each operative approach. Material and Method: From January 1993 to July 2001, We performed a retrospective review of all esophagectomies performed at Keimyung University Dongsan ·Medical Center; 27 underwent THO, and 45 underwent ILO Result: The two groups were comparable in terms of age, sex, and stage of the disease. Mean tumor length and mean operative time were 3.81cm and 354 minutes for THO versus 5.31cm and 453 minutes for ILO, respectively (p<0.01 and p<0.001). Respiratory complications were 11.1% for THO versus 35.6% for ILO(p<0.05). Hospital mortality was 11.1% for THO versus 22.2% for ILO. There were no significant differences between THO and ILO with respect to other types of complications, amount of blood transfusion, leak and stricture rates, and hospital stay. Overall long-term survival at 5 years was 37%, respectively. Conclustion: There was no significant difference in long-term survival of patients of both operative approach. ILO had significant difference in respiratory complications associated with hospital mortality. Hence, THO is a valid alternative to ILO for well selected patients. And either approach appears to be acceptable depending on the surgeons, preferences and experiences.

Clinical Experience of Three Dimensional Conformal Radiation Therapy for Non-Small Cell Lung Cancer (비소세포성 폐암에서 3차원 입체조형 방사선 치료 성적)

  • Choi Eun Kyung;Lee Byong Yong;Kang One Chul;Nho Young Ju;Chung Weon Kuu;Ahn Seung Do;Kim Jong Hoon;Chang Hyesook
    • Radiation Oncology Journal
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    • v.16 no.3
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    • pp.265-274
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    • 1998
  • Purpose : This prospective study has been conducted to assess the value of three dimensional conformal radiation therapy (3DCRT) for lung cancer and to determine its potential advantage over current treatment approaches. Specific aims of this study were to 1) find the most ideal 3DCRT technique 2) establish the maximum tolerance dose that can be delivered with 3DCRT and 3) identify patients at risk for development of radiation pneumonitis. Materials and Methods : Beginning in Nov. 1994, 95 patients with inoperable non-small cell lung cancer (stage I; 4, stage II; 1, stage IIIa; 14, stage IIIb; 76) were entered onto this 3D conformal trial Areas of known disease and elective nodal areas were initially treated to 45 Gy and then using 3DCRT technique 65 to 70 Gy of total dose were delivered to the gross disease. Sixty nine patients received 65 Gy of total dose and 26 received 70 Gy Seventy eight patients (82.1$\%$) also received concurrent MVP chemotherapy. 3DCRT plans were compared with 2D plans to assess the adequacy of dose delivery to target volume, dose volume histograms for normal tissue, and normal tissue complication Probabilities (NTCP). Results : Most of plans (78/95) were composed of non-coplanar multiple (4-8) fields. Coplanar segmented conformal therapy was used in 17 pateints, choosing the proper gantry angle which minimize normal lung exposure in each segment. 3DCRT gave the full dose to nearly 100$\%$ of the gross disease target volume in all patients. The mean NTCP for ipsilateral lung with 3DCRT (range; 0.17-0.43) was 68$\%$ of the mean NTCP with 2D treatment planning (range; 0.27-0.66). DVH analysis for heart showed that irradiated volume of heart could be significantly reduced by non-coplanar 3D approach especially in the case of left lower lobe lesion. Of 95 patients evaluable for response, 75 (79$\%$), showed major response including 25 (26$\%$) with complete responses and 50 (53$\%$) with partial responses. One and two rear overall survivals of stage III patients were 62.6$\%$ and 35.2$\%$ respectively. Twenty percent (19/95) of patients had pneumonitis; Eight patients had grade 1 pneumonitis and 11 other patients had grade 2. Comparison of the average of NTCP for lung showed a significant difference between patients with and without radiation pneumonitis. Average NTCP for Patients without complication was 62$\%$ of those with complications. Conclusions : This study showed that non-coplanar multiple fields (4-8) may be one of the ideal plans for 3DCRT for lung cancer. It also suggested that 3DCRT may provide superior delivery of high dose radiation with reduced risk to normal tissue and that NTCP can be used as a guideline for the dose escalation.

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Automatic Fracture Detection in CT Scan Images of Rocks Using Modified Faster R-CNN Deep-Learning Algorithm with Rotated Bounding Box (회전 경계박스 기능의 변형 FASTER R-CNN 딥러닝 알고리즘을 이용한 암석 CT 영상 내 자동 균열 탐지)

  • Pham, Chuyen;Zhuang, Li;Yeom, Sun;Shin, Hyu-Soung
    • Tunnel and Underground Space
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    • v.31 no.5
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    • pp.374-384
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    • 2021
  • In this study, we propose a new approach for automatic fracture detection in CT scan images of rock specimens. This approach is built on top of two-stage object detection deep learning algorithm called Faster R-CNN with a major modification of using rotated bounding box. The use of rotated bounding box plays a key role in the future work to overcome several inherent difficulties of fracture segmentation relating to the heterogeneity of uninterested background (i.e., minerals) and the variation in size and shape of fracture. Comparing to the commonly used bounding box (i.e., axis-align bounding box), rotated bounding box shows a greater adaptability to fit with the elongated shape of fracture, such that minimizing the ratio of background within the bounding box. Besides, an additional benefit of rotated bounding box is that it can provide relative information on the orientation and length of fracture without the further segmentation and measurement step. To validate the applicability of the proposed approach, we train and test our approach with a number of CT image sets of fractured granite specimens with highly heterogeneous background and other rocks such as sandstone and shale. The result demonstrates that our approach can lead to the encouraging results on fracture detection with the mean average precision (mAP) up to 0.89 and also outperform the conventional approach in terms of background-to-object ratio within the bounding box.

Cooperative Sales Promotion in Manufacturer-Retailer Channel under Unplanned Buying Potential (비계획구매를 고려한 제조업체와 유통업체의 판매촉진 비용 분담)

  • Kim, Hyun Sik
    • Journal of Distribution Research
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    • v.17 no.4
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    • pp.29-53
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    • 2012
  • As so many marketers get to use diverse sales promotion methods, manufacturer and retailer in a channel often use them too. In this context, diverse issues on sales promotion management arise. One of them is the issue of unplanned buying. Consumers' unplanned buying is clearly better off for the retailer but not for manufacturer. This asymmetric influence of unplanned buying should be dealt with prudently because of its possibility of provocation of channel conflict. However, there have been scarce studies on the sales promotion management strategy considering the unplanned buying and its asymmetric effect on retailer and manufacturer. In this paper, we try to find a better way for a manufacturer in a channel to promote performance through the retailer's sales promotion efforts when there is potential of unplanned buying effect. We investigate via game-theoretic modeling what is the optimal cost sharing level between the manufacturer and retailer when there is unplanned buying effect. We investigated following issues about the topic as follows: (1) What structure of cost sharing mechanism should the manufacturer and retailer in a channel choose when unplanned buying effect is strong (or weak)? (2) How much payoff could the manufacturer and retailer in a channel get when unplanned buying effect is strong (or weak)? We focus on the impact of unplanned buying effect on the optimal cost sharing mechanism for sales promotions between a manufacturer and a retailer in a same channel. So we consider two players in the game, a manufacturer and a retailer who are interacting in a same distribution channel. The model is of complete information game type. In the model, the manufacturer is the Stackelberg leader and the retailer is the follower. Variables in the model are as following table. Manufacturer's objective function in the basic game is as follows: ${\Pi}={\Pi}_1+{\Pi}_2$, where, ${\Pi}_1=w_1(1+L-p_1)-{\psi}^2$, ${\Pi}_2=w_2(1-{\epsilon}L-p_2)$. And retailer's is as follows: ${\pi}={\pi}_1+{\pi}_2$, where, ${\pi}_1=(p_1-w_1)(1+L-p_1)-L(L-{\psi})+p_u(b+L-p_u)$, ${\pi}_2=(p_2-w_2)(1-{\epsilon}L-p_2)$. The model is of four stages in two periods. Stages of the game are as follows. (Stage 1) Manufacturer sets wholesale price of the first period($w_1$) and cost sharing level of channel sales promotion(${\Psi}$). (Stage 2) Retailer sets retail price of the focal brand($p_1$), the unplanned buying item($p_u$), and sales promotion level(L). (Stage 3) Manufacturer sets wholesale price of the second period($w_2$). (Stage 4) Retailer sets retail price of the second period($p_2$). Since the model is a kind of dynamic games, we try to find a subgame perfect equilibrium to derive some theoretical and managerial implications. In order to obtain the subgame perfect equilibrium, we use the backward induction method. In using backward induction approach, we solve the problems backward from stage 4 to stage 1. By completely knowing follower's optimal reaction to the leader's potential actions, we can fold the game tree backward. Equilibrium of each variable in the basic game is as following table. We conducted more analysis of additional game about diverse cost level of manufacturer. Manufacturer's objective function in the additional game is same with that of the basic game as follows: ${\Pi}={\Pi}_1+{\Pi}_2$, where, ${\Pi}_1=w_1(1+L-p_1)-{\psi}^2$, ${\Pi}_2=w_2(1-{\epsilon}L-p_2)$. But retailer's objective function is different from that of the basic game as follows: ${\pi}={\pi}_1+{\pi}_2$, where, ${\pi}_1=(p_1-w_1)(1+L-p_1)-L(L-{\psi})+(p_u-c)(b+L-p_u)$, ${\pi}_2=(p_2-w_2)(1-{\epsilon}L-p_2)$. Equilibrium of each variable in this additional game is as following table. Major findings of the current study are as follows: (1) As the unplanned buying effect gets stronger, manufacturer and retailer had better increase the cost for sales promotion. (2) As the unplanned buying effect gets stronger, manufacturer had better decrease the cost sharing portion of total cost for sales promotion. (3) Manufacturer's profit is increasing function of the unplanned buying effect. (4) All results of (1),(2),(3) are alleviated by the increase of retailer's procurement cost to acquire unplanned buying items. The authors discuss the implications of those results for the marketers in manufacturers or retailers. The current study firstly suggests some managerial implications for the manufacturer how to share the sales promotion cost with the retailer in a channel to the high or low level of the consumers' unplanned buying potential.

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Development of A Boom Sprayer for Effective Pest-and-Disease Control on Densed Paddy Stems (수도(水稻) 기부(基部) 방제용(防除用) 붐-형(型) 주간(株間) 살포(撒布) 장치(裝置) 개발(開發)에 관(關)한 연구(硏究))

  • Chung, Chang Joo;Chang, Young Chang
    • Journal of Biosystems Engineering
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    • v.10 no.1
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    • pp.13-23
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    • 1985
  • Spraying method from the paddy-field levee is known to give insufficient penetration of the spray droplets to the rice stem of the densely grown plants, which is generally encountered at the last stage of rice growth. This study was intended to investigate the spraying system to solve this existing problem. As an approach, it was attempted to develop the boom-with-nozzle, between-the-row application system. Several types of nozzles and their different arrangements in the boom were tested in the field to measure the penetration-reaching distance and the uniformity of spray droplet distribution. The results of the study are summarized as follows: 1. Field experiments by the spraying method from the paddy-field levee showed to have practically no penetration of the spray droplets to the portion of the plant stem with the normal flow volume generally applied and thus need for improving present spraying method. 2. It was found that, considering both the uniformity of the spray droplet distribution and performance rate, the most efficient type of nozzle in the between-the-row boom-type spraying system was one that has core-insert hollow-cone with some clearance between the cone and tip. 3. When tested by applying the spraying method of between-the-row, the nozzle pressure did not affect the uniformity of spray droplet distribution. However, the nozzle pressure had a positive effect on the penetrating-reaching distance of the facing side of the rice stem and did not affect much on that of the opposite face of the stem. It was also found that the maximum pressure to affect the penetration-reaching distance was about $10kg/cm^2$. 4. The uniformity of the spray droplet distribution in the between-the-row system was greatly affected by the height and orientation of the nozzles in the boom. Based on experimental work for the different type of the boom-with-nozzle arrangements, it is recommended that the position of nozzle is set at about 0.45 m above the ground and two nozzles in the boom are oriented to be faced with each other with some angle such that the droplet stream from the nozzle would not directly face with each other.

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Large eddy simulation of wind loads on a long-span spatial lattice roof

  • Li, Chao;Li, Q.S.;Huang, S.H.;Fu, J.Y.;Xiao, Y.Q.
    • Wind and Structures
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    • v.13 no.1
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    • pp.57-82
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    • 2010
  • The 486m-long roof of Shenzhen Citizens Centre is one of the world's longest spatial lattice roof structures. A comprehensive numerical study of wind effects on the long-span structure is presented in this paper. The discretizing and synthesizing of random flow generation technique (DSRFG) recently proposed by two of the authors (Huang and Li 2008) was adopted to produce a spatially correlated turbulent inflow field for the simulation study. The distributions and characteristics of wind loads on the roof were numerically evaluated by Computational Fluid Dynamics (CFD) methods, in which Large Eddy Simulation (LES) and Reynolds Averaged Navier-Stokes Equations (RANS) Model were employed. The main objective of this study is to explore a useful approach for estimations of wind effects on complex curved roof by CFD techniques. In parallel with the numerical investigation, simultaneous pressure measurements on the entire roof were made in a boundary layer wind tunnel to determine mean, fluctuating and peak pressure coefficient distributions, and spectra, spatial correlation coefficients and probability characteristics of pressure fluctuations. Numerical results were then compared with these experimentally determined data for validating the numerical methods. The comparative study demonstrated that the LES integrated with the DSRFG technique could provide satisfactory prediction of wind effects on the long-span roof with complex shape, especially on separation zones along leading eaves where the worst negative wind-induced pressures commonly occur. The recommended LES and inflow turbulence generation technique as well as associated numerical treatments are useful for structural engineers to assess wind effects on a long-span roof at its design stage.

Buffeting response control of a long span cable-stayed bridge during construction using semi-active tuned liquid column dampers

  • Shum, K.M.;Xu, Y.L.;Guo, W.H.
    • Wind and Structures
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    • v.9 no.4
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    • pp.271-296
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    • 2006
  • The frequency of a traditional tuned liquid column damper (TLCD) depends solely on the length of liquid column, which imposes certain restrictions on its application to long span cable-stayed bridges during construction. The configuration of a cable-stayed bridge varies from different construction stages and so do its natural frequencies. It is thus difficult to apply TLCD with a fixed configuration to the bridge during construction or it is not economical to design a series of TLCD with different liquid lengths to suit for various construction stages. Semi-active tuned liquid column damper (SATLCD) with adaptive frequency tuning capacity is studied in this paper for buffeting response control of a long span cable-stayed bridge during construction. The frequency of SATLCD can be adjusted by active control of air pressures inside the air chamber at the two ends of the container. The performance of SATLCD for suppressing combined lateral and torsional vibration of a real long span cable-stayed bridge during construction stage is numerically investigated using a finite element-based approach. The finite element model of SATLCD is also developed and incorporated into the finite element model of the bridge for predicting buffeting response of the coupled SATLCD-bridge system in the time domain. The investigations show that with a fixed container configuration, the SATLCD with adaptive frequency tuning can effectively reduce buffeting response of the bridge during various construction stages.

A Study for Improved Human Action Recognition using Multi-classifiers (비디오 행동 인식을 위하여 다중 판별 결과 융합을 통한 성능 개선에 관한 연구)

  • Kim, Semin;Ro, Yong Man
    • Journal of Broadcast Engineering
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    • v.19 no.2
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    • pp.166-173
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    • 2014
  • Recently, human action recognition have been developed for various broadcasting and video process. Since a video can consist of various scenes, keypoint approaches have been more attracted than template based methods for real application. Keypoint approahces tried to find regions having motion in video, and made 3-dimensional patches. Then, descriptors using histograms were computed from the patches, and a classifier based on machine learning method was applied to detect actions in video. However, a single classifier was difficult to handle various human actions. In order to improve this problem, approaches using multi classifiers were used to detect and to recognize objects. Thus, we propose a new human action recognition using decision-level fusion with support vector machine and sparse representation. The proposed method extracted descriptors based on keypoint approach from a video, and acquired results from each classifier for human action recognition. Then, we applied weights which were acquired by training stage to fuse each results from two classifiers. The experiment results in this paper show better result than a previous fusion method.

Prospect for the Outbreak of War between U.S and China by Comparing of the U.S-Japan Relationship in the World WarII Era and the Modern U.S-China Relationship (태평양 전쟁 전 미일관계와 현재의 미중관계 비교를 통한 미중간 전쟁 발발 가능성에 관한 연구)

  • Kim, Tae-sung
    • Strategy21
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    • s.40
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    • pp.37-81
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    • 2016
  • This paper aims to use crossover analysis to uncover similarities and differences between the U.S-Japan relationship in the World War II era and the modern U.S-China relationship, and to forecast the possibility of the outbreak of war between U.S and China by applying the steps to war theory. The steps to war theory argues that the probability of the outbreak of war between two states within five years would approach 90 percent, if they have ongoing territorial dispute, alliance, rivalry, and arms race. The comparison exposes some similarities with the territorial dispute, alliance, rivalry, but reveals dissimilarities with arms race. U.S-Japan relationship in the World War II era had the arms race, which does not exist the modern U.S-China Relationship. The result of comparison is that the probability for the Outbreak of War between U.S and China correspond to third stage(Risk Level). it means that the probability for the Outbreak of War between U.S and China is 55%. But, There are four elements(① Perception of Leader ② Mutual dependence of economy ③ Possession of nuclear weapon ④ Ravages of war) that reduce the probability for the Outbreak of War. Considering the four elements, the probability for the Outbreak of War between U.S and China is a slim chance. But the probability for the Outbreak of War between U.S and China is excluded because of territorial dispute, alliance, rivalry. So, This paper suggests three points.(① Developing military options ② Reducing the misconception of intend, ③ Promoting navy exchanges) to prevent of Outbreak of War.

Considerations for patient selection: Prepectoral versus subpectoral implant-based breast reconstruction

  • Yang, Jun Young;Kim, Chan Woo;Lee, Jang Won;Kim, Seung Ki;Lee, Seung Ah;Hwang, Euna
    • Archives of Plastic Surgery
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    • v.46 no.6
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    • pp.550-557
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    • 2019
  • Background In recent years, breast implants have been frequently placed in the subcutaneous pocket, in the so-called prepectoral approach. We report our technique of prepectoral implant-based breast reconstruction (IBR), as well as its surgical and aesthetic outcomes, in comparison with subpectoral IBR. We also discuss relevant considerations and pitfalls in prepectoral IBR and suggest an algorithm for the selection of patients for IBR based on our experiences. Methods We performed 79 immediate breast reconstructions with a breast implant and an acellular dermal matrix (ADM) sling, of which 47 were subpectoral IBRs and 32 were prepectoral IBRs. Two-stage IBR was performed in 36 cases (20 subpectoral, 16 prepectoral), and direct-to-implant IBR in 43 cases (27 prepectoral, 16 subpectoral). The ADM sling supplemented the inferolateral side of the breast prosthesis in the subpectoral group and covered the entire anterior surface of the breast prosthesis in the prepectoral group. Results The postoperative pain score was much lower in the prepectoral group than in the subpectoral group (1.78 vs. 7.17). The incidence of seroma was higher in the prepectoral group (31.3% vs. 6.4%). Other postoperative complications, such as surgical site infection, flap necrosis, implant failure, and wound dehiscence, occurred at similar rates in both groups. Animation deformities developed in 8.5% of patients in the subpectoral group and rippling deformities were more common in the prepectoral group (21.9% vs. 12.8%). Conclusions The indications for prepectoral IBR include moderately-sized breasts with a thick well-vascularized mastectomy flap and concomitant bilateral breast reconstruction with prophylactic mastectomy.