• Title/Summary/Keyword: Best Fitting

Search Result 315, Processing Time 0.025 seconds

A Study On The Methods Of Managerial Improvement Of The Hotel s Room Sales Promotion (호텔 객실 판매촉진운영 개선방안에 관한 연구)

  • 신형섭
    • Journal of Applied Tourism Food and Beverage Management and Research
    • /
    • v.8
    • /
    • pp.123-144
    • /
    • 1997
  • This study, by setting the systems of room sale promotion, analyzing the actual status and the present working state with its center on the 'RHotel' that is a special grade-two hotel and the sales promotion activities of each type, intends to understand the presentstatus of the hotel and present its problems and the method for improvement. The strategy of salespromotion and the ineffectivenessof the system organization were found to be imminent in the sales promotion activities as its problems, and the importanceis being not attached to the actual substance rather than to the actualresults, such as the advertisement and publicity strategies, the irrationality of sales personnel controland its evaluation method, and therefore, the goal-oriented control is not being takenad its problems are emerging. Therefore, as an improvement plan, we ought to put the plan of the hotel merchandising into action for customers to buy what they want, the establishment of the customer-oriented sales promotionservice and the communication channel using the brand-new managerial skills, systemaizesales promotion method sand strategies, develop the organizational and systematic strategies develop the organizatinal and systemactic strategies and goods for the sake of the image-making and room sales promotion of hotels, develop the activation ways of flexible operation, and also need to develop the skills of sales promotion. Accordingly, by doing irrationalsales activities in the system and the promotion with its center on the sales promotion department, and it sis urgently required that we streng then the comodity developments fitting the hotel's traits, such as uniformpolicy of cost, mass-communicationactivities for sales promotion, the improvement of non-effectiveness, and advertisement of hotel items, and the publishing of public relation books. Therefore, the best weapon for hotels before other purchaseis to be discriminatized from other competitive hotel with theunderstanding of the psychology and activities of customers, and the communicatin with customers, and to set up organicprograms of sales promotionstrategies. Also we must promote our sales in accordance with the desire of new customers, gater the market information of customers, all the time, and systematize the facility improvement, managerial policy, business strategiescorresponding with the desire of customers. By doing so, we are able to seek, at the same time, both the satis faction of customers and the sales maximization of the hotels that will perfrom the activities of sales promotion and management.

  • PDF

Breast Radiotherapy with Mixed Energy Photons; a Model for Optimal Beam Weighting

  • Birgani, Mohammadjavad Tahmasebi;Fatahiasl, Jafar;Hosseini, Seyed Mohammad;Bagheri, Ali;Behrooz, Mohammad Ali;Zabiehzadeh, Mansour;meskani, Reza;Gomari, Maryam Talaei
    • Asian Pacific Journal of Cancer Prevention
    • /
    • v.16 no.17
    • /
    • pp.7785-7788
    • /
    • 2015
  • Utilization of high energy photons (>10MV) with an optimal weight using a mixed energy technique is a practical way to generate a homogenous dose distribution while maintaining adequate target coverage in intact breast radiotherapy. This study represents a model for estimation of this optimal weight for day to day clinical usage. For this purpose, treatment planning computed tomography scans of thirty-three consecutive early stage breast cancer patients following breast conservation surgery were analyzed. After delineation of the breast clinical target volume (CTV) and placing opposed wedge paired isocenteric tangential portals, dosimeteric calculations were conducted and dose volume histograms (DVHs) were generated, first with pure 6MV photons and then these calculations were repeated ten times with incorporating 18MV photons (ten percent increase in weight per step) in each individual patient. For each calculation two indexes including maximum dose in the breast CTV ($D_{max}$) and the volume of CTV which covered with 95% Isodose line ($V_{CTV,95%IDL}$) were measured according to the DVH data and then normalized values were plotted in a graph. The optimal weight of 18MV photons was defined as the intersection point of $D_{max}$ and $V_{CTV,95%IDL}$ graphs. For creating a model to predict this optimal weight multiple linear regression analysis was used based on some of the breast and tangential field parameters. The best fitting model for prediction of 18MV photons optimal weight in breast radiotherapy using mixed energy technique, incorporated chest wall separation plus central lung distance (Adjusted R2=0.776). In conclusion, this study represents a model for the estimation of optimal beam weighting in breast radiotherapy using mixed photon energy technique for routine day to day clinical usage.

Comparison of Survival Prediction of Rats with Hemorrhagic Shocks Using Artificial Neural Network and Support Vector Machine (출혈성 쇼크를 일으킨 흰쥐에서 인공신경망과 지원벡터기계를 이용한 생존율 비교)

  • Jang, Kyung-Hwan;Yoo, Tae-Keun;Nam, Ki-Chang;Choi, Jae-Rim;Kwon, Min-Kyung;Kim, Deok-Won
    • Journal of the Institute of Electronics Engineers of Korea SC
    • /
    • v.48 no.2
    • /
    • pp.47-55
    • /
    • 2011
  • Hemorrhagic shock is a cause of one third of death resulting from injury in the world. Early diagnosis of hemorrhagic shock makes it possible for physician to treat successfully. The objective of this paper was to select an optimal classifier model using physiological signals from rats measured during hemorrhagic experiment. This data set was used to train and predict survival rate using artificial neural network (ANN) and support vector machine (SVM). To avoid over-fitting, we chose the best classifier according to performance measured by a 10-fold cross validation method. As a result, we selected ANN having three hidden nodes with one hidden layer and SVM with Gaussian kernel function as trained prediction model, and the ANN showed 88.9 % of sensitivity, 96.7 % of specificity, 92.0 % of accuracy and the SVM provided 97.8 % of sensitivity, 95.0 % of specificity, 96.7 % of accuracy. Therefore, SVM was better than ANN for survival prediction.

Pharmacokinetics of oxytetracycline in rabbits after intravenous and intramuscular administrations (토끼에서 oxytetracycline의 정맥 및 근육 투여시의 약물동태학)

  • Kim, Eun-jung;Yun, Hyo-in;Park, Seung-chun;Oh, Tae-kwang;Cho, Chun-hyung
    • Korean Journal of Veterinary Research
    • /
    • v.34 no.2
    • /
    • pp.259-266
    • /
    • 1994
  • The study was carried out to determine the pharmacokinetic parameters after intravenous(iv) and intramuscular(im) administration (10mg/kr) in healthy rabbits. The results obtained through the experiments were summarized as follows: 1. Bioassay (Bacillus cereus 11778) was evaluated very useful for the determination of oxytetracycline(OTC) in the rabbit serum and tissues, with the detection limit of $0.125{\mu}g/ml$. 2. The pharmacokinetic profiles of OTC (10mg/kg, iv) in rabbits were best described with a two compartment open model $(C=29.5e^{-4,3t}{\pm}3.6^{-0.2t})$, whereas that of OTC (10mg/kg, im) showed a one compartment curve fitting. 3. Following iv administration, a rapid distribution phase was predominant [$t_{\frac{1}{2}}({\alpha}):1.43{\pm}0.98hr$ (♂), $0.5{\pm}0.1hr$(♀)], and then more slow elimination phase ensued [$t_{\frac{1}{2}}({\beta}):4.52{\pm}0.76hr$(♂), $7.32{\pm}2.52hr$(♀)]. Other computer generated pharmacokinetic values were as follows:C1 [$67.76{\pm}18.59ml/kg/h$(♂), $76.03{\pm}22.98ml/kg/h$ (♀)] Vd [$257.74{\pm}180.47ml/kg$ (♂), $92.33{\pm}23.62$ (♀)] AUC [$25.6{\pm}4.44mgh/L$ (♂), $39.6{\pm}12.13mgh/l$ (♀)]. There were no statistical significance between both sexes for all the parameters at the confidence level of 95%. 4. After im administaration, the absorption from the injection sites was very rapid [ Ka:$0.18{\pm}0.03h^{-1}$ (♂), $0.24{\pm}0.02h^{-1}$ (♀)] followed by a monoexponential elimination fashion. The time to peak blood level (Tmax) were calculated $1.64{\pm}0.15hr$ and $1.34{\pm}0.24hr$, in the male and female, respectively. The peak levels (Cmax) at the corresponding time were $1.69{\pm}0.23{\mu}g/ml$ (♂) and $2.08{\pm}0.16{\mu}g/ml$ (♀), with no statistical differences (p>0.05).

  • PDF

Analysis of the Optimal Degree and Order of Spherical Harmonics for the GNSS Receiver Antenna's PCV Correction (GNSS 수신기 안테나의 PCV 보정 모델 산출을 위한 구면조화함수 최적차수 분석)

  • Kim, Jin Yi;Won, Ji Hye;Park, Kwan Dong;Seo, Seung Woo;Park, Heung Won
    • Journal of Korean Society for Geospatial Information Science
    • /
    • v.22 no.3
    • /
    • pp.113-119
    • /
    • 2014
  • The positioning accuracy of GNSS surveys deteriorates due to various error factor, and many users sometimes ignore Phase Center Variation (PCV) of antennas. IGS provides an ANTEX file which contains PCV correction information to correct for PCVs. But it is not directly applicable because PCV correction information is provided at 5-degree intervals in the azimuth and elevation directions for the case of receiver antennas, and at 1-degree intervals in the nadir angle for the case of satellite antennas. So, we devised new and optimal ways of interpolating PCV in any desired line of sight to the GNSS satellite. We used spherical harmonics fitting methods in terms of the azimuth and elevation angle for interpolation, and found an optimal degree and order. It is shown that the best accuracy was obtained from the 8 by 8 spherical harmonics. If one requires lower burden on computing resources, the order and degree less than 8 could produce resonable accuracy except for 1st and 5th order.

High Efficiency GaN HEMT Power Amplifier Using Harmonic Matching Technique (고조파 정합 기법을 이용한 고효율 GaN HEMT 전력 증폭기)

  • Jin, Tae-Hoon;Kwon, Tae-Yeop;Jeong, Jinho
    • The Journal of Korean Institute of Electromagnetic Engineering and Science
    • /
    • v.25 no.1
    • /
    • pp.53-61
    • /
    • 2014
  • In this paper, we present the design, fabrication and measurement of high efficiency GaN HEMT power amplifier using harmonic matching technique. In order to achieve high efficiency, harmonic load-pull simulation is performed, that is, the optimum load impedances are determined at $2^{nd}$ and $3^{rd}$ harmonic frequencies as well as at the fundamental. Then, the output matching circuit is designed based on harmonic load-pull simulation. The measurement of the fabricated power amplifier shows the linear gain of 20 dB and $P_{1dB}$(1 dB gain compression point) of 33.7 dBm at 1.85 GHz. The maximum power added efficiency(PAE) of 80.9 % is achieved at the output power of 38.6 dBm, which belongs to best efficiency performance among the reported high efficiency power amplifiers. For W-CDMA input signal, the power amplifier shows a PAE of 27.8 % at the average output power of 28.4 dBm, where an ACLR (Adjacent Channel Leakage Ratio) is measured to be -38.8 dBc. Digital predistortion using polynomial fitting was implemented to linearize the power amplifiers, which allowed about 6.2 dB improvement of an ACLR performance.

Burnout Process Model of Social Workers: Analysis of the Paths from the Job-related Stressors, Job-stress and Professional Self-efficacy to Burnout (사회복지사의 소진과정(Burnout Process) 모델 - 직업관련 스트레스 요인, 직무스트레스와 전문직효능성에 의한 소진 경로분석 -)

  • Lee, Myung-Shin
    • Korean Journal of Social Welfare
    • /
    • v.56 no.4
    • /
    • pp.5-34
    • /
    • 2004
  • This study aims to find out the determinants of burnout in order to better understand the burnout process among social workers. For this purpose, a hypothetical model which explains the relationships among 8 job-related stressors (role ambiguity, role overload, difficulties in solving problems of clients, conflict with the clients, lack of support from the supervisor, closed communication pattern, bureaucracy, and lack of accountability), 4 mediators (job-stress, professional role performance, abiding by the agency policy and partiality in service delivery), and 4 dimensions of burnout (physical exhaustion, psychological exhaustion, depersonalization and personal accomplishment) was developed. Using the data collected from 207 social workers, the hypothetical model was tested. For data analysis, a path analysis was used, and the best-fitting model was found(df=66, $x^2$=63.250, GFI=0.962, CFI=1.00). As a result of this study, the following results were found. Burnout among social workers was increased by the 6 job-related stressors(role ambiguity, role overload, difficulties in solving problems of clients, conflict with the clients, lack of support from the supervisor, closed communication pattern). Job-stress, the mediating variable of the emotional path to burnout, increased professional role performance and the abiding by agency policy, and finally increased burnout. On the other hand, professional self-efficacy (which consists of professional role performance, abiding by agency policy and partiality in service delivery), the mediationg variable of the cognitive path to burnout, reduced burnout when the professional role performance was high, and abiding by agency policy and partiality in service delivery were low.

  • PDF

Simulation-Based Stochastic Markup Estimation System $(S^2ME)$ (시뮬레이션을 기반(基盤)으로 하는 영업이윤율(營業利潤率) 추정(推定) 시스템)

  • Yi, Chang-Yong;Kim, Ryul-Hee;Lim, Tae-Kyung;Kim, Wha-Jung;Lee, Dong-Eun
    • Proceedings of the Korean Institute of Building Construction Conference
    • /
    • 2007.11a
    • /
    • pp.109-113
    • /
    • 2007
  • This paper introduces a system, Simulation based Stochastic Markup Estimation System (S2ME), for estimating optimum markup for a project. The system was designed and implemented to better represent the real world system involved in construction bidding. The findings obtained from the analysis of existing assumptions used in the previous quantitative markup estimation methods were incorporated to improve the accuracy and predictability of the S2ME. The existing methods has four categories of assumption as follows; (1) The number of competitors and who is the competitors are known, (2) A typical competitor, who is fictitious, is assumed for easy computation, (3) the ratio of bid price against cost estimate (B/C) is assumed to follow normal distribution, (4) The deterministic output obtained from the probabilistic equation of existing models is assumed to be acceptable. However, these assumptions compromise the accuracy of prediction. In practice, the bidding patterns of the bidders are randomized in competitive bidding. To complement the lack of accuracy contributed by these assumptions, bidding project was randomly selected from the pool of bidding database in the simulation experiment. The probability to win the bid in the competitive bidding was computed using the profile of the competitors appeared in the selected bidding project record. The expected profit and probability to win the bid was calculated by selecting a bidding record randomly in an iteration of the simulation experiment under the assumption that the bidding pattern retained in historical bidding DB manifest revival. The existing computation, which is handled by means of deterministic procedure, were converted into stochastic model using simulation modeling and analysis technique as follows; (1) estimating the probability distribution functions of competitors' B/C which were obtained from historical bidding DB, (2) analyzing the sensitivity against the increment of markup using normal distribution and actual probability distribution estimated by distribution fitting, (3) estimating the maximum expected profit and optimum markup range. In the case study, the best fitted probability distribution function was estimated using the historical bidding DB retaining the competitors' bidding behavior so that the reliability was improved by estimating the output obtained from simulation experiment.

  • PDF

Evaluation of the Radiochromic Film Dosimetry for a Small Curved Interface (휘어진 경계에서의 좁은 영역에 대한 Radiochromic 필름 도시메트리 평가)

  • Kang, Sei-Kwon;Park, Soah;Hwang, Taejin;Cheong, Kwang-Ho;Han, Taejin;Kim, Haeyoung;Lee, Me-Yeon;Kim, Kyoung Ju;Bae, Hoonsik
    • Progress in Medical Physics
    • /
    • v.23 no.4
    • /
    • pp.234-238
    • /
    • 2012
  • A tumor on the eyelid is often treated using a high-energy electron beam, with a metallic eye shield inserted between the eyelid and the eyeball to preserve the patient's sight. Pretreatment quality assurance of the inner eyelid dose on the metallic shield requires a very small dosimetry tool. For enhanced accuracy, a flexible device fitting the curved interface between the eyelid and the shield is also required. The radiochromic film is the best candidate for this device. To measure the doses along the curved interface and small area, a 3-mm-wide strip of EBT2 film was inserted between the phantom eyelid and the shield. After irradiation with 6 MeV electron beams, the film was evaluated for the dose profile. An acrylic eye shield of the same size as the real eye shield was machined, and CT images free from metal artifacts were obtained. Monte Carlo simulation was performed on the CT images, taking into account eye shield material, such as tungsten, aluminum, and steel. The film-based interface dose distribution agreed with the MC calculation within 2.1%. In the small (millimeter scale) and curved region, radiochromic film dosimetry promises a satisfactory result with easy handling.

The Effect of Number of Echoes and Random Noise on T2 Relaxography : Development of 8-Echo CPMG (에코의 개수와 임의 잡음이 T2 이완영상의 구성에 미치는 영향연구 : 8에코 CPMG영상화 펄스열의 개발)

  • 정은기
    • Investigative Magnetic Resonance Imaging
    • /
    • v.2 no.1
    • /
    • pp.67-72
    • /
    • 1998
  • The mapping of the spin-spin relaxation time T2 in pixel-by-pixel was suggested as a quantitative diagnostic tool in medicine. although the CPMG pulse sequence has been known to be the best pulse sequence for T2 measurement in physics NMR, the supplied pulse sequence by the manufacture of MRI system was able to obtain the maximum of 4 CPMG images. Eight or more images with different echo time TEs are required to construct a reliable T2 map, so that two or more acquisitions were required, which easily took more than 10 minutes. 4-echo CPMG imaging pulse sequence was modified to generate the maximum of 8 MR images with evenly spaced echo time TEs. In human MR imaging, since patients tend to move at least several pixels between the different acquisitions, 8-echo CPMG imaging sequence reduces the acquisition time and may remove any mis-regitration of each pixels signal for the fitting of T2. The resultant T2 maps using the theoretically simulated images and using the MR images of the human brain suggested that 8 echo CPMG sequence with short echo spacing such as 17-20 msec can give the reliable T2 map.

  • PDF