• 제목/요약/키워드: R-square

검색결과 1,544건 처리시간 0.028초

파클리탁셀의 잔류 펜탄 제거를 위한 회전증발의 동역학 및 열역학에 관한 연구 (Study on Kinetics and Thermodynamics of Rotary Evaporation of Paclitaxel for Removal of Residual Pentane)

  • 한장훈;지성빈;김예솔;이승현;박서희;김진현
    • Korean Chemical Engineering Research
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    • 제55권6호
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    • pp.807-815
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    • 2017
  • 본 연구에서는 회전증발에서 건조 온도에 따른 파클리탁셀의 잔류 펜탄 제거 효율에 대해 조사하였으며 건조 공정에 대한 동역학 및 열역학적 해석을 수행하였다. 모든 온도(25, 30, 35, 40, $45^{\circ}C$)에서 건조 초기에 많은 양의 잔류용매가 제거되었으며 건조 온도가 증가할수록 건조 효율은 증가하였다. 동역학적 해석을 위해 실험데이터 값을 다섯 종류의 건조 모델식(Newton, Page, Modified Page, Henderson and Pabis, Geometric)에 적용하였으며, 이 중 Henderson and Pabis 모델이 큰 결정계수 값과 작은 평균평방근편차 RMSD 값을 가져 가장 적합함을 확인하였다. 또한 열역학적 해석을 수행한 결과, 회전증발에서의 활성화 에너지 $E_a$는 4.9815 kJ/mol이었으며, 표준 Gibbs 자유에너지 변화(${\Delta}G^0$)는 음수 값인 반면 표준 엔탈피 변화(${\Delta}H^0$)와 표준 엔트로피 변화(${\Delta}S^0$)는 양수 값을 나타내어 건조 공정이 자발적 흡열반응이며 비가역적으로 수행됨을 알 수 있었다.

하악 구치부에 식립한 sintered porous surfaced implants의 후향적 다기관 연구 (A Retrospective Study of Sintered Porous-surfaced Dental Implants in Restoring the Edentulous Posterior Mandible: Up to Eight Years of Functioning)

  • 김우성;안경미;손동석;정희승;신임희
    • 대한치과의사협회지
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    • 제47권12호
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    • pp.823-829
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    • 2009
  • Purpose : The aim of this study was to evaluate the survival rate of sintered porous-surfaced implants placed in the edentulous posterior mandibles, in relation to implant length and diameter, crown-to-implant ratio, and types of prostheses, for a maximum of eight years of functioning. Material and Methods : The study group consisted of 43 partially edentulous patients who visited Catholic University Hospital of Daegu and one private dental clinic. A total of 122 sintered porous-surfaced implants n $Endopore^{(R)}$ (Inn ova Life Sciences, Toronto, Ontario, Canada) -- were placed in the edentulous posterior mandibles, Two diameter sizes (4.1 mm and 5.0 mm) and four lengths (5.0 mm, 7.0 mm, 9.0 mm, and 12.0 mm) were used. One hundred and three implants were splinted and 21 implants were nonsplinted. The survival rates of the implants in relation to length, diameter, crown-to-implant ratio, and types of prostheses were investigated. Statistical data were analyzed using SPSS Win.Ver 14.0 software with the Chi-square test. Results : The survival rate of the 4.1mm diameter implants was 100% and 91.2% for the 5.0mm diameter implants. The survival rates of the implants of differing diameters were found to be statistically different (p=0.005). The survival rates of both the 5.0mm and 7.0 mm length implants were 100%. The survival rate of the 9.0mm length implants was 97.9% and for the 12.0mm length implants was 95.1%. There was no statistical difference in survival rates for the differing lengths of implants. Of the 103 prostheses that were splinted, the survival rate was 98.0%. The survival rate of splinted prostheses was higher than that of the non-splinted prostheses, but was found to be not statistically different. There were no failed cases when the crown-to-implant ratio was under 1.0. When the crown-to-implant ratio was between 1.0 and 1.5, the failure rate of the implants was 6.7%. No failure was recorded with the ratio range of 1.5 to 2.0. Relative to the crown-to-implant ratio of 1.0, the failure rates were statistically different (p=0.048). Discussion and Conclusion : The cumulative survival rate of the porous-surfaced implants placed in the edentulous posterior mandibles was 97.5%. Short porous-surfaced implants showed satisfactory results after a maximum of nine years of functioning in the edentulous posterior mandibles.

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대구시 일부 근로자의 구강검진후 치과진료 이용의사에 영향을 미치는 요인 (Factors Influencing on Intention of Dental Care Utilization after Annual Dental Examination for Workers in Daegu, Korea)

  • 장분자;최연희
    • 치위생과학회지
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    • 제9권5호
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    • pp.579-586
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    • 2009
  • 본 연구는 계속구강건강관리가 잘 이루어지지 않는 근로자를 대상으로 계획된 행동이론에 기초하여 구강질환이 있을 경우 치과치료이용을 하려는 의도에 미치는 요인을 조사를 하였다. 이에 치과의료를 이용할 의도를 높일뿐만 아니라 실제 치과의료 이용으로 실행될 수 있는 방안을 마련하는데 기초자료로 쓰이고자 시도되었다. 연구대상상자는 1,016명 중 현재 치과치료를 받는 환자 53명과 지난 6개월간 치과방문을 경험한 사람 355명을 제외한 총 608명을 대상으로 조사 분석하여 얻은 결론은 다음과 같다. 1. TPB 변인과 의도의 상관관계는 행동에 대한 태도, 주관적 규범, 인지된 행동통제의 순으로 나타났으나 인지된 행동통제는 유의하지 않았다. 2. 치과의료이용 의도에 영향을 미치는 일반적 특성은 경제상태로서 여유가 있다고 생각할수록 의도가 높게 나타났으며, TPB 변인 중에서는 치과의료이용과 관련된 행동에 대한 태도와 주관적 규범이 유의한 영향을 주었다. 3. 일반 선형회귀분석한 결과 모형의 설명력은 21%로 나타났다. 구강질환이 있을 경우 치과의료를 이용할 의도가 높다고 하더라도 실제 상황에서는 행동으로 실행이 되지 않을 가능성이 높을 것으로 간주된다. 하지만 의도가 낮은 사람에 비하여 의도가 높은 사람이 실제 치과의료이용을 할 가능성이 높다. 따라서 의도에 영향을 주는 치과의료이용에 관련된 태도와 주관적 규범이 긍정적으로 형성되며 인식할 수 있도록 구강보건교육을 통하여 동기부여가 되어야 하겠다. 그렇게 위해서는 산업장 구강검진이 일회성 형식에 그치지 않으며 구강질환자는 검진치의사의 강력한 치료권고를 통하여 치과치료를 받을 수 있도록 유도하여야 하고, 계속구강건강관리프로그램이 전면적으로 실행되면서 활성화되어 근로자들의 구강건강증진이 이루어져야 하겠다.

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Characterization of Rice Mutants with Enhanced Susceptibility to Rice Blast

  • Kim, Hye-Kyung;Lee, Sang-Kyu;Cho, Jung-Il;Lee, Sichul;An, Gynheung;Jwa, Nam-Soo;Kim, Byung-Ryun;Cho, Young-Chan;Han, Seong-Sook;Bhoo, Seong-Hee;Lee, Youn-Hyung;Hong, Yeon-Kyu;Yi, Gihwan;Park, Dae-Sup;Hahn, Tae-Ryong;Jeon, Jong-Seong
    • Molecules and Cells
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    • 제20권3호
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    • pp.385-391
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    • 2005
  • As a first step towards identifying genes involving in the signal transduction pathways mediating rice blast resistance, we isolated 3 mutants lines that showed enhanced susceptibility to rice blast KJ105 (91-033) from a T-DNA insertion library of the japonica rice cultivar, Hwayeong. Since none of the susceptible phenotypes co-segregated with the T-DNA insertion we adapted a map-based cloning strategy to isolate the gene(s) responsible for the enhanced susceptibility of the Hwayeong mutants. A genetic mapping population was produced by crossing the resistant wild type Hwayeong with the susceptible cultivar, Nagdong. Chi-square analysis of the $F_2$ segregating population indicated that resistance in Hwayeong was controlled by a single major gene that we tentatively named Pi-hy. Randomly selected susceptible plants in the $F_2$ population were used to build an initial map of Pi-hy. The SSLP marker RM2265 on chromosome 2 was closely linked to resistance. High resolution mapping using 105 $F_2$ plants revealed that the resistance gene was tightly linked, or identical, to Pib, a resistance gene with a nucleotide binding sequence and leucine-rich repeats (NB-LRR) previously isolated. Sequence analysis of the Pib locus amplified from three susceptible mutants revealed lesions within this gene, demonstrating that the Pi-hy gene is Pib. The Pib mutations in 1D-22-10-13, 1D-54-16-8, and 1C-143-16-1 were, respectively, a missense mutation in the conserved NB domain 3, a nonsense mutation in the 5th LRR, and a nonsense mutation in the C terminus following the LRRs that causes a small deletion of the C terminus. These findings provide evidence that NB domain 3 and the C terminus are required for full activity of the plant R gene. They also suggest that alterations of the resistance gene can cause major differences in pathogen specificity by affecting interactions with an avirulence factor.

복부일반촬영시 선원과 검출기간의 거리변화에 따른 영상 화질 및 피폭선량에 관한 연구 (A Study on Patients Dose and Image Quality according to Source to Image receptor Distance in Abdomen Radiography: comparison of ESD measured and DRLs in other countries)

  • 장지성;최원근;정재연;이관섭;하동윤
    • 대한디지털의료영상학회논문지
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    • 제14권2호
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    • pp.39-46
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    • 2012
  • Purpose : The purpose of this study was to reduce Entrance Surface Dose and maintain image quality by changing Source to Image receptor Distance. And we'd like to compare ESD on this study to DRLs in other contries. Materials and Methods : We used indirect DR system(Definium 8000, General Electric, USA)and phantom(ART-200X, Flukebiomedical, USA),glass dosimeters(GD-352M, Asahi Techno Glass, Japan)for this study. The imagies were obtained throuh 80kVp fixed, and different tube currents using AEC mode in $16{\times}16$(inch) field size and changing Source to Image receptor Distance from 100 cm to 130 cm per 10 cm unit. The phantom with attaching 5 glass dosimeters on abdomonal skin was set at supine and erect position as a anterioposterial projection on detector For measuring Entrance Surface Dose. Image analysis was conducted by histograms of Image J(1.46r) which was given from National Institutes of Health(NIH). Results : Due to inverse square law of distance, the tube currents were increasing 42.6 % in supine position and 32.6 % in erect position according to the change of Source to Image receptor Distance. While Entrance Surface Doses were rapidly decreasing 14.2 % in supine position and 29.4 % in erect position according to the change of Source to Image receptor Distance. As the results of histogram using Image J, pixel mean values from 100 cm to 110 cm, 120 cm and 130 cm were decreasing each 1.4%, 2.5%, 2.7%, 4.5%, 2.2 %, 5.8 % in supine, erect position. While standard deviations from 100 cm to 110 cm, 120 cm and 130 cm were increasing each 1.4 %, 2.5 %, 2.5 %, 4.0 %, 2.0 %, 4.9 % Consequently, there are no significant differences in abdomen images taken. Conclusion: As the results described above, we strongly recommend using long Sourceto Image receptor Distance than 100cm that we have been using. So, we should deliver less Entrance Surface Dose to the patients while maintaining image quality in abdomen radiography.

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Development of Kinetic Models Describing Kinetic Behavior of Bacillus cereus and Staphylococcus aureus in Milk

  • Kim, Hyoun Wook;Lee, Sun-Ah;Yoon, Yohan;Paik, Hyun-Dong;Ham, Jun-Sang;Han, Sang-Ha;Seo, Kuk-Hwan;Jang, Aera;Park, Bum-Young;Oh, Mi-Hwa
    • 한국축산식품학회지
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    • 제33권2호
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    • pp.155-161
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    • 2013
  • This study developed predictive models to evaluate the kinetic behaviors of Bacillus cereus and Staphylococcus aureus in milk during storage at various temperatures. B. cereus and S. aureus (3 Log CFU/mL) were inoculated into milk and stored at $10^{\circ}C$, $15^{\circ}C$, $20^{\circ}C$, and $30^{\circ}C$, as well as $5^{\circ}C$, $15^{\circ}C$, $25^{\circ}C$, and $35^{\circ}C$, respectively, while bacterial populations were enumerated. The growth data were fitted to the modified Gompertz model to estimate kinetic parameters, including the maximum specific growth rate (${\mu}_{max}$; Log CFU/[$mL{\cdot}h$]), lag phase duration (LPD; h), lower asymptote ($N_0$; Log CFU/mL), and upper asymptote ($N_{max}$; Log CFU/mL). To describe the kinetic behavior of B. cereus and S. aureus, the parameters were fitted to the square root model as a function of storage temperature. Finally, the developed models were validated with the observed data, and Bias (B) and Accuracy (A) factors were calculated. Cell counts of both bacteria increased with storage time. Primary modeling yielded the following parameters; ${\mu}_{max}$: 0.14-0.75 and 0.06-0.51 Log CFU/mL/h; LPD: 1.78-14.03 and 0.00-1.44 h, $N_0$: 3.10-3.37 and 2.09-3.07 Log CFU/mL, and $N_{max}$: 7.59-8.87 and 8.60-9.32 Log CFU/mL for B. cereus and S. aureus, respectively. Secondary modeling yielded a determination of coefficient ($R^2$) of 0.926.0.996. B factors were 1.20 and 0.94, and A factors were 1.16 and 1.08 for B. cereus and S. aureus, respectively. Thus, the mathematical models developed here should be useful in describing the kinetic behaviors of B. cereus and S. aureus in milk during storage.

PNU CGCM-WRF Chain을 이용한 남한 지역 폭염 장기 계절 예측성 평가 (Evaluation of Long-Term Seasonal Predictability of Heatwave over South Korea Using PNU CGCM-WRF Chain)

  • 김영현;김응섭;최명주;심교문;안중배
    • 대기
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    • 제29권5호
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    • pp.671-687
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    • 2019
  • This study evaluates the long-term seasonal predictability of summer (June, July and August) heatwaves over South Korea using 30-year (1989~2018) Hindcast data of the Pusan National University Coupled General Circulation Model (PNU CGCM)-Weather Research and Forecasting (WRF) chain. Heatwave indices such as Number of Heatwave days (HWD), Heatwave Intensity (HWI) and Heatwave Warning (HWW) are used to explore the long-term seasonal predictability of heatwaves. The prediction skills for HWD, HWI, and HWW are evaluated in terms of the Temporal Correlation Coefficient (TCC), Root Mean Square Error (RMSE) and Skill Scores such as Heidke Skill Score (HSS) and Hit Rate (HR). The spatial distributions of daily maximum temperature simulated by WRF are similar overall to those simulated by NCEP-R2 and PNU CGCM. The WRF tends to underestimate the daily maximum temperature than observation because the lateral boundary condition of WRF is PNU CGCM. According to TCC, RMSE and Skill Score, the predictability of daily maximum temperature is higher in the predictions that start from the February and April initial condition. However, the PNU CGCM-WRF chain tends to overestimate HWD, HWI and HWW compared to observations. The TCCs for heatwave indices range from 0.02 to 0.31. The RMSE, HR and HSS values are in the range of 7.73 to 8.73, 0.01 to 0.09 and 0.34 to 0.39, respectively. In general, the prediction skill of the PNU CGCM-WRF chain for heatwave indices is highest in the predictions that start from the February and April initial condition and is lower in the predictions that start from January and March. According to TCC, RMSE and Skill Score, the predictability is more influenced by lead time than by the effects of topography and/or terrain feature because both HSS and HR varies in different leads over the whole region of South Korea.

프로스타글란딘 $E_1$ 요도좌제의 제조 및 평가 (Preparation and Evaluation of $PGE_1$ Transurethral Suppositories)

  • 김종오;권기철;이종달;최한곤;용철순
    • Journal of Pharmaceutical Investigation
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    • 제30권3호
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    • pp.173-178
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    • 2000
  • The purpose of this work is to develop a transurethral suppository containing prostaglandin $E_1\;(PGE_1)$, which stabilizes the drug, gives no irritation to physiological body and enhances the erectile response of $PGE_1.\;PGE_1$ transurethral suppositories were prepared with various amounts of compositions such as saturated polyglycolysed glyceride $(Suppocire^{\circledR}\;AP,\;SAP)$, polyoxyethylene hydrogenated castor oil (HCO-50) and ethanol. The melting points, viscosities and $PGE_1$ release of the suppositories were investigated. Ocular irritation test was carried out after application of $PGE_1$ suppository to rabbit's eye. The intracavernous pressure (ICP), penile length and duration of erectile response were determined after transurethral administration of $PGE_1$ suppository and compared with those after intracavernosal injection of $PGE_1$ solution to cats. HCO-50 hardly affected the melting points and viscosities of $PGE_1$ suppositories. Additionally, $PGE_1$ transurethral suppositories, whose melting point ranges was $34-35^{\circ}C$, was speedily melted in physiological body. HCO-50 significantly decreased the dissolution rates of $PGE_1$ from the suppositories. Dissolution mechanism analysis showed the release of $PGE_1$ was proportional to the square root of time, indicating that $PGE_1$ might be released from the suppositories by Fickian diffusion. The release rate of $PGE_1$ from $PGE_1$ suppository [PGE1/SAP/HCO-50/ethanol (1/94.5/2.5/2%)] was about 80% within 2 h. This $PGE_1$ suppository gave no significant irritation to the ocular tissue, expecting that it gave no irritation to the urethral tissue less sensive than ocular tissue. Furthermore, $PGE_1$ in this suppository was stable at $4^{\circ}C$ for 2 years. This suppository increased the ICP and penile erection similar to those of injectable $PGE_1$ solution. However, it gave 2.5-fold increased duration of erectile response than injectable $PGE_1$ solution. Our results suggested that it gave more effective erectile response than injectable $PGE_1$ solution in cats. It is concluded that this $PGE_1$ suppository with good safety, excellent stability and enhanced erectile response, could be a more effective and convenient transurethal delivery system of $PGE_1$.

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제수원공 설계를 위한 장기간 연속수수량 추정모형의 개발 - 중심유역을 중심으로 (A Developmont of Numerical Mo del on the Estimation of the Log-term Run-off for the Design of Riverheads Works -With Special Reference to Small and Medium Sijed Catchment Areas-)

  • 엄병현
    • 한국농공학회지
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    • 제29권4호
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    • pp.59-72
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    • 1987
  • Although long-term runoff analysis is important as much as flood analysis in the design of water works, the technological level of the former is relatively lower than that of the latter. In this respect, the precise estimation model for the volume of successive runoff should he developed as soon as possible. Up to now, in Korea, Gajiyama's formula has been widely used in long-term runoff analysis, which has many problems in applying in real situation. On the other hand, in flood analysis, unit hydrograph method has been exclusively used. Therefore, this study aims at trying to apply unit hydrograph method in long-term runoff analysis for the betterment of its estimation. Four test catchment areas were selected ; Maesan area in Namlum river as a representative area of Han river system, Cheongju area in Musim river as one of Geum river system, Hwasun area in Hwasun river as one of Yongsan river system, and Supyung area in Geum river as one of Nakdong river system. In the analysis of unit hydrograph, seperation of effective rainfall was carried out firstly. Considering that effective rainfall and moisture condition of catchrnent area are inside and outside of a phenomenon respectively and the latter is not considered in the analysis, Initial base flow(qb)was selected as an index of moisture condition. At the same time, basic equation(Eq.7) was established, in which qb can take a role as a parameter in relating between cumulative rainfall(P) and cumulative loss of rainfall(Ld). Based on the above equation, computer program for estimation model of qbwas seperately developed according to the range of qb, Developed model was applied to measured hydrographs and hyetographs for total 10 years in 4 test areas and effective rainfall was estimated. Estimation precision of model was checked as shown in Tab- 6 and Fig.8. In the next stage, based on the estimated effective rainfall(R) and runoff(Qd), a runoff distribution ratio was calculated for each teat area using by computerised least square method and used in making unit hydrographs in each test area. Significance of induced hydrographs was tested by checking the relative errors between estimated and measured runoff volume(Tab-9, 10). According to the results, runoff estimation error by unit hydrograph itself was merely 2 or 3 %, but other 2 or 3 % of error proved to be transferred error in the seperation of effective rainfall. In this study, special attentioning point is that, in spite of different river systems and forest conditions of test areas, standardized unit hydrographs for them have very similar curve shape, which can be explained by having similar catchinent characteristics such as stream length, catchinent area, slope, and vegetation intensity. That fact should be treated as important factor ingeneralization of unit hydrograph method.

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특급 호텔 조리 식음료 종사자의 위생 관리 인지도 및 수행도에 관한 연구 (A Study on Sanitation Management Recognition and Employee Performance in the Kitchens and Food and Beverage Departments of Deluxe Hotels)

  • 김보라미;이라래;이미호;이성재;조유진;윤현주;윤기선
    • 동아시아식생활학회지
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    • 제17권6호
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    • pp.943-956
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    • 2007
  • This study was conducted to assess the current status of food safety/sanitation training programs, including HACCP, for kitchen and hall employees at major hotels, as well as how differently the training can affect the employees' recognition and performance of food safety/sanitation management in areas related to the facility, food, and their personal hygiene. A questionnaire for assessing the recognition and performance of sanitation management was developed and distributed to 430 employees currently working in the kitchens and halls of 5 hotels located in Seoul, Korea. A total of 324 questionnaires (kitchen: 138, hall: 186) were subjected to frequency analysis, chi-square tests, one way ANOVA, and Pearson correlation analysis using SPSS/windows software. Ninety-one percent of the respondents had received food safety/sanitation training, which was conducted by a hygienist or a cook once a month. However, only 55% of the respondents had HACCP training. The employees that did not have HACCP training had lower recognition scores than those who had HACCP training, especially in the washing procedures for tablewares, handwashing tools, cross contamination, reheating, and HACCP definitions. Trained, full-time employees received significantly higher recognition and performance scores than untrained, contract, or part-time employees. Significant differences in the recognition and performance scores were found among the employees of the 5 different hotels, indicating various levels for the outcome of their sanitation training. In addition, Pearson's correlation analysis confirmed that the recognition and performance scores were significantly correlated (r=0.473, p<.001). This study indicates that hotel foodservice employees must receive systematic food safety/sanitation training, including HACCP, which provides the foundation for safe foodservice operations.

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