• Title/Summary/Keyword: Quality Performance Rate

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Effect of Final Irrigation Timing before Simulated Dark Shipping on Post-shipping Performance of Potted Phalaenopsis Sogo Yukidian 'V3' (팔레놉시스 분화의 모의수송 전 최종 관수 시기가 수송 후 생육에 미치는 영향)

  • Jeong, Ju Hui;Jeon, Jeong Bin;Kim, Sang Yoon;Oh, Wook
    • Journal of Bio-Environment Control
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    • v.30 no.1
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    • pp.65-71
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    • 2021
  • This study was carried out to investigate the effect of the final irrigation timing (FIT) before packaging for long-term transportation on growth, flowering, and crop quality of Phalaenopsis after simulated dark shipping (SDS). Phalaenopsis Sogo Yukidian 'V3' plants grown in 11 cm-diameter plastic pots filled with potting media (sphagnum moss + bark or only sphagnum moss) were packaged in paper boxes for export at 3.5, 7, 10 days (FIT 3.5, 7,10; Experiment 1) and 4, 6, 8, 10 days (FIT 4, 6, 8, 10; Experiment 2) after the final irrigation and then stored in a growth chamber at 20 ± 1℃ and 70 ± 3% RH created for SDS. After 4 weeks, the plants were taken out and grown in a greenhouse at 23 ± 3℃ and 70 ± 5% RH, and crop characteristics were measured during cultivation. In Experiment 1, the survival rate of FIT 3.5 plants was lower than that of FIT 7 and FIT 10. There was no difference between treatments in days to first flower, the number of florets, and the elongation rate of flower stalks. In Experiment 2, the percentage of rotted leaves was lowest in FIT 6 when before forcing and at 12 weeks after forcing, and that of FIT 8 was similar to FIT 6 when before forcing, but slightly increased after 12 weeks. The percentage of rotted leaves of FIT 10 was highest and that of FIT 4 was also high. There was little difference in flowering characteristics among treatments. In conclusion, the FIT before packaging for long-term (4 weeks) transportation of potted Phalaenopsis 'V3' affected the leaf rot rather than the post-shipping growth and flowering. And it was considered appropriate to set the volumetric water content of the potting media just before packaging to about 30%.

A Study on the Buyer's Decision Making Models for Introducing Intelligent Online Handmade Services (지능형 온라인 핸드메이드 서비스 도입을 위한 구매자 의사결정모형에 관한 연구)

  • Park, Jong-Won;Yang, Sung-Byung
    • Journal of Intelligence and Information Systems
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    • v.22 no.1
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    • pp.119-138
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    • 2016
  • Since the Industrial Revolution, which made the mass production and mass distribution of standardized goods possible, machine-made (manufactured) products have accounted for the majority of the market. However, in recent years, the phenomenon of purchasing even more expensive handmade products has become a noticeable trend as consumers have started to acknowledge the value of handmade products, such as the craftsman's commitment, belief in their quality and scarcity, and the sense of self-esteem from having them,. Consumer interest in these handmade products has shown explosive growth and has been coupled with the recent development of three-dimensional (3D) printing technologies. Etsy.com is the world's largest online handmade platform. It is no different from any other online platform; it provides an online market where buyers and sellers virtually meet to share information and transact business. However, Etsy.com is different in that shops within this platform only deal with handmade products in a variety of categories, ranging from jewelry to toys. Since its establishment in 2005, despite being limited to handmade products, Etsy.com has enjoyed rapid growth in membership, transaction volume, and revenue. Most recently in April 2015, it raised funds through an initial public offering (IPO) of more than 1.8 billion USD, which demonstrates the huge potential of online handmade platforms. After the success of Etsy.com, various types of online handmade platforms such as Handmade at Amazon, ArtFire, DaWanda, and Craft is ART have emerged and are now competing with each other, at the same time, which has increased the size of the market. According to Deloitte's 2015 holiday survey on which types of gifts the respondents plan to buy during the holiday season, about 16% of U.S. consumers chose "homemade or craft items (e.g., Etsy purchase)," which was the same rate as those for the computer game and shoes categories. This indicates that consumer interests in online handmade platforms will continue to rise in the future. However, this high interest in the market for handmade products and their platforms has not yet led to academic research. Most extant studies have only focused on machine-made products and intelligent services for them. This indicates a lack of studies on handmade products and their intelligent services on virtual platforms. Therefore, this study used signaling theory and prior research on the effects of sellers' characteristics on their performance (e.g., total sales and price premiums) in the buyer-seller relationship to identify the key influencing e-Image factors (e.g., reputation, size, information sharing, and length of relationship). Then, their impacts on the performance of shops within the online handmade platform were empirically examined; the dataset was collected from Etsy.com through the application of web harvesting technology. The results from the structural equation modeling revealed that the reputation, size, and information sharing have significant effects on the total sales, while the reputation and length of relationship influence price premiums. This study extended the online platform research into online handmade platform research by identifying key influencing e-Image factors on within-platform shop's total sales and price premiums based on signaling theory and then performed a statistical investigation. These findings are expected to be a stepping stone for future studies on intelligent online handmade services as well as handmade products themselves. Furthermore, the findings of the study provide online handmade platform operators with practical guidelines on how to implement intelligent online handmade services. They should also help shop managers build their marketing strategies in a more specific and effective manner by suggesting key influencing e-Image factors. The results of this study should contribute to the vitalization of intelligent online handmade services by providing clues on how to maximize within-platform shops' total sales and price premiums.

Modeling and Intelligent Control for Activated Sludge Process (활성슬러지 공정을 위한 모델링과 지능제어의 적용)

  • Cheon, Seong-pyo;Kim, Bongchul;Kim, Sungshin;Kim, Chang-Won;Kim, Sanghyun;Woo, Hae-Jin
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.10
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    • pp.1905-1919
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    • 2000
  • The main motivation of this research is to develop an intelligent control strategy for Activated Sludge Process (ASP). ASP is a complex and nonlinear dynamic system because of the characteristic of wastewater, the change in influent flow rate, weather conditions, and etc. The mathematical model of ASP also includes uncertainties which are ignored or not considered by process engineer or controller designer. The ASP is generally controlled by a PID controller that consists of fixed proportional, integral, and derivative gain values. The PID gains are adjusted by the expert who has much experience in the ASP. The ASP model based on $Matlab^{(R)}5.3/Simulink^{(R)}3.0$ is developed in this paper. The performance of the model is tested by IWA(International Water Association) and COST(European Cooperation in the field of Scientific and Technical Research) data that include steady-state results during 14 days. The advantage of the developed model is that the user can easily modify or change the controller by the help of the graphical user interface. The ASP model as a typical nonlinear system can be used to simulate and test the proposed controller for an educational purpose. Various control methods are applied to the ASP model and the control results are compared to apply the proposed intelligent control strategy to a real ASP. Three control methods are designed and tested: conventional PID controller, fuzzy logic control approach to modify setpoints, and fuzzy-PID control method. The proposed setpoints changer based on the fuzzy logic shows a better performance and robustness under disturbances. The objective function can be defined and included in the proposed control strategy to improve the effluent water quality and to reduce the operating cost in a real ASP.

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Effects of Dietary Non-Specific Immuno-Stimulator(NIS) on Growth Performance and Carcass Characteristics in Finishing Pigs (비육돈 사료내 비특이성 면역증강제(NIS)의 급여가 성장 및 도체특성에 미치는 영향)

  • 권오석;김인호;홍종욱;김지훈;민병준;이원백;손경승
    • Food Science of Animal Resources
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    • v.24 no.1
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    • pp.44-49
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    • 2004
  • This study was conducted to evaluate the effects of non-specific immuno-stimulator(NIS) supplementation on growth performance and carcass characteristics in finishing pigs. A total of eighty[Duroc${\times}$Yorkshir${\times}$Landrace] pigs(60.55${\pm}$3.72 kg in average initial body weight) were used for a 9-week assay. Dietary treatments included as follows 1) CON(basal diet), 2) NIS1(basal diet for 6 weeks and 0.05% NIS for 3 weeks), 3) NIS2(basal diet for 3 weeks and 0.05% NIS for 6 weeks) and 4) NIS3(0.05% NIS for 9 weeks). Average daily gain during the feeding period was not significantly different among the treatments (p>0.05). However, average daily feed intake was higher in NIS2 than CON(p<0.05). Backfat thickness did not differ among the treatments(p>0.05). The appearance rate of A or B carcass grade was much higher in NIS1 (58%) and NIS3 (75%) than CON(50%) and NIS2(50%). L*(lightness) value of loin was higher in NIS1 and NIS3 than CON and NIS2. However, there was no effect by dietary NIS(p>0.05). Although a*(redness) value of loin was lower in CON than other treatments, there was no significant difference among the treatments(p>0.05). No remarkable differences were found in sensory properties(marbling, firmness and color) among the treatments. The results from the present study suggest that NIS could be an effective feed additive to improve pork quality. However, further research is needed to investigate effect of carcass characteristics.

The Study of Reducing Radiation Exposure Dose and Comparing SUV According to Applied IRIS (Iterative Reconstruction in Image Space) for PET/CT (PET/CT 검사 시 IRIS (Iterative Reconstruction in Image Space) 적용에 따른 CT 피폭선량 감소와 PET SUV 비교 연구)

  • Do, Yong Ho;Song, Ho Jun;Lee, Hyung Jin;Lee, Hong Jae;Kim, Jin Eui
    • The Korean Journal of Nuclear Medicine Technology
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    • v.16 no.2
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    • pp.29-34
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    • 2012
  • Purpose : Presently, hardwares and softwares for reducing radiation exposure are continually developed for PET/CT examination. Purpose of this study is to evaluate effectiveness of reducing radiation exposure dose of CT and SUV changes of PET when applied each kernel to ACCT (Attenuation Correction Computed Tomography) according to adopted IRIS (Iterative Reconstruction in Image Space) software. Materials and Methods : Biograph mCT (Siemens, Germany) was used as a PET/CT scanner. Using AAPM CT performance phantom, from standard (120 kVp, 100 mAs), 7 scans were conducted by reducing 15 mAs each. After image reconstruction by FBP (Filtered Back Projection) and IRIS, noise and spatial resolution were evaluated. The same method was applied to anthropomorphic chest phantom and acquired images were compared. NEMA IEC body phantom was used for SUV evaluation. Injected dose rate for hot sphere (hot) and background cylinder (BKG) were 1:8. CT dose condition (120 kVp, 50 mAs) was the same for each scan and PET scan durations were 1, 2, 3 and 4min. After scanning, each kernel of IRIS was applied to ACCT. And PET images were reconstructed by ACCT adopted IRIS for comparing SUV changes. Results : AAPM phantom test for noise evaluation, SD for FBP 100 mAs, IRIS 55 mAs were 8.8 and 8.9. FBP 85 mAs, IRIS 40 mAs were 9.5 and 9.7. FBP 70 mAs, IRIS 25 mAs were 11.9 and 11.1. Above mAs condition for FBP and IRIS, SD showed similar values. And for spatial resolution test, there was no significant difference. For chest phantom test, when applied the same mAs and kernel to both of FBP and IRIS, every applied kernels showed reduced noise. Lower mAs and higher kernel value showed higher noise reduction. There was no considerable difference only except for I70 very sharp kernel for SUV comparison using NEMA IEC body phantom. Conclusion : In this study, low mAs (55 mAs) applied IRIS and standard mAs (100 mAs) applied FBP showed similar noise. And only except for I70 kernel, there was no significant SUV changes. It is possible to reduce needless radiation exposure and acquire better image quality than FBP's through applying appropriate kernel of IRIS to PET/CT.

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Influences of Feeding Seleniferous Whole Crop Barley on Growth Performance, Blood and Carcass Characteristics, and Tissue Selenium Deposition in Finishing Barrows (셀레늄함유 청보리 급여가 거세비육돈의 생산성, 혈액 및 도체특성, 조직 내 셀레늄 축적에 미치는 영향)

  • HwangBo, Soon;Jo, Ik Hwan;Kim, Guk Won;Choi, Chang Weon;Lee, Sung Hoon;Han, Ouk Kyu;Park, Tae Il;Choi, In Bae
    • Food Science of Animal Resources
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    • v.32 no.6
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    • pp.828-834
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    • 2012
  • The present study has been conducted to investigate the effects of feeding seleniferous whole crop barley (WCB) to finishing pigs on their growth performance, blood and carcass characteristics as well as on tissue selenium deposition. A total of 40 cross-bred barrows ((Landrace${\times}$Yorkshire)${\times}$Duroc) were allotted to five replicates of four treatments. Each replicate was arranged to 2 pigs per pen; the experimental period lasted for 6 weeks. The finishing pigs were fed diets containing 0.1 (non-seleniferous WCB as a control), 0.2, 0.4 and 0.6 ppm of selenium (Se) by supplementing the diets with seleniferous WCB. The isonitrogenous and isocaloric diets containing 5% non-seleniferous or seleniferous WCB were formulated. Feeding seleniferous WCB did not affect (p<0.05) the feed intake and BW gain. Total blood lipid concentration was significantly (p<0.05) decreased with increasing Se levels. Total blood cholesterol concentration for the control was significantly (p<0.05) higher than that for 0.4 and 0.6 ppm of Se treatments. Increasing the Se levels in WCB significantly (p<0.05) decreased blood triglyceride concentration; however, the levels increased immunoglobulin G and selenium concentrations. Feeding seleniferous WCB did not affect the carcass rate, backfat thickness and meat quality as well as yield grades. The Se concentration in the kidney, liver and loin were significantly (p<0.05) increased with increasing levels of seleniferous WCB. The results indicated that feeding seleniferous WCB may improve the blood characteristics related to lipid metabolism and thus, could produce selenium-fortified pork. Moreover, it is shown that the dietary optimal selenium level to depose selenium in porcine tissues by utilizing seleniferous WCB would be 0.4 mg of Se/kg of ration. Moreover, when 100 g of pork produced from pigs raised under such condition is served to consumers, it meets the minimum recommended daily requirements (40 ${\mu}g$) of dietary selenium proposed by the World Health Organization (1996).

A Suvey on Satisfaction Measurement of Automatic Milking System in Domestic Dairy Farm (자동착유시스템 설치농가의 설치 후 만족도에 관한 실태조사)

  • Ki, Kwang-Seok;Kim, Jong-Hyeong;Jeong, Young-Hun;Kim, Yun-Ho;Park, Sung-Jai;Kim, Sang-Bum;Lee, Wang-Shik;Lee, Hyun-June;Cho, Won-Mo;Baek, Kwang-Soo;Kim, Hyeon-Shup;Kwon, Eung-Gi;Kim, Wan-Young;Jeo, Joon-Mo
    • Journal of Animal Environmental Science
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    • v.17 no.1
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    • pp.39-48
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    • 2011
  • The present survey was conducted to provide basic information on automatic milking system (AMS) in relation to purchase motive, milk yield and quality, customer satisfaction, difficulties of operation and customer suggestions, etc. Purchase motives of AMS were insufficient labor (44%), planning of dairy experience farm (25%), better performance of high yield cows (19%) and others (6%), respectively. Average cow performance after using AMS was 30.9l/d for milk yield, 3.9% for milk fat, 9,100/ml for bacterial counts. Sixty-eight percentage of respondents were very positive in response to AMS use for their successors but 18% were negative. The AMS operators were owner (44%), successor (44%), wife (6%) and company worker (6%), respectively. The most difficulty (31%) in using AMS was operating the system and complicated program manual. The rate of response to system error and breakdown was 25%. The reasons for culling cow after using AMS were mastitis (28%), reproduction failure (19%), incorrect teat placement (12%), metabolic disease (7%) and others (14%), respectively. Fifty-six percentages of the respondents made AMS maintenance contract and 44% did not. Average annual cost of the maintenance contract was 6,580,000 won. Average score for AMS satisfaction measurement (1 to 5 range) was 3.2 with decrease of labor cost 3.7, company A/S 3.6, increase of milk yield 3.2 and decrease of somatic cell count 2.8, respectively. Suggestions for the higher efficiency in using AMS were selecting cows with correct udder shape and teat placement, proper environment, capital and land, and attitude for continuous observation. Systematic consulting was highly required for AMS companies followed by low cost for AMS setup and systematization of A/S.

Effects of Feeding Type of Concentrates During Growing Period and Slaughter Age on Growth Performance, Feed Efficiency and Carcass Characteristics in Growing-Fattening Holstein Steers (홀스타인 거세우에 대한 육성기 농후사료 급여형태 및 출하월령이 성장발육, 사료이용성 및 도체특성에 미치는 효과)

  • Kang, S.W.;Jeong, H.Y.;Ahn, B.S.;Oh, Y.K.;Son, Y.S.
    • Journal of Animal Science and Technology
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    • v.46 no.6
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    • pp.989-998
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    • 2004
  • The objectives of this work was to investigate the effects of feeding type of concentrates during growing period and slaughter age on growth performance, feed efficiency and carcass characteristics in growing-fattening Holstein steers. Treatments were two concentrates feeding types(ad libitum or restricted 1.9% of BW) and three slaughter ages(at 19, 22 or 25 mo). Body weight at slaughter was numerically higher(approx. 8.3%) for the restricted than the ad libitum feeding groups. TDN intake rate was higher(8.4%) for the restricted than the ad libitum feeding groups. One mo slaughter delay increased TDN intake by 4%. Despite the lack of significances, higher back fat thickness and rib-eye area appeared in the restricted feeding or the late slaughter groups compared with the ad libitum feeding or the early slaughter groups. Marbling score(mean 2.46) numerically increased when the steers were restrictively fed concentrates compared with the ad libitum feeding groups. In addition, significant increases in the marbling score were associated with the slaughter age delay. In economic analysis, increases in total income were associated with the restricted feeding and the slaughter age delay. Whereas the highest monthly income appeared in the restricted feeding-and-slaughter at 22 mo group. In conclusion, the optimal feeding system may be 1) the restricted concentrates feeding(1.9% of BW) during growing period and 2) the late slaughter age(22${\sim}$25 mo of age) in growing-fattening Holstein steers fed rice straw.

A Study on the Outlook of Dentists on Dental Coordinators and Their Job (치과의사의 치과 코디네이터 업무 및 인식에 관한 조사연구)

  • Yoo, Jung-Sook;Jang, Mi-Hwa;Jung, Jae-Yeon;Cho, Myung-Sook;Choi, Bu-Geun;Hwang, Yoon-Sook
    • Journal of Korean society of Dental Hygiene
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    • v.5 no.2
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    • pp.201-218
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    • 2005
  • The purpose of this study was to examine how dentists perceived dental coordinators including their education, hiring criteria, working condition and job. It's basically attempted to help define the job and role of 5 and to suggest how they should be nurtured. The subjects in this study were dentists at dental hospitals and clinics where dental coordinators were employed among approximately 200 dental institutions in Seoul, Cyeonggi province and Incheon. After a survey was conducted in June 2005, answer sheets from 99 respondents were analyzed. The findings of the study were as follows: 1. Regarding education for dental coordinators, 99.9% of the dentists investigated felt the need for separate education programs for dental coordinators, 42.4% knew what would-be dental coordinators learned about, and 81.8% considered it necessary for them to take intermediate or higher courses. An organization affiliated with the Korea Dental Hygienists Association was viewed as the best institute to educate dental coordinators, and educational institutes that included a department of dental hygiene was looked upon as the second best one. 68.7% believed that dental coordinators should take an official examination to test their qualifications, and concerning educational subsidy, the largest group of the dentists thought that a certain amount of subsidy should be provided. 2. As for coordinator hiring, the top priority was the impression(look) of applicants(55%), followed by adjustability to existing employees(24.5%) and professional competency(17.3%). As to the route of hiring, 41.4 percent, the largest group, reeducated some of existing employees, and dental hygienists were regarded as the best personnels to serve as a coordinator. Concerning job performance, they put the most emphasis on interpersonal relationship, which was followed by executive ability, impression and career, 58.6% the largest group, believed that dental coordinators should have a three-year or higher career to work at a dental institute. 3. As to working conditions, 75.7%, the largest group, paid dental coordinators based on their job performance, and 23.2%, the second largest group, had their pay equal to that of dental hygienists, 88.9% allowed them to determine their own retirement age. 4. In regard to their perception of dental coordinators, the largest number of the dentists considered it necessary for them to keep receiving education(4.29), and the second largest group felt that they served to enhance the image of dental institutes(4.18). The third largest group thought that they contributed to letting patients more satisfied with the quality of dental services. But they tended not to agree that their turnover rate was low(3.04), and they didn't find them to receive appropriate education, either(3.10). 5. The current major job of coordinators associated with customer services was handling appointments with customers(91.9%), treating unsatisfied customers(85.9%), and controling waiting time(84.8%). Regarding self-management, coordinators directed their energy into having good manners(89.9%), acquiring fundamental dental knowledge(84.8%), and learning how to treat customers(83.8%). Concerning hospital affairs handling, they were most responsible for information desk(87.9%), which was followed by receiving(86.9%). As a result of investigating what type of job the dentists hoped dental coordinators to fulfill in consideration of their career, their age and type of investment, the dentists wanted them the most to speak a foreign language, which belonged to the field of self-management.

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A New Item Recommendation Procedure Using Preference Boundary

  • Kim, Hyea-Kyeong;Jang, Moon-Kyoung;Kim, Jae-Kyeong;Cho, Yoon-Ho
    • Asia pacific journal of information systems
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    • v.20 no.1
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    • pp.81-99
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    • 2010
  • Lately, in consumers' markets the number of new items is rapidly increasing at an overwhelming rate while consumers have limited access to information about those new products in making a sensible, well-informed purchase. Therefore, item providers and customers need a system which recommends right items to right customers. Also, whenever new items are released, for instance, the recommender system specializing in new items can help item providers locate and identify potential customers. Currently, new items are being added to an existing system without being specially noted to consumers, making it difficult for consumers to identify and evaluate new products introduced in the markets. Most of previous approaches for recommender systems have to rely on the usage history of customers. For new items, this content-based (CB) approach is simply not available for the system to recommend those new items to potential consumers. Although collaborative filtering (CF) approach is not directly applicable to solve the new item problem, it would be a good idea to use the basic principle of CF which identifies similar customers, i,e. neighbors, and recommend items to those customers who have liked the similar items in the past. This research aims to suggest a hybrid recommendation procedure based on the preference boundary of target customer. We suggest the hybrid recommendation procedure using the preference boundary in the feature space for recommending new items only. The basic principle is that if a new item belongs within the preference boundary of a target customer, then it is evaluated to be preferred by the customer. Customers' preferences and characteristics of items including new items are represented in a feature space, and the scope or boundary of the target customer's preference is extended to those of neighbors'. The new item recommendation procedure consists of three steps. The first step is analyzing the profile of items, which are represented as k-dimensional feature values. The second step is to determine the representative point of the target customer's preference boundary, the centroid, based on a personal information set. To determine the centroid of preference boundary of a target customer, three algorithms are developed in this research: one is using the centroid of a target customer only (TC), the other is using centroid of a (dummy) big target customer that is composed of a target customer and his/her neighbors (BC), and another is using centroids of a target customer and his/her neighbors (NC). The third step is to determine the range of the preference boundary, the radius. The suggested algorithm Is using the average distance (AD) between the centroid and all purchased items. We test whether the CF-based approach to determine the centroid of the preference boundary improves the recommendation quality or not. For this purpose, we develop two hybrid algorithms, BC and NC, which use neighbors when deciding centroid of the preference boundary. To test the validity of hybrid algorithms, BC and NC, we developed CB-algorithm, TC, which uses target customers only. We measured effectiveness scores of suggested algorithms and compared them through a series of experiments with a set of real mobile image transaction data. We spilt the period between 1st June 2004 and 31st July and the period between 1st August and 31st August 2004 as a training set and a test set, respectively. The training set Is used to make the preference boundary, and the test set is used to evaluate the performance of the suggested hybrid recommendation procedure. The main aim of this research Is to compare the hybrid recommendation algorithm with the CB algorithm. To evaluate the performance of each algorithm, we compare the purchased new item list in test period with the recommended item list which is recommended by suggested algorithms. So we employ the evaluation metric to hit the ratio for evaluating our algorithms. The hit ratio is defined as the ratio of the hit set size to the recommended set size. The hit set size means the number of success of recommendations in our experiment, and the test set size means the number of purchased items during the test period. Experimental test result shows the hit ratio of BC and NC is bigger than that of TC. This means using neighbors Is more effective to recommend new items. That is hybrid algorithm using CF is more effective when recommending to consumers new items than the algorithm using only CB. The reason of the smaller hit ratio of BC than that of NC is that BC is defined as a dummy or virtual customer who purchased all items of target customers' and neighbors'. That is centroid of BC often shifts from that of TC, so it tends to reflect skewed characters of target customer. So the recommendation algorithm using NC shows the best hit ratio, because NC has sufficient information about target customers and their neighbors without damaging the information about the target customers.