• Korean Journal of Agricultural Science
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• v.4 no.1
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• pp.10-20
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• 1977

An expriment was conducted to determine the rate of germination under low temperature and effects of low temperature on seedling of varieties derived from the cross between Indica and Japonica type of rice. Total of 30 varieties including leading variety, Tongil, were germinated at the temperature of $10^{\circ}C$. and $15^{\circ}C$. to determine the rate of germination, and six varieties also including Tongil were planted in pot, and seedlings were exposed to the temperature of $5^{\circ}C$. and $1^{\circ}C$. for 15 days and damage of plant growth due to low temperature was observed. 1. Under the condition of $10^{\circ}C$., varieties such as Iri #323, Suwon #253, Iri #325, Milyang #22, Suwon #251, and Suwon #267 were showing over 70 percent of germination ratio, while varieties, Dodolokiwase, Milyang #23, Yusin, Iri #328, and Iri #329 were below 10 percent in germination ratio. 2. Under the condition of $15^{\circ}C$., variety Suwon #262 was shown 100 percent of germination and varieties such as Milyg an#22, Dodlokiwase, Tongil, Milyang #29, Suwon #258, Milyang #23, Milyang #24, Milyang #28 and Milyang #21 were over 90 percent in germination ratio. However, varieties such as Iri #328, Iri #329, Jinheung, and Minehikari were below 50 percent in germination rate. 3. Considering the germination rate and average days required to germination, Milyang #22 and Iri #323 were highly resistant varieties to low temperature. The rate of germination of varieties from the cross between Indica and Japonica under low temperature was not always lower than that of varieties from Japonica type of rice. 4. Most of the seedlings of varieties used were quite resistant to $1^{\circ}C$. at least for six hours. However, leaves of rice were exposed to the the temperature of $1^{\circ}C$. for 12 hours, and the withered leaves were recovered soon when put in under normal temperature. The degree of leaf withering under low temperature was lower in Milyang #15, Japonica type than in varietieties belonging to $Indica{\times}Japonica$ type of rice. 5. When the seedlings of varieties such as Josaengtongil, Tongil and Yusin were exposed to the temperature of $1^{\circ}C$. for 36 hours, 70 percent of leaves were withered and when the time of expose were doubled, the leaves were completely died. When the temperature was fluctuated, over 75 percent of leaves were died, while 65 percent of leaves of Milyang #15 were died when exposed to $1^{\circ}C$, for 72 hours. 6. Significant growth retardation was observed for all entries when exposed to $1^{\circ}C$. for 24 to 36 hours. The growth retardation was apparently increased as the time of expose was extended.

• Journal of Korea Spatial Information System Society
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• v.6 no.1 s.11
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• pp.73-85
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• 2004

Recently, as the growth of the wireless Internet, PDA and HPC, the focus of research and development related with GIS(Geographic Information System) has been changed to the Real-Time Mobile GIS to service LBS. To offer LBS efficiently, there must be the Real-Time GIS platform that can deal with dynamic status of moving objects and a location index which can deal with the characteristics of location data. Location data can use the same data type(e.g., point) of GIS, but the management of location data is very different. Therefore, in this paper, we studied the Real-Time Mobile GIS using the HBR-tree to manage mass of location data efficiently. The Real-Time Mobile GIS which is developed in this paper consists of the HBR-tree and the Real-Time GIS Platform HBR-tree. we proposed in this paper, is a combined index type of the R-tree and the spatial hash Although location data are updated frequently, update operations are done within the same hash table in the HBR-tree, so it costs less than other tree-based indexes Since the HBR-tree uses the same search mechanism of the R-tree, it is possible to search location data quickly. The Real-Time GIS platform consists of a Real-Time GIS engine that is extended from a main memory database system. a middleware which can transfer spatial, aspatial data to clients and receive location data from clients, and a mobile client which operates on the mobile devices. Especially, this paper described the performance evaluation conducted with practical tests if the HBR-tree and the Real-Time GIS engine respectively.

• Journal of Chest Surgery
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• v.42 no.3
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• pp.283-291
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• 2009

Background: Tracheal reconstruction after extended tracheal resection still remains as a major surgical challenge because good clinical outcomes are usually correlated with limited tracheal resection. Recent investigations with a using cryopreserved trachea for the reconstruction of a trachea have been carried out to overcome this problem. In this study, we analyzed viability of tracheas, which is an important determining factor for the success of transplanting a cryopreserved trachea and the development of post-transplantation tracheal stenosis, according to three different experimental factors: 1) the warm-ischemic time, 2) the cryopreservation solution and 3) the preserving temperature, to determine a better cryopreservation protocol and a better composition of the cryopreservation solution. Material and Method: Rats tracheas were harvested for different warm-ischemic times (0 hr, 12 hrs, 24 hrs). The tracheas were treated with recombinant insulin growth factor-1 (IGF) and they were stored at three different temperatures $(4^{\circ}C,\;-80^{\circ}C,\;-196^{\circ}C)$ for two weeks. After two weeks, we thawed the stored trachea and isolated the cells of the tracheas with using type II collagenase. We cultured the cells for seven days and then we compared the cellular viability by the MTT reduction assay. Result: Though cryopreservation is required to preserve a trachea for a longer time period, the viability of the tracheas stored at $-80^{\circ}C$ and $-196^{\circ}C$ was significantly reduced compared to that of the tracheas stored at $4^{\circ}C$. The viability of the tracheas with warm-ischemic times of 12 hrs and 24 hrs was also reduced in comparison to the tracheas with a warm-ischemic time of 0 hrs. Our data showed that the warm ischemic time and the parameters of crypreservation negatively affect on trachea viability. However, a cryopresrvation solution containing IGF-1 improved the cellular viability better than the existing cryopreservation solution. For the warm ischemic time group of a 0 hr, the addition of IGF-1 improved the viability of trachea at all the preserving temperatures. Conclusion: These experiments demonstrate that the viability of cryopreserved trachea can improved by modifying the components of the crypreservation solution with the addition of IGF-1 and reducing the warm-ischemic time.

• Microbiology and Biotechnology Letters
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• v.33 no.1
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• pp.41-50
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• 2005

An organic acid tolerance mutant (M-200) was obtained from Leuconostoc mesenteroides KCCM 35471, followed by the screening procedure using a specific organic acid medium (lactic acid: acetic acid, 2:1). The characteristics of the acid tolerance M-200 and the wild type LM-W were examined at various temperature and pH ranges $(l0-30^{\circ}C$ of temp, 3.5-4.5 of pH). The growth of strain M-200 at HCl adjusted medium $(10^{\circ}C\;and\;pH 3.5)$ was observed. In the case of organic acid adjusted medium, the strain showed its growth at the pH range of 3.8. When the strain M-200 was used as a starter for Kimchi fermentation, a constant acid level (0.55) was observed during the whole fermentation period. This result indicates that the strain produces a proper level of acid content for the Kimchi fermentation. This result also indicates that the edible period of Kimchi can be extended to 3.5 fold compare to the result obtained from the LM-W used Kimchi fermentation. However the excess use of the strain M-200 showed the inhibition of growth of Lactobacillus plantarum, low lactic acid level content and low level of organoleptic test. In the case of organic acid content during the Kimchi fermentation, the strain M-200 showed relatively low production rate compare to the wild type (M-200: 3.5 mg/L at 21 days of fermentation, LM-W: 7 mg/L at 21 days of fermentation). Therefore a mixed Kimchi starter containing M-200 and other strains probably maintain a good Kimchi quality during the fermentation.

• Microbiology and Biotechnology Letters
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• v.48 no.3
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• pp.344-357
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• 2020

Strain improvement and bioprocess development were undertaken to enhance hyaluronic acid(HA) production by Streptococcus zooepidemicus cells. Using a high-yielding mutant strain, statistical medium optimization was carried out in shake flask cultures, resulting in 52% increase in HA production (5.38 g/l) at the optimal medium composition relative to the parallel control cultures. For sufficient supply of dissolved oxygen (DO), which turned out to be crucial for enhanced production of HA, agitation system and speed were intensively investigated in 5 L bioreactor cultures. Increase in oxygen mass transfer coefficient (k_La) through increment of agitation speed (rpm) and 35% expansion of diameter of the newly-designed impellers showed significantly positive effects on HA production. By installing an expanded Rushton-turbine impeller for efficient break-down of sparged air, and an extended marine impeller above the Rushton-turbine impeller for efficient mixing of the air-born viscous fermentation broth, maximum amount of HA (9.79 g/l) was obtained at 450 rpm, 1.8 times higher level than that of the corresponding flask culture. Subsequently, the possibility of bioprocess scale-up to a 50 L bioreactor was investigated. Despite almost identical maximum HA production (9.11 vs 9.25 g/l), the average HA volumetric productivity (r_p) of the 50 L culture turned out only 74% compared to the corresponding 5 L culture during the exponential phase, possibly caused by shear damages imposed on the producing cells at the high stirring in the 50 L culture. The scale-up process could be successfully achieved if a scale-up criterion of constant oxygen mass transfer coefficient (k_La) is applied to the 50 L pilot-scale bioreactor system.

• Korean Journal of Cleft Lip And Palate
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• v.3 no.1
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• pp.23-31
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• 2000

Objective: When an alveolar cleft is too large to close with adjacent mucobuccal flaps or large secondary fistula following a primary bilateral palatoplasty exists, a one-stage procedure for bone grafting becomes challenging. In such a case, we used the tongue flap to repair the fistula and cleft alveolus in the first stage, and bone grafting to the cleft defect was performed in the second stage several months later. The purpose of this paper is to report our experiences with the use of an anteriorly-based Y-shaped tongue flap to fit the palatal and labial alveolar defects and the ultimate result of the bone graft. Patients: A series of 14 patients underwent surgery of this type from January 1994 to December 1998.The average age of the patients was 15.8 years old (range: 5 to 28 years old). The mean period of follow-up following the 2nd stage bone raft operation was 45.9 months (range: 9 to 68 months). In nine of the 14 cases, the long-fork type of a Yshaped tongue flap was used for extended coverage of the labial side alveolar defects with the palatal fistula in the remaining cases the short-forked design was used. Results: All cases demonstrated a good clinical result after the initial repair of cleft alveolus and palatal fistula. There was no fistula recurrence, although Partial necrosis of distal margin in long-forked tongue flap was occurred in one case. Furthermore, the bone graft, which was performed an average of 8 months after the tongue flap repair, was always successful. Occasionally, the transferred tongue tissue was bulging and interfering with the hygienic care of nearby teeth; however, these problems were able to be solved with proper contour-pasty performed afterwards. No donor site complications such as sensory disturbance, change in taste, limitations in tongue movement, normal speech impairments or tongue disfigurement were encountered. Conclusion: This two-stage reconstruction of a bilateral cleft alveolus using a Y-shaped tongue flap and iliac bone graft was very successful. It may be indicated for a bilateral cleft alveolus patient where the direct closure of the cleft defect with adjacent tissue or the buccal flap is not easy due to scarred fibrotic mucosa and/or accompanied residual palatal fistula.

• Journal of the Korean Society of Food Science and Nutrition
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• v.46 no.1
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• pp.100-107
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• 2017

This study was conducted to evaluate the quality characteristics of got mul-kimchi during storage by type of kimchi container using a plastic ark shell. The pH level, acidity, hardness, color, sensory evaluation, and microbiological activity were performed. Kimchi containers were prepared with 0%, 2%, and 3% plastic ark shell. The pH level of 2% container samples showed no significant difference compared with that of the control, whereas pH levels of 3% container samples were significantly (P<0.05) higher than those of the control and 2% sample. Acidity was not different among treatments up to 4 weeks, whereas acidity of 3% container samples was significantly (P<0.05) lower than those of the control and 2% samples after 8 weeks. Hardness significantly decreased (P<0.05) upon 0, 2, and 3% treatments with increasing storage time, but there was no significant difference among the treatments. Hunter color L values increased in the order of 0, 3, and 2% with increasing storage time. In sensory evaluation of crunchiness, 3% container samples had significantly (P<0.05) higher crunchiness than the control. Total viable cells in the 3% container with got mul-kimchi were significantly (P<0.05) lower than those of other samples at 12 and 16 weeks of fermentation. Numbers of lactic acid bacteria in the 2% and 3% container samples were significantly (P<0.05) lower than those of the control samples after 16 weeks of fermentation. These results show that the plastic ark shell kimchi container extended storage compared with the control.

• Journal of the Korean Home Economics Association
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• v.27 no.2
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• pp.133-148
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• 1989

This study attempts of analyze empirically the living status of the elderly in Korea by finding out the problems of it in the family and by clarifying the influences of the family environmental variables and the values on the adjustment of the aged. To carryout the aim of this study, the causes and the patterns of the problems for the aged had been found out through the review of literature. Based on them the questionnaire was prepared including the questions of the values, family environmental vriables as well as the degree of satisfaction of thier liver and the extent of life interchange. The former variables were taken as independent and the latter were taken as dependent variables, so that the relationship between the two variables could be exemplified. The 400 aged over 60 living in Seoul and the other cities were selected through the purposive sampling and interviewed. The answers of the 376 respondents, 94% of the sample, were analyzed for this study. The following results have been found out through the various statistical analysis such as frequency distribution, chi-square test, pearson's correlation, analysis of variance and cluster analysis. At first, the results from the examination of the frequency distribution regarding the living status of the aged are; I) sixteen percent of the respondents living with their married offspring were receiving economical support, though they pointed out the problems of the extended family are the inconveniences with their children (60%) and simpleness (20%) of their livers. It seems that the aged in Korea are poor and have negative opinion on the relationship with their offspring even if they live in the same house. Secondly, it has been found out that the family environmental variables, especially such as sex, occupation, residence, education, level, living ability and the family type, play and important role not only on the degree of satisfaction of their liver but also on the extent of interchange of their lives. However, the variables such as religion and whether the spouse is alive or not do not play and important role. Thirdly, the reported main reasons of their delightness were healthy life (1.87%), the well-being of their offspring (2.08%), the spouse's long life (3.38%), religious activity (5.05%), the hobby activity (4.31%) and the participation in the social activity (5.05%). While, they mainly concern about the illness (1.98%), offspring (2.00%), econmic difficulties (3.39%), inharmonious home (3.81%) and the despicable treatment (3.81%). The respondents wer classified into two groups, they are dependent and independent, using cluster analysis. Health, social activity, offspiring, religion, couple's long life among the factors which lead them to be delighted were turned out to be statistically signhificant at 0.01 significance level between the two groups. As far as their worrisome matters are concerned, health and economic difficulties were significantly different between the two groups. Fourthly, regarding the life interchange, it has been proved that there is a statistically significant differences betwwen the two groups in the economic and the emotional satisfaction, help for ordinary life, status in the family, subjective and objective relationship with offspring, but not in economic dependency and the activity status. Fifthly, it has been noted that there is a high correlation between the degree of life's satisfaction and the extent of life interchange. On the basis of the results mentioned above, it could be concluded taht; i) The majority of the aged in Korea are not economically active, and thus they live with their married offspring even of they have a negative opinion on the subjective relationship with them. This can be pointed out as the main problem of the aged and thus it needs to be studied further. ii) the environmental variables such as age, sex education level, family type and occuption (which can not be changed by their effrot) turned out to give an important effect on the extent of the life interchange among the aged. iii) The respondents who are identified as independent group have a higher degree of life satisfaction and family status than the group identified as defendent. Thus, it can be inferred that it is possible for them to adjust their life by making an effort to modify themselves. iv) The high correlation between the extent of life interchange and the degree of life satisfaction indicates that the elderly themselves can adjust in order to obtain the higher degree of life satisfaction. Therefore, the following suggestions are derived from this study. First of all, the aged should try to be psychologically independent. Second, they need to control themselves in order to achieve self-assurance. Third, the community have to prepare a program of self-development for the aged. Fourth, the social welfare policy that can solve the problem of illness and poverty of the elderly should be introduced, so that their minimum requirements can be satisfied.

• Clinics in Shoulder and Elbow
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• v.14 no.1
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• pp.20-26
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• 2011

Purpose: The purpose of this study is to investigate the accompanying lesions of humerus greater tuberosity fracture with anterior shoulder dislocation and to analyze its clinical results. Materials and Methods: From May 2005 to November 2008, arthroscopy was performed on a total of 30 selected patients who were diagnosed with humerus greater tuberosity fracture with anterior shoulder dislocation and who were also under the age of 40. The preoperative and postoperative Constant and Rowe scores were compared. Results: There was a total of 21 cases of anteroinferior labral lesions: 2 Bankart lesions, 4 bony Bankart lesions, 4 Perthes lesions, 2 free ALPSA lesions, 3 GLAD lesions and 6 capsular tears. For other lesions, 5 rotator cuff partial tears, 3 SLAP lesions and 1 biceps tendon rupture were found. The constant scores were increased from 56.3 to 94.43 points (p=0.034), and the Rowe scores were increased from 52.56 to 91.76 points (p=0.026). Conclusion: For humerus greater tuberosity fracture with anterior shoulder dislocation, the accompanying lesion was identified and the fracture was treated using arthroscopy. Good clinical results and bone union were achieved. According to the secondary arthroscopic findings, all of the Perthes lesion, the free ALPSA lesion, the GLAD lesion and the capsular tear spontaneously healed or they did not progress to extended rupture although arthroscopic suture was not performed. Any postoperative secondary instability was not observed.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.16 no.12
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• pp.1234-1268
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• 2004

A review on the papers published in the Korean Journal of Air-Conditioning and Refrigerating Engineering in 2002 and 2003 has been carried out. Focus has been put on current status of research in the aspect of heating, cooling, air-conditioning, ventilation, sanitation and building environment/design. The conclusions are as follows. (1) Most of fundamental studies on fluid flow were related with heat transportation in diverse facilities. Drop formation and rivulet flow on solid surfaces were interesting topics related with condensation augmentation. Research on micro environment considering flow, heat transfer, humidity was also interesting to promote comfortable living environment. It can be extended considering biological aspects. Development of fans and blowers of high performance and low noise were continuing research topics. Well developed CFD technologies were widely applied for analysis and design of various facilities and their systems. (2) Heat transfer characteristics of enhanced finned tube heat exchangers and heat sinks were extensively investigated. Experimental studies on the boiling heat transfer, vortex generators, fluidized bed heat exchangers, and frosting and defrosting characteristics were also conducted. In addition, the numerical simulations on various heat exchangers were performed and reported to show heat transfer characteristics and performance of the heat exchanger. (3) A review of the recent studies shows that the performance analysis of heat pump have been made by various simulations and experiments. Progresses have been made specifically on the multi-type heat pump systems and other heat pump systems in which exhaust energy is utilized. The performance characteristics of heat pipe have been studied numerically and experimentally, which proves the validity of the developed simulation programs. The effect of various factors on the heat pipe performance has also been examined. Studies of the ice storage system have been focused on the operational characteristics of the system and on the basics of thermal storage materials. Researches into the phase change have been carried out steadily. Several papers deal with the cycle analysis of a few thermodynamic systems which are very useful in the field of air-conditioning and refrigeration. (4) Recent studies on refrigeration and air-conditioning systems have focused on the system performance and efficiency enhancement when new alternative refrigerants are applied. Heat transfer characteristics during evaporation and condensation are investigated for several tube shapes and new alternative refrigerants including natural refrigerants. Efficiency of various compressors and performance of new expansion devices are also dealt with for better design of refrigeration/air conditioning system. In addition to the studies related with thermophysical properties of refrigerant mixtures, studies on new refrigerants are also carried out. It should be noted that the researches on two-phase flow are constantly carried out. (5) A review of the recent studies on absorption refrigeration system indicates that heat and mass transfer enhancement is the key factor in improving the system performance. Various experiments have been carried out and diverse simulation models have been presented. Study on the small scale absorption refrigeration system draws a new attention. Cooling tower was also the research object in the respect of enhancement its efficiency, and performance analysis and optimization was carried out. (6) Based on a review of recent studies on indoor thermal environment and building service systems, it is noticed that research issues have mainly focused on several innovative systems such as personal environmental modules, air-barrier type perimeterless system with UFAC, radiant floor cooling system, etc. New approaches are highlighted for improving indoor environmental conditions and minimizing energy consumption, various activities of building energy management and cost-benefit analysis for economic evaluation.