• Korean Journal of Environmental Biology
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• v.32 no.4
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• pp.297-305
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• 2014

In order to understand the contribution of seaweed aquaculture to nutrients and carbon cycles in coastal environments, we measured the nutrients & carbon uptake rates of Porphyra yezoensis Ueda sampled at Nakdong-River Estuary using a chamber incubation method from November 2011 to April 2012. It was observed that the production rate of dissolved oxygen by P. yezoensis (n=30~40) was about $68.8{\pm}46.0{\mu}mol\;{g_{FW}}^{-1}h^{-1}$ and uptake rate of nitrate, phosphate and dissolved inorganic carbon (DIC) was found to be $2.5{\pm}1.8{\mu}mol\;{g_{FW}}^{-1}h^{-1}$, $0.18{\pm}0.11{\mu}mol\;{g_{FW}}^{-1}h^{-1}$ and $87.1{\pm}57.3{\mu}mol\;{g_{FW}}^{-1}h^{-1}$, respectively. There was a positive linear correlation existed between the production rate of dissolved oxygen and the consumption rates of nitrate, phosphate and DIC, respectively, suggesting that these factors may serve as good indicators of P. yezoensis photosynthesis. Further, there was a negative logarithmic relationship between fresh weight of thallus and uptake rates of nutrients and $CO_2$, which suggested that younger specimens (0.1~0.3 g) were much more efficient at nutrients and $CO_2$ uptake than old specimens. It means that the early culturing stage than harvesting season might have more possibilities to be developed chlorosis by high rates of nitrogen uptake. However, N & C demanding rates of Busan and Jeollabuk-do, calculated by monthly mass production and culturing area, were much higher than those of Jeollanam-do, the highest harvesting area in Korea. Chlorosis events at Jeollabuk-do recently might have developed by the reason that heavily culture in narrow area and insufficient nutrients in maximum yield season (Dec.~Jan.) due mostly to shortage of land discharge and weak water circulation. The annual DIC uptake by P. yezoensis in Nakdong-River Estuary was estimated about $5.6{\times}10^3\;CO_2$ ton, which was about 0.03% of annual carbon dioxide emission of Busan City. Taken together, we suggest more research would be helpful to gain deep insight to evaluate the roles of seaweed aquaculture to the coastal nutrients cycles and global carbon cycle.

• Radiation Oncology Journal
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• v.18 no.1
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• pp.17-25
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• 2000

Purpose : To evaluate the side effects, pattern of failure, and survival rate according to the sequence of postoperative adjuvant radiotherapy and chemotherapy, patients with stages II and III rectal cancer who had undergone curative resection were randomized to 'early radiotherapy group (arm I)' or' late radiotherapy group (arm II)', then we intend to determine the most effective sequence of the radiotherapy and chemotherapy. Materials and Methods . From January 1996 to March 1999, 313 patients with curatively resected stages II and III rectal cancer have been randomized to' early' or' late' radiation therapy group and received combined chemotherapy (5-FU 375 mg/m$^{2}$/day, ieucovorin 20 mg/m$^{2}$, IV bolus daily Dl-5, 8 cycles) and radiation therapy (whole pelvis with 45 Gy/25 fractions/s weeks). Arm I received radiation therapy from day 1 with first cycle of chemotherapy and arm II received radiation therapy from day 57 with third cycle of chemotherapy after completion of first two cycles. Preliminary analysis was peformed with 228 patients registered up to Jun 1998. Two out of the 228 patients were excluded because of double primary cancer. Median follow-up period was 23 months. Results :Local recurrence occurred in 11 patients (9.7$\%$) for arm I and 9 patients (8$\%$) for arm 11. There was no significant difference between both groups ( p=0.64). However, distant metastasis was found in 22 patients (19.5$\%$) for arm I and 35 patients (31.0$\%$) for arm II and which showed statistically significant difference between the two groups ( p=0.046). And neither 3-year disease-free survival (70.2$\%$ vs 59.2$\%$, p=0.2) nor overall survival (89.4$\%$ vs 88.0$\%$, p=0.47) showed significant differences. The incidence of leukopenia during radiation therapy and chemotherapy was 78.3$\%$ and 79.9$\%$ respectively but leukopenia more than RTOG grade 3 was only 2.1$\%$ and 6.0$\%$ respectively. The incidence of diarrhea more than 10 times per day was significantly higher in the patients for arm I than for arm II (71.2$\%$ vs 41.6$\%$, p=0.02) but this complication was controlled with supportive cares. Conclusion : Regardless of the sequence of postoperative adjuvant radiation therapy and chemotherapy after curative resection for rectal cancer, local recurrence rate was low with combined chemoradlotherapy. But distant metastasis rate was lower in early radiation therapy group than in late radiation therapy group and the reason is unclear. Most patients completed these treatments without severe complication, so these were thought to be safe treatments but the treatment compliance should be improved.

• Journal of The Korean Society of Grassland and Forage Science
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• v.22 no.3
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• pp.153-160
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• 2002

To investigate the effects of the exogenous N $O_3$$^{[-10]}$ supply level on the nitrate assimilation and growth during the vegetative growth stage, and on the accumulation of organic reserves during the successive regrowth period, dry matter (DM), the amount of nitrogenous compounds, total N and starch in alfalfa plants grown hydroponically with 0.2, 1.0 and 3.0 mM KN $O_3$ was estimated, respectively, during vegetative growth period and two cycle of regrowth. When compared with DMs and N contents in various N compounds in the organs grown with 1.0 mM N $O_3$$^{[-10]}$ , N starvation symptoms were found in 0.2 mM and a depressive effect was observed in 3.0 mM after 10 weeks of vegetative growth. Total starch content in root system gown with 0.2, 1.0 and 3.0 mM N $O_3$$^{[-10]}$ during the first regrowth was 50.96, 15.47 and 6.37 mg plant$^{-1}$, respectively. Starch was contained mainly in taproots. The starch content was not significantly changed by 24 days of the second regrowth with 1.0 mM N $H_4$N0$_3$. Total nitrogen content in root system grown with 0.2, 1.0 and 3.0 mM N $O_3$$^{[-10]}$ during the first regrowth was 6.66, 8.43 and 11.09 mg plant$^{-1}$ , respectively. Nitrogen was contained mainly in lateral roots; 80% (in 0.2 mM), 74% (1.0 mM) and 76% (3.0 mM) of total nitrogen in root system. Total N content in root system at the end of the second regrowth also closely affected by the N $O_3$$^{[-10]}$ supply level during the first regrowth. These results suggest that the level of N $O_3$$^{[-10]}$ may strongly influence the accumulation of organic reserves in root system, and that the initial level of organic reserves for the successive regrowth was one of the determinants for shoot regrowth.

• Korean Journal of Soil Science and Fertilizer
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• v.44 no.6
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• pp.1245-1251
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• 2011

As a result of the growing livestock industry, varieties of organic solid and waste biomass are be generated in swine breeding and slaughtering stages. Anaerobic digestion is a promising alternative for the treatment of livestock waste biomass, as well as for the material recovery and energy production. Objectives of this study were to analyze the biochemical methane potential of swine waste biomasses that were generated from swine pen and slaughterhouse and to investigate the material recovery and methane yield per head. As pig waste biomass, swine slurry, blood, intestine residue, and digestive tract content were collected for investigation from pig farmhouse and slaughterhouse. The $B_{th}$ (Theoretical methane potential) and $B_0$ (Biochemical methane potential) of swine slurry generating in swine breeding stage were 0.525 and $0.360Nm^3\;kg^{-1}-VS_{added}$, the ratio of degradation ($B_0/B_{th}$) was 68.6%. $B_{th}$ of blood, intestine residue, and digestive tract content were 0.539, 0.664, and $0.517Nm^3\;kg^{-1}-VS_{added}$, and $B_0$ were 0.405, 0.213, and $0.240Nm^3\;kg^{-1}-VS_{added}$, respectively. And the ratio of degradation showed 75.1, 32.1, and 46.4% in blood, intestine residue, and digestive tract content. Material yield of swine waste biomass was calculated as TS 73.79, VS 46.75, TN 5.58, $P_2O_5$ 1.94, and $K_2O$ $2.91kg\;head^{-1}$. And methane yield was $16.58Nm^3\;head^{-1}$. In the aspect that slaughterhouse is a large point source of waste biomass, while swine farmhouse is non-point source, the feasibility of an anaerobic digestion using the slaughtering waste biomass need to be assessed in the economical aspect between the waste treatment cost and the profitable effect by methane production.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.29 no.6
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• pp.327-340
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• 2017

This article reviews the papers published in the Korean Journal of Air-Conditioning and Refrigeration Engineering during 2016. It is intended to understand the status of current research in the areas of heating, cooling, ventilation, sanitation, and indoor environments of buildings and plant facilities. Conclusions are as follows. (1) The research works on the thermal and fluid engineering have been reviewed as groups of flow, heat and mass transfer, the reduction of pollutant exhaust gas, cooling and heating, the renewable energy system and the flow around buildings. CFD schemes were used more for all research areas. (2) Research works on heat transfer area have been reviewed in the categories of heat transfer characteristics, pool boiling and condensing heat transfer and industrial heat exchangers. Researches on heat transfer characteristics included the results of the long-term performance variation of the plate-type enthalpy exchange element made of paper, design optimization of an extruded-type cooling structure for reducing the weight of LED street lights, and hot plate welding of thermoplastic elastomer packing. In the area of pool boiling and condensing, the heat transfer characteristics of a finned-tube heat exchanger in a PCM (phase change material) thermal energy storage system, influence of flow boiling heat transfer on fouling phenomenon in nanofluids, and PCM at the simultaneous charging and discharging condition were studied. In the area of industrial heat exchangers, one-dimensional flow network model and porous-media model, and R245fa in a plate-shell heat exchanger were studied. (3) Various studies were published in the categories of refrigeration cycle, alternative refrigeration/energy system, system control. In the refrigeration cycle category, subjects include mobile cold storage heat exchanger, compressor reliability, indirect refrigeration system with $CO_2$ as secondary fluid, heat pump for fuel-cell vehicle, heat recovery from hybrid drier and heat exchangers with two-port and flat tubes. In the alternative refrigeration/energy system category, subjects include membrane module for dehumidification refrigeration, desiccant-assisted low-temperature drying, regenerative evaporative cooler and ejector-assisted multi-stage evaporation. In the system control category, subjects include multi-refrigeration system control, emergency cooling of data center and variable-speed compressor control. (4) In building mechanical system research fields, fifteenth studies were reported for achieving effective design of the mechanical systems, and also for maximizing the energy efficiency of buildings. The topics of the studies included energy performance, HVAC system, ventilation, renewable energies, etc. Proposed designs, performance tests using numerical methods and experiments provide useful information and key data which could be help for improving the energy efficiency of the buildings. (5) The field of architectural environment was mostly focused on indoor environment and building energy. The main researches of indoor environment were related to the analyses of indoor thermal environments controlled by portable cooler, the effects of outdoor wind pressure in airflow at high-rise buildings, window air tightness related to the filling piece shapes, stack effect in core type's office building and the development of a movable drawer-type light shelf with adjustable depth of the reflector. The subjects of building energy were worked on the energy consumption analysis in office building, the prediction of exit air temperature of horizontal geothermal heat exchanger, LS-SVM based modeling of hot water supply load for district heating system, the energy saving effect of ERV system using night purge control method and the effect of strengthened insulation level to the building heating and cooling load.

• Korean Chemical Engineering Research
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• v.59 no.3
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• pp.345-358
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• 2021

This study focuses on the development of the liquid air production process that uses LNG (liquefied natural gas) cold energy which usually wasted during the regasification stage. The liquid air can be transported to the LNG exporter, and it can be utilized as the cold source to replace certain amount of refrigerant for the natural gas liquefaction. Therefore, the condition of the liquid air has to satisfy the available pressure of LNG storage tank. To satisfy pressure constraint of the membrane type LNG tank, proposed process is designed to produce liquid air at 1.3bar. In proposed process, the air is precooled by heat exchange with LNG and subcooled by nitrogen refrigeration cycle. When the amount of transported liquid air is as large as the capacity of the LNG carrier, it could be economical in terms of the transportation cost. In addition, larger liquid air can give more cold energy that can be used in natural gas liquefaction plant. To analyze the effect of the liquid air production amount, under the same LNG supply condition, the proposed process is simulated under 3 different air flow rate: 0.50 kg/s, 0.75 kg/s, 1.00 kg/s, correspond to Case1, Case2, and Case3, respectively. Each case was analyzed thermodynamically and economically. It shows a tendency that the more liquid air production, the more energy demanded per same mass of product as Case3 is 0.18kWh higher than Base case. In consequence the production cost per 1 kg liquid air in Case3 was $0.0172 higher. However, as liquid air production increases, the transportation cost per 1 kg liquid air has reduced by $0.0395. In terms of overall cost, Case 3 confirmed that liquid air can be produced and transported with $0.0223 less per kilogram than Base case.

• Radiation Oncology Journal
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• v.16 no.1
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• pp.7-16
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• 1998

Purpose : To evaluate survival rate and prognostic factors affecting survival of patients with esophageal cancer treated with concurrent chemoradiation. Materials and Methods : Eligibility included biopsy proven invasive carcinoma of the cervical or thoracic esophagus, confined to esophagus and mediastinum with or without regional lymph node and supraclavicular lymph node, and ECOG Performance status $H_0-H_2$. Patients received radiation therapy with 5940cGy over 7 weeks and chemotherapy, consisted of 5-FU(1000 $mg/m^2/day$ in continuous infusion for 5 days, days 1 to 5 and days 29 to 33) and mitomycin C($8mg/m^2$ intravenous bolus at day 1). After concurrent chemoradiation, maintenance chemotherapy was followed with 5-FU(1000 $mg/m^2/day$ in continuous infusion for 5 days at 9th, 13th, and 17th weeks) and cisplatin($80mg/m^2$ intravenous bolus at the first day of each cycle). Results : From November 1989 to November 1995, 44 patients were entered in this study. After treatment, complete response rate and partial response rate were $59\%$ and $41\%$. Overall 1, 2, and 5-year survivals were $59\%$, $38\%$, and $9.6\%$(median 17 months), Prognostic factors affecting survival were response to treatment and T-stage. Among 26 complete responders, there were 6 local recurrences, 3 distant recurrences, 1 local and distant recurrence, and 2 unknown site recurrences Acute and chronic complication rates with grade 3 or more were $20\%$ and $13.0\%$ and there was no treatment-related mortality. Conclusion : Concurrent chemoradiation, compared with historical control groups that treated with radiation alone, improved median survival and did not significantly increase treatment-related complications. Complete responders had longer survival duration than partial responders. Predominant failure pattern was local failure. So, efforts to improve local control should be proposed.

• Journal of Distribution Science
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• v.9 no.1
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• pp.29-38
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• 2011

Since a distribution market was opened in 1993 after the conclusion of the Uruguay Round (UR), various new businesses emerged in the Korean retail industry, such as convenience shops, supermarkets, specialty stores, non-store marketing methods, and cyber shopping malls, in addition to traditional markets and department stores. Competition among these retail businesses has intensified. According to the National Statistical Office (NSO), the growth rate of the total retail industry has shown a 32% increase in the past 5 years. While department stores, supermarkets, specialty stores, and other non-store retailing venues have shown signs of stagnation at a growth rate of 20-30%, which is similar to the growth rate of the entire retail industry, convenience shops and non-store marketing have shown 60-70% growth over the same period. By comparison, the growth rate of cyber shopping malls has nearly tripled. When applying development aspects of retail businesses through the competition to the retail life cycle, mom-and-pop stores and traditional markets have already entered the decline phase as specialty stores reach their maturity phase and demonstrate their limit of growth. Department stores are now in the latter part of the growth phase, which is still considered to have some growth potential. Big super markets are still in the early part of their growth stage although they were introduced 20 years ago. Meanwhile, retail businesses such as convenience stores, supermarkets, mail order houses, and warehouse stores are entering the middle growth phase and are expected to continue with their quantitative growth. At a time when most retail businesses in Korea are in a state of development or in the full growth stage, what kind of new innovative retailing will appear and develop? Moreover, what growth engine will drive it? This study analyzes the appearance of innovative retailing and its development process by establishing a discussable consumer's choice model through the interlocking mutual behavior of differentiated competitiveness and consumers' choice based on an awareness of this issue. The analysis of the results of this study can be summarized as follows. First, if a new vacuum zone emerges at the retail market level, innovative retailing such as low price/low service or high price/high service will emerge simultaneously. Second, if the number of new businesses in the vacuum zone increases, this will create competitiveness among the businesses, and each retailer will develop raising of level. Third, if a new business that raises the level develops, competition between the new and the existing retailer will occur, and an assimilation process between the existing retailing and the new retailing will be unfolded. Fourth, each retailing will promote distribution innovations in order to break the frontier of the existing distribution technology, and other retailing will follow the innovator. On the basis of an analysis of the abovementioned results, this study presents the following three suggestions. First, responding to the consumer's decision-making process on the attributes of retail shops that promote differentiation in strategies, this study established a consumer's choice model that can be discussed in relation to changes in market share. Second, this study provided an analysis of the emerging and developmental processes of innovative retail businesses using a more precise logical structure on the basis of the consumer's choice model described in this study. Third, the development process of retail businesses discussed in this study presented retailing solutions regarding management aspects on how to compose a strong retail mix that can help retail businesses gain competitive advantages in the market.

• Asia Marketing Journal
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• v.13 no.4
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• pp.227-251
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• 2012

This study analyzed Woori Investment and Securities' industry-leading marketing from both a brand management and a marketing decision-making perspective. By executing a different marketing strategy from its competitors, Woori Investment and Securities recognized recent changes in the asset management and investment markets as an open opportunity, and quickly responded to the market changes. First, the company launched the octo brand as a multi-account product, two years before its competitors offered their own products. In particular, it created a differentiated brand image, using the blue octopus character, which became familiar to the general financial community, and was consistently employed as part of an integrated marketing communications strategy. Second, it executed a brand expansion strategy by sub-branding octo in a variety of new financial products, responding to rapid changes in the domestic financial and asset management markets. Through this strategic evolution, the octo brand became a successful wealth management brand and representative of Woori Investment & Securities. Third, it has converged market research, demand and trend analysis, and customer needs acquired through various customer contact channels into a marketing perspective. Thus, marketing has participated in the product development stage, a rarity in the finance industry. Woori Investment and Securities has a leading marketing system. The heart of the successful product creation lies in a collaboration of their customer bases among the finance companies in the Woori Financial Group. The present study suggested a corresponding strategy for octo brand, which is expected to enter into the maturity stage of its product life cycle. In addition, this study found a need to modify the current positioning strategy in order to position and preserve sustainability in the increasingly competitive asset management market. It also suggested the need for an offensive strategy to counter the number one M/S company, and address the issue of cannibalism in the Woori Financial Group.

• Tuberculosis and Respiratory Diseases
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• v.46 no.1
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• pp.36-43
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• 1999

Background : Tumor growth is the net result of intrinsic proliferation and escape from active cell death. bcl-2 is a member of a new category of oncogenes that is not involved in influencing cell proliferation but is involved in regulating cell death(apoptosis). Based on this information, it seems to be reasonable to expect that there may be clinical prognostic significance of bcl-2 expression in non-small cell lung cancer. But its prognostic significance is not established. Methods: To investigate the role of bcl-2 in lung cancer, we performed immunohistochemical stain of bcl-2 on 57 biopsy specimens from resected primary non-small cell lung cancer. Thereafter, flow cytometric cell cycle analysis was done. And we analyzed the correlation between bcl-2 expression, clinical parameters, S-, $G_1$-phase fraction and survival. Results: bcl-2 were detected in 43.8% of total 57 patients(according to histology, squamous cancer 47%, adenocarcinoma 32%, according to TNM stage, I 28.6%, II 52.3%, III 45.5%. both differences were insignificant). By using the flow cytometric analysis, mean S-phase fraction of bcl-2(+) and (-) group were 14.1($\pm7.8$)%, 24.7($\pm10.5$)% (p<0.005), mean $G_1$-phase fraction of bcl-2(+) and bcl-2(-) group were 75.5($\pm10.8$)%, 65.5($\pm11.4$)%(p<0.05). 2yr, 3yr and 5yr survival and median survival time of bcl-2(+) group were 65%, 54%, 41%, 53 months, and those of bcl-2(-) group were 71%, 52%, 46%, 37 months. (p>0.05, Kaplan-Meier, log rank) Conclusion: bcl-2 was detected in 43.8% of primary non-small cell lung cancer. The S-phase fraction of bcl-2(+) group was less than bcl-2(-) group, and G1-phase fraction of bcl-2(+) group was more than bcl-2(-) group. But, expression of bcl-2 could not be a prognostic factor.