• Journal of the Korea Organic Resources Recycling Association
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• v.30 no.4
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• pp.5-13
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• 2022

The current environmental problem is that environmental pollution is accelerating due to the generation of large amounts of waste and indiscriminate consumption of energy. Fossil fuels, a representative energy production fuel, are burned in the process of producing energy, generating a large amount of greenhouse gases and eventually causing climate change. In addition, the amount of waste generated worldwide is continuously increasing, and environmental pollution is occurring in the process of waste treatment. One of the methods for simultaneously solving these problems is the energy recovery from and reduction of organic wastes. Sewage sludge generated in sewage treatment plants has been treated in various ways since ocean disposal was completely prohibited, but the amount generated has been continuously increasing. Since the sewage sludge contains a large amount of organic materials, it is desirable to recover energy from the sewage sludge and reduce the final discharged waste through anaerobic digestion. However, most of the excess sludge is a mass of microorganisms used in sewage treatment, and in order for the excess sludge to be anaerobically digested, the cell walls of the microorganisms must be destroyed first, but it takes a lot of time to destroy the cell walls, so high rates of biogas production and waste reduction cannot be achieved only by anaerobic digestion. Therefore, the pre-treatment process of solubilizing excess sludge is required, and the thermal solubilization process is verified to be the most efficient among various solubilization methods, and high rates of biogas production and waste reduction can be achieved by anaerobic digestion after destroying cell walls the thermal solubilization process. In this study, when pretreating TS 10% thickened excess sludge through a thermal solubilization system, a study was conducted on solubilization characteristics according to retention time and operating temperature variables. The experimental variables for the retention time of the thermal solubilization system were 30 minutes, 60 minutes, 90 minutes, and 120 minutes, respectively, while the operating temperature was fixed at 160℃. The soulbilization rates calculated through TCOD and SCOD derived from the experimental results increased in the order of 12.11%, 20.52%, 28.62%, and 31.40%, respectively. And the variables according to operating temperature were 120℃, 140℃, 160℃, 180℃, and 200℃, respectively, while the operating retention time was fixed at 60 minutes. And the solubilization rates increased in the order of 7.14%, 14.52%, 20.52%, 40.72%, and 57.85%, respectively. In addition, TS, VS, T-N, T-P, NH₄⁺-N, and VFAs were analyzed to evaluate thermal solubilization characteristics of thickened excess sludge. As a result, in order to obtain 30% or more solubilization rate through thermal solubilization of TS 10% thickened excess sludge, 120 minutes of retention time is required when the operating temperature is fixed to 160℃, and 170℃ or more of operating temperature is needed when the operating time is fixed to 60 minutes.

• The Korean Society of Law and Medicine
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• v.22 no.3
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• pp.57-95
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• 2021

Korea's period for preservation of embryos is up to five years (the Bioethics Act). However, the study reviewed domestic and foreign laws and drew issues due to the recent demand that the development of related science and technology and the period limitation limit the rights of consent holder for embryo production. the first issue is that preserved embryos are intended for pregnancy, and it is important to ensure that the autonomy of the consent holder is protected through careful consideration based on information such as scientific evidence. the second is that regulations regarding the obligation to manage embryonic preservation institutions are needed. the third is to create a social atmosphere in which embryo creation, preservation, and disposal take place in a minimum range, considering the special status of embryos. based on this issue, the first of the proposals for rational improvement of the regulation and system about embryo preservation is the introduction of an environment in which sufficient explanation and appropriate consent can be exercised and to extend the reasons for the extension of the period, rather than specifying the specific period in law. the second is that institutionalization is necessary considering not only the obligation to manage preservation institutions but also the overall site, such as concerns that may arise as a result. lastly, we propose the introduction of a management method considering the future use of embryos, such as transfer to provide research purposes and donation of pregnancy purposes by others. this process should be a method of sufficient social discussion and consensus, as well as a general consideration of the family relationship with the born child.

• Tunnel and Underground Space
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• v.34 no.4
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• pp.393-412
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• 2024

In selecting a disposal site for high-level radioactive waste, the hydrogeological research of the site is very important, and the hydraulic conductivity and the storage coefficient are key parameters. In this study, the hydraulic conductivity obtained by two different types of field hydraulic test equipment and methods was compared and analyzed for the deep granite rockmass in the Wonju area to understand the hydraulic characteristics of the deep granite rockmass. One was to perform the lugeon test, constant pressure injection test, and slug test at a maximum depth of 602.0 m by using the auto pressure/flow injection system, and the calculated hydraulic conductivity ranged from 1.26E-9 to 4.16E-8 m/s. In the overall depth, the maximum and minimum differences of the hydraulic conductivity were found to be about 33 times, and in the same test section, the difference by test method or analysis method was 1.13 to 8.25 times. In the other, the hydraulic conductivity calculated by performing a constant pressure injection test and a pulse test at a maximum depth of 705.1 m using the deep borehole hydraulic testing system was found to be 1.60E-10 to 2.05E-8 m/s, and the maximum and minimum differences were found to be about 130 times. In the constant pressure injection test, the difference depending on the analysis method was found to be 1.02 to 2.8 times. The hydraulic conductivity calculated by the two test equipment and methods generally showed similar ranges as E-9 and E-8 m/s, and no clear trend was observed according to depth. It was found that the granite rockmass in the Wonju area where the field hydraulic test was conducted showed low or very low rockmass permeability, and although there are differences in the range of hydraulic conductivity and the depth of application that can be measured depending on the applied test equipment and test method, it is generally believed that reliable results were presented.

• Journal of Intelligence and Information Systems
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• v.27 no.2
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• pp.33-54
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• 2021

With the fourth industrial revolution and the arrival of the New Normal era due to Corona, the importance of Non-contact technologies such as artificial intelligence and big data research has been increasing. Convergent research is being conducted in earnest to keep up with these research trends, but not many studies have been conducted in the area of nuclear research using artificial intelligence and big data-related technologies such as natural language processing and text mining analysis. This study was conducted to confirm the applicability of data science analysis techniques to the field of nuclear research. Furthermore, the study of identifying trends in nuclear spent fuel recognition is critical in terms of being able to determine directions to nuclear industry policies and respond in advance to changes in industrial policies. For those reasons, this study conducted a media trend analysis of pyroprocessing, a spent nuclear fuel treatment technology. We objectively analyze changes in media perception of spent nuclear fuel dry treatment techniques by applying text mining analysis techniques. Text data specializing in Naver's web news articles, including the keywords "Pyroprocessing" and "Sodium Cooled Reactor," were collected through Python code to identify changes in perception over time. The analysis period was set from 2007 to 2020, when the first article was published, and detailed and multi-layered analysis of text data was carried out through analysis methods such as word cloud writing based on frequency analysis, TF-IDF and degree centrality calculation. Analysis of the frequency of the keyword showed that there was a change in media perception of spent nuclear fuel dry treatment technology in the mid-2010s, which was influenced by the Gyeongju earthquake in 2016 and the implementation of the new government's energy conversion policy in 2017. Therefore, trend analysis was conducted based on the corresponding time period, and word frequency analysis, TF-IDF, degree centrality values, and semantic network graphs were derived. Studies show that before the 2010s, media perception of spent nuclear fuel dry treatment technology was diplomatic and positive. However, over time, the frequency of keywords such as "safety", "reexamination", "disposal", and "disassembly" has increased, indicating that the sustainability of spent nuclear fuel dry treatment technology is being seriously considered. It was confirmed that social awareness also changed as spent nuclear fuel dry treatment technology, which was recognized as a political and diplomatic technology, became ambiguous due to changes in domestic policy. This means that domestic policy changes such as nuclear power policy have a greater impact on media perceptions than issues of "spent nuclear fuel processing technology" itself. This seems to be because nuclear policy is a socially more discussed and public-friendly topic than spent nuclear fuel. Therefore, in order to improve social awareness of spent nuclear fuel processing technology, it would be necessary to provide sufficient information about this, and linking it to nuclear policy issues would also be a good idea. In addition, the study highlighted the importance of social science research in nuclear power. It is necessary to apply the social sciences sector widely to the nuclear engineering sector, and considering national policy changes, we could confirm that the nuclear industry would be sustainable. However, this study has limitations that it has applied big data analysis methods only to detailed research areas such as "Pyroprocessing," a spent nuclear fuel dry processing technology. Furthermore, there was no clear basis for the cause of the change in social perception, and only news articles were analyzed to determine social perception. Considering future comments, it is expected that more reliable results will be produced and efficiently used in the field of nuclear policy research if a media trend analysis study on nuclear power is conducted. Recently, the development of uncontact-related technologies such as artificial intelligence and big data research is accelerating in the wake of the recent arrival of the New Normal era caused by corona. Convergence research is being conducted in earnest in various research fields to follow these research trends, but not many studies have been conducted in the nuclear field with artificial intelligence and big data-related technologies such as natural language processing and text mining analysis. The academic significance of this study is that it was possible to confirm the applicability of data science analysis technology in the field of nuclear research. Furthermore, due to the impact of current government energy policies such as nuclear power plant reductions, re-evaluation of spent fuel treatment technology research is undertaken, and key keyword analysis in the field can contribute to future research orientation. It is important to consider the views of others outside, not just the safety technology and engineering integrity of nuclear power, and further reconsider whether it is appropriate to discuss nuclear engineering technology internally. In addition, if multidisciplinary research on nuclear power is carried out, reasonable alternatives can be prepared to maintain the nuclear industry.

• Journal of the Korea Organic Resources Recycling Association
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• v.16 no.2
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• pp.47-56
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• 2008

The objective of this research is to evaluate the optimum recycling methods for the sewage sludge cakes at different microwave power-settings and for different periods of time. The dehydrated sewage sludge cakes used in this study was obtained from N wastewater treatment plan in the P City. The beginning drying processes were carried out in a microwave oven with 2,450 MHz frequency and power ranges of 1kW to 4 kW. The continuous conveyer drying system was also operated with 2,450 MHz frequency and power setting, ranging from of 1 kW to 6 kW. Initial moisture content of the sewage cake is 78~80%, and the moisture content decreased rapidly up to 0.2~2(wt%) within short periods due to breaking the cell walls. This study is also conducted to evaluate the characteristics of sewage sludge cakes with respect to important physical parameters effect on the thermal kinetics for evaporation water in the sludge which are operation times, moisture contents, drying rates, input amounts, flow rates and calorific values. It takes 60 minutes and 120 minutes to reach the critical moisture contents with power setting of 4 kW for 3kg/min and 6kg/min of the flow rates respectively. It takes 120 minutes and 110 minutes to reach the critical moisture contents with flow rates of 2.5 cm/min and sludge input of 6kg/min for the power settings of 4 kW and 6 kW respectively. The most effective value of the power for drying the sludge is 4 kW. Operation with 6kg/min and 4kW on 2cm of the sludge thickness can be effectively and inexpensively to reach the critical moisture contents, when you compare 2cm of the sludge thickness with 1cm and 3cm of the sludge thickness.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.4 no.4
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• pp.113-125
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• 1984

Water supply has been mainly dependent on the construction of the dams in Korea. It is difficult, however, to continue to construct dams for many reasons, such as the decrease of construction sites, the increase of construction costs, the compensation of residents in flooded areas, and the environmental effects. Water demands have increased and are expected to continue increasing due to the concentration of people in the cities, the rise of the living standard, and rapid industrial growth. It is acutely important to find countermeasures such as development of ground water, desalination, and recycling of waste water to cope with increasing water demands. Recycling waste water includes all means of supplying non-potable water for their respective usages with proper water quality which is not the same quality as potable water. The usages of the recycled water include toilet flushing, air conditioning, car washing, yard watering, road cleaning, park sprinkling, and fire fighting, etc. Raw water for recycling is obtained from drainage water from buildings, toilets, and cooling towers, treated waste water, polluted rivers, ground water, reinfall, etc. The water quantity must be considered as well as its quality in selecting raw water for the recycling. The types of recycling may be classified roughly into closed recycle systems and open recycle systems, which can be further subdivided into individual recycle systems, regional recycle systems and large scale recycle system. The treatment methods of wastewater combine biochemical and physiochemical methods. The former includes activated sludge treatment, bio-disc treatment, and contact aeration treatment, and the latter contains sedimentation, sand filtration, activated carbon adsorption, ozone treatment, chlorination, and membrane filter. The recycling patterns in other countries were investigated and the effects of the recycling were divided into direct and indirect effects. The problems of water reuse in recycle patterns were also studied. The problems include technological, sanitary, and operational problems as well as cost and legislative ones. The duties of installation and administrative organization, structural standards for reuse of water, maintenance and financial disposal were also studied.

• Journal of the Mineralogical Society of Korea
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• v.7 no.1
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• pp.49-61
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• 1994

As the groundwater flows along the fractures of crystalline rocks, it will be in contact with the fracture walls mostly coated by secondary minerals which are quite different form those of host rocks. The presence of fracture-filling minerals in crystalline rocks is important on the view point of radioactive waste disposal because of their great surface reactivity. The Surichi drill hole of 200 m in depth in the Yugu area composed mainly of Precambrian gneiss was selected to study the formation process of clay minerals on the fracture wall of gneiss, and their relation with present groundwater. The water-rock interaction in fractures resulted in the formation of gibbsite and clay minerals. They are formed by two different processes : (1) Incongruent dissolution of feldspar by groundwater diffused from a fracture path into rock matrix produced smectite and illite in situ, (2) on the wall of fracture, gibbsite, kaolinite, smectite and illite are formed by precipitation of dissolved species in groundwater. They show the paragenetic sequence such as gibbsite${\leftrightarrow}$kaolinite${\leftrightarrow}$smectite or illite. The paragenetic sequence of fracture-filling minerals was controlled by increase of pH of groundwater, decrease of fracture permeability by precipitation of fillings, and immobility of alkali or alkaline earths in groundwater. The groundwater from the Surichi borehole is a $Na-HCO_{3}$ type with pH range of 8.6-9.2. The sodium and bicarbonate in groundwater would be supplied by the dissolution of albite and calcite, respectively. The saturation index of groundwater and surface water calculated by WATEQ4F indicates that gibbsite and kaolinite are under precipitation to equilibrium state, and that smectite and illite are under equilibrium to redissolution environment. The stability relation of clay minerals in the $Na_{2}O-Al_{2}O_{3}-SiO_{2}-H_{2}O$ system shows that kaolinite is stable for all waters.

• THE INTERNATIONAL COMMERCE & LAW REVIEW
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• v.49
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• pp.283-324
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• 2011

The purpose of this paper is to research the air waybill and the carrier's liability in respect of the carriage of cargo by air under the Montreal Convention of 1999. The Warsaw Convention for the unification of certain rules for international carriage by air was adopted in 1929 and modified successively in 1955, 1961, 1971, 1975 and 1999. The Montreal Convention of 1999 modernized and consolidated the Warsaw Convention and related instruments. Under the Montreal Convention, in respect of the carriage of cargo, the air waybill shall be made out by the consignor. If, at the request of the consignor, the carrier makes it out, the carrier shall be deemed to have done so on behalf of the consignor. The air waybill shall be made out in three orignal parts. Under the Montreal Convention, the consignor shall indemnify the carrier against all damages suffered by the carrier or any other person to whom the carrier is liable, by reason of the irregularity, incorrectness or incompleteness of the particulars and statement furnished by the consignor or on its behalf. The air waybill is not a document of title or negotiable instrument. Under the Montreal Convention, the air waybill is prima facie evidence of the conclusion of the contract, of the acceptance of the cargo and of the conditions of carriage. If the carrier carries out the instructions of the consignor for the disposition of the cargo without requiring the production of the part of the air waybill, the carrier will be liable, for any damage which may be accused thereby to any person who is lawfully in possession of the part of the air waybill. Under the Montreal Convention, the carrier is liable by application of principle of strict liability for the damage sustained during the carriage of cargo by air. The carrier is liable for the destruction or loss of, or damage to cargo and delay during the carriage by air. The period of the carriage by air does not extend to any carriage by land, by sea or by inland waterway performed outside an airport. Under the Montreal Convention, the carrier's liability is limited to a sum of 17 Special Drawing Rights per kilogramme. Any provision tending to relieve the carrier of liability or to fix a lower limit than that which is laid down in this Convention shall be and void. Under the Montreal Convention, if the carrier proves that the damage was caused by the negligence or other wrongful act or omission of the person claiming compensation, or the person from whom he derives his rights, the carrier shall be wholly or partly exonerated from ist liability to the claimant to the extent that such negligence or wrongful act or omission caused the damage. Under the Montreal Convention, any action for damages, however founded, whether under this Convention or in contract or in tort or otherwise, can only be brought subject to the conditions and such limits of liability as are set out in this Convention. Under the Montreal Convention, in the case of damage the person entitled to delivery must complain to the carrier forthwith after the discovery of the damage, and at the latest, within fourteen days from the date of receipt of cargo. In the case of delay, the complaint must be made at the latest within twenty-one days from the date on which the cargo has been placed at his disposal. if no complaint is made within the times aforesaid, no action shall lie against the carrier, save in the case of fraud on its part. Under the Montreal Convention, the right to damage shall be extinguished if an action is not brought within a period of two years, reckoned from the date of arrival at the destination, or from the date on which the aircraft ought to have arrived, or from the date on which the carriage stopped. In conclusion, the Montreal Convention has main outstanding issues with respect to the carrier's liability in respect of the carriage of cargo by air as follows : The amounts of limits of the carrier's liability, the duration of the carrier's liability, and the aviation liability insurance. Therefore, the conditions and limits of the carrier's liability under the Montreal Convention should be readjusted and regulated in detail.

• Journal of Korean Academy of Nursing
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• v.4 no.1
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• pp.162-178
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• 1974

The present study is purported to provide a basic information to be utilized by nurses to care and attend effectively for patients nearing the moment of death. Therefore, the primary purpose of the study has been placed upon grasping an understanding of the trends of death in general. For this purpose: 1. By utilizing the schneidman questionnaire, the trend of death has been categorized by 6 parts and analyzed. 2. A search has been conducted to find out dying patient's needs, nurse's attitudes viewed by the patient, and nurse attitudes to dying patient. The followings are itemized results of analysis: 1. Analysis by the schneidman questionnaire. (1) In general concepts of death. the first sighting of the occurrence of death was experienced upon strangers, grandfather and great grandfather. The death is openly discussed among people of all ages and sex. Ages in which the death is mostly feared were from 12 to well over 70 yews old that are evenly distributed regardless of difference in age. (2) As to the attitudes toward death the occurrence of death to most closely associated person influenced most upon the attitude of their own termination of lives. Among the reading materials, the maximum influence was effected by the Bible. In terms of religion, the thoughts of death were Influenced by religions education in case of the believers of the western religions (36%), and by their own health and physical conditions in case of the believers in the oriental religions (35%). In case of non-believer, their attitude toward death were largely determined through their own thinking meditation (45%). People aged 20 or thereunder revealed that they wished to know the day of their own death to be occurred (58%). However, the older the less thor wanted to know. (3) As to the choosing the time of death, 57% preferred senility, and 30% preferred the time in mediately following the prime period of their lives in general. In terms of religion, 85% of the believer in the oriental religion preferred senility, and 67% in the western religion, 58% in others, Therefore. the desiring of their lives to be terminated in earlier stage, not by the natural senility. sequenced as follows : Others, western religions and oriental religions. (4) Referring to the disposal of the corpse under the assumption that it had already occurred, majority desired the burial system. There has been seen a slight tendency to consider the importance of holding funeral services for the sake of survivors. Concerning the life insurance policy, it showed that the nurse had less belief in it than the patient (5) Upon the subject of life-after-death. religion wise, 72% of western religion believers preferred to have an existence of life-after-death: Among the believers of oriental regions, 35% desired this category, 30% did not mind either way. and 35% did not desire the existence of such a life-after-death. In others, 53% did not mind whether or not such a life existed. (6) In general, serious thoughts were not being attended to the commitment of suicide. 37% emphasized that such an act should be prevented. However, 30% insisted that such commitment should not be bothered, and that society possesses no right to prevented it. More male wished to commit suicide (13%) than females (9%). 2. Nurse's attitudes toward terminal patients and patient's needs. In the instance where the patient realized that their death is imminent, most of them showed desire to discuses mainly on the problems of life. When faced a situation of this nature, it is revealed that 40% of nurses could not furnish appropriate care for them.

• Korean Journal of Poultry Science
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• v.15 no.2
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• pp.81-91
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• 1988

The purpose of this research is to analyze the tendencies of poultry consumption in Korea. The information used is the data collected three times during the period from Sept. 1, 1985 to April 30, 1987 throughout the major cities. Those who participated in the survey are 2, 598 including housewives, nutritionists, cookers, group feeding institutions, woman's organizations, and the students of doing nutrition－related studies. Consumer preferences for poultry meat and eggs tend to move toward high quality and more strict sanitary standards. Following this line of consumer preference changes, the poultry product marketing supported by cold chain system is rapidly developing. Household consumption of poultry meat largely consists of hi－and semi－broilers but the household demand for these two broilers tends to decrease steadily over time. In general poultry meat consumption appears to be affected by consumer taste rather than market factors such as prices. In addition consumer choices are quite different depending on poultry meat parts which are preferred in order of drum sticks, wings, and breasts. In particular drum sticks are most preferred than any other parts. An important problem in poultry production is related to consumption seasonality since large part of poultry meat consumption is concentrated during the summer season. Another problem is associated with little development of cooking methods. At present there are two types of primary commercial cooking techniques, fries and samgaetang (boiled chicken with jinsang and rice). For promoting domestic poultry meat disposal and reducing the demand seasonality, new cooking methods should be developed and followed by more aggresive advertisements. In domestic egg trade, smaller packing units(i.e., 10 eggs per unit) tend to bi preferred to large ones (i.e., 30 eggs per unit). In consumers egg purchasing decisions nearness to the shops and convenience appear to be important factors. For egg shell colors consumers recognize that there is no difference in nutritional values. However, survey results show that consumers highest preference lies in eggs with brown color. Eggs are most popular among children and preferred in order of middle－and high－school students, 17-25 age people, and adults. Egg prices are concieved relatively cheap to its nutritional values. In house－holds eggs are consumed in the forms of fries, side dishes, and lunch basket dishes. However, high level of cholesterol content in eggs appears to be an important problem in promoting eggs consumption.